Malcolm Pirnie

*— ^. V

MAIXDOLM PIRNIE MALCOLM PIRMIE. INC. ENVIRONMENTAL ENGINEERS. SCIENTISTS I PLANNERS

REMEDIAL INVESTIGATION FINAL REPORT

LONG PRAIRIE GROUND WATER CONTAMINATION SITE

CITY OF LONG PRAIRIE TODD COUNTY, MINNESOTA

MINNESOTA POLLUTION CONTROL AGENCY

OCTOBER, 1987 EPA Region 5 Records Ctr.

228823 0871-02-6018 AWGOUVt PIRNIE MALCOLM PIRNIE. INC. ENVIRONMENTAL ENGINEERS. SCIENTISTS t PLANNERS

October 14, 1987

Mr. Robert J. Einweck Multi-Site Contract Co-ordinator Superfund Unit, Site Response Section Division of Solid and Hazardous Waste Minnesota Pollution Control Agency 520 Lafayette Road North St. Paul, Minnesota 55155 Re: Remedial Investigation (RI) Final Report Long Prairie Groundwater Contamination Site Multi-Site Contract No. 32300-13595 Work Order No. MP-02-B Dear Mr. Einweck:

We are pleased to submit two bound and one unbound copies of the Remedial Investigation Final Report for the Long Prairie Ground- water Contamination Site. This report partially fulfills the requirements of the work order No. MP-02-B. This report incorporates our responses dated August 25, 1987 to Ms. McGovern's letter of July 21, 1987 and those discussed at a meeting of MPCA and Malcolm Pirnie personnel on September 9, 1987. We appreciate the continuing efforts of Messrs. Mark Lahtinen and Dale Thompson in this project. Work on the Feasibility Study is underway. A revised schedule for completing the FS is being submitted under separate cover. If you have any questions, please feel free to call me at 614/888-4953 or Pete Cangialosi at 612/835-2504.

Very^truly yours, / iM PIRNZB, INC.

Manager W15/tdg

c: Mr. John Henningson Mr. Charles Michael Mr. Peter Cangialosi

0871-02-6018

5001 A 3CTH ST SJi'E "70 MINNEAPOLIS MN 55437 612 835-2504 TE^EX 137364 REMEDIAL INVESTIGATION FINAL REPORT

LONG PRAIRIE GROUNDWATER CONTAMINATION SITE LONG PRAIRIE, MINNESOTA

MINNESOTA POLLUTION CONTROL AGENCY

OCTOBER 1987 0871-02-6

MALCOLM PIRNIE, INC. Environmental Engineers, Scientists and Planners 5001 W. 80th Street, Suite 770 Minneapolis, Minnesota 55437

REPT4/tdg LONG PRAIRIE GROUNDWATER CONTAMINATION SITE REMEDIAL INVESTIGATION FINAL REPORT TABLE OF CONTENTS

SECTION TITLE PAGE EXECUTIVE SUMMARY 1 to 22 1.0 INTRODUCTION 1-1 1.1 General 1-1 1.2 Site Location 1-1 1.3 Historical Background 1-1 1.4 Remedial Investigation 1-3 1.4.1 Objective and Procedure 1-3 1.4.2 New Well Installations 1-4 1.4.3 Rehabilitation of Existing Monitoring Wells 1-6 1.4.4 Waste Characterization 1-6 1.4.5 Well Measurements 1-8 1.4.6 Pump Test 1-9 1.4.7 Soil Monitoring 1-9 1.4.8 Analytical Methods 1-10 1.4.9 Identification of Method of Release 1-10 1.5 Overview of This RI Investigation Report 1-11 2.0 SITE FEATURES 2-1 2.1 Data Sources 2-1 2.2 Regional and Local Physiography 2-1 2.3 Regional Geology 2-2 2.3.1 Unconsolidated Deposits 2-2 2.3.2 Bedrock 2-2 2.4 Local Geology 2-2 2.5 Regional Hydrology and Hydrogeology . . . 2-3 2.5.1 Surface Water Hydrology 2-3 2.5.2 Hydrogeology 2-4 3.0 HAZARDOUS SUBSTANCE INVESTIGATIONS 3-1 3.1 Hazardous Substances, Pollutants, or Contaminants 3-1 3.1.1 Types and Locations 3-1 3.1.2 Physical States and Composition . 3-5 3.1.3 Quantities 3-6 3.2 Mediums Affected 3-7 3.2.1 Soil 3-7 3.2.2 Groundwater 3-8 3.2.3 Surface Water 3-9 3.3.4 Air 3-9 3.3 Pathways of Migration/Sources of Release 3-9 3.4 Waste Component Characteristics 3-10 3.4.1 Environmental Transformation . . . 3-10

REPT4/tdg LONG PRAIRIE GROUNDWATER CONTAMINATION SITE REMEDIAL INVESTIGATION FINAL REPORT TABLE OF CONTENTS (Continued)

SECTION TITLE PAGE 3.4.2 Pharmakokinetics, Metabolism, and Toxicity 3-11 4.0 GEOLOGIC AND HYDROGEOLOGIC INVESTIGATION . . . 4-1 4.1 Site Specific Geology 4-1 4.1.1 Test Borings, Logs, and Cross-Sections 4-2 4.2 Site Specific Hydrogeology 4-6 4.2.1 Groundwater Table Elevations . . . 4-6 4.2.2 Hydrogeologic Evaluation 4-6 4.2.3 Aquifer Tests 4-8 4.3 Groundwater Quality 4-11 4.3.1 Groundwatjer Monitoring Programs 4-11 4.3.2 Groundwater Analyses 4-23 4.3.3 Groundwater Contamination Assessment and Migration .... 4-47 5.0 SURFACE WATER AND SEDIMENT INVESTIGATION ... 5-1 6.0 AIR INVESTIGATION 6-1 7.0 BIOTA INVESTIGATION 7-1 8.0 BENCH AND PILOT SCALE STUDIES 8-1 9.0 PUBLIC HEALTH AND ENVIRONMENTAL CONCERNS . . . 9-1 9.1 Introduction 9-1 9.2 Summary of Analytical Results 9-1 9.3 Potential Receptors 9-3 9.4 Health Concerns 9-3 10.0 POSSIBLE ALTERNATIVE RESPONSE ACTIONS .... 10-1 10.1 Introduction 10-1 10.2 Alternative Response Actions 10-1 11.0 BIBLIOGRAPHY 11-1

APPENDICES: Appendix A - Boring Logs Appendix B - Monitoring Well Construction Data Appendix C - Pump Test Drawdown and Recovery Data Appendix D - Pumping Test Plots

REPT4/tdg LONG PRAIRIE GROUNDWATER CONTAMINATION SITE REMEDIAL INVESTIGATION FINAL REPORT TABLE OF CONTENTS (Continued)

LIST OF TABLES TABLE NUMBERS TITLE PAGE 1-1 Proposed Wells/Actually Installed Wells 1-5 1-2 Wells Sampled During Round 1 1-7 3-1 Physical Characteristics of Known Contaminants 3-2 4-1 Long Prairie Well Data 4-4 4-2 Ground Water Altitudes 4-7 4-3 Aquifer Test Results 4-10 4-4 Chlorinated Ethylene Concentrations/ Municipal Wells 4-12 4-5 Chlorinated Ethylene Concentration/ Private Wells 4-13 4-6 Domestic Well Owners in Long Prairie 4-15 4-7 Monitoring Well Construction Details . 4-21 4-8 Monitoring Well Analyses 4-22 4-9 MDH Method 465B Analytes 4-24 4-10 Round 1 Analytical Results - Method 601 4-26 4-11 Aquifer Test Analyses - Method 601 . . 4-39 9-1 Comparison of Contaminant Concentrations in Groundwater to Applicable or Relevant and Appropriate Requirements 9-5 9-2 Comparison of Maximum Contaminent Concentrations in Groundwater to Toxicity Guidelines 9-7 10-1 Potentially Applicable Remedial Technologies 10-2 LIST OF FIGURES

FIGURE FOLLOWING NUMBER TITLE PAGE 1-1 Location of Long Prairie 1~1 1-2 General Site Area 1-1 1-3 Back Lot Area Behind the Dry Cleaner 1"10 2-1 Surficial Geology of the Long Prairie Region ^-l 2-2 Geologic Block Diagram 2-3

REPT4/tdg LONG PRAIRIE GROUNDWATER CONTAMINATION SITE REMEDIAL INVESTIGATION FINAL REPORT TABLE OF CONTENTS (Continued)

LIST OF FIGURES (Continued)

FIGURE FOLLOWING NUMBER TITLE PAGE 3-1 Concentrations of PCE in Private and Municipal Wells. October- November, 1983 3-3 3-2 Concentrations of PCE in Private and Municipal Wells. January- February, 1984 3-3 3-3 Concentrations of PCE in Private and Municipal Wells. October 1986 - February 1987 3-3 4-1 Well Locations and Lines of Sections 4-2 4-2 Geologic Cross-Section A-AI 4-3 4-3 Geologic Cross-Section B-B. 4-3 4-4 Geologic Cross-Section C-C 4-3 4-5 Groundwater Altitude Contour Map, November 27, 1986 4-7 4-6 Groundwater Altitude Contour Map December 22, 1986 4-7 4-7 Groundwater Altitude Contour Map January 12, 1987 4-7 4-8 Well Location Map 4-22 4-9 New and Existing Monitor Well Locations 4-38 4-10 PCE Solute Transport Simulation, Initial Calibration 4-51 4-11 PCE Solute Transport Simulation, No Action Simulation - 5 years .... 4-52 4-12 PCE Solute Transport Simulation, No Action Simulation - 10 Years . . . 4-52 4-13 PCE Solute Transport Simulation, Municipal Well 4 Pumping - 5 Years. 4-53 4-14 PCE Solute Transport Simulation, Municipal Well 4 Pumping - 10 Years 4-53 4-15 PCE Solute Transport Simulation, 4 Recovery Wells - 1 Year 4-54 4-16 PCE Solute Transport Simulation, 4 Recovery Wells - 3 Years 4-54 4-17 PCE Solute Transport Simulation, 4 Recovery Wells - 5 Years 4-54 10-1 Appropriate General Response Actions 10-1

REPT4/tdg REMEDIAL INVESTIGATION (RI) FINAL REPORT LONG PRAIRIE GROUNDWATER CONTAMINATION SITE

EXECUTIVE SUMMARY

1.0 INTRODUCTION 1.1 Site Location The city of Long Prairie, Minnesota, with a population of approximately 2,500, is situated in the Long Prairie River Valley in central Minnesota and is the county seat of Todd County. Figure 1-1 shows the location of Long Prairie and Todd County in Minnesota. Municipal water supply is not available to all City residents; some of them obtain their water supply from their own private wells. The Long Prairie Groundwater Contamination Site consti- tutes an area of contaminated groundwater in an aquifer located below the northeast quadrant of Long Prairie. The general site area is shown in Figure 1-2.

1.2 Historical Background In late 1983, samples from Municipal Wells 1 through 5 serving the City of Long Prairie indicated contamination of Municipal Wells 4 and 5 by chlorinated ethylene compounds. Analyses showed the presence of 1,1,2,2-tetrachloroethylene, also called Perchloroethylene or PCE, at 26 and 270 ug/1 in wells 4 and 5, respectively. The wells also indicated lower levels of 1,1,2 trichloroethylene (at 1 and 11 ug/1, respectively) and cis-l,2-dichloroethylene (at 0.8 and 16 ug/1, respectively). Municipal Wells 4 and 5 were shut down. The MPCA initiated a sampling program of over 90 private residential wells in the northeastern section of Long Prairie. Analytical results showed contamination by PCE in approximately half of the private wells sampled. The Minnesota Depart- ment of Health issued a drinking water advisory on November 1, 1983 for residents with private drinking water wells in a 15 square block area of northeastern Long Prairie.

tREPT4/tdg -1- In November, 1983, MPCA's investigation concluded that the problem originated from a long-existing dry cleaning establishment at 243 Central Avenue adjacent to the City Hall in the center of Long Prairie. In September, 1984 the United States Environmental Protection Agency (EPA) and the MPCA executed a cooperative agreement for implementing a remedial investigation and feasibility study (RI/FS) at the site. The site was proposed for inclusion on the National Priorities List in October, 1984. On August 8, 1985, MPCA asked Malcolm Pirnie, Inc. to conduct the RI/FS for the site. A work plan to conduct these studies was prepared and submitted to MPCA on July 24, 1986. MPCA approved the work plan and authorized Malcolm Pirnie to commence RI activities on September 23, 1986. This report presents the results of these activities.

