Coal Combustion Residue Impoundment Round 9 - Dam Assessment Report

DRAFT

Flint Creek Power Plant Bottom Ash Dike SWEPCO Gentry, Arkansas

Prepared for:

United States Environmental Protection Agency Office of Resource Conservation and Recovery

Prepared by:

Dewberry & Davis, LLC Fairfax, Virginia

Under Contract Number: EP-09W001727 April 2011

DRAFT INTRODUCTION, SUMMARY CONCLUSIONS AND RECOMMENDATIONS

The release of over five million cubic yards of coal combustion waste from the Tennessee Valley Authority’s Kingston, Tennessee facility in December 2008 flooded more than 300 acres of land, damaging homes and property. In response, the U.S. EPA is assessing the stability and functionality of the coal combustion ash impoundments and other management units across the country and, as necessary, identifying any needed corrective measures.

This assessment of the stability and functionality of the Flint Creek Power Plant primary and secondary bottom ash ponds are based on a review of available documents and on the site assessment conducted by Dewberry personnel on February 15, 2011, we found the supporting technical documentation adequate (Section 1.1.3).

In summary, the Flint Creek Power Plant primary and secondary bottom ash ponds are SATISFACTORY for continued safe and reliable operation, with no recognized existing or potential management unit safety deficiencies.

PURPOSE AND SCOPE

The U.S. Environmental Protection Agency (EPA) is embarking on an initiative to investigate the potential for catastrophic failure of Coal Combustion Surface Impoundments (i.e., management unit) from occurring at electric utilities in an effort to protect lives and property from the consequences of a dam failure or the improper release of impounded slurry. The EPA initiative is intended to identify conditions that may adversely affect the structural stability and functionality of a management unit and its appurtenant structures (if present); to note the extent of deterioration (if present), status of maintenance and/or a need for immediate repair; to evaluate conformity with current design and construction practices; and to determine the hazard potential classification for units not currently classified by the management unit owner or by a state or federal agency. The initiative will address management units that are classified as having a Less-than-Low, Low, Significant or High Hazard Potential ranking. (For Classification, see pp. 3-8 of the 2004 Federal Guidelines for Dam Safety.)

In early 2009, the EPA sent its first wave of letters to coal-fired electric utilities seeking information on the safety of surface impoundments and similar facilities that receive liquid-borne material that store or dispose of coal combustion residue. This letter was issued under the authority of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Section 104(e), to assist the Agency in assessing the structural stability and functionality of such management units, including which facilities should be visited to perform a safety assessment of the berms, dikes, and dams used in the construction of these impoundments.

Flint Creek Power Plant ii SWEPCO Coal Combustion Residue Impoundment Gentry, AK Dam Assessment Report DRAFT EPA requested that utility companies identify all management units including surface impoundments or similar diked or bermed management units or management units designated as landfills that receive liquid-borne material used for the storage or disposal of residuals or by- products from the combustion of coal, including, but not limited to, fly ash, bottom ash, boiler slag, or flue gas emission control residuals. Utility companies provided information on the size, design, age and the amount of material placed in the units. The EPA used the information received from the utilities to determine preliminarily which management units had or potentially could have High Hazard Potential ranking.

The purpose of this report is to evaluate the condition and potential of residue release from coal combustion residue management units. This evaluation included a site visit. Prior to conducting the site visit, a two-person team reviewed the information submitted to EPA, reviewed any relevant publicly available information from state or federal agencies regarding the unit hazard potential classification (if any) and accepted information provided via telephone communication with the management unit owner. Also, after the field visit, additional information was received by Dewberry & Davis LLC about the Flint Creek Power Plant primary and secondary bottom ash pond that was reviewed and used in preparation of this report.

Factors considered in determining the hazard potential classification of the management unit(s) included the age and size of the impoundment, the quantity of coal combustion residuals or by- products that were stored or disposed of in these impoundments, its past operating history, and its geographic location relative to down gradient population centers and/or sensitive environmental systems.

This report presents the opinion of the assessment team as to the potential of catastrophic failure and reports on the condition of the management unit(s).

LIMITATIONS The assessment of dam safety reported herein is based on field observations and review of readily available information provided by the owner/operator of the subject coal combustion residue management unit(s). Qualified Dewberry engineering personnel performed the field observations and review and made the assessment in conformance with the required scope of work and in accordance with reasonable and acceptable engineering practices. No other warranty, either written or implied, is made with regard to our assessment of dam safety.

Flint Creek Power Plant iii SWEPCO Coal Combustion Residue Impoundment Gentry, AK Dam Assessment Report DRAFT Table of Contents Page

INTRODUCTION, SUMMARY CONCLUSIONS AND RECOMMENDATIONS ...... II PURPOSE AND SCOPE ...... II 1.0 CONCLUSIONS AND RECOMMENDATIONS ...... 1-1

1.1 CONCLUSIONS ...... 1-1 1.1.1 Conclusions Regarding the Structural Soundness of the Management Unit(s) ...... 1-1 1.1.2 Conclusions Regarding the Hydrologic/Hydraulic Safety of the Management Unit(s) ...... 1-1 1.1.3 Conclusions Regarding the Adequacy of Supporting Technical Documentation ...... 1-1 1.1.4 Conclusions Regarding the Description of the Management Unit(s) ...... 1-1 1.1.5 Conclusions Regarding the Field Observations ...... 1-1 1.1.6 Conclusions Regarding the Adequacy of Maintenance and Methods of Operation ...... 1-2 1.1.7 Conclusions Regarding the Adequacy of the Surveillance and Monitoring Program ...... 1-2 1.1.8 Classification Regarding Suitability for Continued Safe and Reliable Operation ...... 1-2 1.2 RECOMMENDATIONS ...... 1-2 1.3 PARTICIPANTS AND ACKNOWLEDGEMENT ...... 1-2 1.3.1 List of Participants ...... 1-2 1.3.2 Acknowledgement and Signature ...... 1-3 2.0 DESCRIPTION OF THE COAL COMBUSTION RESIDUE MANAGEMENT UNIT(S) ...... 2-1

2.1 LOCATION AND GENERAL DESCRIPTION ...... 2-1 2.2 COAL COMBUSTION RESIDUE HANDLING ...... 2-2 2.2.1 Fly Ash ...... 2-2 2.2.2 Bottom Ash ...... 2-2 2.2.3 Boiler Slag ...... 2-2 2.2.4 Flue Gas Desulfurization Sludge ...... 2-2 2.3 SIZE AND HAZARD CLASSIFICATION ...... 2-2 2.4 AMOUNT AND TYPE OF RESIDUALS CURRENTLY CONTAINED IN THE UNIT(S) AND MAXIMUM CAPACITY 2-3 2.5 PRINCIPAL PROJECT STRUCTURES ...... 2-4 2.5.1 Earth Embankment ...... 2-4 2.5.2 Outlet Structures ...... 2-4 3.0 SUMMARY OF RELEVANT REPORTS, PERMITS, AND INCIDENTS ...... 3-1

3.1 SUMMARY OF LOCAL, STATE, AND FEDERAL ENVIRONMENTAL PERMITS ...... 3-1 3.2 SUMMARY OF SPILL/RELEASE INCIDENTS ...... 3-1 4.0 SUMMARY OF HISTORY OF CONSTRUCTION AND OPERATION ...... 4-1

4.1 SUMMARY OF CONSTRUCTION HISTORY ...... 4-1 4.1.1 Original Construction ...... 4-1 4.1.2 Significant Changes/Modifications in Design since Original Construction ...... 4-1 4.1.3 Significant Repairs/Rehabilitation since Original Construction ...... 4-1 4.2 SUMMARY OF OPERATIONAL PROCEDURES ...... 4-1 4.2.1 Original Operational Procedures ...... 4-1 4.2.2 Significant Changes in Operational Procedures and Original Startup ...... 4-1 4.2.3 Current Operational Procedures ...... 4-1 4.2.4 Other Notable Events since Original Startup ...... 4-1 Flint Creek Power Plant iv SWEPCO Coal Combustion Residue Impoundment Gentry, AK Dam Assessment Report DRAFT 5.0 FIELD OBSERVATIONS ...... 5-1

5.1 PROJECT OVERVIEW AND SIGNIFICANT FINDINGS ...... 5-1 5.2 PRIMARY/SECONDARY POND WEST DIKE ...... 5-1 5.2.1 Crest...... 5-1 5.2.2 Upstream/Inside Slope ...... 5-2 5.2.3 Downstream/Outside Slope and Toe ...... 5-2 5.2.4 Abutments and Groin Areas ...... 5-3 5.3 INCISED PRIMARY AND SECONDARY PONDS ...... 5-3 5.3.1 Incised ...... 5-3 5.4 OUTLET STRUCTURES ...... 5-4 5.4.1 Overflow Structure ...... 5-4 5.4.2 Outlet Conduit ...... 5-4 5.4.3 Emergency Spillway ...... 5-5 5.4.4 Low Level Outlet ...... 5-5 6.0 HYDROLOGIC/HYDRAULIC SAFETY ...... 6-1

6.1 SUPPORTING TECHNICAL DOCUMENTATION ...... 6-1 6.1.1 Flood of Record and Inflow Design Flood ...... 6-1 6.1.2 Spillway Rating ...... 6-1 6.1.3 Downstream Flood Analysis ...... 6-1 6.2 ADEQUACY OF SUPPORTING TECHNICAL DOCUMENTATION ...... 6-1 6.3 ASSESSMENT OF HYDROLOGIC/HYDRAULIC SAFETY ...... 6-1 7.0 STRUCTURAL STABILITY ...... 7-1

7.1 SUPPORTING TECHNICAL DOCUMENTATION ...... 7-1 7.1.1 Stability Analyses and Load Cases Analyzed ...... 7-1 7.1.2 Design Parameters and Dam Materials ...... 7-1 7.1.3 Uplift and/or Phreatic Surface Assumptions ...... 7-1 7.1.4 Factors of Safety and Base Stresses ...... 7-1 The August 2010 analysis calculated Factors of Safety for the west dike of both bottom ash ponds for the three conditions. All calculated Factors of Safety met or exceeded the minimum required by the U.S. Army Corps of Engineers...... 7-1 7.1.5 Liquefaction Potential...... 7-2 7.1.6 Critical Geological Conditions ...... 7-2 7.2 ADEQUACY OF SUPPORTING TECHNICAL DOCUMENTATION ...... 7-2 7.3 ASSESSMENT OF STRUCTURAL STABILITY ...... 7-2 8.0 ADEQUACY OF MAINTENANCE AND METHODS OF OPERATION ...... 8-1

8.1 OPERATING PROCEDURES ...... 8-1 8.2 MAINTENANCE OF THE DAM AND PROJECT FACILITIES ...... 8-1 8.3 ASSESSMENT OF MAINTENANCE AND METHODS OF OPERATIONS ...... 8-1 8.3.1 Adequacy of Operating Procedures ...... 8-1 8.3.2 Adequacy of Maintenance ...... 8-1

Flint Creek Power Plant v SWEPCO Coal Combustion Residue Impoundment Gentry, AK Dam Assessment Report DRAFT 9.0 ADEQUACY OF SURVEILLANCE AND MONITORING PROGRAM ...... 9-1

9.1 SURVEILLANCE PROCEDURES ...... 9-1 9.2 INSTRUMENTATION MONITORING ...... 9-1 9.3 ASSESSMENT OF SURVEILLANCE AND MONITORING PROGRAM ...... 9-1 9.3.1 Adequacy of Inspection Program ...... 9-1 9.3.2 Adequacy of Instrumentation Monitoring Program ...... 9-1

Flint Creek Power Plant vi SWEPCO Coal Combustion Residue Impoundment Gentry, AK Dam Assessment Report DRAFT APPENDIX A

Doc 01: Project Location Map Doc 02: Aerial Photography Doc 03: Steam Electric Questions and Responses Doc 04: Ash Berm and Connecting Canal Plan FCX3-1, dated 8/14/75 Doc 05: Report for the Inspection of Flint Creek Ash Pond, May 2009 Doc 06: Dam & Dike Inspection Report, September 16 2009 Doc 07: NPDES Permit Doc 08: Ash Pond Dike Cross Sections FCX3-2, dated 7/10/74 Doc 09: Secondary Ash Settling Pond Weir FCX104-1, dated 9/22/09 Doc 10: Ash Storage Basin Control Structure FCX29-2, dated 4/7/76 Doc 11: Hydraulic Analysis of Flint Creek PP Ash Ponds, January 2011 Doc 12: Design Calculations Secondary Ash Settling Pond Weir, 9/21/09 Doc 13,13a: Embankment Investigation, dated August 2010 Doc 14: Site Work Contract, dated 9/4/74 Doc 15: Quarterly Dam inspections

APPENDIX B

Doc 16: Dam Inspection Check List Form Primary Bottom Ash Pond Doc 17: Dam Inspection Check List Form Secondary Bottom Ash Pond

Flint Creek Power Plant vii SWEPCO Coal Combustion Residue Impoundment Gentry, AK Dam Assessment Report DRAFT 1.0 CONCLUSIONS AND RECOMMENDATIONS

1.1 CONCLUSIONS

Conclusions are based on visual observations from a one-day site visit on February 15, 2011, and review of technical documentation provided by SWEPCO.

1.1.1 Conclusions Regarding the Structural Soundness of the Management Unit(s)

The dike embankments and spillway appear to be structurally sound based on a review of the engineering data provided by the owner’s technical staff and Dewberry engineers’ observations during the site visit.

1.1.2 Conclusions Regarding the Hydrologic/Hydraulic Safety of the Management Unit(s)

Hydrologic and hydraulic analyses provided to Dewberry indicate adequate impoundment capacity to contain the 1-percent probability/Probable Maximum Precipitation design storm without overtopping the dikes.

1.1.3 Conclusions Regarding the Adequacy of Supporting Technical Documentation

The supporting technical documentation is adequate. Engineering documentation reviewed is referenced in Appendix A.

1.1.4 Conclusions Regarding the Description of the Management Unit(s)

The description of the management unit provided by the owner was an accurate representation of what Dewberry observed in the field.

1.1.5 Conclusions Regarding the Field Observations

Dewberry staff was provided access to all areas in the vicinity of the management unit required to conduct a thorough field observation. The visible parts of the embankment dikes and outlet structure were observed to have no signs of overstress, significant settlement, shear failure, or other signs of instability. Embankments appear structurally sound. There are no apparent indications of unsafe conditions or conditions needing remedial action.

Flint Creek Power Plant 1-1 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 1.1.6 Conclusions Regarding the Adequacy of Maintenance and Methods of Operation

The current maintenance and methods of operation appear to be adequate for the bottom ash management unit. There was no evidence of significant embankment repairs or prior releases observed during the field inspection.

1.1.7 Conclusions Regarding the Adequacy of the Surveillance and Monitoring Program

The surveillance program appears to be adequate. The original management unit dikes were not instrumented; four piezometers were installed in 2010 for monitor ground water levels. Based on the size of the dikes, the portion of the impoundment currently used to store bottom ash and storm water, the history of satisfactory performance and the current inspection program, no additional dike monitoring system is needed at this time.

1.1.8 Classification Regarding Suitability for Continued Safe and Reliable Operation

The facility is SATISFACTORY for continued safe and reliable operation. No existing or potential management unit safety deficiencies are recognized. Acceptable performance is expected under all applicable loading conditions (static, hydrologic, seismic) in accordance with the applicable criteria.

1.2 RECOMMENDATIONS

No recommendations appear warranted at this time.

1.3 PARTICIPANTS AND ACKNOWLEDGEMENT

1.3.1 List of Participants

W. Greg Carter P.E., American Electric Power (AEP) Ivaunna Neigler, American Electric Power (AEP) Carl Handley, American Electric Power (AEP) Scott Carney, American Electric Power (AEP) William R Smith P.E., American Electric Power (AEP) Michael McLaren P.E., Dewberry Kyle Shepard P.E., Dewberry

Flint Creek Power Plant 1-2 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 1.3.2 Acknowledgement and Signature

I acknowledge that the management unit referenced herein has been assessed on February 15, 2011.

Michael J McLaren, P.E.

Arkansas License #13067

Flint Creek Power Plant 1-3 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 2.0 DESCRIPTION OF THE COAL COMBUSTION RESIDUE MANAGEMENT UNIT(S)

2.1 LOCATION AND GENERAL DESCRIPTION

The Flint Creek Power Plant is located next to Flint Creek near Gentry, Arkansas. The plant is operated by SWEPCO. The primary and secondary bottom ash ponds are adjacent to the plant and the plant cooling pond. A project location map is provided in Appendix A – Doc 1. An Aerial photograph of the impoundment is provided in Appendix A – Doc 2.

The Flint Creek Power Plant bottom ash ponds are cross valley embankments constructed of native clayey fill that impounds bottom ash and ash pond water. Construction started in 1974 and was completed in 1978.

The maximum height of the primary dike is 46.5 feet while the secondary dike maximum height is 35 feet. The primary impoundment area (referred to herein as the Primary Bottom Ash Pond) is approximately 42.8 acres and has a storage capacity of 484.1 acre-ft (See Appendix A – Doc 3). The secondary impoundment area (referred to herein as the Secondary Bottom Ash Pond) is approximately 3.7 acres and has a storage capacity of 24.3 acre-ft (See Appendix A – Doc 3). Construction began on the dike in 1974, and the plant opened for operation in 1978.

Table 2.1: Summary of Dam Dimensions and Size Primary Bottom Ash Pond Dam Height (ft) 46.5 Crest Width (ft) 12 Length (ft) 820 Side Slopes (upstream) H:V 3:1 Side Slopes (downstream) H:V 3:1 Table 2.1a: Summary of Dam Dimensions and Size Secondary Bottom Ash Pond Dam Height (ft) 35.0 Crest Width (ft) 12 Length (ft) 750 Side Slopes (upstream) H:V 3:1 Side Slopes (downstream) H:V 3:1

Flint Creek Power Plant 2-1 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 2.2 COAL COMBUSTION RESIDUE HANDLING

2.2.1 Fly Ash

Fly ash is removed from flue gas by electrostatic precipitators (ESPs). Fly ash is pneumatically transported from ESPs by a hydrovactor system into the fly ash silo. Some ash becomes entrained in the hydrovactor water stream and is discharged to the primary ash pond. Ash stored in the fly ash silo is disposed in the on-site landfill, or marketed.

2.2.2 Bottom Ash

Bottom ash accumulates at the bottom of the boiler before it is sluiced into the primary ash pond, approximately twice daily. As necessary, bottom ash is stockpiled in the primary ash pond, or dredged for on-site landfill disposal or use.

2.2.3 Boiler Slag

Boiler slag is managed with bottom ash during normal boiler operations. Approximately twice per year, the boiler is shut down for cleaning and residual slag is removed and disposed in the on-site landfill.

2.2.4 Flue Gas Desulfurization Sludge

The Flint Creek Power Plant does not operate a flue gas desulfurization system.

2.3 SIZE AND HAZARD CLASSIFICATION

The classification for the Primary Bottom Ash Pond, based on the height of the dam, is “intermediate” and, based on the storage capacity, is “small.” The classification for the Secondary Bottom Ash Pond, based on the height of the dam, is “small” and, based on the storage capacity, is “small” in accordance with USACE Recommended Guidelines for Safety Inspections of Dams ER 1110-2-106 criteria summarized in Table 2.3a.

Flint Creek Power Plant 2-2 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT Table 2.3a: USACE ER 1110-2-106 Size Classification Impoundment Category Storage (Ac-ft) Height (ft) Small 50 and < 1,000 25 and < 40 Intermediate 1,000 and < 50,000 40 and < 100 Large > 50,000 > 100

The bottom ash ponds are not in the National Inventory of Dams; therefore these dikes do not have established hazard classifications. Dewberry conducted a qualitative hazard classification based on the 2004 Federal Guidelines for Dam Safety classification system (shown in Table 2.3b).

Table 2.3b: FEMA Federal Guidelines for Dam Safety Hazard Classification Loss of Human Life Economic, Environmental, Lifeline Losses Low None Expected Low and generally limited to owner Significant None Expected Yes High Probable. One or more Yes (but not necessary for expected classification)

Loss of human life is not probable in the event of a catastrophic failure of the dikes and a failure of the dikes is expected to have a low economic and environmental impact. Therefore, Dewberry evaluated the bottom ash ponds as “Low hazard potential.”

2.4 AMOUNT AND TYPE OF RESIDUALS CURRENTLY CONTAINED IN THE UNIT(S) AND MAXIMUM CAPACITY

The data reviewed by Dewberry did not include the volume of the residuals stored in the Primary or Secondary Bottom Ash Pond at the time of inspection. Volume information provided in Tables 2.3a and 2.3b was measured on 12/31/2008.

Table 2.3a: Maximum Capacity of Unit Primary Bottom Ash Pond Surface Area (acre)1 42.8 Current Storage Capacity (cubic yards)1 80,700 Total Storage Capacity (acre-feet) 484.1 Crest Elevation (feet) 46.5 Normal Pond Level (feet) 36.5

Flint Creek Power Plant 2-3 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT Table 2.3b: Maximum Capacity of Unit Secondary Bottom Ash Pond Surface Area (acre)1 3.7 Current Storage Capacity (cubic yards)1 Minimal- Ash is routinely removed for beneficial use Total Storage Capacity (acre-feet) 24.3 Crest Elevation (feet) 35 Normal Pond Level (feet) 22

2.5 PRINCIPAL PROJECT STRUCTURES

2.5.1 Earth Embankment

The bottom ash pond is divided into two impoundments in series. The primary dam is an 820-foot long cross-valley dam. The secondary dam is a 750-foot long cross-valley dam. The dikes are earthen embankments with a crest width of 12 feet. The inside and exterior slopes are approximately 3H:1V (See Appendix A – Doc 4). The lower portions of the slopes are protected with rip rap and the upper portions are grass covered.

2.5.2 Outlet Structures

The principal spillway at the Primary Bottom Ash Pond is a concrete curb and a small weir box at a slightly lower elevation. The principal spillway at the Secondary Bottom Ash Pond is a concrete structure with a series of horizontal orifices and a weir that discharges to a new concrete spillway with a weir box that discharges into the cooling lake. The emergency spillway is a concrete curb that is approximately 2.5 feet above the weir invert and discharges to the cooling lake.

2.6 CRITICAL INFRASTRUCTURE WITHIN FIVE MILES DOWN GRADIENT

Critical infrastructure inventory data was not provided to Dewberry for review.

Based on the available area topographic maps, surface drainage in the area of the bottom ash ponds are to the southwest through the cooling lake. Releases from the impoundments would not impact the water level in the cooling lake significantly.

The nearest town, Watts Oklahoma, is approximately 32 miles downstream of the impoundment.

Flint Creek Power Plant 2-4 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 3.0 SUMMARY OF RELEVANT REPORTS, PERMITS, AND INCIDENTS

Summary of Reports on the Safety of the Management Unit

SWEPCO provided two dam inspection reports:

• Report For The Inspection Of Flint Creek Ash Pond, Golder Associates May 2009 (See Appendix A – Doc 5)

• Dam & Dike Inspection Report, SWEPCO, September 16, 2009 (See Appendix A – Doc 6)

The reports concluded that the structures appeared to be performing adequately with only minor maintenance items that need to be addressed. No conditions were observed that would affect the continued safe operation of the impoundment.

3.1 SUMMARY OF LOCAL, STATE, AND FEDERAL ENVIRONMENTAL PERMITS

The dams for the Primary and Secondary Bottom Ash Ponds are not permitted.

Discharge from the impoundment is regulated by the Arkansas Department of Environmental Quality and the impoundment has been issued a National Pollutant Discharge Elimination System Permit. Permit No. AR0037842 was issued March 1, 2006 (See Appendix A – Doc 7).

3.2 SUMMARY OF SPILL/RELEASE INCIDENTS

Data reviewed by Dewberry did not indicate any spills, unpermitted releases, or other performance related problems with the dam over the last 10 years.

Flint Creek Power Plant 3-1 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 4.0 SUMMARY OF HISTORY OF CONSTRUCTION AND OPERATION

4.1 SUMMARY OF CONSTRUCTION HISTORY

4.1.1 Original Construction

The Flint Creek Power Plant Bottom Ash Ponds were constructed beginning in 1974, and were completed in 1978. The original design crest was 1,155 feet (See Appendix A – Doc 8).

4.1.2 Significant Changes/Modifications in Design since Original Construction

The principal spillway for the Secondary Bottom Ash Pond was reconstructed in 2009 with a new weir box and 13-foot wide weir with a crest elevation of 1,142.5 feet. Also the emergency concrete curb spillway was raised to 1,145 feet (See Appendix A – Doc 9).

4.1.3 Significant Repairs/Rehabilitation since Original Construction

No documentation was provided to indicate any significant repair/rehabilitation has taken place since the original construction.

4.2 SUMMARY OF OPERATIONAL PROCEDURES

4.2.1 Original Operational Procedures

The impoundment was designed and operated for bottom ash sedimentation and control. The pond receives plant process waste water, and coal combustion waste slurry. Treated (via sedimentation) process water is discharged through an overflow outlet structure.

4.2.2 Significant Changes in Operational Procedures and Original Startup

No documents were provided to indicate any operational procedures have changed.

4.2.3 Current Operational Procedures

No documents were provided to indicate any operational procedures have changed.

4.2.4 Other Notable Events since Original Startup

No additional information was provided to Dewberry addressing other notable events impacting the operation of the impoundments.

Flint Creek Power Plant 4-1 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 5.0 FIELD OBSERVATIONS

5.1 PROJECT OVERVIEW AND SIGNIFICANT FINDINGS

Dewberry personnel Michael McLaren, P.E. and Kyle Shepard, P.E. performed a site visit on February15, 2011 with the participants listed in Section 1.3.

The site visit began at 9:00 AM. The weather was cool and overcast. Photographs were taken of conditions observed. Additional site information is provided in the Dam Inspection Checklists in Appendix B. Selected photographs are included here for ease of visual reference. All pictures were taken by Dewberry personnel during the site visit.

The overall assessment of the dam was that it was in satisfactory condition and no significant findings were noted.

5.2 PRIMARY/SECONDARY POND WEST DIKE

5.2.1 Crest

The west dike is shared by both the primary and secondary pond. The crest had no signs of depressions, tension cracks, or other indications of settlement or shear failure, and appeared to be in satisfactory condition. Figure 5.2.1-1 shows conditions of the crest on the west dike.

Figure 5.2.1-1: Photo Showing Crest, West Dike

Flint Creek Power Plant 5-1 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 5.2.2 Upstream/Inside Slope

There were no observed scarps, sloughs, bulging, cracks, or depressions or other indications of slope instability or signs of erosion. The lower portion of the inside slope was protected with rip rap. Figure 5.2.2-1 shows the general condition of the inside slope, west dike.

Figure 5.2.2-1: General condition of the inside slope, west dike

5.2.3 Downstream/Outside Slope and Toe

There were no observed scarps, sloughs, bulging, cracks, or depressions or other indications of slope instability or signs of erosion. The lower portion of the outside slope was protected with rip rap. Figure 5.2.3-1 shows the general condition of the outside slope of the Primary Bottom Ash Pond; the cooling pond is on the left side of the picture.

Flint Creek Power Plant 5-2 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT

Figure 5.2.3-1: General condition of the west dike outside slope and groin

5.2.4 Abutments and Groin Areas

There were no observed scarps, sloughs, bulging, cracks, or depressions or other indications of slope instability or signs of erosion. Figure 5.2.3-1 also shows the general condition of the groin.

5.3 INCISED PRIMARY AND SECONDARY PONDS

5.3.1 Incised

For both the primary and secondary bottom ash ponds, the north, south, and east sides are incised so no visual inspection was required.

Figure 5.3.1-1: Incised pond

Flint Creek Power Plant 5-3 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 5.4 OUTLET STRUCTURES

5.4.1 Overflow Structure

As described on the drawings (see Appendix A – Doc 9, 10), the principal spillway at the secondary bottom ash pond is a concrete structure with a series of horizontal orifices. The plant has added a new weir box with a 13-foot wide weir with a crest elevation of 1,142.5 feet which discharges into the cooling lake.

The primary overflow structure was observed to be working properly, discharging flow from the bottom ash ponds. The outlet structure visually appeared to be in satisfactory condition. There were no signs of clogging of the spillway and the water exiting the outlet was flowing clear. Figure 5.4.1-1 shows the main outlet structure.

Figure 5.4.1-1. Main outlet structure

5.4.2 Outlet Conduit

The outlet weir appeared to be in good shape and operating normally with no sign of clogging and the water exiting the outlet was flowing clear. Figure 5.4.2-1 shows the water discharging from the main spillway outfall.

Flint Creek Power Plant 5-4 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT

Figure 5.4.2-1. Water discharging from the main spillway outfall

5.4.3 Emergency Spillway

The Emergency Spillway is a concrete curb that was recently extended up to an elevation of 1,145 feet. If overtopped, water would drain to the cooling lake via overland flow.

5.4.4 Low Level Outlet

No low level outlet is present.

Flint Creek Power Plant 5-5 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 6.0 HYDROLOGIC/HYDRAULIC SAFETY

6.1 SUPPORTING TECHNICAL DOCUMENTATION

6.1.1 Flood of Record and Inflow Design Flood

SWEPCO provided a hydraulic analysis report titled, “Hydraulic Analysis of Flint Creek Power Plant Ash Ponds, Freese and Nichols, Inc. January 2011” (See Appendix A – DOC 11). The report provided information on the flood of record and inflow design criteria.

6.1.2 Spillway Rating

SWEPCO provided a spillway analysis in the “Design Calculations Secondary Ash Settling Pond Weir, American Electric Power Flint Creek Power Plant, September 21, 2009” (See Appendix A – DOC 12).

6.1.3 Downstream Flood Analysis

No downstream flood analysis (breach analysis) was provided for review.

6.2 ADEQUACY OF SUPPORTING TECHNICAL DOCUMENTATION

Supporting documentation reviewed by Dewberry was adequate.

6.3 ASSESSMENT OF HYDROLOGIC/HYDRAULIC SAFETY

Based on the calculations provided in the hydrologic and hydraulic study (See Appendix A – Doc 11) the bottom ash ponds can retain the 1-percent design storm event. Hence dike failure by overtopping seems improbable.

Flint Creek Power Plant 6-1 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 7.0 STRUCTURAL STABILITY

7.1 SUPPORTING TECHNICAL DOCUMENTATION

7.1.1 Stability Analyses and Load Cases Analyzed

ETTL Engineers & Consultants performed an embankment investigation in August 2010. (See Appendix A – Doc 13.)

The Stability analysis used the computer program Geostase. The program is capable of calculating the factor of safety for potential failure surfaces using different methods; the modified Bishop method was used. Conditions assessed were:

• Steady state conditions based on ground water levels measured at the time of the borings

• Seismic loading applied to steady state loading

• Static analysis under rapid drawdown conditions

7.1.2 Design Parameters and Dam Materials

Design documentation provided to Dewberry for review was the September 4, 1974 original contract, SWEPCO/ Machen Construction Company Flint Creek Power Plant Site work. (See Appendix A – Doc 14.)

7.1.3 Uplift and/or Phreatic Surface Assumptions

The ETTL Engineers & Consultants report referenced above included an embankment investigation and analysis of phreatic elevations. (See Appendix A – Doc 13.)

7.1.4 Factors of Safety and Base Stresses

The August 2010 analysis calculated Factors of Safety for the west dike of both bottom ash ponds for the three conditions. All calculated Factors of Safety met or exceeded the minimum required by the U.S. Army Corps of Engineers.

Flint Creek Power Plant 7-1 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT Table 7.1.4 Factors of Safety for Flint Creek Power Plant

Required Safety West Dike Factor (US Computed Loading Army Corps of Average Safety Condition Soil Strength Engineers) Factor Steady State Full Design 1.9 (Primary) 1.5 Strength 1.6 (Secondary) Steady State Parameters 1.3 (Primary) with Seismic 1.2 1.2 (Secondary) Loading Rapid 1.2 (Primary) Drawdown 1.5 (Secondary) Conditions

7.1.5 Liquefaction Potential

ETTL Engineers & Consultants performed an embankment investigation in August of 2010. (See Appendix A – Doc 13). The report indicates that the foundation soil conditions do not appear to be susceptible to liquefaction.

7.1.6 Critical Geological Conditions

There was no documentation provided to Dewberry that included an evaluation of Critical Geological Conditions.

7.2 ADEQUACY OF SUPPORTING TECHNICAL DOCUMENTATION

Structural stability documentation is adequate.

7.3 ASSESSMENT OF STRUCTURAL STABILITY

Overall, the structural stability of the dam appears to be satisfactory based on the following observations:

• The crest appeared free of depressions and no significant vertical or horizontal alignment variations were observed.

• There was no indication of major scarps, sloughs or bulging along the dikes.

• Boils, sinks or uncontrolled seepage was not observed along slopes, groins or toes of the dike.

• The computed factors of safety comply with accepted criteria.

Flint Creek Power Plant 7-2 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 8.0 ADEQUACY OF MAINTENANCE AND METHODS OF OPERATION

8.1 OPERATING PROCEDURES

The bottom ash ponds are operated for settling and storage of bottom ash deposits. Treated coal combustion process waste water is discharged through an overflow outlet structure.

8.2 MAINTENANCE OF THE DAM AND PROJECT FACILITIES

No formal maintenance plan was supplied to Dewberry for review. During the site visit and through discussions on the dam maintenance with plant personnel, it appears that maintenance procedures are adequate. Plant personnel perform routine monthly maintenance inspections. More formal quarterly inspection reports, including required maintenance items, were provided for review (See Appendix A – DOC 15).

8.3 ASSESSMENT OF MAINTENANCE AND METHODS OF OPERATIONS

8.3.1 Adequacy of Operating Procedures

Operating procedures appear to be satisfactory.

8.3.2 Adequacy of Maintenance

Based on assessments of inspection reports and visual observations during the site visit, operation and maintenance activities appear to be adequate.

Flint Creek Power Plant 8-1 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report DRAFT 9.0 ADEQUACY OF SURVEILLANCE AND MONITORING PROGRAM

9.1 SURVEILLANCE PROCEDURES

Monthly inspections are conducted by plant personnel. Inspection reports are submitted to the plant manager for review and the appropriate corrective actions are performed as required.

9.2 INSTRUMENTATION MONITORING

The Flint Creek Power Plant impoundment dikes have four piezometers to monitor ground water levels.

9.3 ASSESSMENT OF SURVEILLANCE AND MONITORING PROGRAM

9.3.1 Adequacy of Inspection Program

Based on the data reviewed by Dewberry, including observations during the site visit, the inspection program is adequate.

9.3.2 Adequacy of Instrumentation Monitoring Program

Based on the data reviewed by Dewberry, including observations during the site visit, the inspection program is adequate.

Flint Creek Power Plant 9-1 SWEPCO Coal Combustion Residue Impoundment Gentry, Arkansas Dam Assessment Report

REPORT FOR THE INSPECTION OF FLINT CREEK ASH POND

ARKANSAS

Submitted To American Electric Power

Submitted By Golder Associates Inc

Report

Distribution 3 –American Electric Power 3 –Golder Associates Inc

Date May 2009 Project No 09390068

10 Golder Associates Inc

3730 Chamblee Tucker Road Atlanta GA USA 30341 Golder Telephone 770 4961893 Associates Fax 770 9349476

May 1 2009 Our Ref 0939006810

American Electric Power AEP

1 Riverside Plaza Columbus OH 432152373

Attn Mr Pedro J Amaya PE Senior Engineer Geotechnical Engineering

RE REPORT FOR THE INSPECTION OF THE BOTTOM ASH POND AT FLINT CREEK STATION BENTON COUNTY ARKANSAS

Dear Mr Amaya

to visual for Golder Associates Inc Golder is pleased submit the attached inspection report the American Electric Power AEP Southwestern Electric Power Bottom Ash Pond at Flint Creek

Station The inspection was performed on March 30 2009 by Mr Michael T Chilson and Mr Rafael 1 Ospina PE under the direction of Mr W Randall Sullivan PE Mr William R Smith and Mr

Gregg Carter PE plant inspection coordinator with AEP were present during the inspection This work was performed in accordance with our proposal dated February 23 2009 and Service Agreement 194677X168 signed March 5 2009

We appreciate this opportunity to provide engineering services to AEP Please do not hesitate to contact of the have further additional one undersigned if you any questions require information or would like to discuss the conclusions presented in this report

Very truly yours GOLDER ASSOCIATES INC

Rafael I Ospina PE W Randall Sullivan PE Lic 8575

Principal and Senior Consultant Principal and Practice Leader

RIOWRSmtcsdp

Distribution

1 Copy American Electric Power

3 Copies Golder Associates Inc

XClientsAmerican Electric Power093006810 Flint Creek Station Dam Inspections250 Final Reports251 March 2009 Ash Pond Inspection ReportFlint Creek Ash Pon dI n spe cti on Re port d ocx

OFFICES ACROSS AFRICA ASIA AUSTRALIA EUROPE NORTH AMERICA AND SOUTH AMERICA May 2009 i 0939006810

DAM DIKE INSPECTION REPORT

BOTTOM ASH POND AT FLINT CREEK STATION BENTON COUNTY AR

INSPECTION DATE March 30 2009

PREPARED BY

Michael T Chilson

REVIEWED BY

Rafael I Ospina PE

APPROVED BY

W Randall Sullivan PE

PROFESSIONAL ENGINEER

SEAL SIGNATURE May 2009 TOC 1 09390068

TABLE OF CONTENTS

SECTION PAGE

INTRODUCTION 1

1.0

BACKGROUND 1

1.1

GENERAL DESCRIPTION DAM 1

1.2

SUMMARY OF VISUAL INSPECTION TERMS 3

2.0

VISUAL OBSERVATIONS 4

3.0

3.1 INFLOW AND OUTFLOW STRUCTURES 4

3.2 UPSTREAM SLOPE 5

3.3 CREST 5

3.4 DOWNSTREAM SLOPE 5

3.5 MONITORING INSTRUMENTATION 6

4.0 ASSESSMENT OF RECENT INSTRUMENTATION DATA 7

5.0 CONCLUSIONS AND RECOMMENDATIONS 8

order

In Following Page 9

LIST OF TABLES

TABLE 5 1 Summary Deficiencies

LIST OF FIGURES

FIGURE 1 1 Site Location FIGURE 1 2 Plan View with Aerial Photograph FIGURE 3 1 Identified Deficiencies

FIGURE 4 1 Section View Piezometric Water Surface

APPENDICES

APPENDIX A Inspection Checklist APPENDIX B Photographs Dam

of APPENDIX C Documentation Provided AEP

Golder Associates May 2009 1 09390068

INTRODUCTION

1.0

Background

1.1

American Electric Power AEP Service Corporation Civil Engineering administers the dam inspection and maintenance program AEP facilities AEP contracted with Golder Associates Inc

Golder complete annual inspection Bottom Ash Pond Flint Creek Station This

to the of the at inspection was completed fulfill part requirements Arkansas National Resources

to in the of the

Commission’s Dam Safety Program and provide AEP evaluation the facility assist

to an of to in the prioritization maintenance activities Golder understands that this structure has not been recently

of inspected This report contains Golder’s observations photographs conclusions and recommendations with inspection certification AEP’s Bottom Ash Pond Flint Creek Station A

of at completed dam inspection checklist was submitted AEP April 6 2009 A copy the checklist

to on of

included Appendix A

is in

Mr Rafael I Ospina P and Mr Michael T Chilson Golder under the direction Mr

E of of W

Randall Sullivan PE with Mr William R Smith PE and Mr Gregg Carter PE AEP visually

of inspected the dam March 30 2009 the time inspection temperature was 60’ s with

on At of the in the partly cloudy skies The severity noted deficiencies and adequacy freeboard and spillway

of the of capacities were assessed based operation dam time visit analytical

on the of the at the of No assessment hydrologic hydraulic performance dam and components was made

of the or of the

The following documentation provided AEP was reviewed and utilized during the preparation

by of this report and included Appendix C

is in

• Flint Creek Power Plant Drawing Number FCX3 Sheets 1 and 2 3 dated 1974 and 1975

• Flint Creek Drawing Number 130301 01 A Bottom Ash Pond Bottom Ash Storage Cell

Location Plan Map dated 2006

1.2 General Description Dam

See Figure 11 location dam and Figure 12 plan view and aerial photograph

for the of the for the

The Bottom Ash Pond divided into two impoundments series The primary upper dam 820

is in is foot long crossvalley dam unnamed tributary Little Flint Creek The secondary lower

on an to the dam a 750 foot long crossvalley dam adjacent first order stream The secondary

is on an impoundment discharges directly Little Flint Creek Reservoir which backs both the

to the up to primary and secondary embankments

Golder Associates May 2009 2 09390068

GENERAL INFORMATION

Dam Reservoir Bottom Ash Pond Flint Creek Station

or at

Owner AEP Southwest Electric Power

Type Dam EarthFill Structure

Date Construction 1978

D S Hazard Not Classified

LOCATION

County Benton County

General Location Approximately miles north Siloam Springs AR

4.5 of

Stream and Basin Unnamed tributary Little Flint Creek Flint Creek Basin

SIZE –PRIMARY DAM

Dam Crest Elevation1 1,155 feet MSL

Maximum Water Level Not Established

Current Water Level2 1,146 feet MSL

Height1 feet

Surface Area acres normal pool

24 at

Reservoir Volume Depth and volume unknown

are

SIZE –SECONDARY DAM

Dam Crest Elevation1 1,155 feet MSL

Maximum Water Level Not Established

Current Water Level2 1,143 feet MSL

Height1 feet

Surface Area 6 acres normal pool

Reservoir Volume Depth and volume unknown

are

Notes 1 Estimated from previously references provided AEP 2 Visually estimated Golder

by by

Golder Associates May 2009 3 09390068

SUMMARY OF VISUAL INSPECTION TERMS

2.0

The summary visual observations presented herein uses terms describe general

of the to the appearance condition observed item activity structure Their meaning understood

or of an or is as follows

CONDITION OF DAM COMPONENT

Good A condition activity that generally better slightly better than what

or is or is

minimally expected anticipated from a design maintenance point

or or of

view

Fair A condition activity that generally meets what minimally expected

or is or

anticipated from a design maintenance point view

or of

Poor A condition activity that generally below what minimally expected

or is is or

anticipated from a design maintenance point view

or of

SEVERITY OF DEFICIENCY

Minor A reference observed deficiency eg erosion seepage vegetation

to an

etc where current maintenance condition below what normal

the is is or

desired but which not currently causing concern from a structure safety

is or

stability point view

Significant A reference observed deficiency eg erosion seepage vegetation etc

to an

where current maintenance program neglected improve

the has to the

condition Usually these conditions have been identified previous

inspections have been corrected

but not

Excessive A reference observed deficiency eg erosion seepage vegetation

to an

etc where current maintenance condition above worse than what

the is or is

normal desired and which may have affected ability observer

or the of the to

properly evaluate structure particular area being observed which

the or or

may a concern froma structure safety stability point view

be or of

Golder Associates May 2009 4 09390068

VISUAL OBSERVATIONS

3.0

See Figure 3 1 the location structures and deficiencies itemized below

for of

3.1 Spillway Structures

The plant inflow channel primary impoundment and principal and emergency spillways

to the the at

primary and secondary impoundments were visually inspected and generally fair condition

the are in

The plant inflow channel about 5 feet from upstream toe and runs the length

is off set the of the primary embankment the right abutment the channel routed through a series 3 culverts one

At is of

which shown Photograph 1 These culverts submerged one both ends indicating they

of is in are at or may undersized The culverts may inset too short width the roadway with some

be be for the of fill overhang overburden above inlets creating a risk blockage event a collapse

of the of in the of of the overhang The culverts could fully inspected due submergence and lack visibility

not be to of

The principal spillway primary impoundment a concrete dropinlet structure The discharge

at the is conduit was submerged exit time visit and could not inspected Some minor

at the at the of be corrosion the metal components chipping the concrete and erosion the embankment contact

of of at were observed and shown Photographs 2 and 3

are in

The emergency spillway primary impoundment shown Photographs 4 and 5 earth

at the in is an cut channel natural ground and was active the time inspection The spillway control section was

in at of designed have a ripraplined weir The ripraplining displaced and sporadic along crest

to is the

Though entire spillway could inspected due unsafe access region greatest flow

the not be to the of near the right bank appeared stable A significant extent undesirable vegetation and trees was

of observed within entrance and exit channels spillway

the of the

The principal spillway secondary impoundment shown Photographs 6 through 8 a

at the in is concrete structure with a series horizontal orifices and weir that discharges open channel

of to an cut

The concrete and metal components structure fair condition Minor algae growth

of the are in partially obstructs flow through trashrack

the

The emergency spillway secondary impoundment shown Photograph 9 a grasslined

at the in is earth channel natural ground was active time inspection signs erosion

cut in It not at the of No of

Golder Associates May 2009 5 09390068

were observed A minor extent undesirable vegetation was observed entrance

of at the to the spillway

Upstream Slope

3.2

The upstream slope depicted Photographs and generally fair condition Minor

in 10 11 is in undesirable vegetation exists both primary and secondary impoundments Minor erosion

on the of the right upstream groin primary embankment was observed The upper third slope

of the of the on the secondary dam steepens about 1v

to 2h

Crest

3.3

The surface crest dam hardpacked earth vehicular access The crests

of the of the is for of the primary and secondary impoundments are fair condition with significant rutting and ponding

in as shown Photograph and

in 12 13

Downstream Slope

3.4

The downstream slope depicted Photographs through 16 fair condition The Little Flint

in in 14 is

Creek Reservoir backs against dam preventing full inspection approximately vertical feet

up the of 12

slope below the water surface The riprap the exposed slope surface above water surface

of on the appears good condition

Undesirable vegetation consisting low brush and trees 6 inches diameter was observed

of to in on

downstream slope mostly among the riprap primary and secondary impoundments

the on the An active seep with immeasurably small and dispersed flow was identified primary impoundment

on the located about 3 feet above the downstream water surface near left abutment No signs

the of sloughing slope instability were observed and movement fine soils Three animal burrows

or no of were identified the left groin primary impoundment middam abutment between

at of the at the the primary and secondary embankments shown Photograph The burrows range size from 6

in 17 in to

inches diameter and 1 4 feet deep the same location groin erosion from surface runoff

18 in to In was observed

Golder Associates May 2009 6 09390068

Monitoring Instrumentation

3.5

Two piezometers were found one each crest primary and secondary embankments The

at the of the piezometer crest primary embankment could opened and was read The

at the of the not be not piezometer crest secondary embankment was broken surface and opening was

at the of the at the the buried shown Photograph The opening was dug and piezometer was read

as in 18 out the

Golder Associates May 2009 7 09390068

ASSESSMENT OF RECENT INSTRUMENTATION DATA

4.0

Figure 41 depicts section view secondary embankment and piezometer reading The

the of the phreatic surface within the secondary embankment appears normal The depth water was 21.1 feet

to below top casing estimated about 1,133.6 feet msl For comparison upstream water

the of at the surface about 1,143.0 feet msl and the downstream water surface about 1,132.1 feet msl The

is is

dam about 1,155.0 feet msl

top of is

Golder Associates May 2009 8 09390068

CONCLUSIONS AND RECOMMENDATIONS

5.0

Table 51 summarizes the deficiencies and recommendations Bottom Ash Pond Flint Creek

for the at

Station

The dam generally fair condition Throughout majority upstream and downstream

is in the of the slopes both primary and secondary impoundments significant undesirable vegetation was

of the observed active seep with immeasurable trickle flow was identified near downstream water

An the surface the primary impoundment Signs animal activity were observed the midslope

of of at abutment

address deficiencies identified the Bottom Ash Pond Golder recommends the following

To the at remedial actions

• Reinspect inflow channel and culverts during a period flow Monitor

the of no for

insufficient capacities and sloughing overburden culvert inlets

of at the

• Regularly clear and maintain trash rack principal spillway secondary

the for the at the

impoundment

• Clear brush and woody vegetation from emergency spillway channel primary

the the at the

impoundment Reinspect the riprap control section the emergency spillway signs

of for of

erosion during a period flow

of no

• Clear the woody vegetation from inlet area emergency spillway channel

the to the at the

secondary impoundment

• Regrade crest positive drainage towards upstream slope

the for the

• vegetation should and maintained less than 6 inches height Clear both slopes

All be cut in

and riprap trees and other undesirable vegetation Seed and mulch areas without riprap

of to

establish a grass cover

• Backfill animal burrows with compacted fill seed and mulch establish grass cover

• Monitor seepage increased flow rates muddy flow and embankment instabilities due

for to

saturated soils

• Open inspect and read piezometer primary embankment Further excavate and

on the

repairreplace outer casing piezometer secondary embankment

the of the on the

Golder Associates May 2009 90939006810

Golder further recommends AEP update the current Emergency Action Plan EAP for the Little Flint

Creek Dam or develop an independent EAP to specifically address emergency situations associated with the Bottom Ash Pond at Flint Creek Station As part of this update AEP should evaluate the impact a failure of the Bottom Ash Pond will have on the Little Flint Creek Dam

GOLDER ASSOCIATES INC

4•116fC5

Michael T Chilson Rafael I Ospina PE

Project Engineer Principal and Senior Consultant

W Randall Sullivan PE

Principal and Practice Leader

Golder Associates F2 f

f ISE•S• •• V April 2009 09390068 10

TABLE 5 1 SUMMARY OF DAM DEFICIENCIES

Component Dam Condition Deficiency Severity Recommendation

Inflow Channel Fair Submerged Culverts Minor Reinspect culverts time no flow monitor for insufficient capacity and

at of

overburden sloughing inlets

Principal Spillways Fair Corrosion Chipping Minor Monitor corrosion on the metal components and chipping the concrete

on the spillway the primary impoundment

Debris Trash Rack Minor Regularly clear and maintain trash rack secondary impoundment

in at

Emergency Spillways Fair Undesirable Vegetation Significant Clear brush and trees fromspillways or reevaluate spillway capacities

Limited Accessibility Minor Reinspect the control section the primary spillway for riprap

displacement and erosion time no flow

at of

Upstream Slope Fair Undesirable Vegetation Minor Clear brush and trees fromriprap and slope Seed and mulch reestablish

a grass cover areas without riprap

Groin Erosion Minor The right upstream groin of the primary embankment showed some erosion

from surface runoff

Crest Fair Rutting Ponding Significant Regrade crest surface for positive drainage towards upstream slope

Downstream Slope Poor Undesirable Vegetation Minor Clear brush and trees fromriprap and slope Seed and mulch reestablish

a grass cover areas without riprap

Groin Erosion Minor The left downstream groin the primary embankment showed some

erosion from surface runoff

Active Seep Minor Monitor seep for increased flow muddy flow and embankment

instabilities due saturated soils

Animal Activity Minor Backfill burrows with compacted fill seed and mulch establish a grass

cover

Monitoring Poor Damage Excessive Open piezometer on the primary embankment inspect for further damage

Instrumentation and take reading Further excavate the piezometer on the secondary

embankment and repairreplace the outer casing

FCADeficiency Table xlsx Golder Associates F2 f

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Inspections

Dike

and REV DATE DES REVISION DESCRIPTION GIS CHK RVW

PROJECT

Dam 2 0 2 AMERICAN ELECTRIC POWER FLINT CREEK BOTTOM ASH POND Miles

09390068 TITLE

Power LOCATOR MAP

Electric

PROJECT No 09390068 10 FILE No FCA Fig11 Locator Flint Creek Ash Pond DESIGN SCALE 1 2 mi REV 0

GIS American MTC 0420 09

CHECK RIO 0421 09

GIS 11 Q Atlanta Georgia REVIEW WRS 0421 09 REFERENCES

USGS 2008 USGS High Resolution State Orthoimagery for Arkansas USGS Sioux FallsSD

200 0 200

Feet

mxd

2Aerial 1

Fig

FCA

PROJECTS

Inspections

Dike

and REV DATE DES REVISION DESCRIPTION GIS CHK RVW

PROJECT Dam AMERICAN ELECTRIC POWER FLINT CREEK BOTTOM ASH POND

09390068 TITLE

Power PLAV VIEW WITH AERIAL PHOTOGRAPH

Electric

PROJECT No 09390068 10 FILE No FCAFig12Aerial

DESIGN SCALE 1200 REV 0

GIS MTC 0420 09

American

CHECK RIO 0421 09

GIS 12 Q Atlanta Georgia REVIEW WRS 0421 09 NOTES

PLACEMENT OF DAM COMPONENTS AND DEFICIENCIES IS APPROXIMATE

200 0 200

V Feet

rJ1 AAL •uRRows

J AT LY A L QrRjo z rR°=• •Rnso• •DcrE O C KzP P

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AMERICAN ELECTRIC POWER FLINT CREEK BOTTOM ASH POND

IDENTIFIED DEFICIENCIES

PROJECT No 0939006810 FILE NOFCAFigj1 Deficiencies

DESIGN SCALE 1200 REV 0 TCIEE L2t`7E GIS MTC 042009 Associates CHECK RIO 042109 31 Atlanta Georgia IREVIEW1 WRS 042109 1160

Elev 1,155.0 Bottom Ash Pond 1150 Secondary Impoundment

Elev 1,143.0 Little Flint Creek Reservoir 1140

msl

feet Elev 1,133.6 Elev 1,132.1 1130

Elevation 1120

1110 Elev 1,110.5

1100

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180

No vertical exaggeration Station feet

Grade Surface

Water Surface

PROJECT Piezometer AMERICAN ELECTRIC POWER FLINT CREEK BOTTOM ASH POND Piezometric Surface

TITLE SECTION VIEW OF PIEZOMETRIC WATER SURFACE SECONDARY IMPOUNDMENT

PROJECT No 09390068 10 FILE No FCADeficiency Table xls

DESIGN SCALE REV 0

MADE BY MTC 04 212009 CHECK RIO 04 222009 41 Atlanta Georgia REVIEW WRS 04 222009 A

Checklist

Appendix

Inspection Golder Associates Inc

3730 Chamblee Tucker Road Atlanta GA USA 30341 Golder Telephone 770 4961893 Associates Fax 770 9349476

April 6 2009 Our Ref 0939006810

American Electric Power Corporation

I Riverside Plaza Columbus OH 432152373

Attention Mr Pedro J Amaya PE Senior Engineer Geotechnical Engineering

RE FLINT CREEK PLANT 2009 ANNUAL DIKE AND DAM INSPECTION LITTLE FLINT CREEK BOTTOM ASH POND ARKANSAS

Dear Mr Amaya

Golder Associates Inc to submit the attached Golder is pleased Inspection Checklist Forms for the

annual safety inspection of the Little Flint Creek Bottom Ash Pond performed on March 30 2009 The inspection was performed by Mr Mike Chilson and Rafael Ospina PE under the direction of Randall Smith and W Sullivan PE Mr WR WG Carter with AEP were present during the inspection

The enclosed forms are to be submitted to the Arkansas Soil and Water Conservation Commission

The full of the will be submitted report inspection to you under a separate cover The work was performed in accordance with our Proposal dated February 23 2009 and Service Agreement 194677X 168

have do hesitate If you any questions please not to contact us

Very truly yours

GOLDER ASSOCIATES INC

Rafael I Ospina PE W Randall Sullivan PE A as 8575 and Senior Consultant Principal Principal and Practice Le4clf

Attachments Inspection Checklists

RIOWRSlio

r TNAr

• Al a cc WR Smith AEP Engineer Geotechnical Engineering EINGINE WG Carter AEP Senior Engineer Region 5 Pant Engineering Chilson Golder Associates Inc M Project Engineer m IJIIJ

XClientsAmerican Electric Power093006810 Flint Creek Station March Dam Inspections200 Reports201 26Q9 A l Fjon• Inspection ReportFlint Creek Ash Pond 10 Day Cover Letter 4609docx

OFFICES ACROSS AFRICA ASIA AUSTRALIA EUROPE NORTH AMERICA SOUTH AMERICA NAME OF DAM Flint Creek Plant Bottom Ash Pond INSPECTION DATE 330 2009

CHECK

EMBANKMENT __ ACTION 1 2 NEEDED

AREA

INSPECTED CONDITION OBSERVATIONS

ITEM

MONITOR INVESTIGATE

REPAIR 1 SURFACE CRACKING None OK

__ 2 CAVE IN ANIMAL BURROW None OK

__ 3 LOW AREA S see 5

__ 4 HORIZONTAL ALIGNMENT OK

__ 5 RUTS AND OR PUDDLES 7 N crest 5 S crest

on on

CREST

__ 6 VEGETATION CONDITION OK

__ 7 8 9 SLIDE SLOUGH SCARP None OK

__ SLOPE PROTECTION Some vegetation riprap

10 in

__ SINKHOLE ANIMAL BURROW Animal activity 23 deep holes near crest N S embankment connectio

11 of

SLOPE

__ EMB ABUT CONTACT Groin erosion right groin N embankment

12 at on

__ EROSION None OK

VEGETATION CONDITION Tall woody vegetation slope and toe

14 on at

__ SLOPE ANGLE Upper 13 S embankment increases slope 1.52.0 1 hv

of in to

UPSTREAM __

ADDITIONAL COMMENTS REFER TO ITEM NO APPLICABLE IF Downstream North N 3 Crest with several low areas holding water regrade positive drainage towards upstream slope for embankment 14 Clear woody vegetation from slopes

10 Clear and maintain vegetation slope and riprap on N Upstream Inspected Rafael Ospina and Mike Chilson Golder Associates Inc South S

by Accompanied Gregg Carter and Smith AEP

by Bill embankment NAME OF DAM Flint Creek Plant Bottom Ash Pond INSPECTION DATE 3 2009

CHECK EMBANKMENT __ ACTION 2 2 NEEDED

AREA

INSPECTED OBSERVATIONS

ITEM

INVESTIGATE

MONITOR REPAIR

WET AREA S NO FLOW Wet area 3 x 3 area N embankment right N S embankment groin

17 on of

__ SEEPAGE None OK

__ SLIDE SLOUGH SCARP None OK

SLOPE EMB ABUT CONTACT OK

__ CAVE IN ANIMAL BURROW Burrows 12 _ deep N S embankment groin 21 6 2

__ EROSION Minor groin erosion between N S embankments

__ UNUSUAL MOVEMENT None OK

__ VEGETATION CONTROL Excessive vegetation among riprap

DOWNSTREAM MID EMBANKMENT GROIN Excessive debris groin

PIEZOMETERS OBSERV WELLS Well S embankment broken Could not open well N embankment

27 on on

__ __ STAFF GAUGE AND RECORDER NA None observed

28 WEIRS NA None observed

29 SURVEY MONUMENTS NA None observed

30 DRAINS NA None observed

FREQUENCY OF READINGS Frequency readings scheduled AEP

32 of by

LOCATION OF RECORDS Records kept with AEP

INSTRUMENTATION

ADDITIONAL COMMENTS REFER ITEM NO APPLICABLE

TO IF

21 Backfill and compact burrows

25 Clear debris from groin between N S embankments and monitor progressive erosion

for 27 Repair broken well Open and measure well N embankment

on 24 Clear vegetation from riprap NAME OF DAM Flint Creek Plant Bottom Ash Pond INSPECTION DATE 330 2009