1.3 Remedial Investigation Up to eleven new monitoring wells were proposed in the Work Plan to further define the vertical and horizontal extent of contamination. Clusters of wells with varying depths were proposed to determine the vertical profile of groundwater contamination by a contaminant, such as PCE, which is denser than water and tends to "sink" through the aquifer. As shown in Table 1-1, some of the wells proposed in the work plan were not installed. The work plan proposed three rounds of groundwater sampling and analysis. In alL rounds, the sampling techniques and chain of custody procedures were in accordance with the Quality Assurance Project Plan (QAPP). The first round of groundwater sampling was performed on all existing monitoring wells, Municipal Well Nos. 3, 4, 5, and 6, and nine selected private wells in the affected area as listed in Table 1-2. The samples were analyzed for volatile constituents using EPA Method 601.

REPT4/tdg -2- The second round of sampling included the eight new monitoring wells and the existing monitoring wells BAL-2B, 6C and municipal well 6. Monitoring well 6C was sampled in the second round in place of an upgradient well which was not installed. During the second round of sampling, groundwater samples for full HSL analysis were obtained from MW-10 and MW-6C. Based on previously available data, non-volatile contaminants were believed to be absent in these wells? the HSL analyses confirmed it. These two monitoring wells were selected for HSL analysis because the highest concentration of contaminants were suspected at these locations based on analytical information from the first round of sampling and information. The third round of sampling was conducted on the 16 previously existing monitoring wells originally sampled in the first round, and the eight new monitoring wells sampled in the second round. Analytical data from the third round of sampling was used to confirm the presence and levels of contaminants detected in the earlier rounds. Water level measurements of all wells were taken a total of five times during the RI. These measurements were taken to develop groundwater contour maps and to show fluctuations of seasonal water levels. A constant rate pumping test on municipal well no. 4 was conducted to obtain data which would help determine the following: o Aquifer transmissivity (the rate at which water will flow through a one-foot wide vertical strip of the aquifer under a gradient of 1.0), and o Storage coefficient (the volume of water released from storage from a one cubic foot portion of the aquifer). Six groundwater samples were obtained at five intervals during the pump test for volatile organics analyses.

REPT4/tdg -3- Test borings were conducted at all cluster and single well locations. However, in order to increase the rate of drilling, the number of split-spoon samples were reduced in areas of homogenous soil conditions and in areas where the presence of high levels of contaminants was considered unlikely. In addition to the soil borings completed at the cluster and single well locations, two soil borings were conducted in the back lot along the south wall of the dry cleaning building as outlined in the work plan (Figure 1-3). The purpose of these soil borings was to help determine whether this building was the source of the contamination. A third test boring labeled as "TB-C" was conducted approximately 50 feet directly south of TB-A and 25 feet east of MW-10. A soil sample from this boring was analyzed for the volatile fraction of the HSL. Both boring locations are shown on Figure 1-3.

1.4 Analytical Methods Ground-water samples were analyzed using USEPA Method 601 for volatile organic chemicals by PACE Laboratories as outlined in the QAPP. Certain groundwater and soil samples were analyzed using Contract Laboratory Program (CLP) procedures for HSL parameters also as described in the QAPP.

2.0 SITE FEATURES 2.1 Regional Geology The City of Long Prairie is located on a long, narrow, glacial outwash plain commonly referred to as the Long Prairie Sand Plain. The sands and gravels of the Long Prairie Sand Plain were most likely deposited by outwash streams during the retreat of the Rainy/Superior glacial lobes. West of the Long Prairie Sand Plain lies the Wadena Till Plain which was deposited by the Wisconsin glacial advance. The till plain deposits are composed of an unsorted mixture of

REPT4/tdg -4- sand with varying amounts of clay, silt, gravel and boulders and are commonly referred to as the "gray drift" due to their characteristic gray color. The glacial deposits are reportedly underlain by Precam- brian igneous and metamorphic bedrock (Kanivetsky, 1978). The rocks lack primary porosity and may not function as aquifers. Some successful wells are reported in areas where the rocks have been faulted or fractured, but even under these conditions groundwater occurrence is highly uncertain.

2.2 Local Geology A geologic block diagram was developed based on data from 17 monitoring wells and two test borings. As depicted in Figure 2-2 the uppermost geologic unit is a silty sand with some coarser sand and gravel. This is the glacial outwash deposit that is the most prolific aquifer in the area. These sediments range from 7 feet thick at the location of Test Boring No. 8, to 56 feet thick at Municipal Well No. 6 and up to 66 feet thick in the vicinity of Monitoring Well BAL-2. This silty sand unit contains scattered, discontinuous clay lenses such as those represented at well location No. 4 and wells BAL-1 and BAL-2. Underlying the glacial outwash sediments is glacial till composed of sandy clay with varying concentrations of gravel. The till appears to extend to a depth of at least 200 ft below ground level (bgl) and appears to be continuous beneath the site. The glacial till is reportedly underlain by Precambian igneous and metamorphic rocks (Kanivetsky, 1978). The bedrock is not considered an aquifer.

2.3 Regional Hydrology and Hydrogeology The Long Prairie River flows into the City from the west- northwest and turns approximately 110 degrees to the north,

REPT4/tdg -5- flowing almost due north when it leaves the city. The discharge records for the river approximately 12 miles upstream from Long Prairie at the gaging station near Osakis show the average annual discharge to be 95 cubic feet per second (cfs). The Long Prairie River is part of the Crow Wing River drainage basin which is in turn tributary to the Mississippi River. The poor permeability of the upland tills of the St. Croix Moraine and Wadena Till Plain retards percolation of precipitation into the underlying sediments. The low permeability of these deposits results in many lakes at an elevated height on uplands. These deposits lie on either side of the Long Prairie Sand Plain, a highly permeable deposit which is the most productive aquifer in the area. Groundwater flow at the site has been evaluated using data from existing monitoring wells. A groundwater contour map, which was developed based on measured ground-water elevations, shows that ground-water flow is to the north- northeast, discharging into the Long Prairie River.

3.0 HAZARDOUS SUBSTANCE INVESTIGATIONS 3.1 Contaminant Types and Source 1,1,2,2-Tetrachloroethylene or PCE is the predominant contaminant in terms of concentration present at the Long Prairie site. The wells found to be contaminated are in the northeastern quadrant of Long Prairie north of First Avenue SE and east of the Long Prairie River. Isoplots showing lines of equal concentration of PCE show an elongated plume of contaminated groundwater extending along a southeast/northeast axis from the center of the city to approximately Fourth Avenue NE near municipal well No. 4 at Todd Street. The plume's length is approximately 2,100 feet and its width is approximately 1,000 feet. Contamination appears to be throughout the saturated depth of the sand aquifer. This depth ranges from the ground surface between Central and First Avenues SE where the aquifer thins out, to approximately 55 feet in depth near municipal well No. 4.

REPT4/tdg -6- The isoplots indicate that the source of contamination apparently originates from the center of the city near the City Hall located on Central Avenue east of Second Street NE. Investigations in October, 1983 by MPCA of PND Cleaners at 243 Central Avenue revealed traces of visible spillage/leakage from dry cleaning machinery over the floor boards and onto the soil in the basement. It appeared that the release of PCE occurred at this site. During the RI, three soil borings were conducted to the bottom of the overlying sand layer in the asphalt-paved back lot behind the dry cleaning operation shown in Figure 1-3. At the extreme rear of the lot adjacent to the Armory, a badly deteriorated, no longer used, brick kiln or oven was observed. Below and slightly in front (to the east) of the kiln is a steel drum buried in the ground so that approximately 2 inches of the top rim is seen above the ground surface. A gray clay-like material resembling wet ash was observed in the drum. High VOC readings were recorded for split-spoon soil samples from all boring locations in the back lot and at the buried drum during the course of the remedial investigation. Analytical results of soil samples from borings TB-A and TB-C indicated that PCE was not present in the soil sample from TB-A; although it was present at a concentration of 11 ug/kg in the soil sample from TB-C. A sample of the material in the buried drum showed PCE at a concentration of 1,500 mg/kg. Groundwater samples were obtained twice from MW-10 located 22 feet downgradient (to the north) of the buried drum. Analyses showed PCE at concentrations of 13,000 ug/1 and 22,000 ug/1 in the two samples. Based on this investigation, it appears that the exact source of the contaminants is the buried drum in the back lot near the Armory. With the high concentrations of PCE in groundwater and soils upgradient of the dry cleaning building,

REPT4/tdg -7- it would appear that the actual operations within the building probably were not a major source of contaminants. Instead, it is more probable that dumping or spillage in the rear of the building contributed significantly to groundwater and soil contamination.

3.2 Mediums Affected 3.2.1 Soil The area of major soil contamination is in the back lot between the dry cleaner and the Armory. The volume of contaminated soil cannot be fully determined at this time. 3.2.2 Groundwater A plume of contaminated groundwater extends from the lot between the dry cleaner to approximately Fourth Avenue NE near Municipal Well 4. 3.2.3 Surface Water No surface water samples were taken during the remedial investigation. However, analyses of surface water samples from the study area collected in 1984 by MPCA personnel did not indicate contamination by volatile organic compounds. In addition, based on information generated during RI activities, it appears unlikely that contaminants will migrate to the Long Prairie River or the wetlands for a period of at least 10 years under present pumping conditions. 3.2.4 Air No known ambient air contamination exists in Long Prairie as a result of groundwater contamination. Ambient air monitoring was conducted during subsurface drilling activities. Positive readings of organic vapors as recorded by a portable photoionization detector (HNu) were detected at only two of the boring locations. These were both located in a back lot behind the Long Prairie Cleaners building near the suspected source of contamination.

REPT4/tdg -8- 3.3 Pathways of Migration/Sources of Release As stated before, it appears the major source of release of contaminants was through dumping or spillage of PCE contaminated wastes on to the soils in the back lot of the dry cleaner. It is probable that PCE wastes were either discharged to the soil through the partially buried drum or were simply spilled on the ground prior to its being paved. Spills or leaks from within the dry cleaning building may also account for some of the groundwater contamination noted downgradient. However, because of the large concentrations found in Monitoring Well 10 located upgradient of the building and just 22 feet downgradient of the drum, it appears likely that the area around the drum is the most likely source of the contamination.

3.4 Waste Component Characteristics Degradative transformation of PCE through TCE and through one or more dichlorethylene intermediates such as cis-1,2- dichloroethylene and 1,1-dichloroethylene, to vinyl chloride has been suggested (Science Applications International Corpo- ration, 1985). In soils, especially in soils of low organic content, the chlorinated ethylenes will leak into groundwater. PCE and TCE adsorb to soils with high levels of organics; sorption is probably an insignificant fate process for cis-1,2-dichloroethylene and vinyl chloride. It is unclear if PCE and TCE bound to organic material can be degraded by microorganisms or if they must be desorbed to be degraded. The most important transport and fate process for the chlorinated ethylenes in the upper layer of soil and surface water is volatilization into the atmosphere where they can react with hydroxyl (OH~) radicals to produce hydrochloric acid, carbon monoxide, carbon dioxide and carboxylic acid.

REPT4/tdg -9- The chlorinated ethylenes can be bio-accumulated to some degree and there is some evidence that they can be metabolized by higher organisms. Bioaccumulation and biodegradation do not appear to be important environmental fate processes for vinyl chloride. Tetrachloroethylene or PCE (CCl^CCl^) - PCE is a moder- ately volatile chlorinated hydrocarbon which has important applications in the dry cleaning of fabrics and in the de- greasing of fabricated metal parts. It is nearly insoluble in water but is highly lipophilic. The effects of PCE on the central nervous system are the most noticeable. Effects on the liver and kidneys have also been noted. The USEPA classifies PCE as a Group B2 probable human carcinogen via both oral and inhalation routes of exposure. The classification is based on the results of a bioassay conducted by the National Cancer Institute. In terms of relative potency, PCE ranks in the lowest quartile among 55 suspected or known carcinogens evaluated by the USEPA Carcinogen Assessment Group.

Trichloroethylene or TCE (CHC1CC12) - The USEPA classifies TCE as a Group B2 probable human carcinogen (sufficient animal evidence of carcinogencity and inadequate human evidence) via both oral and inhalation routes of exposure. Based on relative potency, TCE ranks in the lowest quartile among the 55 suspect or known carcinogens evaluated by the USEPA Carcinogen Assessment Group. cis-l,2-Dichloroethylene (C1CHCHC1) - Long-term studies on the carcinogenic potential of cis-1,2-dichloroethylene have not been carried out and the compound is in Group D not classified in the USEPA weight of evidence categories for potential carcinogens. Vinyl Chloride (CH^CHCl) - Vinyl chloride has been known to have carcinogenic effects in humans and animals from both oral and inhalation routes. It is a Group A human carcinogen (sufficient evidence from epidemiological studies) in the

REPT4/tdg -10- USEPA weight-of evidence categories for potential human carcinogens. In humans, exposure to vinyl chloride is associated with angiosarcoma of the liver.

4.0 GEOLOGIC AND HYDROGEOLOGIC INVESTIGATIONS 4.1 Site Specific Geology Numerous borings in the work area have shown that the outwash sands and gravels lie as an arcuate wedge curving from a north-south orientation on the west wall of the St. Croix Moraine to a east-west orientation on the north side of the till spur. The outwash sands and gravels thicken both to the north from the town center and to the west from the till hills lying to the east. North of the town center the outwash sands and gravels quickly thicken as the underlying till drops off steeply. The till goes from a near surface or possible surface exposure at the Todd County Court House to a depth of 50 to 60 feet within one half mile. An impermeable layer extends west from the area of municipal well 6 at a depth of approximately 40 feet. The density of this material seems to indicate that it is a till deposit versus a lacustrine (lake) clay deposit. This deposit pinches out to the west near the location of municipal wells 4 and 5 and to the south between monitoring wells 4 and 6. A total of ten test borings were drilled by hollow stem auger. The test boring logs were used to generate cross sections representative of the area geology. The cross sections are given in Figures 4-2, 4-3, and 4-4. Borings drilled at seven of the locations served the additional purpose of aiding in proper monitoring well installation. Information regarding previously existing and new wells is given in Table 4-1. All wells were cemented at the surface, installed with locking caps and surrounded with guard posts. Monitoring well construction data for each well appear in Appendix B.

REPT4/tdg -11- 4.2 Site Specific Hydroqeology The section of the Long Prairie River located within the City of Long Prairie is underlain by highly permeable sands and gravel which form the aquifer that supplies groundwater to the city. The aquifer's extent is limited by low permeability glacial tills which form the uplands to the river valley. The aquifer is predominantly under water table conditions with scattered clay lenses which act as local confining units. As part of the remedial investigation, a 72 hour pumping test was conducted at municipal well no. 4 from March 12 - March 16, 1987. Municipal well no. 5 and monitoring well nos. 4A, 4B, 4C, 13C, 14B, and 14C were used as observation wells. Pumping test data analysis is based on the Theis non- equilibrium formula and modification thereof. The Long Prairie pumping test data was analyzed by the Jacob Straight Line Approximation and Boulton's Method for aquifer tests under water-table conditions. Results are tabulated in Table 4-3. The values of transmissivity obtained show an excellent aquifer capable of transmitting large amounts of water. The high values of transmissivity are supported by the near instantaneous response recorded in the monitoring wells equipped with continuous recorders. The wetlands located west of the pumping well serve as a positive boundary, supplying water to the municipal well and preventing accurate analysis of true transmissivity late in the pumping test. The calculated storage coefficient represents an acceptable value for water table aquifers.

4.3 Ground Water Quality The analytical results of municipal well sampling are given in Table 4-11. Municipal wells 1 and 2 were not sampled during this remedial investigation since previous analyses by MPCA did not show contamination and they are not hydrogeologically connected to the area of known groundwater contami-

REPT4/tdg -12- nation. Municipal well 1 is screened from a depth of 27 to 42 feet below ground surface while Municipal well 2 is screened from 100 to 115 feet. Analytical results of the sample obtained from Municipal well 3 was considered inconclusive due to contamination of an associated blank sample. However, results generated by the Minnesota Department of Health did not indicate contamination as shown on Table 4-4. Analyses of municipal well 4 which has not been used as a source for potable water since October, 1984, indicate contamination by three contaminants. These include cis-l,2-dichloroethylene, 1,1,2-trichloroethylene, and 1,1,2,2-tetrachloroethylene. In municipal well 4, as in all of the wells sampled during the remedial investigation, the contaminant found at the highest levels is PCE. This analyte was detected at 220 ug/1 in Round 1 and at concentrations increasing from 84 to 200 ug/1 through the hydrogeologic investigation. The other two analytes detected were present in concentrations less than 10 ug/1. When these results are compared to those obtained by MDH in 1983-84, the RI results show values which are approximately double those obtained by the MDH. These continue a general increasing trend observed since the MDH results were obtained. This condition is reversed, though, for the analytical results from monitoring well 5. The same three major contaminants found in municipal well 4 are also found in municipal well 5, although at lower concentrations. MDH analytical results for 1983-84 are significantly higher for all three, especially for PCE. MDH results generally decreased with time from 280 to 100 ug/1. The lower value obtained during the RI, 24 ug/1, continued the downward trend. Analytical results from each of the three rounds from municipal well 6 do not indicate contamination. Analytical results from other monitoring wells are discussed below.

REPT4/tdg -13- MW-1A; - Very low levels (less than 1.5 ug/1 each) of the three main contaminants: cis-l,2-dichloroethylene, 1,1,2- trichloroethylene, and 1,1,2,2-tetrachloroethylene. MW-1B; - No contamination. MW-2A - While 30 ug/1 of PCE was detected in the first round analysis, it was not confirmed in the second analysis. The RI analytical results indicate considerably less contamination than those of MDH obtained in 1984 when a concentration of 160 ug/1 of PCE was detected. MW-2B; - Analytical results confirm high levels of PCE (160 and 290 ug/1). Significant levels of cis-1,2-dichloroethylene and 1,1,2-trichloroethylene were not confirmed in the RI. MW-2C; - Analytical results indicate high levels of PCE (210 ug/1) although much lower levels of the other two contaminants (less than 5 ug/1). MW-3A; - Analytical results did not confirm the presence of contamination. MW-3B; - Analytical results did not indicate contamination. MW-4A; - Analytical results indicate very low levels of PCE contamination (2.0-5.8 ug/1) and lower levels of the other contaminants. MW-4B; - High levels of PCE (80-150 ug/1) were detected in samples obtained during the RI but slightly lower than those obtained by MDH. MW-4C; - Analytical results confirm PCE at high levels (75-110 ug/1). Concentrations for cis-1,2-dichloroethylene and 1,1,2-trichloroethylene are similar to those detected by MDH (5.6-8.2 ug/1). MW-5A; - Analytical results indicate a low level of PCE (1.9 ug/1). Cis-1,2-dichloroethylene was also present at a low level (2.0 ug/1) similar to that detected by MDH (2.7 ug/1). 1,1,2-Trichloroethylene is not reliably found in the RI results although it was detected at 2.6 ug/1 by MDH.

REPT4/tdg -14- MW-5B; - Analytical results indicate low levels of PCE contamination (2.9-7.6 ug/1) and lower levels of the other contaminants. MW-6A; - An analysis of the first sample from this well obtained during the RI indicated low levels of 17 compounds. However only cis-1,2-dichloroethylene, 1,1,2-trichloroethylene, and PCE were detected in a second analysis. MW-6B; - Analytical results indicate PCE contamination at 53-65 ug/1. Levels of the other two contaminants are less than 4 ug/1. MW-6C; - Levels of all three contaminants are higher in MW-6C than most of the other monitoring wells. PCE concentrations ranged from 49-340 ug/1; cis-1,2-dichloroethylene was detected at 8.7 ug/1. 1,1,2-Trichloroethylene was detected at 16-38 ug/1 during the RI and at 17 ug/1 by MDH. Full hazardous substance list (HSL) analyses were conducted on the Round 2 sample from MW-6C. No contaminants in fractions other than the volatile fraction were detected. MW-7A; - Indicated no contamination. MW-9A; - 1,1,2-Trichloroethylene was detected at a low level of 1.0 ug/1. The other contaminants were not confirmed present during the RI nor by MDH. MW-10; - The highest levels of contamination were detected in MW-10. PCE was confirmed present at 13000-22000 ug/1, cis-1,2-dichloroethylene was found present at 52-68 ug/1, and 1,1,2-trichloroethylene was found at 300-660 ug/1. MW-11; - Contamination was not confirmed in this well. MW-13C; - Contamination was not confirmed in this well. MW-14B; - Contamination at appreciable levels was not confirmed. MW-14C; - Contamination was not confirmed in this well. BAL-2B; - Did not confirm contamination. BAL-2C; - Very low levels of 1,2-dichloroethylene (0.9-1.7 ug/1).

REPT4/tdg -15- Samples from nine residential wells in the northeastern quadrant of Long Prairie were obtained during Round 1 of the RI. In general, these residential wells did not show contamination. However, the Werlinger well showed PCE present at 2.1 ug/1. The Harren well confirmed cis-1,2-dichloroethylene at a low concentration of 0.5 ug/1.

4.4 Groundwater Contamination Assessment and Migration The movement of 1,1,2,2-Tetrachloroethylene (PCE) through the Long Prairie Sand Plain aquifer was evaluated using the U.S.G.S. computer model of Two - Dimensional Solute Transport and Dispersion in Ground Water- which was compiled by Konikow and Bredehoeft in 1978. Three general simulations were run in order to evaluate the PCE plume movement under different conditions. 1. No Action Simulation This simulation was run to evaluate plume movement if nothing was done to remediate the contamination and wells No. 4 and 5 remained shut down but municipal well #6 continued to pump at its present rate. Figure 4-11 represents the plume movement after a period of 5 years and Figure 4-12 represents the plume movement after a period of 10 years. The model indicates that the plume will not drastically change position with time but will move slowly in a northerly direction along with the natural groundwater flow. The portion of the plume with the highest initial concentration, near the Long Prairie Cleaners, will slowly disperse and decrease in concentration while moving northward at a rate of approximately 0.435 feet per day. The portion of the plume with the lower initial concentration, near municipal well #4, will also disperse and decrease in concentration but -at a much slower rate. Overall plume movement in the no action simulation is to the north rather than to the north east as reflected in the initial plume orientation. The model indicates that municipal well No. 6 does not appear to be in danger of contamination