CHECK

SPILLWAYS __ ACTION 1 1 NEEDED

AREA

INSPECTED CONDITION OBSERVATIONS

ITEM

REPAIR

MONITOR INVESTIGATE SLIDE SLOUGH SCARP None OK

__ EROSION None See note below

__ __ VEGETATION CONDITION Excessive vegetation channel

A 53 in

__ N DEBRIS Excessive vegetal debris channel

54 in

CHANNEL trees ERODIBLE APPROACH AREA Stand approach area

of in

56 SIDEWALLS NA

57 CHANNEL FLOOR

58 NA UNUSUAL MOVEMENT NA

CHANNEL APPROACH AREA

60 NA WEIR OR CONTROL NA

ERODIBLE

61 DISCHARGE AREA NA

NON DRAINS NA

PRINCIPAL

64 INTAKE STRUCTURE NA

65 TRASHRACK NA A 66 STILLING BASIN NA N 67

DROP INLET

69 ADDITIONAL COMMENTS REFER TO ITEM NO APPLICABLE

52 Could not fully inspect upper channel due limited access Excessive debris and active discharge time inspection prevented safe access

to at of Clear channel time flow and reinspect erosion

at of no for NAME OF DAM Flint Creek Plant Bottom Ash Pond INSPECTION DATE 3312009

OUTLET WORKS CHECK V ACTION w 1 of 1 NEEDED W 0 W w d z 2 CONDITION OBSERVATIONS 0

0 > w

70 INTAKE STRUCTURE Lower and Upper structures OK minor erosion at embankment contact

71 TRASHRACK Lower trash rack with excessive algae growth 72 STILLING BASIN OK F073 PRIMARY CLOSURE NA U 74 SECONDARY CLOSURE NA

75 CONTROL MECHANISM 0 Weirs functional 76 OUTLET PIPE Could not lower lower inspect upper pipe submerged in pond no pipe w 77 OUTLET TOWER NA

H 78 EROSION ALONG DAM TOE OK

O 79 SEEPAGE None OK

80 UNUSUAL MOVEMENT None OK 838281 ADDITIONALCOMMENTS REFER TO ITEM NO IF APPLICABLE f > • sr

71 Periodically clear algae from trash rack •

ELISE PR FESSTONAL

Iw r r

9 ••

•• c 8 FLINT CREEK ASH POND MARCH 2009 INSPECTION

CHAPTER 16 DAM INSPECTION AND MAINTENANCE CHECKLIST

THE EMBANKMENT

Key things look for Any evidence movement either within the dam itself ends

to of at its the material on which rests and excessive surface erosion or other damage the

or in it to embankment or excessive seepage the dam overgrown with underbrush or trees

SURFACE CRACKS

Yes No Remarks Maintenance Tips

X Are there any May indicate movement Should be evaluated by a

surface cracks within the dam professional engineer

X there any Dam its foundation may Should be evaluated by a

Is or unusual movement be unstable professional engineer

or cracking at beyond the

or toe

SURFACE EROSION

Yes No Remarks Maintenance Tips

x there erosion on severe rapid a severe and progressive

Is If or If upstream face from wave serious problem protect upstream face with

action or changes pool riprap other form

in or of level wave protection

x there erosion Erosion any sort a Improve grass cover

Is of is

from runoff either rills problem as tends reshape embankment

it to to

gullies bare areas worsen with time not improve drainage pattern

or if See Inspection Checklist corrected Items

12 22

x there erosion Any erosion serious as Try keep types

Is is to all of

from traffic people will get worse with time traffic to a reasonable

it if

animals vehicles not corrected level Keep vehicles off

dam Stabilize crest roads

to prevent rutting Prohibit

recreational vehicle traffic on slopes Keep livestock

off dam Fill existing ruts

in or eroded areas and reseed

161 EMBANKMENT continued ANIMAL BURROWS

Yes No Remarks Maintenance Tips

x Are there any May provide passageways Fill burrows with earth or

animal burrows for water into through otherwise block entry Try

or the keep woodchucks

dam to See Inspection muskrat and beaver away Checklist Item from the dam

DEPRESSIONS

Yes No Remarks Maintenance Tips

x Are there May have resulted from pronounced

If or depressed areas on the slope failures progressive must be

or dam settlement or even piping evaluated by a professional engineer

PIPING

Yes No Remarks Maintenance Tips

x there any Piping internal erosion Piping always a serious

Is is is evidence piping This within an embankment condition which can lead

of or condition evidenced by a the progressive removal to failure the dam A

is of of muddy flow through the soil particles adjacent piping condition must be

dam and the formation leaks through a soil mass evaluated by a

of soil deposits beyond the professional engineer dam and depressions on

its slopes

x Does the crest Crest movement may Must be evaluated by a appear have shifted or indicate a stability problem professional engineer

settled excessively Look However some settlement

for cracks the a new fill such an

in of as embankmentand associated embankment dam

is structures Compare normal alignment with plans they

if are available

162 EMBANKMENT continued PIPING continued

Yes No Remarks Maintenance Tips

x the upstream face Effectiveness lessened Restore riprap as

If is if

protected by riprap riprap has slipped out necessary keep free

it is is of of good condition Riprap place has been trees and bushes

in a layer facing or undermined has

is or protective mound stone become overgrown with

of random size pieces brush

in randomly placed prevent

to erosion scour

or sloughing an of See Inspection Checklist embankment or structure Item

there riprap Has riprap been displaced Restore riprap as

If is in discharge channels or or overgrown necessary keep free

in of the plunge pool trees and bushes downstream good

in it is condition NA

drainage Drainage along abutments Riprap or other form

If of channels ends often causes gullying slope protection should be

at of if embankment are protected there no protection used as necessary

is with riprap good

in it is condition NA See Inspection Checklist Item

x there riprap Restore as necessary

If is in miscellaneous areas on downstream slope on crest etc good

in it is repair See Inspection Checklist Item 24

163 EMBANKMENT continued ALIGNMENT

Yes No Remarks Maintenance Tips

x Does the crest Crest movement may Should be evaluated by a

appear have shifted indicate a stability problem professional engineer

to or

settled excessively Look However some settlement

for cracks the a new fill such as an

in of embankmentand associated embankment

dam is structures Compare normal alignment with plans they

if are available

SEEPAGE

Yes No Remarks Maintenance Tips

there are any Check plans for the Keep drains clear any

If of

drains to collect and presence drains and blockages and assure

of remove seepage are they search the dam see proper operation

to if operating properly any others are present

there are Foundation drains serve to Open outlets such

If to

foundation drain outlets collect seepage passing drains they have become

if are they clear and flowing through the dam and covered clogged

conduct away from the

it NA embankment

x Are there wet spots Some seepage normal Observe seepage areas

is or areas on the for an earth dam Be periodically to detect downstream face the concerned appears changes the amount

it at if to in of toe beyond the dam be excessive a lot moisture new flows

or of or Such spots are often standing water very soft muddy flows the upper

indicated by a change and marshy areas limit seepage fairly

in of is

color type vegetation evidence a seepage line high on the downstream

or of of such as from grass to high on the downstream face the dam may be

cattails See Inspection face unstable

Checklist Item

164 EMBANKMENT continued SEEPAGE continued

x Are there seeps Flowing seeps springs Monitor seepage closely

or or springs with flowing water may indicate problems for any changes amount

Look closely for these and should be periodically rate extent clarity

at or the ends the dam monitored for changes Excessive turbid

of in or around any pipes passing rate of flow or muddy flow seepage or marked through the embankment Creation an increases rate

of in of on downstream face the impoundment often causes seepage should be

at toe the dam and changes the water table evaluated by a

of in beyond and the base nearby professional engineer

at of trees on near or below the dam

x there swamp Swamp type vegetation Cut frequently make

Is or marsh type vegetation on indicates the presence observation of the area

of downstream face or seepage easier Such growth can beyond the dam cattails hide problems tall grass etc

VEGETATION

x the dam One the most frequent Keep embankment faces

Is of overgrown with trees problems and highly free trees and

of and underbrush undesirableRoots may underbrush by periodic

or damage the embankment mowing Remove existing See Inspection and allow water pass trees and saplings and

Checklist Items into through Trees establish and maintain a

or it

14 may be uprooted a good grass cover on the and in

24 storm and breach the dam dam

165 EMBANKMENT contined OVERTOPPING

x Has the dam ever Past overtopping may Restore eroded areas

or been overtopped by water have resulted erosion other damage done the

in of to flowing over it the crest and downstream dam by overtopping face the dam Consider enlarging the

Overtopping indicates that emergency spillway the emergency spillway lowering the normal pool

is probably too small level allow more storage

to capacity during floods

perhaps raising the height of the embankment

decrease the possibility

of future overtopping Consult a professional engineer

MODIFICATIONS

x Has there been any Inappropriate or unsuitable Dams that have been modification the modifications can appreciably modified since

of embankment such as drastically affect the safety construction should be raising the crest changing of a dam even one that evaluated for stability by a the shape or size the may have originally been professional engineer

of principal spillway the properly designed and

or emergency spillway or constructed changing the shape or size of the embankment

166 THE PRINCIPAL SPILLWAY

Yes No Remarks Maintenance Tips

x Can water flow into The riser intake structure Install a trash rack one

if is the principal spillway channel should be free not already place

or in without difficulty as of trash or other blockage Periodically clear trash intended when rack any accumulated

of constructed See Inspection Checklist Item debris

x outlet pipe Flows passing through the Keep outlet pipe plunge

Is or discharge channel clear spillway should not erode basin and all other outlet and open allow the free or otherwise damage the works clear and good

to in passage the principal dam repair

of spillway discharge

x the primary Such dam features as the Repair and maintain as

Is spillway structure good principal spillway require appropriateinsure the in continuedto condition check concrete continued maintenance useful life the

of wood and metal portions like any other structure dam for damage

or deterioration

x Does the lake have a Lowering a lake may be Check plans search

or drain that can be used necessary the dam dam for emergency drain

to if lower an emergency begins develop system

in it to problems

there an Drain valves and other Maintain system so that

If is it emergency drain mechanisms should can be used an

it is in known be working receive sufficient emergency Normally the

to in condition Danger a maintenance to insure that pool behind an earth

If drain has not been used they remain working embankment dam should

in for a long time may be order not be lowered a rate

at of

it possible open but not more than 1 inch per day

to it close thus draining the

it lake NA

there are other Such devices are vital to Repair and restore

If if gates valves the effective and safe necessary and maintain

or in operating equipment operation the dam an operable condition

of are these working

in condition NA

167 THE EMERGENCY SPILLWAY

Yes No Remarks Maintenance Tips

x Can water flow into To be effective all portions The approach channel the emergency spillway of the spillway channel should be kept free

of without difficulty as should be clear and trash underbrush other

or intended when unobstructed blockage constructed

x the discharge Spillway flows must be Clear as necessary

Is channel clear and open effectivelyconducted away

to allow the free passage from the dam

of the emergency spillway discharge See Inspection Checklist Items

54 53

x the emergency A berm often Reshape dam necessary

Is is if spillway constructed constructed keep take care this

in to to of such a way that its flows spillway flows from problem will not erode other encroaching on the portionsthe dam embankment

x the emergency Spillway erosion a Restore any erosion gullies

Is is spillway good condition common problem or eroded areas Provide

in overall check for erosion channel protection riprap within the channel concrete etc necessary

if adequacy grass cover eliminate recurring

of to etc See Inspection Checklist Item 52 problems

THE RESERVOIR AREA

Yes No Remarks Maintenance Tips

x serious wave Some minor erosion along Critical shoreline areas can

Is erosion occurring along the a shoreline be be protected with

is to shoreline expected vegetation or some

in other manner

x a lot sediment This may occur as a result Dredging may be required

Is of entering the impoundment of construction or to restore the lake or has this happened the agricultural activity the

in in past Bottom Ash watershed

168 RESERVOIR AREA continued

x Does the nature Intensive agricultural or Problems this nature are

of of the land surrounding the development activities often complex and may be

lake or its use present any the watershed may beyond the owner’s direct

problems precipitate problems control associated with surface

runoff other difficulties

x there any A large landslide into a Suspected evident

Is or evidence of landslides lake can subject a dam problemsthis type should

or to of

instability on the slopes overtopping or other be investigated by a around the reservoir damage professional engineer

or engineering geologist

DOWNSTREAM CHANNEL

Yes No Remarks Maintenance Tips

x the downstream The channel below a dam Clear downstream channel

Is channel free often a neglected area necessary

of is if obstructions so that water

a flood will not back up

in against the toe the

of dam

WATERSHED AREA

Yes No Remarks Maintenance Tips

x Have there been Intensive agricultural or Problems this nature are

of any major modifications or developmentactivities the often complex and may be

in significant changes the watershed may precipitate beyond the owner’s direct

in watershed drainage area problems associated with control Appeals to existing such as new urban greater surface runoff regulations dealing with

or developments shopping other difficulties erosion prevention centers housing projects pollution control etc may clear cutting woodlands be helpful

of other basic changes

or in land use

169 THE DOWNSTREAM AREA

Yes No Remarks Maintenance Tips

__ the dam should Consider the number of the If Personally inspecting fail would loss of life or occupied homes or area that would be affected extensive businesses will be useful property damage downstream in be likely their distance from the determining who needs to and their dam distance be alerted in an

am oreaK anaiys from and elevation above emergency Topographic As to be perforrr the streambed Consider maps prepared by the US also losses are also valuate the imps potential in Geological Survey and for this the Flint Creek property disruption of useful purpose

facilities ie roads ervoir downstre railroads or utilities

Ell _ Do you have on file Prior planning for an Any list of phone numbers the current invaluable or other information to be

telephone emergencyis in numbers of terms of losses used an any persons mitigating in emergency

living or in areas When a dam failure should be checked for working is downstream from the too late to and

is dam imminent it accuracy updated as well the who to insure that

as telephone begin wondering is periodically numbers of those located downstream and the information remains responsible for facilities how they can be reached current that would be affected such as highways or public utilities

® _ Do you have on file In an emergency certain The Arkansas Soil and the current telephone functions such as Water Conservation numbers of local compelling the evacuation Commission and the local authoritieswho should be of an area can be Emergency Services informed the dam those Coordinator can offer

if is performed only by endangered such as the with the legal authority to guidance for preparing an do so sheriff county emergency warning plan if administrator or needed Such a plan emergency services should be filed with local coordinator authorities

1610 B ofDam

Appendix

Photographs E

a m

v N REV DATE DES REVISION DESCRIPTION GIS CHK RVW E PROJECT AMERICAN ELECTRIC POWER FLINT CREEK BOTTOM ASH POND

Co 0 TITLE 0

0 LOCATION OF PHOTOGRAPH

LL7

PROJECT FILE No No 0939006810 FCAFigBAPholograph•

DESIGN SCALE 200 REV 0

GIS MTC 042009 Associates CHECK RIO 042109 B1 Atlanta Georgia REVIEW WRS 0421109 1 Inflow Channel Fair condition

Culverts channel

in the are submerged both ends indicating

at culverts may undersized

2 Principal Spillway – Primary Impoundment

Fair condition

Minor erosion embankment

at contact

3 Principal Spillway Weir – Primary Impoundment

Fair condition

Minor chipping concrete and

of the

corrosion metal components were

of observed

Golder Associates 4 Emergency Spillway Control Section –Primary Impoundment

Poor condition due significant

to riprap displacement

The emergency spillway was

activating time inspection

at the of The riprap control section

has significant displacement

5 Emergency Spillway Channel – Primary Impoundment

Poor condition due significant

to undesirable vegetation

Significant undesirable vegetation

obstructs channel

6 Principal Spillway – Secondary Impoundment

Fair condition

Minor algae growth partially

obstructs flow through trash rack

the

Golder Associates 7 Principal Spillway Weir – Secondary Impoundment

Fair condition

Concrete orifice and weir system

8 Principal Spillway Discharge Channel – Secondary Impoundment

Fair condition

Channel appears stable

9 Emergency Spillway – Secondary Impoundment

Fair condition

Minor extent woody vegetation

partially obstructs entrance

Golder Associates 10 Upstream Slope – Primary Impoundment

Fair condition

Undesirable vegetation slope

11 Upstream Slope – Secondary Impoundment

Fair condition

Undesirable vegetation slope

on Slope steepens near crest

12 Crest – Primary Impoundment

Fair condition

Significant rutting and ponding

on surface

Golder Associates 13 Crest– Secondary Impoundment

Fair condition

Significant rutting and ponding

on surface

14 Downstream Slope – Primary Impoundment

Fair condition

Undesirable vegetation

15 Downstream Slope – Primary Impoundment

Active seepage 3 vertical feet above

downstream water surface with

immeasurably small and dispersed flow

Golder Associates 16 Downstream Slope –Secondary Impoundment

Fair condition

Undesirable vegetation

17 Left Groin –Primary Impoundment middam abutment between

at primary and secondary embankments

Fair condition

Three animal burrows were

identified the middam abutment

on approximately 6 inches

to 18 in diameter and 1 4 feet deep

18 Piezometer – Secondary Impoundment

Poor condition

The outer casing broken top

is at the

and the piezometer was buried

Golder Associates AEP Cby

Provided

Appendix

Documentation

DAM DIKE INSPECTION REPORT

PRIMARY SECONDARY ASH POND DAMS AT FLINT CREEK POWER PLANT BENTON COUNTY AR

INSPECTION DATE September 16 2009

PREPARED BY DATE

REVIEWED BY ti DATE

Gary F Zy h PE

APPROVED BY DATE

SATE OF

fI AR AS

REGISTERED PROFESSIONAL ENGINEER

•j No 135111 Al <<•4M R5j••1

PROFESSIONAL ENGINEER

SEAL SIGNATURE TABLE OF CONTENTS

SECTION PAGE

INTRODUCTION 1

SUMMARY OF VISUAL OBSERVATIONS 2

SPILLWAY STRUCTURES 4

UPSTREAM SLOPES 5

CRESTS 5

DOWNSTREAM SLOPES 6

MONITORING INSTRUMENTATION 7

ASSESSMENT OF RECENT INSTRUMENTATION DATA 7

CONCLUSIONS AND RECOMMENDATIONS 8

APPENDICES

APPENDIX A Inspection Photographs

APPENDIX B Arkansas Dam Inspection and Maintenance Checklist

APPENDIX C Design Drawings APPENDIX D Guidelines for Herbicide Use on Earthen Dams

ii INTRODUCTION

AEPSC American Electric Power Service Corporation Civil Engineering administers the

Dam Inspection and Maintenance Program DIMP at AEP facilities As part of the DIMP

dike staff from the geotechnical engineering section conducts dam and inspections annually

Mr William R Smith PE performed the 2009 inspection of the primary and secondary ash

at Power Plant This of the and an pond darns the Flint Creek report is a summary inspection assessment of the general condition of the facility Appendix A presents photos that were taken during the inspection Appendix B contains completed and blank dam inspection and maintenance checklists on forms provided the State of Arkansas Appendix C provides design

by drawings of the dams and their appurtenances

Mr W Greg Carter of AEP Plant Engineering Region 5 joined Mr Smith in the inspection

Mr Damon Robertson maintenance superintendent at the Flint Creek Plant was the facility contact The inspection was performed on September 16 2009 Weather conditions were

mid 70s overcast with light winds light rain and temperatures in the low to °F

Figure 1 provides a plan view and aerial photograph of the primary and secondary ash pond darns and appurtenances Drawing FCX3 Sheet I in Appendix C provides a plan view of the design of the dams and appurtenances The ash ponds are divided into two

ash dam 820foot impoundments in series The primary upper pond is an long crossvalley

The dam 750foot dam on an unnamed tributary to Little Flint Creek secondary lower is a long crossvalley dam on an adjacent first order stream The secondary impoundment

to the Little Flint Creek which to both the discharges directly Reservoir is adjacent primary and secondary ash pond embankments

GENERAL INFORMATION

Dam or Reservoir Primary and Secondary Ash Pond Dams at Flint Creek

Power Plant

Owner AEP Southwestern Electric Power Co

Type of Dam EarthFill Structure

Page 1 of 9 Date of Construction 1978

DS Hazard Not Classified

LOCATION

County Benton County

General Location Approximately 45 miles north of Siloam Springs AR

Little Flint Flint Creek Basin Stream and Basin Unnamed tributary to Creek

SIZE PRIMARY DAM

Dam Crest Elevation 1155 feetMSL

Maximum Water Level Not Established

Current Water Level2 1146 feetMSL

Height 45 feet

Surface Area 24 acres at normal pool

Reservoir Volume Depth and volume are unknown

SIZE SECONDARY DAM

Dam Crest Elevation 1155 feetMSL

Maximum Water Level Not Established

Current Water Level 1143 feetMSL

Height 35 feet

Surface Area 6 acres at normal pool

Reservoir Volume Depth and volume are unknown

Notes 1 Estimated from AEP construction drawings 2 Visually estimated during inspection

SUMMARY OF VISUAL OBSERVATIONS

The summary of the visual observations presented herein uses terms to describe the general

Their appearance or condition of an observed item activity or structure meaning is understood as follows

Page 2of9 CONDITION OF DAM COMPONENT

Good A condition or that better or better than activity is generally slightly

what or from a design or

is minimally expected anticipated

maintenance point of view

what Fair or A condition or activity that generally meets is minimally

of view Satisfactory expected or anticipated from a design or maintenance point

condition that below what Poor A or activity is generally is minimally

expected or anticipated from a design or maintenance point of view

SEVERITY OF DEFICIENCY

Minor A reference to an observed deficiency eg erosion seepage

maintenance condition below vegetation etc where the current is

what normal but which not concern

or desired is currently causing

from a structure safety or stability point of view

Significant A reference to an observed deficiency eg erosion seepage

vegetation etc where the current maintenance program has neglected

to improve the condition Usually these conditions have been

identified in previous inspections but have not been corrected

Excessive A reference to an observed deficiency eg erosion seepage

where the current maintenance condition above or vegetation etc is

than what normal and which have affected the worse is or desired may

ability of the observer to properly evaluate the structure or particular

area being observed or which may be a concern from a structure safety

or stability point of view

Page 3 of 9 Spillway Structures

The at the a concrete structure with principal spillway primary impoundment is dropinlet stop logs to control the crest elevation Significant blockage of the inlet with tree branches and other vegetative debris was noted Some minor corrosion of the metal components and

observed A view of the blocked inlet shown in chipping of the concrete was also partially is

Photo 1 The principal spillway also had significantly high vegetation including woody

around as shown in Photo 2 The has cleared the vegetation growing it plant reportedly blockage from the spillway inlet and controlled the growth of vegetation since the time of inspection

The the an incised channel in natural emergency spillway at primary impoundment is ground and was active at the time of inspection The spillway was observed to be in generally fair to

condition attributable undesirable poor condition This was primarily to excessive vegetation growth including a number of trees over 20 feet in height observed within the entrance and exit channels of the spillway as shown in Photo 3 The spillway control section was designed to have a ripraplined weir as shown on Drawings FCX3 Sheet 1 and

Sheet 2 The observed to be and the weir FCX29riprap lining was displaced sporadic along Though the entire spillway could not be inspected due to unsafe access the region of greatest flow near the right bank appeared stable The plant has reportedly cleared the vegetation from the emergency spillway and controlled further growth since the time of inspection

The principal spillway at the secondary impoundment shown in Photos 4 through 6 consists of a concrete outlet structure with a series of horizontal orifices and a weir that discharges to an open cut channel The concrete and metal components of the outlet structure were observed and noted in fair condition Significant growth of woody vegetation including one tree over 15 feet in height was observed adjacent to the outlet structure Minor growth of woody vegetation was observed growing just upstream of the weir The discharge channel was in fair and stable condition The plant has reportedly cleared the vegetation from the spillway and controlled further growth since the time of inspection

Page 4 of 9 The the shown in Photos 4 and an emergency spillway at secondary impoundment 5 is incised channel natural and was active at the time of The

in ground inspection spillway control section was designed to have a ripraplined weir as shown on Drawings FCX3 Sheet

observed be and 1 and FCX29 Sheet 2 The riprap lining was to displaced sporadic along the upstream side of the weir The downstream side had been recently excavated in preparation for reconstruction activities No signs of erosion were observed

Upstream Slopes

The upstream slope of the primary dam was observed to be in generally fair to poor condition

number of in 20 feet because of excessive undesirable vegetation including a trees over in height as shown in Photos 7 and 8 Substantial portions of the slope and groins at the primary dam were not observable because of the significantly to excessively overgrown

noted The vegetation No observable signs of sloughing erosion or slope instability were upstream groins of the primary dam are depicted in Photos 7 and 9 The plant has reportedly cleared the vegetation from the slope and groins and controlled further growth since the time of inspection

The upstream slope of the secondary dam was observed to be in generally fair condition All of the excessive woody vegetation had been recently cut as depicted in Photo 10 but

The significant vegetation was observed growing through the riprap slope protection riprap itself appeared to be in good condition but the condition was not observable in some areas because of dense No observable of vegetation growing through it signs sloughing erosion or slope instability were noted The upstream groins of the secondary dam with significantly high vegetation are shown in Photos 11 and 12 The plant has reportedly cleared the vegetation from the slope and groins and controlled further growth since the time of inspection

Crests

The of the of the dam earth and used for vehicular The surface crest is hardpacked access

noted in fair crests of the primary and secondary impoundments were condition with no evidence of misalignment settlement or cracking but with minor rutting and ponded water

Page 5 of 9 as shown in Photos 13 and 14 The plant has reportedly regraded the crests at both dams for

the and of positive drainage toward the upstream slopes and eliminated rutting ponding water

since the time of inspection

Downstream Slopes

The downstream slope of the primary dam was noted to be in fair condition No apparent

but substantial of the signs of sloughing erosion or slope instability were observed portions

few covered slope were obscured by significantly overgrown vegetation and a areas were by

vegetation that was excessively overgrown Views of the slope and groins at the primary

dam are shown Photos 15 2 1 The Little Flint Creek Reservoir also known as

in through

Lake Flint Creek backs up against both the primary and secondary dams This prevented

inspection of approximately 21 vertical feet of slope at the primary dam that was below the

water surface at the time of inspection

in The riprap on the exposed slope above the water surface was apparently good condition

but the condition was not observable in some areas because of significantly to excessively

as shown in the The has overgrown vegetation growing through it photos plant reportedly

cleared the vegetation from the slope and groins and controlled further growth since the time

of inspection

An active seep located during a March 2009 inspection of the downstream slope of the

primary dam near the left groin and the water surface was searched for but could not be

found and was apparently dry One group of animal burrows was identified at the left

downstream of the and shown in Photo 20 An active groin primary impoundment is

the left of the dam the ingroundbeehive was noted on the downstream slope at quarter near

crest Photo 21 shows the hive and its active use Plant personnel began the application of

insecticide at the hive during the inspection The plant has reportedly backfilled the group of

animal burrows and eliminated the beehive since the time of inspection

Page 6 of 9 The downstream slope of the secondary dam was noted to be in fair condition No apparent

but of the signs of sloughing erosion or slope instability were observed some portions slope were obscured by significantly overgrown vegetation Views of the slope and groins at the secondary dam are shown in Photos 22 through 25 The inundation of the dam by the Little

Flint Creek Reservoir prevented inspection of approximately 10 vertical feet of slope that was below the water surface at the time of inspection

of the above the water surface in The riprap on the exposed slope secondary dam was apparently good condition but the condition was not observable in some areas because of

overgrown as shown in the All of the significantly vegetation growing through it photos

had been demonstrated large trees on the slope except one evergreen recently cut as in

Photos 23 and 24 These two photos were taken backtoback at the mid slope area and together show most of the slope The downstream groins showed no signs of erosion but the left groin had a substantial amount of significantly overgrown vegetation growth as shown in

Photo 25 The plant has reportedly cleared the vegetation from the slope and groins and controlled further growth since the time of inspection

Monitoring Instrumentation

Three piezometers were found at the ash pond dams two at the crest of the primary dam and one at the crest of the secondary The piezometers at the primary dam were in fair condition

The piezometer at the crest of the secondary dam was broken at the surface and the opening was buried under a few inches of soil The opening was dug out as shown in Photo 26 and the piezometer was read The plant has reportedly had the piezometer repaired since the time of inspection

ASSESSMENT OF RECENT INSTRUMENTATION DATA

The depths to the water surface and to the bottoms of the three piezonleters at the ash pond dams were measured during the inspection The piezometer toward the right side of the primary dam had a depth to water of 2207 ft and a depth to bottom of 5271 ft The bottom was noted as soft indicating some sediment buildup at the piezometer bottom The depth to water of the piezometer toward the left side was 2205 ft and the depth to bottom was 4269

Page 7 of 9 ft The bottom in this piezometer was also soft Using the design top elevation at the crest of

11550 ft gives a water elevation of approximately 11329 ft at the crest of the primary dam This phreatic surface appears normal given that the upstream water surface was at about El 11460 ft and the downstream water surface was at El 11324 ft

The piezometer on the crest of the secondary dam had a depth to water of 2164 ft and a depth to bottom of 4386 ft The bottom was noted as soft Using the design top elevation at the crest of 11550 ft gives a water elevation of approximately 11334 ft at the crest of the secondary dam This phreatic surface within the secondary dam appears normal given that the upstream water surface was at about El 11430 ft and the downstream water surface was at El 11324 ft

CONCLUSIONS AND RECOMMENDATIONS

Based visual and review of the instrumentation information on our inspection available it is concluded that the primary and secondary ash pond dams were generally in fair condition at the time of inspection with no signs of distress that would indicate possible instability excessive settlement misalignment sloughing or cracking of the dams

A summary of our recommendations for general maintenance and continued monitoring as well recommendations for remedial as follows as any activities is provided

Recommendations for General Maintenance and Monitoring Activities

Regularly clear any blockage and maintain free flow to the principal spillway inlets at

the primary and secondary dams

Regularly control any brush andor woody vegetation growth at the emergency

spillway channels at the primary and secondary dams

Maintain least twice At where not vegetation by cutting at per year areas it is

feasible to use mowing equipment control vegetation with weed trimmers power

brush cutters or similar equipment General vegetation control should extend to 25

feet beyond the groins Appendix 1 contains recommended guidelines on herbicide

use to control the growth of brush and woody vegetation near earthen dams

Page 8 of 9 Maintain at without to erosion a grass cover areas riprap prevent

Backfill any noted animal burrows with compacted fill seed and mulch to establish

basis grass cover on a regular

Monitor the riprap control section of the emergency spillways for signs of erosion

during periods of no flow

The dams should be inspected by plant personnel quarterly and within 24 hours of

unusual events such as seismic activity or a significant storm event with the

inspection documented in accordance with AEP Circular Letter CIMCL010C For

the of these a storm event defined as a storm that purpose inspections significant is

results in three inches or more of rainfall in 24 hours A blank copy of inspection

forms the Arkansas Soil and Water Conservation Commission provided by is

provided at the end of Appendix B

Recommendations for Remedial Activities

None

Submitted By

American Electric Power Service Corporation

CiviVGeotechnical Engineering

E 5• AT OF • A1•l R AS ttREGISTEREDis a William R Smith PE PROFESSIONAL Geotechnical Engineer ENGINE E R AEP Service Corporation ® ®e Arkansas Certificate 13511 No13511 ••`ol M R BOP

VL Pedro Amaya PE Mgr Geotechnical Section

AEP Service Corporation

Page 9 of 9 PPP ni

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inlet and Photo 1 Primary ash pond principal spillway with significant blockage at

minor corrosion of steel and chipping of concrete components

Photo 2 Primary ash pond principal spillway with significantly high and woody

vegetation growing adjacent to it Photo 3 Pritnai rnd emergency spillway active with

and rprn ilaced from the weir crest weir with minor of Photo 5 Secondary ash pond principal spillway growth woody

vegetation and active emergency spillway prepared for reconstruction

channel in Photo 6 Secondary ash pond principal spillway discharge was

fair and stable condition dam with excessive and Photo 7 Upstream slope and right groin area of primary

undesirable vegetation

Photo 8 Upstream slope of primary dam looking right with excessive and

undesirable vegetation Photo 9 Upstream left groin of primary dam with some recently cut woody

vegetation and some remaining at left of photo

Photo 10 Upstream slope of secondary dam with recently cut tree at left and

significant vegetation growing through riprap dam with Photo 11 Upstream right groin of secondary significantly overgrown

vegetation growing through riprap

Photo 12 Upstream left groin of secondary darn with significantly overgrown

vegetation with minor Photo 13 Crest of primary dam from near right abutment looking left

rutting and ponded water

Photo 14 Crest of secondary darn from near left abutment looking right with minor

rutting and ponded water with minor Photo 15 Downstream right groin at primary dam in fair condition a

amount of overgrown vegetation growing through the riprap

Photo 16 Downstream left groin of the primary dam with significantly to excessively

overgrown vegetation growing through the riprap Photo 17 Downstream left groin of the primary dam looking upstream with

significantly to excessively overgrown vegetation

Photo 18 Overview of downstream slope of primary dam in fair condition Photo 19 Downstream slope of primary dam with significantly overgrown vegetation

and recently cut tree in foreground

of Photo 20 One group of animal burrows was observed at the downstream left groin

the primary dam Photo 21 An active inground beehive was observed on the downstream slope of the

primary ash pond dam

Photo 22 Downstream right groin at secondary dam with significantly overgrown

vegetation Photo 23 Downstream slope of secondary ash pond dam looking right with recently

cut tree in foreground and some significantly overgrown vegetation

X W

Photo 24 Downstream slope of secondary darn looking left with one large tree the remaining and significantly high vegetation growing through riprap Photo 25 Downstream left groin at secondary dam with significantly overgrown

vegetation preventing a thorough inspection

Jim

dam buried under a few Photo 26 The piezometer at the crest of the secondary was

inches of soil dug out and read APPENDIX

Arkansas Darn Inspection and Maintenance Checklist ACTION

NEEDED

9162009 VO VO

CHECK

DATE

INSPECTION

plant

per

riprap

plant

per

inspection

through

plant plant

after

per per

inspection

growing

OBSERVATIONS

after

controlled

WRS inspection inspection

vegetation

shortly

OK OK OK OK OK

after after of

excess

1of2

but

cleared

shortly shortly control

poor

observed observed observed observed observed

EMBANKMENT

INSPECTED

None Repaired None Repaired Good None None None Fair

OK Continue Vegetation

Pond

Ash

APPLICABLE

BURROW

SCARP

Bottom PUDDLES

CONDITION CONDITION

ALIGNMENT

CONTACT

ANIMAL

CONDITION

CRACKING

ANIMAL ITEM

PROTECTION

SLOUGH

Primary IN TO

ANDOR

AREAS

SURFACE CAVE LOW HORIZONTAL RUTS SLIDE SLOPE SINKHOLE EMBABUT EROSION VEGETATION

VEGETATION 2 3 4 5 6 7 8 9 REFER

Flint 0 z 2 W F1 10 11 12 13 14 15 161 1

COMMENTS

DAM z

NAME ADDITIONAL aa v UJ w w

ACTION

NEEDED 9162009 O z0

CHECK

DATE

observed

INSPECTION

caveins

plant

per

inspection

OBSERVATIONS

inspection

Engineering

after after

after

WRS 2

Civil

shortly recommended

OK OK OK OK OK

shortly

AEP

2 controlled

cleared

readings

copy

repaired

excess

EMBANKMENT observed observed observed

observed observed

INSPECTED

but

NA NA NA NA Quarterly Forward

None None None Burrows None None Fair Fair

Vegetation

Pond

WELLS

Ash

APPLICABLE

RECORDER

FLOW

BURROW

READINGS

SCARP

AND

Bottom RECORDS

CONTROL

CONTACT

ITEM

MOVEMENT

ANIMAL MONUMENTS

GAUGE

SLOUGH

Primary IN

AREAS

REFER

SURVEY DRAINS FREQUENCY LOCATION

SEEPAGE SLIDE EMBABUT CAVE EROSION UNUSUAL VEGETATION PIEZOMETERSOBSERV STAFF WEIRS

WET

Flint

17 19 28 31 32 33 34 35

20 21 22 23 24 25 26 Z 27

COMMENTS DAM p w Z

z z Applicable 0 H z F29 t30 z a Cn

Not

ADDITIONAL NA

NAME w aa UJI v a• W >

EEDED

ACTION N 9162009 0 Z 0

CHECK

DATE

plant

INSPECTION

per

plant

per inspection

plant

per

after

inspection

OBSERVATIONS shortly

inspection

after

WRS

1 cleared

after

shortly

OK OK

debris

1 shortly

and

cleared

SPILLWAYS

cleared

observed observed

INSPECTED

NA NA

None None Debris NA NA NA NA NA NA

Vegetation Vegetation

Pond

Ash

APPLICABLE

SCARP

Bottom

CONDITION

AREA

CONDITION

FLOOR MOVEMENT ITEM

BASIN

CONTROL

STRUCTURE

SLOUGH

Primary

REFER

DEBRIS SIDEWALLS CHANNEL UNUSUAL DISCHARGE STILLING INTAKE

SLIDE EROSION VEGETATION APPROACH WEIR TRASHRACK

Flint z 2 w

51 52 53 54 55 57 58 59 60 61 62 63 64 66 67 68 56 65 69

Z COMMENTS

DAM W z J w Z = w Z Z QU a Applicable

OF a

Qa W

J Ow W J m Ow 0 Z Not

ADDITIONAL NA

NAME ° z

>z F F 111

ACTION NEEDED 9162009 p O

CHECK V V V VO

DATE

INSPECTION

plant plant

per per

OBSERVATIONS

inspection inspection

inspected

not WRS 1

after after

WORKS

OK OK OK

1 design

shortly shortly

cleared cleared

observed observed observed

INSPECTED

OUTLET

Debris Debris NA NA NA NA Submerged NA None None None

Pond

Ash TOE

APPLICABLE

DAM

Bottom

CLOSURE

CONDITION

MECHANISM

MOVEMENT ITEM

ALONG

BASIN CLOSURE

PIPE TOWER

STRUCTURE

Primary

REFER

INTAKE EROSION SEEPAGE UNUSUAL

TRASHRACK STILLING PRIMARY SECONDARY CONTROL OUTLET OUTLET

Flint Z w

70 71 72 73 74 75 76 77 78 79 80 81 82 I• 83

COMMENTS DAM W W z Y w O H 0 Applicable

OF a

Not

ADDITIONAL NA

NAME z

ACTION

NEEDED 9162009 O VO CHECK O V V V V V YO VO VO 1 1

after of I controlled

cleared

shortly control

excess

observed observed observed observed observed observed

EMBANKMENT

but

INSPECTED

None None None OK Repaired Good None None None Fair

SURFACE CAVE LOW HORIZONTAL RUTS SLIDE SLOPE SINKHOLE EMBABUT EROSION VEGETATION

VEGETATION 1 1 REFER 1 2 3 4 5 6 7 8 9

Flint

z 11 12 13 14 15 16 w I•

COMMENTS

DAM w z i U 2 a W a10 w

NAME ADDITIONAL NI`ddd2• 0 CCD N J1VOI1S3ANI

U a z C Q a T E N E 0 0 U V0 O 0 n d 0 0 0 0 0 0 C u 0 70 N Q a O Q C 0 0 70 O 0 0 a 0 a a a 70 0 Z Z Z 0 0 a a 0 a 1 x Z 0 U U O U 9 N a E 0 T 0 S U 0 0 0 0 0 0 0 ro a a a a 0 a 0 a C C C Q C C 0 0 0 0 a 0 0 0 0 a Q Z Z Z > Z Z U Z > Z Z 0 0 D c 0 D U U n CD ¢ 0 0 U Q U n E 0 0 CD d 0 U z z 0 0 w CD U m 0 z m z 0 z z ¢ w 0 0 ¢ z > U

U1 0 U 0 z O of 0 0 0 0 ¢ 0 ¢ z 0 z 4 0 a U a z C 0 CD O ¢ ¢ ¢ U >LU W U U 0 > ¢ x > 0 D D U U ¢ 0 z n O 0 U U U LU co U

11 co 0 Co N Co U CO 0 C N m LC ON W31 N N N N N N N 0 MM CO Co Co

GLL3 dSNI 0 DdO1S WV•181SNMO® NOIIVINJWfl ±LSNI LU z Qa • W >

NA NA NA NA NA NA NA NA NA

SLIDE EROSION DEBRIS SIDEWALLS CHANNEL UNUSUAL APPROACH WEIR DISCHARGE TRASHRACK STILLING

VEGETATION

Flint

59 65 66 67 68 I51 69

52 53 54 55 57 58 60 61 62 63 Z w 56

Q Z COMMENTS

DAM Z W O0z W Z =

Applicable W ZZ Q 0 Q U a64 J

W Q J CO Ow W J M Z p 0 Ow 0 w Not

NAME ADDITIONAL M a D w N > z

observed observed observed

INSPECTED

OUTLET

Debris OK NA NA NA NA NA NA None None None

INTAKE PRIMARY SECONDARY CONTROL OUTLET OUTLET EROSION SEEPAGE UNUSUAL

TRASHRACK STILLING

Flint E F2

70 71 72 73 74 75 76 77 79 80 81 82 Z 83

COMMENTS DAM w w U Fa co

NAME ADDITIONAL NA oc w

SLIDE SLOPE SINKHOLE EMBABUT EROSION VEGETATION

SURFACE CAVE LOW HORIZONTAL RUTS VEGETATION 1 2 3 4 5 6 7 8 9 REFER

Flint 10 11 12 13 14 15 z 16

CAVE EROSION UNUSUAL PIEZOMETERSOBSERV STAFF WEIRS SURVEY DRAINS FREQUENCY

WET SEEPAGE SLIDE EMBABUT VEGETATION

Flint

18 31 32 33 34 35

17 19 20 21 22 23 24 25 28 29 30 26 z wI 27

COMMENTS DAM w Iww W W Z 0 Z O laZ

ACTION NEEDED O CHECK O

SIDEWALLS CHANNEL UNUSUAL WEIR DISCHARGE TRASHRACK STILLING

SLIDE EROSION VEGETATION DEBRIS APPROACH

Flint

66 67 68 65 69

55 57 58 59 60 61 62 64 z I• 56

w 51 52 53 54

Q Z Z COMMENTS DAM U Q Z a Z Z Q 63 0 w w IL z W W Z < v Z w J m Z Z

MECHANISM MOVEMENT ITEM

SECONDARY CONTROL OUTLET OUTLET EROSION SEEPAGE UNUSUAL

INTAKE TRASHRACK STILLING PRIMARY

Flint

81 82 83

72 73 74 75 76 77 78 79 80 Z 70 71

COMMENTS DAM 0 w 0 a z O w 0

ALIGNMENT CONDITION CONDITION

RUTS SLIDE SLOPE SINKHOLE EMBABUT EROSION VEGETATION

SURFACE CAVE LOW HORIZONTAL VEGETATION REFER 1 2 3 4 5 6 7 8 9

Flint

10 11 12 13 14 15 Z w 16

DISCHARGE INTAKE STILLING

DEBRIS SIDEWALLS CHANNEL UNUSUAL APPROACH WEIR TRASHRACK

SLIDE EROSION VEGETATION

Flint

58 59 62 63 65 66 67 68 69

56 Z W I2 51 52 53 54 55 57 60 61

Z z COMMENTS

DAM 0 W U az W Z Z < V Q U 64 zz < v J Z O Z OF w Q W Jm O IX J m 0 w £ W C1

MECHANISM MOVEMENT ITEM

STILLING SECONDARY CONTROL OUTLET OUTLET EROSION SEEPAGE UNUSUAL INTAKE TRASHRACK PRIMARY 1

Flint

80 81 83 Z E 82

70 71 72 73 74 75 76 77 79

COMMENTS DAM 0 W U az w O W 0

I scc•as as o o sc<>•o•a k 6 Fcx3s2

S s•ocv ce To>so•• naca s+owa as

SECONDARY ASH •ETTLINC ASIN SURFACE EL 11420 PSH ~rynS•u ltaUTM• STQUCTJ 2ES RfG SOUTWESTERN ELECTRIC POWER COMPANY •P fL+19X111 ice DEPAkTMENI a FLINT CREEK POWER PLANT L u ASH BERM AND CONNECTING CANAL PLAN

9FNNBf M5 BATE 75 FCx 3 B 14 CkE = 1000 I 3 i q T1 Sc2l SEj

F•• n o cgorc •e

SECTION H H K K 5C 1A•H PD BIKE

1 c r SnP•c sT p3c P 2A V LJ0 O cgprn C 0 3i u55• A5 55 Sc 34251 u Goo 0•+0 TOO CPNpE 3 00 n5 Szc 515 5 N C A os5 501 rpm E+cnv0TSti s E55CLM1 w 660500 0044•c 52lFv45 4 005 c s 53010000 pc AS O0n oc 3AS0 CO l51 015 I a 6005 c 5 c 50 Pll004 vn

C0500AC00 To 000 S Fu0NS 36 f_ 1•2

AS1 i ACCUAC nv a N s O0 Eccv0c05 M ATE 0nl Y SWEPO wu• o I 6 ICSO P•O 2 Ac yvic vw+yo 0r 5 DETAIL 2 TYPICAL DIAPHRAM

SECTION DDL NTS

POND DIKE

EPCOASH CROSS 5ECZ1O11S L 4 p cra a 3• vw4aW FLINT CREEK POWER RA7

SOUTHWESTERN ELECTRIC POWER CO NISECTION LL •C CoNcM CT ON prnn L00

DETAIL I

FCX 3 SCALE NoNc SH2 I

wov o c•gwe••

• Tao •F FlaTnrARc

SECTION FE PRIMARY CONTROL CANAL AND SPILLWAY

•BtEi

T• eea w••< < II<60

r •a9••6L•

•c w n nwo • ics cc cui E •I313 • •• an>• c0•vva

SECTION FF

VVfPS Eaq ct 1r42V

44 al cis llwp cur o c o E 11coc 111

111SECTIONGG

5 B 31

ASH POND SPILLWAY SECTIONS

FLINT CREEK POWER PLANT

SOUTHWESTERN ELECTRIC POWER CO

C O consTa•c ErRTU1

I ou gi0l5 N SCALE I FCXSH 3 w Eto

g Q •sn pil ca•s =su rx a s NI su•ce v

PLAN OF WEIR BOX STRUCTURE U NT

DETAIL 2 SCA=E1=1V•=bv

NH+nowSro

n u r S a so DETAIL I

t DcL1 5CAE I= I J

EV DATE BY SUBJECT SOUTHWESTERN ELECTRIC POWER CO ==DEPARTMENT A s Y=n w FLINT CREEK POWER PLANT

ASH STORAGE BASIN CONTROL STRUCTURES

CAD BI

JRWN BY 4ARTIN DATE 5` 61E DRAB V•` I OZFIley Rm

EL E VAT 107 SECTION

STOP LOG DETAIL 5 REOD

SECTION RR

SECTION TT

SECTION S S f LSJ •nTn• EcB aEoca Or f•uawn Ger•lip

TIUTTO E4 1 O

4 440540 uune Sm6 •9ny rm

Erro OEynsoTce r

KBsa 1 x•a4 w ax

OECTION PP

NOTE Al Sicls w O a 5r•v cn RaaT SECTION KK Bi a Rc• CO3O•C• •HnY `1 s 1CLL PRpnGGW Rvw• O Eay s Te rra uHC VCS5Ss SEN Sic • 2 •2 Pp kOa Te P r

SECTION ZZ

t0f1fl G FAST4100 4451546740107015U5 4 WASHEei ID Cor 10 eE 34 1 oioOoRrnn 19 Wrwv1t7 ALL LAIn1G 4101414 601TSEUI +ASCLSS

KTJ 1 J SECTION U U

SECTION JJ Rt DOTE BY SUBJECT 5445 uo• •••

P CR x04074 7051 bnl 6 9811 HF ALCEO 407 51wnu7 74 07 74 41 0

C I 0IA I 0° o nw7070 np

DETAIL +9 TYF

NOTE SOUTHWESTERN ELECTRIC POWER CO AE CHA111E1S LI SNIBS WASIY+G1 sc Pa Caalu0oDEPART0ENT G SE C1VA1ILE_ FLINT CREEK POWER PLANT

ASH STORAG SRSIS CONTROL STQO ORES 4 50041007 ASH BASIN SOBUAL OUTLET SECTION HH DETAIL A FCX3SHI FCxns TRACED C

D7i WN E WRLR DATE 41I SCALE n NDRSxo FC•Z9Nz

APPENDIX IV

Guidelines for Herbicide Use on Earthen Dams RECOMMENDATIONS ON HERBICIDE USE TO CONTROL VEGETATION ON EARTHEN DAMS

HERBICIDE APPLICATION RECOMMENDATIONS

Wind direction and speed should be monitored during application of the herbicides to minimize drift into areas of Drift of herbicides into also on the rate of the concern nontarget areas is dependent evaporation

the the hottest the pesticide therefore avoid application of herbicides during part of day when evaporation is

that the size consistent with of the herbicide be highest It is recommended largest droplet adequate coverage

drift well The of used to further reduce drift Higher spray volumes typically reduce as application herbicides the earthen dams should be rainfall within 24 hours to further reduce the

on delayed if is expected

loaded into the runoff of herbicides into the adjacent water bodies The herbicides should be mixed and spray units far from the dam locations that wont enter the enough away to ensure potential spills aquatic systems

When feasible utilize individual plant treatments The treatment of individual plants would reduce the

the which could result in lower costs associated volume of herbicide required in control of dam vegetation and with the vegetation management plan In addition adverse impacts to beneficial nontarget plant species aquatic species would be minimized due to the avoidance of exposure and the lower potential for drift and runoff Once an earthen data has been treated with herbicide establish a maintenance plan to reduce the potential for future large scale herbicide applications The establishment of a mowing and trimming schedule

wildflowers the earthen darns The could be beneficial to the establishment of native grasses forbs and on invasion of and reduce the promotion of grasses through these methods Would reduce the woody vegetation

for additional the the need herbicide applications Should use of herbicides be required in future applications should be made during the early successional stages so that individual plant treatments would be economically and logistically feasible

THREATENED AND ENDANGERED SPECIES CONCERNS

of herbicides with According to the Federal Insecticide Fungicide and Rodenticicle Act the use must comply the Endangered Species Act Although the measures proposed herein should minimize adverse impacts to fish and wildlife special should be taken to ensure that adverse

resources in general precautions impacts to rare threatened and endangered species are avoided

BRUSH CONTROL HERBICIDES FOR USE ON DAMS EXCEPT AS NOTED

list to effective the control of The following of herbicides contains chemicals and formulations known be in vegetation typically found growing on open and previously disturbed habitats similar to the vegetation associations expected to be growing on dams These herbicides are also known to have low toxicity to terrestrial and aquatic organisms and are not known to leach into ground and surface waters The

the the of the herbicides a implementation of recommendations herein during application following in manner consistent with the herbicides label should minimize adverse impacts to fish and wildlife resources

and around the dam The list of herbicides certainly not allinclusive as new herbicides are on following is consistently being introduced

24D American Brand 24D DMA 4 IVM Weedar 64

introduced 1946 and the most used 24D 24Dichlorophenoxyacetic acid was in is widely herbicide the world different manufacturers 24D and the list of formulations in Many produce

are to a selective that to control above included only provide examples 24D is herbicide is used

broadleaf herbaceous plants The salt formulations of 24D are relatively nontoxic to fish and

wildlife species However the ester formulations of 24D are toxic to fish Therefore avoid the use

Page 1 of 4

HlnternalDam Dike InspectionsTrequently Used AttachmentsVegetation controldoc formulations of the ester formulations of 24D in the control of vegetation on dates The 24D salt

are used to control box elder Ater nugmtdo willow Salix spp thistle wild rose Cirsium spp morning glory 1pomoea spp poison ivy Toxicodendron radicans cocklebur Rosa spp Virginia creeper Parthenocissus quinquefolia ragweed Ambrosia spp 1nthirn spp Russian thistle Salsola kali and sunflower Helianbus spp

Glyphosate Accord Aquamaster Glypro Pondmaster Rodeo

a herbicide used to control broadleaf Glyphosate is broadspectrum nonselective systemic grasses

and Because a herbicide care should be taken weeds woody plants glyphosate is broadspectrum for during applications to minimize adverse impacts to grasses and native vegetation important

control stabilization earthen dams used to control erosion and of Glyphosate is dogwood Corpus reed spp maple Ater spp oak Quercus spp giant Arundo Ionax

salt cedar Tamarix spp sweet gum Liquidambar siyraciflrra sycamore Pantanus occidentalis willow cocklebur sunflower Heianthus spp alligatorweed Alternanthera philoxeroides cattail black Tjpia spp blackberry Rubus spp kudzu Pueraria lobata honeysuckle Lonicera spp locust Robinia pseudoacacia persimmon Diospyros spp wild rose Russian olive Elaeagnus angustifolia Chinese tallow Sapimn sebiferpm wax

myrtle Morela cerifera and sumac Rims spp

Imazapyr Arsenal Chopper Habitat Stalker

a nonselective herbicide used to control annual and perennial hnazapyr is broadspectrum systemic and and Because grasses broadleaf herbaceous plants woody plants riparian aquatic plants

a care should be taken imazapyr is broadspectrum herbicide during applications erosion control and to minimize adverse impacts to grasses and native vegetation important for

stabilization used to control giant thistle cocklebur of earthen dams Imazapyr is reed ragweed wild saltbush Atriplex spp greenbriar Smilax spp honeysuckle morning glory poison ivy rose wild ash kudzu trumpet creeper Campsis radicans grape Vitis spp Fraxinus spp maple black locust box elder chinaberry Melia azedarach Chinese tallow cottonwood Popuhts deltoides dogwood elm Ulmus spp hawthorn Crataegus spp mulberry

Mores spp oak persimmon Diospyros spp pine Pinus spp privet Ligustrum japonicunr Russian olive saltcedar sumac sweetgum treeofheaven Ailanthus

altissima Vaccinimn spp waxmyrtle willow and yaupon Ilex vomitoria

Fosamine Ammonium Krenite

to control brush railroad Fosamine ammonium is used along highway rightsofway rightsofway

industrial used to control sites storage areas and utility and pipeline rightsofway It is woody such Chinese wild wild species as oak pine sumac sweetgum tallow elm grape rose sycamore

and treeofheaven also used combination with metasulfuron to control It is in methyl Escort XP Fosamine ammonium eastern red cedar Juniperus virginiana treeofheaven ash elm and maple

also used with to control American Calicmpa americana

is imazapyr Arsenal beautyberry baccharis Baccharis neglecta Vaccinimu spp waxmyrtle box elder black locust dogwood elm maple sassafras Sassafras sassafras and willow

Metsulfuron Methyl Escort XP

Escort XP a selective and herbicide used to control broadleaf herbaceous and is pre postemergence

has been used to control thistle sunflower woody species It cocklebur blackberry Rubus spp red honeysuckle wild rose ash black locust cottonwood eastern cedar elm

hackberry Celtis spp hawthorn mulberry wild grape oak Osage orange Maclura pomifera maple sweetgum treeofheaven Vaccinium spp and willow

Page 2 of 4

HlnternalDam Dike InspectionsTrequently Used AttachmentsVeaetation controldoc Diquat Reward

a nonselective contact herbicide used to control aquatic and terrestrial vegetation Diquat is

toxic to for use because

is it quickly Although diquat is aquatic invertebrates it acceptable aquatic

to soil and sediments the water care should be taken while applying binds suspended in However

that direct with bodies avoided In can be toxic to diquat so contact water is addition diquat many

that be beneficial the control of dam erosion grass species and other vegetation may in Diquat beneficial should be applied to minimize impacts to desired vegetation

BRUSH CONTROL HERBICIDES TO AVOID ON DAMS

to effective the control of and formulations known be in The following list of herbicides contains chemicals

habitats similar to those found on earthen dams However because they are known to upland vegetation in

the soil and accumulate and surface waters or are known to be toxic to aquatic leach through in ground

their avoided the control of dam organisms use should be in vegetation

Clopyralid Reclaim Stinger and Transline

exhibits to terrestrial and mobile in

is Although clopyralid a low toxicity aquatic organisms it highly used for and the soils and can contaminate surface and ground water which may be irrigation

the of dates to recommended that the use of

is drinking purposes Because of proximity water it

the control of dams clopyralid be avoided in vegetation on

and Curtail Clopyralid with 24D or MCPAEHE Curtail M

Curtail and Curtail M are herbicide formulations which use clopyralid as an active ingredient with Curtail contains clopyralid with 24D while Curtail M contains clopyralid MCPAEHE

contain recommended that the use of Curtail and Curtail Because both formulations clopyralid it is

M be avoided in the control of vegetation on dams

Glyphosate

nontoxic to certain surfactants added to some Although glyphosate is practically aquatic organisms toxic to terrestrial formulations of glyphosate have been shown to be highly aquatic species and amphibians Nonaquatic formulations of glyphosate Accord SP Accord XRT Glyphomax

the control

should be avoided in of on Glypro Plus Honcho Roundup Touchdown vegetation dams In addition other formulations containing glyphosate combined with 24D or dicamba Campaign Fallowniaster Landmaster II should be avoided unless labeled for aquatic use

Picloram Tordon 22K Tordon K

terrestrial mobile in

and it is Although picloram exhibits a low toxicity to aquatic organisms highly the soils and can contaminate surface and ground water which may be used for irrigation and

the to recommended that the use of

is drinking purposes Because of proximity of dams water it

avoided the control of on dams picloram be in vegetation

Picloram with 24D Grazon P+D Pathway Tordon RTU Tordon 101

the soil and known to leach into surface and mobile profile is Because picloram is extremely in recommended that the use of Grazon P+D Tordon RTU and Tordon ground water it is Pathway

the control of dams 101 be avoided in vegetation on

Page 3 of 4

HlnternalDam Dike lnspections requenth Used AttachmentsVcgetation controldoc though triclopyr exhibits a low toxicity to terrestrial and aquatic

a soils and can contaminate surface and round water which rna

of the of darns to i inking purposes Because proximity water it

clonyr be avoided the control of vegetation on dams

is toxic r cut

Avoid tht

vranct are mobile soil profile

ecaus in the

at into ind mended that the use of Redeem RP be avoided in 1 control Permit number AR0037842

AUTHORIZATION TO DISCHARGE WASTEWATER UNDER THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM AND THE ARKANSAS WATER AND AIR POLLUTION CONTROL ACT

accordance with provisions Arkansas Water and Air Pollution Control Act Act 472

In the of the 1949 amended Ark Code Ann 84101 seq and the Clean Water Act USC 1251

of as et 33 seq

American Electric Power

Southwestern Electric Power Company SWEPCO Flint Creek Power Plant 21797 SWEPCO Plant Road Gentry AR 72734

authorized discharge from a facility located approximately 3 miles southwest Gentry

is to at of Sections 4 5 8 and Township North Range West Benton County Arkansas

in 18 18 33 in

Latitude 36 15’ 22” Longitude 94 31’ 29”

receiving waters named

SWEPCO Reservoir thence Little Flint Creek thence Flint Creek Segment

to to in 3J of the Arkansas River Basin

The outfalls located following coordinates

are at the

Outfall 001 Latitude 36 14’ 00” Longitude 94 33’ 02”