REPT4/tdg from the known PCE plume. However, the model indicates that the contaminant plume will remain in the same general area for some time to come. 2. Municipal Well No. 4 Pumping This simulation was run to evaluate plume movement as if municipal well No. 4 was restarted and allowed to pump at its full capacity while municipal well No. 6 also continued to pump. Figure 4-13 represents plume movement after 5 years and Figure 4-14 represents the movement after a 10 year period. The model indicates that the plume will disperse somewhat transversely but will continue to be drawn toward well 14. The portion of the plume with the highest initial concentration will continue to be drawn in that direction but will lengthen in a north-easterly direction due to the effect of municipal well No. 4 on the longitudinal dispersivity. The portion of the plume with the lower initial PCE concentration will essentially be removed by the pumping at well No. 4, but the remainder of the plume will slowly migrate toward the well under the influence of pumping and the PCE concentration in the area of municipal well No. 4 will gradually increase as the main body of the plume approaches the well No. 4. Overall plume movement in this simulation with well No. 4 pumping is indicated to be toward the northeast. The model indicates that municipal well No. 4 should effectively divert the plume from moving past its location and that municipal well No. 6 does not appear to be in danger of contamination from the known PCE plume under these conditions. However, the model also indicated that municipal well No. 4 by itself will not effectively remove the mass of contaminated groundwater in any reasonable time frame. 3. Recovery Wells This simulation was run to evaluate the effect of a series of recovery wells on plume movement and potential remediation. The actual placement, depth and pumping rate of any series of recovery wells installed at this site will need

REPT4/tdg -17- to be designed very carefully due to the varying aquifer transmissivity as the sand wedge thins through the area of concern. Several combinations of well placement and pumping rates were simulated but Figures 4-15, 4-16, 4-17 show one potential combination that appears to effectively remove the contaminant plume without causing excessive drawdown in the aquifer. In this simulation, one recovery well is placed at the suspected source, municipal well No. 4 is pumping at a reduced rate and three additional recovery wells are located along the plume and are operating at varying rates. The hypothetical pumping rates vary from 90 gallons per minute at municipal well No. 4, down to 18 gallons per minute at recovery well No. 1. The model indicates that after one year under these conditions the shape and size of the plume do not change drastically but a significant concentration of PCE appears to have been removed although concentrations of just over 200 ug/1 will remain as shown on Figure 4-15. After three years of pumping under these conditions the plume appears to be reduced significantly in size and concentrations have decreased to just over 100 ug/1 as shown in Figure 4-16. The model further indicates that after 5 years of pumping under these conditions almost all of the plume appears to have been removed and that only a small area remains with PCE concentrations at about 50 ug/1 as shown on Figure 4-17. Overall plume movement in this simulation indicates that a system of recovery wells appears to effectively remove the PCE plume within a reasonable amount of time. Model predic- N *' tions of the time necessary for remediation are minimal compared to actual operating systems but are consistent with respect to high initial efficiency and long term decreasing recovery rates. It must be noted that this simulation does not represent an actual design of a recovery system but illustrates conceptually the effectiveness of such a system.

REPT4/tdg -18- The scale at which these simulations were run is not sufficient to allow for consideration of small local variations in groundwater flow, gradient and changes in transmissivity. A more detailed, large scale modeling effort would be needed for actual system design along with field verification.

5.0 SURFACE WATER AND SEDIMENT INVESTIGATION Possible contamination of water and sediment were not investigated during this RI. Based on a review of background information, it was not warranted to undertake these tasks due to the nature of the contamination problem in Long Prairie.

6.0 AIR INVESTIGATION The air investigation conducted during this RI was limited to real-time ambient monitoring during drilling activities. The monitoring was performed as an ongoing health and safety requirement and to assist in the selection of subsurface soil samples. Air monitoring using a photoionization instrument was conducted in the immediate work area. Positive HNu readings were recorded while drilling commenced at monitoring well 10 and at test boring A. The readings abated following installation of the well and filling in of the test boring.

7.0 BIOTA INVESTIGATION Possible contamination of biota was not investigated during the RI. Based on a review of background information, it was not warranted to undertake this task due to the nature of the contamination problem in Long Prairie.

8.0 BENCH AND PILOT SCALE STUDIES Bench and pilot scale studies were not undertaken as part of the RI. These studies may be recommended as part of the feasibility study.

REPT4/tdg -19- 9.0 PUBLIC HEALTH AND ENVIRONMENTAL CONCERNS 9.1 Summary of Analytical Results Analyses of groundwater samples collected from Long Prairie Municipal Well Nos. 4 and 5 in August and October, 1983 indicted that these wells were contaminated by tetrachloroethylene (PCE), cis-1,2-dichloroethylene and trichloroethylene (TCE). The two wells were shut down in October, 1983.

9.2 Health Concerns The human exposure pathway of concern in Long Prairie is via groundwater, whether it is supplied municipally or obtained from private supply wells. Exposure may occur via drinking or non-drinking water use of the groundwater. Recently, research has suggested that ingestion of contaminants in drinking water may not constitute the sole or even primary route of exposure (Andleman et al., 1986; Symms 1986; Brown et al., 1984). The release of volatile organic contaminants from bath or shower water can result in inhalation exposures that may be significant when compared to direct ingestion of these contaminants (Andleman et al., 1986; Symms, 1986}. Similarly, skin absorption of contaminants in water during washing and bathing activities may constitute a significant exposure route compared to direct ingestion (Brown et al., 1984). While residents have been provided bottled water for drinking, the potential for continued use of the groundwater for non-drinking purposes remains. Exposure from ingestion involves the use of the groundwater for drinking and cooking; inhalation exposure to contaminants volatilized from the water may occur during showering. Given the volatility of the chemicals and their low dermal absorption, bathing and routine washing activities do not appear to be viable exposure routes.

REPT4/tdg -20- The greatest risk to an individual is likely to occur at the private supply well with the highest contaminant concentrations; the contaminated or threatened municipal supply wells are of concern because of the larger exposed or potentially exposed population. The maximum concentrations of the contaminants of concern in groundwater in municipal wells 4 or 5, private supply wells and monitoring wells, determined during the RI or previously, are presented in Table 9-1. USEPA drinking water maximum contaminant levels (MCLs) developed under the Safe Water Drinking Act are the applicable or relevant and appropriate requirements (ARAR's) of interest to this evaluation. MCLs are maximum permissible levels of contaminants in water delivered to the user of a public water supply. MCLs represent allowable lifetime exposure levels for a 70 kg adult ingesting 2 liters of water per day. MCLGs, entirely health- based, are developed by USEPA as part of the process for setting MCLs. They represent the maximum concentrations of contaminants in drinking water at which no known or anticipated adverse effect on the health of persons will occur, and they include an adequate margin of safety. MCLGs are nonenforceable health goals. MCLs have not been established for any of the contaminants of concern. MCLGs have been established for TCE and vinyl chloride and maximum and- mean concentrations of these contaminants in groundwater exceed the goals. The other criteria considered are proposed MCLs and proposed MCLGs developed under the Safe Water Drinking Act and Minnesota Department of Health (MDH, 1986) Recommended Allow- able Limits (RALs). While MDH indicates that the RALs apply only to private water supply, they are compared to all the data presented in Table 9-1. The proposed MCL and RAL for TCE is exceeded based on the maximum concentrations, as are the proposed MCLGs and RALs for PCE and cis-1,2- dichloroethylene based on the maximum concentrations. The mean concentrations of TCE exceed the proposed

REPT4/tdg -21- MCL while the mean concentrations of PCE exceed the proposed MCLG and RAL. It is uncertain whether the proposed MCL and RAL for vinyl chloride are exceeded. In summary, contaminant concentrations in groundwater exceed federal and state guidelines for drinking water quality, Under the assumption that the evaluated wells provide the sole source of water to residents in the vicinity of the site/ concern exists for potential adverse health effects. Based on the analysis of the nine private wells sampled during the RI, the plume of contaminated groundwater remains contained within the boundaries of the Health Advisory Area. At this time, the boundaries appear to be adequate to protect private wells in the vicinity of the contaminant plume.

10.0 ALTERNATIVE RESPONSE ACTIONS The alternative response actions possible for the contamination problem identified at Long Prairie are listed in Table 10-1. They will be evaluated further during the feasibility study phase to determine which response action can effectively solve the groundwater contamination problem at Long Prairie.

REPT4/tdg -22- 1.0 INTRODUCTION

1.1 General This chapter describes the site location, provides a historical background of the problem, explains the steps in which the remedial investigation was conducted and summarizes the scope of the total report.

1.2 Site Location The city of Long Prairie, Minnesota, with a population of approximately 2,500, is situated in the Long Prairie River Valley in central Minnesota and is the county seat of Todd County. Figure 1-1 shows the location of Long Prairie and Todd County in Minnesota. Municipal water supply is not available to all City residents; some of them obtain their water supply from their own private wells. The Long Prairie Groundwater Contamination Site consti- tutes an area of contaminated -groundwater in an aquifer located below the northeast quadrant of Long Prairie. The general site area, shown in Figure 1-2, lies north of First Avenue S.E., south of the northern corporate limits, east of the Long Prairie River, and west of a north-south line super- imposed over the easternmost corporate limit. An area of contaminated groundwater lies within this area from its apparent origin behind City Hall in the center of the block bounded by First Avenue S.E., Central Avenue, Second Street N.E. and Third Street N.E. extending northeast for approximately 2,100 feet or 4 tenths of a mile, in a northeasterly direction, to the vicinity of Municipal wells 4 and 5 located near the intersection of Fourth Ave. NE and Todd St. NE.

1.3 Historical Background On August 26, 1983, as part of a state-wide program of routine groundwater sampling and analysis, the Minnesota Department of Health (MDH) obtained samples from Municipal Wells 1 through 5 serving the City of Long Prairie. Results

REPT4/tdg 1-1 \

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EXISTING MONITOR WELL LOCATIONS

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0 MUNICIPAL WELLS

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FIGURE 1-2 MALCOLM n P1RNIE of the analysis indicated contamination of Municipal Wells 4 and 5 by chlorinated ethylene compounds. On October 12, 1983, the MDH again analyzed samples from the municipal wells. Contamination of wells 4 and 5 was confirmed. Analyses showed the presence of 1,1,2,2-tetrachloroethylene at 26 and 270 ug/1 in wells 4 and 5, respectively. The wells also indicated lower levels of 1,1,2 trichloroethylene* (at 1 and 11 ug/1, respectively) and cis-l,2-dichloroethylene (at 0.8 and 16 ug/1, respectively). As a result of the contamination several immediate actions were taken. First, Municipal Wells 4 and 5 were shut down. Next, the Minnesota Pollution Control Agency (MPCA) began a search for probable sources of the contamination. Finally, the MPCA initiated a sampling program of over 90 private potable wells in the northeastern section of Long Prairie. Analytical results again confirmed contamination by PCE with concentrations up to 510 ug/1 in approximately half of the private wells sampled. The MDH issued a drinking water advisory on November 1, 1983 for residents with private potable wells in a 15 square block area of northeastern Long Prairie. Private well owners were advised to discontinue using their water for drinking and, in some cases, for all purposes. Bottled water was made available to residents in the advisory area. In November, 1983, MPCA began a program to investigate the contamination problem and to determine the best alternative for providing an adequate amount of water for Long Prairie. State funds were made available to accomplish these two tasks. As part of its investigation, MPCA had 15 monitoring wells installed in the affected part of the city to better define the extent of groundwater contamination and to locate its source.

* Called Perchloroethylene (PCE) or Tetrachlorsethane. The term "PCE" will be generally used in this report to designate this component.

REPT4/tdg 1-2 The investigation concluded that the problem originated from a long-existing dry cleaning establishment at 243 Central Avenue adjacent to the City Hall in the center of Long Prairie. That business, owned and operated by several parties over its history, will be referred to as the "dry cleaner" in this report. In the summer of 1984, remedial actions for the city's water supply were initiated by MPCA. A new municipal well, No. 6, was completed in the fall of 1984 in extreme northeast Long Prairie near the intersection of Seventh and Ninth Streets, N.E. beyond the area of known contamination. A transmission line was installed from Well No. 6 to new water mains completed in areas of northeastern Long Prairie that did not originally have them. Advanced treatment of water from Municipal Wells 4 and 5 was provided in the summer and fall of 1984 using carbon filters as a temporary measure. This was done to ensure an adequate supply of potable water while Well No. 6 was being installed. In September, 1984 the United States Environmental Protection Agency (EPA) and the MPCA executed a cooperative agreement for implementing a remedial investigation and feasibility study (RI/FS) at the site. The site was proposed for inclusion on the National Priorities List in October, 1984. On August 8, 1985, MPCA asked Malcolm Pirnie, Inc. to conduct the RI/FS for the site. A work plan to conduct these studies was prepared and submitted to MPCA on July 24, 1986. MPCA approved the work plan and authorized Malcolm Pirnie to commence RI activities on September 23, 1986. This report presents the results of these activities.

1.4 Remedial Investigation 1.4.1 Objective and Procedure The objective of the Long Prairie RI was to provide adequate characterization of the site and its actual or potential hazard to the public and environment. It was

REPT4/tdg 1-3 designed to develop sufficient data and information to determine the need for remedial action and to provide an adequate basis for developing an appropriate feasibility study (FS). The various steps involved in the RI are described below. 1.4.2 New Well Installations Up to eleven new monitoring wells were proposed in the Work Plan to further define the vertical and horizontal extent of contamination. Boring and well locations were selected to facilitate characterization of the contamination plume, further define the subsurface geology, fill in data gaps in the existing monitoring points and provide data to assess potential response actions. Clusters of wells with varying depths were proposed to determine the vertical profile of groundwater contamination by a contaminant, such as PCE, which is denser than water and tends to "sink" through the aquifer. Three of the eight new wells were "clustered" with previously existing monitoring wells although their depths were greater than those of the existing wells at the respective locations. These included monitoring wells No. IB, 2C, and 3B. Two new monitoring wells, 14A and 14B formed a new cluster at a location where no wells previously existed. As shown in Table 1-1, some of the wells proposed in the work plan were not installed due to the following reasons: MW-10A Only one well, MW-10 was installed at the and originally proposed location of MW-10A to an MW-10B: approximate depth of 21 feet. An additional deeper well was not considered necessary here due to the fairly shallow depth of the aquifer. This location was originally thought to be upgradient of the contamination sources, i.e., the dry cleaner. However, it turned out to be the most heavily contaminated monitoring well.

MW-11A Only one deep well, MW-11, was installed at the and originally proposed location to a depth of MW-11B: 56.65 feet.

REPT4/tdg 1-4 TABLE 1-1

LONG PRAIRIE REMEDIAL INVESTIGATION PROPOSED WELLS/ACTUALLY INSTALLED WELLS

Monitoring Wells Proposed Actual Proposed in Work Plan Location Location

MW-1B 1st Ave. & 2nd St. 1st Ave. & 2nd St.

MW-2C 1st Ave. near 3rd St. 1st Ave. near 3rd St.

MW-3B Post Office Post Office

MW-10A Rear, 243 Central Rear, 243 Central

MW-10B Rear, 243 Central Not installed

MW-11A 7th St. near 5th Ave. Not installed

MW-11B 7th St. near 5th Ave. 7th St. near 5th Ave.

MW-12A (optional) South of MW-10 Not installed

MW-12B (optional) South of MW-10 Not installed

MW-13 Todd St. & 4th Ave. Todd St. & 4th Ave.

MW-14B 4th Ave. & 6th St. 4th Ave. & 6th St.

MW-14C Not originally proposed 4th Ave. & 6th St.

REPT4/tdg 1-5 MW-12A The Work Plan proposed that these wells be and installed further upgradient or south of the MW-12B: probable contamination sources to determine the southerly limit of the contamination. These wells were not installed since the contaminated aquifer was not present south of MW-10 and a suitable well location was not available.

MW-14: This well was positioned approximately 200 feet west of its intended location in order to avoid overhead utility lines. Originally intended as one well, a two-well cluster was installed with the well depths of 27.95 and 56.45 feet. 1.4.3 Rehabilitation of Existing Monitoring Wells It was reported that existing monitoring well 7B had been vandalized and filled with debris. In accordance with MDH regulations, this well was abandoned since it could not be repaired. The groundwater sample taken from MW-7A during Round 1 sampling did not reveal any contamination. Therefore, a new well to replace the abandoned MW-7B was not considered necessary. 1.4.4 Waste Characterization At the time of the work plan submittal, the original monitoring wells installed by MPCA had last been sampled in February 1984, soon after their installation. Additional sampling and analyses were considered necessary to determine whether there had been any significant changes in groundwater quality since the February, 1984 sampling. The work plan proposed three rounds of groundwater sampling and analysis. In all rounds, the sampling techniques and chain of custody procedures were in accordance with the QAPP. The first round of groundwater sampling was performed on all existing monitoring wells, Municipal Well Nos. 3, 4, 5, and 6, and nine selected private wells in the affected area as listed in Table 1-2. The samples were analyzed for volatile constituents using EPA Method 601. Confirmation analysis was performed on those Round 1 samples showing contamination in order to distinguish between co-eluting parameters.

REPT4/tdg 1-6 TABLE 1-2

LONG PRAIRIE REMEDIAL INVESTIGATION WELLS SAMPLED DURING ROUND 1

Existing Monitoring Wells Location

la 1st Ave. & 2nd St. (city lot)

2a 1st Ave. & 3rd St. 2b (liquor store)

3a Post Office (along alley)

4a 4b 3rd Ave. & Todd St. 4c (ball field)

5a 5b Old city dump site

6a 4th St. & 2nd Ave. 6b Left/west side 6c Right/east side

7a Hockey Rink

9a 632 ft. S. of County Rd. 27

BAL-2b North side of Muni. Well 6 BAL-2c In field, 200 ft. west of cemetery/fairgrounds

Residential Wells:

Schroeder 610 5th Ave. Werner 216 6th St. NE Plemel/Sundberg 405 6th St. NE Werlinger 410 1st Ave. N Barren 124 1st Ave. N Mueller 314 6th St. Hokanson 116 6th St. Neidhart 321 3rd Ave. Starry 602 6th St. NE

Municipal Well #3 1st Ave. NE & 8th St. NE Municipal Well #4 4th Ave. NE & Todd St. NE Municipal Well #5 4th Ave. NE & Todd St. NE Municipal Well #6 7th St. NE & 9th St. NE

REPT4/tdg 1-7 After the new monitoring wells were completed, a second round of sampling was conducted. This second round included the eight new monitoring wells and the existing monitoring wells BAL-2B, 6C and municipal well 6. These last three wells were added to the second round of sampling because of the slight levels of PCE detected in BAL-2B during Round 1. It was desired to confirm any contamination in BAL-2B and to determine the presence of any contamination in Municipal Well 6 located near BAL-2B and currently being used for supplying potable water. Monitoring well 6C was sampled in the second round in place of an upgradient well which was not installed. During the second round of sampling, groundwater samples for full HSL analysis were obtained from MW-10 and MW-6C. Based on previously available data, non-volatile contaminants were believed to be absent in these wells; the HSL analyses confirmed it. These two monitoring wells were selected for HSL analysis because the highest concentration of contaminants were suspected at these locations based on analytical information from the first round of sampling and information. Following receipt of analyses from the second round, a third round of sampling was conducted. These samples were obtained from the 16 previously existing monitoring wells originally sampled in the first round, and the eight new monitoring wells sampled in the second round. Thus, existing and new monitoring wells were each sampled at least twice. Analytical data from the third round of sampling was used to confirm the presence and levels of contaminants detected in the earlier rounds. 1.4.5 Well Measurements Water level measurements of all wells were taken immediately following the installation of the new wells, during all rounds of sampling, and between sampling rounds, for a total of five times during the RI. These measurements were taken to develop groundwater contour maps and to show fluctuations of seasonal water levels.

REPT4/tdg 1-8 A level survey of the casing tops of all wells was conducted following installation. The resulting top of casing elevations of all wells are given in Chapter 4.0. Significant differences between elevations of the existing wells given in Table 1-1 of Chapter 1 of the work plan and those resulting from this level survey were found. However, in view of the greater accuracy of the current level survey, the elevations generated during the RI were utilized in this report. 1.4.6 Pump Test A constant rate pumping test on municipal well no. 4 was conducted to obtain data which would help determine the following: o Aquifer transmissivity (the rate at which water will flow through a one-foot wide vertical strip of the aquifer under a gradient of 1.0), and o Storage coefficient (the volume of water released from storage from a one cubic foot portion of the aquifer). These parameters are useful in calculating the rate of contaminant movement through the aquifer and in determining the ultimate fate of the contaminants in the aquifer. The data derived can also be used in the design of remedial alternatives. Six groundwater samples were obtained at five intervals during the pump test for volatile organics analyses. 1.4.7 Soil Monitoring The Work Plan called for drilling a test boring at all locations where clusters of monitoring wells were to be installed. Split-spoon soil samples were to be collected at two-foot intervals. Test borings were conducted at all cluster and single well locations. However, in order to increase the rate of drilling, the number of split-spoon samples were reduced in areas of homogenous soil conditions and in areas where the presence of high levels of contaminants was considered unlikely.

REPT4/tdg 1-9 In addition to the soil borings completed at the cluster and single well locations, two soil borings were conducted in the back lot along the south wall of the dry cleaning building as outlined in the work plan (Figure 1-3). The purpose of these soil borings was to help determine whether this building was the source of the contamination. It was thought that spills from processing operations were most likely to have occurred in the area immediately behind the building in the area of the proposed soil borings. A soil sample obtained from the second boring labeled as TB-A was subjected to a complete Hazardous Substance List (HSL) analysis. Results of this sampling were compared to other results to further detail the nature of the contamination problem. A third test boring labeled as "TB-C" was conducted approximately 50 feet directly south of TB-A and 25 feet east of MW-10. A soil sample from this boring was analyzed for the volatile fraction of the HSL. Both boring locations are shown on Figure 1-3. 1.4.8 Analytical Methods Groundwater samples collected from previously existing monitoring wells, municipal wells No. 3, 4, 5, and 6, and nine domestic wells as listed in Table 1-2 were analyzed using USEPA Method 601 for volatile organic chemicals by PACE Laboratories as outlined in the QAPP. After the proposed monitoring wells were constructed, the new wells were sampled and analyzed using Method 601 for volatiles during Round 2. Certain groundwater and soil samples were analyzed using Contract Laboratory Program (CLP) procedures for HSL parameters also as described in the QAPP. Analytical procedures were also in accordance with the QAPP. 1.4.9 Identification of Method of Release It was originally thought that the source of contamination was within the dry cleaning building and probably due to spills which entered the groundwater through the building's basement. However, investigative activities were conducted which indicated that the most likely source of contamination

REPT4/tdg 1-10

is instead a partially buried drum found at the extreme rear of the lot behind the dry cleaning building adjacent to the back wall of the Armory building. These activities included analyses of a soil/waste sample from within the drum and soil from two nearby test borings. A groundwater sample from monitoring well 10 also showed extremely high levels of contamination. These four locations are located upgradient of the dry cleaning building. The drum appeared to be used directly for the disposal of liquid wastes and perhaps ash from a small brick kiln located immediately adjacent to the drum.

1.5 Overview of this RI Investigation Report This report includes the following sections: 1.0 Introduction 2.0 Site Features 3.0 Hazardous Substances Investigation 4.0 Geologic and Hydrogeologic Investigations 5.0 Surface Water and Sediment Investigation 6.0 Air Investigation 7.0 Biota Investigation 8.0 Bench and Pilot Studies 9.0 Public Health and Environmental Concerns 10.0 Bibliography Appendices A - Boring Logs B - Monitoring Well Construction Data C - Aquifer Test Plots D - Pump Test Drawdown and Recovery Data

REPT4/tdg 1-11 2.0 SITE FEATURES

2.1 Data Sources Information and data used in the preparation of this Remedial Investigation Report have been obtained from several sources. Important documents relating to past activities have been made available by the Division of Solid and Hazardous Wastes of the Minnesota Pollution Control Agency. Such documents include, among others, analytical results of state- conducted sampling surveys, reports of the February, 1984 drilling program, and results of investigations of the source of groundwater contamination. Information based on personal experiences of Messrs Mark Lahtinen and Dale Thompson, MPCA's Project Manager and Technical Analyst, respectively, for this project has also been useful in preparing the work plan and this report. All available published data and the results of previous site investigations along with other relevant information have been reviewed. To aid site reviews and evaluation, an annotated bibliography of this information was compiled which appears at the end of this report.