Outfall 101 Latitude 36 15’ 03” Longitude 94 35”

31’ Outfall 401 Latitude 36 15’ 27” Longitude 94 31’ 32”

Discharge shall accordance with effluent limitations monitoring requirements and other

be in conditions forth Parts I and hereof

set in II III IV

The response comments attached this final permit

to is to

This permit shall become effective March 1 2006

This permit and authorization discharge shall expire midnight February 2011

the to at 28

Signed this 31st day January 2006

Martin Maner PE Chief Water Division

Arkansas Department Environmental Quality

E NPDES PermitAR0037842 Permit number AR0037842

Page 1 Part

of IA

PART I PERMIT REQUIREMENTS

SECTION A EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS OUTFALL 001 –SWEPCO

Reservoir discharge

During period beginning effective date and lasting until date expiration the permittee authorized discharge from

the on of is to outfall serial number 001 Such discharges shall limited and monitored permittee specified below

be by the as

Effluent Characteristics Discharge Limitations Monitoring Requirements

Mass Concentration lbsday unless mgl unless Frequency Sample Type

otherwise specified otherwise specified

Monthly Daily Monthly Daily Avg Max Avg Max Flow1 NA N A Report Report Continuous Record Minimum Maximum NA N A Once week pH su 9.0 su Grab

6.0

1 Report monthly average and daily maximum MGD There shall maintained a daily average flow least 2 1.29 MGD

at as be of cfs

flow through spillway overflow seepage pumping into Little Flint Creek

There shall discharge distinctly visible solids scum foam a persistent nature nor shall there any formation slime bottom

be no of or of be of deposits sludge banks visible sheen Sheen means iridescent appearance surface water

or No an on the of the

Samples taken compliance with monitoring requirements specified above shall taken Outfall 001 weir

in the be at the at the located property line Little Flint Creek

at the in

ENPDES PermitAR0037842 Permit number AR0037842

Page 2 Part

of IA

PART I PERMIT REQUIREMENTS

SECTION A EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS OUTFALL 101 –combined wastewater bottom ash discharge low volume wastewater and storm water runoff including coal pile runoff and treated municipal wastewater from City Gentry

the of

During period beginning effective date and lasting until date expiration the permittee authorized discharge from

the on of is to outfall serial number 101 Such discharges shall limited and monitored permittee specified below

be by the as

Effluent Characteristics Discharge Limitations Monitoring Requirements

Mass Concentration lbsday unless mgl unless Frequency Sample Type

otherwise specified otherwise specified

Monthly Daily Monthly Daily Avg Max Avg Max

Flow1 NA N A Report Report Continuous Record Total Suspended Solids TSS NA NA Once week Grab

25 43 Oil and Grease O G NA NA 6 8 Once 2 months Grab Minimum Maximum NA N A Once week Grab pH su 9.0 su

6.0 Chronic Biomonitoring2 NA NA NA NA once quarter 24 composite

hr 2 Pimephales promelas Chronic 7 Day Average

PassFail Lethality 7day NOEC TLP6C Report Pass 0Fail1 once quarter 24 composite

hr PassFail Growth 7day NOEC TGP6C Report Pass 0Fail1 once quarter 24 composite

hr Survival 7day NOEC TOP6C Report once quarter 24 composite

hr Coefficient Variation TQP6C Report once quarter 24 composite

of hr Growth 7day NOEC TPP6C Report once quarter 24 composite

2 Ceriodaphnia dubia Chronic 7 Day Average PassFail Lethality 7day NOEC TLP3B Report Pass 0Fail1 once quarter 24 composite

hr PassFail Production 7day NOECTGP3B Report Pass 0Fail1 once quarter 24 composite

hr Survival 7day NOEC TOP3B Report once quarter 24 composite

hr Coefficient Variation TQP3B Report once quarter 24 composite

of hr Reproduction 7day NOEC TPP3B Report once quarter 24 composite

See Condition No 5 Part

of III The City Gentry discharges treated municipal effluent subject limitations NPDES Permit No AR0020184 into Flint

of to the of its

Creek Power Plant’s primary ash pond Flint Creek Power Plant bears responsibility quality City Gentry’s

no for the of the of effluent any treatment that effluent

or for of

1 Report monthly average and daily maximum MGD

as 2 See Condition No 4 Part Biomonitoring Requirements

of III

There shall discharge distinctly visible solids scum foam a persistent nature shall there any formation slime bottom

be no of or of nor be of deposits sludge banks visible sheen Sheen means iridescent appearance surface water

or No an on the of the

Samples taken compliance with the monitoring requirements specified above shall taken discharge from

in be at the the secondary ash pond final treatment unit

ENPDES PermitAR0037842 Permit number AR0037842

Page 3 Part

of IA

PART I PERMIT REQUIREMENTS

SECTION A EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS OUTFALL 401 –once through cooling water

During period beginning effective date and lasting until date expiration the permittee authorized discharge from

the on of is to outfall serial number 401 Such discharges shall limited and monitored permittee specified below

be by the as

Effluent Characteristics Discharge Limitations Monitoring Requirements

Mass Concentration lbsday unless mgl unless Frequency Sample Type

otherwise specified otherwise specified

Monthly Daily Monthly Daily Avg Max Avg Max Flow NA N A 450 MGD 450 MGD Continuous Record 1 Total Residual ChlorineTRC NA 62.6 NA mg Onceweek Grab3

0.2 l2 Temperature4 NA NA NA 129.2 F Continuous Record Minimum Maximum NA N A Onceweek Grab pH su 9.0 su

6.0 Chronic Biomonitoring5 NA NA NA NA once quarter 24 composite

hr 5 Pimephales promelas Chronic 7 Day Average

PassFail Lethality 7day NOEC TLP6C Report Pass 0Fail1 once quarter 24 composite

hr PassFail Growth 7day NOEC TGP6C Report Pass 0Fail1 once quarter 24 composite

hr Survival 7day NOEC TOP6C Report once quarter 24 composite

hr Coefficient Variation TQP6C Report once quarter 24 composite

of hr Growth 7day NOEC TPP6C Report once quarter 24 composite

5 Ceriodaphnia dubia Chronic 7 Day Average

PassFail Lethality 7day NOEC TLP3B Report Pass 0Fail1 once quarter 24 composite

hr PassFail Production 7day NOECTGP3B Report Pass 0Fail1 once quarter 24 composite

hr Survival 7day NOEC TOP3B Report once quarter 24 composite

hr Coefficient Variation TQP3B Report once quarter 24 composite

of hr Reproduction 7day NOEC TPP3B Report once quarter 24 composite

Flow measurements may calculated using pump records

1 See Condition No 7 Part Total Residual Chlorine shall not discharged from any single generating unit more than 2

of III be for hours per day

2 Instantaneous Maximum

3 Sample must representative periods chlorination

be of of 4 Temperature may measured condenser discharge Daily maximum temperature shall highest daily flow weighted

be at the be the temperature calculated month

for the 5 See Condition No 4 Part Biomonitoring Requirements

of III

There shall discharge distinctly visible solids scum foam a persistent nature nor shall there any formation slime bottom

be no of or of be of deposits sludge banks visible sheen Sheen means iridescent appearance surface water

or No an on the of the

Samples taken compliance with monitoring requirements specified above shall taken Outfall 401 prior discharge

in the be at to SWEPCO Reservoir

ENPDES PermitAR0037842 Permit number AR0037842

Page 1 Part

of IB

SECTION B SCHEDULE OF COMPLIANCE

The permittee shall achieve compliance with effluent limitations specified discharges

the for in accordance with following schedule

the

Compliance required effective date permit

is on the of the

The permittee shall comply with Cooling Water Intake regulations found Title Code

the in 40 of Federal Regulations Part 125 Subpart J These regulations include limited

not are but to the following provisions

a The permittee shall submit two copies Proposal Information Collection

of the for to the NPDES Branch Water Division prior start information collection

of the to the of activities and

b The permittee shall submit two copies completed Comprehensive Demonstration

of the Study the NPDES Branch Water Division prior January 7 2008

to of the to or on or

before federal deadline that the EPA may reestablish complying with the

the for requirements CFR 125 Subpart J The permittee shall meet other applicable

of 40 all requirements this regulation

E NPDES PermitAR0037842 Permit Number AR0037842

Page 1 Part

of II

PART

II STANDARD CONDITIONS

SECTION A –GENERAL CONDITIONS

1 Duty Comply

The permittee must comply with conditions this permit Any permit noncompliance

all of constitutes a violation federal Clean Water Act and Arkansas Water and Air Pollution

of the the Control Act and grounds enforcement action permit termination revocation and

is for for reissuance modification denial a permit renewal application Any values reported

or or for of in the required Discharge Monitoring Report which are excess effluent limitation

in of an specified Part I shall constitute evidence violation such effluent limitation and this

in of of of permit

2 Penalties Violations Permit Conditions

for of

The Arkansas Water and Air Pollution Control Act provides that any person who violates any provisions a permit issued under Act shall guilty a misdemeanor and upon conviction

of the be of thereof shall subject imprisonment more than one 1 year a fine more than

be to for not or of not

thousand dollars 10,000 both such fine and imprisonment each day such

ten or by for of violation Any person who violates any provision a permit issued under Act may also

of the be subject civil penalty such amount court shall find appropriate exceed ten

to in as the not to thousand dollars 10,000 each day such violation The fact that any such violation may

for of constitute a misdemeanor shall not a bar maintenance such civil action

be to the of

3 Permit Actions

This permit may modified revoked and reissued terminated cause including

not be or for but limited following

to the

a Violation any terms conditions this permit

of or of or b Obtaining this permit misrepresentation failure disclose fully relevant facts

by or to all or c A change any conditions that requires either a temporary permanent reduction

in or or elimination authorized discharge

of the or d A determination that permitted activity endangers human health environment and

the or the

can only regulated acceptable levels permit modification termination

be to by or e Failure the permittee comply with provisions APCEC Regulation No 9 Permit

of to the of fees required condition A herein

as by II 10

The filing a request permittee a permit modification revocation and reissuance

of by the for or termination a notification planned changes anticipated noncompliance does stay any

or of or not permit condition

E NPDES PermitAR0037842 Permit Number AR0037842

Page 2 Part

of II

4 Toxic Pollutants

Notwithstanding Part A3 any toxic effluent standard prohibition including any schedule

II if or compliance specified such effluent standard prohibition promulgated under Regulation

of in or is No 2 amended regulation establishing water quality standards surface waters State

as for of the Arkansas Section 307a Clean Water Act a toxic pollutant which present

of or of the for is in the discharge and that standard prohibition more stringent than any limitations pollutant

or is on the in this permit this permit shall modified revoked and reissued conform toxic effluent

be or to to the standards prohibition and permittee notified

or the so

The permittee shall comply with effluent standards narrative criteria prohibitions established

or under Regulation No 2 Arkansas Water Quality Standards amended Section 307 a

as or of the Clean Water Act toxic pollutants within time provided regulations that establish those

for the in the standards prohibitions even permit has been modified incorporate

or if the not yet to the requirement

5 Civil and CriminalLiability

Except provided permit conditions “Bypassing” Part B4 and “ Upsets” Part

as in on II a B5b nothing this permit shall construed relieve permittee from civil criminal

II in be to the or penalties noncompliance Any false materially misleading representation concealment

for or or of information required reported provisions this permit applicable state and federal

to be by the of or statues regulations which defeats the regulatory purposes the permit may subject the

or of permittee criminal enforcement pursuant Arkansas Water and Pollution Control Act

to to the Air Act 472 1949 amended

of as

6 Oil and Hazardous Substance Liability

Nothing this permit shall construed preclude institution any legal action relieve

in be to the of or

permittee from any responsibilities liabilities penalties which permittee may

the or to the is or be subject under Section 311 Clean Water Act

of the

7 State Laws

Nothing this permit shall construed preclude institution any legal action relieve

in be to the of or permittee from any responsibilities liabilities penalties established pursuant any

the or to applicable State law regulation under authority preserved Section 510 the Clean Water

or by of Act

ENPDES PermitAR0037842 Permit Number AR0037842

Page 3 Part

of II

8 Property Rights

The issuance this permit does not convey any property rights any sort any exclusive

of of or privileges nor does authorize any exclusive privileges nor does authorize any injury private

it it to property any invasion personal rights any infringement Federal State local laws

or of nor of or or regulations

9 Severability

The provisions this permit severable and any provision this permit application

of are if of or the

any provisions this permit any circumstance held invalid application such

of of to is the of provision other circumstances and remainder this permit shall not affected thereby

to the of be

Permit Fees

The permittee shall comply with applicable permit requirements wastewater discharge

all fee for permits described APCEC Regulation No 9 Regulation Fee System

as in for the for Environmental Permits Failure promptly remit required fees shall grounds the

to all be for

Director initiate action terminate this permit under provisions CFR 122.64 and

to to the of 40 124.5 d adopted APCEC Regulation No 6 and provisions APCEC Regulation No 8

as in the of

SECTION B –OPERATION AND MAINTENANCE OF POLLUTION CONTROLS

1 Proper Operation and Maintenance

a The permittee shall times properly operate and maintain facilities and systems

at all all of treatment and control and related appurtenances which are installed used the

or by permittee achieve compliance with conditions this permit Proper operation and

to the of maintenance also includes adequate laboratory controls and appropriate quality assurance

procedures This provision requires operation backup auxiliary facilities similar

the of or or systems which installed a permittee only when operation necessary achieve

are by the is to compliance with the conditions permit

of the b The permittee shall provide adequate operating staff which duly qualified carryout

an is to

operation maintenance and testing functions required insure compliance with

to the conditions this permit

2 Need Halt Reduce not a Defense

to or

shall not a defense a permittee enforcement action that would have been necessary

It be for in an it

halt reduce permitted activity order maintain compliance with conditions this

to or the in to the of permit Upon reduction loss failure treatment facility permittee shall extent

or of the the to the necessary maintain compliance with permit control production discharges both until the

to its or or facility restored alternative method treatment provided This requirement applies

is or an of is for example when primary source power treatment facility reduced lost

the of for the is is or alternate power supply fails

ENPDES PermitAR0037842 Permit Number AR0037842

Page 4 Part

of II

3 Duty Mitigate

The permittee shall take reasonable steps minimize prevent any discharge violation

all to or in of this permit which a reasonable likelihood adversely affecting human health

has of or the environment water receiving discharge

or the the

4 Bypass Treatment Facilities

a Bypass not exceeding limitation

The permittee may allow any bypass occur which does cause effluent limitations

to not to exceeded only also essential maintenance assure efficient operation

be but if is for to it These bypasses not subject the provisions Part B 4band 4 c

are to of II

b Notice

1 Anticipated bypass permittee knows advance need a bypass shall

If the in of the for it submit prior notice possible least days before date bypass

if at ten the of the 2 Unanticipated bypass The permittee shall submit notice unanticipated bypass

of an as required part D6 24 hour notice

in II

c Prohibition bypass

1 Bypass prohibited and Director may take enforcement action against a permittee

is the bypass unless

for a Bypass was unavoidable prevent loss life personal injury severe property

to of or damage

b There were feasible alternatives bypass such use auxiliary

no to the as the of

treatment facilities retention untreated wastes maintenance during normal

of or

periods equipment downtime This condition satisfied permittee could

of is not if the have installed adequate backup equipment prevent a bypass which occurred

to during normal preventive maintenance and

or c The permittee submitted notices required Part B4b

as by II 2 The Director may approve anticipated bypass after considering adverse effects

an its if Director determines that will meet three conditions listed above Part

the it the in B4c1

5 Upset Conditions

a Effect upset upset constitutes affirmative defense action brought

of an An an to an for noncompliance with such technology based permit effluent limitations requirements

if the Part B5 b this section met No determination made during administrative

of II of are

review claims that noncompliance was caused upset and before action

of by an for

noncompliance final administrative action subject judicial review

is to

ENPDES PermitAR0037842 Permit Number AR0037842

Page 5 Part

of II

b Conditions necessary demonstration upset A permittee who wishes establish

for of to the affirmative defense upset shall demonstrate through properly signed contemporaneous

of operating logs other relevant evidence that

or 1 upset occurred and that permittee can identify specific cause s upset

An the the of the 2 The permitted facility was time being properly operated

at the 3 The permittee submitted notice upset required Part D6 and

of the as by II 4 The permittee complied with any remedial measures required Part B3

by II c Burden proof any enforcement proceeding permittee seeking establish the

of In the to occurrence upset has burden proof

of an the of

6 Removed Substances

Solids sludges filter backwash other pollutants removed the course treatment control

or in of or waste waters shall disposed a manner such prevent any pollutant from such

of be of in as to materials from entering waters State Written approval must obtained from ADEQ

the of the be the land application only

for

7 Power Failure

The permittee responsible maintaining adequate safeguards prevent discharge

is for to the of untreated inadequately treated wastes during electrical power failure either means

or by of alternate power sources standby generators retention inadequately treated effluent

or of

SECTION C MONITORING AND RECORDS

1 Representative Sampling

Samples and measurements taken required herein shall representative volume and

as be of the nature monitored discharge during entire monitoring period samples shall taken

of the the All be

monitoring points specified this permit and unless otherwise specified before effluent

at the in the joins diluted any other waste stream body water substance Monitoring points shall

or is by of or not changed without notification and approval the Director Intermittent discharges

be to the of shall monitored

2 Flow Measurement

Appropriate flow measurement devices and methods consistent with accepted scientific practices shall selected and used insure accuracy and reliability measurements volume

be to the of of the of monitored discharges The devices shall installed calibrated and maintained insure

be to the accuracy measurements consistent with accepted capability that type device

of the are the of of Devices selected shall capable measuring flows with a maximum deviation less than

be of of 10 from true discharge rates throughout the range expected discharge volumes and shall

of be installed monitoring point discharge

at the of the

3 Monitoring Procedures

ENPDES PermitAR0037842 Permit Number AR0037842

Page 6 Part

of II

Monitoring must conducted according procedures approved under CFR Part 136

be to test 40 unless other test procedures have been specified this permit The permittee shall calibrate and

in perform maintenance procedures monitoring and analytical instrumentation intervals

on all at frequent enough insure accuracy measurements and shall insure that both calibration and

to of maintenance activities will conducted adequate analytical quality control program

be An including analysis sufficient standards spikes and duplicate samples insure accuracy

the of to the required analytical results shall maintained permittee designated commercial

of all be by the or laboratory a minimum spikes and duplicate samples analyzed 10 the samples

At are to be on of

4 Penalties Tampering

for

The Arkansas Water and Air Pollution Control Act provides that any person who falsifies tampers with knowingly renders inaccurate any monitoring device method required maintained

or or to be under Act shall guilty a misdemeanor and upon conviction thereof shall subject

the be of be to imprisonment more than one 1 year a fine more than thousand dollars

for not or of not ten 10,000 both such fine and imprisonment

or by

5 Reporting Monitoring Results

Monitoring results must reported a Discharge Monitoring Report DMR form EPA No

be on 3320 1 Permittees required preprinted DMR forms provided ADEQ unless specific

are to use by written authorization use other reporting forms obtained from ADEQ Monitoring results

to is obtained during the previous calendar month shall summarized and reported a DMR form

be on postmarked later than 25th day month following completed reporting period

no the of the the to begin effective date permit Duplicate copies DMR’s signed and certified

on the of the of as required Part d and other reports required Part D Reporting Requirements shall

by II 11 all by II submitted Director following address

be to the at the

NPDES Enforcement Section

Water Division

Arkansas Department Environmental Quality

of 8001 National Drive PO Box 8913

Little Rock AR 72219 8913

permittee uses outside laboratory facilities sampling and analysis name and address

If for or the of the contract laboratory shall included the DMR

be on

ENPDES PermitAR0037842 Permit Number AR0037842

Page 7 Part

of II

6 Additional Monitoring Permittee

by the

permittee monitors any pollutant more frequently than required this permit using test

If the by procedures approved under CFR 136 specified this permit results this monitoring

40 or as in the of shall included calculation and reporting data submitted DMR Such increased

be in the of the in the frequency shall also indicated DMR

be on the

7 Retention Records

The permittee shall retain records monitoring information including calibration and

of all all maintenance records and original strip chart recordings continuous monitoring

all for instrumentation copies reports required this permit and records data used

of all by of all to complete the application this permit a period least 3 years from the date the sample

at for for of of measurement report application This period may extended request Director any

or be by of the at time

8 Record Contents

Records and monitoring information shall include

a The date exact place time and methods sampling measurements and preservatives

of or used any

if b The individuals s who performed sampling measurements

the or c The date s and time analyses were performed d The individual s who performed analyses

the e The analytical techniques methods used and

f The measurements and results such analyses

9 Inspection and Entry

The permittee shall allow Director authorized representative upon presentation

the or an the of credentials and other documents may required law

as be by to a Enter upon the permittee’s premises where a regulated facility activity located

or is or conducted where records must kept under conditions this permit

or be the of b Have access and copy reasonable times any records that must kept under

to at be the conditions this permit

of c Inspect reasonable times any facilities equipment including monitoring and control

at equipment practices operations regulated required under this permit and

or or d Sample inspect monitor reasonable times purposes assuring permit

or at for the of compliance otherwise authorized Clean Water Act any substances

or as by the or parameters any location

ENPDES PermitAR0037842 Permit Number AR0037842

Page 8 Part

of II

SECTION D –REPORTING REQUIREMENTS

1 Planned Changes

The permittee shall give notice and provide plans and specification Director review and

to the for approval prior any planned physical alterations additions permitted facility Notice

to or to the is required only when

For Industrial Dischargers

a The alteration addition a permitted facility may meet one criteria determining

or to of the for whether a facility a new source CFR Part122.29 b

is in 40 b The alteration addition could significantly change the nature increase the quantity

or or of pollutants discharged This notification applies pollutants which subject neither

to are to effluent limitations permit nor notification requirements under CRF Part 122.42 a1 in the to 40

For POTW Dischargers

Any change facility discharge including introduction any new source significant

in the the of or discharge significant changes quantity quality existing discharges pollutants

or in the or of of must reported permitting authority case any new connections increased flows

be to the In no are significant changes influent quality permitted that cause violation the effluent limitations

or in of specified herein

2 Anticipated Noncompliance

The permittee shall give advance notice Director any planned changes permitted

to the of in the facility activity which may result noncompliance with permit requirements

or in

3 Transfers

The permit nontransferable any person except after notice Director The Director may

is to to the require modification revocation and reissuance permit change name

or of the to the of the permittee and incorporate such other requirements may necessary under Act

as be the

4 Monitoring Reports

Monitoring results shall reported intervals and form specified Part C5

be at the in the in II Reporting Discharge Monitoring Reports must submitted even when discharge

be no occurs during the reporting period

5 Compliance Schedule

Reports compliance noncompliance with any progress reports interim and final

of or or on requirements contained any compliance schedule this permit shall submitted later than

in of be no

ENPDES PermitAR0037842 Permit Number AR0037842

Page 9 Part

of II

days following each schedule date Any reports noncompliance shall include cause

14 of the of noncompliance any remedial actions taken and probability meeting next scheduled

the of the requirement

6 Twenty four Hour Report

a The permittee shall report any noncompliance which may endanger health

or the environment Any information shall provided orally within hours from time the

be 24 the permittee becomes aware circumstances A written submission shall also provided

of the be within 5 days time permittee becomes aware circumstances The written

of the the of the

submission shall contain following information

the 1 a description noncompliance and cause

of the its 2 the period noncompliance including exact dates and times and the noncompliance

of if been corrected anticipated time expected continue and

has not the it to is 3 steps taken planned reduce eliminate and prevent reoccurrence

or to of the noncompliance

b The following shall included information which must reported within hours

be as be 24 1 Any unanticipated bypass which exceeds any effluent limitation permit

in the 2 Any upset which exceeds any effluent limitation permit and

in the 3 Violation a maximum daily discharge limitation any pollutants listed

of for of the by the

Director Part I permit reported within hours

in of the to be 24 c The Director may waive written report a case bycase basis oral report has

the on if the been received within hours

7 Other Noncompliance

The permittee shall report instances noncompliance reported under Part D and 6

all of not II 4,5 at time monitoring reports submitted The reports shall contain information listed Part

the are the at D6

8 Changes Discharge Toxic Substances Industrial Dischargers

in of for

The permittee shall notify Director soon she knows has reason believe

the as as he or to a That any activity has occurred will occur which would result discharge a routine

or in the in frequent basis any toxic pollutant which limited permit that discharge

or of is not in the if will exceed highest “notification levels” described CFR Part 122.42 a1

the of the in 40 b That any activity has occurred will occur which would result any discharge a

or in on infrequent basis a toxic pollutant which limited permit that nonroutineor of is not in the if discharge will exceed highest “notification levels” described CFR Part

the of the in 40 122.42 a2

9 Duty Provide Information

The permittee shall furnish Director within a reasonable time any information which

to the the

Director may request determine whether cause exists modifying revoking and reissuing

to for or terminating this permit determine compliance with this permit The permittee shall also

to or

ENPDES PermitAR0037842 Permit Number AR0037842

Page Part

10 of II

furnish Director upon request copies records required kept this permit

to the of to be by Information shall submitted form manner and time frame requested Director

be in the by the

Duty reapply

10 to

permittee wishes continue activity regulated this permit after expiration date

If the to an by the of this permit permittee must apply and obtain a new permit The complete application shall

the for submitted least 180 days before expiration date this permit The Director may grant

be at the of permission submit application less than 180 days advance but later than permit

to an in no the expiration date Continuation expiring permits shall governed regulations promulgated

of be by in APCEC Regulation No 6

Signatory Requirements

applications reports information submitted Director shall signed and certified

All or to the be

a permit applications shall signed follows

All be as 1 For a corporation a responsible corporate officer For the purpose this section a

by of

responsible corporate officer means i A president secretary treasurer vice president corporation charge a

or of the in of principal business function any other person who performs similar policy

or or decision making functions corporation

for the or The manager one more manufacturing production operation facilities

ii of or or provided manager authorized make management decisions which govern

the is to operation regulated facility including having explicit implicit duty

the of the the or

making major capital investment recommendations and initiating and directing

of other comprehensive measures assure long term environmental compliance with

to environmental laws and regulations manager can ensure that necessary

the the systems established actions taken gather complete and accurate

are or to information permit application requirements and where authority sign

for to documents been assigned delegated manager accordance with

has or to the in corporate procedures 2 For a partnership sole proprietorship a general partner proprietor respectively

or by or

or 3 a municipality State Federal other public agency either a principal

For or by executive officer ranking elected official For purposes this section a principal

or of executive officer a Federal agency includes

of i The chief executive officer agency

of the or A senior executive officer having responsibility overall operations a

ii for the of principal geographic unit agency

of the b reports required permit and other information requested Director shall

All by the by the be signed a person described above a duly authorized representative that person

by or by of A person a duly authorized representative only

is if 1 The authorization made writing a person described above

is in by 2 The authorization specified either individual a position having responsibility

an or for overall operation regulated facility activity such position plant

the of the or as the of

ENPDES PermitAR0037842 Permit Number AR0037842

Page Part

11 of II

manager operator a well a well field superintendent position equivalent

of or or of responsibility A duly authorized representative may thus either a named individual

be any individual occupying a named position and

or 3 The written authorization submitted Director

is to the c Certification Any person signing a document under this section shall make following

the

certification

“I certify under penalty law that this document and attachments were prepared under

of all my direction supervision accordance with a system designed assure that qualified personnel

or in to properly gather and evaluate information submitted Based inquiry person

the on my of the or persons who manage system those persons directly responsible gathering

the or for the information information submitted best my knowledge and belief true accurate

the is to the of and complete I aware that there significant penalties submitting false information

am are for including the possibility fine and imprisonment knowing violations.”

of for

Availability Reports

12 of

Except data determined confidential under CFR Part 2 and Regulation 6 reports

for to be 40 all prepared accordance with terms this permit shall available public inspection the

in the of be for at offices Department Environmental Quality required Regulations name and

of the of As by the the address any permit applicant permittee permit applications permits and effluent data shall

of or considered confidential

not be

Penalties Falsification Reports

13 for of

The Arkansas Air and Water Pollution Control Act provides that any person who knowingly makes any false statement representation certification any application record report plan

or in or other document filed required maintained under this permit shall subject civil

or to be be to penalties specified Part A2 and criminal penalties under authority Arkansas

in II or the of the Water and Air Pollution Control Act Act 472 1949 amended

of as

ENPDES PermitAR0037842 Permit number AR0037842

Page 1 Part

of III

PART

III OTHER CONDITIONS

1 The operator this wastewater treatment facility shall Industrial licensed State

of be by the of Arkansas accordance with Act 1103 1991 Act 556 1993 Act 211 1971 and

in of of of Regulation No 3 amended

2 accordance with CFR Parts 122.62 a 2 and 124.5 this permit may reopened

In 40 be for

modification revocation and reissuance require additional monitoring and effluent

or or to or

limitations when new information received that actual potential exceedance State

is or of water quality criteria and narrative criteria determined result

or are to be the of the permittee’s discharge s water body a Total Maximum Daily Load TMDL

to or is established revised the water body that were available time permit

or for not at the of issuance that would have justified application different permit conditions time

the of at the of permit issuance

3 Other Specified Monitoring Requirements

The permittee may use alternative appropriate monitoring methods and analytical instruments

other than specified Part I Section A permit without a major permit modification

as in of the under following conditions

the

• The monitoring and analytical instruments are consistent with accepted scientific

practices

• The requests shall submitted writing NPDES Section Water Division

be in to the of the ADEQ alternate method instrument

of the for use of the or • The method and instrument compliance with CFR 136 and

in or is 40

• associated devices installed calibrated and maintained insure accuracy

All are to the of

measurements and consistent with accepted capability that type device The

the are of of calibration and maintenance shall performed part permittee’s laboratory

be as of the Quality ControlQuality Assurance program

Upon written approval alternative monitoring method and analytical instruments these

of the or methods instruments must consistently utilized throughout monitoring period ADEQ

or be the must notified writing and permittee must receive written approval from ADEQ

be in the if the permittee decides return original permit monitoring requirements

to to the

4 WHOLE EFFLUENT TOXICITY TESTING 7DAY CHRONIC NOEC FRESHWATER

1 SCOPE AND METHODOLOGY

a The permittee shall test effluent toxicity accordance with

the for in the

provisions this section

APPLICABLE TO FINAL OUTFALL 101

E NPDES PermitAR0037842 Permit number AR0037842

Page 2 Part

of III

CRITICAL DILUTION 17

EFFLUENT DILUTION SERIES 7 101317 23

COMPOSITE SAMPLE TYPE Defined PART I

TEST SPECIESMETHODS CFR Part 136

APPLICABLE TO FINAL OUTFALL 401

CRITICAL DILUTION 40

EFFLUENT DILUTION SERIES 17 2330 40 54

COMPOSITE SAMPLE TYPE Defined PART I

TEST SPECIESMETHODS CFR Part 136

Ceriodaphnia dubia chronic static renewal survival and reproduction test Method 1002.0 EPA600 491002 most recent update thereof

or the This test should terminated when 60 surviving females

be of the in the control produce three broods end eight days whichever comes

at or the of

first

Pimephales promelas fathead minnow chronic static renewal 7day larval survival and growth test Method 1000.0 EPA600 4 002 most

91 or the recent update thereof A minimum five 5 replicates with eight 8

of organisms replicate must used control and each effluent

per be in the in dilution this test

b The NOEC Observed Effect Concentration defined greatest

No is as the effluent dilution and below which lethality that statistically different

at is from control effluent 95 confidence level does occur

the 0 at the not Chronic lethal test failure defined a demonstration a statistically

is as of

significant lethal effect test completion a species below

or at to test at the critical dilution

c This permit may reopened require whole effluent toxicity limits

be to chemical specific effluent limits additional testing and other

or appropriate actions address toxicity

d Test failure defined a demonstration statistically significant

is as of

lethal effects a test species below effluent critical

or sublethalor to at the dilution

E NPDES PermitAR0037842 Permit number AR0037842

Page 3 Part

of III

2 PERSISTENT LETHALITY The requirements this subsection apply only

when a toxicity test demonstrates significant lethal effects below critical

or at the

dilution Significant lethal effects herein defined a statistically significant

are as difference 95 confidence level between survival appropriate test

at the the of the organism a specified effluent dilution and control effluent

in the 0

a Part I Testing Frequency Other Than Monthly

i The permittee shall conduct a total two 2 additional tests

of for any species that demonstrates significant lethal effects below

or at

critical dilution The two additional tests shall conducted

the be monthly during next two consecutive months The permittee

the shall not substitute either two additional tests lieu

of the in of

routine toxicity testing The report shall prepared each

full be for test required this section accordance with procedures outlined

by in

Item 4 this section and submitted with period discharge

in of the monitoring report DMR permitting authority review

to the for

one both two additional tests demonstrates significant

ii or of the If lethal effects below critical dilution permittee shall

or at the the initiate Toxicity Reduction Evaluation TRE requirements

as specified Item 5 this section The permittee shall notify

in of ADEQ writing within 5 days failure any retest and

in of the of the

TRE initiation date will completion date first

be the test of the failed retest A TRE may also required due a

be be to

demonstration persistent significant sublethal effects

of or intermittent lethal effects below the critical dilution

or at or for failure perform required retests

to the

one both two additional tests demonstrates significant

iii If or of the lethal effects below critical dilution permittee shall

or at the the henceforth increase frequency testing this species once

the of for to

quarter life permit

per for the of the

The provisions Item 2 a suspended upon submittal

iv of are of the TRE Action Plan

b Part I Testing Frequency Monthly

E NPDES PermitAR0037842 Permit number AR0037842

Page 4 Part

of III

The permittee shall initiate Toxicity Reduction Evaluation TRE

the requirements specified Item 5 this section when any two three

as in of of

consecutive monthly toxicity tests exhibit significant lethal effects

or at below critical dilution A TRE may also required due a

the be be to demonstration persistent significant sub lethal effects intermittent

of or

lethal effects below critical dilution failure perform

or at the or for to the required retests

3 REQUIRED TOXICITY TESTING CONDITIONS

a Test Acceptance

The permittee shall repeat a test including control and effluent

the all dilutions procedures and quality assurance requirements defined

if the in test methods this permit satisfied including following

the or in are the not

additional criteria

i The toxicity test control effluent must have survival equal

0 to greater than 80

The mean number Ceriodaphnia dubia neonates produced

ii of per surviving female control effluent must more

15 in the 0 be or

60 surviving control females must produce three broods

iii of the

The mean weight surviving fathead minnow larvae

iv dry of at the end 7 days control effluent must 0.25

of the in the 0 be mg per larva greater

v The percent coefficient variation between replicates shall

of be 40 less control effluent for young surviving

or in the 0 the of females Ceriodaphnia dubia reproduction test growth

in the the and survival endpoints fathead minnow test

of the

The percent coefficient variation between replicates shall

vi of be 40 less critical dilution unless significant lethal

or in the or nonlethal effects exhibited for young surviving females

are the of the Ceriodaphnia dubia reproduction test growth and

in the survival endpoints fathead minnow test

of the

Test failure may construed reported invalid due a

not be or as to coefficient variation value greater than 40 A repeat test shall

of of be conducted within required reporting period any test determined

the of to invalid

E NPDES PermitAR0037842 Permit number AR0037842

Page 5 Part

of III

b Statistical Interpretation

i For Ceriodaphnia dubia survival test statistical analyses

the the

used determine there a significant difference between

to if is the control and critical dilution shall Fisher's Exact Test

the be as described EPA600 4 002 most recent update thereof

in 91 or the

For Ceriodaphnia dubia reproduction test and fathead

ii the the

minnow larval survival and growth test statistical analyses

the used determine there a significant difference between

to if is the

control and critical dilution shall accordance with

the be in the methods determining the No Observed Effect Concentration

for NOEC described EPA600 4 002 most recent

as in 91 or the update thereof

conditions Test Acceptability met Item 3 a above

iii If the of are in and the percent survival the test organism equal greater

or of is to than 80 critical dilution concentration and lower

in the all

dilution concentrations test shall considered a passing

the be to be test and permittee shall report NOEC less than

the an of not the critical dilution DMR reporting requirements found Item

for the in 4 below

c Dilution Water

i Dilution water used toxicity tests will receiving

in the be water collected close the point discharge

as to of as unaffected discharge The permittee shall

possiblebut by the substitute synthetic dilution water similar pH hardness

and alkalinity closest downstream perennial water

to the for

A toxicity tests conducted effluent discharges receiving

on to water classified intermittent streams and

B toxicity tests conducted effluent discharges where

on no receiving water available due zero flow conditions

is to

receiving water unsatisfactory a result instream

ii the is as of If

toxicity fails fulfill test acceptance criteria Item 3a

to the of the permittee may substitute synthetic dilution water receiving

for the water subsequent tests provided unacceptable receiving

in all the

water test met following stipulations

the

E NPDES PermitAR0037842 Permit number AR0037842

Page 6 Part

of III

A a synthetic dilution water control which fulfills test

the acceptance requirements Item 3a was run concurrently

of with receiving water control

the

B test indicating receiving water toxicity has been carried

the completion i e 7 days

out to

the permittee includes test results indicating receiving

C all

water toxicity with full report and information required

the Item 4 below and

D synthetic dilution water shall have a pH hardness and

the alkalinity similar that receiving water closest

to of the or downstream perennial water adversely affected

not by the discharge provided magnitude these parameters will

the of cause toxicity synthetic dilution water

not in the

d Samples and Composites

i The permittee shall collect a minimum three flow weighted

of composite samples from outfall s listed Item 1a above

the at

The permittee shall collect second and third composite samples

ii for use during 24 hour renewals each dilution concentration

of for

each test The permittee must collect composite samples such

the that effluent samples representative any periodic episode

the are of

chlorination biocide usage other potentially toxic substance

of or discharged intermittent basis

on an

The permittee must collect composite samples that

iii the so the

maximum holding time any effluent sample shall exceed

for not 72 hours The permittee must have initiated toxicity within

the test 36 hours after collection last portion first composite

the of the of the

sample Samples shall chilled 4 degrees Centigrade during

be to collection shipping and storage

flow from outfall s being tested ceases during

iv the the the If collection effluent samples the requirements the minimum

of for

number effluent samples minimum number effluent

of the of and sample holding time waived during that sampling portionsthe are period However permittee must collect effluent composite

the an sample volume during period discharge that sufficient

the of is to complete required toxicity tests with daily renewal effluent

the of

When possible effluent samples used toxicity tests shall

the for the collected separate days discharge occurs over multiple

be on if the

E NPDES PermitAR0037842 Permit number AR0037842

Page 7 Part

of III

days The effluent composite sample collection duration and

the

static renewal protocol associated with abbreviated sample

the collection must documented full report required Item 4

be in the in

this section

v MULTIPLE OUTFALLS provisions this section

If the of are

applicable multiple outfalls permittee shall combine

to the the composite effluent samples proportion the average flow from

in to outfalls listed Item 1 a above day sample was

the in for the the

collected The permittee shall perform toxicity test

the on the flow weighted composite outfall samples

of the

The permittee shall allow sample dechlorinated the

vi not the to be at laboratory time sample collection permittee shall

At the of the measure TRC effluent The measured concentration

the of the of TRC each sample shall included report submitted

for be in the lab permittee

by the

4 REPORTING

a The permittee shall prepare a full report results tests

of the of all

conducted pursuant this section accordance with Report

to in the Preparation Section EPA600 491 002 the most current publication

of or

every valid invalid toxicity test initiated whether carried

for or to

completion not The permittee shall retain each report pursuant

or full to provisions PART C7 this permit The permittee shall submit

the of II of

full reports upon specific request Department For any test

the of the which fails considered invalid which terminated early any

is or is for reason full report must submitted review

the be for

b A valid test each species must reported DMR during each

for be on the

reporting period specified PART I this permit unless permittee

in of the is performing a TRE which may increase frequency testing and

the of reporting Only ONE biomonitoring data each species

set of for is to be recorded DMR each reporting period The data submitted

on the for should reflect LOWEST survival results each species during

the for the reporting period invalid tests repeat tests invalid tests and

All for retests tests previously failed performed during the reporting period

for must attached DMR ADEQ review

be to the for

c The permittee shall submit results each valid toxicity test a

the of on DMR that reporting period accordance with PART D4 this

for in II of permit follows below Submit retest information clearly marked

as as such with following DMR Only results valid tests

the of are to be reported DMR

on the

E NPDES PermitAR0037842 Permit number AR0037842

Page 8 Part

of III

i Pimephales promelas fathead minnow

A Observed Effect Concentration NOEC

If the No for survival less than critical dilution enter a 1

is the otherwise enter a 0 Parameter No TLP6C

for

Observed Effect Concentration NOEC

B If the No for growth less than critical dilution enter a 1

is the otherwise enter a 0 Parameter No TGP6C

for

C Report NOEC value survival Parameter No

the for TOP6C

D Report highest critical dilution control Coefficient

the or Variation Parameter No TQP6C

E Report NOEC value growth Parameter No TPP6C

the for

Ceriodaphnia dubia

A NOEC survival less than critical dilution

If the for is the enter a 1 otherwise enter a 0 Parameter No

for TLP3B

B Observed Effect Concentration NOEC

If the No for

reproduction less than critical dilution enter a

is the 1 otherwise enter a 0 Parameter No TGP3B

for

B Report NOEC value survival Parameter No

the for TOP3B

C Report higher critical dilution control Coefficient

the or Variation Parameter No TQP3B

E Report NOEC value reproduction Parameter No

the for TPP3B

5 Monitoring Frequency Reduction

a The permittee may apply a testing frequency reduction upon

for the

successful completion first four consecutive quarters testing

of the of for one both test species with lethal sublethal effects demonstrated

or no or

below critical dilution without a major modification granted

or at the If monitoring frequency that test species may reduced less

the for be to not

E NPDES PermitAR0037842 Permit number AR0037842

Page 9 Part

of III

than once year less sensitive species usually fathead

per for the the

minnow and less than twice per year more sensitive test

not for the species usually Ceriodaphnia dubia

the

b CERTIFICATION The permittee must certify writing that test

in no failures have occurred and that tests meet test acceptability criteria

all all item 3a above addition permittee must provide a with each

in In the list test performed including test initiation date species NOECs lethal and

for

sublethal effects and maximum coefficient variation

the of for the

controls Upon review and acceptance this information Department

of the will issue a letter confirmation monitoring frequency reduction

of of the A copy letter will forwarded Permit Compliance System

of the be to the section update permit reporting requirements

to the

c SUBLETHAL FAILURES during first four quarters testing

If the of sublethal effects demonstrated a test species two monthly retests

are to

required addition quarterly testing required that species until

are In is for the effluent passes both the lethal and sub lethal test endpoints the

for

affected species four consecutive quarters Monthly retesting

for is not required permittee performing a TRE

if the is

d SURVIVAL FAILURES any test fails survival endpoint any

If the at time during the life this permit two monthly retests required and the

of are

monitoring frequency affected test species shall increased

for the be to

once quarter until permit issued Monthly retesting

per the is re is not required permittee performing a TRE

if the is

e This monitoring frequency reduction applies only until expiration date

the this permit which time monitoring frequency both test species

of at the for reverts once quarter until permit issued

to per the is re

6 TOXICITY REDUCTION EVALUATION TRE

a Within ninety 90 days confirming lethality retests permittee

of in the the shall submit a Toxicity Reduction Evaluation TRE Action Plan and

Schedule conducting a TRE The TRE Action Plan shall specify the

for approach and methodology used performing TRE A Toxicity

to be in the Reduction Evaluation investigation intended determine those

is an to

actions necessary achieve compliance with water quality based effluent

to limits reducing effluent's toxicity acceptable level A TRE

by an to an is defined a stepwise process which combines toxicity testing and

analyses physical and chemical characteristics a toxic effluent

of the of to

identify constituents causing effluent toxicity and treatment

the or

methods which will reduce effluent toxicity The TRE Action Plan

the

shall lead successful elimination effluent toxicity critical

to the of at the dilution and include the following

E NPDES PermitAR0037842 Permit number AR0037842

Page Part

10 of III

i Specific Activities The plan shall detail specific approach

the the permittee intends utilize conducting TRE The approach

to in the

may include toxicity characterizations identifications and

confirmation activities source evaluation treatability studies

or alternative approaches When permittee conducts Toxicity

the

Characterization Procedures permittee shall perform multiple

the characterizations and follow procedures specified the

the in

documents Methods Aquatic Toxicity Identification

for EvaluationsPhase I Toxicity Characterization Procedures EPA600 6 003 and Toxicity Identification Evaluation

91 Characterization Chronically Toxic Effluents Phase I

of EPA600 6 005F alternate procedures When the

91 or permittee conducts Toxicity Identification Evaluations and

Confirmations permittee shall perform multiple identifications

the and follow methods specified documents Methods

the in the for

Aquatic Toxicity Identification Evaluations Phase Toxicity

II Identification Procedures Samples Exhibiting Acute and

for Chronic Toxicity EPA600 R92080 and Methods Aquatic

for

Toxicity Identification Evaluations Phase Toxicity

III Procedures Samples Exhibiting Acute and Chronic

Confirmationfor Toxicity EPA 600 R 081 appropriate

92 as

The documents referenced above may obtained through

be the National Technical Information Service NTIS phone 800

by at 5536847 writing

or by

US Department Commerce

of National Technical Information Service

5285 Port Royal Road

Springfield VA 22161

Sampling Plan eg locations methods holding times chain

ii of custody preservation etc The effluent sample volume collected

tests shall adequate perform toxicity test toxicity

for all be to the

characterization identification and confirmation procedures and

conduct chemical specific analyses when a probable toxicant has

been identified

Where permittee identified suspects specific pollutant s

the has or and source s effluent toxicity permittee shall conduct

or of the concurrent with toxicity testing chemical specific analyses

for the identified and suspected pollutant s and sources effluent

or or of

toxicity Where lethality was demonstrated within hours test

48 of initiation each composite sample shall analyzed independently

E NPDES PermitAR0037842 Permit number AR0037842

Page Part

11 of III

Otherwise permittee may substitute a composite sample

the comprised equal portions individual composite samples

of of the the chemical specific analysis

for

Quality Assurance Plan eg QAQC implementation corrective

iii actions etc and

Project Organization e project staff project manager

iv g consulting services etc

b The permittee shall initiate TRE Action Plan within thirty 30 days

the of

plan and schedule submittal The permittee shall assume risks

all for failure achieve required toxicity reduction

to the

c The permittee shall submit a quarterly TRE Activities Report with

the Discharge Monitoring Report months January April July and

in the of

October containing information toxicity reduction evaluation activities

on including

i any data and substantiating documentation which identifies

or the pollutant s and sources effluent toxicity

or of

any studiesevaluations and results the treatability

ii on of the facility'seffluent toxicity and

any data which identifies effluent toxicity control mechanisms that

iii

will reduce effluent toxicity level necessary meet

to the to no significant lethality critical dilution

at the

d The permittee shall submit a Final Report Toxicity Reduction

Activities later than twenty eight 28 months from confirming

Evaluationno lethality retests which provides information pertaining

in the to the specific control mechanism selected that will when implemented result

reduction effluent toxicity significant lethality critical

of to no at the dilution The report will also provide a specific corrective action schedule

implementing selected control mechanism

for the

Quarterly testing during TRE a minimum monitoring requirement EPA

the is

recommends that permittees required perform a TRE rely quarterly

to not on testing alone ensure success TRE and that additional screening tests

to in the be

performed capture toxic samples identification toxicants Failure

to for of to identify specific chemical compound causing toxicity test failure will

the normally result a permit limit whole effluent toxicity limits federal

in for per regulations CFR 122.44 d1v

at 40

E NPDES PermitAR0037842 Permit number AR0037842

Page Part

12 of III

5 Storm Water Pollution Plans

Storm water runoff commingling with other process wastewater discharged from Outfall 101

shall managed accordance with Best Management Practices BMPs form a

be in the in the of pollution prevention plan SWPPP required Arkansas Industrial General Storm Water

by the Permit ARR000000 control quality storm water discharges associated with

to the of industrial activity based CFR 122.44 k

on 40

6 There shall discharge polychlorinated biphenyl transformer fluid

be no of

7 The term “ Total Residual Chlorine” means value obtained using amperometric method

the

total residual chlorine described CFR Part 136

for in 40

Total Residual Chlorine may discharged from any unit more than two hours

not be for per

day any one day unless discharger demonstrates permitting authority that

in the to the discharge more than two hours required macroinvertebrate control

for is for

8 The term “low volume waste sources” means taken collectively from one source

as if

wastewater from sources except those which specific limitations otherwise

all for are established Low volume sources include limited wastewater from wet

not are but to scrubber pollution control systems exchange water treatment system water treatment

air ion

evaporator blowdown laboratory and sampling wastes boiler blowdown floor drains

cooling tower basin cleaning wastes and recirculating house service water systems Sanitary

and conditioning wastes not included

air are

9 The term “ bottom ash” means that drops furnace steam furnace

the ash out of the gas in the and economizer sections Economizer ash included when collected with bottom

in the is it is ash

The term “coal pile runoff” means rainfall from through any coal storage pile

10 the or

The term “once through cooling water” means water passed through main cooling

11 the condensers one two passes purpose removing waste heat

in or for the of

The permittee shall comply with Cooling Water Intake regulations found Title Code

12 the in 40 Federal Regulations Part 125 Subpart J These regulations include but are not limited

of to following provisions

the

c The permittee shall submit two copies Proposal Information Collection

of the for to the NPDES Branch Water Division prior start information collection

of the to the of

activities and

d The permittee shall submit two copies the completed Comprehensive Demonstration

of Study NPDES Branch Water Division prior January 7 2008

to the of the to or on or

before federal deadline that EPA may reestablish complying with

the the for the requirements CFR 125 Subpart J The permittee shall meet other applicable

of 40 all

requirements this regulation

E NPDES PermitAR0037842 Permit number AR0037842

Page Part

13 of III

E NPDES PermitAR0037842 Permit number AR0037842

Page 1 Part

of IV

PART

IV DEFINITIONS

definitions contained Section 502 Clean Water Act shall apply this permit and

All in of the to are incorporated herein reference Additional definitions words phrases used this permit

by of or in follows

are as

1 “Act” means Clean Water Act Public Law 217 USC 1251 seq amended

the 95 33 et as 2 “Administrator” means Administrator US Environmental Protection Agency

the of the 3 “Applicable effluent standards and limitations” means State and Federal effluent

all standards and limitations which a discharge subject under Act including limited

to is the but not effluent limitations standards performance toxic effluent standards and prohibitions and

to of pretreatment standards

4 “Applicable water quality standards” means water quality standards which a

all to discharge subject under federal Clean Water Act and which has been a approved

is the or permitted remain effect Administrator following submission Administrator

to in by the to the pursuant Section 303 a the Act b promulgated the Director pursuant Section

to of or by to 303b 303 c Act and standards promulgated under regulation No 2 amended

or of the as

regulation establishing water quality standards surface waters State Arkansas

for of the of 5 “Bypass” means intentional diversion waste streams from any portion a treatment

the of of facility

6 “Daily Discharge” means discharge a pollutant measured during a calendar day any

the of or

24hour period that reasonably represents calendar day purposes sampling

the for of

Mass Calculations For pollutants with limitations expressed terms mass “daily

in of the discharge” calculated total mass pollutant discharged over sampling day

is as the of the

Concentration Calculations For pollutants with limitations expressed other units

in of measurement determination concentration made using a composite sample shall

of be the concentration composite sample When grab samples used “daily discharge”

of the are the determination concentration shall arithmetic average weighted flow value

of be the by of all the samples collected during that sampling day using following formula where daily

by the C concentration Fdaily flow and nnumber daily samples daily average discharge

C1F1 C2F2+…CnFn

F1 Fn F2 …

7 Monthly average means highest allowable average “daily discharges” over a calendar

the of month calculated sum “daily discharges” measured during a calendar month divided

as the of all

number “daily discharges” measured during that month For Fecal Coliform Bacteria

by the of FCB report monthly average see 30 day average below

the 8 “Daily Maximum” discharge limitation means highest allowable “daily discharge” during

the calendar month The 7day average fecal coliform bacteria geometric mean

the for is the of the values effluent samples collected during calendar week colonies 100

of all the in ml 9 “Department” means Arkansas Department Environmental Quality ADEQ

the of

E NPDES PermitAR0037842 Permit number AR0037842

Page 2 Part

of IV

“Director” means Administrator US Environmental Protection Agency and

10 the of the or Director Arkansas Department Environmental Quality

the of the of “Grab sample” means individual sample collected less than minutes conjunction

11 an in 15 in with instantaneous flow measurement

“Industrial User” means a nondomestic discharger identified CFR 403 introducing

12 as in 40 pollutants a publicly owned treatment works

to “National Pollutant Discharge Elimination System” means national program

13 the for issuing modifying revoking and reissuing terminating monitoring and enforcing permits and imposing and enforcing pretreatment requirements under sections 307 402 318 and 405

of the Clean Water Act “POTW” means a Publicly Owned Treatment Works

“ Severe property damage” means substantial physical damage property damage

15 to to the treatment facilities which causes them become inoperable substantial and permanent loss

to or natural resources which can reasonably expected occur absence a bypass

of be to in the of Severe property damage does mean economic loss caused delays products

not by in “APCEC” means Arkansas Pollution Control and Ecology Commission

16 the

“ Sewage sludge” means solids residues and precipitate separated from created

17 the or in sewage unit processes a publicly owned treatment works Sewage used this

by the as in definition means any wastes including wastes from humans households commercial establishments industries and storm water runoff that discharged otherwise enter a

or are to publicly owned treatment works

“7day average” discharge limitation other than fecal coliform bacteria highest

18 for is the allowable arithmetic means the values effluent samples collected during calendar

of for all the week The 7day average fecal coliform bacteria geometric mean values

for is the of the of all effluent samples collected during calendar week colonies 100 mlThe DMR should report

the in highest 7day average obtained during calendar month For reporting purposes 7day

the the the average values should reported occurring month which Saturday

be as in the in the of the calendar week falls

in “ day average” other than fecal coliform bacteria arithmetic mean daily

19 30 for is the of the values effluent samples collected during a calendar month calculated sum

for all as the of all daily discharges measured during a calendar month divided number daily discharges

by the of measured during that month The 30 day average fecal coliform bacteria geometric

for is the mean values effluent samples collected during a calendar month

of the for all For Fecal Coliform Bacteria FCB report monthly average a 30 day geometric mean

the as in colonies 100 ml

per “24 hour composite sample” consists a minimum effluent portions collected

20 of of 12 at equal time intervals over 24hour period and combined proportional flow a sample

the to or collected frequent intervals proportional flow over the 24hour period

at to “ hour composite sample” consists effluent portions collected closer together

21 12 of 12 no than one hour and composited according flow The daily sampling intervals shall include

to the highest flow periods “6hour composite sample” consists effluent portions collected closer together

22 of six no than one hour with first portion collected earlier than 10 a and composited

the no 00 m according flow

E NPDES PermitAR0037842 Permit number AR0037842

Page 3 Part

of IV

“3hour composite sample” consists three effluent portions collected closer together

23 of no than one hour with first portion collected earlier than a and composited

00 the no 10 m according flow

to “Treatment works” means any devices and systems used storage treatment recycling

24 in and reclamation municipal sewage and industrial wastes a liquid nature implement

of of to section 201 Act necessary recycle reuse water most economic cost over

of the or to at the the estimated life works including intercepting sewers sewage collection systems pumping

of the power and other equipment and alterations thereof elements essential provide a reliable

to recycled supply such standby treatment units and clear well facilities and any works

as including site acquisition land that will integral part treatment process

of the be an of the or is used ultimate disposal residues resulting from such treatment

for of “Upset” means exceptional incident which there unintentional and temporary

25 an in is noncompliance with technology based permit effluent limitations because factors beyond the

of reasonable control permittee Any upset does include noncompliance extent

of the not to the caused operational error improperly designed treatment facilities lack preventive

by or maintenance careless improper operations

or of “For Fecal Coliform Bacteria” a sample consists one effluent grab portion collected

26 of during a 24 hour period peak loads For Fecal Coliform Bacteria FCB report the monthly

at average a 30 day geometric mean colonies per 100

as in ml

“ Dissolved oxygen limit” shall defined follows

27 be as a When limited permit a monthly average minimum shall mean lowest acceptable

in the as the monthly average value determined averaging samples taken during calendar month

by all the b When limited permit instantaneous minimum value shall mean that value

in the as an no measured during reporting period may fall below stated value

the the The term “MGD” shall mean million gallons day

28 per

The term “mgl “shall mean milligrams liter parts million ppm

29 per or per

The term “_g shall mean micrograms per liter parts per billion ppb

30 l” or 31 The term “cfs” shall mean cubic feet per second

The term “ppm” shall mean part per million

32 The term “su.” shall mean standard units

33 Monitoring and Reporting

34 When a permit becomes effective monitoring requirements immediate period

are of the of the permit effective date Where the monitoring requirement effluent characteristic

for an is

Monthly more frequently Discharge Monitoring Report shall submitted 25th

or the be by the of month following sampling Where monitoring requirement effluent

the the the for an characteristic Quarterly SemiAnnual Annual Yearly Discharge Monitoring report

is or the shall submitted 25th month following monitoring period end date

be by the of the the 35 Instantaneous maximum value shall mean that value measured during the reporting

no period may above stated value

be the

E NPDES PermitAR0037842 Permit number AR0037842

Page 4 Part

of IV

MONTHLY

defined a calendar month any portion a calendar month monitoring requirement

is as or of for frequency oncemonth more frequently

of or

QUARTERLY

1 defined a fixed calendar quarter any part fixed calendar quarter a

is as or of the for

effluent characteristic with a measurement frequency oncequarter Fixed calendar nonseasonalof quarters are January through March April through June July through September and October through December

or 2 defined a fixed three month period any part fixed three month period

or is as or of the of dependent upon seasons specified permit a seasonal effluent characteristic with a

the in the for monitoring requirement frequency once quarter that does not coincide with fixed calendar

of the quarter Seasonal calendar quarters May through July August through October November

are through January and February through April

SEMI ANNUAL

defined fixed time periods January through June and July through December any

is as the or portion thereof effluent characteristic with a measurement frequency once 6 months

for an of or twice year

ANNUAL YEARLY

defined a fixed calendar year any portion fixed calendar year effluent

is as or of the for an characteristic parameter with a measurement frequency onceyear A calendar year

or of is January through December any portion thereof

E NPDES PermitAR0037842 Final Fact Sheet

For renewal final NPDES Permit Number AR0037842 discharge Waters the State

of to to of

1 PERMITTING AUTHORITY

The issuing office

Arkansas Department Environmental Quality

of 8001 National Drive

Post Office Box 8913

Little Rock Arkansas 72219 8913

2 APPLICANT

The applicant

American Electric Power

Southwestern Electric Power Company SWEPCO Flint Creek Power Plant 21797 SWEPCO Plant Road Gentry AR 72734

3 PREPARED BY

The permit was prepared

Marysia Jastrzebski PE NPDES Branch Water Division

4 DATE PREPARED

The permit was prepared January 26 2006

5 PREVIOUS PERMIT ACTIVITY

Effective Date December 1 2000 Modification Date NA Expiration Date November 2005

The permittee submitted a permit renewal application 04 2005 proposed that

on 29 It is current NPDES permit reissued a 5year term accordance with regulations

the be for in promulgated CFR Part 122.46 a

at 40

E NPDES PermitAR0037842 Page 2 Fact Sheet

of Permit No AR0037842

6 RECEIVING STREAM SEGMENT AND DISCHARGE LOCATION

The outfalls located following coordinates

are at the

Outfall 001 Latitude 36 14’ 00” Longitude 94 02”

33’ Outfall 101 Latitude 36 15’ 03” Longitude 94 35”

31’ Outfall 401 Latitude 36 15’ 27” Longitude 94 32”

31’

The receiving waters named

SWEPCO Reservoir thence Little Flint Creek thence Flint Creek Segment

to to in 3J of Arkansas River Basin The receiving stream a Water State classified

the is of the for primary contact recreation raw water source public industrial and agricultural water

for

supplies propagation desirable species fish and other aquatic life and other

of of compatible uses

7 303 d List and Endangered Species Considerations

A 303d List

The receiving stream listed 303 d list Therefore permit action needed

is not on the no is

B Endangered Species

comments were received from US Fish and Wildlife Service USFWS

No the

8 OUTFALL AND TREATMENT PROCESS DESCRIPTION

The following a description facility described application

is of the in the

Average Flow

Outfall 001 varies from MGD MGD based last two years DMR data

1.7 to 9.0 on the Outfall 101 9.83 MGD based highest monthly average flow during last

on the the two years

Outfall 401 406.08 MGD based highest monthly average flow during last

on the the two years

Type treatment

Outfall 001 none

Outfall 101 settling and neutralization

Outfall 401 chlorination

Discharge Description

E NPDES PermitAR0037842 Page 3 Fact Sheet

of Permit No AR0037842

Outfall 001 discharge from SWEPCO Reservoir

the Outfall 101 bottom ash discharge low volume wastewater and storm water runoff

including coal pile runoff treated municipal wastewater from City

the of Gentry The City Gentry operates under NPDES permit No

of AR0020184

Outfall 401 once through cooling water

9 APPLICANT ACTIVITY

Under standard industrial classification SIC code 4911 applicant's activity

the the is the operation a steam electric power generating plant

SEWAGE SLUDGE PRACTICES

There sewage sludge generated this facility

is no in

PERMIT CONDITIONS

The Arkansas Department Environmental Quality has made a tentative determination

of to issue a permit discharge described application Permit requirements based

for the in the are NPDES regulations CFR Parts 122 124 and Subchapter N and regulations

on 40 promulgated pursuant Arkansas Water and Air Pollution Control Act Act 472 1949

to the of amended Ark Code Ann 84101 seq

as et

a Final Effluent Limitations

1 Conventional and Toxic Pollutants

OUTFALL 001 –SWEPCO Reservoir discharge

Effluent Characteristics Discharge Limitations Monitoring Requirements

Mass Concentration lbsday unless mgl unless Frequency Sample Type

otherwise otherwise specified

specified

Monthly Daily Monthly Daily Avg Max Avg Max Flow mgd N A N A Report Report Continuous Record

Minimum Maximum N A NA Once week Grab pH su su

6.0 9.0

E NPDES PermitAR0037842 Page 4 Fact Sheet

of Permit No AR0037842

OUTFALL 101 –combined wastewater bottom ash discharge low volume wastewater and storm water runoff including coal pile runoff and treated municipal wastewater from City Gentry

the of

Effluent Characteristics Discharge Limitations Monitoring Requirements

Mass Concentration lbsday unless mgl unless Frequency Sample Type otherwise otherwise specified

specified

Monthly Daily Monthly Daily Avg Max Avg Max Flow mgd N A N A Report Report Continuous Record Total Suspended Solids TSS N A N A Once week Grab

43 25 Once Oiland Grease O G N A N A 6 8 Grab 2 months Minimum Maximum N A N A Once week Grab pH su su

6.0 9.0 24 Chronic Biomonitoring N A N A See Page Below once quarter hr 16 composite

OUTFALL 401 –once through cooling water

Effluent Characteristics Discharge Limitations Monitoring Requirements

Mass Concentration lbsday unless mgl unless Frequency Sample

otherwise specified otherwise specified Type

Monthly Avg Daily Monthly Daily Max Max Avg Flow mgd N A N A 450 MGD 450 MGD Continuous Record

Total Residual 0.2 mgl N A 62.6 N A Once week Grab ChlorineTRC Inst Max Temperature N A N A N A 129.2 F Continuous Record Minimum Maximum N A N A Once week Grab pH 6.0 su 9.0 su 24 Chronic Biomonitoring N A N A See Page Below once quarter hr 16 composite

2 Solids Foam and Free Oil There shall discharge distinctly visible

be no of solids scum foam a persistent nature nor shall there any formation

or of be of

slime bottom deposits sludge banks visible sheen Sheen means

or No an

iridescent appearance surface water

on the of the

E NPDES PermitAR0037842 Page 5 Fact Sheet

of Permit No AR0037842

BASIS FOR PERMIT CONDITIONS

The following explanation derivation conditions final permit and

is an of the of the of the the reasons them the case notices intent deny terminate reasons suggesting

for or in of of to or tentative decisions required under CFR 124.7 1413 April 1 1983

the as 40 48 FR

A Technology Based versus Water Quality Based Effluent Limitations and Conditions

Following regulations promulgated CFR Part 122.44 1 2 final permit limits

at 40 ii the based either technology based effluent limits pursuant CFR Part 122.44 a

are on to 40 or on State water quality standards and requirements pursuant CFR Part 122.44 d

to 40 whichever more stringent

are

B Technology Based Effluent Limitations and Conditions

Regulations promulgated CFR Part 122.44 a require technology based effluent

at 40 limitations placed NPDES permitsbased effluent limitations guidelines where

to be in on applicable Best Professional Judgment BPJ absence guidelines a

on in the of or on combination the two

1 General Comments

Regulations promulgated CFR Part 122.44 a require technology based effluent

at 40 limitations placed NPDES permits based effluent limitations guidelines where

to be in on applicable Best Professional Judgment BPJ absence guidelines a

on in the of or on combination two

of the

2 Applicable Effluent Limitations Guidelines

Outfall 001

The final permit does establish any technology based effluent limitations

not

Outfall 101

Discharges from facilities this type covered Federal effluent limitations

of are by the

guidelines promulgated under CFR Part 423 Steam Electric Power Generating

40 of the Point Source Category

The technology based effluent limitations Total Suspended Solids and and Grease

for Oil have been based current NPDES permit and CFR Part 122.44 al They

on the 40 are consistent with CFR Part 423.12 b3 and CFR Part 423.12 b4

40 40

These limits were originally established 1989 and included the NPDES permit No

in in AR0037842 which was effective November 1 1989 They have been continued

on in all permits renewed since that time based antibacksliding regulations contained

on in 40

E NPDES PermitAR0037842 Page 6 Fact Sheet

of Permit No AR0037842

CFR122.44 l The following various wastestreams subject co treatment 1 are to in the

ponds low volume waste hydrovactor wastewater demineralizer water boiler

ash blowdown etc coal pile runoff bottom ash transport wastewater and stormwater

Some these wastestreams are categorical wastestreams regulated under Steam

of the

Electric Power Generating Point Source Category some unregulated streams

are

contributing solids and and grease and some just dilution streams Therefore

or oil are flow weighted concentrations mass limitations must included permit

or be in the to ensure that permit consistent with CFR 423.12 b12 The effluent limitations

the is 40 TSS and G discharge from co treatment facility ash pond were

for O for the the determined accordance with CFR 423.12 b3 423b4 and 423.12 b9

in 40

requirements and EPA’s “Guidance NPDES Permits Issued Steam Electric Power

for to Plants” dated August 2 1985 The detailed calculation can found Fact Sheet

be in the associated with NPDES Permit No AR0037842 which became effective

the on November 1 1989

Outfall 401

The technology based effluent limitations Total Residual Chlorine have been based

for on current NPDES permit and CFR Part 122.44 al They consistent with

the 40 are 40 CFR Part 423.13 b1

Additionally July 9 2004 EPA published final regulations prescribing how

on its “existing large volume power plants” should comply with Section 316 b Clean

of the Water Act This rule became effective September 7 2004 For most large volume

on existing power plants flow _ MGD this rule requires detailed studies and other

information establish what intake structure technology other measures will used

to or be comply with Section 316 b Ordinarily this material submitted with

to is to be the

facility’s next application renewal NPDES permit However permits that

for of its for expire less than four years after rule was published i e before July 7 2008 the

the operator may have three and ahalf years submit required information

up to to the as long submitted “ expeditiously practicable” This permit will include a special

as it as as is condition which requires permittee submit information required

the to all the as by 40 CFR 125.95 January 7 2008

3 Process wastewater Outfalls 101 and 401

The present technology based limits and monitoring requirements continued based

are on previous NPDES permit CFR Part 423 and CFR Part 122.44 al

the 40 40

Outfall 401once through cooling water

There shall discharge polychlorinated biphenyls transformer fluid consistent

be no of with CFR 432.12 b2

Total residual chlorine may not discharged from any single generating unit more

be for than two hours day unless discharger demonstrates permitting authority that

per the to the

E NPDES PermitAR0037842 Page 7 Fact Sheet

of Permit No AR0037842

discharge more than two hours required macroinvertebrate control

for is for

Simultaneous multiunit chlorination permitted

Technology based mass loading limits chlorine have been calculated based the

for on

present technology based concentration limits and maximum allowable flow 450

the of MGD These limitations continued from previous permit

are the

4 Stormwater runoff

Storm water runoff commingling with other process wastewater discharged from Outfall

101 shall managed accordance with Best Management Practices BMPs

be in the in the form a pollution prevention plan SWPPP required Arkansas Industrial General

of by the

Storm Water Permit ARR000000 control quality storm water discharges

to the of associated with industrial activity based CFR 122.44

on 40 k

C State Water Quality Numerical Standards Based Limitations

1 Conventional and Non Conventional Pollutants

Outfalls 001 101 and 401

The effluent limitations based current permit and CFR Part

for pH are on the 40 122.44 l They consistent with Chapter 5 Section 2.504 Regulation No 2

are of as amended

Sulfates Outfall 101

A requirement monitoring and reporting Sulfates deleted A review DMR

for of is of the indicates that there potential violations Arkansas Water Quality Standards

is no of of the Sulfates

for

Temperature Outfall 401

The effluent limitation Temperature are based the current permit and CFR Part

for on 40 122.44 l They consistent with Specific Standards SWEPCO Reservoir a are the for as contained Regulation No 2 amended

in as

D Toxics PollutantsPriority Pollutant Scan PPS

Arkansas Water Quality Standards

1 General Comments

Effluent limitations and conditions established the final permit are compliance

or in in with Arkansas Water Quality Standards and applicable Water Quality

the the Management Plan

E NPDES PermitAR0037842 Page 8 Fact Sheet

of Permit No AR0037842

2 Post Third Round Policy and Strategy

Section 101 the Clean Water Act CWA states that national policy that the

of it the is

discharge toxic pollutants toxic amounts prohibited...” insure that CWA's

of in be To the prohibitions toxic discharges met EPA issued a Policy Development

on are has for the Water Quality Based Permit Limitations Toxic Pollutants 9016 9019

of by 49 FR 3984 support national policy Region 6 adopted Policy post Third

In of the the for Round NPDES Permitting and Post Third Round NPDES Permit Implementation

the Strategy October 1 1992 The Regional policy and strategy designed insure

on are to that source will allowed discharge any wastewater which 1 results instream

no be to in aquatic toxicity 2 causes a violation applicable narrative numerical State water

of an or

quality standard resulting nonconformance with provisions CFR Part

in the of 40 122.44 3 results endangerment a drinking water supply 4 results

d in the of or in aquatic bioaccumulation which threatens human health

3 Implementation

The State Arkansas currently implementing EPA's Post Third Round Policy

of is in conformance with EPA Regional strategy The 5year NPDES permits contain

the

technology based effluent limitations reflecting best controls available Where these

the technology based permit limits protect water quality designated uses

do not or the or where there applicable technology based limits additional water quality based

are no effluent limitations and conditions included NPDES permits State narrative

or are in the and numerical water quality standards from Regulation No 2 used conjunction

the are in

with EPA criteria and other available toxicity information determine adequacy

to the of technology based permit limits and need additional water quality based controls

the for

4 Priority Pollutant Scan

accordance with regional policy ADEQ has reviewed and evaluated effluent

In the the in

evaluating potential toxicity each analyzed pollutant

the of

a The results were evaluated and compared EPA’s Minimum Quantification

to Levels MQLs determine potential presence a respective toxic pollutant

to the of

Those pollutants which greater than equal MQLs determined

are or to the are to

reasonably present effluent and evaluation their potential toxicity

be in the an of is necessary

b Those pollutants with one datum shown nondetect ND providing level

as the detection equal lower than MQL determined not potentially

or of is to are to be

present effluent and eliminated from further evaluation

in the

c Those pollutants with a detectable value even below the MQL are determined

if to

reasonably present effluent and evaluation their potential toxicity

be in the an of is necessary

E NPDES PermitAR0037842 Page 9 Fact Sheet

of Permit No AR0037842

d For those pollutants with multiple data values and values determined

all are to be

nondetect therefore further evaluation necessary However where data

no is set includes some detectable concentrations and some values ND onehalf the

as of

detection level used those values below level detection calculate

is for the of to geometric mean data set

the of the

The concentration each pollutant after mixing with receiving stream was compared

of the applicable water quality standards established the Arkansas Water Quality

to the as in Standards Reg No 2 and with aquatic toxicity human health and drinking water

the criteria obtained from Quality Criteria Water 1986 Gold Book The following

the for expression was used calculate pollutant instream waste concentration IWC

to the

IWC X Qe X Qb Qb

Ce Cb Qe

Where

IWC instream concentration pollutant after mixing with receiving stream

of Fgl pollutant concentration effluent Fgl

Ce in

effluent flow facility cfs

Qe of background concentration pollutant receiving stream Fgl

Cb of in background flow receiving stream cfs

Qb of

The following values were used IWC calculations

in the

varies with pollutant A single value from Priority Pollutant Screen PPS

Ce the submitted permittee part NPDES permit application geometric

by the as of the or the

mean a group data points less than data points multiplied a factor 2.13

of of 20 is by of This factor based EPA's Region procedure See attachment Continuing

is on VI IV of Planning Process CPP extrapolate limited data sets better evaluate potential

to to the

toxicity higher effluent concentrations exceed water quality standards This

for to procedure employs a statistical approach which yields estimate a selected upper

an of

percentile value 95th percentile effluent data which would expected

the of an set be to exceed 95 effluent concentrations a discharge more data points during the

of in If 20 or

last two years available multiply 2.13 instead use maximum

are do not by but the reported values

Outfall 101 9.83 MGD based highest monthly average flow during

Qe on the the last two years

Outfall 401 406.08 MGD based highest monthly average flow

on the during last two years

the

0 _g l

E NPDES PermitAR0037842 Page Fact Sheet

10 of Permit No AR0037842

See below

e Aquatic Toxicity

Chronic Toxicity Flow 0 cfs comparison with chronic aquatic toxicity This flow

for percent 7day 10year low flow 7Q10 receiving stream

is 67 of the for the In the absence information regarding 7Q10 SWEPCO Reservoir 7Q10 zero

of the of of cfs is

used assure that violations metals will occur under most conservative

to no of the the assumptions

Acute Toxicity Flow 0 cfs comparison with acute aquatic toxicity This flow

for is percent 7Q10 receiving stream

33 of the for the

f Bioaccumulation

Flow 4 cfs comparison with bioaccumulation criteria This flow based

for is the on the CPP

g Drinking Water

Flow 0 cfs comparison with drinking water criteria absence information

for In the of regarding 7Q10 SWEPCO Reservoir 7Q10 zero used assure that

the of of cfs is to no

violations metals will occur under most conservative assumptions

of the the

The following values were used determine limits pollutants

to for the

Hardness 148 mgl based attachment CPP

on VI of

7.54 su based compliance data from Arkansas Water Quality Inventory

pH on Report305 b Water Quality Data Base System utilizing ADEQ accumulated data

for Station ARK0004A

5 Water Quality Standards Metals and Cyanide

for

Standards Chromium VI Mercury Selenium and Cyanide expressed a

for are as function pollutant's water effect ratio WER while standards cadmium

of the for chromium III copper lead nickel silver and zinc expressed a function

are as of the pollutant's water effect ratio and a function hardness

as of

The Water effect ratio WER assigned a value unless scientifically defensible

is of 1.0 study clearly demonstrates that a value less than necessary a value greater than

1.0 is or

sufficient fully protect designated uses receiving stream from toxic

1.0 is to the of the the effects pollutant

of the

The WER approach compares bioavailability and toxicity a specific pollutant

of in receiving water and laboratory test water involves running toxicity tests least

in It for at

E NPDES PermitAR0037842 Page Fact Sheet

11 of Permit No AR0037842

two species measuring LC50 pollutant using local receiving water collected

for the the

from site where criterion being implemented and laboratory toxicity testing

the the is

water made comparable water terms chemical hardness The ratio

to the site in of between site water and lab water LC50 used adjust the national acute and chronic

is to

criteria site specific values

6 Conversion Dissolved Metals Criteria for Aquatic Life Total Recoverable

of to Metal

Metals criteria established Regulation No 2 aquatic protection based

in for life are on dissolved metals concentrations and hardness values See Page 6 Attachment 1

of However Federal Regulations cited CFR 122.45 c require that effluent limitations

at 40

metals NPDES permits expressed total recoverable See Pages 1 and 6

for in be as of Attachment 1 Therefore a dissolved total recoverable metal conversion must

to the be

implemented This involves determining a linear partition coefficient metal

for the of

concern and using this coefficient determine fraction metal dissolved that

to the of so the dissolved metal ambient criteria may translated a total effluent limit The formula

be to

converting dissolved metals total recoverable metals streams and Reservoirs

for to for are provided Attachment 2 and Region 6 Implementation Guidance Arkansas Water

in for Quality Standards promulgated CFR 131.36

at 40

7 Comparison submitted information with the water quality standards and

of the criteria

The following pollutants were determined present effluent reported

to be in the as by the permittee

Pollutant Concentration Reported _gl MQL _g l

Outfall 001 Zinc 3.6

Phenols 10 5

Outfall 101 Copper 12

Phenols 10 5

Outfall 401 Copper 19

Phenols 10 5

The following data points have been considered 21_g l application 4 _g l

set of

August 5 2005 4 _gl August 2005 4 l August 2005 Geometric

12 _g 19 mean has been calculated accordance with Continuing Planning Process page D

in the Appendix D

30 of

1 4 X 2 X 2 X 2 3.6 _g l

E NPDES PermitAR0037842 Page Fact Sheet

12 of Permit No AR0037842

Based application

on the

However ADEQ has determined from information submitted permittee that

the by the no water quality standards Gold Book criteria are exceeded Therefore permit action

or no is necessary maintain these standards criteria See Attachment 1

to or

Oklahoma Water Quality Standards Evaluation

Both Outfalls 101 and 401 discharge SWEPCO Reservoir which impoundment

to is an of Little Flint Creek SWEPCO Reservoir a water State Arkansas This Reservoir

is of the of was have a surface area approximately 530 acres with average depth 34.5

to of an of ft The reservoir’s total volume 18,300 It’s drainage area consist 10,500 acres

is ac ft of in

Little Flint watershed There has never been a discharge over reservoir’s

the the uncontrolled concrete spillway structure However 1984 a collection system was

installed near dam accumulate water which had seeped from reservoir

the of the to the toe and pump back into reservoir A daily average release least 2 1.29 mgd

at it the of cfs flow through spillway overflow seepage pumping into Little Flint Creek Outfall

or 001 required permit

is in the

addition tremendous dilution that takes place SWEPCO Reservoir discharge

In to in the

travels approximately 2 miles reach Oklahoma’s state line where further dilution takes

to place

A Effluent Analysis Summary Aquatic Life Protection

for

Outfall 001Little Flint Creek

2.13 WQ Acute WQ Chronic

Ce Pollutant Ce _g l IWC _gl _gl _gl l

Zinc 7.67 7.67 123.48 111.85

3.6

Effluent concentration based Priority Pollutant Scan PPS

Ce on

X 2.13 Reasonable potential factor Referred C95 ODEQ’s CPP

to as in

Instream Waste Concentration IWC IWC Referred C ODEQ’s CPP

to as in is

determined first calculating dilution capacity receiving stream The

by the of the Q value Q will determine which three equations used calculate C

of of is to be to the concentration the mixing zone boundary Following equations were taken from Part

on Chapter 2 page 114 ODEQ’s CPP

III of in

Q Qe 13.91 13.9

Qu maximum flow Outfall 101 9 MGD 13.9 Outfall 001

at Qe at cfs

7Q2 receiving stream assume 0 cfs since 7Q2 available

Qu of not

E NPDES PermitAR0037842 Page Fact Sheet

13 of Permit No AR0037842

Since Q greater than 0.3333 following equation from ODEQ’s CPP will used

is the be determine concentration mixing zone

to the on the

C C95

Based Oklahoma Water Resource Board OWRB proposed 1994 and revised

on 1995 numerical criteria Oklahoma water quality standards OWQS

on for the numerical chronic and acute criteria toxic substances Fish and Wildlife Propagation

for OAC 785455 e6 amended 1997 hardness dependent criteria were

12 G All

calculated using a hardness value 106.55 mgl CaCo3 Segment No 121700

of for as taken from Oklahoma’s Continuing Planning Process CPP2000

seen above table the calculated IWC does not exceed any Oklahoma Water

As in the

Quality Standards Therefore permit limits necessary aquatic life protection

no are for

Phenols have been reported _gl According Oklahoma’s CPP MQL

as 10 to the of 10

_gl has been established method 625 Therefore assumed that there

for it are no is Phenols the effluent Outfall 001

in at

Outfalls 101 and 401

The only parameter determined effluent discharged SWEPCO Reservoir

to be in the to was Copper the Best Engineering Judgment permit writer that evaluation

It of the the is potential this parameter exceed Oklahoma’s Water Quality Standards

of the of to is not

necessary since this parameter not shown present downstream from these

is to be Outfalls Little Flint Creek Outfall 001

B Effluent Analysis Summary Human Health Protection

for

Human Health Pollutant Ce _g l 2.13 _gl IWC _g l Ce Standard l

Zinc 7.67 7.67

3.6

Oklahoma does not have any numerical criteria this parameter

for

Effluent concentration based Priority Pollutant Scan PPS

Ce on

X 2.13 Reasonable potential factor

IWC computed using a mass balance model complete mixing between

is for the

effluent and receiving water The equation follows

the is as

IWC Qlta 2.13 Qlta

Qe Qe Ce Cu

background concentration assumed zero

Cu to be

E NPDES PermitAR0037842 Page Fact Sheet

14 of Permit No AR0037842

maximum average discharge flow 13.9 Outfall 001

Qe cfs

Qlta long term average flow 4

cfs

Based Oklahoma Water Resource Board OWRB proposed 1994 and

on revised 1995 numerical criteria OAC 785 455 e8 on 12 B

For substances which Oklahoma does not have numerical criteria ADEQ

the for has determined that these substances demonstrate reasonable potential

do not under Arkansas criteria Therefore permit action necessary protect human

no is to health

Final Limitations

The following effluent limitations report requirements were placed permit based

or in the on

more stringent technology based water quality based previous NPDES permit

the of the or limitations

Outfall 001

Parameter Water Quality Technology Previous NPDES Final Permit

Based Based Permit

Monthly Daily Monthly Daily Monthly Daily Monthly Daily Avg Max Avg Max Avg Max Avg Max

mgl mgl mgl mgl mgl mgl mgl mg l 6.0 su NA 6 u 6.0 su

pH 9.0 9s 9.0

Outfall 101

Parameter Water Quality Technology Previous NPDES Final Permit

Based Based Permit

Monthly Daily Monthly Daily Monthly Daily Monthly Daily Avg Max Avg Max Avg Max Avg Max

mgl mgl mgl mgl mgl mgl mgl mg l TSS NA NA

25 43 25 43 25 43

OG 6 8 6 8 6 8

10 15

6.0 su su 6 u 6.0 su

9.0 pH 9.0 6.0 9s 9.0

E NPDES PermitAR0037842 Page Fact Sheet

15 of Permit No AR0037842

Outfall 401

Parameter Water Quality Technology Previous NPDES Final Permit

Based Based Permit

Monthly Daily Monthly Daily Monthly Daily Month Daily Avg Max Avg Max Avg Max Max

mgl mgl mgl mgl mgl mgl Avg mg l

mgl TRC NA NA NA 0.2 NA 0.2 NA 0.2

Temperature NA 129.2 F NA NA NA 129.2 F NA 129.2 F

6.0 su su 6 u 6.0 su

9.0 pH 9.0 6.0 9s 9.0

Instantaneous Maximum

Biomonitoring

Section 101 3 the Clean Water Act states that national policy that the

is a of it the discharge toxic pollutants toxic amounts prohibited addition ADEQ required

of in be In is under CFR Part 122.44 d1 adopted reference Regulation 6 include conditions

40 by in to as necessary achieve water quality standards established under Section 303 Clean Water

to as of the

Act Arkansas has established a narrative criteria which states toxic materials shall not

be present receiving waters such quantities toxic human animal plant aquatic

in in as to be to or life interfere with normal propagation growth and survival aquatic biota

to or the of

Whole effluent biomonitoring most direct measure potential toxicity which incorporates

is the of

effects synergism effluent components and receiving stream water quality

the of of characteristics the national policy EPA use bioassays a measure toxicity allow

It of to as of to is evaluation effects a discharge upon a receiving water Federal Register 9016 9019

of the of 49 March 9 1984 EPA Region 6 and State Arkansas now implementing Post Third

the of are the Round Policy and Strategy established September 9 1992 Biomonitoring effluent

on of the is thereby required a condition this permit assess potential toxicity The biomonitoring

as of to procedures stipulated a condition this permit follows

as of are as

TOXICITY TESTS FREQUENCY

Chronic Biomonitoring Once quarter

Requirements measurement frequency based appendix D CPP

for are on of

Since 7Q10 less than 100 sec and dilution ratio less than 1001 chronic

is cfs ft3 is biomonitoring requirements will included permit

be in the

E NPDES PermitAR0037842 Page Fact Sheet

16 of Permit No AR0037842

The Critical Dilution CD 17 Outfall 101 continued from previous permit based

of is the on submitted mixing zone study conducted FTN Associates The Critical Dilution CD

the by of 40 Outfall 401 also continued from previous permit

is the

Toxicity tests shall performed accordance with protocols described Shortterm Methods

be in in Estimating Chronic Toxicity Effluents and Receiving Waters Freshwater

for the of to Organisms EPA600 4 002 July 1994 A minimum five effluent dilutions addition

91 of in to

appropriate control used toxicity tests These additional effluent

an 0 are to be in the concentrations Outfall 101 10 13 17 and 23 and the Outfall 401

for the are 7 for 17 23 30 40 and 54 See Attachment I CPP The low flow effluent

are of concentration critical dilution defined 17 effluent Outfall 101 and 40 effluent

is as for the Outfall 401 The requirement chronic biomonitoring tests based magnitude

for the for is on the of

facility's discharge with respect receiving stream flow The stipulated test species

the to Ceriodaphnia dubia and Fathead Minnow Pimephales promelas are indigenous the

the to geographic area facility use these consistent with requirements State

of the the of is the of the water quality standards The biomonitoring frequency been established provide data

has to representative toxic potential facility's discharge accordance with regulations

of the of the in the promulgated CFR Part 122.48

at 40

Results dilutions well associated chemical monitoring pH temperature

of all as as the of hardness dissolved oxygen conductivity and alkalinity shall reported according

be to EPA600 491 002 July 1994 and shall submitted attachment Discharge

be as an to the Monitoring Report DMR

This permit may reopened require further biomonitoring studies Toxicity Reduction

be to Evaluation TRE and effluent limits biomonitoring data submitted Department shows

or if to the toxicity permittee's discharge Modification revocation this permit subject

in the or of is to the provisions CFR 122.62 adopted reference ADEQ Regulation No 6 Increased

of 40 as by in or intensified toxicity testing may also required accordance with Section 308 Clean

be in of the Water Act and Section 84201 Arkansas Water and Air Pollution Control Act Act 472

of the of 1949 amended

Administrative Records

The following information summarized toxicity test submitted permittee during term

by the the current permit outfalls 101 and 401 See Attachment 4

of the at

Sample Type and Sampling Frequency

Regulations promulgated CFR 122.44 i l require permit establish monitoring

at 40 to requirements which assure compliance with permit limitations

Requirements sample type and sampling frequency have been based current

for on the NPDES permit

E NPDES PermitAR0037842 Page Fact Sheet

17 of Permit No AR0037842

Changes from the previously issued permit

a The name permittee has been corrected

of the b The coordinates the facility and Outfalls have been corrected

of all c A detailed description facility location has been corrected Sections

of d A requirement monitoring and reporting Sulfates has been deleted

for for e The effluent limitations have been changed from 69 su 6.0 su

for pH to 9.0

f The internal Outfall 301 has been eliminated g Part Part III and Part have been revised

II IV h Reporting requirements biomonitoring Outfalls 101 and 401 have changed Part IA

for at

i Requirements compliance with CFR Part 125 Subpart J have been added Part

for 40 to III

SCHEDULE OF COMPLIANCE

Compliance with final effluent limitations required following schedule

is by the

Compliance required effective date permit

is on the of the

The permittee shall comply with the Cooling Water Intake regulations found Title Code

in 40 Federal Regulations Part 125 Subpart J These regulations include limited

are of but not to following provisions

the

a The permittee shall submit two copies Proposal Information Collection

of the for to the

NPDES Branch Water Division prior start information collection

of the to the of activities and

b The permittee shall submit two copies completed Comprehensive Demonstration

of the Study NPDES Branch Water Division prior January 7 2008

to the of the to or on or

before federal deadline that EPA may reestablish complying with

the the for the requirements CFR 125 Subpart J The permittee shall meet other applicable

of 40 all requirements this regulation

MONITORING AND REPORTING

The applicant times required monitor discharge a regular basis and report

is at all to the on results monthly The monitoring results will available public

the be to the

SOURCES

The following sources were used draft final permit

to the

A NPDES application No AR0037842 received 2005

04 29 B Arkansas Water Quality Management Plan WQMP C Regulation No 2 D Regulation No 6 E CFRs 122 125 423

E NPDES PermitAR0037842 Page Fact Sheet

18 of Permit No AR0037842

F NPDES permit file AR0037842 G Discharge Monitoring Reports DMRs H Identification and Classification Perennial Streams Arkansas Arkansas

of of Geological Commission I Continuing Planning Process CPP

J Technical Support Document For Water Quality based Toxic Control K Region 6 Implementation Guidance Arkansas Water Quality Standards promulgated

for CFR 131.36

at 40 L Email dated November 2 2005 from Clem Jastrzebski

to M Email dated August 2005 from Steward Jastrzebski

31 to N Site visit July 2005

on 21 O Letters dated June 9 2005 July 2005 July 2005 August 2 2005 from David C

25 27 Bouchard Jastrzebski

to P Oklahoma Department Environmental Quality Continuing Planning Process 2002

of Edition

Q Oklahoma’s Water Quality Standards R Letter dated December 2005 from Russell W Draves Manager AEP Water and

22 Ecological Resource Services ADEQ

to S Email dated January 2005 from David C Bouchard DVM MPH

10 AEP Water and Ecological Resource Services Jastrzebski

E NPDES PermitAR0037842 ENPDES Permit AR0037842 Attachment 1

PPS

E NPDES PermitAR0037842 Attachment 2

Linear Partition Coefficients for Priority Metals Streams and Reservoirs

STREAMS RESERVOIRS METAL

Kpo a Kpo a

Arsenic 0.48 X 0.73 0.48 X 0.73

106 106

Cadmium 4.00 X 1.13 3.52 X 0.92

106 106

Chromium 3.36 X 0.93 2.17 X 0.27

106 106

Copper 1.04 X 0.74 2.85 X

106 106 0.9

Lead 2.80 X 2.04 X 0.53

106 0.8 106

Mercury 2.90 X 1.14 1.97 X 1.17

106 106

Nickel 0.49 X 0.57 2.21 X 0.76

106 106

Silver 2.40 X 1.03 2.40 X 1.03

106 106

Zinc 1.25 X 0.7 3.34 X 0.68

106 106

Kpo X TSSa

Linear Partition Coefficient

Kp TSS Total Suspended Solids mgl See Attachment 3 Kpo found from table

a found from table

C 11 X TSS X 6 C Fraction Metal Dissolved

Ct Kp 10 Ct of

Delos C G W L Richardson J V DePinto R B Ambrose P W Rogers K Rygwelski J P John W J Shaughnessey T A Faha W N Christie Technical

St Guidance Performing Waste Load Allocations Book Streams and Rivers Chapter

for II 3Toxic Substances U S Environmental Protection Agency EPA 440 484022

for the

Linear partition coefficient shall apply Chromium numerical

not to the VI

criterion The approved analytical method Chromium measures only dissolved

for VI the

form Therefore permit limits Chromium shall expressed dissolved form

for VI be in the See CFR 122.45 c3

Reference page EPA memo dated March 3 1992 from Margaret J

18 of Stasikowski WH 586 Water management Division Directors Region I

to IX

Texas Environmental Advisory Council 1994

E NPDES PermitAR0037842 Attachment 3

TOTAL SUSPENDED SOLIDS 15th PERCENTILE BY RECEIVING STREAM AND ECOREGION

For direct discharges Arkansas Red Ouachita White and Francis Rivers use

to the St the following mean values

TSS15th percentile

Receiving Stream TSS Unit

Arkansas River

Smith Dardanelle Dam 12.0 mgl

Ft to Dardanelle Dam Terry D 10.5 mgl

to L Terry D D 5 mgl

L to L 8.3 L D 5 Mouth mgl

to 9.0

Red River mgl

Ouachita River

above Caddo River 2.0 mgl

below Caddo River 5.5 mgl White River

above Beaver Reservoir mgl

2.5 Bull Shoals Black River 3.3 mgl

to Black River Mouth 18.5 mgl

Francis River mgl

St 18

For other discharges following ecoregion TSS

all use the

TSS 15th percentile

Ecoregion TSS Unit

Ouachita 2 mgl

Gulf Coastal 5.5 mgl

Delta 8 mgl

Ozark Highlands mgl

2.5

Boston Mountains mgl

1.3

Arkansas River Valley 3 mgl

E NPDES PermitAR0037842 RESPONSE TO COMMENTS FINAL PERMIT DECISION

This our response comments received subject draft permit accordance with

is to on the in regulations promulgated CFR Part 124.17

at 40

Permit No AR0037842

Applicant American Electric Power

Southwestern Electric Power Company Flint Creek Power Plant

Prepared Marysia Jastrzebski PE

Permit Action Final permit decision and response comments received draft

to on the permit publicly noticed December 2005

on 09

Date Prepared January 2006

The following comments have been received draft permit

on the

Letter from Russell W Draves Manager AEP Water and Ecological Resource Services

to ADEQ dated December 2005

I Response issues raised

ISSUE 1

“Cover Letter Public Notice Page 1 Fact Sheet and Page 1 the Draft Permit

of the of

Address – underlined parts following indicate corrected address

the in the the

Southwestern Electric Power Company –Flint Creek Power Plant”

RESPONSE 1

The Department agrees The requested corrections have been made

ISSUE 2

“Page 2 Fact Sheet 6 Receiving Stream Segment …

The line leading into outfalls should say

the list of

“The outfalls located following coordinates:””

is are at the

E NPDES PermitAR0037842 RESPONSE 2

The Department agrees The requested correction been made

has

ISSUE 3

“ Page 2 Fact Sheet 7 Parentheses Parentheses used Act designate paragraph

are in the to the

“ 7 303 d List and Endangered Species Considerations,” and

“A 303d List,” and

“The receiving stream listed 303 d list.”

is not on the

RESPONSE 3

The Department agrees The requested revision has been made

ISSUE 4

“Page s 5 and Fact Sheet Temperature – Inst Max

16 The reference Inst Max inadvertently applied temperature was intended only

to is to It total residual chlorine Daily Max should appear temperature box page 5

for in the on with 129.2oF instead Inst Max See Page 3 Part where Daily Maximum

of of IA Temperature footnoted should have been i e “…Daily maximum temperature

is as it

shall highest flow weighted average temperature calculated month.”

be the for the

RESPONSE 4

The Department agrees The requested revision has been made without word

the

“average”

ISSUE 5

“Page 6 Fact Sheet TSS and OG The Fact Sheet states that these parameters have been based current NPDES

on the permit and CFR 122.44 1 –should this CFR 122.44 a

40 be 40 1 This a belongs also missing Page 8 the Fact Sheet

if is on of it

Though draft and current permits have same limits could ask that Fact

the do the we the Sheet briefly address why these limits different than categorical limits found

are the in 40 CFR 423.12 b3 and CFR 423b4

The permit limits total residual chlorine are same the CFR categorical limits

for the as

This why unclear how this difference between permit and CFR

is it to us the the is concentrations TSS and OG were derived.”

for

E NPDES PermitAR0037842 RESPONSE 5

The Department agrees The final Fact Sheet Section B2 Pages 5 and 6 has been

12 on

revised briefly address this issue

ISSUE 6

“ Page Fact Sheet 7 Comparison…

12 request permit writer zinc Zn was retested three consecutive weeks

At the of the for at

Outfall 001 establish whether elevated concentration reported the first

to or not Zn in the analysis was representative These analyses consistently demonstrated concentrations below MQL 4 _gL This should mentioned Fact Sheet instead

the be in the of 21 L least along with

at _g or it.”

RESPONSE 6

The Department agrees The additional three data points have been considered and Zinc concentrations have been recalculated Paragraph 7 Section D and pages

13 of 12 12 Oklahoma’s Water Quality Standards Evaluation have been revised

ISSUE 7

“Page Fact Sheet –Mid paragraph

13 “However 1980 a collection system….”

in should say

“However 1984 a collection system….”

RESPONSE 7

The Department agrees The requested correction been made Page

has on 12

ISSUE 8

“Page Fact Sheet

asterisk appears Daily Maximum Temperature box Water Quality Based

An in the of the Previous NPDES Permit and Draft Permit columns and refers Instantaneous

to Maximum This condition should removed from temperature belongs only with

be as it

total residual chlorine.”

RESPONSE 8

The Department agrees The requested correction has been made Page

on 15

E NPDES PermitAR0037842 ISSUE 9

“Cover Letter

The line leading into list outfalls should say

the of

“The outfalls located following coordinates:”

is are at the

RESPONSE 9

The Department agrees The requested correction has been made cover page the

to the of

final permit

ISSUE

“Page 2 Part IA Outfall 101

of The Gentry POTW discharge included Outfall 101 wastewaters We

is in the list of

believe that presence should included a footnote this page rather than with

its be as on the waste streams actually generated plant should also noted that power

by the It be the plant responsible quantity quality POTW waste stream Please

is not for the or the of the consider this footnote

“The City Gentry discharges treated municipal effluent subject limitations

of to the of its NPDES Permit No AR0020184 into Flint Creek Power Plant’s primary ash pond Flint

Creek Power Plant bears responsibility quality City Gentry’s effluent

no for the of the of any treatment that effluent.”

or for of

RESPONSE

The Department agrees The requested footnote has been added Page 2 Part

on of IA

ISSUE

“Page 2 Part IA Outfall 101 Chronic Biomonitoring

of There five code lines beneath each test species These same codes appear

are in the biomonitoring section Pages 8 and 9 Part with items E and F reversed

of III in positions

For consistency these lists should same order both sections permit

be in the in of the

RESPONSE

The Department agrees Pages 8 Part have been revised

of III

E NPDES PermitAR0037842 ISSUE

“Page 2 Part IA Outfall 101 Sampling Point

of We believe would clearer especially inspector who familiarwith

it be to an is not as the plant and plant site make the following change regarding sampling point

to the

“Samples taken compliance with monitoring requirements specified above shall

in the be taken discharge from final treatment unit secondary ash pond

at the the

or “Samples taken compliance with the monitoring requirements specified above shall

in be

taken discharge from final treatment unit secondary ash pond the final

at the the

treatment unit).”

RESPONSE

The Department agrees Page 2 Part has been revised

of IA

ISSUE

“Page 3 Permit Part IA Outfall 401 Temperature

of The temperature parameter requires Daily Maximum Average Temperature

the to be reported and does this page The Instantaneous Maximum does not appear here

so on as

Fact Sheet which correct A definition ‘ Instantaneous Maximum’

it did in the is of in Part IV Definitions would also helpful.”

RESPONSE

The Department concurs regard calculation temperature A definition has been

in to of included page 3 Part “Daily maximum temperature shall highest daily

on of IA be the flow weighted temperature calculated month” sufficient Additionally a

for the is

definition “Instantaneous Maximum” has been added Part permit

of in IV of the

ISSUE

“Page 3 Permit Part IA Temperature –Footnote 4

second sentence this footnote ‘ daily’ and ‘ average’ have been omitted

In the of should read

“Daily maximum temperature shall highest daily flow weighted average

be the temperature calculated month.”

for the

RESPONSE

The Department agrees Page 3 Part has been revised add the above language

of IA to without word “average”

the

E NPDES PermitAR0037842 ISSUE

“Page 3 Permit Part IA Chronic Biomonitoring

of There are five code lines beneath each test species These same codes appear the

in biomonitoring section Pages 8 and 9 Part with items E and F reversed

of III in positions

RESPONSE

The Department agrees Page 8 Part been revised

of III has

ISSUE

Page 3 Part 8 Property Rights

of II There a repeated phrase

“The issuance this permit does not convey any property rights any sort any

of of or

property rights any sort any exclusive….”

of or

RESPONSE

The Department agrees Part 8 been corrected

II has

ISSUE

“Page 4 Part 5 Upset Conditions second line the page should say

of II on

“…noncompliance with such technology based permit….”

RESPONSE

The Department agrees Part 5 a has been corrected

ISSUE

“Page 8 Part 1 Planned Changes For Industrial Dischargers b First line

of II of paragraph

the

“The alternation alteration addition could significantly change nature increase

or the or quality quantity ….”

the of

RESPONSE

The Department agrees Page 8 Part D 1 b has been corrected

of II

E NPDES PermitAR0037842 ISSUE

“Page 3 Part III 2 Persistent Lethality

There simply needs a space between ‘ LETHALITY’ and ‘ The.’

to be

RESPONSE

The Department agrees Page 3 Part 2 has been corrected

of III

ISSUE

“Page 8 Part III 4 c

of “The permittee shall submit results each valid toxicity test a DMR….”

the of on

RESPONSE

The Department agrees Part III 4 c has been corrected

ISSUE

“Page 89 Part III 4 REPORTING c i and

of ii This the code order that arranged differently than the outfall pages”

is is on the

RESPONSE

The Department agrees Part 4 c has been corrected

III

ISSUE

“ Page Part III 5 Storm Water Pollution Plans

13 of We believe following revision would shorten and sharpen this paragraph without

the changing meaning

its

Storm Wwater Pollution Plans 5 Storm water runoff commingling with other process wastewater discharged from Outfall

101 shall managed accordance with Best Managmenet Management Practices

be in the BMPs form a pollution prevention plan SWPPP required Arkansas

in the of by the Industrial General Storm Water Permit ARR000000 control quality storm water

to the of

discharges associated with industrial activity that authorized under CFR

are 40 122.44 when Permitting Authority finds numerical effluent limitations

k the to be

infeasible carry purposes Clean Water Act.”

to out of the the

RESPONSE

The Department agrees Part III 5 has been revised

E NPDES PermitAR0037842 ISSUE

“Page Part III 6 PCB

13 of

There shall discharge polychlorinated biphenyl transformer fluid.”

be no of

RESPONSE

The Department agrees Part 6 has been corrected

III

ISSUE

“Page Part III 7 Total Residual Chlorine

13 of Page 1 Part Condition 3 Other Specified Monitoring Requirements states

On of III it that with ADEQ approval alternative monitoring methods may used other than those

be specified Part I Section A Part I Section A refers Page Part Other

in At it to 13 of III Condition 7 which gives specifics related total residual chlorine connect these

the to To

three references suggest inserting following paragraph second paragraph

we the as the of Condition 7 Page Part

on 13 of III

“The permittee may use alternative appropriate monitoring methods and analytical

instruments other than specified Part I Section A the permit without a major

as in of permit modification complying with the procedure found Page 1 Part III

by on of Condition 3 Other Specified Monitoring Requirements.”

RESPONSE

The Department agrees This language already included Condition 3 Part III

is in of

ISSUE

“Page Part III b

14 of 12 The current federal deadline submitting study required CFR 125j 316b

for the by 40 given deadline this draft permit this deadline may changed think

is as the in As be we following qualification should included Paragraph b this condition

the be in of

“The permittee shall submit two copies completed Comprehensive Demonstration

of the Study the Enforcement Section NPDES Branch Water Division prior

to of of the to January 7 2008 before federal deadline that EPA mayreestablish

or on or the the for

complying with requirements CFR 125 Subpart J).”

the of 40

RESPONSE

The Department agrees The requested language has been added Condition 12 b

to of Part and Page 1 Part 1B Schedule Compliance

III to of of

E NPDES PermitAR0037842 E NPDES PermitAR0037842 E NPDES PermitAR0037842 E NPDES PermitAR0037842

Hydraulic Analysis Flint Creek Power

of Plant Ash Ponds

American Electric Power Company

Prepared by

FREESE AND NICHOLS INC 4055 International Plaza Suite 200 Fort Worth Texas 76109 817_735_ 7300

AEP10431 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

Prepared by

FREESE AND NICHOLS INC

4055 International Plaza Suite 200 Fort Worth Texas 76109 817_735_ 7300

AEP10431 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

TABLE OF CONTENTS

1.0 Introduction 1

2.0 Hydrologic Model Development 3

Basin Delineation Connectivity 3

2.1

Hydrologic Parameters 5

2.2

Elevation_ Storage Data 8

2.3

Discharge Rating 9 2.4 Curves Frequency Model Results

2.5

PMF Model Results

2.6

3.0 Summary and Conclusions

LIST TABLES

OF Table 1 –Curve Number Calculation Matrix5 Table 2 –Basin Parameters 8

Table 3 –Elevation_ Storage Data 9

Table 4 –Discharge Rating Curves

Table 5 –Frequency Precipitation Depths

Table 6 –Frequency Model Results

Table 7 –HMR_ Point Rainfall Depths

52 14

Table 8 –PMF Model Results

Table 9 –Pertinent Dam Information

Table –Summary Results

10 of 16

LIST FIGURES

Figure 1 –Location Map 2

Figure 2 –Drainage Basin Map 4

Figure 3 –Hydrologic Soil Classifications 6

Figure 4 –Land Cover Data 7

Figure 5 –Primary Ash Pond Spillway

Figure 6 –Secondary Ash Pond Spillway

Figure 7 –PMP Rainfall Hyetograph

APPENDICES

Appendix A –References

Appendix B –Discharge Rating Curve Calculations and Hydrologic Parameters

Appendix C –Pertinent Drawings

January 2011 i Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

INTRODUCTION

1.0

November 2010 Freese and Nichols Inc FNI was retained American Electric

In of by

Power AEP perform various hydrologic and hydraulic calculations determine the

to to hydraulic adequacy the Primary Ash and Secondary Ash Ponds for the Flint Creek Power Plant

of located near Gentry Arkansas This report summarizesthe results the analysis for the 10_

of year 25_year 100_year 25 PMF 50 PMF and 100 PMF events

The two Ash Ponds are situated immediately south the Flint Creek Power Plant on the

of east side Little Flint Creek Reservoir The general location the power plant and associated

of of reservoirs shown Figure 1

is in

January 2011 1 Flint Creek Power Plant

FN PROJECT NO AEP10431 0 1.25 2.5 5 FILE NAME H WR DESIGN FIGURES Miles FIGURE Figure1 LocationMap mxd

DATUM COORDINATE SYSTEM

NAD83 STATE PLANE ARKANSAS NORTH FT 4055 International Plaza Suite 200 FLINT CREEK POWER PLANT ASH PONDS p 1 DATE CREATED Fort Worth TX 76109 4895

DECEMBER 2010 817 735 7300

PREPARED BY LOCATION MAP JPM Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

HYDROLOGIC MODEL DEVELOPMENT

2.0

BASIN DELINEATION CONNECTIVITY

2.1

The hydrologic model for the Flint Creek Power Plant Ash Ponds was created

and consisted two total drainage basins shown Figure 2 The total drainage area HECHMS1of as in modeled approximately 1.82 square miles 1,167 acres One basin represents the total area

is or that drains directly into the Primary Ash Pond and the other represents the area that drains only the Secondary Ash Pond The basins were delineated from the National Elevation

Dataset NED 10_meter resolution Digital Elevation Model DEM

The Primary Ash Pond connected the Secondary Ash Pond via a wide open channel

is to controlled a currently silted over concrete and a small weir box a slightly lower

by sill at elevation Discharges from the Secondary Ash Pond flow into Little Flint Creek Reservoir through a similar structure The concrete sill however visible and the weir box has recently

is been replaced Spillway capacities are discussed further detail Section 2.4

in in

Both the Flint Creek Power Plant and the City Gentry Wastewater Treatment Plant

of discharge directly into the Primary Ash Pond Discharges from the power plant consist low

of volume wastewater and stormwater Based data from AEP these discharges were assumed

on constant a flow rate 8.08 MGD 12.5 cfs

at of or

January 2011 3 UV12

Primary 1127 acres

Primary Ash Pond

Secondary Ash Pond

Secondary

UV59 acres

FN PROJECT NO AEP10431 0 1,000 2,000 4,000 FILE NAME H WR DESIGN FIGURES Feet FIGURE Figure2 Basins mxd

DATUM COORDINATE SYSTEM

NAD83 STATE PLANE ARKANSAS NORTH FT 4055 International Plaza Suite 200 FLINT CREEK POWER PLANT ASH PONDS p 2 DATE CREATED Fort Worth TX 76109 4895

DECEMBER 2010 817 735 7300

PREPARED BY DRAINAGE BASIN MAP JPM Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

HYDROLOGIC PARAMETERS

2.2

The HEC_HMS model incorporates the NRCS Curve Number and Unit Hydrograph methods each basin this model the curve numbers were based hydrologic soil

for In on classifications and land cover The instantaneous runoff effect open water surfaces was

of accounted for the development the curve numbers The soils dataset was obtained from

in of the NRCS Soil Survey Geographic Database2 SSURGO and land use dataset was obtained from the USGS Seamless Data Warehouse3 the form the National Land Cover Dataset NLCD for

in of

2001 Spatial information about soil types and land use classifications presented Figures 3

is in and 4 respectively Table 1 provides the matrix used determining the curve number each

in for basin The curve numbers shown Table 1 are for Antecedent Moisture Condition AMC

in II

These values were incorporated the model for the frequency storm events such the 100_

in as year storm event and the PMP event Typically a higher curve number would used

be to simulate a worst_case scenario with the ground fully saturated However because the long

of duration the PMP event and the timing the rainfall distribution the ground will fully

of of be saturated prior the peak the storm and a higher curve number will have significant

to of no impact the results

Table 1 –Curve Number Calculation Matrix

NLCD Classification Curve Number AMC

Description AB BC C CDD

Open Water 100 100 100 100 100 100

Developed Open Space

89 86 88 83 21 68 79

Developed Low Intensity

22 51 68 74 79 82 84

Developed Medium Intensity

77 85 88 90 23 91 92

Developed High Intensity

89 92 93 94 24 95 95

Barren Land

77 86 89 91 31 93 94

Deciduous Forest

36 60 67 73 41 76 79

Evergreen Forest

79 73 76 67 42 36 60

Mixed Forest

43 36 60 67 73 76 79

Scrub Shrub

35 56 63 70 52 74 77

Grassland Herbaceous

39 61 68 74 71 77 80

Pasture Hay

39 61 68 74 81 77 80

Cultivated Crops

67 78 82 85 82 87 89

Woody Wetlands

83 77 80 72 90 45 66

January 2011 5 Primary 1127 acres

Secondary acres

Legend

Basins

Soils

Water

FN PROJECT NO AEP10431 0 1,000 2,000 4,000 FILE NAME H WR DESIGN FIGURES Feet FIGURE Figure3 Soilsmxd

DATUM COORDINATE SYSTEM

NAD83 STATE PLANE ARKANSAS NORTH FT 4055 International Plaza Suite 200 FLINT CREEK POWER PLANT ASH PONDS p 3 DATE CREATED Fort Worth TX 76109 4895

DECEMBER 2010 817 735 7300

PREPARED BY HYDROLOGIC SOIL CLASSIFICATIONS JPM Primary Legend 1127 acres

Basins

LandUse

Secondary 23 acres

FN PROJECT NO AEP10431 0 1,000 2,000 4,000 FILE NAME H WR DESIGN FIGURES Feet Figure4 LandCover mxd FIGURE

DATUM COORDINATE SYSTEM

NAD83 STATE PLANE ARKANSAS NORTH FT 4055 International Plaza Suite 200 FLINT CREEK POWER PLANT ASH PONDS p 4 DATE CREATED Fort Worth TX 76109 4895

DECEMBER 2010 817 735 7300

PREPARED BY LAND COVER DATA JPM Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

The only input into HEC_ HMS for the NRCS Dimensionless Unit Hydrograph a lag time

is which calculated based on basin conditions such hydraulic length and average slope

is as according the NRCS TR_ Method Table 2 provides a summary the hydrologic

to 55 of parameters for each basin

Table 2 –Basin Parameters

Curve Area Lag Time Basin Number mi2 min AMC

Primary 1.76 46.58 76.6

Secondary 0.06 10.53 74.9

ELEVATION STORAGE DATA

2.3

Elevation_ storage data for each reservoir was obtained from a combination two data

of sources Volume calculations based on foot contours were provided AEP up elevation

5_ by to

1145.0 msl The NED 10_meter DEM was utilized calculate the available storage between

ft_ to this elevation and the top dam elevation 1155.0 msl These relationships were used

of of ft_ in the hydrologic model for routing both frequency storm events and the PMF and are shown

Table 3 below

January 2011 8 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

Table 3 –ElevationStorage Data

Primary Secondary

Elevation Storage Elevation Storage

msl acre_ msl acre_

ft_ ft ft_ ft

1115 0.00 1130 0.00

1120 4.59 1135 2.71

1125 23.05 1140 7.39

1130 50.92 1142.5 10.79

1135 86.32 1143 11.47

1140 133.10 1144 12.83

1144 182.55 1145 14.19

1145 186.13 1146 20.54

1146 190.47 1147 26.88

1147 195.62 1148 33.23

1148 201.66 1149 39.58

1149 208.67 1150 45.93

1150 222.59 1151 55.13

1151 263.45 1152 64.71

1152 312.36 1153 74.71

1153 363.73 1154 85.10

1154 417.40 1155 95.92

1155 473.32

DISCHARGE RATING CURVES

2.4

Each dam has a single spillway structure with two components – a weir box acting the

as principal spillway and a concrete acting the emergency spillway Information regarding

sill as the dimensions and elevations each these spillways was taken from a combination

of of of original construction drawings and detailed descriptions from AEP personnel Detailed calculations for the discharge rating curves each spillway are included Appendix B

of in

The principal spillway for the PrimaryAsh Pond consists a weir box with a foot wide

of 4_ weir with crest elevation 1144.0 msl The weir equation used for this weir box was

of ft_ provided AEP personnel elevation 1146.0 msl flow reaches the 228_foot long concrete

by At ft_

sill effectively the emergency spillway and the weir box assumed submerged meaning

is to be flow completely controlled the emergency spillway The located relatively close

is by sill is to the flat natural grade and currently covered with soil and light vegetation due silting over

is to the years such the emergency spillway modeled a broad_ crested weir and the

As is as

January 2011 9 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

discharge rating curve was developed with a steady_ state HEC_ RAS4 model The HEC_RAS model

accounts for submergence the tailwater from the downstream lake which will significantly

of restrict flow through the spillway The discharge rating curve for the combined spillway the

PrimaryAsh Pond shown Table 4 A photograph the spillway shown Figure 5

is in of is in

Figure 5 –PrimaryAsh Pond Spillway

The principal spillway for the Secondary Ash Pond consists a recently reconstructed

of weir box with a 13_foot wide weir with crest elevation 1142.5 msl Calculations several

of ft_ at critical discharges were given the construction drawings for this modification These values

on were interpolated between obtain a discharge rating curve even one_ foot increments

to at At elevation 1145.0 msl flow reaches the 250_foot long concrete sill effectively the emergency

ft_ spillway and the weir box assumed submerged meaning flow completely controlled

is to be is

the emergency spillway While the concrete more defined than the one the Primary

by sill is at

Ash Pond the effects submergence were still a concern due the flat topography and Little

of to

Flint Creek Reservoir immediately downstream Similar the Primary Ash Pond spillway this

to spillway was modeled HEC_ RAS The discharge rating curve for the combined spillway the

in of

Secondary Ash Pond shown Table 4 A photograph the spillway shown Figure 6

is in of is in

January 2011

10 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

Figure 6 –Secondary Ash Pond Spillway

Table 4 –Discharge Rating Curves

Primary Secondary

Total Total Elevation Elevation Discharge Discharge msl msl ft_ cfs ft_ cfs

1144 0 1142.5 0

1145 13 1143 17

1146 1144

34 78

1147 305 1145 165

1148 1,071 1146 536

1149 2,208 1147 1,355

1150 3,603 1148 2,419

1151 5,133 1149 3,735

1152 6,873 1150 5,310

1153 8,816 1151 7,118

1154 10,978 1152 9,174

1155 13,325 1153 11,463

1154 13,974

1155 16,484

January 2011

11 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

FREQUENCY MODEL RESULTS

2.5

Three frequency storm events were analyzed for the Flint Creek Ash Pond system – the

10_ year 25_year and 100_year storm events The hydrologic model described the preceding

in sections was implemented analyzing these events Curve numbers were set Antecedent

in to

Moisture Condition and initial abstractions were calculated automatically HEC_ HMS These

II by assumptions represent normal conditions would expected prior one these storm

as be to of events The precipitation data was obtained from the National Oceanic and Atmospheric

Administration’s Technical Memorandum NWS HYDRO_ 355 and Technical Paper 40.6 These values are presented Table 5 Each storm event was assumed have a duration hours

in to of 24

Table 5 –Frequency Precipitation Depths

Precipitation

Frequency in

yrs 5 min min min 2 3 6 24hr

15 60 hr hr hr 12 hr

1 0.38 0.82 1.53 1.87 2.06 2.32 2.82 3.30

2 0.46 0.98 1.78 2.24 2.39 2.75 3.53 4.11

5 0.54 1.16 2.29 2.83 3.17 3.71 4.03 5.22

0.61 1.30 2.67 3.24 3.58 4.38 5.23 6.08

0.70 1.50 3.09 3.73 4.14 5.08 6.08 7.10

0.78 1.66 3.48 4.20 4.62 5.62 6.78 7.91

100 0.85 1.82 3.86 4.68 5.19 6.21 7.45 8.79

500 1.10 2.35 4.99 6.05 6.71 8.03 9.64 11.37

These precipitation depths serve input data into the hydrologic model and were

as routed through the model described previously According standard engineering practice

as to flood routings were started the lowest spillway crest elevation for each dam This

at corresponds elevation 1144.0 msl and 1142.5 msl for the Primary and Secondary Ash

to ft_ ft_

Ponds respectively The results the 10_ year 25_year and 100_ year storm events are shown