2.2 Regional and Local Physiography The City of Long Prairie is located in a broad valley, approximately one mile wide, that trends north-south. The valley is bordered on the east by hills of the St. Croix Moraine and on the west by a gently undulating till plain (Figure 2-1). The elevation of the hills bounding the valley is approximately 70 to 90 feet greater than the elevation of the valley floor. The small hills extend out as a spur from the St. Croix Moraine and lie due east of a valley which drains the interior of the Wadena till plain. The Long Prairie River flows east from this tributary valley and then turns and flows to the north out of the city.

REPT4/tdg 2-1 45' 94*30' I

96*00'

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10 MILES

10 EXPLANATION CZ3 Outwash O 'Red* drift EH] "Grey* drift — Geologic contact

Boundary Locations From Schnaldtr (1961)

MAl.COl.ll •m»lf. INC. MAUDCXM SURFICIAL GEOLOGY OF THE LONG PRAIRIE REGION FIGURE 2-1 PIRNIE (TAKEN FROM MYETTE. 1884) 2.3 Regional Geology 2.3.1 Unconsolidated Deposits The City of Long Prairie is located on a long, narrow, glacial outwash plain commonly referred to as the Long Prairie Sand Plain. The sands and gravels of the Long Prairie Sand Plain were most likely deposited by outwash streams during the retreat of the Rainy/Superior glacial lobes. West of the Long Prairie Sand Plain lies the Wadena Till Plain which was deposited by the Wisconsin glacial advance. Immediately following the deposition of the broad till plain, meltwater erosion led to the formation of a tributary valley which drains the interior of the till plain into the Long Prairie Sand Plain. The till plain deposits are composed of an unsorted mixture of sand with varying amounts of clay, silt, gravel and boulders and are commonly referred to as the "gray drift" due to their characteristic gray color. The St. Croix Moraine, located east of Long Prairie, was deposited by the western-most advance of the Rainy/Superior glacial lobes. The north-south trending St. Croix Moraine ranges from three to six miles wide and is from 50 to 200 feet higher than the surrounding terrain. The moraine is composed of an unsorted mixture of sand with clay, silt, gravel and boulders. These sediments have the red color typical of Superior Lobe deposits. 2.3.2 Bedrock The glacial deposits are reportedly underlain by Precam- brian igneous and metamorphic bedrock (Kanivetsky, 1978). The rocks lack primary porosity and may not function as aquifers. Some successful wells are reported in areas where the rocks have been faulted or fractured, but even under these conditions groundwater occurrence is highly uncertain.

2.4 Local Geology The site covers the northeast portion of the City of Long Prairie. A detailed description of the geology in this area has been developed based on data from 17 monitoring wells and

REPT4/tdg 2-2 two test borings. As part of an earlier study a geologic block diagram was developed using these data (Figure 2-2). Malcolm Pirnie has reviewed the geologic data from test borings and monitoring wells and has found this diagram to be consistent with the available data. As depicted in Figure 2-2 the uppermost geologic unit is a silty sand with some coarser sand and gravel. This is the glacial outwash deposit that is the most prolific aquifer in the area. These sediments range from 7 feet thick at the location of Test Boring No. 8, to 56 feet thick at Municipal Well No. 6 and up to 66 feet thick in the vicinity of Monitor- ing Well BAL-2. This silty sand unit contains scattered, discontinuous clay lenses such as those represented at well location No. 4 and wells BAL-1 and BAL-2. Underlying the glacial outwash sediments is glacial till composed of sandy clay with varying concentrations of gravel. This unit is labeled "blue clay" on Figure 2-2, but is actually described as a gray clay in the logs of all wells except BAL-1 and BAL-2. The till appears to extend to a depth of at least 200 ft below ground level (bgl) and appears to be continuous beneath the site . The glacial till is reportedly underlain by Precambian igneous and metamorphic rocks (Kanivetsky, 1978). The bedrock is not considered an aquifer and there are no records of any wells in this rock unit in Long Prairie.

2.5 Regional Hydrology and Hydrogeology 2.5.1 Surface Water Hydrology The City of Long Prairie lies on the banks of the Long Prairie River. The river flows into the City from the west- northwest and turns approximately 110 degrees to the north, flowing almost due north when it leaves the city. There are no discharge records for the river at Long Prairie. However, approximately 12 miles upstream from Long Prairie at the gaging station near Osakis, the average annual discharge is 95 cubic feet per second (cfs). Therefore, it is safe to assume

REPT4/tdg 2-3 Geologic Block Diagram Northeastern Long Prairie

'30O-,

3) Municipal Well

4 Monitoring Well

MALCOLM riBMIf. INC MALJOOUV1 Geologic Block Diagram PIRNIE Northeastern Long Prairie FIGURE 2-2 that the average annual discharge at Long Prairie is greater than 95 cfs. The Long Prairie River is part of the Crow Wing River drainage basin which is in turn tributary to the Missis- sippi River. Wetlands in the study area lie within the lowermost floodplain of the Long Prairie River as shown on the USGS Long Prairie Quadrangle topographic map. This area is below the 1,290 foot contour line, between municipal wells 4 and 5 and the town DPW area. 2.5.2 Hydrogeology The poor permeability of the upland tills of the St. Croix Moraine and Wadena Till Plain retards percolation of precipitation into the underlying sediments. The low permeability of these deposits results in many lakes at an elevated height on uplands. These deposits lie on either side of the Long Prairie Sand Plain, a highly permeable deposit which is the most productive aquifer in the area. The aquifer is composed of stratified sands and gravels deposited by glacial runoff waters during the last glacial retreat. Across the area the outwash deposits range from 7 to 66 feet thick. In June 1984 a pumping test was conducted by Bruce A. Liesch Associates at Municipal Well No. 6, which is completed in the outwash aquifer. The well was pumped for 72 hours at a constant rate of 425 gallons per minute. Based on data obtained during this test the transmissivity of the aquifer was calculated to range from 25,600 gallons per day per foot (gpd/ft) at BAL-2c using the "Steady State Leaky Artesian Method", to 312,000 gpd/ft at BAL-2b using a Time-Drawdown Method. The transmissivity values calculated from the BAL-2c drawdown data using the "Steady State Leaky Artesian Method" (25,600 gpd/ft) and the "Non-Steady State Leaky Artesian With Storage Method" (48,705 gpd/ft) were determined to best represent the hydraulic characteristics of the aquifer (Liesch, 1984b). The aquifer storativity was also calculated using the "Non-Steady State Leaky Artesian With Storage Method" and determined to be 3.5 x 10 . The storativity value of 10

REPT4/tdg 2-4 suggests that the aquifer in which Well No. 6 is screened is under artesian conditions, meaning that there is a confining unit between this zone and land surface. However, geologic logs of test borings and monitoring wells at this site indicate that the clay stratum encountered at 41 to 55 feet bgl at Well No. 6 is not continuous or areally extensive. The pumping test data used to determine the storativity value should be reevaluated to resolve this apparent discrepancy. The aquifer hydraulic parameters discussed above are based on pumping test data from a test conducted at Municipal Well No. 6. Therefore, the values presented above are valid only for the aquifer zone that No. 6 is screened in and only for the portion of that zone near Municipal Well No. 6. Groundwater flow at the site has been evaluated using data from existing monitoring wells. Locations of these wells are shown in Figure 1-2. Construction details for these wells are presented in Table 1-2; and fluid-level data are presented in Table 1.2 of the work plan. A groundwater contour map representing groundwater flow conditions has been developed based on groundwater elevations measured on December 9, 1985 (Figure 1.4 work plan). This map was drawn using the groundwater elevations in the shallowest wells ("a" wells) at cluster well locations, neglecting the small differences which may be caused by vertical head distri- butions. As illustrated in Figure 1.4 of the work plan, groundwater flow is to the north and west, discharging into the Long Prairie River. All groundwater at the site eventually discharges to the Long Prairie River with the exception of 1) that water which is pumped out and consumed in activities resulting in its evaporation; and 2) that water which naturally exits from the groundwater system through the process of evapotranspiration. The effect of groundwater pumpage on nearby water levels can be seen surrounding Munici- pal Well No. 6 in the northeast corner of the map. The impact that Municipal Wells No. 4 and 5 had on local flow patterns when they were pumping is shown on Figure 1.5 of the work plan (Liesch, 1984a).

REPT4/tdg 2-5 3.0 HAZARDOUS SUBSTANCE INVESTIGATIONS

3.1 Hazardous Substances, Pollutants, or Contaminants 3.1.1 Types and Locations The problem of primary importance in Long Prairie is contamination of groundwater by volatile chlorinated ethylene compounds. This contaminated groundwater regime continues to be used as a source of potable water. These volatile compounds are: o 1,1,2,2-Tetrachloroethylene o 1,1,2-Trichloroethylene o Cis-1,2-Dichloroethylene The important physical characteristics of these compounds are presented in Table 3-1. 1,1,2,2-Tetrachloroethylene or PCE is the predominant contaminant of the three in terms of concentration present at the Long Prairie site. These contaminants have been detected in repeated sampling of groundwater within the northeast quadrant of Long Prairie since August, 1983. The history of groundwater monitoring as well as analytical results are given in greater detail in Section 4.3. A review of that data indicates the following maximum values of the three contaminants were found:

MUNICIPAL PRIVATE MONITORING WELLS WELLS WELLS

1,1,2,2-Tetrachloroethylene 280 ug/1 1,000 ug/1 22,000 ug/1

1,1,2-Trichloroethylene 11 ug/1 110 ug/1 45 ug/1

Cis-1,2-Dichloroethylene 17 ug/1 250 ug/1 40 ug/1

The wells found to be contaminated are in the northeastern quadrant of Long Prairie north of First Avenue SE and east of the Long Prairie River. Isoplots showing lines of equal concentration of PCE were developed for various periods of groundwater sampling and analyses between 1983 and 1987.

REPT4/tdg 3-1 TABLE 3-1 M

LONG PRAIRIE, MINNESOTA ft Q. PHYSICAL CHARACTERISTICS OF KNOWN CONTAMINANTS iQ

BOILING MOLECULAR POINT MELTING SPECIFIC SOLUBILITY IN ORGANIC COMPOUND WEIGHT (°C) POINT (°C) GRAVITY WATER (mg/1)

Tetrachloroethylene 165.83 121 -19.0 1.6227 175

Trichloroethylene 131.29 87.0 -73 1.4642 1000

CIS 1, 2, Dichloroethylene 96.94 60.3 -80.5 1.2837 6300.0 These are given in Figures 3-1 through 3-3. A review of the isoplots shows an elongated plume of contaminated groundwater extending along a southwest/northeast axis from the center of the city to approximately Fourth Avenue NE near municipal well No. 4 at Todd Street. The plume's length is approximately 2,100 feet and its width is approximately 1,000 feet. Contam- ination appears to be throughout the saturated depth of the sand aquifer. This depth ranges from the ground surface between Central and First Avenues SE where the aquifer thins out to approximately 55 feet in depth near municipal well No. ' The isoplots indicate that the source of contamination apparently originates from the center of the city near the City Hall located on Central Avenue east of Second Street NE. Investigations were started in October, 1983 by MPCA to determine the source of the contamination. The MPCA personnel performed a preliminary review of industrial usage and records for companies using pure or nearly pure solutions of PCE. Potential sources inspected were: Hart Press, PND Cleaners, Cathedral Press, Lantz Lenses, Title Atlas Company, Minnesota Distillers, Nalewaja I Machinery, Long Prairie Leader Newspaper, Hansmann Manufacturing Company and the city dump. The Minnesota Historical Society records were also reviewed. Interviews and inspections were then conducted. Inspection of PND Cleaners at 243 Central Avenue, immediately east of City Hall revealed traces of visible spillage/leakage from dry cleaning machinery over the floor boards and onto the soil in the basement. It appeared that the release of PCE occurred at this site. Samples from the sump and well at PND Cleaners were taken for analysis of volatile hydrocarbons. Monitoring conducted by MPCA staff indicated high concentrations of VOC in the dirt area below the machinery and in the basement sump. Although soil tests did not show PCE contamination, it was concluded that PND cleaners was the probable source of contamination. This conclusion is also supported by information derived from isoplots.