Table 6

January 2011

12 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

Table 6 –Frequency Model Results

Peak Peak Peak

Elevation Inflow Outflow

msl cfs cfs

ft_

10_ Year Storm Results

Primary 1148.55 1718.09 1700.04

Secondary 1147.33 1721.99 1706.83

25_ Year Storm Results

Primary 1148.94 2169.32 2149.13

Secondary 1147.75 2175.62 2156.64

100_ Year Storm Results

Primary 1149.48 2933.96 2862.69

Secondary 1148.35 2893.87 2874.07

PMF MODEL RESULTS

2.6

The Probable Maximum Flood PMF defined the greatest flood expected and

is as to be the Probable Maximum Precipitation PMP theoretically the greatest depth rainfall for a

is of given duration that physically possible over a given size storm area a particular geographic

is at location Generally the rainfall depth calculated for the ten square miles the watershed

is of which receive the highest intensity rainfall

7 Hydrometeorological Report No HMR_ 52 developed the US Army Corps

52 by of

Engineers was used determine the rainfall for each basin PMP estimates were taken from

Hydrometeorological Report No 518 and distributed according HMR_ obtain average

to 52 to rainfall depths over the various drainage areas

HMR_ calculates rainfall depths for storm durations ranging from five minutes

52 to

seventy_ two hours Table 7 lists the point rainfall depths calculated HMR_ storm

by 52 for durations from one hour hours Because the total drainage area less than ten square

to 72 is miles the same rainfall depths were applied both basinsHMR_ also produces a 72_ hour

to 52 critically stacked temporal distribution arranging the incremental rainfall depths produce

by to the rainfall hyetograph shown Figure 7

January 2011

13 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

Table 7 –HMR52 Point Rainfall Depths

Storm Depth Duration

hr in

1 15.89

2 19.98

3 23.22

6 29.14

12 34.10

38.61

48 42.92

45.40

1.8

1.6

1.4

in 1.2

Depth

0.8

Rainfall

0.6

0.4

0.2

0 12 24 36 48 60 72

00 00 00 00 00 00 00

Time hrs

Figure 7 –PMP Rainfall Hyetograph

January 2011

14 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

The PMF was modeled described previously with flood routing started the lowest

as at spillway crest elevation –1144.0 msl and 1142.5 msl for the Primary and Secondary Ash

ft_ ft_

Ponds respectively Additionally the 25 and 50 PMF were calculated for the two Ponds

Table 8 contains the results these PMF model runs –the 25 PMF 50 PMF and 100 PMF

of respectively

Table 8 –PMF Model Results

Peak Peak Peak

Elevation Inflow Outflow

msl cfs cfs

ft_

25 PMF Results

Primary 1150.04 3757.22 3627.15

Secondary 1148.94 3670.68 3660.88

50 PMF Results

Primary 1151.96 7501.95 6713.03

Secondary 1150.80 6787.60 6764.12

100 PMF Results

Primary 1154.87 14991.39 12803.89

Secondary 1153.45 13008.71 12600.25

January 2011

15 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

SUMMARY AND CONCLUSIONS

3.0

Based the results the hydraulic analysis both dams are hydraulically adequate for

on of the full range storm events from the 10_ year the 100 PMF event Table 9 lists the

of to pertinent elevation data for each dam including the top dam elevation and principal and

of emergency spillway crest elevations Comparing these elevations the maximum water

to surface elevations shown Table indicates that each dam would safely contain flood

in 10 all events and including the 100 PMF Additionally the emergency spillway for both dams

up to

engaged somewhat frequently even during a storm event low the 10_ year storm This

is as as should have adverse affects these structures they appear designed withstand

no on as to be to frequent engaging

Table 9 –Pertinent Dam Information

Top Principal Emergency

of Dam Spillway Spillway msl msl msl

ft_ ft_ ft_

Primary 1155.00 1144.00 1146.00

Secondary 1155.00 1142.50 1145.00

Table 10 –Summary Results

of 25 50 100 10_ year 25_year 100_ year PMF PMF PMF

Primary 1148.55 1148.94 1149.48 1150.04 1151.96 1154.87

Secondary 1147.33 1147.75 1148.35 1148.94 1150.80 1153.45

should noted that these results reflect the best understanding existing

It be of conditions and could significantly affected major changes either the reservoirs The

be by to of assumptions this analysis represent average reservoir conditions their current conditions

in In the Primary Ash and Secondary Ash Ponds associated with the Flint Creek Power Plant are deemed hydraulically adequate for any storm event to and including the 100 PMF

to be up

Pertinent drawings for existingconditions are included Appendix C

January 2011

16 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

Appendix A References

January 2011 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

References

1 US Army Corps Engineers Hydrologic Engineering Center Hydrologic Modeling

System HEC_ HMS _ User’s Manual Version 3.4 Davis California August 2009

2 “Soil Data Mart.” NRCS Soil Survey Geographic SSURGO Database

http soildatamart nrcsusdagov

3 “National Land Cover Dataset 2001.” USGS Seamless Data Warehouse August 30 2010 http seamlessusgs gov nlcd php

4 US Army Corps Engineers Hydrologic Engineering Center River Analysis System _

of User’s Manual Version 4.1 Davis California January 2010

5 US Department Commerce National Oceanic and Atmospheric Administration

Technical Memorandum NWS HYDRO_ 35 Five_ 60_ Minute Precipitation Frequency

to for the Eastern and CentralUnited States Silver Spring MD June 1977

6 US Department Commerce Weather Bureau Technical Paper No 40 Rainfall

Frequency Atlas the United States for Durations from Minutes Hours and

of 30 to 24 Return Periods from 1 100 Years Washington DC May 1961

7 US Department Commerce National Oceanic and Atmospheric Administration and

of US Department the Army Corps Engineers Hydrometeorological Report No 52

of of Application Probable Maximum Precipitation Estimates United States East the

of of 105th Meridian Washington DC 1982

8 US Department Commerce National Oceanic and Atmospheric Administration and

of US Department the Army Corps Engineers Hydrometeorological Report No 51

of of Probable Maximum Precipitation Estimates United States East the 105th Meridian

of Washington DC 1978

January 2011 Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

Appendix B Discharge Rating Curve Calculations and Hydrologic Parameters

January 2011 Primary Ash Pond Secondary Ash Pond

Weir Box Weir Box from Plans

Elevation Discharge Elevation Discharge Discharge

msl cfs msl MGD cfs

ft_ ft_

1144 0.00 1142.50 0.000 0.000

1145 12.65 1142.70 2.495 3.860

1146 33.91 1142.88 6.387 9.882

Q 3.33 0.2H 1.5 1143.95 47.806 73.967

L_ H

L 4 1145.00 106.332 164.520

Assumed rectangular sharpcrested Values taken from plans

weir equation with end for

design new spillway linear

contractions accounted for of congruent with calculations interpolation between points made AEP

by HECRAS Plan PrimarySpwy River Primary Reach Spwy

Reach River Sta Profile QTotal Min W S Elev Crit W SEG Elev EG Slope Vel Chnl Flow Area Top Width Froude Chl

Ch El

cfs

ft sq ft ft ft ft ft ft ft sft

Spwy 3045 PF 1 1.00 1144.00 1146.06 1146.06 0.000000 0.00 2396.65 1180.88 0.00

Spwy 3045 PF 2 10.00 1144.00 1146.19 1146.19 0.000000 0.00 2545.85 1183.29 0.00

Spwy 3045 PF 3 50.00 1144.00 1146.41 1146.41 0.000000 0.02 2801.38 1187.40 0.00

Spwy 3045 4 100.00 1144.00 1146.57 1146.57 0.000000 0.03 2995.43 1190.52 0.00

Spwy 3045 PF 5 250.00 1144.00 1146.91 1146.91 0.000002 0.07 3400.39 1196.99 0.01

Spwy 3045 PF 6 500.00 1144.00 1147.32 1147.32 0.000004 0.13 3889.13 1204.76 0.01

Spwy 3045 7 750.00 1144.00 1147.64 1147.64 0.000006 0.18 4282.36 1210.97 0.02

Spwy 3045 PF 8 1000.00 1144.00 1147.93 1147.93 0.000009 0.22 4629.79 1216.44 0.02

Spwy 3045 PF 9 1500.00 1144.00 1148.42 1148.42 0.000013 0.29 5229.47 1225.81 0.02

Spwy 3045 2000.00 1144.00 1148.85 1148.85 0.000017 0.35 5757.49 1234.00 0.03

PF 10

Spwy 3045 PF 2500.00 1144.00 1149.20 1149.21 0.000021 0.41 6196.28 1240.77 0.03

Spwy 3045 PF 3000.00 1144.00 1149.57 1149.57 0.000024 0.46 6653.47 1247.78 0.03

Spwy 3045 3500.00 1144.00 1149.93 1149.93 0.000027 0.50 7100.37 1254.60 0.04

PF 13 Spwy 3045 PF 4000.00 1144.00 1150.27 1150.27 0.000029 0.54 7531.30 1259.46 0.04

Spwy 3045 PF 5000.00 1144.00 1150.91 1150.92 0.000032 0.61 8344.34 1267.72 0.04

Spwy 3045 PF 6000.00 1144.00 1151.51 1151.52 0.000035 0.68 9101.64 1275.37 0.04

Spwy 3045 PF 7000.00 1144.00 1152.07 1152.07 0.000038 0.73 9813.08 1282.51 0.05

Spwy 3045 PF 8000.00 1144.00 1152.59 1152.60 0.000040 0.79 10485.21 1289.22 0.05

Spwy 3045 PF 9000.00 1144.00 1153.08 1153.09 0.000042 0.83 11123.51 1295.51 0.05

Spwy 3045 PF 10000.00 1144.00 1153.55 1153.56 0.000043 0.88 11734.40 1301.50 0.05

Spwy 3045 PF 11000.00 1144.00 1154.00 1154.01 0.000045 0.92 12321.14 1307.22 0.05

Spwy 3045 PF 12000.00 1144.00 1154.43 1154.45 0.000046 0.96 12886.09 1312.70 0.05

Spwy 3045 PF 13000.00 1144.00 1154.85 1154.87 0.000047 1.00 13436.67 1318.01 0.05

Spwy 3045 PF 14000.00 1144.00 1155.25 1155.27 0.000048 1.04 13967.30 1321.54 0.05

Spwy 3045 PF 15000.00 1144.00 1155.64 1155.66 0.000050 1.07 14482.41 1324.08 0.06

Spwy 2645 PF 1 1.00 1144.00 1146.06 1146.06 0.000000 0.00 1052.44 540.92 0.00

Spwy 2645 PF 2 10.00 1144.00 1146.19 1146.19 0.000000 0.01 1120.95 544.71 0.00

Spwy 2645 3 50.00 1144.00 1146.41 1146.41 0.000001 0.04 1239.01 551.19 0.00

Spwy 2645 PF 4 100.00 1144.00 1146.57 1146.57 0.000002 0.08 1329.23 556.09 0.01

Spwy 2645 PF 5 250.00 1144.00 1146.91 1146.91 0.000008 0.17 1518.91 566.24 0.02

Spwy 2645 6 500.00 1144.00 1147.31 1147.31 0.000021 0.30 1750.30 578.39 0.03

Spwy 2645 PF 7 750.00 1144.00 1147.63 1147.64 0.000034 0.41 1938.54 588.09 0.04

Spwy 2645 PF 8 1000.00 1144.00 1147.92 1147.92 0.000046 0.50 2106.30 596.60 0.04

Spwy 2645 9 1500.00 1144.00 1148.40 1148.41 0.000069 0.66 2399.40 611.18 0.06

Spwy 2645 PF 2000.00 1144.00 1148.83 1148.84 0.000089 0.80 2661.06 623.92 0.06

Spwy 2645 PF 2500.00 1144.00 1149.17 1149.19 0.000109 0.93 2880.32 634.39 0.07

Spwy 2645 3000.00 1144.00 1149.54 1149.55 0.000124 1.04 3112.38 645.29 0.08

PF 12 Spwy 2645 PF 3500.00 1144.00 1149.89 1149.91 0.000136 1.13 3341.89 655.89 0.08

Spwy 2645 PF 4000.00 1144.00 1150.23 1150.25 0.000146 1.22 3565.68 664.73 0.09

Spwy 2645 PF 5000.00 1144.00 1150.87 1150.89 0.000162 1.36 3993.34 679.27 0.09

Spwy 2645 PF 6000.00 1144.00 1151.45 1151.49 0.000174 1.49 4397.45 692.66 0.10

Spwy 2645 PF 7000.00 1144.00 1152.01 1152.04 0.000183 1.61 4782.14 705.17 0.10

Spwy 2645 PF 8000.00 1144.00 1152.52 1152.56 0.000192 1.72 5151.01 722.17 0.10

Spwy 2645 PF 9000.00 1144.00 1153.01 1153.06 0.000199 1.82 5507.16 734.88 0.11

Spwy 2645 PF 10000.00 1144.00 1153.48 1153.53 0.000205 1.91 5852.04 746.26 0.11

Spwy 2645 PF 11000.00 1144.00 1153.92 1153.98 0.000211 1.99 6186.67 758.37 0.11

Spwy 2645 PF 12000.00 1144.00 1154.35 1154.41 0.000216 2.07 6513.57 773.21 0.11

Spwy 2645 PF 13000.00 1144.00 1154.76 1154.83 0.000220 2.15 6836.81 787.62 0.12

Spwy 2645 PF 14000.00 1144.00 1155.16 1155.23 0.000224 2.22 7152.83 800.63 0.12

Spwy 2645 PF 15000.00 1144.00 1155.55 1155.62 0.000228 2.29 7463.77 812.08 0.12

Spwy 2090 PF 1 1.00 1144.00 1146.06 1146.06 0.000000 0.00 439.34 223.25 0.00

Spwy 2090 2 10.00 1144.00 1146.19 1146.19 0.000000 0.02 467.60 224.52 0.00

Spwy 2090 PF 3 50.00 1144.00 1146.41 1146.41 0.000003 0.10 516.01 226.69 0.01

Spwy 2090 PF 4 100.00 1144.00 1146.57 1146.57 0.000011 0.19 552.70 228.31 0.02

Spwy 2090 5 250.00 1144.00 1146.90 1146.90 0.000046 0.41 628.44 231.63 0.04

Spwy 2090 PF 6 500.00 1144.00 1147.28 1147.29 0.000121 0.72 718.48 235.51 0.07

Spwy 2090 PF 7 750.00 1144.00 1147.58 1147.60 0.000202 0.99 790.00 238.55 0.09

Spwy 2090 8 1000.00 1144.00 1147.84 1147.87 0.000282 1.22 852.81 241.18 0.11

Spwy 2090 PF 9 1500.00 1144.00 1148.29 1148.33 0.000436 1.64 960.49 245.64 0.14

Spwy 2090 PF 2000.00 1144.00 1148.67 1148.73 0.000578 2.00 1055.05 249.48 0.16

Spwy 2090 2500.00 1144.00 1148.97 1149.05 0.000726 2.33 1131.50 252.55 0.18

PF 11

Spwy 2090 PF 3000.00 1144.00 1149.30 1149.40 0.000840 2.62 1214.22 255.83 0.20

Spwy 2090 PF 3500.00 1144.00 1149.62 1149.74 0.000933 2.87 1296.46 259.04 0.21

Spwy 2090 PF 4000.00 1144.00 1149.93 1150.07 0.001013 3.10 1376.78 262.15 0.22

Spwy 2090 PF 5000.00 1144.00 1150.51 1150.69 0.001141 3.50 1530.63 266.97 0.24

Spwy 2090 PF 6000.00 1144.00 1151.05 1151.26 0.001243 3.85 1675.69 271.22 0.26

Spwy 2090 PF 7000.00 1144.00 1151.55 1151.80 0.001327 4.17 1813.49 275.19 0.27

Spwy 2090 PF 8000.00 1144.00 1152.02 1152.31 0.001400 4.46 1944.51 278.92 0.28

Spwy 2090 PF 9000.00 1144.00 1152.47 1152.79 0.001465 4.73 2069.87 282.44 0.29

Spwy 2090 PF 10000.00 1144.00 1152.90 1153.25 0.001521 4.98 2190.84 285.79 0.29

Spwy 2090 PF 11000.00 1144.00 1153.30 1153.69 0.001572 5.21 2307.63 288.99 0.30

Spwy 2090 PF 12000.00 1144.00 1153.69 1154.11 0.001618 5.43 2420.69 292.06 0.31

Spwy 2090 PF 13000.00 1144.00 1154.07 1154.53 0.001659 5.64 2531.70 295.04 0.31

Spwy 2090 PF 14000.00 1144.00 1154.43 1154.92 0.001697 5.85 2639.15 297.89 0.32

24 Spwy 2090 PF 15000.00 1144.00 1154.78 1155.30 0.001732 6.04 2744.33 300.66 0.32

Spwy 2040 1 1.00 1146.00 1146.06 1146.06 0.000210 0.07 14.54 227.98 0.05

1 HECRAS Plan PrimarySpwy River Primary Reach Spwy Continued

Reach River Sta Profile QTotal Min W S Elev Crit W SEG Elev EG Slope Vel Chnl Flow Area Top Width Froude Chl

Ch El

cfs

ft sq ft ft ft ft ft ft ft sft

Spwy 2040 PF 2 10.00 1146.00 1146.19 1146.03 1146.19 0.000561 0.23 43.17 228.74 0.09

Spwy 2040 PF 3 50.00 1146.00 1146.40 1146.11 1146.40 0.001164 0.55 91.24 229.99 0.15

Spwy 2040 PF 4 100.00 1146.00 1146.55 1146.18 1146.56 0.001564 0.79 126.75 230.92 0.19

Spwy 2040 5 250.00 1146.00 1146.86 1146.34 1146.88 0.002238 1.27 197.81 232.76 0.24

Spwy 2040 PF 6 500.00 1146.00 1147.21 1146.53 1147.26 0.002869 1.80 279.18 234.84 0.29

Spwy 2040 PF 7 750.00 1146.00 1147.47 1146.69 1147.55 0.003307 2.21 342.03 236.44 0.32

Spwy 2040 8 1000.00 1146.00 1147.70 1146.84 1147.80 0.003616 2.55 396.54 237.82 0.34

Spwy 2040 PF 9 1500.00 1146.00 1148.09 1147.10 1148.24 0.004114 3.11 488.22 240.13 0.38

Spwy 2040 PF 2000.00 1146.00 1148.42 1147.33 1148.61 0.004462 3.58 567.90 242.11 0.41

Spwy 2040 2500.00 1146.00 1148.66 1148.92 0.005035 4.05 627.48 243.58 0.44

PF 11

Spwy 2040 PF 3000.00 1146.00 1148.95 1149.25 0.005131 4.38 697.84 245.31 0.45

Spwy 2040 PF 3500.00 1146.00 1149.24 1149.57 0.005078 4.64 769.82 247.06 0.45

Spwy 2040 4000.00 1146.00 1149.53 1149.89 0.004979 4.86 841.06 248.79 0.46

PF 14 Spwy 2040 PF 5000.00 1146.00 1150.08 1150.50 0.004769 5.24 978.69 252.08 0.46

Spwy 2040 PF 6000.00 1146.00 1150.60 1151.07 0.004591 5.57 1109.28 255.17 0.46

Spwy 2040 PF 7000.00 1146.00 1151.08 1151.60 0.004447 5.86 1233.52 258.08 0.46

Spwy 2040 PF 8000.00 1146.00 1151.53 1152.10 0.004339 6.12 1351.53 260.81 0.46

Spwy 2040 PF 9000.00 1146.00 1151.96 1152.58 0.004255 6.38 1464.21 263.39 0.46

Spwy 2040 PF 10000.00 1146.00 1152.38 1153.03 0.004186 6.61 1572.90 265.85 0.46

Spwy 2040 PF 11000.00 1146.00 1152.77 1153.47 0.004131 6.83 1677.54 268.20 0.46

Spwy 2040 PF 12000.00 1146.00 1153.14 1153.89 0.004086 7.05 1778.63 270.45 0.46

Spwy 2040 PF 13000.00 1146.00 1153.51 1154.29 0.004041 7.24 1878.01 272.65 0.47

Spwy 2040 PF 14000.00 1146.00 1153.86 1154.69 0.004009 7.44 1973.80 274.75 0.47

Spwy 2040 PF 15000.00 1146.00 1154.20 1155.07 0.003979 7.62 2067.42 276.79 0.47

Spwy 1980 PF 1 1.00 1146.00 1146.03 1146.03 1146.03 0.003444 0.16 6.28 227.77 0.17

Spwy 1980 PF 2 10.00 1146.00 1146.03 1146.03 1146.07 0.344390 1.59 6.28 227.77 1.69

Spwy 1980 PF 3 50.00 1146.00 1146.11 1146.11 1146.17 0.084653 1.99 25.15 228.26 1.06

Spwy 1980 4 100.00 1146.00 1146.18 1146.18 1146.27 0.064245 2.42 41.44 228.69 1.00

Spwy 1980 PF 5 250.00 1146.00 1146.34 1146.34 1146.50 0.052170 3.27 76.55 229.61 1.00

Spwy 1980 PF 6 500.00 1146.00 1146.53 1146.53 1146.79 0.045516 4.14 121.08 230.77 1.00

Spwy 1980 7 750.00 1146.00 1146.69 1146.69 1147.04 0.041388 4.73 159.14 231.76 1.00

Spwy 1980 PF 8 1000.00 1146.00 1146.84 1146.84 1147.26 0.039052 5.22 192.70 232.62 1.00

Spwy 1980 PF 9 1500.00 1146.00 1147.10 1147.10 1147.65 0.035580 5.96 253.33 234.18 1.00

Spwy 1980 2000.00 1146.00 1147.33 1147.33 1147.99 0.033347 6.56 307.60 235.57 1.00

PF 10

Spwy 1980 PF 2500.00 1146.00 1147.83 1148.37 0.017832 5.93 426.22 238.57 0.77

Spwy 1980 PF 3000.00 1146.00 1148.25 1148.76 0.012783 5.77 527.41 241.10 0.68

Spwy 1980 3500.00 1146.00 1148.63 1149.13 0.010361 5.76 618.18 243.35 0.63

PF 13 Spwy 1980 PF 4000.00 1146.00 1148.97 1149.48 0.008942 5.80 702.13 245.41 0.59

Spwy 1980 PF 5000.00 1146.00 1149.59 1150.13 0.007361 5.98 855.59 249.14 0.56

Spwy 1980 PF 6000.00 1146.00 1150.15 1150.73 0.006504 6.19 995.35 252.48 0.54

Spwy 1980 PF 7000.00 1146.00 1150.66 1151.28 0.005964 6.40 1125.52 255.55 0.52

Spwy 1980 PF 8000.00 1146.00 1151.13 1151.80 0.005605 6.62 1247.33 258.40 0.51

Spwy 1980 PF 9000.00 1146.00 1151.58 1152.28 0.005352 6.84 1362.45 261.06 0.51

Spwy 1980 PF 10000.00 1146.00 1152.00 1152.75 0.005155 7.04 1472.96 263.59 0.51

Spwy 1980 PF 11000.00 1146.00 1152.40 1153.19 0.005005 7.25 1578.75 265.98 0.50

Spwy 1980 PF 12000.00 1146.00 1152.78 1153.61 0.004888 7.44 1680.58 268.27 0.50

Spwy 1980 PF 13000.00 1146.00 1153.15 1154.02 0.004778 7.62 1780.75 270.50 0.50

Spwy 1980 PF 14000.00 1146.00 1153.50 1154.42 0.004696 7.81 1876.85 272.62 0.50

Spwy 1980 PF 15000.00 1146.00 1153.85 1154.80 0.004624 7.98 1970.72 274.68 0.50

Spwy 1865 PF 1 1.00 1142.50 1145.03 1145.03 0.000000 0.00 590.46 242.39 0.00

Spwy 1865 PF 2 10.00 1142.50 1145.06 1145.06 0.000000 0.02 598.04 242.61 0.00

Spwy 1865 3 50.00 1142.50 1145.17 1145.17 0.000002 0.08 625.80 243.39 0.01

Spwy 1865 PF 4 100.00 1142.50 1145.28 1145.28 0.000007 0.16 652.10 244.13 0.02

Spwy 1865 PF 5 250.00 1142.50 1145.55 1145.56 0.000032 0.36 719.08 246.00 0.04

Spwy 1865 6 500.00 1142.50 1145.94 1145.95 0.000086 0.63 815.36 248.66 0.06

Spwy 1865 PF 7 750.00 1142.50 1146.28 1146.30 0.000140 0.86 900.88 251.00 0.08

Spwy 1865 PF 8 1000.00 1142.50 1146.59 1146.61 0.000192 1.05 978.04 253.10 0.09

Spwy 1865 9 1500.00 1142.50 1147.13 1147.16 0.000283 1.39 1115.26 256.78 0.11

Spwy 1865 PF 2000.00 1142.50 1147.60 1147.64 0.000363 1.68 1236.37 259.99 0.13

Spwy 1865 PF 2500.00 1142.50 1148.02 1148.07 0.000433 1.93 1345.86 262.85 0.14

Spwy 1865 3000.00 1142.50 1148.40 1148.47 0.000495 2.16 1447.21 265.48 0.16

PF 12

Spwy 1865 PF 3500.00 1142.50 1148.75 1148.84 0.000553 2.37 1541.43 267.90 0.17

Spwy 1865 PF 4000.00 1142.50 1149.09 1149.18 0.000605 2.57 1630.75 270.17 0.18

Spwy 1865 PF 5000.00 1142.50 1149.69 1149.82 0.000697 2.92 1796.52 274.33 0.19

Spwy 1865 PF 6000.00 1142.50 1150.25 1150.40 0.000778 3.25 1949.23 278.15 0.21

Spwy 1865 PF 7000.00 1142.50 1150.76 1150.94 0.000850 3.54 2092.02 281.40 0.22

Spwy 1865 PF 8000.00 1142.50 1151.23 1151.45 0.000914 3.81 2226.56 284.42 0.23

Spwy 1865 PF 9000.00 1142.50 1151.68 1151.92 0.000974 4.07 2354.06 287.25 0.24

Spwy 1865 PF 10000.00 1142.50 1152.10 1152.38 0.001027 4.30 2476.62 289.95 0.24

Spwy 1865 PF 11000.00 1142.50 1152.51 1152.81 0.001077 4.53 2594.15 292.51 0.25

Spwy 1865 PF 12000.00 1142.50 1152.89 1153.22 0.001124 4.75 2707.35 294.96 0.26

Spwy 1865 PF 13000.00 1142.50 1153.27 1153.63 0.001166 4.95 2818.73 297.36 0.27

Spwy 1865 PF 14000.00 1142.50 1153.63 1154.01 0.001206 5.14 2925.72 299.65 0.27

Spwy 1865 PF 15000.00 1142.50 1153.97 1154.39 0.001244 5.33 3030.20 301.87 0.28

Spwy 1575 PF 1 1.00 1142.50 1145.03 1145.03 0.000000 0.00 924.26 390.65 0.00

Spwy 1575 2 10.00 1142.50 1145.06 1145.06 0.000000 0.01 936.47 391.27 0.00

2 HECRAS Plan PrimarySpwy River Primary Reach Spwy Continued

Reach River Sta Profile QTotal Min W S Elev Crit W SEG Elev EG Slope Vel Chnl Flow Area Top Width Froude Chl

Ch El

cfs

ft sq ft ft ft ft ft ft ft sft

Spwy 1575 PF 3 50.00 1142.50 1145.17 1145.17 0.000001 0.05 981.21 393.50 0.01

Spwy 1575 PF 4 100.00 1142.50 1145.28 1145.28 0.000003 0.10 1023.45 395.60 0.01

Spwy 1575 PF 5 250.00 1142.50 1145.55 1145.55 0.000014 0.23 1130.74 400.88 0.02

Spwy 1575 6 500.00 1142.50 1145.93 1145.93 0.000036 0.41 1285.04 408.36 0.04

Spwy 1575 PF 7 750.00 1142.50 1146.26 1146.27 0.000059 0.55 1422.82 414.92 0.05

Spwy 1575 PF 8 1000.00 1142.50 1146.56 1146.57 0.000081 0.68 1547.84 420.78 0.06

Spwy 1575 9 1500.00 1142.50 1147.09 1147.10 0.000119 0.90 1772.31 431.11 0.07

Spwy 1575 PF 2000.00 1142.50 1147.55 1147.57 0.000152 1.08 1972.73 440.13 0.08

Spwy 1575 PF 2500.00 1142.50 1147.96 1147.99 0.000181 1.24 2155.83 448.21 0.09

Spwy 1575 3000.00 1142.50 1148.34 1148.37 0.000206 1.38 2326.95 455.63 0.10

PF 12

Spwy 1575 PF 3500.00 1142.50 1148.69 1148.72 0.000229 1.52 2487.39 462.48 0.11

Spwy 1575 PF 4000.00 1142.50 1149.02 1149.06 0.000249 1.64 2640.71 468.94 0.11

Spwy 1575 5000.00 1142.50 1149.63 1149.68 0.000285 1.86 2928.41 480.81 0.12

PF 15 Spwy 1575 PF 6000.00 1142.50 1150.18 1150.24 0.000315 2.05 3196.82 491.14 0.13

Spwy 1575 PF 7000.00 1142.50 1150.69 1150.76 0.000341 2.23 3450.35 499.74 0.14

Spwy 1575 PF 8000.00 1142.50 1151.17 1151.25 0.000364 2.39 3691.22 507.78 0.14

Spwy 1575 PF 9000.00 1142.50 1151.62 1151.71 0.000384 2.54 3921.40 515.34 0.15

Spwy 1575 PF 10000.00 1142.50 1152.05 1152.15 0.000402 2.68 4144.25 522.56 0.15

Spwy 1575 PF 11000.00 1142.50 1152.46 1152.57 0.000419 2.81 4359.42 529.44 0.16

Spwy 1575 PF 12000.00 1142.50 1152.85 1152.97 0.000434 2.94 4568.04 536.02 0.16

Spwy 1575 PF 13000.00 1142.50 1153.23 1153.36 0.000447 3.06 4774.53 542.46 0.16

Spwy 1575 PF 14000.00 1142.50 1153.60 1153.74 0.000459 3.17 4974.04 548.60 0.17

Spwy 1575 PF 15000.00 1142.50 1153.95 1154.10 0.000470 3.27 5169.91 554.60 0.17

Spwy 1180 PF 1 1.00 1142.50 1145.03 1145.03 0.000000 0.00 390.05 173.31 0.00

Spwy 1180 PF 2 10.00 1142.50 1145.06 1145.06 0.000000 0.03 395.47 173.78 0.00

Spwy 1180 PF 3 50.00 1142.50 1145.17 1145.17 0.000005 0.13 415.21 175.47 0.01

Spwy 1180 PF 4 100.00 1142.50 1145.28 1145.28 0.000018 0.25 433.70 177.04 0.03

Spwy 1180 5 250.00 1142.50 1145.53 1145.54 0.000081 0.56 479.83 180.89 0.06

Spwy 1180 PF 6 500.00 1142.50 1145.89 1145.90 0.000219 0.99 544.83 186.19 0.10

Spwy 1180 PF 7 750.00 1142.50 1146.19 1146.22 0.000364 1.35 602.33 190.76 0.12

Spwy 1180 8 1000.00 1142.50 1146.46 1146.50 0.000505 1.67 654.19 194.78 0.15

Spwy 1180 PF 9 1500.00 1142.50 1146.93 1147.00 0.000765 2.22 746.99 201.78 0.19

Spwy 1180 PF 2000.00 1142.50 1147.33 1147.43 0.000996 2.68 829.61 207.82 0.21

Spwy 1180 2500.00 1142.50 1147.69 1147.83 0.001204 3.09 904.92 213.17 0.24

PF 11

Spwy 1180 PF 3000.00 1142.50 1148.02 1148.19 0.001392 3.46 975.38 218.06 0.26

Spwy 1180 PF 3500.00 1142.50 1148.32 1148.52 0.001566 3.80 1041.24 222.53 0.28

Spwy 1180 4000.00 1142.50 1148.60 1148.83 0.001724 4.12 1104.34 226.73 0.29

PF 14 Spwy 1180 PF 5000.00 1142.50 1149.11 1149.41 0.002006 4.69 1222.69 234.41 0.32

Spwy 1180 PF 6000.00 1142.50 1149.58 1149.94 0.002253 5.20 1333.24 241.36 0.34

Spwy 1180 PF 7000.00 1142.50 1150.00 1150.44 0.002469 5.66 1438.18 247.77 0.36

Spwy 1180 PF 8000.00 1142.50 1150.40 1150.90 0.002657 6.08 1538.34 252.83 0.38

Spwy 1180 PF 9000.00 1142.50 1150.78 1151.34 0.002828 6.47 1634.01 257.57 0.40

Spwy 1180 PF 10000.00 1142.50 1151.14 1151.76 0.002981 6.83 1726.93 262.23 0.41

Spwy 1180 PF 11000.00 1142.50 1151.48 1152.16 0.003123 7.17 1816.65 266.69 0.42

Spwy 1180 PF 12000.00 1142.50 1151.80 1152.54 0.003253 7.50 1903.74 270.94 0.43

Spwy 1180 PF 13000.00 1142.50 1152.12 1152.92 0.003362 7.79 1991.10 275.14 0.44

Spwy 1180 PF 14000.00 1142.50 1152.42 1153.28 0.003469 8.08 2075.19 279.12 0.45

Spwy 1180 PF 15000.00 1142.50 1152.72 1153.62 0.003565 8.36 2158.05 282.98 0.46

Spwy 1010 PF 1 1.00 1145.00 1145.03 1145.03 1145.03 0.003648 0.16 6.41 250.00 0.17

Spwy 1010 PF 2 10.00 1145.00 1145.04 1145.04 1145.06 0.120220 1.12 8.94 250.00 1.04

Spwy 1010 PF 3 50.00 1145.00 1145.12 1145.12 1145.16 0.054496 1.68 29.79 250.00 0.86

Spwy 1010 4 100.00 1145.00 1145.17 1145.17 1145.26 0.065680 2.34 42.69 250.00 1.00

Spwy 1010 PF 5 250.00 1145.00 1145.32 1145.32 1145.47 0.053522 3.18 78.70 250.00 1.00

Spwy 1010 PF 6 500.00 1145.00 1145.50 1145.50 1145.75 0.046081 4.00 124.85 250.00 1.00

Spwy 1010 7 750.00 1145.00 1145.65 1145.65 1145.98 0.042967 4.61 162.69 250.00 1.01

Spwy 1010 PF 8 1000.00 1145.00 1145.79 1145.79 1146.19 0.040015 5.06 197.60 250.00 1.00

Spwy 1010 PF 9 1500.00 1145.00 1146.04 1146.04 1146.56 0.036801 5.80 258.64 250.00 1.00

Spwy 1010 2000.00 1145.00 1146.25 1146.25 1146.89 0.034722 6.39 312.99 250.00 1.01

PF 10

Spwy 1010 PF 2500.00 1145.00 1146.46 1146.46 1147.19 0.032773 6.86 364.32 250.00 1.00

Spwy 1010 PF 3000.00 1145.00 1146.64 1146.64 1147.47 0.031783 7.31 410.43 250.00 1.01

Spwy 1010 3500.00 1145.00 1146.82 1146.82 1147.74 0.030795 7.70 454.74 250.00 1.01

PF 13

Spwy 1010 PF 4000.00 1145.00 1146.99 1146.99 1147.99 0.029938 8.05 497.13 250.00 1.01

Spwy 1010 PF 5000.00 1145.00 1147.31 1147.31 1148.47 0.028520 8.66 577.27 250.00 1.00

Spwy 1010 PF 6000.00 1145.00 1147.61 1147.61 1148.92 0.027434 9.20 652.16 250.00 1.00

Spwy 1010 PF 7000.00 1145.00 1147.89 1147.89 1149.35 0.026677 9.70 722.02 250.00 1.01

Spwy 1010 PF 8000.00 1145.00 1148.16 1148.16 1149.75 0.025989 10.14 789.06 250.00 1.01

Spwy 1010 PF 9000.00 1145.00 1148.42 1148.42 1150.14 0.025329 10.54 854.10 250.00 1.00

Spwy 1010 PF 10000.00 1145.00 1148.66 1148.66 1150.52 0.024854 10.92 915.71 250.00 1.01

Spwy 1010 PF 11000.00 1145.00 1148.91 1148.91 1150.88 0.024290 11.26 977.05 250.00 1.00

Spwy 1010 PF 12000.00 1145.00 1149.15 1149.15 1151.23 0.023703 11.56 1037.78 250.00 1.00

Spwy 1010 PF 13000.00 1145.00 1149.37 1149.37 1151.57 0.023587 11.91 1091.16 250.00 1.00

Spwy 1010 PF 14000.00 1145.00 1149.59 1149.59 1151.90 0.023226 12.21 1146.85 250.00 1.00

Spwy 1010 PF 15000.00 1145.00 1149.81 1149.81 1152.23 0.022894 12.49 1201.29 250.00 1.00

Spwy 980 1 1.00 1138.41 1138.63 1138.64 0.012975 0.76 1.31 12.25 0.41

Spwy 980 2 10.00 1138.41 1138.92 1138.96 0.012867 1.63 6.13 18.08 0.49

Spwy 980 3 50.00 1138.41 1139.48 1139.61 0.012670 2.88 17.34 21.36 0.56

3 HECRAS Plan PrimarySpwy River Primary Reach Spwy Continued

Reach River Sta Profile QTotal Min W S Elev Crit W SEG Elev EG Slope Vel Chnl Flow Area Top Width Froude Chl

Ch El

cfs

ft sq ft ft ft ft ft ft ft sft

Spwy 980 4 100.00 1138.41 1139.94 1140.14 0.012492 3.61 27.71 23.99 0.59

PF Spwy 980 5 250.00 1138.41 1140.87 1141.22 0.012257 4.76 52.49 29.35 0.63

Spwy 980 6 500.00 1138.41 1141.91 1142.44 0.012095 5.80 86.24 35.37 0.65

Spwy 980 7 750.00 1138.41 1142.57 1141.87 1143.24 0.012393 6.66 124.28 107.75 0.68

Spwy 980 8 1000.00 1138.41 1143.02 1143.02 1143.69 0.011107 6.94 198.91 190.22 0.66

Spwy 980 9 1500.00 1138.41 1143.52 1143.52 1144.24 0.011428 7.71 297.85 207.21 0.69

Spwy 980 2000.00 1138.41 1143.86 1143.86 1144.66 0.012474 8.51 368.85 215.15 0.73

PF 10

Spwy 980 2500.00 1138.41 1144.20 1144.15 1145.03 0.012449 8.95 443.19 223.15 0.74

PF 11

Spwy 980 3000.00 1138.41 1144.50 1144.42 1145.37 0.012396 9.32 511.36 228.47 0.74

PF 12

Spwy 980 3500.00 1138.41 1144.77 1145.67 0.012316 9.63 574.02 230.71 0.75

PF 13

Spwy 980 4000.00 1138.41 1145.03 1145.96 0.012243 9.91 633.07 232.80 0.75

PF 14

Spwy 980 5000.00 1138.41 1145.49 1146.49 0.012123 10.43 742.92 236.65 0.76

PF 15

Spwy 980 6000.00 1138.41 1145.92 1146.99 0.012022 10.88 844.72 240.16 0.76

PF 16 Spwy 980 7000.00 1138.41 1146.32 1147.45 0.011945 11.29 940.23 243.40 0.77

PF 17

Spwy 980 8000.00 1138.41 1146.69 1147.89 0.011881 11.67 1030.88 246.44 0.77

PF 18

Spwy 980 9000.00 1138.41 1147.04 1148.31 0.011824 12.03 1117.69 249.32 0.78

PF 19

Spwy 980 10000.00 1138.41 1147.37 1148.72 0.011772 12.36 1201.29 252.06 0.78

PF 20

Spwy 980 11000.00 1138.41 1147.69 1149.10 0.011728 12.67 1282.05 254.67 0.79

PF 21

Spwy 980 12000.00 1138.41 1148.00 1149.47 0.011668 12.96 1361.15 257.21 0.79

PF 22

Spwy 980 13000.00 1138.41 1148.29 1149.83 0.011654 13.25 1436.48 259.61 0.79

PF 23

Spwy 980 14000.00 1138.41 1148.57 1150.18 0.011617 13.52 1510.97 261.95 0.80

PF 24

Spwy 980 15000.00 1138.41 1148.85 1150.52 0.011587 13.78 1583.58 264.22 0.80

PF 25

Spwy 680 1 1.00 1135.00 1135.23 1135.15 1135.23 0.009998 0.69 1.44 12.74 0.36

Spwy 680 2 10.00 1135.00 1135.53 1135.37 1135.57 0.010009 1.51 6.63 18.24 0.44

Spwy 680 3 50.00 1135.00 1136.14 1135.79 1136.25 0.010003 2.67 18.75 21.74 0.51

PF Spwy 680 4 100.00 1135.00 1136.62 1136.14 1136.80 0.010019 3.35 29.87 24.51 0.53

Spwy 680 5 250.00 1135.00 1137.59 1136.90 1137.90 0.010000 4.43 56.38 30.11 0.57

Spwy 680 6 500.00 1135.00 1138.66 1137.78 1139.12 0.010009 5.44 92.27 42.73 0.60

Spwy 680 7 750.00 1135.00 1139.31 1138.46 1139.88 0.010016 6.19 143.86 151.04 0.62

Spwy 680 8 1000.00 1135.00 1139.68 1139.62 1140.28 0.010010 6.67 211.16 192.63 0.63

Spwy 680 9 1500.00 1135.00 1140.20 1140.11 1140.83 0.010004 7.32 316.31 209.34 0.65

Spwy 680 2000.00 1135.00 1140.61 1140.47 1141.27 0.010002 7.81 404.24 219.03 0.66

PF 10

Spwy 680 2500.00 1135.00 1140.96 1140.74 1141.65 0.010002 8.23 483.28 227.39 0.66

PF 11

Spwy 680 3000.00 1135.00 1141.27 1141.01 1141.99 0.010009 8.58 553.34 229.99 0.67

PF 12

Spwy 680 3500.00 1135.00 1141.55 1141.22 1142.31 0.010005 8.89 618.55 232.31 0.68

PF 13

Spwy 680 4000.00 1135.00 1141.82 1141.44 1142.60 0.010003 9.18 679.91 234.47 0.68

PF 14

Spwy 680 5000.00 1135.00 1142.30 1141.79 1143.15 0.010001 9.70 793.98 238.43 0.69

PF 15 Spwy 680 6000.00 1135.00 1142.74 1142.12 1143.66 0.010013 10.16 899.08 242.03 0.70

PF 16

Spwy 680 7000.00 1135.00 1143.14 1142.42 1144.14 0.010007 10.58 998.26 245.37 0.71

PF 17

Spwy 680 8000.00 1135.00 1143.52 1142.72 1144.59 0.010003 10.96 1092.37 248.50 0.71

PF 18

Spwy 680 9000.00 1135.00 1143.88 1142.98 1145.01 0.010003 11.32 1182.21 251.45 0.72

PF 19

Spwy 680 10000.00 1135.00 1144.23 1143.27 1145.42 0.010002 11.65 1268.66 254.26 0.72

PF 20

Spwy 680 11000.00 1135.00 1144.55 1143.55 1145.81 0.010001 11.96 1352.19 256.95 0.73

PF 21

Spwy 680 12000.00 1135.00 1144.86 1143.77 1146.19 0.010016 12.27 1432.41 259.50 0.73

PF 22

Spwy 680 13000.00 1135.00 1145.17 1144.01 1146.55 0.010012 12.55 1511.28 261.98 0.74

PF 23

Spwy 680 14000.00 1135.00 1145.46 1144.24 1146.90 0.010008 12.82 1588.16 264.38 0.74

PF 24

Spwy 680 15000.00 1135.00 1145.74 1144.47 1147.24 0.010005 13.08 1663.20 266.71 0.75

PF 25

4 PrimarySpwy Plan PrimarySpwy 1 2011 PrimarySpwy Plan PrimarySpwy 1 2011

10 10

River Primary Reach Spwy RS 3045 River Primary Reach Spwy RS 2645

05 06

1162 Legend 1170 Legend

06 06 WS 06 WS

PF PF 25 25

WS WS

PF PF 24 24 1160 WS PF 23 WS PF 23 WS WS

PF PF 22 1165 22 WS WS

PF PF 21 21

1158 WS WS

PF PF 20 20 WS WS

PF PF 19 19 WS WS

PF PF 18 18 WS WS

PF PF 1156 17 1160 17 WS WS

PF PF 16 16 WS WS

PF PF ft 15 ft 15 1154 WS PF 14 WS PF 14 WS WS

PF PF 13 13 WS 1155 WS

PF PF 12 12 WS WS

PF PF 1152 11 11

Elevation WS Elevation WS

PF PF 10 10

WS PF 9 WS PF 9

WS PF 8 WS PF 8 1150 1150 WS PF 7 WS PF 7

WS PF 6 WS PF 6

WS PF 5 WS PF 5 1148 WS PF 4 WS PF 4

WS PF 3 1145 WS PF 3

WS PF 2 WS PF 2 1146 WS PF 1 WS PF 1

Ground Ground

Bank Sta Bank Sta 1144 1140 0 200 400 600 800 1000 1200 1400 0 200 400 600 800 1000 1200

Station Station

ft ft

PrimarySpwy Plan PrimarySpwy 1 2011 PrimarySpwy Plan PrimarySpwy 1 2011

10 10

River Primary Reach Spwy RS 2040 Primary Spillway River Primary Reach Spwy RS 2090 06 05

1170 Legend 1156 Legend

06 WS 06 06 WS

PF PF 25 25

WS WS

PF PF 24 24

WS PF 23 WS PF 23 WS WS

PF PF 1165 22 22 WS WS

PF PF 21 1154 21 WS WS

PF PF 20 20 WS WS

PF PF 19 19 WS WS

PF PF 18 18 WS WS

PF PF 1160 17 17 WS WS

PF PF 16 16 WS 1152 WS

PF PF ft 15 ft 15 WS PF 14 WS PF 14

WS WS

PF PF 13 13

1155 WS WS

PF PF 12 12 WS WS

PF PF 11 11

Elevation WS Elevation WS

PF PF 10 1150 10 WS PF 9 WS PF 9

WS PF 8 WS PF 8 1150 WS PF 7 WS PF 7

WS PF 6 WS PF 6

WS PF 5 WS PF 5

WS PF 4 1148 WS PF 4

1145 WS PF 3 WS PF 3

WS PF 2 WS PF 2

WS PF 1 WS PF 1

Ground Ground

Bank Sta Bank Sta 1140 1146 0 100 200 300 400 500 600 0 100 150 200 250 300

Station Station

ft ft

1 PrimarySpwy Plan PrimarySpwy 1 2011 PrimarySpwy Plan PrimarySpwy 1 2011

10 10

River Primary Reach Spwy RS 1980 Primary Spillway River Primary Reach Spwy RS 1865

06 05

1156 Legend 1170 Legend

06 06 WS 06 WS

PF PF 25 25

WS WS

PF PF 24 24

WS PF 23 WS PF 23 WS WS

PF PF 22 1165 22 WS WS

PF PF 1154 21 21 WS WS

PF PF 20 20 WS WS

PF PF 19 19 WS WS

PF PF 18 18 WS WS

PF PF 17 1160 17 WS WS

PF PF 16 16 1152 WS WS

PF PF ft 15 ft 15 WS PF 14 WS PF 14

WS WS

PF PF 13 13 WS 1155 WS

PF PF 12 12 WS WS

PF PF 11 11

Elevation WS Elevation WS

PF PF 10 10 1150 WS PF 9 WS PF 9

WS PF 8 WS PF 8 1150 WS PF 7 WS PF 7

WS PF 6 WS PF 6

WS PF 5 WS PF 5

1148 WS PF 4 WS PF 4

WS PF 3 1145 WS PF 3

WS PF 2 WS PF 2

WS PF 1 WS PF 1

Ground Ground

Bank Sta Bank Sta 1146 1140 0 100 150 200 250 300 0 100 200 300 400 500

Station Station

ft ft

PrimarySpwy Plan PrimarySpwy 1 2011 PrimarySpwy Plan PrimarySpwy 1 2011

10 10

River Primary Reach Spwy RS 1575 River Primary Reach Spwy RS 1180 06 05 06 05

1165 Legend 1160 Legend

06 WS WS

PF PF 25 25

WS WS

PF PF 24 24

WS PF 23 WS PF 23 WS WS

PF PF 22 22 WS WS

PF PF 1160 21 21 WS WS

PF PF 20 20 WS 1155 WS

PF PF 19 19 WS WS

PF PF 18 18 WS WS

PF PF 17 17

WS WS

PF PF 16 16 1155 WS WS

PF PF ft 15 ft 15 WS PF 14 WS PF 14

WS WS

PF PF 13 13

WS 1150 WS

PF PF 12 12 WS WS

PF PF 11 11

Elevation WS Elevation WS

PF PF 1150 10 10 WS PF 9 WS PF 9

WS PF 8 WS PF 8

WS PF 7 WS PF 7

WS PF 6 WS PF 6 1145 WS PF 5 WS PF 5

1145 WS PF 4 WS PF 4

WS PF 3 WS PF 3

WS PF 2 WS PF 2

WS PF 1 WS PF 1

Ground Ground

Bank Sta Bank Sta 1140 1140 0 200 400 600 800 0 100 150 200 250 300 350 400

Station Station

ft ft

2 PrimarySpwy Plan PrimarySpwy 1 2011 PrimarySpwy Plan PrimarySpwy 1 2011

10 10

River Primary Reach Spwy RS 1010 Secondary Spillway River Primary Reach Spwy RS 980 Surveyed XS

05 06 05 06

1156 Legend 1156 Legend

WS WS

PF PF 25 25

WS WS

PF PF 24 24 1154 WS PF 23 WS PF 23 WS WS

PF PF 1154 22 22 WS WS

PF PF 21 21

WS 1152 WS

PF PF 20 20 WS WS

PF PF 19 19 WS WS

PF PF 18 18 WS WS

PF PF 1152 17 1150 17 WS WS

PF PF 16 16 WS WS

PF PF ft 15 ft 15 WS PF 14 1148 WS PF 14 WS WS

PF PF 13 13 1150 WS WS

PF PF 12 12 WS WS

PF PF 11 1146 11

Elevation WS Elevation WS

PF PF 10 10

WS PF 9 WS PF 9

WS PF 8 WS PF 8 1148 1144 WS PF 7 WS PF 7

WS PF 6 WS PF 6

WS PF 5 WS PF 5 1142 WS PF 4 WS PF 4

1146 WS PF 3 WS PF 3

WS PF 2 WS PF 2 1140 WS PF 1 WS PF 1

Ground Ground

Bank Sta Bank Sta 1144 1138 0 100 150 200 250 0 100 200 300 400

Station Station

ft ft

PrimarySpwy Plan PrimarySpwy 1 2011

River Primary Reach Spwy RS 680 Flint Creek Reservoir NP 1135

06 05 06

1152 Legend

PF 25

PF 24 1150 WS PF 23 WS

PF 22 WS

PF 21

1148 WS

PF 20 WS

PF 19 WS

PF 18 WS

PF 1146 17 WS

PF 16 WS

PF ft 15 1144 WS PF 14 WS

PF 13

PF 12 WS

PF 1142 11

Elevation WS

PF 10

WS PF 9

WS PF 8 1140 WS PF 7

WS PF 6

WS PF 5 1138 WS PF 4

WS PF 3

WS PF 2 1136 WS PF 1

Ground

Bank Sta 1134 0 100 200 300 400

Station

3 PrimarySpwy Plan PrimarySpwy 1102011

Primary Spwy 1160 Legend

PF 25 WS

PF 24 WS

PF 23 WS

PF 22 WS

PF 21 1155 WS PF

20 WS

PF 19 WS

PF 18

WS PF

17 WS

PF 16 WS 1150 PF 15 WS PF

14 ft WS

PF 13 WS

PF 12

WS PF

Elevation WS

PF 10

WS 9

1145 PF

WS PF 8

WS 7

WS 6

WS PF 5

WS 4

1140 WS 3

WS 2

WS 1

Spillway Spillway Ground

Surveyed Primary Primary 1135 500 1000 1500 2000 2500 3000 3500

Main Channel Distance

ft BASIN LAG TIME CALCULATION USING NRCS TR55 METHOD TO COMPUTE TIME OF CONCENTRATION

Existing Conditions

Project Data Comments PROJECT AEP10412

LOCATION Welsh Power Plant DATE Dec

10 BASIN COND BY JPM WSHED NAME Primary SHEET FLOW 100 MAX

Land Use

Undeveloped n value Land use Inc n

Conc gravel asphalt bare soil 0.015 0 0

Grass Short Prairie 0.15 0 0

Maintained Grass 0.03 0 0

Woods Light Underbrush 0.4 0 0

Woods Dense underbrush 0 0

0.8 based information imperviousness from Corps Engineers

on for of Land Use Conc Grass n value Land Use Inc n

Low D Residential 1 Acres 0.21375 0 0

75 25 Med D Residential 1 3 Acres 0.17135 100 0.17135

59 41 High D Residential 1 4 Acres 0.15545 0 0

53 47

Multifamily 0.0945 0 0

30 70

Mobile Home Parks 0.227 0 0

80 20 CBD 5 0.02825 0 0

Strip Commercial 0.0415 0 0

10 90

Shopping Center 5 0.02825 0 0

Instutional Schools 0.174 0 0

60 40

Industrial 0.0415 0 0

10 90 Highway ROW 0.18725 0 0

65 35

Public Utilities 0.121 0 0

40 60

Vacant urban land and 6 0.2361 0 0

Parks 0 0 0 0

Other 0 0 0 0 0

TOTAL 100 0.17135

LENGTH 100 FT MAX 100 n_ L 0.8 T _ 0.007 _ 2 YR HOUR PRECIP 4.31 IN 1 0.5 0.4 24 R _ S SLOPE 0.010 FT FT SHALLOW CONCENTRATED FLOW 1PAVED 2UNPAVED 1 L LENGTH 2362.91 T _

FT 2 SLOPE 0.006 FT FT _ V

60 COMPUTED VELOCITY FROM FIGURE 3.1 1.508 T 5 _ 60 L_ V CHANNEL FLOW

TOPWIDTH 2

35 1 _ a _ 3 XSECT AREA 100.000 SQ BOTTOM 5 _ _ s 2

FT 1 _ _

49 _ _ _ p _ DEPTH 5 V _ w WETTED PERIMETER 36.623 n

FT SLOPE 0.008 FT FT L MANNINGS N 0.06 _ T 6 COMPUTED VELOCITY 4.258 FT S _ V LENGTH 9995.43 FT 60

Conditions Adjusted NRCS Method Selected

WATERSHED NUMBER Primary Min Min Min

Tc Tc Tc

SHEET FLOW Max Min 30.0 12.39 12.39

30 SHALLOW CONCENTRATED FLOW 26.12 26.12

CHANNEL FLOW 39.12 39.12

TOTAL 77.63 77.63 T c T 1 T 2 T 3 T 4 T 5 T 6

Lag Hrs 0.78

Lagmin 46.58 BASIN LAG TIME CALCULATION USING NRCS TR55 METHOD TO COMPUTE TIME OF CONCENTRATION

Existing Conditions

Project Data Comments PROJECT AEP10412

LOCATION Welsh Power Plant DATE Dec

10 BASIN COND BY JPM WSHED NAME Secondary SHEET FLOW 100 MAX

Land Use

Undeveloped n value Land use Inc n

Conc gravel asphalt bare soil 0.015 0 0

Grass Short Prairie 0.15 100 0.15

Maintained Grass 0.03 0 0

Woods Light Underbrush 0.4 0 0

Woods Dense underbrush 0 0

0.8

TOTAL 100 0.15 LENGTH 100 FT MAX 100 n_ L 0.8 T _ 0.007 _ 2 YR HOUR PRECIP 4.31 IN 1 0.5 0.4 24 R _ S SLOPE 0.020 FT FT SHALLOW CONCENTRATED FLOW 1PAVED 2UNPAVED 2 L LENGTH 1159.16 FT _ T 2 0.017 _ V SLOPE FT FT 60 COMPUTED VELOCITY FROM FIGURE 3.1 2.119

Conditions Adjusted NRCS Method Selected

WATERSHED NUMBER Secondary Min Min Min

Tc Tc Tc SHEET FLOW Max Min 30.0 8.44 8.44

30 SHALLOW CONCENTRATED FLOW 9.12 9.12 T T T T T T T TOTAL 17.56 17.56 c 1 2 3 4 5 6

Lag Hrs 0.18

Lagmin 10.53 Curve Number Basin Areaacre AMC

Primary 76.6 1127.5

Secondary 74.9 39.9

Curve Number Calculations Name GRIDCODE HSG Areaft 2 Area acre CN Inc CN

Primary W 492113.109 11.297 100 1.002 Basin Area acre

Primary W 6432.202 0.148 100 0.013 Primary 1127.47

23 Primary W 196628.865 4.514 100 0.400 Secondary 39.90

31 Primary W 151664.101 3.482 100 0.309

41 Primary W 22148.379 0.508 100 0.045

Primary W 58928.772 1.353 100 0.120

81 Primary B 219057.220 5.029 100 0.446

Primary B 412397.879 9.467 0.663

21 79

Primary B 511234.844 11.736 0.708

22 68

Primary B 656437.501 15.070 1.136

23 85

Primary B 336825.792 7.732 0.590

31 86

Primary B 1432215.235 32.879 1.750

41 60

Primary B 192038.278 4.409 0.239

71 61

Primary B 3304498.256 75.861 4.104

81 61

Primary B 53877.802 1.237 0.072

90 66

Primary C 10933.953 0.251 100 0.022

11 Primary C 2381557.518 54.673 4.170

21 86

Primary C 564650.628 12.963 0.908

22 79

Primary C 173626.908 3.986 0.318

23 90

Primary C 185483.243 4.258 0.344

31 91

Primary C 1450486.842 33.299 2.156

41 73

Primary C 335571.928 7.704 0.506

71 74 Primary C 24105757.161 553.392 36.321

81 74

Primary C 4267.451 0.098 0.007

90 77

Primary D 1245218.812 28.586 2.257

21 89

Primary D 1727655.376 39.662 2.955

22 84

Primary D 164748.228 3.782 0.309

23 92

Primary D 1950.419 0.045 0.004

31 94

Primary D 733098.073 16.830 1.179

41 79

Primary D 5876087.739 134.896 9.572

81 80

Primary B 1488256.200 34.166 2.788

24 92

Primary C 306439.480 7.035 0.587

24 94

Primary C 310317.021 7.124 0.594

24 94

Secondary B 60082.739 1.379 100 3.457

Secondary B 192385.993 4.417 60 6.642

Curve Number Calculations Name GRIDCODE HSG Areaft 2 Area acre CN Inc CN

Secondary B 90951.376 2.088 3.192

81 61

Secondary C 106317.260 2.441 100 6.117

Secondary C 107888.311 2.477 5.339

21 86

Secondary C 210068.421 4.823 8.824

41 73

Secondary C 33928.559 0.779 1.445

71 74

Secondary C 936337.296 21.495 39.868

81 74

Curve Number Calculations Curve Number GRIDCODE NLCD Description TR_ Description A B BC C CD D W

Open Water Water 100 100 100 100 100 100 100

Developed Open Space Open Space _ Poor 100

21 68 79 83 86 88 89

Developed Low Intensity Low Density Residential acre 100

22 51 68 74 79 82 84

Developed Medium Intensity High Density Residential 100

23 77 85 88 90 91 92

Developed High Intensity Commercial 100

24 89 92 93 94 95 95

Barren Land Fallow _ Bare 100

31 77 86 89 91 93 94

Deciduous Forest Woods _ Fair 100

41 36 60 67 73 76 79

Evergreen Gorest Woods _ Fair 100

42 36 60 67 73 76 79

Mixed Forest Woods _ Fair 100

43 36 60 67 73 76 79

ScrubShrub Brush _ Fair 100

52 35 56 63 70 74 77

Grassland Herbaceous Open Space _ Good 100

71 39 61 68 74 77 80

Pasture Hay Open Space _ Good 100

81 39 61 68 74 77 80

Cultivated Crops Row Crops _ Good 100

82 SR 67 78 82 85 87 89

Woody Wetlands Woods _ Poor 100

90 45 66 72 77 80 83

Curve Number Calculations Hydraulic Analysis Flint Creek Power Plant Ash Ponds

American Electric Power Company

Appendix C Pertinent Drawings

January 2011 SD

RRIMARY ASH SETTLING BASIN EL IL O

fn4•Y•i•S MCLn 2iL t1 • swvo k E•••3 yI•Jlrtr 3 w L

EL n

NOTES 1 SKrer4 Aa oo ssrnea •• FR3sw2

5oc•v•• ogo•• wn4 ywe N ay 0fU+0f a

ECONDAR ASI SETTLING 51N 5IJRFACE E 1142 07 asv L •hn•u 2n• •Tkkt•acy rccc SOU1WESTERN ELE RIO °OWER COMPANY

kw•uw F2956 1 i T J FLAT CREEK POWER PLANT s e wncw ASH BERM AND CONNECTING CANAL PLAN

ICE = PJO G I s

r IF

SECTI IN IT

FRIIMAR`I A HI

NOT

D6 E

DETAIL TYPICAL DIAPH

SECTION

SECTION Ic•

DETAIIL

ESI a a 60

top of CoCRLte IEa E• 4b0 wRrl3eRr

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SECTION PRIMARY CONTROL CANAL AND SPILLWAY

C SPI LWAY

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SECTION `GG

ASH POND SPILLWAY SECTIONS

FLINT CREEK POWER PLANT SOUTHWESTERN ELECTRIC POWER CO

a ••rbn ORMMTMRT

FCX 3 SCALE

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9411 D URINOI DOTE 50041E DWG NO InFtLL LONG 141005

I1 LIB I IGX9Z I U NT JlCADReglon V SWEPCOFlint Creeklnterndl drawingsfcx dD1ingsfcx92dwg 063010 09109 11681

1758

1615

Ask BASIN •ONSO4Jf•5

FLINT CREEK Pov Efl PL r SOUTHWESTERN ELECTRIC POWER CO I PCINCEPoh PATE SCALES Owc No REV Nc oRf1 1i18af

RELRASE_ F611 INfRicM11011 II 1656

I RI 15CRIRTI1N 5 Rw APTPP SHi I Ii NOTF

INSYT•uMENTATI ON To MEASURE HEAD Ta AL LOUTEO I0 oo MORE GP ST REAM OF WELM

X NC9EYETVTCk Barr OM

SECON_A Ask BASIN WMK 50

L EL v+2r C h WER FL CF n6 wErA z9EFUl`SL1105S£c 9ETWLirrI r2 iIIWALL

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MAfkWJM FL5W IOi33a MOO

E L a5 41 a

•ODEAC PANF PL NcaMU ELLvJt OE MOO DETAIL T

MGa suu va 150

LI k Q I

EL MINIMUM FLOW 2495 MUD NOTES 1142av51

TWEM a 11426 1 All Concrete to be 4000psi 28 days EXtSTtNx 51rUCcUE 9Frna nott DETAft and 2 Contractor shall remove existing Walkway

Platform for installation of Weir Box

Contractor shall reinstall the Walkway and Platform

after installation of Weir Boi complete

IIrys Arrw°• Akcrki

SST 5tiC6N•ARf SETTLING POND IktFI•tih1ti l WEIKNSTPlI CY i PUNT CSYEEcP6WL1 PLANT SOUDHW STERN ELECTRIC POWER CC k0 6rvrrvCE LhE4 CCATE ScAa• O RED

9L • 2G7 RELEASCO Fos OVQTcc5 CNn For CANlrryc216N V •J FCX 04 WEIR FLOW CAPA I L1TY A `LL Lra7 RE LEASEC FpA CevNFrit9 CNe FM CI tree 9 a2 rqM W L4 q eayy n

oAMA 2 OR eT APP 5141 REV CESCRIF1ION DATE Ib+ 54 SVK0FLEE t1MbMEWA75 3 ON 9` WATEESTOP II11 xsfutf WEU r•NLL L OEEf ft NTO ENOr DIM boix OUIUU0Ul r iq•tiAFyx1Ef•Y•pY lx lUfFL10 EL 1145 1 4 1 1 4 5 0

41 I OW LT M SOII PACES L 340 •10 •I 10 R1A£t Stc1w EE

4 tTRS rx A34WIM ElEL 1141 340001 E L a T1 £olICtlMNWVS TIWElk E EL I I4E L 1 ••j4 ox 6C1 R7 ELI14 ci SECT10t HH 611453404

= 1=0 1145 S VsE I AL L •34E4 GCTRS Bow FACE5lV eo o 144 BIMBOFLEX 941E SI 02`955 ADWAL TIPICAL 50Th SIDES WALLL WAIERSTOP 4>J10145 IIIAF 4NLwmFLTAR 34 au 9 Uh0 BoT FALSLi OF W E 1R Hox ASIAt EIITI 1115o EL II96 wEtoll mcxtx4

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ow 9 LT PIS

1145dSECTION A S CVkON EE

SCALE I Ito m4 ON GCTR5 30B UALkwt tx d Lou CTRS

290 44 D oRSEr 11F C 0 441SEN6 tSut4ELSlxuCTUEE l+pqygpEn F60 Ai 100141041 ` l1` TIwuL EE nay o Dr EL 114SL TIWEVRR EL 114 L1G•Tl 0 340 I••0 LIM 11420 WlftfPnES C0Nt U SCALE14x4 QM81 8Sj S5 4YAA5gl J1

TFL004 EL II35 G f 4 4 t1R5 em WRNS 9EEP SOLES C4RSJ TAJ1t V OfEf HOLE _NLL 4 W 10 G CYItt1Wr I NSVriT 04 1l Q C3uF 17 Ml INO AUCxEE •1icr • •P1 veAMlTN EPoxy cAnvO IN 411144

SECTION FF D 9iotr fo nfi5 9t105 • rN 4 w _ MIM = •x SCALE 1 I o

SECTION SCALE I4 I0 INSTALL WE10 W F IU sN 1590E SIDES WIT 011T 51p> 14

11 BEVEL EbGF L SEE tETAIL• 6 Etr

001144 JJ WER W4l •1t O um L

0 II 1 L1R5 I5 9 `AATEfLSTOP 37 M M car A eu 11450 tir1 Ei 60TN 51035 ANO 001T9A5 f ELn45o E tlr •2Pl 9ii a M4U404 LTP aEVEL EDGE B` 0VlNLt4S 11 RED 6 INSTA44415511 DETAIL Ei II ta6 • I NO 6AP5 EL 11434 V I EL1141O •f1114 ttTe•ex4L SHLttltEkL I rEt0CE OF CLNC NOTN OUT rBEVEL EDGE FOR WEB

ww AI ExvyIw4 I •• ALL ELH5•6 F L •L40111 t14S pv p IG At

•6ox1t1R5 E C cTON CC WELD 51M50BOIICry r21 a G4P5 z A

•F i

ty• RANCER5 55001l01I Ct W41914 REQ r TI 1l JG Sr1000cG l0 SPACING Sw4 7•0 w1Ta4eo 10

DETAL 2 W 510 S OE1A55 SCnte 3 Ia

l50

SECTION llD •11EIIAR KAN AS SCALE14 10 AI IN•f SECON•PRY ASH SETTLINGPONS WEIR

i PI F fInY 1I SOWER 7 i Ill FLINT 0E 15 PLF I CO 1 SOUTHWESTERN ELECTRIC POWER KCTAUrtCo art BG1E D N0 Rt 4• 5 1E•EASFs FoA 1UOTES C5oRFmV 5rw611041 DR FCx lo4PC CNG A RELEASED FOR C6R04040 •NOI FOR 304 1iCTION 9z2XI I KP We 11ff ZEE 9t2 OESCRIprION DATE I OR I BY APP 210 I REV 1 of 6

AMERICAN ELECTRIC POWER

FLINT CREEK POWER PLANT

DESIGN CALCULATIONS

SECONDARY ASH SETTLING POND WEIR

OUTFALL 101

off o ARK REGs SEED I PHOY ESSJONAL LillG2Ns•L• eY r• •

7 z 2D0 2 of 6

Overview

The calculations shown are for the proposed new weir at Flint Creek Power Plants permitted Outfall 101 The Isco Channel Flow Open Measurement Handbook 6th Edition was used as a reference for the weir design

The crest elevation of the weir the the proposed is same as existing one so that the ponds normal surface elevation will not be affected The secondary ash ponds spillway will be raised by 2 feet to elevation

11450 to eliminate the over situation topping experienced during high rainfall events increasing the

by head and capacity of the weir

A compound weir was considered but flow near the transition zone will introduce error The weir

type is sharp crested rectangular with end contractions and to is designed adequately handle a 100 year 24 hour rainfall event

These improvements will flow provide greater capability and improved accuracy by slowing the approach velocity

FLINT CREEK SECONDARY ASH POND WEIR HEAD AND CAPACITY

120

Max Flow

e New Weir 100 r 24 rain y hr Old Weir

Normal F low

Max

Flow O ld Weir Min Flow 0

00 05 10 15 20 25 30

HEAD ft 3 of 6

1 Approximate rainfall runoff to basin

Watershed Area

in acres a= 835

runoff Typical coefficient for heavy soil p = 02

From Rainfall Atlas 100 24 hr rain Frequency yr is 875 inches

Actual extreme rainfall Climate Data Online NNDC for Siloam Springs weather

station is 91 inches

Use for 100 24 9 yr hr rain event

Rainfall inches in 8100 = 90

Million gallons per day based on rainfall water shed and runoff R100 MGD = a p 03259 = 40819 Results in 40819 MGD runoff to Sec Ash Pond 12

2 Consider flow from primary pond to secondary pond

Flow a 2 x 4 is through concrete submerged horizontal section 40 long Head differences from one pond to the other controls flow Note are and be stop logs in place can used to reduce flow to the secondary pond

Pri Pond elv 1144 = = 2 40 I Hpri height lent

elv Sec Pond 1 = 142 width = 4 1 Hsec kext =

Cross sectional area area = heightwidth = 8000

Assume Concrete friction factor f = 02

Derived from Bernoulli surface elv equation Using difference calculate velocity through section

Velocity is reasonable Using velocity and cross

sectional area flow is 2322 Hpri Hsec area = 32824930

Vc gpmc Vc74860

Lc f

ft 3 = 9142 = 4 MGDC = 144010 47268

Vc gpmc area + + sec kent kext

Therefore flow section from ash Pond Primary is

capable of flowing the 100 yr 24 hr rainfall

runoff to Sec Ash Pond 4of6

3 Use solve block to determine head on weir given crest length and maximum flow

Calculations are for rectangular weir with end contractions

Selected crest of weir feet 13 length in L =

Desired flow based on 100 24 hr rainfall + current outflow units of

yr in million Current outflow

gallons day is the 5 7 per typically in to MG

range Use 7 MGD as typical flow for calculations

Maximum design flow is MGD = 40819 + 7 = 47819

Initial guess head on the weir 05 xh =

Given

15 = MGD 2152L 02xhxh

Head Head = 1451 Findxh Head on weir Head 12 = 1742 inches

Check calculated gpm equals desired flow million in gallons per day

3 02HeadHead15 = gpm = 1495L 33219984 ifgpm 14410 > MGD OK Recalculate = OK

4 Determine overall dimensions of the approach channel

Approach channel dimensions are based on ratios to the maximum f low head units design in of feet The Isco Open Channel Flow Measurement Handbook 6th Edition was used as the reference

Dimensions are units

in of feet

Crest of weir length in feet L = 13000 iFL > 3FleadOK To Short OK

Measurement point of head DI = 4Head DI = 5805

Minimum crest height D2= 2Head D2 = 2903

Minimum end contraction D3 = 2Head D3 = 2903

Cross 5ection Depth 134= Head + D2 D4 = 4354

Approach Length to weir D5 = 20 Head D5 = 29025 5 of 6

5 Determine channel width using the cross section depth and an acceptable approach velocity

For the desired channel accuracy velocity is no more than 05 ftsec

Given

05 8Head VaPP Xb =

•Pm VaPP xbD474860

D6 = Findxb ifD6 > 8HeadOK To Short = OK D6 = 34002

D6 L Recalculate b3 based on D6 for acceptable velocity D3 = 10501 2 6 of 6

6 WEIR SUMMARY

DIMENSIONS ft FLOW

Head on weir Head = 1451 Million per day MGD = 47819

Crest of weir feet

length in L = 13000 Gallons per minute gpm = 33219984

Measurement upstream of weir DI = 5805 Velocity in channel = 0500 Vapp Minimum crest height D2 = 2903

Minimum end contraction D3 = 10501

Cross Section Depth D4 = 4354

Approach Length to weir D5 = 29025

Channel width D6 = 34002

Elevations Dimensions

Elevation top of weir plate 11426

Elevation bottom of channel 11396

Elevation of maximum expected head 114311716

Elevation of new spillway 11450 ETTL Engineers Consultants Inc GEOTECHNICAL _ MATERIALS _ ENVIRONMENTAL _ DRILLING _ LANDFILLS

August 18 2010

W Greg Carter PE American Electric Power 21797 SWEPCO Plant Road Gentry AR 72734

SUBJECT Flint Creek Power Station Existing Ash Storage Ponds Embankment Investigation Pittsburg Texas

Geotechnical Investigation ETTL Job No G3243

Dear Mr Carter

Submitted herein the report summarizingthe results a geotechnical investigation conducted

is of at the site the above referenced project

you have any questions concerning this report please contact us We are also available

If to perform any construction materials testing and inspection services that you may require

Thank you the opportunity service

for to be of

Sincerely

ETTL Engineers Consultants Inc

Robert M Duke Stephen R Richards PE Senior Project Manager Principal Consultant

August 18 2010

Distribution 2 AEP

210 Beech Street 1717 East Erwin 707 West Cotton Street

Texarkana AR 71854 Tyler Texas 75702 Longview Texas 75604 5505

8707720013 Phone 9035954421 Phone 903 758 0915 Phone

8702162413 Fax 903 595 6113 Fax 903758 8245 Fax

w w w e t t l i n c c o m Geotechnical Investigation

Flint Creek Power Station

Existing Ash Storage Ponds Embankment Investigation Gentry Arkansas

Submitted

American Electric Power Gentry Arkansas

Prepared

ETTL Engineers Consultants Inc

Tyler Texas

Revision 2 August 2010 EXECUTIVE SUMMARY

This Executive Summary provided a brief synopsis the specific recommendations and

is as of design criteria provided the attached report not intended a substitute a thorough

is in It as for reading the report entirety

of in its

Project Description

Evaluation the existing earthen embankments ash ponds the Flint Creek Power Station

of for the at Slope stability and seepage analyses the embankments were performed using information

for obtained from soil borings located the crest and downstream toe the embankments The

on of embankments the Primaryand Secondary Bottom Ash Ponds were investigated

for

Site Description

This investigation was conducted the Flint Creek Power Station embankments that are located

on at the plant which located 21797 SWEPCO Plant Road The power plant located the

is at is on northeast side the Reservoir and the ash ponds are located the south the plant the east

of to of on side the reservoir

Depth Number Borings

of Three borings were drilled feet deep the native soil level and four borings were drilled

to 30 at to 50 feet deep the crests the embankments The four deep borings were converted piezometers

in of to

Soils Encountered

The material the containment berm consists primarily stiff very stiff lean clay CL

fill in of to or fat clay CH with gravel and medium dense clayey gravel GC clayey sand SC with gravel

or overlying native soils which consist primarily weathered limestone with layers stiff hard lean

of of to clay CL with gravel The limestone encountered typically consisted solid layers less than

of 14 inches thick The Rock Quality Designation RQD the cores less than Atterberg

of is 25 Plasticity Indices tested soils ranged from 5 47

of the to

Groundwater Depth

Found range fromelevation 1119 1135 msl the open boreholes Groundwater anticipated

to to in is between the lake elevation 1140 and the primary and secondary pond elevations 1146

to be of of and 1143 respectively

Embankment Stability

The existing berm slopes are acceptable conditions aremaintained Aminimumfactor safety

if of 1.6 the long term was found the Secondary Ash Pond Rapid drawdown the level

of in on of of water the individual ponds lowers the predicted overall stability factors safety a minimum

in of to of 1.2 the PrimaryAsh Pond assuming ash the pond left against the slope

at no in

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page i TABLE OF CONTENTS

EXECUTIVE SUMMARY I INTRODUCTION 1

1.0 2.0 PROJECT DESCRIPTION 1 SITE DESCRIPTION 2

3.0 4.0 FOUNDATION STRATIGRAPHY PROPERTIES 2 SURFACEWATER 2

4.1 CHARACTERISTICS 4.2 REGIONAL GEOLOGY 2 4.2.1 Stratigraphy and Structure 2 4.2.2 Boone Formation 2

4.2 GEOLOGIC PROCESSES 3

4.2.1 Fault Systems and Structural Processes 3

4.2.1.1 Seismic Design Parameters 3 4.2.1.2 Liquefaction 3 4.2.2 Erosional Processes 4 4.3 SOIL STRATIGRAPHY 4 GROUNDWATER 4 5.0 OBSERVATIONS 5.1 PIEZOMETERS 4 EMBANKMENT SEEPAGE STUDIES 5

5.2 5.2.1 Seepage Losses and Pressures 5 6.0 POND EMBANKMENT SECTIONS 6 6.1 SLOPE STABILITY ANALYSIS 6 6.2 SLOPE PROTECTION 8 7.0 EMBANKMENT MONITORING 8 8.0 LIMITATIONS 8

10 APPENDIXI 0 FIELD OPERATIONS

10 0 LABORATORY II TESTING 10 Plate I Plan Borings

of Plate 2 Site Surface Geology Logs Borings with Laboratory Test Data

of Seepage Results

Slope Stability Results Test Results Arkansas Water Well Reports

Key Soil Classification Symbols

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page

ii INTRODUCTION

1.0 This study was performed the request and authorization proceed granted byGreg Carter PE

at to with AEP Hallsville Texas accordance with our proposal dated October 13 2009 Field

in operations were conducted November though November 2009

on 3rd 6th

The purpose this investigation was define and evaluate the general subsurface conditions

of to for the primary and secondary ash ponds the Flint Creek Power Plant Gentry Arkansas

at in Specifically study was planned determine following

the to the

_ Subsurface stratigraphy within the limits exploratory borings

_ Classification strength and permeability characteristics the embankment and

of foundation soils and

_ Slope stability and seepage the existing embankments

determine this information a variety tests were performed the soil and ash samples The

To of on scope testing this report comprised Standard Penetration Atterberg liquid and plastic limits

of for Percentage Fines Passing the No 200 sieve and Natural Moisture Content Unconsolidated

of Undrained Triaxial tests and Permeability These tests were conducted classify soil strata

to the according a widely used engineering classification systemidentify and provide quantitative data

to soils define shear strength characteristics define seepage characteristics and determine the

for slope stability the existing embankments

The conclusions and recommendations that follow are based limited information regarding site

on topography provided ETTL others Should any portion this information prove incorrect this

to by of firmshould notified order assess the need revisions this report Borings were drilled

be in to for to at locations based a site plan provided the client

on by

PROJECT DESCRIPTION

2.0 This project entails the evaluation the existing earthen embankments the Flint Creek Power

of at Station Slope stability and seepage analyses the embankments was performed using

for information obtained from soil borings located the crest and outside toe the embankments

on of The embankments the Primaryand Secondary ash ponds were evaluated

for

One seepage and one stability analyses was conducted each pond Table 2.0 below lists the

for number borings and depths each pond well the piezometers installed

of for as as

Table 2.0 Boring and Piezometer Depths and Locations Pond Boring Numbers Depths Piezometer Numbers and Depths B3 – feet deep B3 – feet deep

37 37 PrimaryAsh Pond B4 – feet deep B4 – feet deep

50 50 B5 – feet deep

30 B1 – feet deep 48 B1 – feet deep B2 – feet deep 48 Secondary Ash Pond 50 B2 – feet deep B6 – feet deep 50

23 B7 – feet deep

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page 1 SITE DESCRIPTION

3.0 This investigation was conducted the Flint Creek Power Station embankments that are located

on throughout the plant which located 21797 SWEPCO Plant Road The Ash ponds are located

is at south the plant and east the reservoir See the Plans Borings the locations the

of of of for of embankments investigated

4.0 FOUNDATION STRATIGRAPHY PROPERTIES

Regional local and sitespecific environmental characteristics have been identified reviewof the

by surface subsurface and groundwater data gathered during the course this study

4.1 Surface Water Characteristics

The site situated a topographically level feature with a slight slope from northeast

is on to southwest The surface elevation study site 1100 1160 feet above mean sea level msl

of the is to

Little Flint Creek enters the subject site along the western portion the property and flows into the

of reservoir The ash ponds are located unnamed tributary that flows along the south side the

on an of property into the reservoir Surface water runoff from the site expected move the southwest

is to to along Little Flint Creek

Regional Geology

4.2 4.2.1 Stratigraphy and Structure

The State Arkansas can divided geologically into two general areas nearly equal size The

of be of northwestern half part a physiographic division that known the Interior Highlands and the

is of is as southeastern half part the Gulf Coastal Plain The rocks the highland area are dominated

is of in by welllithified sandstones shales limestones and dolostones Paleozoic age The rocks the

of of Ozarks slightly the south and have a dendritic drainage pattern Since shales and siltstones

tilt to erode faster than sandstones and limestones the basic topography flat topped mountains with

is stepped flanks contrast the topographic expression the Ouachitas the south controlled

By of to is only erosional resistance the rocks also their internal structure The strata are

not by the of but by complexly folded and frequently faulted The mountains are mostly eastwesttrending ridges supported erosionally resistant rocks and separated less resistant rocks

by by

4.2.2 Boone Formation The Boone Formation outcrops the study site The Boone Formation predominately lower

at is Mississippian age The overlying soils are the Bodine Series which vary thickness from

in of in 10 feet feet These soils were developed residuum fromvery cherty limestones strong

to 50 in on to steep slopes The soils are coarser textured and more yellow than the Baxter soils also more cherty general they may described brown reddish brown brownish yellow clay silty

In be as to to and very cherty The high content chert a major factor the soils and tends obscure other

of is of to morphology

The Boone Formation described a cherty limestone consisting beds chert and thin

is as of of to massively bedded limestone which vary character lateral extent The Boone can

in in be distinguished presence chert which seen the exposures the subsurface cores The

by of is in or in Chert beds cover most the slopes and valley floors

When first exposed the chert compact and a light gray color weathering may become

is On it yellowish brown from iron staining fragmental light and porous also many diverse colors may

It occur concretions limestone beds lenses and massive beds The Boone has

as in as as considerable silica these beds and upon removal the lime solution the remaining rock has a

in of by porous texture This also referred “Cripoli” Some the limestone beds are charged with

is to as of

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page 2 bituminous matter which gives odor when broken and exhibit a dark residue appearing

off an as dried asphalt

Solution waters create some caves and voids throughout the Boone and not uncommon

is it to penetrate a void while drilling this formation

this area Little Flint Creek the thickness Boone could much 350 feet believed

In of of be as as It is that none the borings this investigation penetrated any formation older than the Boone

of in

4.2 Geologic Processes

4.2.1 Fault Systems and Structural Processes

The project site was examined the presence faulting reviewing available literature maps

for of by and site reconnaissance addition the examination the subsurface boring data the site

in to of for

There are minor faults running northeast and southwest approximately two five miles either

to in direction this site Structures that formed the flank the Ozark dome the late Paleozoic

of on of of

Ouachita orogeny are identified monoclinal folds that displace the generally flat lying Boone

as Formation Both east striking normal faults and broader northeast striking dextral strikeslip fault zones probably reflect Pennsylvanian Early Permian deformation the developing Ouachita

of orogeny The caves and voids throughout the Boone mentioned above can also produce localized sinkholes

4.2.1.1 Seismic Design Parameters

Data regarding soil type and density a depth 100 feet needed designate a design class

to of is to for the profile where liquefaction potential not considered However predict that the site could

is we be classified Class D based the limited data available

A seismic impact zone area with a percent greater probability that the maximum

is an 10 or horizontal acceleration rock expressed a percentage the earth’s gravitational pull will

in as of exceed 0.10g years

in 50

Based the maps and the site coefficients determined site class C contained IBC

on for in the parameters listed below are recommended the Code

as by

Site Coefficients 1.60

Fa 2.40

Maximum Earthquake Spectral Response Acceleration Parameters SMS 0.217 SM1 0.139

Design Spectral Response Acceleration Parameters SDS 0.144

SD1 0.093 Note Acceleration used seismic evaluation

for

4.2.1.2 Liquefaction

Liquefaction a phenomenon where soil pore pressure builds rapidly during cyclic loading

is up causing a loss shear strength and consequent significant ground movement both laterally and

of vertically layman’s terms the soil turns into quick sand losing ability support load and can

In to spread laterally out from under foundations Foundations sitting sand that liquefies during

on an earthquake can sink into the soil

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page 3 2 Recent research1 has shown that liquefaction potential exists not only relatively clean sands but

in also under certain circumstances sands silts and clayey soils low plasticity PI

in of 12 or up to 20 MC0.85Liquid Limit with significant fines content order liquefaction triggered the

if In for to be water content finer soils needs high generally 8085 the Liquid Limit and the density

of to be of relatively low assessed terms the SPT blow count generally where SPT Value normalized

in of N1 overburden pressure low addition the frequency andmagnitude ground shaking has

for is In of to reach a certain threshold which related the soil properties and local geology

is to

The native soils are predominantly clayey gravel GC and lean claywith gravel CL over limestone

These characteristics taken together with the fact that the site a zone relatively lowmaximum

is of in ground acceleration indicate a negligible risk liquefaction

4.2.2 Erosional Processes

Erosional processes the area study are limited those produced the drainage systems

in of to by of

Little Flint Creek Due the geology and the gentle relief the site topography erosion isminimal

to of

4.3 Soil Stratigraphy

Detailed the attached boring logs are the specific types and depths the various soil strata

on of encountered The logs show defined boundaries between various soil types but reality the

in transition between types generally gradual

The material the containment berm consists primarily stiff very stiff lean clay CL

fill in of to or fat clay CH with gravel and medium dense clayey gravel GC clayey sand SC with gravel

or overlying native soils which consist primarily weathered limestone with layers stiff hard lean

of of to clay CL with gravel The limestone encountered typically consisted solid layers less than

of 14 inches thick The Rock Quality Designation RQD the cores less than 25 Atterberg

of is Plasticity Indices the tested soils ranged from 5 47

of to

GROUNDWATER OBSERVATIONS

5.0 Groundwater was measured each boring location during drilling operations and four piezometers

at were installed Two new piezometers were installed each embankment the Primaryand

on for Secondary ash ponds Groundwater levels the piezometers have not been measured date

in to Groundwater was found range from elevation 1119 1135 msl the open boreholes

to to in Groundwater anticipated between the lake elevation 1140 and the primaryand secondary

is to be of pond elevations 1146 and 1143 respectively

should noted however that seasonal groundwater conditions might vary throughout the year

It be depending upon prevailing climatic conditions Thismagnitude variance will largely dependent

of be upon the fluctuation pond and lake levels

5.1 Piezometers

Four piezometers were installed the two embankments the site These piezometers will

for at be used monitor the water level the embankments Piezometers were installed the boring

to in in locations selected AEP prior the site work The piezometers are numbered based the

by to on

1 Idriss IM and Boulanger RW Semi Empirical Procedures Evaluating Liquefaction Potential During

for Earthquakes Invited Paper 11th International Conference Soil Dynamics and Earthquake Engineering Berkley

on CA January 2004

2 Seed R B Recent Advances Soil Liquefaction Engineering A Unified and Consistent Framework 26th

et al in Annual ASCE Los Angeles Spring Seminar April 2003

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page 4 boring number where each was installed i e B1 was installed boring location B1 Copies

at of the Well Logs and State Arkansas Well Reports may found the Appendix

of be in

Upon completion drilling activities the geotechnical borings the piezometers were installed

of for in the open borehole the depth approximating the natural ground level the boring was deeper

to If than the depth proposed screening the boring was backfilled with bentonite the appropriate

of to depth The 2inch piezometer was installed within the open borehole along with a 1inch PVC pipe Fresh water was pumped within the 1inch PVC pipe until the water flowing back from the bottom

of the borehole the surface had thinned The piezometers were constructed schedule 40 2inch

to of diameter PVC pipe consisting new box wrapped flushjoint threaded screen 0.010 inch mill

of slot and casing This installation depth should measure the final groundwater elevation after the water through the embankment has stabilized This depth predicted the seepage analyses

is the by below

The filter pack materialplaced around the well screen consisted 20 silica sand The filter pack

of 40 sand was gravity placed into the annular space around screen between the well and the

the borehole wall Filter pack material was poured until the top the filter pack extended two 2 feet

of above the top the screen Material thickness the annular space was verified using a weighted

of in fiberglass measuring tape through the use a 1inch PVC pipe The top the filter pack was

or of of then sealed with bentonite pellets which were allowed gravity flow into the annular space a

to to minimum thickness two 2 feet The bentonite seal was hydrated with water An additional

of bentonite seal was placed within the remaining portion the annular seal the surface The

of to piezometers were protected with flush mount surface completions

Embankment Seepage Studies

5.2 5.2.1 Seepage Losses and Pressures

The anticipated water level due seepage through the embankments was investigated based

to on the high water level anticipated each individual pond using the computer program SEEP

in 2D by Environmental Modeling Systems Incorporated The seepage both through the embankment and through the foundation soils each embankment location was estimated based the permeability

at on tests soils encountered the site The permeabilities representative samples the soil

of at of of 8 9 ranged from x cmsec x cmsec test results included the Appendix

2.4 10 to 9.4 10 in Permeabilities the weathered rock layers were not tested but due the possibility

of to of interconnected voids permeabilities the rock mass could vary widely estimated published

of in 3 8 literature this kind geology range from1 x cmsec 1 x cmsec We understand

for of to 10 to 10 that grout curtains that were installed around the perimeter keep the reservoir filled a useable

to to level This fact substantiates existence significant interconnected voids rock mass

the of in the Due the high plasticity the soil interlayered with rock seams we anticipate that the

to of permeabilities the soil seams will similar those the surficial clays tested Based the

of be to of on possibility gravel seams the well the native soils flows were also calculated

of in fill as as in by 8 increasing the average flow rate i e increasing the permeability a factor ie 1 x

by of 10 10 7 cmsec would become 1 x 10 cmsec

Seepage losses the highest permeability predicted the embankments are predicted 0.03

for for at gallon day gpd per foot dam length based the assumptions above which not account

per of on do significant seepage losses the voids the rock mass

for in in

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page 5 Table 5.2.1.1 –Permeability Test Results Boring Depth Unit Weight pcf Permeability cmsec 8 B1 18’ 20’ 125.1 1.5 x

10 8 B1 35’ 130.5 1.5 x 33’ 10 9 B2 129.6 9.4 x 8’ 10’ 10 8 B2 23’ – 25’ 131.3 2.4 x

10 8 B7 – 127.1 2.0 x

5’ 7’ 10

Table 5.2.1.2 –Embankment Seepage Rates Seepage Rates Cubic Feet per Day per Foot Embankment MaxMin 3 4 PrimaryAsh Pond 4 x 5 x

10 10 3 4 Secondary Ash Pond 4 x 1 x

10 10

The water levels piezometers are predicted reach slightly above the average the

at the to of upstream pond and downstream lake normal pool elevations Water levels approaching the pond level could indicate a seepage pressure not anticipated this design Levels found within 1

in to be foot the pond levels should brought the attention ETTL additional study

of be to of for

6.0 POND EMBANKMENT SECTIONS

The berm heights ranged from feet the Secondary Ash Pond a maximum around feet

35 for to of 46 the PrimaryAsh Pond

for

6.1 Slope Stability Analysis

embankment slopes must stable with respect shear failure through the embankment and

All be to or the foundation strata The existing slopes are standing and have been doing approximately

so for years with obvious slope failures Therefore slopes must have a Factor Safety

or 30 no all of at above 1 under current conditions However according the Corps Engineers the Factor

to of of Safety long termstability should a minimum 1.5 new construction Older dams with a

for be of for all long history may less but this study a minimum 1.5 was still utilized This study was

be for of conducted assure that the embankments meet the minimumSafety Factors

Slope stability was evaluated using the computer program Geostase developed Gregory

by Geotechnical Software Geostase the latest version GSTABL7 and has not been released

is of generally yet The program capable calculating the factor safety potential failure

is of of for surfaces using several different methods The analyses this project were conducted using the

for modified Bishop method this was believed most appropriate approach The program

as to be the has automatic search routine determining the minimum factor safety The resulting

an for of analyses are depicted graphically and are included the Appendix

The surveyed boring elevations were used embankment top elevation and the original

for an topographical maps along with the construction plans the embankments were used order

for in to determine cross sections the stability analyses

for

What was believed the “worst case” embankment cross section based visual observations

to be on during the initial site visit was used the analysis The tallest section was chosen The soil

in strengths were modeled using percent strength test values determined fromtesting where

85 of the

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page 6 a test was conducted Where triaxial test was conducted average strength values the and

no of fill native soils were used based the soil types well correlations with SPT blow counts These

on as as average results were also reduced percent Reductions 15 were used attempt

by 15 of in an to accommodate potential variations the soil well compensate the limited amount data

in as as to for of Due the amount gravel the samples only three triaxial tests were possible The original

to of in embankment subgrade was assumed gravel and not solid rock based the poor recovery

to be on RQD the thin layers accrual rock cored and significant clay seams found the samples 25 of in Based the rounded edges the surficial native soils are gravel a clay matrix We have

on in assumed that these subgrade soils extend deeper than first layer solid rock encountered since

of the rock seams were still thin most locations and order use a more conservative basis

in in to for analysis Results the Triaxial tests summarized Table 6.1.1 below The rock mass

of are in strength was determined using the strength the cores tested and the computer program RocLab

of from Rockscience This program predicts the strength entire rock mass based the

1.0 of the on Hoek Brown criterion and backcalculates a cohesion and friction angle the rock mass The test

for results are included Appendix

in the

Table 6.1.1 Summary Soil Test Results

Effective Stress Total Stress Fill Soil

or Parameters Parameters Boring Depth Native Classification

Friction Cohesion Friction Cohesion Angle psf Angle psf

B2 37 Fill CH 33.7 0 15.9 345

B2 2335 Native CL 33.0 18.3 275

B3 Fill CL 24.0 460 14.1 575 3 7’

Native B1 38.5 1000 38.5 1000 43’ Rock LS

Three cases were analyzed each slope steady state long termsteady state with seismic loads

for and rapid drawdown water the ash ponds the rapid drawdown study the water the

of the in In in ash ponds removed but the water level the embankment remains For the evaluation

is in of steady state conditions the soils were evaluated using effective stress parameters For the rapid drawdown case the slopes were evaluated using total stress parameters Graphical representations

the slope stability results are included the Appendix Results the analysis are summarized

of in of Table 6.1.2 below

Table 6.1.2 Slope Stability Analyses Results

Steady State with Steady State Rapid Drawdown Pond Seismic Factor Factor Safety of Factor Safety of Safety of

PrimaryAsh Pond 1.9 1.3 1.2

Secondary Ash Pond 1.6 1.2 1.5

should noted that due the karst nature the rock the site factors other than those

It be to of at considered this analysis may affect the stability the slopes question Solution cavities

in of in of varying sizes characterize this geology was not possible within the limited scope this

It of

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page 7 investigation map cavities Consequently cavities were assumed present However

to no to be no significant cavities were encountered any the borings this study other than vuggy rock

in of of In addition strength obtained from compression testing solid rock cores was reduced

the of significantly using the GSI approach attempt predict the strength vuggy rock used the

in an to of in analysis

6.2 Slope Protection

Earthen embankment slopes require some form protection fromexcessive erosion A good cover

of approved grasses should provide adequate slope protection The embankments appeared

of to have adequate vegetation some the locations had been recently cleared trees Bushes

but of of and trees two feet more height are not considered satisfactory slope protection because

of or in of the harmful effect grass and the hazards tree roots

on of

A routine and periodic maintenance program should implemented prevent excessive growth

be to Animal control should also considered integral part routine embankment maintenance

be an of

EMBANKMENT MONITORING

7.0 Visual drive inspections and cursory on foot inspections should performed accordance with

by be in AEP requirements a minimum dam safety inspections should conducted biannually

As be

Should any unusual occurrences noted connection with the operation the dams either a

be in of as result the cursory drive inspections the result the detailed damsafety inspections AEP

of by or as of Geotechnical Engineering and ETTL Engineers Consultants Inc should immediately notified

be evaluation and development necessary a Remedial Action Plan

for if of

8.0 LIMITATIONS

Geotechnical design work characterized the presence a calculated risk that soil and

is by of groundwater conditions may not have been fully revealed the exploratory borings This risk

by derives from the practical necessity basing interpretations and design conclusions a limited

of on sampling the subsoil stratigraphy the project site The number borings and spacing

of at of is chosen such a manner decrease possibility undiscovered anomalies while

in as to the of considering the nature loading size and cost the project The recommendations given this

of of in report are based upon the conditions that existed the boring locations the time they were

at at drilled The term existing groundline existing subgrade refers the ground elevations and soil

or to conditions the time our field operations

at of

conceivable that soil conditions throughout the site may vary from those observed the

is It in exploratory borings such discontinuities exist theymay not become evident until construction

If do begins possibly much later Consequently careful observations geotechnical engineer

or by the must made the construction progresses help detect significant and obvious deviations

be of as it to actual conditions throughout the project area from those inferred from exploratory borings

of the Should any conditions variance with those noted this report encountered during

at in be construction this office should notified immediately that further investigations and

be so supplemental recommendations can made

This company not responsible the conclusions opinions recommendationsmade others

is for or by based the contents this report The recommendations made this report are applicable only

on of in the proposed scope work defined SECTION 2.0 PROJECT DESCRIPTION and maynot

to of as in

used any other work without the express written consent ETTL Engineers The purpose

be for of of

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page 8 this study only stated elsewhere herein and not intended comply with the requirements

is as is to of TAC 330 Subchapter T regarding testing determine the presence a landfill Our

30 to of professional services have been performed our findings obtained and our recommendations prepared accordance with generally accepted geotechnical engineering principles and practices

in warranties are either expressed implied

No or

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page 9 APPENDIX

I 0 FIELD OPERATIONS Subsurface conditions were defined 7 sample core borings drilled depths ranging from

by to 30 to

feet and ETTL personnel drilled borings locations selected based a site visit

50 the at on in conjunction with the client Field boring logs were prepared drilling and sampling progressed

as The final boring logs are also included Appendix Descriptive terms and symbols used the

in the on logs are accordance with the Unified Soil Classification System ASTMD 2487 A reference key

in provided the final page this report

is on of

Truck and track mounted drill rigsutilizing dry auger drilling procedures were used advance the

to borings Samples were continuous the upper feet and 5 feet intervals below feet

at in 10 at 10 or major strata changes Soilswere sampled bymeans a 1 38inch ID 24 inch long split spoon

of by sampler driven into the bottom the borehole accordance with ASTM D 1586 procedures

of in In conjunction with this sampling technique the Standard Penetration Test was conducted

by recording the Nvalue which the number blows required a 140pound weight falling

is of by 30 inches drive a split spoon sampler 1 foot into the ground For very dense strata the number

to of blows limited a maximum blows within a 6inch increment Where possible the sampler

is to of 50 seated inches before value determined The value obtained from the Standard

is six the N is N Penetration Test provides approximate measure the relative density which correlates with the

an of shear strength soil The disturbed samples were removed from the sampler logged packaged

of and transported the laboratory further identification and classification

to for

Soils were sampled means a 3inch OD 24 inch long thick walled Shelby Tube sampler

by of by

Using the drilling rig's hydraulic pressure the sampler was pushed smoothly into the bottom the

of borehole The consistency these samples was measured the field a calibrated pocket

of in by penetrometer These values recorded tons per square foot are shown the boring logs Such

in on samples were extruded the field logged sealed maintain situ conditions and packaged

in to in for transport the laboratory

boreholes were backfilled with grout after collecting final groundwater readings Samples

All obtained during our field studies and not consumed laboratory testing procedures retained

by will be our Tyler office free charge a period days arrange storage beyond this point

in of for of 60 To in time please contact the Tyler office

0 LABORATORY TESTING

II Upon return the laboratory a geotechnical engineer visually examined samples and several

to all specimens were selected representative identification the substrata determining the

for of By Atterberg liquid and plastic limits ASTMD 4318 and percentage fines passing the No 200 sieve

of ASTM D 1140 field classification the various strata was verified Also conducted were natural

of moisture content tests ASTM D 2216

Size distribution several soil samples was determined using a Hydrometer test ASTM D 422

of Permeabilities ASTM D 5084 were also performed a representative samples

Strength characteristics the cohesive substrata were evaluated conducting unconsolidated

of by undrained triaxial compression tests ASTMD 2850 selected undisturbed field samples obtained

on with the Shelby tube sampler Direct Shear tests ASTM D 3080 were performed undisturbed

on samples retrieved during drilling operations The results these tests are either presented the

of in individual boring provided this Appendix a separate result behind logs the

log of in or as the in Appendix

ETTL Engineers Consultants Flint Creek Power Station Embankment Study Gentry Arkansas

Geotechnical Investigation ETTL Job No G3243

09 Page

10 ETTL APPROVED BY FLINT CREEK PLATE 1 PLAN OF BORINGS E477 JENGINEERS Sc CONSULTANTS POWER PLANT JOB NO G324309 MAIN OFFICE DRAWN BY 1717 Edt Erin GENTRY ARKANSAS 2010 KCR D7 5904621 DATE JAN SCALE NTS

T9 Flint Creek Power Station Gentry Arkansas

Primary Ash Pond Steady State

ETTLSGeotechEngineers2009 GeCootencshunlticaanltJsoIbncF iles 3243 AEP Flint Creek Power Plant Bottom Ash Ponds Geo Stability Analysis Slope StabilityPrimary

09 SS in

1250 1250 No Soil Soil Moist c Pconst Piez Surf

FS Wt Sat Wt Phi ru

1 Desc pcf pcf psf deg ratio psf

1.9 No No 2 1 129.0 134.0 390.0 20.4 0.00 1

2.0 Fill 0.0 3 2 Native Soil 130.0 133.0 75.0 28.1 0.00 1

2.0 0.0 4 3 Native Rock 148.0 148.0 865.0 35.0 0.00 1

2.0 0.0 5

2.0 1200 6 1200

2.0

2.0 8

2.0 2 3 1 8 6 4 5 7 9

9 10

2.0

10 2.0

B3 S1 1 1 1150 1 1 1150

B2 B4 S1

B5 B6 B10 B1 B9 S2 S2 B7 B8 S2

S2 S2 S2 S2 1100 B11 1100 S3

1050 1050

1000 1000 0 50 100 150 200 250 300 350 400 GEOSTASE FSmin 1.9

Modified Bishop Method

PLATE P1 i•ri•lgs r MDcp

r 1 lIS 3SSC • 83za

JR r` t L Oc c ` •

C tli

OZARK REGION

Alluvium sad terrace deposheAlluvial deposits of pre

sent streams and on one or more terrace Js

GraeelGravel mt Isolated hill within 40 miles 64 km

nl the Mon so ppl Embe ersent Many small deposits to

the wont not shown

1 Cretaceous racks

Ns Stnka Formation

wnr Grove Member of the Hale Bloyd Si and prairie

Ph Cane Hill Member of the Hale Formation

m me 1 ipfG lItkin Limestone hayetteetne J ong Batesville SW Wediagton Sandstone Member end

atone llncioding the Hindtille Limestone Member

Chattanooga Shale Lower Minslaaippian and Upper

Devonian Cliry LimeswneMiddle Devoninnh and

Penn en in Lower Devonian

Limestones Lafferty St Clair and BrasofeM

Cason Shale and Fernvale Limestone Upper OsdooL an and Kimmawick Limestone Piston Limestone

and Jaac hire Dolomite Middle Ordovician

Ose St Peter Sandstone and Eeerten Formation Middle

firdovlclan

On Poston Dolomite

Oslo Cotter and Jefferson City Daionotes

10 0 10 20 30 MILES

10 0 10 20 30 40 50 KILOMETERS

NATIONAL GEODETIC VERTICAL DATUM OF 1929

ETTL GEOLOGIC JOB NO 6324309 ENGINEERS SITE MAP OF II CONSULTANTS SURFACE DATE 1993 ARKANSAS MAIN OFFICE 1717 Eaat Erwin

Tecan 75702 GEOLOGY Tyler SCALE u 903 5950021 1500000 LOG OF BORING B1 DATE 11 309 ETTL PROJECT Flint Creek Power Plant SURFACE ELEVATION ENGINEERS 1154.8 Gentry Arkansas CONSULTANTS ATTERBERG PROJECT NO G3243 09 BORING TYPE Flight Auger LIMITS

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

PI 0 20 60 GC

CLAYEY GRAVEL GC red and tan P3.5

P1.5 40Sieve 61

13 30 16 14

32 4 Sieve 55

dense N 43

red tan and white

medium dense 40Sieve

N 17 11 30 16 14 71

23 4 Sieve 62 10

N 25

native soil

gray tan and red moist P2.5 28 40Sieve 64

12 43 16 27 4 Sieve 56

CL LEAN CLAY CL red and tan saturated P4.5

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.00 W 9431.496 Water Observations Seepage 23 while drilling Water level P Pocket Penetrometer tsf 23 and open 39 upon completion and after 30 minutes

to T Torvane tsf

L Lab Vane Shear tsf LOG OF BORING B1 DATE 11 309 ETTL PROJECT Flint Creek Power Plant SURFACE ELEVATION ENGINEERS 1154.8 Gentry Arkansas CONSULTANTS ATTERBERG PROJECT NO G3243 09 BORING TYPE Flight Auger LIMITS

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

20 60

CH SANDY FAT CLAY CH hard red and tan P4.5 17 50 20 30 54 40Sieve 40 with gravel 4 Sieve 34

CL LEAN CLAY CL very stiff red and tan P2.5

CL LEAN CLAY WITH SAND CL very stiff red P3.5 30 41 18 23 83 40Sieve 7 and gray 4 Sieve 0 40

LIMESTONE moderately strong limestone 151 326.00 0 seams 16 gray crystalline clay thick

45 bedded fresh unfeatured RQD 0.25

Bottom Boring 48

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.00 W 9431.496 Water Observations Seepage 23 while drilling Water level P Pocket Penetrometer tsf 23 and open 39 upon completion and after 30 minutes

to T Torvane tsf

L Lab Vane Shear tsf LOG OF BORING B2 DATE 11 309 ETTL PROJECT Flint Creek Power Plant SURFACE ELEVATION ENGINEERS 1155.1 Gentry Arkansas CONSULTANTS ATTERBERG PROJECT NO G3243 09 BORING TYPE Flight Auger LIMITS

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

PI 0 20 60 GC

CLAYEY GRAVEL GCmedium dense red N 18 14 44 20 24 40 40Sieve 52 and tan with gravel 4 Sieve 42

CH FAT CLAY WITH SAND CH stiff red and tan P4.5 40 Sieve 30 61 26 35 7

80 4 Sieve 2

P2.0

GC CLAYEY GRAVEL GCmedium dense red 3.5 40Sieve P 15 62 18 44 49

47 and tan with sand and gravel 4 Sieve 37 10

CL SANDY LEAN CLAY CL red and tan with gravel

GC CLAYEY GRAVEL GCmedium dense red P2.0 13 40Sieve 81

12 38 15 23 and tan moist 4 Sieve 76

20 native soil

CL SANDY LEAN CLAY CL very stiff red and P3.0 tan with gravel

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.025 W 9431.467 Water Observations Seepage 20 while drilling Water level P Pocket Penetrometer tsf 20 and open upon completion and after 1 hour T Torvane tsf

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

20 60

P3.5 19 45 17 28 60 40Sieve 35 4 Sieve 28

P3.9

LIMESTONE 14 thick layer

LIMESTONE 8 thick limestone ledge

SF 24 53 22 31 7 40Sieve 92 4 Sieve 86

N 50 0.5

45 rock cuttings RQD 0.25 171.00 0

solid rock seam 48 148

50 Bottom Boring 50

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.025 W 9431.467 Water Observations Seepage 20 while drilling Water level P Pocket Penetrometer tsf 20 and open upon completion and after 1 hour T Torvane tsf

L Lab Vane Shear tsf LOG OF BORING B3 DATE 11 409 ETTL PROJECT Flint Creek Power Plant SURFACE ELEVATION ENGINEERS 1154.7 Gentry Arkansas CONSULTANTS ATTERBERG PROJECT NO G3243 09 BORING TYPE Flight Auger LIMITS

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

PI 0 20 60 CL

SANDY LEAN CLAY CL very stiff gray and N 19 tan with gravel

brown and red with gravel P2.0 40Sieve 23

20 37 15 22

63 4 Sieve 18

gray and tan with gravel P1.6

CH SANDY FAT CLAY CH stiff tan and red 40Sieve N 11 19 64 17 47 28

57 with gravel 4 Sieve 19 10

very stiff

N 27

GC CLAYEY GRAVEL GCmedium dense gray N 9 42 40Sieve 51

19 27 18 22 and tan with gravel 4 Sieve 37

20 native soil

brown 40Sieve

13 30 17 13 39 54 4 Sieve 42

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.116 W 9431.449 Water Observations Dry and open 31 upon completion

to P Pocket Penetrometer tsf

T Torvane tsf

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

20 60

LIMESTONE rock cuttings

30 RQD 0.25

P4.0

LIMESTONE

RQD 0.25

Bottom Boring 37

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.116 W 9431.449 Water Observations Dry and open 31 upon completion

to P Pocket Penetrometer tsf

T Torvane tsf

L Lab Vane Shear tsf LOG OF BORING B4 DATE 11 409 ETTL PROJECT Flint Creek Power Plant SURFACE ELEVATION ENGINEERS 1154.9 Gentry Arkansas CONSULTANTS ATTERBERG PROJECT NO G3243 09 BORING TYPE Flight Auger LIMITS

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

PI 0 20 60 CL

SANDY LEAN CLAY CL stiff tan and gray N 8 20 40 17 23 52 40Sieve 42 with gravel 4 Sieve 30 N

5 GC CLAYEY GRAVEL GCmedium dense tan N 22 40Sieve 71

13 10 48 20 28 and red 4 Sieve 62

CL LEAN CLAY WITH GRAVEL CL stiff red P1.5

and tan 10

reddish brown and tan 4.5 40Sieve P 21 28 16 12 44

51 4 Sieve 31

CL SANDY LEAN CLAY CL very stiff tan and N

21 gray with gravel

20 native soil

GC CLAYEY GRAVEL GCmedium dense tan 9 40Sieve N 18 45 20 25 38 55 and red with gravel 4 Sieve 45

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.149 W 9431.463 Water Observations Dry and open 36 upon completion and

to P Pocket Penetrometer tsf after minutes

30 T Torvane tsf

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

20 60

CL SANDY LEAN CLAY CL very stiff tan red N 19 and gray with gravel

GC CLAYEY GRAVEL GCloose tan gray and N 8 red saturated

CL SANDY LEAN CLAY CL very stiff tan gray N 18 18 43 1627 60 40Sieve 32 and red with gravel 4 Sieve 25

soft N 5

GP GRAVEL GP white 45

CL SANDY LEAN CLAY CL stiff red with N 10 gravel

50 Bottom Boring 50

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.149 W 9431.463 Water Observations Dry and open 36 upon completion and

to P Pocket Penetrometer tsf after minutes

30 T Torvane tsf

L Lab Vane Shear tsf LOG OF BORING B5 DATE 11 509 ETTL PROJECT Flint Creek Power Plant SURFACE ELEVATION ENGINEERS 1142.6 Gentry Arkansas CONSULTANTS ATTERBERG PROJECT NO G3243 09 BORING TYPE Flight Auger LIMITS

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

PI 0 20 60 GC

CLAYEY GRAVEL GC very dense red and N 62 white

dense N 40Sieve 55

39 32 53 25 28

41 4 Sieve 41

5 GP POORLY GRADED GRAVEL GP very N

71 dense white with limestone gravel

very dense 502 4 40Sieve N 20 95 4 Sieve 76 10

N 40

N 26

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.176 W 9431.492 Water Observations Dry and open 20 upon completion and

to P Pocket Penetrometer tsf after minutes

30 T Torvane tsf

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

20 60

no recovery N 503

30 Bottom Boring 30

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.176 W 9431.492 Water Observations Dry and open 20 upon completion and

to P Pocket Penetrometer tsf after minutes

30 T Torvane tsf

L Lab Vane Shear tsf LOG OF BORING B6 DATE 11 509 ETTL PROJECT Flint Creek Power Plant SURFACE ELEVATION ENGINEERS 1141.3 Gentry Arkansas CONSULTANTS ATTERBERG PROJECT NO G3243 09 BORING TYPE Rotary Wash LIMITS

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

PI 0 20 60 GC

CLAYEY GRAVEL GCmedium dense red N 16 17 29 24 5 28 40Sieve 66 and brown 4 Sieve 48

red and tan N

5 CL LEAN CLAY CL very stiff tan and yellow N 88 40Sieve 24 17 41 18 23 2 4 Sieve 4

hard red N 502

10 ROCK 12 thick layer

LIMESTONE white with layers clayey

of gravel and rock

RQD 0.25 502 40Sieve N 55 59

34 4 Sieve 29

RQD 0.25 N 501

Bottom Boring 23

of Refusal 23 Core broken

bit

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3615.055 W 9431.458 Water Observations Dry and open upon completion P Pocket Penetrometer tsf

T Torvane tsf

L Lab Vane Shear tsf LOG OF BORING B7 DATE 11 609 ETTL PROJECT Flint Creek Power Plant SURFACE ELEVATION ENGINEERS 1140.9 Gentry Arkansas CONSULTANTS ATTERBERG PROJECT NO G3243 09 BORING TYPE Flight Auger LIMITS

BLOW COUNT MAIN OFFICE Natural Moisture Content

80 20 40 60 and

INDEX 1717 East Erwin pcf Qu tsf

UNIT tsf psi Atterberg Limits LIMIT

SIEVE

1 2 3 4 CONTENT Tyler Texas 75702 LIMIT ft USC

STRAIN LEVEL Plastic Moisture Liquid PPR tsf 200

TESTS 903 595 4421 Limit Content Limit 1.0 2.0 3.0 4.0 Ref

DENSITY

LIQUID PLASTIC PLASTICITY Torvane tsf

DEPTH SAMPLES WATER FIELD STRENGTH DATA

GEOLOGIC MATERIAL DESCRIPTION Page

FAILURE OTHER DRY COMPRESSIVE CONFINING MOISTURE MINUS PERFORMED 1.0 2.0 3.0 4.0 STRENGTH PRESSURE 40 80 LL PL

PI 0 20 60 SC

CLAYEY SAND SC medium dense tan and N 23 brown with gravel

GC CLAYEY GRAVEL GCloose tan and brown N 6 5 40Sieve 63

14 23 18

33 4 Sieve 59

5 CL SANDY LEAN CLAY CL stiff red and tan P2.0

with gravel

CL LEAN CLAY WITH SAND CL gray and tan 1.5 9 40 Sieve P 13 24 15 80 4 4 Sieve 0 10 N 502 limestone rock 11

Bottom Boring 11

of Refusal 11

Key Abbrevations Notes Water Level Est Measured Perched to

N SPT Data Blows Ft GPS Coordinates N 3614.995 W 9431.527 Water Observations Seepage 11 while drilling Water level P Pocket Penetrometer tsf 11 and open upon completion T Torvane tsf

L Lab Vane Shear tsf Flint Creek Primary Ash Pond

Low Flow Ralea

= Total Flnwrate 0 0005ft3ldIlfty

h9nleies

FII

Native Soil

Native Rock Flint Creak Primary Ash Pond

High Flow Rates

= Total Flowrate 0 OO46ft3+0ft

Malei als

U FII

Native Soil

H Native Rock Flint Creek Secondary Ash Pond

Low Flow Rates

= TotaI Flowrate 0 0001lft31dlIlfty

I J

Maleials

FII

Native Sails

katia Rock Flint Creek Secondary Ash Pond

High Flow Rates

= Total Flowrate 0 007Sft3rdIlfty

Malaiels

Fil

YYYY Native Soils i x Native Rock Flint Creek Power Station Gentry Arkansas

Primary Ash Pond Steady State with Seismic

SGeotechETTL Engineers 2009 Geote chCnoicnasl uJoltbanFtisleIsn AEP Flint Creek Power Plant Bottom Ash Ponds Geo Stability Analysis Slope Stability Primary seismic

3c2 43 09 SS in

1250 1250 No Soil Soil Moist c Pconst Piez Surf

FS Wt Sat Wt Phi ru

1 Desc pcf pcf psf deg ratio psf

1.3 No No 2 1 129.0 134.0 390.0 20.4 0.00 1

1.3 Fill 0.0 3 2 Native Soil 130.0 133.0 75.0 28.1 0.00 1

1.3 0.0 4 3 Native Rock 148.0 148.0 865.0 35.0 0.00 1

1.3 0.0 5

1.3 1200 6 1200

1.3

1.3 8

1.3 9 8 1 6 4 2 3 7 5 9

1.3

10 1.3

B3 S1 1 1 1150 1 1 1150

B2 B4 S1

B5 B6 B10 B1 B9 S2 S2 B7 B8 S2

S2 S2 S2 S2 1100 B11 1100 S3

1050 1050

1000 1000 0 50 100 150 200 250 300 350 400 GEOSTASE FSmin 1.3

Modified Bishop Method

PLATE P1S Flint Creek Power Station Gentry Arkansas

Primary Ash Pond Rapid Drawdown

ETTLSGeotechEngineers2009 G eCootencshunlitcaanltJsoIbncF iles3243 AEP Flint Creek Power Plant Bottom Ash Ponds Geo Stability Analysis Slope StabilityPrimary RD