REPT4/tdg 3-3 LEGEND

LIMITS OF HEALTH ADVISORY ARE/

500ug/jpCE CONCENTRAT|ON CONTOUR

2.0 CONCENTRATION OF PCE (ug/D

< BELOW DETECTABLE LIMIT

MALCOLM »l«Wlf. INC MALCOLM CONCENTRATIONS OF 1.1,2.2-TETRACHLOROETHYLENE (PCE) FIGURE 3-1 PIRNIE IN PRIVATE AND MUNICIPAL WELLS OCTOBER-NOVEMBER 1983 f* atimM.«.y//' * ;* .•1:fff 1 -- ^pswv^^aE ^t ^ .AiJi;f i« >^T: I • ^

LEGEND

LIMITS OP HIALTN AOVICOMY AftIA

COHC|HTI|AT|ON CONTOUR

t.» CONCINTMATION 9f PCI (ug/l)

< ilLOW OITICTACLI LIMIT

LONG PRAIRIE, MINNESOTA MALCOLM »l«Nlt INC MAUDOUV1 CONCENTRATIONS OF 1,1.2.2-TETRACHLOROETHYLENE (PCE) RRNIE IN PRIVATE AND MUNICIPAL WELLS FIGURE 3-2 JANUARY-FEBRUARY, 1964 EXROUslATIONT

PCe-COCeNTRATION CONTOUR

290 CONCENTRATION OETPCE

1QOOug/r " ~-«3P°ff~ 500ug/l— —

MALCOLM >mNIE. NC MALCOLM CONCENTRATIONS OF 1,1.2.2-7ETRACHLOROETHYLENE (PCE! PIRNIE OCTOBER 1986-FE3RUARY 1987 FIGURE 3-3 As part of the Remedial Investigation, Malcolm Pirnie inspected the dry cleaning business in November, 1986 (now known as Long Prairie Cleaners) to verify that it was the source of the contamination. At that time, there was no direct evidence of spills or leaking pipes or tanks. The basement sump did not appear to have any leaks or cracks which would have allowed spilled liquids to pass into soils below the building. In general, the operations appeared clean and orderly. Investigation activities were also conducted in the asphalt-paved lot behind the dry cleaning operation. The back lot discussed in this section is bounded by the rear sides of the City Hall, Long Prairie Dry Cleaner, Long Prairie Leader Newspaper, and the Armory buildings. The back lot is shown in Figure 1-3. Because of constraints in the safe use of the drilling rig, subsurface investigative activities were limited to property owned by Long Prairie Cleaners. These constraints included overhead powerlines throughout the back lot and buried gas pipelines and phone cables whose locations are also shown in Figure 1-3. The area of investigation in the back lot included a 24 foot wide strip of land extending from the entire rear side of the dry cleaning building directly south to the north side of the Armory building. Three soil borings were conducted in this area to the bottom of the overlying sand layer. Borings TB-A and TB-C are shown in Figure 1-3. The third boring was converted to monitoring well 10 and is also shown in Figure 1-3. At the extreme rear of the lot adjacent to the Armory, a badly deteriorated, no longer used, brick kiln or oven was observed. The kiln is approximately 4 feet on a side and stands about 3 feet off the ground. Below and slightly in front (to the east) of the kiln is a steel drum buried in the ground so that only 2 inches of the top rim is above the ground surface. Within the drum, a gray clay-like material resembling a wet ash was also observed.

REPT4/tdg 3-4 High VOC readings were recorded for split-spoon soil samples from all boring locations in the back lot and from within the buried drum during the course of the remedial investigation. Analytical results of soil samples from borings TB-A and TB-C indicated that PCE was not present in the soil sample from TB-A adjacent to the rear wall of the dry cleaning building; although it was present at a concentration of 11 ug/kg in the soil sample from TB-C. MPCA personnel obtained a sample of the material in the buried drum and submitted it to the MDH laboratory for chemical analyses. PCE was found in that waste sample at a concentration of 1,500 mg/kg. Groundwater samples were obtained twice from MW-10 located 22 feet downgradient (to the north) of the buried drum. Analyses showed PCE present at concentrations of 13,000 ug/1 and 22,000 ug/1 during the two sampling events conducted one month apart. It appears that the exact source of the contaminants is the buried drum in the back lot near the Armory. It is speculated that past operations at the dry cleaning business may have included disposing of waste PCE or PCE-contaminated materials and/or accidental spillage of PCE onto the ground behind the building. Waste materials such as spent filters or rags may have been burned in the kiln and the residue dumped in the drum. Dumping of liquid waste into the drum may also have occurred if the drum with its bottom removed or perforated was utilized for waste disposal conveyance. With the high concentrations of PCE in groundwater and soils upgradient of the dry cleaning building, it would appear that the actual operations within the building probably were not a major source of contaminants. Instead, it is more probable that dumping or spillage in the rear of the building contributed significantly to groundwater and soil contamination. 3.1.2 Physical States and Composition Wastes that are present in the buried drum behind the dry cleaner are in a solid state. This material as described

REPT4/tdg 3-5 earlier, is gray in color and has a texture similar to clay or wet ash. This material was noted only in the drum. Boring TB-C and MW-10 were 30 and 22 feet, respectively, from the buried drum. Although high VOC readings were noted in both borings, neither showed signs of the same clay-like waste material observed in the drum. Boring TB-A, 75 feet from the drum, also had high VOC readings but no signs of the waste material. The entire back lot was paved with bituminous asphalt in approximate 1967 according to city officials making it impossible to observe soil near the drum. It is likely that the waste material is present in the drum with perhaps a small amount in soils immediately surrounding the drum. Downgradient of the drum, to the north and northeast, waste materials, namely 1,1,2,2-tetrachloroethylene, 1,1,2- trichloroethylene, and cis-l,2-dichloroethylene are present in groundwater. The highest concentration of PCE noted in groundwater was in a sample obtained from MW-10 just 22 feet downgradient from the drum. Elsewhere, PCE was generally noted in concentrations one or two orders of magnitude less than in MW-10. 3.1.3 Quantities MPCA personnel reviewed records of several chemical suppliers including Worum Chemical, Weinberg, Inc. and Schloff Chemical for sales of PCE to the dry cleaners. MPCA found that the volume of PCE delivered varied from 606 to 131 gallons per year. For a typical small operation such as the dry cleaner, chemical suppliers indicated an estimated normal usage to be about 250 to 700 gallons per year. This information gives some indication of the probable amount delivered to the dry cleaner. It is presumed that the majority is volatilized in the cleaning process or recovered. An estimate for determining the quantity of PCE in groundwater involves multiplying the volume of contaminated groundwater by its associated concentration of PCE to obtain

REPT4/tdg 3-6 the weight or volume of PCE within that total volume of groundwater. It is recognized, though, that this method of providing an estimate is directly related to the level of detail of the data used in the calculations. For Long Prairie, a grid system was delineated over the area of affected groundwater. The grid spacing was 220 feet in the east/west direction and 260 feet in the north/south direction. The origin (or southeast corner) of the grid coincided with the buried drum. Within each "box" of the grid, the depth of saturated thickness was determined from past field observations. Using an effective porosity of 0.30 determined from the hydrogeolo- gical investigation, the volume of groundwater within each square "column" was calculated. Appropriate contaminant concentrations were then associated with each of 24 grid columns which covered the affected area. The data was obtained from past analyses performed during the remedial investigation. By multiplying the volume of groundwater in each column with the column's PCE concentration, the amount of PCE in each grid column is determined. After adding these amounts for all grid columns results, a total of 552 pounds of PCE was found present in groundwater in northeastern Long Prairie. This converts to approximately 40 gallons of PCE distributed throughout the contaminated aquifer. Since the levels of 1,1,2-trichloroethylene and cis-1,2-dichloroethylene are much lower than those of PCE, it would be expected that the quantities of the two would be much less than 40 gallons each. 3.2 Mediums Affected 3.2.1 Soil The area of major soil contamination is in the back lot between the dry cleaner and the Armory. Within this area is a partially buried drum which contains a clay-like waste material, gray in color and appearing like a wet ash. Analy- sis of a sample of this waste taken by MPCA personnel shows PCE at a concentration of 1500 mg/kg. Three borings, TB-A,

REPT4/tdg 3-7 TB-C and MW-10 installed within the back lot indicated high readings of volatile organics. Depths of the borings were 14, 14, and 25 feet respectively. However, analysis of a soil split-spoon samples from TB-A did not show PCE contamination present. Other contaminants such as fluoranthene and pyrene were found present. These are likely attributed to the presence of asphaltic materials and perhaps charred debris that may have been used as fill material. These contaminants are readily sorbed to soil particles and would not be expected to migrate through groundwater. These were not considered a major problem. Analysis of a soil sample from TB-C, 32 feet from the buried drum, showed PCE present at 11 ug/kg. Analyses of non-volatile materials was not performed for this soil sample. The volume of contaminated soil cannot be fully determined at this time. An estimate can be made assuming an overall average depth of 15 feet of contaminated soils and lateral extent of contamination being 50 feet to the north and 50 feet to the east. The resulting volume is 37,500 cubic feet of soil. 3.2.2 Groundwater A plume of contaminated groundwater extends from the lot between the dry cleaner at 243 Central Avenue to approximately Fourth Avenue NE near Municipal Well 4. The length and width of the plume are approximately 2,100 and 1,000 feet, respectively. The highest values of PCE, the major contaminant, were found near the buried drum behind 243 Central Avenue. A PCE concentration of 22,000 ug/1 was indicated in one groundwater sample from well No. 10 near that location. Levels of PCE further downgradient are lower by one or two orders of magnitude. Isoplots showing lines of equal PCE contamination are given in Figures 3-1 through 3-3.

REPT4/tdg 3-8 3.2.3 Surface Water Although no surface water samples were taken during the remedial investigation, surface water contamination is not presently anticipated given the present nature of the groundwater contamination problem. Limited surface water contamination may occur as a result of waste materials being washed from the drum in the back lot into storm sewers and subse- quently into the Long Prairie River. Because the back lot is paved with asphalt, however, most precipitation would be prevented from contacting waste materials in soils underneath the basement on the back lot. 3.2.4 Air No known ambient air contamination exists in Long Prairie as a result of the groundwater contamination by PCE. Localized contamination may exist if the waste material in the buried drum or contaminated soils are disturbed. • 3.3 Pathways of Migration/Sources of Release Based on a review of background information and results of the remedial investigation, it appears the major source of release of contaminants was through dumping or spillage of PCE contaminated wastes on to soils in the back lot of the dry cleaner. It is probable that PCE wastes were either discharged to the soil through the partially buried drum or were simply spilled on the ground prior to its being paved. Spills or leaks from within the dry cleaning building may also account for some of the groundwater contamination noted downgradient. However, because of the large concentrations found in Monitoring Well 10 located upgradient of the building and just 22 feet down gradient of the drum, it appears likely that the area around the drum is the most likely source of the contamination. A soil boring was conducted further south of the buried drum in front of the Armory building on First Avenue SE. No evidence of contamination was found here although it is noted that the contaminated aquifer thins out between the back lot and First Avenue SE precluding migration of any contaminants in a southerly direction.