09 in

1300 1300 No Soil Soil Moist c Pconst Piez Surf

FS Wt Sat Wt Phi ru

1 Desc pcf pcf psf deg ratio psf

1.2 No No 2 1 130.0 137.0 485.0 12.0 0.00 1

1.2 Fill 0.0 3 2 Native Soil 130.0 133.0 235.0 15.6 0.00 1

1.2 0.0 4 3 Native Rock 148.0 148.0 865.0 34.8 0.00 1

1.2 0.0 5

1.2 1250 6 1250

1.2

1.2 8

1.2 9

1.2

10 1.2

1200 1200

5 6 4 3 7 1 2 9 8

B4 1

B3 S1 B5 1150 1 11150 S1 S1

B2 B6 1 1 S1 S1 B1 B8 B12 B7 B9 B11

S2 S2 S2 B10 S2 S2 S2 B13 1100 S3 1100

1050 1050 0 50 100 150 200 250 300 350 400 GEOSTASE FSmin 1.2

Modified Bishop Method

PLATE P2 Flint Creek Power Station Gentry Arkansas

Secondary Ash Pond Steady State

SETTLGeotechEngineers2009 GeoteCcohnnsicualltaJnotbsFInilecs 3243 AEP Flint Creek Power Plant Bottom Ash Ponds Geo Stability Analysis Slope Stability Secondary SS

09 in

1300 1300 No Soil Soil Moist c Pconst Piez Surf

FS Wt Sat Wt Phi ru

1 Desc pcf pcf psf deg ratio psf

1.6 No No 2 1 130.0 137.0 28.7 0.00 1

1.6 Fill 0.0 0.0 3 2 Native Soil 130.0 133.0 75.0 28.1 0.00 1

1.6 0.0 4 3 Native Rock 148.0 148.0 865.0 34.8 0.00 1

1.6 0.0 5

1.7 1250 6 1250

1.7

1.7 8

1.7 9

1.7

10 1.7

1200 1200

5 6 4 1 2 8 7 3 9

B3 1150 S1 1 1 1150 1 1 B4 B2

S1 B10

B7 B9 S2 B1 S2 B8 S2B11 S2 S2

1100 1100

1050 1050 0 50 100 150 200 250 300 350 400 GEOSTASE FSmin 1.6

Modified Bishop Method

PLATE S1 Flint Creek Power Station Gentry Arkansas

Secondary Ash Pond Steady State with Seismic

SETTLGeotechEngineers2009 GeotecChonnicsaul lJtaobntFsilIensc 3.243 AEP Flint Creek Power Plant Bottom Ash Ponds Geo Stability Analysis Slope Stability Secondary Seismic

09 SS in

1300 1300 No Soil Soil Moist c Pconst Piez Surf

FS Wt Sat Wt Phi ru

1 Desc pcf pcf psf deg ratio psf

1.2 No No 2 1 130.0 137.0 200.0 20.0 0.00 1

1.2 Fill 0.0 3 2 Native Soil 130.0 133.0 75.0 28.1 0.00 1

1.2 0.0 4 3 Native Rock 148.0 148.0 865.0 34.8 0.00 1

1.2 0.0 5

1.2 1250 6 1250

1.2

1.2 8

1.2 9

1.2

10 1.2

1200 1200

7 3 1 4 6 9 2 8 5

B3 1150 S1 1 1 1150 1 1 B4 B2

S1 B10

B7 B9 S2 B1 S2 B8 S2B11 S2 S2

1100 1100

1050 1050 0 50 100 150 200 250 300 350 400 GEOSTASE FSmin 1.2

Modified Bishop Method

PLATE S1S Flint Creek Power Station Gentry Arkansas

Secondary Ash Pond Rapid Drawdown

SETTLGeotechEngineers2009 GeoteCcohnniscualltaJonbtsFIinlecs 3243 AEP Flint Creek Power Plant Bottom Ash Ponds Geo Stability Analysis Slope Stability Secondary RD

09 in

1300 1300 No Soil Soil Moist c Pconst Piez Surf

FS Wt Sat Wt Phi ru

1 Desc pcf pcf psf deg ratio psf

1.5 No No 2 1 130.0 137.0 295.0 13.5 0.00 1

1.5 Fill 0.0 3 2 Native Soil 130.0 133.0 235.0 15.6 0.00 1

1.5 0.0 4 3 Native Rock 148.0 148.0 865.0 34.8 0.00 1

1.5 0.0 5

1.5 1250 6 1250

1.5

1.5 8

1.5 9

1.5

10 1.5

1200 1200

2 1 5 6 3 4 7 8 9

B4 B3 1 S1 B5 1150 1 1 1150 S1 S1 1

B1 B2 S2 S1 B8 B6 B12 S2 B9 B11 S1 B10 S2 B7 B13

S2 S2 S2

1100 1100

1050 1050 0 50 100 150 200 250 300 350 400 GEOSTASE FSmin 1.5

Modified Bishop Method

PLATE S2 PROJECT INFORMATION TRIAXIAL TEST PROGRAM BY GARRY H GREGORY PE

LOCATION Centry AR VERSION AUGUST 1998 REVISED MARCH 24 1999

1.0

PROJECT NO G 3243

09 THIS COPY LICENSED TO CLIENT AEP ETTL ENGINEERS AND CONSULTANTS INC December 2009 1717 East Erwin Tyler 75702

TEST DESCRIPTION

TYPE OF TEST NO CU with PP

SAMPLE TYPE Shelby Tube Sample

DESCRIPTION Redd Brown Tan Gray Fat Clay w Gravel

Sampled Site B2 3 7 deep

on to

ASSUMED SPECIFIC GRAVITY 2.7 Sieve

LL PL Percent 200

REMARKS Diameter and Both Ends Trimmed 4 Sieve

Number Specimens 3 PLATE B1 of

PLATE B2

PLATE B3 TRIAXIAL SHEAR TEST REPORT

PSI

STRESS

SHEAR

70 50 60 30 40 10 20

PRINCIPAL STRESS PSI

f EFFECTIVE STRESS PARAMETERS 33.7 deg c 1.2 psi SPECIMEN NO 1 2 3 4

100.00 INITIAL

Moisture Content 16.9 15.1 21.1

DryDensity pcf 108.9 113.4 107.0 80.00 Diameter inches 2.79 2.75 2.76

PSI Height inches 5.68 4.33 5.19

60.00 AT TEST

Final Moisture 21.7 19.9 19.4

STRESS

DryDensity pcf 109.4 114.8 109.2 40.00 Calculated Diameter in 2.79 2.74 2.73

Height inches 5.68 4.28 5.12

DEVIATOR

20.00 Effect Cell Pressure psi 10.0 20.0 40.0

Failure Stress 12.74 23.73 35.99

psi

Total Pore Pressure psi 62.9 59.0 73.6 0.00 Strain Rate inches min 0.00050 0.00050 0.00050 0.0 10.0 20.0 Failure Strain 1.5 1.6 1.4 AXIAL STRAIN s1 Failure 19.80 34.74 52.37

psi

s3 Failure psi 7.06 11.01 16.38 TEST DESCRIPTION PROJECT INFORMATION

TYPE OFTEST NO CU with PP PROJECT Flint Creek Power Plant

SAMPLE TYPE Shelby Tube Sample LOCATION Centry AR

DESCRIPTION Redd Brown Tan Gray Fat Clay w Gravel PROJECT NO G 3243

Sampled Site B2 3 7 deep CLIENT AEP

on to

ASSUMED SPECIFIC GRAVITY 2.7 Sieve December 2009

LL PL Percent 200 PI ETTL ENGINEERS CONSULTANTS PLATE B1 REMARKS Diameter and Both Ends Trimmed 4 Sieve G 3243 09 B2 37 Flint Creek SPECIMEN NO 1 SPECIMEN NO 2

60 60

40 40

20 20

0 0

10 20

Deviator Stress Excess Pore Pressure Deviator Stress Excess Pore Pressure

psi psi

SPECIMEN NO 3 SPECIMEN NO 4

60 50

0 10

0 0

10 20

20 30 20 10

Deviator Stress Excess Pore Pressure Deviator Stress psi Excess Pore Pressure psi

psi psi

p q DIAGRAM

psi q 20

10 20 30 40 50 60 p

psi

EFFECTIVE STRESS PARAMETERS 1.00 a deg 29.0 a psi

1.0

PROJECT Flint Creek Power Plant TYPE OF TEST NO CU with PP

PROJECT NO G 3243 09 ETTL ENGINEERS CONSULTANTS PLATE B2 DESCRIPTION Redd Brown Tan Gray Fat Clay w Gravel

G 3243 09 B2 37 Flint Creek TRIAXIAL SHEAR TEST REPORT

PSI

STRESS

SHEAR

0 10 20 30 40 50 60 70 80

PRINCIPAL STRESS PSI

TOTAL STRESS PARAMETERS f 15.9 deg c

2.4 psi SPECIMEN NO 1 2 3 4

100.00 INITIAL

Moisture Content 16.9 15.1 21.1

DryDensity pcf 108.9 113.4 107.0 80.00 Diameter inches 2.79 2.75 2.76

PSI Height inches 5.68 4.33 5.19

60.00 AT TEST

Final Moisture 21.7 19.9 19.4

STRESS DryDensity pcf 109.4 114.8 109.2 40.00 Calculated Diameter in 2.79 2.74 2.73

Height inches 5.68 4.28 5.12

20.00 Effect Cell Pressure psi 10.0 20.0 40.0

DEVIATOR

Failure Stress psi 12.74 23.73 35.99

Total Pore Pressure 62.9 59.0 73.6

psi 0.00 Strain Rate inches min 0.00050 0.00050 0.00050 0.0 10.0 20.0 Failure Strain 1.5 1.4

1.6 AXIAL STRAIN s1 Failure 22.74 43.73 75.99

psi

Failure psi s3 10.00 20.00 40.00 TEST DESCRIPTION PROJECT INFORMATION

TYPE OFTEST NO CU with PP PROJECT Flint Creek Power Plant

SAMPLE TYPE Shelby Tube Sample LOCATION Centry AR

DESCRIPTION Redd Brown Tan Gray Fat Clay w Gravel PROJECT NO G 3243

Sampled Site B2 3 7 deep CLIENT AEP

on to

ASSUMED SPECIFIC GRAVITY 2.7 Sieve December 2009

LL PL Percent 200 PI ETTL ENGINEERS CONSULTANTS PLATE B3 REMARKS Diameter and Both Ends Trimmed 4 Sieve PROJECT INFORMATION TRIAXIAL TEST PROGRAM BY GARRY H GREGORY PE

LOCATION Centry AR VERSION AUGUST 1998 REVISED MARCH 24 1999

1.0

PROJECT NO G 3243

09 THIS COPY LICENSED TO CLIENT AEP ETTL ENGINEERS AND CONSULTANTS INC December 2009 1717 East Erwin Tyler 75702

TEST DESCRIPTION

TYPE OF TEST NO CU with PP

SAMPLE TYPE Shelby Tube Sample

DESCRIPTION Reddish Brown Tan Lean Clay

Sampled Site B2 23 35 deep

on to

ASSUMED SPECIFIC GRAVITY 2.7 Sieve

LL PL Percent 200

REMARKS Diameter and Both Ends Trimmed 4 Sieve

Number Specimens 3 PLATE B1 of

PLATE B2

PLATE B3 TRIAXIAL SHEAR TEST REPORT

PSI

STRESS

SHEAR

10 20 30 40 50 60 70 80

PRINCIPAL STRESS PSI

f EFFECTIVE STRESS PARAMETERS 33.0 deg c 0.6 psi SPECIMEN NO 1 2 3 4

100.00 INITIAL

Moisture Content 21.8 20.0 17.7

DryDensity pcf 103.5 109.2 114.4 80.00 Diameter inches 2.78 2.76 2.80

PSI Height inches 5.68 5.67 5.69

60.00 AT TEST

Final Moisture 23.5 21.0 16.6

STRESS

DryDensity pcf 103.8 110.3 117.0 40.00 Calculated Diameter in 2.77 2.74 2.78

Height inches 5.65 5.63 5.64

DEVIATOR

20.00 Effect Cell Pressure psi 10.0 20.0 40.0

Failure Stress 16.18 20.70 42.40

psi

Total Pore Pressure psi 55.6 60.4 73.9 0.00 Strain Rate inches min 0.00050 0.00050 0.00050 0.0 10.0 20.0 Failure Strain 1.5 1.5 1.5 AXIAL STRAIN s1 Failure 20.55 30.34 58.49

psi

s3 Failure psi 4.37 9.64 16.09 TEST DESCRIPTION PROJECT INFORMATION

TYPE OFTEST NO CU with PP PROJECT Flint Creek Power Plant

SAMPLE TYPE Shelby Tube Sample LOCATION Centry AR

DESCRIPTION Reddish Brown Tan Lean Clay PROJECT NO G 3243

Sampled Site B2 deep CLIENT AEP

on 23 to 35

ASSUMED SPECIFIC GRAVITY 2.7 Sieve December 2009

LL PL Percent 200 PI ETTL ENGINEERS CONSULTANTS PLATE B1 REMARKS Diameter and Both Ends Trimmed 4 Sieve G 3243 09 B2 23 35 Flint Creek SPECIMEN NO 1 SPECIMEN NO 2

60 60

40 40

20 20

0 0

10 20

Deviator Stress Excess Pore Pressure Deviator Stress Excess Pore Pressure

psi psi

SPECIMEN NO 3 SPECIMEN NO 4

100

0 0 0

10 20 0

20 30 20 10

Deviator Stress Excess Pore Pressure Deviator Stress psi Excess Pore Pressure psi

psi psi

p q DIAGRAM

psi q 20

10 20 30 40 50 60 p

psi

EFFECTIVE STRESS PARAMETERS 0.98 a deg 28.6 a psi

0.5

PROJECT Flint Creek Power Plant TYPE OF TEST NO CU with PP

PROJECT NO G 3243 09 ETTL ENGINEERS CONSULTANTS PLATE B2 DESCRIPTION Reddish Brown Tan Lean Clay

G 3243 09 B2 23 35 Flint Creek TRIAXIAL SHEAR TEST REPORT

PSI

STRESS

SHEAR

0 0 10 20 30 40 50 60 70 80 90

100 PRINCIPAL STRESS PSI

TOTAL STRESS PARAMETERS f 18.3 deg c 1.9 psi

SPECIMEN NO 1 2 3 4

100.00 INITIAL

Moisture Content 21.8 20.0 17.7

Dry Density pcf 103.5 109.2 114.4 80.00 Diameter inches 2.78 2.76 2.80

PSI Height inches 5.68 5.67 5.69

60.00 AT TEST

Final Moisture 23.5 21.0 16.6

STRESS Dry Density pcf 103.8 110.3 117.0 40.00 Calculated Diameter in 2.77 2.74 2.78

Height inches 5.65 5.63 5.64

20.00 Effect Cell Pressure 10.0 20.0 40.0

psi

DEVIATOR Failure Stress psi 16.18 20.70 42.40

Total Pore Pressure psi 55.6 60.4 73.9 0.00 Strain Rate inches min 0.00050 0.00050 0.00050 0.0 10.0 20.0 Failure Strain 1.5 1.5 1.5 AXIAL STRAIN s 1 Failure psi 26.18 40.70 82.40

s3 Failure 10.00 20.00 40.00

psi TEST DESCRIPTION PROJECT INFORMATION

TYPE OFTEST NO CU with PROJECT Flint Creek Power Plant

PP SAMPLE TYPE Shelby Tube Sample LOCATION Centry AR

DESCRIPTION Reddish Brown Tan Lean Clay PROJECT NO G 3243

09 Sampled Site B2 23 deep CLIENT AEP

on to 35

ASSUMED SPECIFIC GRAVITY 2.7 Sieve December 2009

40 LL PL PI Percent 200 ETTL ENGINEERS CONSULTANTS PLATE B3 REMARKS Diameter and Both Ends Trimmed 4 Sieve PROJECT INFORMATION TRIAXIAL TEST PROGRAM BY GARRY H GREGORY PE

LOCATION Centry AR VERSION 1.0 AUGUST 1998 REVISED MARCH 24 1999

PROJECT NO G 3243

09 THIS COPY LICENSED TO CLIENT AEP ETTL ENGINEERS AND CONSULTANTS INC December 2009 1717 East Erwin Tyler TX 75702

TEST DESCRIPTION

TYPE OF TEST NO CU with

SAMPLE TYPE Shelby Tube Sample

DESCRIPTION Redd Brown Tan Sandy Lean Clay w Gravel

Sampled Site B3 3 7 deep

on to

ASSUMED SPECIFIC GRAVITY 2.7 Sieve

LL PL Percent 200

REMARKS Diameter and Both Ends Trimmed 4 Sieve

Number Specimens 3 PLATE B1 of

PLATE B2

PLATE B3 TRIAXIAL SHEAR TEST REPORT

PSI

STRESS

SHEAR

60 50 20 40 10 30

PRINCIPAL STRESS PSI

f EFFECTIVE STRESS PARAMETERS 24.0 deg c 3.2 psi SPECIMEN NO 1 2 3 4

60.00 INITIAL

Moisture Content 17.6 20.3 17.6

DryDensity pcf 107.9 106.2 107.7

Diameter inches 2.76 2.76 2.77

PSI

40.00 Height inches 5.68 5.68 5.68 AT TEST

Final Moisture 24.0 22.3 22.0

STRESS

DryDensity pcf 108.5 107.0 109.8

Calculated Diameter in 2.76 2.75 2.75 20.00 Height inches 5.67 5.64 5.62

DEVIATOR

Effect Cell Pressure psi 10.0 20.0 40.0

Failure Stress 19.56 19.31 36.95

psi

Total Pore Pressure psi 54.4 61.2 70.5 0.00 Strain Rate inches min 0.00050 0.00050 0.00050 10.0 20.0

0.0 Failure Strain 1.5 1.5 2.1 AXIAL STRAIN s1 Failure 25.12 28.08 56.49

psi

s3 Failure psi 5.56 8.77 19.54 TEST DESCRIPTION PROJECT INFORMATION

TYPE OFTEST NO CU with PP PROJECT Flint Creek Power Plant

SAMPLE TYPE Shelby Tube Sample LOCATION Centry AR

DESCRIPTION Redd Brown Tan Sandy Lean Clay w Gravel PROJECT NO G 3243

Sampled Site B3 3 7 deep CLIENT AEP

on to

ASSUMED SPECIFIC GRAVITY 2.7 Sieve December 2009

LL PL Percent 200 PI ETTL ENGINEERS CONSULTANTS PLATE B1 REMARKS Diameter and Both Ends Trimmed 4 Sieve G 3243 09 B3 57 Flint Creek SPECIMEN NO 1 SPECIMEN NO 2

60 60

40 40

20 20

0 0

10 20

Deviator Stress Excess Pore Pressure Deviator Stress Excess Pore Pressure

psi psi

SPECIMEN NO 3 SPECIMEN NO 4

60 50

0 10

0 0

10 20

20 30 20 10

Deviator Stress Excess Pore Pressure Deviator Stress psi Excess Pore Pressure psi

psi psi

p q DIAGRAM

psi q 20

10 20 30 40 50 60 p

psi

EFFECTIVE STRESS PARAMETERS 0.98 a deg 22.2 a psi

2.9

PROJECT Flint Creek Power Plant TYPE OF TEST NO CU with PP

PROJECT NO G 3243 09 ETTL ENGINEERS CONSULTANTS PLATE B2 DESCRIPTION Redd Brown Tan Sandy Lean Clay w Gravel

G 3243 09 B3 57 Flint Creek TRIAXIAL SHEAR TEST REPORT

PSI

STRESS

SHEAR

0 10 20 30 40 50 60 70 80

PRINCIPAL STRESS PSI

TOTAL STRESS PARAMETERS f 14.1 deg c

4.0 psi SPECIMEN NO 1 2 3 4

60.00 INITIAL

Moisture Content 17.6 20.3 17.6

DryDensity pcf 107.9 106.2 107.7

Diameter inches 2.76 2.76 2.77

PSI 40.00 Height inches 5.68 5.68 5.68 AT TEST

Final Moisture 24.0 22.3 22.0

STRESS DryDensity pcf 108.5 107.0 109.8

Calculated Diameter in 2.76 2.75 2.75 20.00 Height inches 5.67 5.64 5.62

Effect Cell Pressure psi 10.0 20.0 40.0

DEVIATOR

Failure Stress psi 19.56 19.31 36.95

Total Pore Pressure 54.4 61.2 70.5

psi 0.00 Strain Rate inches min 0.00050 0.00050 0.00050 0.0 10.0 20.0 Failure Strain 1.5 2.1

1.5 AXIAL STRAIN s1 Failure 29.56 39.31 76.95

psi

Failure psi s3 10.00 20.00 40.00 TEST DESCRIPTION PROJECT INFORMATION

TYPE OFTEST NO CU with PP PROJECT Flint Creek Power Plant

SAMPLE TYPE Shelby Tube Sample LOCATION Centry AR

DESCRIPTION Redd Brown Tan Sandy Lean Clay w Gravel PROJECT NO G 3243

Sampled Site B3 3 7 deep CLIENT AEP

on to

ASSUMED SPECIFIC GRAVITY 2.7 Sieve December 2009

LL PL Percent 200 PI ETTL ENGINEERS CONSULTANTS PLATE B3 REMARKS Diameter and Both Ends Trimmed 4 Sieve Analysis Rock Strength using RocLab

Hoek Brown Classification intact uniaxial comp strength sigci 4.5

ksi GSI 8 Disturbance factor 0

10 mi D 0.16 intact modulus 1600

Ei ksi

Hoek Brown Criterion mb 0.321 s 4.54e 5 a 0.585 0.15 Mohr Coulomb

Fit cohesion 0.007 friction angle 38.55 deg

ksi 0.14 Rock Mass Parameters tensile strength 0.001

ksi uniaxialcompressive strength 0.013 0.13 ksi global strength 0.209

ksi deformation modulus 48.81

ksi

0.12

0.11

0.10

ksi

0.09

stress

0.08

principal

0.07

Major

0.06

0.05 0.05

0.04 0.04

ksi

0.03 0.03

stress

0.02 0.02

Shear

0.01 0.01

0.00 0.01 0.02 0.03 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07

Minor principal stress ksi Normal stress ksi ETTL Engineers Consultants Inc

GEOTECHNICAL _ MATERIALS _ ENVIRONMENTAL _ DRILLING _ LANDFILLS

HYDRAULIC CONDUCTIVITY DETERMINATION FLEXIBLE WALL PERMEAMETER CONSTANT VOLUME Mercury Permometer Test

Project AEP Flint Creek Power Plant Bottom Ash Ponds Date 12292009 Panel Number P3 ASTM D 5084

Project No G 3243 095 Permometer Data

Set Mercury

cm2 to cm3 Boring No B1 0.031416 Equilibrium ap Pipet Rp 1.7

at Sample 0.767120 cm2 beginning Pipet cm3

6.7 Annulus cm3

Depth 1820 0.030180 C 0.000433212 Ra

ft M1 1.5

Other Location 1.040953 T 0.201660671

Material Description Gray Tan Red Clayey Gravel

SAMPLE DATA

Wet Wt sample ring tare 538.52 g

or Tare ring Wt 0.0 g Before Test After Test

or Wet Wt Sample 538.52 g Tare No T 5 Tare No T

of 25

Diameter 2.76 7.01 cm2 Wet Wt tare 538.52 Wet Wt tare 662.56

in Length 2.74 6.97 cm Dry Wt tare 433.64 Dry Wt tare 549.81

in Area 5.97 2 38.54 cm2 Tare Wt 0.00 Tare Wt 116.17

in Volume 16.40 3 268.68 cm3 Dry Wt 433.64 Dry Wt 433.64

in 3 Unit Wt wet 125.07 2.00 gcm Water Wt 104.88 Water Wt 112.75

pcf 3 Unit Wt dry 100.71 1.61 gcm moist 24.2 moist 26.0

pcf

Assumed Specific Gravity 2.75 Max Dry Density pcf 100.7528 OMC 24.1859607 max 100.0 OMC 0.00

Calculated saturation 101.46 Void ratio e 0.70 Porosity n 0.41

TEST READINGS

Z1 Mercury Height Difference 5.2 cm Hydraulic Gradient 9.33

Date elapsed t Z DZp temp a k k

seconds pipet t cm deg C temp corr cmsec day Reset

ft 12292009 3300 6 0.6588251 24.5 0.899 1.68E 4.77E

08 05 12292009 4080 5.9 0.7588251 24.5 0.899 1.59E 4.50E

08 05 12292009 4980 5.8 0.8588251 24.5 0.899 1.49E 4.22E

08 05 12292009 6120 5.7 0.9588251 24.5 0.899 1.37E 3.88E

08 05

SUMMARY

1.53E cmsec Acceptance criteria

ka 08 25 Vm

ki 1.68E cmsec 9.9 Vm x 100

k1 08 ka ki 1.59E cmsec 3.6

k2 08 ka 1.49E cmsec 2.8

k3 08 1.37E cmsec 10.7

k4 08

Hydraulic conductivity k 1.53E cm sec 4.34E day

08 05 ft Void Ratio e 0.70

Porosity n 0.41

Bulk Density g 2.00 gcm3 125.1 pcf Water Content W 0.39 cm3 cm3 deg C

at 20 cm2 Intrinsic Permeability 1.57E deg C

kint 13 at 20

210 Beech Street 1717 East Erwin 707 West Cotton Street Texarkana AR 71854 Tyler Texas 75702 Longview Texas 756045505 870 7720013 Phone 903 595 4421 Phone 903 758 0915 Phone 870 2162413 Fax 903 5956113 Fax 903 758 8245 Fax www ettlinc com ETTL Engineers Consultants Inc

GEOTECHNICAL _ MATERIALS _ ENVIRONMENTAL _ DRILLING _ LANDFILLS

HYDRAULIC CONDUCTIVITY DETERMINATION FLEXIBLE WALL PERMEAMETER CONSTANT VOLUME Mercury Permometer Test

Project AEP Flint Creek Power Plant Bottom Ash Ponds Date 12292009 Panel Number P3 ASTM D 5084

Project No G 3243 095 Permometer Data

Set Mercury

cm2 to cm3 Boring No B1 0.031416 Equilibrium 1.8 ap Pipet Rp

at Sample 0.767120 cm2 beginning Pipet cm3

6.7 Depth 33 0.030180 C 0.000429887 Annulus Ra 1.5 cm3

ft 35 M1

Other Location 1.040953 T 0.203783414

Material Description Red Tan Lean Clay

SAMPLE DATA

Wet Wt sample ring tare 584.74 g

or Tare ring Wt 0.0 g Before Test After Test

or Wet Wt Sample 584.74 g Tare No T 7 Tare No T

of 24

Diameter 2.79 7.09 cm2 Wet Wt tare 422.13 Wet Wt tare 698.21

in Length 2.79 7.08 cm Dry Wt tare 390.91 Dry Wt tare 599.86

in Area 6.12 2 39.47 cm2 Tare Wt 221.16 Tare Wt 112.38

Volume 17.06 3 279.61 cm3 Dry Wt 169.75 Dry Wt 487.48

in 3 Unit Wt wet 130.49 2.09 gcm Water Wt 31.22 Water Wt 98.35

pcf 3 Unit Wt dry 110.22 pcf 1.77 gcm moist 18.4 moist 20.2

Assumed Specific Gravity 2.72 Max Dry Density pcf 110.2688 OMC 18.3917526 max 100.0 OMC 0.00

Calculated saturation 101.51 Void ratio e 0.54 Porosity n 0.35

TEST READINGS

Z1Mercury Height Difference 5.1 cm Hydraulic Gradient 9.09

Date elapsed t Z DZp temp a k k

seconds pipet t cm deg C temp corr cmsec day Reset

ft 12292009 3480 6 0.657171 24.5 0.899 1.60E 4.53E

08 05 12292009 4260 5.9 0.757171 24.5 0.899 1.52E 4.31E

08 05 12292009 4920 5.8 0.857171 24.5 0.899 1.51E 4.28E

08 05 12292009 6420 5.6 1.057171 24.5 0.899 1.46E 4.14E

08 05

SUMMARY

1.52E cm sec Acceptance criteria

ka 08 25 Vm

ki 1.60E cm sec 4.9 Vm ka x 100

k1 08 ki 1.52E cm sec 0.1

k2 08 ka 1.51E cm sec 0.9

k3 08 1.46E cm sec 4.0

k4 08

Hydraulic conductivity k 1.52E cmsec 4.31E day

08 05 ft Void Ratio e 0.54

Porosity n 0.35

Bulk Density g 2.09 gcm3 130.5 pcf Water Content W 0.33 cm3 cm3 deg C

at 20 cm2 Intrinsic Permeability 1.56E deg C

kint 13 at 20

210 Beech Street 1717 East Erwin 707 West Cotton Street Texarkana AR 71854 Tyler Texas 75702 Longview Texas 756045505 870 772 0013 Phone 903 595 4421 Phone 903758 0915 Phone 870 216 2413 Fax 903 5956113 Fax 903 7588245 Fax www ettlinc com ETTL Engineers Consultants Inc

GEOTECHNICAL _ MATERIALS _ ENVIRONMENTAL _ DRILLING _ LANDFILLS

HYDRAULIC CONDUCTIVITY DETERMINATION FLEXIBLE WALL PERMEAMETER CONSTANT VOLUME Mercury Permometer Test

Project AEP Flint Creek Power Plant Bottom Ash Ponds Date 12292009 Panel Number P3 ASTM D 5084

Project No G 3243 095 Permometer Data

Set Mercury

cm2 to cm3 Boring No B2 0.031416 Equilibrium ap Pipet Rp 1.7

at Sample 0.767120 cm2 beginning Pipet cm3

6.7 Annulus cm3 Depth 810 0.030180 C 0.000430497 Ra

ft M1 1.5

Other Location 1.040953 T 0.201660671

Material Description Red Tan Clayey Gravel

SAMPLE DATA

Wet Wt sample ring tare 570.81 g

or Tare ring Wt 0.0 g Before Test After Test

or Wet Wt Sample 570.81 g Tare No T 2 Tare No T

of 23

Diameter 2.78 7.06 cm2 Wet Wt tare 299.84 Wet Wt tare 715.92

in Length 2.77 7.03 cm Dry Wt tare 287.43 Dry Wt tare 608.75

in Area 6.06 2 39.10 cm2 Tare Wt 216.62 Tare Wt 140.31

in Volume 16.77 3 274.83 cm3 Dry Wt 70.81 Dry Wt 468.44

in 3 Unit Wt wet 129.60 2.08 gcm Water Wt 12.41 Water Wt 107.17

pcf 3 Unit Wt dry 110.28 1.77 gcm moist 17.5 moist 22.9

pcf

Assumed Specific Gravity 2.95 Max Dry Density pcf 110.3225 OMC 17.5257732 max 100.0 OMC 0.00

Calculated saturation 100.72 Void ratio e 0.67 Porosity n 0.40

TEST READINGS

Z1 Mercury Height Difference 5.2 cm Hydraulic Gradient 9.25

Date elapsed t Z DZp temp a k k

seconds pipet t cm deg C temp corr cmsec day Reset

ft 12292009 2460 6.3 0.3588251 24.5 0.899 1.18E 3.35E

08 05 12292009 3900 6.2 0.4588251 24.5 0.899 9.64E 2.73E

09 05 12292009 5520 6.1 0.5588251 24.5 0.899 8.39E 2.38E

09 05

12292009 7200 6 0.6588251 24.5 0.899 7.67E 2.17E

09 05

SUMMARY

9.38E cmsec Acceptance criteria

ka 09 50 Vm

ki 1.18E cmsec 26.1 Vm x 100

k1 08 ka ki 9.64E cmsec 2.8

k2 09 ka 8.39E cmsec 10.6

k3 09 7.67E cmsec 18.3

k4 09

Hydraulic conductivity k 9.38E cm sec 2.66E day

09 05 ft Void Ratio e 0.67

Porosity n 0.40

Bulk Density g 2.08 gcm3 129.6 pcf Water Content W 0.31 cm3 cm3 deg C

at 20 cm2 Intrinsic Permeability 9.61E deg C

kint 14 at 20

210 Beech Street 1717 East Erwin 707 West Cotton Street Texarkana AR 71854 Tyler Texas 75702 Longview Texas 756045505 870 772 0013 Phone 903 595 4421 Phone 903758 0915 Phone 870 216 2413 Fax 903 5956113 Fax 903 7588245 Fax www ettlinc com ETTL Engineers Consultants Inc

GEOTECHNICAL _ MATERIALS _ ENVIRONMENTAL _ DRILLING _ LANDFILLS

HYDRAULIC CONDUCTIVITY DETERMINATION FLEXIBLE WALL PERMEAMETER CONSTANT VOLUME Mercury Permometer Test

Project AEP Flint Creek Power Plant Bottom Ash Ponds Date 12292009 Panel Number P3 ASTM D 5084

Project No G 3243 095 Permometer Data

Set Mercury

cm2 to cm3 Boring No B2 0.031416 Equilibrium ap Pipet Rp 1.7

at Sample 0.767120 cm2 beginning Pipet cm3

6.7 Annulus cm3

Depth 2325 0.030180 C 0.000430195 Ra

ft M1 1.5

Other Location 1.040953 T 0.201660671

Material Description Red Tan Sandy Lean Clay

SAMPLE DATA

Wet Wt sample ring tare 586.16 g

or Tare ring Wt 0.0 g Before Test After Test

or Wet Wt Sample 586.16 g Tare No T 8 Tare No T

of 27

Diameter 2.79 7.08 cm2 Wet Wt tare 586.16 Wet Wt tare 730.20

in Length 2.79 7.07 cm Dry Wt tare 505.60 Dry Wt tare 646.06

in Area 6.10 2 39.39 cm2 Tare Wt 0.00 Tare Wt 140.46

in Volume 17.00 3 278.61 cm3 Dry Wt 505.6 Dry Wt 505.6

in 3 Unit Wt wet 131.28 2.10 gcm Water Wt 80.56 Water Wt 84.14

pcf 3 Unit Wt dry 113.24 1.81 gcm moist 15.9 moist 16.6

pcf

Assumed Specific Gravity 2.60 Max Dry Density pcf 113.2859 OMC 15.9335443 max 100.0 OMC 0.00

Calculated saturation 99.83 Void ratio e 0.43 Porosity n 0.30

TEST READINGS

Z1 Mercury Height Difference 5.2 cm Hydraulic Gradient 9.19

Date elapsed t Z DZp temp a k k

seconds pipet t cm deg C temp corr cmsec day Reset

ft 12292009 2400 6 0.6588251 0.910 2.32E 6.59E

24 08 05 12292009 3540 5.7 0.9588251 0.910 2.38E 6.73E

24 08 05 12292009 3960 5.6 1.0588251 0.910 2.37E 6.73E

24 08 05 12292009 4380 5.5 1.1588251 0.910 2.38E 6.74E

24 08 05

SUMMARY

2.36E cmsec Acceptance criteria

ka 08 25 Vm

ki 2.32E cmsec 1.6 Vm x 100

k1 08 ka ki 2.38E cmsec 0.5

k2 08 ka 2.37E cmsec 0.5

k3 08 2.38E cmsec 0.6

k4 08

Hydraulic conductivity k 2.36E cm sec 6.70E day

08 05 ft Void Ratio e 0.43

Porosity n 0.30

Bulk Density g 2.10 gcm3 131.3 pcf Water Content W 0.29 cm3 cm3 deg C

at 20 cm2 Intrinsic Permeability 2.42E deg C

kint 13 at 20

210 Beech Street 1717 East Erwin 707 West Cotton Street Texarkana AR 71854 Tyler Texas 75702 Longview Texas 756045505 870 772 0013 Phone 903 595 4421 Phone 903758 0915 Phone 870 216 2413 Fax 903 5956113 Fax 903 7588245 Fax www ettlinc com ETTL Engineers Consultants Inc

GEOTECHNICAL _ MATERIALS _ ENVIRONMENTAL _ DRILLING _ LANDFILLS

HYDRAULIC CONDUCTIVITY DETERMINATION FLEXIBLE WALL PERMEAMETER CONSTANT VOLUME Mercury Permometer Test

Project AEP Flint Creek Power Plant Bottom Ash Ponds Date 12292009 Panel Number P3 ASTM D 5084

Project No G 3243 095 Permometer Data

Set Mercury

cm2 to cm3 Boring No B7 0.031416 Equilibrium ap Pipet Rp 1.7

at Sample 0.767120 cm2 beginning Pipet cm3

6.7 Annulus cm3 Depth 57 0.030180 C 0.000434383 Ra

ft M1 1.5

Other Location 1.040953 T 0.201660671

Material Description Red Tan Sandy Lean Clay with gravel

SAMPLE DATA

Wet Wt sample ring tare 540.64 g

or Tare ring Wt 0.0 g Before Test After Test

or Wet Wt Sample 540.64 g Tare No T 4 Tare No T

of 20

Diameter 2.75 6.98 cm2 Wet Wt tare 439.69 Wet Wt tare 707.29

in Length 2.73 6.94 cm Dry Wt tare 400.57 Dry Wt tare 600.06

in Area 5.93 2 38.26 cm2 Tare Wt 219.47 Tare Wt 160.23

in Volume 16.20 3 265.52 cm3 Dry Wt 181.1 Dry Wt 439.83

in 3 Unit Wt wet 127.05 2.04 gcm Water Wt 39.12 Water Wt 107.23

pcf 3 Unit Wt dry 104.48 1.67 gcm moist 21.6 moist 24.4

pcf

Assumed Specific Gravity 2.80 Max Dry Density pcf 104.5286 OMC 21.6013252 max 100.0 OMC 0.00

Calculated saturation 101.43 Void ratio e 0.67 Porosity n 0.40

TEST READINGS

Z1 Mercury Height Difference 5.2 cm Hydraulic Gradient 9.37

Date elapsed t Z DZp temp a k k

seconds pipet t cm deg C temp corr cmsec day Reset

ft 12292009 3120 5.9 0.7588251 24.5 0.899 2.08E 5.90E

08 05 12292009 3720 5.8 0.8588251 24.5 0.899 2.00E 5.66E

08 05 12292009 4380 5.7 0.9588251 24.5 0.899 1.92E 5.43E

08 05 12292009 5040 5.6 1.0588251 24.5 0.899 1.86E 5.28E

08 05

SUMMARY

1.96E cmsec Acceptance criteria

ka 08 25 Vm

ki 2.08E cmsec 5.9 Vm x 100

k1 08 ka ki 2.00E cmsec 1.7

k2 08 ka 1.92E cmsec 2.4

k3 08 1.86E cmsec 5.2

k4 08

Hydraulic conductivity k 1.96E cm sec 5.57E day

08 05 ft Void Ratio e 0.67

Porosity n 0.40

Bulk Density g 2.04 gcm3 127.1 pcf Water Content W 0.36 cm3 cm3 deg C

at 20 cm2 Intrinsic Permeability 2.01E deg C

kint 13 at 20

210 Beech Street 1717 East Erwin 707 West Cotton Street Texarkana AR 71854 Tyler Texas 75702 Longview Texas 756045505 870 772 0013 Phone 903 595 4421 Phone 903758 0915 Phone 870 216 2413 Fax 903 5956113 Fax 903 7588245 Fax www ettlinc com Well No 1 ENVIRONMENTAL LOG B Client Flint Creek Power Plant Location Gentry Arkansas

Project No G3243 09 Phase Task Surface Elev Page 1 2

Overburden Lithologic Data Well Well Construction Construction

Field Log

Feet Feet

Depth Description Graphics Depth Details

Sampler Graphic

Strength TOC Elev

0 Ground Surface 0

CLAYEY GRAVEL GC red and tan

5 5

dense

red tan and white

medium dense

10 10

15 15

native soil

gray tan and red moist

20 20

LEAN CLAY CL red and tan saturated

25 25

Continued Next Page

Driller Tommy Cook Drilling Method Rotary Wash Bentonite Seal 04 2248

Logged By James Griffith Borehole Diameter 6.5 Filter Pack Qty 1022

Drilling Started 11309 Well Casing 2.0 Dia 0.0 12.0 Filter Pack Type 2040 Sand

Drilling Completed 11309 Casing Type PVC Static Water Level

Construction Completed Well Screen 2.0 Dia 12.0 22.0

Development Completed Screen Type Slotted Notes Seepage 25 while drilling

Type Well Slot Size 0.010

Grout Type Bentonite

ETTL Engineers Consultants Inc Well No 1 ENVIRONMENTAL LOG B Client Flint Creek Power Plant Location Gentry Arkansas

Project No G3243 09 Phase Task Surface Elev Page 2 2

Overburden Lithologic Data Well Well Construction Construction

Field Log

Feet Feet

Depth Description Graphics Depth Details

Sampler Graphic

Strength

Continued fromprevious page

SANDY FAT CLAY CH hard red and tan with gravel

30 30

LEAN CLAY CL very stiff red and tan

35 35

LEAN CLAY WITH SAND CL very stiff red and gray

40 40

LIMESTONE moderately strong limestone seams 16 gray

crystalline clay thick bedded fresh unfeatured

45 45

RQD 0.25

Bottom Boring 48

ETTL Engineers Consultants Inc Well No 2 ENVIRONMENTAL LOG B Client Flint Creek Power Plant Location Gentry Arkansas

Project No G3243 09 Phase Task Surface Elev Page 1 2

Overburden Lithologic Data Well Well Construction Construction

Field Log

Feet Feet

Depth Description Graphics Depth Details

Sampler Graphic

Strength TOC Elev

0 Ground Surface 0

CLAYEY GRAVEL GC medium dense red and tan with gravel

FAT CLAY WITH SAND CH stiff red and tan

5 5

CLAYEY GRAVEL GC medium dense red and tan with sand and gravel

10 10

SANDY LEAN CLAY CL red and tan with gravel

15 15

CLAYEY GRAVEL GC medium dense red and tan moist

native soil 20 20

SANDY LEAN CLAY CL very stiff red and tan with gravel

25 25

Continued Next Page

Driller Tommy Cook Drilling Method Rotary Wash Bentonite Seal 03 2550

Logged By James Griffith Borehole Diameter 6.5 Filter Pack Qty 1325

Drilling Started 11309 Well Casing 2.0 Dia 0.0 15.0 Filter Pack Type 2040 Sand

Drilling Completed 11309 Casing Type PVC Static Water Level

Construction Completed Well Screen 2.0 Dia 15.0 25.0

Development Completed Screen Type Slotted Notes Seepage 20 while drilling

Type Well Slot Size 0.010

Grout Type Bentonite

ETTL Engineers Consultants Inc Well No 2 ENVIRONMENTAL LOG B Client Flint Creek Power Plant Location Gentry Arkansas

Project No G3243 09 Phase Task Surface Elev Page 2 2

Overburden Lithologic Data Well Well Construction Construction

Field Log

Feet Feet

Depth Description Graphics Depth Details

Sampler Graphic

Strength

Continued fromprevious page

30 30

35 35

LIMESTONE 14 thick layer

LIMESTONE 8 thick limestone ledge

40 40

45 45

rock cuttings RQD 0.25

solid rock seam 48

50 50 Bottom Boring 50

ETTL Engineers Consultants Inc Well No 3 ENVIRONMENTAL LOG B Client Flint Creek Power Plant Location Gentry Arkansas

Project No G3243 09 Phase Task Surface Elev Page 1 2

Overburden Lithologic Data Well Well Construction Construction

Field Log

Feet Feet

Depth Description Graphics Depth Details

Sampler Graphic

Strength TOC Elev

0 Ground Surface 0

SANDY LEAN CLAY CL very stiff gray and tan with gravel

brown and red with gravel

5 5

gray and tan with gravel

SANDY FAT CLAY CH stiff tan and red with gravel

10 10

very stiff

15 15

CLAYEY GRAVEL GC medium dense gray and tan with gravel

native soil 20 20

brown

25 25

Continued Next Page

Driller Tommy Cook Drilling Method Rotary Wash Bentonite Seal 02 2337

Logged By James Griffith Borehole Diameter 6.5 Filter Pack Qty 1323

Drilling Started 11409 Well Casing 2.0 Dia 0.0 13.0 Filter Pack Type 2040 Sand

Drilling Completed 11409 Casing Type PVC Static Water Level

Construction Completed Well Screen 2.0 Dia 13.0 23.0

Development Completed Screen Type Slotted Notes

Type Well Slot Size 0.010

Grout Type Bentonite

ETTL Engineers Consultants Inc Well No 3 ENVIRONMENTAL LOG B Client Flint Creek Power Plant Location Gentry Arkansas

Project No G3243 09 Phase Task Surface Elev Page 2 2

Overburden Lithologic Data Well Well Construction Construction

Field Log

Feet Feet

Depth Description Graphics Depth Details

Sampler Graphic

Strength

Continued fromprevious page

LIMESTONE rock cuttings

30 30 RQD 0.25

LIMESTONE

35 35

RQD 0.25

Bottom Boring 37

ETTL Engineers Consultants Inc Well No 4 ENVIRONMENTAL LOG B Client Flint Creek Power Plant Location Gentry Arkansas

Project No G3243 09 Phase Task Surface Elev Page 1 2

Overburden Lithologic Data Well Well Construction Construction

Field Log

Feet Feet

Depth Description Graphics Depth Details

Sampler Graphic

Strength TOC Elev

0 Ground Surface 0

SANDY LEAN CLAY CL stiff tan and gray with gravel

5 5 CLAYEY GRAVEL GC medium dense tan and red

LEAN CLAY WITH GRAVEL CL stiff red and tan

10 10

reddish brown and tan

15 15

SANDY LEAN CLAY CL very stiff tan and gray with gravel

native soil 20 20

CLAYEY GRAVEL GC medium dense tan and red with gravel

25 25

Continued Next Page

Driller Tommy Cook Drilling Method Rotary Wash Bentonite Seal 03 2350

Logged By James Griffith Borehole Diameter 6.5 Filter Pack Qty 1323

Drilling Started 11409 Well Casing 2.0 Dia 0.0 13.0 Filter Pack Type 2040 Sand

Drilling Completed 11409 Casing Type PVC Static Water Level

Construction Completed Well Screen 2.0 Dia 13.0 23.0

Development Completed Screen Type Slotted Notes

Type Well Slot Size 0.010

Grout Type Bentonite

ETTL Engineers Consultants Inc Well No 4 ENVIRONMENTAL LOG B Client Flint Creek Power Plant Location Gentry Arkansas

Project No G3243 09 Phase Task Surface Elev Page 2 2

Overburden Lithologic Data Well Well Construction Construction

Field Log

Feet Feet

Depth Description Graphics Depth Details

Sampler Graphic

Strength

Continued fromprevious page

SANDY LEAN CLAY CL very stiff tan red and gray with gravel

30 30

CLAYEY GRAVEL GC loose tan gray and red saturated

35 35

SANDY LEAN CLAY CL very stiff tan gray and red with gravel

40 40

soft

GRAVEL GP white 45 45

SANDY LEAN CLAY CL stiff red with gravel

50 50 Bottom Boring 50

ETTL Engineers Consultants Inc STATE OF ARKANSAS REPORT ON WATER WELL CONSTRUCTION PUMP INSTALLATION

ETTL A Contractor Name Number Engineers Consultants Tnc c111401 10 LOCATE WITH X IN 2 Driller 2418 NameName Number Thomas Cook D SECTION BELOW

3 Pump Installer Name Number P 2009 4 Date Well Completed Nov 3 New Well Replace or Workover _ 5 COUNTY 6 FRACTION 7 SECTION 8 TOWNSHIP 9 RANGE Benton NE of SW A of 8 T1 8N R33W LONGITUDE LATITUDE 94 36 15 11 11 0 03 I

B1 DESCRIPTION OF FORMATION IN DEPTHS FEET ®1 LAND OWNER OR OTHER CONTACT PERSON

B1 FROM I TO NAME AEP

STREET ADDRESS clayey sandRed Tan 0 22 21797 SWEPCO Plant Rd CITY Gentry AR 72734 Gray 2 CASING FROM t 0 TO 1 2 W 2 ID FROM TO W ID TYPE CASING PVC

3 SCREEN TYPE 2 tt PVC DIA SLOTGA 0 01 0 SET FROM 12 FT TO 22 FT TYPE DIA SLOTGA

SET FROM FT TO FT

4 GRAVEL PACK FROM 10 FT TO FT ATTACH ADDITIONAL SHEETS IF NECESSARY 22

5 BACK FILLED WITH trii fr• 2 TOTAL DEPTH OF WELL Renton 22 ft FROM 4 FT TO 10 FT DEPTHS TO WATER 3 23 PRODUCING FORMATIONS 6 SEALED WITH Cement FROM 0 FT TO 4 FT STATIC WATER 4 FROM FT TO FT LEVEL Ft below land surface

7 DISINFECTED WITHNA 5 YIELD gallons per _ min _ hr 8 USE OF WELL 6 DIAMETER OF BORE HOLE 65 IN DOMESTIC COMMERCIAL _

13 IRRIGATION _ PUMP REPORT N A MONITOR A I LIVESTOCKPOULTRY _ TEST WELL _ TYPE PUMP SUBMERSIBLE _ TURBINE _ J ET _ OILGAS SUPPLY _ SEMIPUBLIC _

2 SETTING DEPTH FEET PUBLIC SUPPLY _ OTHER

3 BRAND NAME AND SERIAL NUMBERS AC HEATPUMP TYPE WELLS SOURCE _ RETURN _ CLOSED 4 RATED CAPACITY LOOP _ gallo ns pe r minute

9 For AC only Will also be used for 5 TYPE LUBRICATION system purposes other than Heating or Air Conditioning 6 DROP PIPE OR COLUMN PIPE SIZE If yes name use yes _ no_

7 WIRE SIZE 10 For AC openloop Into what medium water

only is returned

8 PRESSURE TA NK SIZE MAKE MODEL 11 REMARKS

9 DATE OF INSTALLATION OR REPAIR Flush mount surface completion

AWD1 JAN 89 Arkansas Water Well Conslructlon 101 East Commission Capitol Sulto 350 Little Rock AR 72201 AC15845

COMM I8SION COPY STATE OF ARKANSAS REPORT ON WATER WELL CONSTRUCTION PUMP INSTALLATION

ETTL A 1 Contractor Name Number Engineers Consultants Inc C 1401 10 Thomas Cook LOCATE WITH X IN 2 Driller Name Number L2418 SECTION BELOW

3 Pump Installer Name Number Pff Nov 3 2 0 0 9 4 Date Well r New Well Completed Replace or Workover _ 5 COUNTY 6 FRACTION 7 SECTION 8 TOWNSHIP 9 RANGE Benton NE of SW V4 of 8 T1 8N R33W

LONGITUDE LATITUDE

o 11 94 31 280 11 36

DESCRIPTION OF B1 FORMATION DEPTHS IN FEET ®1 LAND OWNER OR OTHER CONTACT PERSON

B2 FROM I TO NAME AEP

STREETADDRESS 21797 SWEPC Plant Clayey Sand Red Tan 0 25 Rd CITY Gentry AR 72734

2 CASING FROM 0 TO 15 W 2 ID FROM TO W ID TYPE CASING pvC

3 SCREEN

TYPE pVC DIA 2 SLOTGA 001 0 SET FROM FT TO 2 5 FT TYPE DIA SLOTGA

SET FROM FT TO FT

4 GRAVEL PACK FROM 13 FT TO 25 FT ATTACH ADDITIONAL SHEETS IF NECESSARY 5 BACK FILLED WITH Bentonite 2 TOTAL DEPTH OF WELL 25

It FROM 3 FT TO 13 FT DEPTHS TO WATER 3 PRODUCING FORMATIONS dry 6 SEALED WITH Sament FROM 0 FT TO 3 FT STATIC WATER 4 FROM FT TO FT LEVEL Ft below land surface

7 DISINFECTED WITH NA 5 YIELD gallons per _ min _ hr 8 USE OF WELL 6 DIAMETER OF BORE HOLE 65 IN DOMESTIC _ COMMERCIAL _ IRRIGATION _ PUMP REPORT NA MONITOR LIVESTOCKPOULTRY _ TEST WELL _ 1 TYPE PUMP SUBMERSIBLE _ TURBINE _ JET _ OILGAS SUPPLY 0 SEMIPUBLIC 0

2 SETTING DEPTH FEET PUBLIC SUPPLY _ OTHER

3 BRAND NAME AND SERIAL NUMBERS AC HEATPUMP TYPE WELLS SOURCE _ RETURN _ CLOSED LOOP 4 RATED _ CAPACITY gallons per minute

9 For AC only Will also be used for other than 5 TYPE LUBRICATION system purposes Heating or Air Conditioning 6 DROP PIPE OR COLUMN PIPE SIZE If yes name use yes _ noD

7 WIRE SIZE 10 For AC Into what medium water

openloop only is returned

8 PRESSURE TANK SIZE MAKE MODEL 11 REMARKS

Flush mount surface 9 DATE OF INSTALLATION OR REPAIR completion

10 there well the Is an abandoned water on property 12 SIGNED DATE

AWQ7 JAN 89 Arkansas Water Well Construction Commission 101 East Capitol Suite 350 Little Hock AS 72201 ACI5945

COMMISSION COZY STATE OF ARKANSAS REPORT ON WATER WELL CONSTRUCTION PUMP INSTALLATION

AWO7 JAN 89 Arkansas Water Wefl Construction 101 Commission East Capitol Suite 350 Little Rock AR 72201 ACI5948

COMMISSION COPY STATE OF ARKANSAS REPORT ON WATER WELL CONSTRUCTION PUMP INSTALLATION

ETTL Contractor Name Engineers Consultants 10 Al Number Inc CL 1401 L 2418 I N 2 Driller Name Number Thomas Cook D SECTION BELOW

3 Pump Installer Name Number P

4 Date Well Completed Noy 2009 New 4 WeIIZ Replace or Workover J 5 COUNTY 6 FRACTION 7 SECTION 8 TOWNSHIP 19 RANGE

v4 of of

Benton SE 14 NW 8 T1 8N I R331d LONGITUDE LATITUDE 94 0 31 278 11 1 36 0 15 1 89 1

B1 DESCRIPTION OF FORMATION DEPTHS IN FEET D1 LAND OWNER OR OTHER CONTACT PERSON

B4 FROM I TO NAME AEP

STREET ADDRESS 21797 SWEPCO Plant Clayey SandTan Gray 0 23 Rd CITY Gentry AR72734 and Red 2 CASING FROM 0 TO 13 W 2 ID FROM TO W ID PVC TYPE CASING

3 SCREEN TYPE PVC DIA 2 SLOTGA 001 0 SET FROM 13 FT TO 2 3 FT TYPE DIA SLOTGA

SET FROM FT TO FT

4 GRAVEL PACK FROM 1 1 FT TO 23 FT ATTACH ADDITIONAL SHEETS IF NECESSARY

5 BACK FILLED WITH Bentonite 2 TOTAL DEPTH OF WELL

23 ft FROM 3 FT TO 11 FT DEPTHS TO WATER S PRODUCING FORMATIONS 23 6 SEALED WITH C emeritFROMFT TO FT STATIC WATER 0 3 4 LEVEL FROM FT TO FT 75 Ft below land surface 7 DISINFECTED WITH NA 5 YIELD gallons per _ min _ hr 8 USE OF WELL 6 DIAMETER OF BORE HOLE IN 65 DOMESTIC _ COMMERCIAL _ IRRIGATION _ MONITOR 0 PUMP REPORT NA LIVESTOCK POULTRY _ TEST WELL 1 TYPE PUMP SUBMERSIBLE _ TURBINE _ JET _ OILGAS SUPPLY _ SEMIPUBLIC _ 2 SETTING DEPTH FEET PUBLIC SUPPLY _ OTHER

3 BRAND NAME AND SERIAL NUMBERS AC HEATPUMP TYPE WELLS SOURCE _ RETURN _

4 RATED CAPACITY CLOSED LOOP _ gallons per minute

9 For AC Will also 5 TYPE LUBRICATION only system be used for purposes other than Heating or Air Conditioning 6 DROP PIPE OR COLUMN PIPE SIZE

If name use yes yes _ no

7 WIRE SIZE 10 For AC openloop only Into what medium water returned

is 8 PRESSURE TANK SIZE MAKE MODEL 11 REMARKS

9 DATE OF INSTALLATION OR REPAIR Flush mount surface completion

10 Is there an abandoned water well the on property 12 SIGNED DA TE

lov•

AWD7 JAN 89 Arkansas Water Wolf Consiruclfon Commission 101 East Capitol Suite 350 Little flock AR 72201 ACf5945

COMISCIOC03Y COVIRACI •OUVIWESIER EEECTRTC POWER COVPANY iACHEN CONSTUCTTO COIPANY FLINT CREE POWER FLAT SITE WORk SEPIEXBER 4 1974

OWNERS COPY This agreement made this 18th day of Febrpr 1 975 by and between

Machen Construction Com n hereinafter called the Contractor

Little Rock Arkansas and Southwestern Electric Power Company

hereinafter called the Owner

W TNESSET€

contract is to be Marhen 1 This performed by Construction CREPaan Contractor within the State of Arkansas and the parties hereto covenant and agree that it is and shall be construed as an Arkansas Contract in accordance with the laws of the State of Arkansas and the parties hereto shall have all the rights privileges remedies and immunities applicable under the laws of said State

2 Contractor agrees to complete the plant site clearing grubbing and grading railroad bed construction ash pit dike construction and related work and excavation and embankment for the Generating Plant area as set forth in the Specifications at Owners Flint Creek Power Plant site located in Benton County approximately two and onehalf 212 miles southwest of Gentry Arkansas

3 Contractor agrees to do the work in accordance with the Specifications and Drawings attached hereto and made a pert hereof Any changes is the Specifications or Drawings will not be a part of this contract until ordered in writing by the Owner

4 Contractor agrees to furnish in good operating condition all construction equipment tools and supplies necessary to complete the work in the time set forth in paragraph 6

5 Contractor covenants represents and warrants

That all applicable provisions of Executive Order No 11246 dated September 24 1965 the Rules and Regulations promulgated thereunder by the Office of Federal Contract Compliance of the United States Department of Labor and all applicable requirementsof the Equal Employment Opportunities subchapter of the Civil Rights Act of 1964 have been fully met and observed in respect of the manufacture of the materials and equipment or the performance of services covered by this order FLINT CREEK POWER PlANT

SOUTEMESTERN ELECTRIC POWER COMPANY

These specifications cover the Plant Area clearing and grubbing plant site and coal yard grading ash pit dike construction and related work railroad bed construction excavation and embankment for generating and other plant area work as per attached drawings and the following specifications We have attempted to list all major requirements of construction and any requirements not specifically covered by these specifications andor drawings but essential to the accomplishment of this project as proposed herein will be considered a port of the contractpsice to satisfactorily complete this job

Drawings will show the scope of the work All such drawings shall be considered as a part of these specifications

3 INTERPRETATION OF DRAWINGS AND BIDDING DOCUMENTS

If any contractor contemplating submission of a bid for the proposed work is doubtful as to the true meaning of any part of the specifications or other contract dortents or finds discrepancies in or omissions from the drawings or specifications he shall submit to Southwestern Electric Power Company hereinafter referred to as Owner a written request for interpretation or correction thereof Interpretation or correction of the contract documents will be mailed or delivered to each Contractor receiving a set of documents The Owner will not be responsible for any other explanations or interpretation of the proposed documents

The Owner through its inspector or accredited representative will have the right to make such changes and alterations In the quantities work be of as may considered necessary or desirable and such changes shall not be considered as a waiver of any condition of the contract nor shall they invalidate any of the provision thereof The Contractor shall perform the work as increased or decreased and no allowances will be made for anticipated profits Altered quantities will be paid for at the contract unit price

••+1rho Eflrrr S`FG•Frksa h`sh2•• beyond the control of the party affected including but not limited to sets of governmental authority acts of God strikes or other concerned acts of workmen unavailability or substitution or diversion of labor or materials and operating equipment fires floods explosions riots war rebellion and sabotage but the foregoing shall not be considered a waiver of either partys obligations under this agreement

The said Contractor shall take proper means to protect the adjacent or adjoining property or properties in any way encountered or which may be injured or seriously affecte3 by any process of construction to be undertaken under this agreement from all damage or injury by reason of said process of construction and he shall be llable for any and all claims for such damn on account of his failure to fully protect all adjoining property The Contractor shall be responsible for the protectionfrom damage by fire falling trees or any other cause resulting from the contract work of the property crops timber grass livestock fences gaps gates cattleguards buildings or any other assets of adjoining landowners The Contractor shall be responsible for the repair of such damaged property and shall make repairs without delay

The headings of articles sections paragraphs and other parts of the contract are for convenience only and do not define limit or construe the contents thereof

A Purchaser agrees to pay the Contractor monthly as the work is completedbut the total of such payments on account shall at no time exceed ninety percent 90 of the mutually agreed upon value of the work completed B Ten percent l0 upon completion of work and accept C owner shall fPrnish engineering required to determine quantities for payment 24 PiiOfECTIOtI OP BENCHMARKS

Benchmarks stakes marks etc shall be carefully preserved by the Contractor and in case or careless destruction or removal by him or his such employees benchmarks stakes marks etc shall be replaced by the owner at the Contractors expense

Whenever the word Engineer is used in this contract it shall be understoodas referring to the Owners authorized engineer or supervisor anstess specifically noted otherwise SOB SPECIFICATIONS FOR ASH PIT DIKES FLINT CREEK Pam PIMT

Tc coal fired will ar plant require area for storage of ash A fortyone 41 acre pit will be utilized at a settling area for ash A smaller pit will be used as a secondary settling area The effluent of this secondary will then flow into the main lake

This specification will cover construction of the containment dikes the cicaring primary and secondary settling basins building the interconnecting canal and excavating within the secondary basin Cross sections of the dikes and interconnecting canal are shown on Areas to be FCX3 excavated or filled are shown on FCX4

This will alwT specification the placement of temporary culverts under the dikes and construction of a arllway connecting the secondary ash settling basin to the lake as shown on Drawing FCX 4

I M IN JOB SPECIFICATION

FIINr CREEK UNIT 1

SOU TJI WESIERN ELECTRIC POWER COMPANY

ASH PIT DIKES

SCOPE OF WORK

Construction f ash p3nd DTScFS including clearing grubbing placing cimpacted fill structures in dike pipes through dike Wier box complete by 3thers

11 WRK F3RNISHED AND INSTALLED OR P£RFOf4tFJ Contractor shall furnish fabricate deliver and unloadmaterials and equipment for shall store prAect and remive materials and equipment from storage for and shall install construct erect or perfom and finish the following WORK

a Earthwork including eleE g and grt 1ling excavation backfilling filling and soil compaction contr3l

b Construction of earth dikes along the sides and within the ASH Storage Area

c Hiscellaneus Construction including concrete work metalwork carpentry work and galvanized corrugated metal pipes

d Orass work including sail preparation seeding fertilizing and eaaintenance

e Bedding courses and riprap as shown on the drawing

12 R1 E NSTBIL11Y FOR RESTRICTION OF NATURAL DRAINAGE IXRING FILL PLACEMENT

Contractor shall nit place any fill for dikes etc across routes of natu=ral drainage until previsions are made to drain surface runoff into drainage ditches f>rming a part of the WORK

No surface ri+niff shall be ponded ar restricted t a greater degree than would have occurred naturally either before the beginning of constraction Or after eompletion 3f the WORK unless approved by Purchasers repreeen tative

Sh3uld pnding or restriction f surface runoff result in water being backed up oont prjperty not owned by Purchaser or onto Rrrehasera property where work by ether contractors is either under way or completed or where materials or equipment are being stored all damages resulting therefrom shall be responsibility of Contractor

Temporary Slwpes Temporary construction slopes in excavation or in flU used for temporary drainage channels shall not be steeper than 3 horizontal to 1 vertical except as indicated on the drawings or as approved1 211 SECT10s scot it111 This section of the includes foiling as Specifletation reguir•emefnta for the indicatad on t•e under drawings ss hereinafter the Article numbers specified indicated or as required Mete the WOidt to properly

212 Services of Thsttng Laboratory 213 Soil Data and IbiaograpiW 21k Henwmlof Sod and Thpsoil 215 Excavation 216 Compacted pin 217 Equipment 218 Fill placewnt 219 Backfill 22110 aratiaan Fill for 1 Corrugated Metal Drainage Ditches Piping i2 course 22113 er for Riprap

pRip 2114 trading 2115 Seeding

212 SER lcES CW TESTii4C MD€Rti y hill be ftsrniehed r Purchaser Tor use in connection avraiaecttd with controlled Willy as specified fn Article 62 of Form 171k SOIL DATA AND nMr bar Ass specified in Article 2 of Eons 1714 borings vi11 be Drawings are included and bits avalilable for inspection at Associate Inc S6JEPCo or Stewart

2114 R AL OF SOD AND TOPSOIL alas specified in Artie1FT6 of Fora 1714 10213site vtaere and as Stockpile topsail on requested by later Rrehasere reuse Dispose of sod representative for on asp representative requested by Purehuers

215 AVATio

2151 As specified in Article 5 of Fore 1714 aaaeraU on Dispose ofan excavated site either as fill maters am ax 1 or in 2equested by Purchasers aatockpile ages eateavauam res shall be based e a t on a free Sul distance p red to of 200D ee i at in thet t t dirt excess Of the 2000 O beven mat fay •t foot free haul diatt a iIl L r•• 74 quarter ass sae Item 140 g Overhaul of the t4ei to he by 1972 Texas Hi hwa referenced as he S Y •5tar it governing s a• for 600 few jr ctfictiara 0 s haul a Th0 fray i is stanceiBpi caton in It loot 1i fiesrt• 1 flfeian the 0 ppro a Eimer mast be e obtained beforet 4n • payment will be made for • tNSIMECIVS =00400 0

2152 Area nf st rkpiZ =hall as be eleQnetl specifd in of ve Uetation+ Article 4 and disposed S of Form 1714 of 2153 As specified in Article insiicntecl on the 53 of Fonn deli is 1714 and as Clnkr ctnr drawings turinf shalt maintain couxse of the fill sufficient WORK erea t Permit slop in a drainage of excavation and on dry w a t ex orking cditionon adin mantaining 2I6 2LIpiCiED FlLi

2161 C€rnirtt• to the applicable mid o requirements hereinIfter Article 6 of Form sPecified 1714 2162 Class F j One of the follo•ain an indicated on the a Class _lxavinge 1 Regular Compacted Fill 1 roe RCF1 b G=anular Material Class 1 Regular C paeted Fill Type RCF2 Cohesive a Class 2 Material Controlled ComPacted Fill Type CCF1 Gran uYax d Class Material 2 ContxaLted Compacted Fill Type CCF2 Cohesive 2163 Hater Material i al Shall be en impezvious fill borrow areas material obtained on site as from apProved indicated ot the excavation ytoekpiles or drawings borrow areas or from fill shall he off site Alingor designated a dikkeer and a of e tative The fill h sege material Purchasers r shalllnotnot or meir gar than anny repesen•rernine inches any cobbles or b= 9 nches ken plarernent and maximum dimension compaction at time of

compac t 1n Densitis Dike fill Dyersrs nRE shall he loosel exceeding ten Y Placed in be lo inches Each zrtghly corn Isyx of fill means of sha 11 Fnevratic tired rollers a clreepsfnot of roller or dent a ver to capacity and nes obtain not through Suff

I1idi et less i rind Proctor than 90 PexCett densitynsit in of the edi ti accordance maximum Kra with ASTT Test D1557 latest 2155 P=j yni n 011wnic Materials ratr•r irei Vrreterinrr organic er rerrol i an n3 in PreparaEinn ald Articles rvecnof ribgrade iSpsied Mats633 an as K432 li••s Of on the site3 of Form ite as 17th shall he requested by PurChasers 2166 1 representative mMLIrara i njj Prior tt aftert =zui3r•= placement of strilrpngF the iil shGrade shall material and rrrh srrficient be Compacted of Passes of Proafrolled densit•rint the 1ps£ troller the present surfaceIpp capableca m°r r m less Hodified Proctor percent

the density in aceoxthanmince with AB3M Test 217 EWL

2171 oespaction Equipment Equipment to be used for Y consist `strucEilg fill of any type normally considered suitable to embankaaents for tiaras or construct highways Main compaction including heavy pneum tic equipment tired rollers vbratpry sheepsfoot rollers compactors shall be subject to representative approval of Purchasers

IL In addition to the foregoing equipment the Contractor shall have following equi pxtent available at the WORK

a1 Power tampers to be used for com acti on Where it p of material in dress in prsctical to use a roller or tractor

a2 A plain cylindrical roller weighing not less than punds lineal 1000 per foot for rolling the smooth surface of fill for drainage in case of heavy precipitation a3 Discs harrows and motor graders for fill drying and maintaining

218 FIIi PLACII4P A T

As specified in 645 of Form Paragraph 17140 and as foilms as Distribution and gradation of materials th shall be Such roughout rolled ttrat fill W i ll be free streaks from lenses pock et or layers of material s differing in or gradation materially texture from surrounding material and Combined excavation placing operations shall be such that materials when oompncted in the fill Will be blended to the best sufficiently secure practicable degree of compaction and stability Travel on the fin shall be satisfactorily controlled to prevent tracking or cutting fill

Successive b loads of material shall be dumped no as to the best produce practicable distribution of material and for this purpose locations in earth fill where individual loads be deposited shall may be designated If the of surface of any 1ayer material to be placed thereon has formed a hard crust from overcompactedtraffic it shall be moistened moistened and or both scarifiedas required before of the succeeding layer material is placed

c When rain is expected and at the end of shall each working day fill be rolled with a plain cylindrical roller to form smooth surface with a sufficient slope to cause rainwater rapid runoff of Before resuming placement this surface shall be scarified and moistened as required If Purchasers representativedeters that the rolled surface of any layer of earth fill in place is too wet for proper compaction or ria theram It shell be removed allowed to dry or shall be worked with a harrow scarifier or other suitable equipment to reduce water content to the required amount and then shall be recompacted Ao not place the next succeeding layer or rill until approval to procned is given by Purchasers representative and the Consulting Engineers

d All oneninge through embankments required for construction and tempnrrlr drainage purposes shall be subject to approval Approach or construction ramps for dikes and embankments shall be rtatoved and those on the outside face shall be removed andor tr1umd as requested

2191 An specified in Article 7 of Form 1714

2192 Material shall be same as indicated in Article 2163 for Compacted FiR

2110 1XCAVATIOIt AND FILT FOR CQARUGATED METAL DRAIN PIPING

As specified in Article 9 of For 1716

r 2111 Ilr iNAG ililCt

Cut andor fill drainage ditches if required to cross sections and profiles indicated on the drawings All surfaces absll be reel compacted a Riprap shall consist of qparried fraR stone or other Structural defects atone free and of approved containing shale unsound quality gandstone or which will anY other maStteriaveal readily disintegrate under handling and weathering shall not be used placing or Any stone which Incipient fractures is free frog and seams and has to withstand given evidence weathering after of ability shall be long exposure to the cnsidered suitabl elements e for thi s of purpose Upon presentationsatisfactory evidence of such stone ability to withstand may be used without weathering laboratory testing b In case newly quarried atone or stone of quality is questianable proposed it shall tie weathering eubjected to the sounrlntsatest and shall show diwn Sulphate a ass a t han 25 percent ft er cycles of not materials failing more f when s this t t may be iubJected to fifty appro 1 has a lass cycles of freezing and not greater thawing it than 25 Percent Soundness method £88 Method Use 1004S•diiM of Test for

bM Soundness um Sulfate or of of Test Magnesium Sulfate or MMethodte for Soundness of T103 Aggregates by shall be used Freezing and Thawing

e The mist unitweight of shall riprsp not be leas pounds per cubic foot than 164 21132 Size and Gradation

g RiPrap shall be 1 reaeonrz uw e l l aghall graded and quarried have a gradation stone conforesting to the limits fallowing weight 21 a1 Max1m site lb a2 At least 25 450 percent greater than 200 lbs a3 45 percent 75 percent from to

ae4 Not more than 25 percent less than 50 lbs a5 Sark and s rock dust not more than 5 percent b The shortest dimensi 0 anY St shall 13 of the be less than longest di mension for at least 60per

per cent of riprap For the balance th the 7 E shortest not less dimension shall than 15 of the be longest distension C Alternate sizes and gradations will be WORK if considered for the they will achieve the desired performance cost If an alternate at less is Proposed size alternate shall be and gradation of stated in the Bid with the Proposal price saving together 21133 placid

a Riprap shall be placed by dragline clamshell or similar eofquipmentmateriwhin so as to alchappzoi ahalxlftnbeoperatedatelY glace each load its final Vsrther ze rking and position without without excessive height of drop b Placement operations including handling transporting shall be stockpiling and accomplished in produce a such manner so reasonably well grad d as to percent mass of ruck with age of voids free minimum from objectionable Stones and clusters pockets of of large stone small regular finished having a surface r0asonably

c Piprap shall be placed on the and fsee of the grades and to dikes to the l the minimum thickness drawings The indicated on themes riprap shall be thickness placed to this In one operation full minim the minimum Thickness not be at anyy point less than may be placing to a limited

imu ired n extent to the extent results necessary to specifiedpacified foregin secure

d In no case shall a bulldozer be aged in slopes shaping the riprap 2114 C NG

As specifisil in Article 8 of Form 1714 and as drawings indicated on the

2115 3kEDIHG 21151 All slopes and surfaces as indicated on seeded as the drawings hereinafter specified shall be

a Materiel Approved topsoil from and stockpiled topsoil Previously on the site or excavated off the approved topsoil from property or both sources

b Placing b1 Spread topsoil evenly to a depth which after elmpaction shall be 4 settlement and inches not or topsoil is ground excessively vet orotherwiseein dcttimental to anyncondit the work if on hardened or existing surface has becme crusted rake or otherwise bond with break up to layer of topsoil provide

b2 After spreading has been completed rake clods stones up and remove lazger than 2 inches in large r RUMPS and other any litter or dimension mots deleterious material b3 C rpleted finish grading shall provide a smooth indicated grade true to elevations cross sections and drained and free from profiles approve or high for spats and as approved subsequent fertilizing and apecified seeding operations as her+aftar

a Material Headynixed material having an nitrogen analysis of 1688 available phosphoric acid and water soluble Deliver to job in potash sealed containers with name of weight analij isr manufgeturer clearly indicated on each container b 5tor Store e in such a manner as will not i effectiveness mix Tertilizer r o

c Cover e 301 21151 lbs per acre

M Seeding Time 1b fertilizing and after seeding as soon as completion of finish topsoil work tauever do r seeding no during windy weather or when or inertfngan otherwise ground is wet untill ba le condition b Seed

bl Seed shall be unHulled Bermuda and Re with Purl tv and a Y grass

b2 Coverage Berrizud 5 Lbav per 1000 SY Rye 21 grads lbs pO3 1000 b3 All seed shall comply with all appIicable laws and of the State regulations ollirkansaa and of 11 S Department of Agriculture C Have seed delivered to Job in sealed containers

d Furnish ti Purchaser duplicate signed vendor copies of statement seed

that by c•

each 5Y lot of see d has been tested by a recognized for seed testing laborAtorywithin six months of date of and delivery complies with all requirements for the specified seed e °twon Immediately after see di ng cover seeded tons acre areas w i th trap 2 per of straw mulch and anchor t h is asphalt by spraying with cutback AC3 at the rate of 1D gallon per Sowing and Maintainin sq yd fert4lizinr Of seeding eprinkkirt g as required will be at option of Contractor Work gansidered shall not be crsplete until after a uniform and dense stand of healthy grass has been produced in accordance with free from these base spotty and apecifiaatiovs gullies forted by accepted in erosion and when writing by Purch seer SOMIMESIERN ELKJA1C R 22 PANY FLINT CREEK PQiER PLANT UNIT 1 DIVISION 2 bCIINICAL LI EWIREMENIS

SEG11ON 2Z CLEARING ANDGRUDfING

221 SECTION SCUPS

2211 This Section of the Specification includes requirements for the ing as indicated on the follae drawings as hereinafter specified Article numbers under thl indicated or as required to property complete the W01 2212 Requirements of Division 1 General Requirements also WORK under this Section 22 apply to the

222 2REE r + 1tEHDV ND CIEAgJNG

22 21 Conform to applicable requirements of Article 4 of Form 1314 and to requirements hereinafter specified 2222 Tree Removal

a Clear and grub all trees in the following areas 1 Dike horrow areas

2 Within the toes the entire base of lake and ash pond dikes I All other trees within the lake and ash p ond dik es sh211 dozed at ground level be ahtiarr

C Remove and dispose of off the site all partially buried timber logs down snags brush hedges bushes and all other vegetation or organic material all rubbish debris and other foreign or objectionablematerial above ground surface

d Remove all floating debris in swampy areas and Cut dispose of off site all trees i n swampy areas asrecteddi by Owners Engineer

2223 CLEARING

a Contractct shall have full property rights to all timber cut and may Off by him sell the stte only all merc h cuts antable timbhiher h rchantable t€mbor he wce may processed either on the site Off tI I as or to agreed to with l4lrchaset but shall li be from the site before removed h cimapietion of th e WORK 2224 ESilmyEED 54 UAtiItTy acres clearing 12 acres clearing and grubbing 2225 FOR HA•i9 PAyMEVp price per acre curing Price per acre clearing and Stubbing SI€rtsD141iO ETSPECIFICATION FOR

Form 1714

GENERAL Il Earthwork shall conform to fic the r Earthwork the of lob S requirements this Standard variance pacification and the

Specipecifibe design een this Standard drawings In the Lion or Specification event design drawings and the Job shall the lob g Peczfic$ take precedence Specification and the 12 design drawings Where the terms as indicated or Specification indicated they shall mean s$e i n this as shorv Standard specified n noted called forf or 13 All references to the each following together publicat ions are with the to the latest of h latest issue of tdatethe of additions andor Contract unless amendments ri otherwise thereto as sng agencies will Indicated indicated be made in references to the accordance with the abbreviations 11 1 ASTf American Society for Standard Testing and Materials Specification

erican Standards Association Specifications Standard

American Association of State Officials Standard Highway 2 Specifiicatons TA AND TOiRA I 21 Sail Oakes braerings show bori indicatendicate made at character of site and soil This logs given theon in information furnished using it Contractor for Contractor`s Consulting assumes the Engineers assume risk as tiara no Purchaser shown thereon responsibility for the Contractor will be accuracyeeraey orna investigations but Permitted to make same shall be his ownn made at no soilofl 22 cost to Topography Orawi Purchaser rags profiles indicate and contour elevations dimensions lines of andor cross for Contractors existing sections convenience in usiground information Purchaser atheandn using it Contractorctor furnished chaser Consulting assumes the of n$ Engineersngineers risk as n hown assume no thereon responsibilityresponsibilit for investigation Contractor will be of permitted no topography to make his cost to during bid period but we own Purchaser ewe shall be made at 3 LINM AND CUES 31 Coc•ractor shall lay out lines and msrrkm on prshal grades from y and be fully existing base lines and grades Y responsibleponsible for and bench

spd fyr correctness proper execution of of such lines iiogi to such lines and grades 32 Purchase reserves nigh to progress of verify correctness iRRK Such of lines and grades d tractor of verification by axing res Purchaser will pnsibiliy as specified not relieve 3 foregoing t shall notify location Consulting Engineers

Qor£ of exfsting work any differences Con3may from that in affect Indicated new work wherever such 34 differences Contractor shall preserve and established by Purchaser marksks anda maShouldintaitnxaaclltbench reference or Canar ints ecIIFpvemove• bench during prosecution WOP marks anrrJar of o the c0st reference marasant Purchaser points andor of establlishcd by reference reestablishing paints will be these bench marks dbcharged to Contractor 4 CLFARjm 41 Prior to FerfoYmi ng is excavation or to be done fill shall be work areas in NO cleared which such clearing p and the work grubbing or soil and side removalgofbtop sod designated and areas sadtoo shall be without specificaparl doner•out 2 if approval extensive cleari ng grubbing and quirede the removal Job Specification of top soil and if sod is pa archsuch waeic i drawings will d ficaor specifically sfasu nt then it will so performed not be s prior to but l 43 as part of indicatedndicated and a4Clearing excavation work 431 Clearing is d8ined as r snags brash hedges busehsaand dwn and also all alliotherlvegetation rubbish debtto oror tfmbt above or ocher g•artiaan •eY3sls ground surface foreign or except removal objectionable 412 of sod and materials gemoal of top soil structures such as Classified as buildings demlition and adwaYs fences the Job not as cleariro Specification under and wwill be Demolition Work Ord indicated in 433 Work on Trees shall be dryings filled in such taeia manner as not to remain damage other trees facilities in or other ng 44 life structures and Grubbing Grubbing is r+$ defined as large root$ removal and burled logs and disposal of all ground all other stumps surface objectionable and Explosives may be material from below their use shall used only if conform to all spetificsll a 454 Disposal applicable laws and safetyy ronsre$cruladati 45°I All materialsal from clearin g and

pxop to and grubbing shall be operations shall be indicated of Contractors in the job off the site S•eci•fication•red unless otherwise materials on on draaims premises not s 452 permitted accumulation of such Burning of Debris on Premises mitred b If by the Job burning of debris on Specification premises is requirements drawings axrchaser conform to fallowing 4521 Burn debris only in areas speci€ically designated by Purchaser Aft

4 5 2 2 Prior to buxti n$ any a and c 1 secure °I2 with all o approval and bodies regulations of PermiCS fry having all authorities Jurisdication in and all 45 2 3 area of Public Aleat 1 VRg Y Mile all Combustible condition material Do and bu rat piling in such he in cause least manner fire rise 4 524 Burn material and reduced to ashehorou ly ith completely so that no chaxred materials are remaining A pieces and such as charred buStib coal residue hess need not be rlags cha d Clumps he burn such Coi mmy buxi as tree eStumps cover over armed grade and roOt them bellow with not less eve with thenn ItOf0 of required for surron 3i the •iig if grubbing is required then all a 525 disposed of such fire Protection off the Provide PR•e•mfsea authorities fire fighting having Jurisdiction facilities facilities anda to f as first Purc•aaer class and maintain cho burning operations operating c0ndit4o os during course 4 6 of Reeoval of Top Soil and Sod 46I rop sail and sad the shall be Job removed °f Specificetfon or drawi excavation shall be track unless Yeaaaved indicate that and stored forgs to 462 If reuse by and top Soil is Contractorr oor bybr OtherOther 1zdiaated to be e stripped remav for off snored in roue it X11 fore sepaste shall be i gn stockpiles and carefully the material and kept clean top soil ateria other andfree of ir vegetation shall be Sad stockpiled removed from 4$3 if sod is indicated to be removed moved called for reuse up and it shall be as stored in a CarefalL approved suitable and Y re well protected r manner 464 If top soil andor sod is and all indicated to exc s stock be reused b pil es y Contract wed and remaining 071 or dinPosed of completion any off the of shall bey Premises unless re 5 FATI otherwise requestedr 51 fora i s defined Eradisposvat to include and alof all excavated incidasetal cleari bracing and materials all all pxotectir•n excavation as coffeid all sheen required to dewateri and horing preparation install and of bearf qono properly complete areas which the WO encountered rewired and excavating regardless of nturelof htein Dredging Specification shall be materials or on the performed onl if 52 drawing Y specified Classification Excavation as follows shall he classified as earth or rock 52 I ° Earth excavation Sxc soot lass Is all 522 a•atericl not Rock classified as lcevatlon rock excavation

522l 1tock excavation defined ttnuous drs as use of any material that and and blasts requires the shall include ng or con granite drilling s Leap channeling etc $tcsrte hard shale quartzite ahei oro slave limest ne Farm 1714 or other hard well as rucks and boulders 5 2 2 measuri 2 The I2 cubic Job gp yard Or cffic aticr or more Pe dram gs lI i icate oftted I$Iastir8 If whether 5 I1 Permitted Shall blasci following canfaren S3 to r•iire watering Contractor shall raga€r for In areas a a cavaed byroyntsae all dewateri dry site sa c or6perste equi LLefactory to and be intent Pizchaser responsible gor 54otection and Consalei maintain and Supart 1rg Zilg€neers 5AJ Contractor Shall provide all properlyy protection instalH tho and support aE the del as as reluir WORK and of required for to gored adjacent protection and for structures and im SapppY Lt of traffic rov 5•i2 and life ements and as pxotecgir=y resafety and shall Shoring and ferp include tempos and bracing an also where sheeting bracing sharing t4I1 indicated t rsr permanent cofferdam shall be sheeting as ffippemp ysheeting braeing r`ved by shoring and Ccaratrzctr when such wise its u temporary work requested or se is no shall be approved longer required A 3 unless ga at e3cc avaC ions or shall be other5where protected and rege>•ted so that the bales where d•+ jmt $tructur and bottomsbottpported accessary es or other will bbe dadaga taste construction maintained any will be earth or rock protectede 5 44 movement ed from rotagivrs and scspperzt pipe shsI be layip electrical arranged ductwork interference with 545 2 installation andgad Oporary Cofferdaans similar work Contractor by himh shall t•e4afreci to design ered perform his work temporary Ito and shall Cofferdams fob dr•vi submit drawl aped NO ngs shall show a

ffTh all work shall data on received be whichthetdesign and the work until approved sh all be dnetonled such a drawings yin accordancepwithathese 55 Egr eh excavations E0 ll be foirvark for of sufficient size to cOr concrete for allow for rote and inspection of Placing of oar d formwork and hs etc i9xoofing surfaces of Rack waterproof Trig completed exc$vations shall bet Pipeworks mere to neatat lines placedduct•icatedoVerbreak of rock unlessclotherwise against occura behind a as •k everbreak shall vertical face rewired for the beb filled concrete crate vertical with the Sam fill face and no concrete payment a Il be made for 56 avatf shill be carried follows to elevations indicated con°an dra3ri 5 fi I mss and as l4rt1z Ercavatou ftsuudat levell evel ion sell be filled with theexcavations below dation same the other earth ncrete°$sed be excavations ox btt~girt up to carried below f •• the the endicaindicated stone proper level with level gravel or compac shall concrete as fill rs determined crushed t tt band suitable by the Consulting 5112 FCck Ekcavatioxx lea designated reachee9 or approved rock surface elevations have shall be leveled been removed Where off and all ove rbre of loose rock roux k rock results in surfaces below dro pIng designated or elevations of $hall be filled approved with the same elevations overbeak concrete as 5 6 3 gc required for paYmesrt the will be made for foundations ec any remedy oil specified overexcavation in oreovefor fill r earth rb required Hid e a in rock excavaticionm shall be used If excavation adjac request ed for to structures trenching or other excavating or equfpeuent equipment is where use of not considered mechanical Consulting Ensineerv advisable by Purchaser or the 8 Bearing Areas SSi Bearing arrest for all € PtsrctiaserPu orations shall be or the C inspected and if chase onSulting ineers approved by bearing areas are before any not suft concrete is l sle as Engineers Contractor determined by the may be Consultingd more suitable requested to bearing carry paid for material such on the unit additionaleexcavationnwillebet price basis may also be set forth for the requested by the other Consults B iiima teats at n Engineers to make auger bearing areas to auger borings these tests will determine be paid for thickness of ever is on a unit bearing strakum set forth for price or cost this stets plus basis All wltich582formations shall be placed on skated or undisturbed soil unless approtee•d othe=rwise 58 3 Before Placingg anyaRY C be corerete for beams well tamped or slabs on fill the soil shall 5g4 Before placing any concreteoisoil of the on soil shall he mrwet with clean water immediately before 5 9 Excavation for Pipework and Electrical Ductwork 591 Make excavation for this work true so as to to $ rade provide full • profile and and alignment and normally excavate trencheesento may be matchtcurvesofepipeb wer used If as economical r flatc as curved beds indicated beds orshalll bee usedif 593 Whereere gxlar b in So b Spetranaruoar unPipework or ductwork is indicated in to place drawings excavate the the indicated the additional depth of amount required 510 bedding material Disposal of Excavated Materials 5101 Deposit and spreads or stockpile opinion of Consulting ineers required and for•filltornbackfillsin approved on quantequantities

premises es 5102 where requested For eavated materials not suitable for specification or fill or dringswill backfill the Job be disposed indicate whether of on oroff such material as premises and is to follows disposal shall accordingly be 51021 For such material to be disposed Of on Premises where on Premises 5PPrOved deposit or or re•tuestesi spread to 1714 5 51022 For such material to be disPosed remove this Off material as exeavatedof premises promptly material will not be a stockpiling of Permitted such 5103 After completion of fill and backff11 or or when approved excavated excess Workmaterials either on stockpiles or excess or in 510 2 for fofall the Prises egoing as spec± pied 511 Requirements for chaserchaser blasting If use of or blasting is Consulting a p d Engineers blasts Purshallconformrm to following 5111 Blasting shall be performed taken for only when protection of propel etc Caps or persons the work rpate other exploders props ty stored or Ox fuses shall inano transported case bey in same place in explosives are which transported dynamite or other methods of Location of transportation storage magazines tot prevent and in prevent accidents general precautions shall at taken of Purchaser all timer be o C c subject to ineers but approval e for anting Contractor shall any injuries to at all explosives Petsons or property caused 5112 by Rvery possible to precaution shall be preserve rock outside lines of extaken condition cavationbinss• destrat Blasting poasi indicated shall be done on only to Imes and sibledrawings or as approveda grades by 5113 plosives Consulting Eftineers shall be of such in such locations as will notutend date rock outside tto openosealstdorhtolcrack

of prescribed limits of rsor firing blast shall ex on If be contzoiled Whenever b y use o€ needed

in of delay the opinion of delayed explosivesx Consulting blasting may injure ezs be rock on which continuation placed use or against of explosives an is shall shall be to beeompleted by dscontinueddiscontinued and means wedging boring excavation channeling or ether 5114 suitable Contractor shall submit plans and excavation work methods of before work is operation for rock blasting or started Approval of strength and of method of relieve amount Of Contractor of explosivesused Will not responsibility for 5 1I5 For blasts blasting Contractor shall employ a ep ienced in this supervisor type of thoroughly rigid work and shall inspection to at all times see that intent maintain fully complied of these with requirements are 5116 Contractor shall maintain a operat complete and ions in a detailed record of copies lTa blast such recordspto ues and shall Purchaserbasprequested submit

6i 512 Dredgpg

5121 Before submittal from°m bid Cant The U S actor shall from Army Corps of obkain them the eeping Full extent ngineers and shallaa3•o WORK of their the requirements detet•uzne as it 5122 will affect Contractor shall furnish• zange manes establish and stakes maintain gauges and in good sad buoys order all laborvor furnish on Yeuuitoed for and request proper the use execution andInd materials of such of crew used forming a park boats for this of the boatmeoatmen sulti work as Ordinar Y and

rrg Engineers may be usual and necessa for equipment 5 12 Corps of E Iurhc 3 C ngineers to s aaer C aontractorShall Peet workon to provide soundi so€erd and sweep Profile and dredged areas tored t ali went to estishgthatiabl and lobar 5124 are met Indicated As soon grade as Possible shall after tiusravgtel c•Pletion of y examine dredging deterffiine dredged r•oxk that area b u Contractor completed work i and drawings and all meets alla sweepied to requirements r equirements Arrang e with sPecifled indicated a n Purchaser for by Corps of ineers and Ongineers CaCorps of xepresentatives of sweeps is Engineers to be swee Performed present whenasoundionsulting fn Howeveg the now s9 presence and relieve of these c Cctkr of rea •lati oxt responigs tives 5125 of thethe wontw ili tp for c Anyy accuracy shoals lamps or the other lack foregoing ex of Contract nation shall dimensions again be he Iosed soundedau remediedemedied by by dre am and Y Cant r area as swept i f and satisfactory in required acterethe eulting 80gineers eve r3 espectuntal and Corps respect to Purchaser 5126 of Engineers Carer Contractor shall maintain approved by Consulting E record

ina ee ieand submit copies of such records bl Includes thpill the e usee ofa£ following two eaach shall classes with drawing be as indicated in under each the job S class Specificationpecif £11 Class or on 1 Regular the compacted fill 612 Class 2 Types RCF1 Controlled and RCF2 62 compacted fill Services of Types CCFl Testa L and CCF2 specified Where urchasseryillatory controlled determine furnish suitability services of gill is and to of fill a Testing perform material to Laboratory to field tests set o density to check moisture requlr•mentsents one

den iequiq Contractorr shall •plaancetwitmhn uaoistare andtents be quantities of fact rrn€sh used for the Testing material$ the Laboxatolyy with as required samee for test Source as purposesp will

Form 1714 7 6 3 Gass s Regular Compacted b3 I Fill two 539

llfiThe on the astfallarse Materials specifed foror Type lare use as RC$I Granular etc material sand crushed 6312 stone Type SCF2 gravel Cohesive 6 3 material 2reriai clap sand he 3ob loam of Specification silty laa rnaterfalst o be or etc the used drawingsas will site such as 0z from material indicate the material borrow prevfoasj source used pits or fxvm shall be as off site csvated at gngineees a PProved Sources by etc Ali 6 °33 baser andor Preparation the ofo Consulting st Subgrade striipp areas Prfor be to placi or covexed other of rer c foreign or vegetation acted 534 deleteriousl or otathter fill CmVac tIOD material genic Densities material required with guild u p fill suitable to Planing moisture grade ass c o elevations peci fi and indica capable of in 635 Coenpactian t or su fallowa±1i thx 6 PPoxtfrtg trucks ng Shout 35 P and other heats Produce a placing of completed fill Plane uctloll quested Pillas follows equi enC unless 5351 otherwise Pl ace Pod or fill To1irE1 not over 9ttoitable moisture deep content in 535 2 before uniform For Type 1•3 compaction horfsontal Sr$melar Paage of w heavy tractorsll compact by h her with successive brato treads high speed covering l 1135J of¢ For equipment as Type RCir2 approved aarea or orar with cohesive fill the compact ri by use of 6°354 IX• eheePs places equipment as foot rollei inaccessibles approved tF_ to mechanical large equi vibrators for pment obtain mechanical required raers for l compactioncost 6`4 Type •2Pe fill Class 2 cohesive and Control Fed e fill with Compacted 64 I The Fill two types are based as follows on the materials 6411 Specified for Type GC•I use as Cxanular fill

64 1 2 material Type CCY2 sand crushed Cohesive stone 64y material Sravei Material clay etc Conforms sandy loam to same silty requirements Iam etc specified in 632 for granular fil l

g 643 Preperet ion of Subgrade

6431 Subgrade td receive controlled co pacredfill shall be inspected by Purchaser or the Consulting Engineers to determine if it is suitable and has sufficient bearing capacity for the fill material d loads to be placed over it U subgrade is not suitable as deter it by the Consulting Engineers Contractor may be requested to perform additional excavation as specified in 5e for Bearing Areas with compensation as specified therein

6432 Prior to placing controlled c pacted fill strip areas to be covered of all vegetation top soil and all organic material or other foreign or deleterious materials

6433 TborouMy break and turn soil underlying the filled area to depth of 6 before deposition of fill material Do breaking of ground no more than 200 feet in advance of placing fill

644 Compaction Densities guild up fill to grade elevations indicated or with suitable moisture control and compaction throughout placing requiredin to densities as specified 645 following produce following

6441 Decidedly granular fill material 9OX of its maximum density

6442 All other fill material 952 of its Daum density

645 Placing of pill Place as follows unless otherwise approved or requested

6451 Place fill with opts moisture content in unlforw hnrisontal layers not over 6 deep before compaction Add water or dry out fill to aatntafo optima moisture content throughout placing and compaction

6452 For Type CCV1 granular fill compact by successive high speed passage of heavy tractors with treads covering 100 of area or with other vibratory tv equipment as approved

6453 nor Type CCF2 cohesive fill compact by use of sheeps foot roller or with other rites tvoe equipment as approved

6454 $a place is cessible to large equip t obtain required compaction with emcheciesi vibrators for Type CCFI granular fill and with mechanical roamers for Type CC2 cohesive fill

7 RACM

71 Saekfill includes general banckfilliug around all work excavated fot by Contractorand also all other backfill indicated on draeaings as by 72 $ackfill shall be approved materials previously excavated at the site or materials obtained from approved borrow pits and shall be free of cod or other deleterious or foreign setter

73 Sackfill shall be built up to the grade elevations indicated or required with suitable moisture control and compaction throughout placing in the saw zamwr an specified in 63 for Regular Compacted pill Types Cpl and

74 Backfill against foundation walls shall be placed only when directed

Porn 1714 9e $acEciill Around $rvund Underground p=pi Pipit drain Place backfill etc have be ins etc around onlyy after in andor nffi pipit drain undercarebackentested lines to see thai and oved materials Reich backfillackfi doe may be ll is fryroe serial such injurious of cinders FfXna drain I opinion or ether hard lines of Consulti or etc bard clods p lumps larger than kfi11 free of inciseshas Do xckrs an each ta3 not use Pipieg side Of drain lines sadd Place metal piping drain $ etc in drain age lines etc alternate pipee 68ckfill layers plate pipe corrugated around shall a structural corru gaged s6 la pipe or hackFill e$uirementplsate welded steel For Cartes spesi€i ed Bated and in fol 76 i Welded 6 loaairg There Steel gi flat beds Pipe for this dress i piping g$ Arae_id is flat indicated Job riding as lair S iWicaeeat bedding Pacification or a fill r on required by uaeauftabld pipe with salt i ondP greater depth once bedding fill as determined a l 762 byb the Granular Beddi ng Use clean ConmaterialWith crushed stone l12 or m=ice gravel 763 After else or other pipe is in approved fill place on uWer h flat bed Usn provide oro other clean controlled c appau•rsed•te crushed in +A acted mat e2 gravel granular 764 also ith 1I2 or coarse provide s mmi sand controlled compacted granular 765 fill u P to Fill Center line c center of line of alspt pipe aith and to controlled grade with 766 compaction select Controlled C material as for cnpaction shall Controlledl conform to impacted Fill requirements Laboratory specified Will also i in 64 be furnished and CCF2 foregoing for this Services of work as sting 767 Use specified in 62 extreme care in placing Proximately the both same levelnallotcompacted fill to sides of to maintain fill pipes exceed one foot at 77 throughout entire gackfill for placing of differential on 771 Ductruns compacted fill Regairer9ent of Standardtaredard be Specification used for E ductruns r103 that S1iaSllshall not clay or material loam b Provid may be used AnY 1 that for backfill approved previ sal ackfill averr d previously 7 72 else of uctr•uns tha For material shall t are precast not exceed leas concrete ductruns t ift tsa place than 2 provide thick on a of previous SIDES AM TOP with 1 washe a balanceawe elebac sand not cushion excavated material not of ackfill for precast 2t fill a pprov fork ductruns maximums or as as Pecifieexceeding rovided indicated on in lob e sand drawings S•aecificationnder Fu Concrete

10Agh MM UNGINeafts 1W Car4

7 Backfill in Roadways Where existing roadways are cut to install new work backfill such areas as quickly as possible after completion including testing if required of net work Bring backfill to 10 of road surface ready for installation of new roadway by Contractorwithinor by others as indicated in Job specification or on drawings

8 GZ IIG Consists of rough grading and finish grading as follows

81 Rough Grading Cut fill spread and level during course of WORK to elevations indicated

82 Finish Grading Fine grade and level to provide a sn oth finish grade free of debris foreign matter objectionable stones sloda lumps pockets or high spots properly drained and true to indicated elevations Do finish grading only near completion of WORK or when requested

AGL

Form 1714 Issue pate 71565 11 Final AREA UPSTREAM SLOPE CREST INSPECTED

MONITOR

INVESTIGATE

REPAIR NAME

i=O d w OF z GI

ADDITIONAL

DAM

2 z

21 19 18

4 23 22 20

27 31 26 25

30 29 28

35 34 33 32

COMMENTS

VEG WET

E CAVE

SLIDE

STAFF 77

WEIRS

REFER Little

DRAINS

SURVEY

EROSION

SEEPAGE

UNUSUAL

LOCATION

EMBABUT

Flint

AREAS

TATION FREQUENCY 7

GAUGE

ITEM

SLOUGH

OF ANIMAL

Creek

AND IF

CONTACT

MOVEMENT

MONUMENTS

CONTROL SCARP

PIEZOMETERSFOBSERV

FLOW Dam RECORDS 5

BURROW

READINGS

RECORDER

WELLS

APPLICABLE Z

kar •rv 2 t INSPECTED

rer

1L BY c 2 t ••

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c7• 1

EMBANKMENT < 1 1 o v

v ` l C e

OBSERVATIONS

s1•

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nFa•` S

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DATE 0

Ip w

17 CHECK

ACTION

NEEDED O a NAME a ut mA

w Q Z OF Z z Z J z

00 ua

DAM

Grl

54 53 52

56 55

61 59 58 57

62 60

65 64 I66 63

69 68 67

COMMENTS

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SLIDE

DEBRIS

REFER INTAKE Little

EROSION

Cc••n

STILLING UNUSUAL CHANNEL

APPROACH SIDEWALLS e

DISCHARGE VEGETATION

Flint

TRASHRACK

SLOUGH

ITEM

BASIN

FLOOR

AREA

NO Creek

CONTROL

IF STRUCTURE

MOVEMENT

CONDITION

SCARP

CONDITION

Dam

APPLICABLE e

os• • INSPECTED

of 1 BY

SPILLWAYS 3

•a•C

SP •

f OBSERVATIONS

INSPECTION

DATE a

z CHECK

ACTION

NEEDED

Lu NAME

0 ~ 3S O OF

z •• q

ADDITIONAL

DAM

70 z

81 76 75 74 73 72

80 79 78 77

83 82

COMMENTS

INTAKE

REFER

OUTLET

OUTLET Little

STILLING

PRIMARY

EROSION

UNUSUAL SEEPAGE CONTROL

TRASHRACK

SECONDARY

Flint

PIPE

ITEM

BASIN

TOWER

ALONG

CLOSURE IF STRUCTURE Creek

MOVEMENT DAM

MECHANISM

CLOSURE CONDITION

Dam

TOE

APPLICABLE

INSPECTED

OUTLET

of 1 BY

WORKS

OBSERVATIONS

INSPECTION

DATE

t CHECK

ACTION

NEEDED

EE NAME

U OF

ADDITIONAL

DAM

3 2 1 t 2 COMMENTS 11 7 6 5 4 10 9

15 14 13 12

Flint

LOW Ck

CAVE

RUTS

REFER

SLIDE

SLOPE

TO SURFACE

EROSION

SINKHOLE

EMBABUT

VEGETATION HORIZONTAL

AREAS Primary

VEGETATION

ITEM ANDOR

SLOUGH

ANIMAL

CRACKING

PROTECTION

Bottom

CONTACT

CONDITION

SCARP

PUDDLES

CONDITION

ALIGNMENT

CONDITION Ash

BURROW

Pond

APPLICABLE

v INSPECTED

of rti 2 BY

•

EMBANKMENT

cszR

OBSERVATIONS

g• V

INSPECTION

DATE f 0 •z N

CHECK

ACTION

NEEDED Lou NAME

z FD zai OF

ADDITIONAL

DAM

21 20 18 17 i

24 23 22 19

27 31 29 28 26 25

33 32 30

35 34

COMMENTS

Flint

WET

CAVE

SLIDE

STAFF

WEIRS

REFER

DRAINS

SURVEY

EROSION

SEEPAGE

UNUSUAL

LOCATION

EMBABUT

AREAS

FREQUENCY

Primary

GAUGE

ITEM

SLOUGH

OF ANIMAL

AND

Bottom

MOVEMENT CONTACT

MONUMENTS

CONTROL SCARP

PIEZOMETERSOBSERV

FLOW

RECORDS

Ash

BURROW

READINGS

Pond

RECORDER

WELLS

APPLICABLE VEGETATION

P•o 2

INSPECTED

••

of 2 BY

••

EMBANKMENT

OBSERVATIONS 2

e •a T

INSPECTION

6A6 v

DATE

0 z

P CHECK

ACTION

NEEDED

U1 z g DROP ERODIBLE m NONERODIBLE 0 INLET CHANNEL PRINCIPAL CHANNEL INSPECTED NA NIA 0 m wcy 10 ITEM NO m X 0 0 0 z C 0 z 0 a O z

rAREA

MONITOR

INVESTIGATE

REPAIR NAME

0 OF a13 w

ADDITIONAL

DAM

71 d

73 72 70

81 80 79 78 77 76 75 74

83 82

COMMENTS

Flint

REFER INTAKE

OUTLET OUTLET

STILLING

PRIMARY

EROSION

UNUSUAL SEEPAGE CONTROL

TRASHRACK

SECONDARY

PIPE

Primary

ITEM

BASIN

TOWER

ALONG

CLOSURE IF STRUCTURE

Bottom

MOVEMENT DAM

MECHANISM

CLOSURE CONDITION

Ash

TOE

Pond

APPLICABLE

INSPECTED

OUTLET

of I BY

WORKS

OBSERVATIONS

INSPECTION

DATE

ui N 1z CHECK

ACTION

NEEDED NAME

N G W z w A OF

ADDITIONAL

DAM

4 3 2 1 6 COMMENTS 11 789 6 $

13 12 10

16 15 14

1 Flint

LOW

EMB

RUTS CAVE

REFER SLIDE

SLOPE

TO SURFACE

EROSION

SINKHOLE

ABUT

VEGETATION

HORIZONTAL

VEGETATION AREAS

ANDOR

ITEM

Secondary

SLOUGH

ANIMAL

CRACKING

PROTECTION

Bottom

CONTACT

CONDITION

SCARP

PUDDLES

CONDITION

CONDITION ALIGNMENT

Ash

BURROW

Pond

APPLICABLE

INSPECTED

of 2 BY

EMBANKMENT

OBSERVATIONS

INSPECTION

DATE o i I

4 Na CHECK

ACTION a NEEDED NAME

Ili

0a OF Lu z z U v v

ADDITIONAL

DAM

21 17

23 22 20 19 18

27 26 31 25 24

32 30 29 28

35 34 33

COMMENTS

Flint

WET

CAVE

SLIDE

STAFF

WEIRS

REFER

DRAINS

SURVEY

EROSION

SEEPAGE

UNUSUAL

LOCATION

EMBABUT

VEGETATION

FREQUENCY AREAS

GAUGE Secondary

ITEM

SLOUGH

ANIMAL

AND

MOVEMENT CONTACT Bottom

MONUMENTS

CONTROL SCARP

PIEZOMETERSIOBSERV

FLOW

RECORDS

Ash

BURROW

READINGS

Pond

RECORDER WELLS

APPLICABLE

INSPECTED

of 2 BY

EMBANKMENT

OBSERVATIONS

INSPECTION

DATE 0

CHECK

ACTION

NEEDED

pd W NAME O a O Z w J

Z 1 OF WV 4 W Ip

00 z

ADDITIONAL a 00 Z Z Q

DAM

51 0

56 55 54 53 52

57 61 59 58 t

63 62 60

65 67 66 64

69 68

COMMENTS

Flint

WEIR

SLIDE

DEBRIS

REFER

INTAKE

EROSION

STILLING

CHANNEL

UNUSUAL

APPROACH

SIDEWALLS

DISCHARGE

VEGETATION

TRASHRACK

Secondary

ITEM

SLOUGH

i BASIN

FLOOR

AREA

CONTROL

STRUCTURE

MOVEMENT Bottom

CONDITION

SCARP

CONDITION

Ash

Pond

APPLICABLE

INSPECTED

BY r 1

° ••

SPILLWAYS a

I•

e OBSERVATIONS

INSPECTION

DATE

•1 4 CHECK

ACTION

NEEDED Iwo NAME i < 9 O1D j D w OF z CL t in

ADDITIONAL

DAM

72 70 6

81 78 77 76 75 74 73

83 82 80 79

COMMENTS

Flint

Cic

INTAKE

REFER

OUTLET OUTLET

STILLING

PRIMARY

EROSION

SEEPAGE CONTROL

UNUSUAL

TRASHRACK

SECONDARY

PIPE

ITEM

Secondary

BASIN

TOWER

ALONG

CLOSURE

STRUCTURE

MOVEMENT DAM Bottom

MECHANISM

CLOSURE CONDITION

Ash

TOE

Pond

APPLICABLE

INSPECTED

OUTLET

of 1 BY

WORKS

OBSERVATIONS

INSPECTION

DATE

z O

w Q CHECK

ACTION

NEEDED n US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Site Name: Flint Creek Date: 2-15-11 Primary Bottom Ash Unit Name: Pond Operator's Name: SWEPCO

Unit I.D.: Hazard Potential Classification: High Significant Low

Inspector's Name: McLaren / Shepard

Check the appropriate box below. Provide comments when appropriate. If not applicable or not available, record "N/A". Any unusual conditions or construction practices that should be noted in the comments section. For large diked embankments, separate checklists may be used for different embankment areas. If separate forms are used, identify approximate area that the form applies to in comments.

Yes No Yes No 1. Frequency of Company's Dam Inspections? x 18. Sloughing or bulging on slopes? x 2. Pool elevation (operator records)? x 19. Major erosion or slope deterioration? x 3. Decant inlet elevation (operator records)? x 20. Decant Pipes: 4. Open channel spillway elevation (operator records)? x Is water entering inlet, but not exiting outlet? x 5. Lowest dam crest elevation (operator records)? x Is water exiting outlet, but not entering inlet? x 6. If instrumentation is present, are readings recorded x Is water exiting outlet flowing clear? x (operator records)? 21. Seepage (specify location, if seepage carries 7. Is the embankment currently under construction? x fines, and approximate seepage rate below): 8. Foundation preparation (remove vegetation, stumps, x From underdrain? N/A topsoil in area where embankment fill will be placed)? 9. Trees growing on embankment? (If so, indicate x At isolated points on embankment slopes? x largest diameter below) 10. Cracks or scarps on crest? x At natural hillside in the embankment area? x 11. Is there significant settlement along the crest? x Over widespread areas? x 12. Are decant trashracks clear and in place? N/A From downstream foundation area? x 13. Depressions or sinkholes in tailings surface or whirlpool x "Boils" beneath stream or ponded water? x in the pool area? 14. Clogged spillways, groin or diversion ditches? x Around the outside of the decant pipe? x 22. Surface movements in valley bottom or on 15. Are spillway or ditch linings deteriorated? x x hillside? 16. Are outlets of decant or underdrains blocked? x 23. Water against downstream toe? x 24. Were Photos taken during the dam 17. Cracks or scarps on slopes? x x inspection? Major adverse changes in these items could cause instability and should be reported for further evaluation. Adverse conditions noted in these items should normally be described (extent, location, volume, etc.) in the space below and on the back of this sheet.

Issue # Comments

1 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Coal Combustion Waste (CCW) Impoundment Inspection

Impoundment NPDES Permit AR0037842 INSPECTOR John Fazio

Date 3-1-2009 to 2-28-2011 Impoundment Name Primary Bottom Ash Pond

Impoundment Company SWEPCO EPA Region 6

State Agency Arkansas Department of Environmental Quality (Field Office) Address 4170 West 6th St, Suite #5, Fayetteville AR 72704 Name of Impoundment Outfall 101

(Report each impoundment on a separate form under the same Impoundment NPDES Permit number)

New Update Yes No Is impoundment currently under construction? Is water or ccw currently being pumped into the

impoundment? IMPOUNDMENT FUNCTION: Settling Pond

Nearest Downstream Town Watts Name: Distance from the Approximately 32 miles along river impoundment: Location: Latitude 36 Degrees 6 Minutes 28 Seconds N

Longitude 94 Degrees 34 Minutes 17 Seconds W

State Oklahoma County Adair

Yes No Does a state agency regulate this impoundment?

If So Which State Agency?

2 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

HAZARD POTENTIAL (In the event the impoundment should fail, the following would occur):

LESS THAN LOW HAZARD POTENTIAL: Failure or misoperation of the dam results in no probable loss of human life or economic or environmental losses.

LOW HAZARD POTENTIAL: Dams assigned the low hazard potential classification are those where failure or misoperation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner’s property.

SIGNIFICANT HAZARD POTENTIAL: Dams assigned the significant hazard potential classification are those dams where failure or misoperation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or can impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be located in areas with population and significant infrastructure.

HIGH HAZARD POTENTIAL: Dams assigned the high hazard potential classification are those where failure or misoperation will probably cause loss of human life.

DESCRIBE REASONING FOR HAZARD RATING CHOSEN:

If failure occurred it would discharge into much larger cooling pond and would not affect level in cooling pond significantly.

3 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

CONFIGURATION:

Cross-Valley Side-Hill Diked

Incised (form completion optional) Combination Incised/Diked

Embankment Height (ft) 46.5 Embankment Material Native Clay Pool Area (ac) 42.8 Liner N/A Current Freeboard (ft) 10 Liner Permeability N/A

4 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

TYPE OF OUTLET (Mark all that apply)

Open Channel Spillway

Trapezoidal

Triangular

Rectangular

Irregular

depth (ft)

average bottom width (ft)

top width (ft)

Outlet 48” wide X 24” high inside dimensions (Reinforced Concrete)

Material

corrugated metal

welded steel

concrete

plastic (hdpe, pvc, etc.)

other (specify): Yes No Is water flowing through the

outlet?

No Outlet

Other Type of Outlet

(specify):

The Impoundment was Designed By SWEPCO – in house staff

5 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Yes No

Has there ever been a failure at this site?

If So When?

If So Please Describe :

6 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Yes No Has there ever been significant seepages

at this site?

If So When?

If So Please Describe :

7 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Yes No Has there ever been any measures undertaken to monitor/lower Phreatic water table levels based on past seepages or breaches at this site?

If so, which method (e.g., piezometers, gw pumping,...)?

If So Please Describe :

8 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

ADDITIONAL INSPECTION QUESTIONS Concerning the embankment foundation, was the embankment construction built over wet ash, slag, or other unsuitable materials? If there is no information just note that. No, Pond embankment was structurally designed and keyed into native soils that were cleared and grubbed.

Did the dam assessor meet with, or have documentation from, the design Engineer-of-Record concerning the foundation preparation? Documentation was on site

From the site visit or from photographic documentation, was there evidence of prior releases, failures, or patchwork on the dikes? No

9 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Site Name: Flint Creek Date: 2-15-11 Secondary Bottom Unit Name: Ash Pond Operator's Name: SWEPCO

Unit I.D.: Hazard Potential Classification: High Significant Low

Inspector's Name: McLaren / Shepard

Issue # Comments

1 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Coal Combustion Waste (CCW) Impoundment Inspection

Impoundment NPDES Permit AR0037842 INSPECTOR John Fazio

Date 3-1-2009 to 2-28-2011 Impoundment Name Secondary Bottom Ash Pond

Impoundment Company SWEPCO EPA Region 6

State Agency Arkansas Department of Environmental Quality (Field Office) Address 4170 West 6th St, Suite #5, Fayetteville AR 72704 Name of Impoundment Outfall 101

(Report each impoundment on a separate form under the same Impoundment NPDES Permit number)

New Update Yes No Is impoundment currently under construction? Is water or ccw currently being pumped into the

impoundment? IMPOUNDMENT FUNCTION: Settling Pond

Nearest Downstream Town Watts Name: Distance from the Approximately 32 miles along river impoundment: Location: Latitude 36 Degrees 6 Minutes 28 Seconds N

Longitude 94 Degrees 34 Minutes 17 Seconds W

State Oklahoma County Adair

Yes No Does a state agency regulate this impoundment?

If So Which State Agency?

2 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

HAZARD POTENTIAL (In the event the impoundment should fail, the following would occur):

LESS THAN LOW HAZARD POTENTIAL: Failure or misoperation of the dam results in no probable loss of human life or economic or environmental losses.

HIGH HAZARD POTENTIAL: Dams assigned the high hazard potential classification are those where failure or misoperation will probably cause loss of human life.

DESCRIBE REASONING FOR HAZARD RATING CHOSEN:

If failure occurred it would discharge into much larger cooling pond and would not affect level in cooling pond significantly.

3 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

CONFIGURATION:

Cross-Valley Side-Hill Diked

Incised (form completion optional) Combination Incised/Diked

Embankment Height (ft) 35.0 Embankment Material Native Clay Pool Area (ac) 3.7 Liner N/A

4 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Current Freeboard (ft) 12 Liner Permeability N/A

5 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

TYPE OF OUTLET (Mark all that apply)

Open Channel Spillway

Trapezoidal

Triangular

Rectangular

Irregular

2.5 depth (ft)

13.0 average bottom width (ft)

13.0 top width (ft)

Outlet 48” wide X 24” high inside dimensions (Reinforced Concrete)

Material

corrugated metal

welded steel

concrete

plastic (hdpe, pvc, etc.)

other (specify): Yes No Is water flowing through the

outlet?

No Outlet

Other Type of Outlet

(specify):

6 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

The Impoundment was Designed By SWEPCO – in house staff

Yes No

Has there ever been a failure at this site?

If So When?

If So Please Describe :

7 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Yes No Has there ever been significant seepages

at this site?

If So When?

If So Please Describe :

8 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Yes No Has there ever been any measures undertaken to monitor/lower Phreatic water table levels based on past seepages or breaches at this site?

If so, which method (e.g., piezometers, gw pumping,...)?

If So Please Describe :

9 US Environmental Coal Combustion Dam Inspection Checklist Form Protection Agency

Did the dam assessor meet with, or have documentation from, the design Engineer-of-Record concerning the foundation preparation? Documentation was on site

From the site visit or from photographic documentation, was there evidence of prior releases, failures, or patchwork on the dikes? No