DFPT4'tdc 3-9 3.4 Waste Component Characteristics This section will focus on four chemicals of concern to the Long Prairie RI. Three of the chemicals, tetachloroethy- lene (PCE), trichloroethylene (TCE) and cis-1,2-dichloroethylene have been detected in groundwater underlying the northeast quadrant of Long Prairie since 1983. The fourth, vinyl chloride, has been detected below the quantitation limit in one municipal supply well and a number of monitoring wells. 3.4.1 Environmental Transformation Degradative transformation of PCE through TCE and through one or more dichlorethylene intermediates such as cis-1,2- dichloroethylene and 1,1-dichloroethylene, to vinyl chloride has been suggested (Science Applications International Corpo- ration, 1985). The transformation of these compounds in groundwater may occur through biological processes; many factors such as temperature and pH, the type and numbers of microorganisms present and the chemical concentrations may affect the transformation or the rate of transformation. In soils, especially in soils of low organic content, the chlorinated ethylenes will leak into groundwater. PCE and TCE adsorb to soils with high levels of organics; sorption is probably an insignificant fate process for cis-1,2-dichloroethylene and vinyl chloride. It is unclear if PCE and TCE bound to organic material can be degraded by microorganisms or if they must be desorbed to be degraded. The most important transport and fate process for the chlorinated ethylenes in the upper layer of soil and surface water is volatilization into the atmosphere where they can react with hydroxyl (OH~) radicals to produce hydrochloric acid, carbon monoxide, carbon dioxide and carboxylic acid. The chlorinated ethylenes can be bioaccumulated to some degree and there is some evidence that they can be metabolized by higher organisms. Bioaccumulation and biodegradation do not appear to be important environmental fate processes for vinyl chloride (Clement Associates, Inc., 1985).

REPT4/tdg 3-10 3.4.2 Pharmakokinetics, Metabolism, and Toxicity A summary of information on the metabolism and toxicity of the chemicals of concern is presented by chemical. While detected in groundwater in only trace quantities at present, information on vinyl chloride is presented due to the likely environmental transformation processes discussed earlier. The metabolism and relative reactivity of the metabolic products of chlorinated ethylenes are of interest because of evidence that the metabolites are the cause of functional impairment and tissue damage in various organs (National Academy of Sciences, 1983). The symetrical chlorinated ethylenes, including PCE, are postulated to be more resistant to metabolism and to the formation of reactive intermediates than are the unsymmetrical members of the series (Politzer et al., 1981 as reported in National Academy of Science, 1983). It is thought that the hepatotoxicity of the chlorinated ethylenes is inversely related to the stability of the compound to biotransformation. The first step in the metabolism of the chlorinated ethylenes is postulated to be the formation of an epoxide, a highly reactive intermediate with alkylating properties. Tetrachloroethylene or PCE (CC^CCl^) - PCE is a moder- ately volatile chlorinated hydrocarbon which has important applications in the dry cleaning of fabrics and in the degreas- ing of fabricated metal parts. It is nearly insoluble in water but is highly lipophilic. PCE is rapidly and virtually completely absorbed following oral administration, presumably because of its lipid solubility; pulmonary uptake of PCE during inhalation exposure is linearly proportional to exposure duration and the concentration in air. Absorption of PCE during vapor or liquid contact with the skin of experimental animals or man is very slow (USEPA, 1985). PCE distributes widely into body tissues and readily crosses the blood brain barrier and placental barrier.

REPT4/tdg 3-11 PCE metabolism in man and animals is rate dependent (metabolism decreases with increases in dose) and saturable. While limited metabolism of PCE occurs, the principal site of metabolism is in the liver where PCE is oxidized to PCE oxide which rearranges to trichloroacetic acid. PCE metalolites have been shown to covalently bind to cellular macromolecules such as protein and lipid. Cumulative cellular changes may result in humans subject to chronic exposure since tissue- bound metabolites have a slow rate of turnover. Covalent binding and hepatotoxicity of PCE are directly proportional to metabolized dose. Most of the human toxicological data for PCE is derived from accidental and occupational exposures to high, often unknown, ambient concentrations. Although a wide variety of toxic effects have been observed, the effects on the central nervous system are the most noticeable. Effects on the liver and kidneys, some of which have occurred after an enlapsed period of time, have also been noted (USEPA, 1985). The effects are similar to those observed in laboratory animals following acute, subchronic and chronic exposure to PCE. Additional adverse effects in humans may include irritation of the mucous membranes and intoxication. The mammalian tests performed to date do not indicate any significant teratogenic potential of PCE; the teratogenic potential of PCE for humans is unknown. Although mutagenicity studies of PCE in microbial test systems have produced inconclusive or negative results, PCE epoxide, a reactive metabolite of PCE, has been found to be mutagenic. Negative results were obtained in one in vivo cytogenetics study in humans (Ikeda et al., 1980 as reported in National Academy of Sciences, 1983). The USEPA classifies PCE as a Group B2 probable human carcinogen via both oral and inhalation routes of exposure. The classification is based on the results of a bioassay conducted by the National Cancer Institute in which PCE administered by gavage increased the incidence of liver tumors in mice, the results of a bioassay conducted by the National REPT4/tdg 3-12 Toxicology Program in which PCE administered through inhalation was shown to induce carcinogenic effects in both rats and mice, negative results in a number of other animal studies and mixed results from a number of short-term studies designed to evaluate mutagenic potential (USEPA, 1986) . It is generally recognized that the carcinogenic potential of PCE resides in its biologically reactive metabolites rather than in the PCE compound itself and the tumorigenic response is assumed to be directly related to metabolized dose. Human epidemiological investigations of PCE carcinogenicity are marred by problems in design and methodology and by lack of adequate exposure data. These studies have primarily been carried out on people employed in the dry cleaning and laundry industries and suggest an increased risk of pancreatic and kidney cancers (USEPA, 1985). In terms of relative potency, PCE ranks in the lowest quartile among 55 suspended or known carcinogens evaluated by the USPEA Carcinogen Assessment Group. Trichloroethylene or TCE (CHCICCI^) - The pharmakokinetics and metabolism of TCE have been studied in man as well as in animals. TCE absorption after oral ingestion is virtually complete; TCE absorption from inhalation increases in proportion to the duration of exposure and concentration in air (USEPA, 1985). The compound distributes widely into body tissues and is eliminated via liver metabolism to urinary metabolites. In man, metabolism of TCE is linearly proportional to the inhaled dose and there is no indication that the metabolism is saturation dependent. While studies have not been made of TCE metabolism in man after oral exposure, at the concentrations typically found or expected in drinking water, TCE is expected to be completely absorbed and metabolized. Metabolic processes are similar to those described for PCE; TCE metabolism proceeds at a much slower rate in humans than in laboratory animals.

REPT4/tdg 3-13 While the teratogenic potential of TCE for humans cannot be directly extrapolated from animal studies, exposure of various gestating laboratory animals to levels greatly in excess of those generally found in the environment has not been observed to result in any teratogenic effects. Available data provide suggestive evidence that commercial grade TCE is a weakly active, indirect mutagen causing effects in a number of different test systems. The USEPA classifies TCE as a Group B2 probable human carcinogen (sufficient animal evidence of carcinogencity and inadequate human evidence) via both oral and inhalation routes of exposure. Some uncertainty exists, however within the national and international scientific communities as to the classification of TCE as a carcinogen. The interpretation of the incidence of liver tumors in studies involving male mice is the cause of the uncertainty. The induction of tumors in both sexes of mice in multiple studies, the incidence of other tumor types in mice, some evidence of mutagenicity and binding with DNA are the bases of the conservative classification. There are no adequate epidemeologic data in humans. The carcinogenic potential of TCE is generally considered to reside in cellular-reactive intermediate metabolites. Based on relative potency, TCE ranks in the lowest quartile among the 55 suspect or known carcinogens evaluated by the USEPA Carcinogen Assessment Group. cis-l,2-Dichloroethylene (C1CHCHC1) - 1,2-Dichloro- ethylene exists in both the cis and trans forms. Based on studies with TCE, virtually complete absorption of cis-1,2- dichloroethylene from oral exposure can be assumed. It has been demonstrated in an isolated, perfused rat liver preparation that both isomers are metabolized to the same metabolites, dichloroacetic acid and dichloroethanol, apparently via an epoxide entermediate (Bonse et al., 1975 as reported in National Academy of Science, 1983).

REPT4/tdg 3-14 Both isomers demonstrate a potential for liver and kidney damage, although little information is available on the effects of these compounds from chronic exposure They possess general anesthetic and narcotic properties at exposure levels above those at which liver and kidney effects are seen. Data on the human health aspects of exposure to cis-1,2-dichloroethylene are unavailable Cis-1,2-dichloroethylene was non- mutagenic when assayed with E. coli, found to be mutagenic in the host-mediated assay using Salmonella tests stains in mice and produced chromosomal abberations in mouse bone marrow cells following intraperitoneal injections. Data are lacking on the teratogenicity and carcinogenicity of 1,2-dichloroethylene. Long-term studies on the carcinogenic potential of cis-1,2-dichloroethylene have not been carried out and the compound is in Group D not classified in the USEPA weight of evidence categories for potential carcinogens. Vinyl Chloride (CH^CHCl) - Rapid absorption of vinyl chloride from the gastrointestinal tract into the blood of dosed rats has been reported (USEPA, 1984) . Vinyl chloride has been known to have carcinogenic effects in humans and animals from both oral and inhalation routes. It is a Group A human carcinogen (sufficient evidence from epidemiological studies) in the USEPA weight-of evidence categories for potential human carcinogens. In humans, exposure to vinyl chloride is associated with angiosarcoma of the liver. Several tumor types have been reported in animals following exposure to vinyl chloride through ingestion or inhalation. In addition to the liver, organs most likely to be affected are the brain, lung and hemato- and lymphopoietic systems. Toxicity and carcinogenicity are mediated through a metalobic intermediate, with the incidence of effect related to the amount of vinyl chloride metabolized rather than to the concentration of exposure. Vinyl chloride has also been shown to bind to DNA in short-term studies.

REPT4/tdg 3-15 Data regarding the teratogenicity of orally administered vinyl chloride are generally not available, however it was not teratogenic when administered via inhalation to rats, mice or rabbits (USEPA, 1984). Data are inadequate to characterize the teratogenicity of vinyl chloride to humans.

REPT4/tdg 3-16 4.0 GEOLOGIC AND HYDROGEOLOGIC INVESTIGATION

4.1 Site Specific Geology The City of Long Prairie is located on and around a small hill which extends west from the St. Croix Moraine. This spur of the St. Croix Moraine is due to the Long Prairie River valley having cut into the Wadena Till Plain directly west of the city. This pre-existing east-west valley allowed advancing ice of the Rainy/Superior glacial lobes to extend to the west further at this point than at other points along the east wall of the Wadena Till Plain. As a result, subsurface till deposits in the area extend from the St. Croix Moraine towards the tributary valley to the west. The western-most surface expres- sion of this subsurface extension is the hill upon which the Todd County Court House is built. Numerous borings in the work area have shown that the outwash sands and gravels lie as an arcuate wedge curving from a north-south orientation on the west wall of the St. Croix Moraine to a east-west orientation on the north side of the till spur. The outwash sands and gravels thicken both to the north from the town center and to the west from the till hills lying to the east. These outwash sands and gravels are generally well washed but may contain isolated lenses of silty fine sand or clay. North of the town center the outwash sands and gravels quickly thicken as the underlying till drops off steeply. At the Todd County Court House the till goes from a near surface or possible surface exposure to a depth of 50 to 60 feet within one half mile. An impermeable layer extends west from the area of municipal well 6 at a depth of approximately 40 feet. The density of this material seems to indicate that it is a till deposit versus a lacustrine (lake) clay deposit. While conclusive evidence is lacking, it may be a manifestation of a minor readvance of the Rainy/Superior glacial lobes over outwash sands already deposited in the Long Prairie Sand Plain or a substantial body of flowtill deposited during the retreat

REPT4/tdg 4-1 of the Rainy/Superior glacial lobes. If this deposit was formed during retreat of the last glacial ice as a flowtill, there may be associated soft clay lacustrine deposits not encountered by the drilling program. This deposit pinches out to the west near the location of municipal wells 4 and 5 and to the south between monitoring wells 4 and 6. 4.1.1 Test Borings, Logs, Cross Sections An expansion of the previously existing groundwater contamination monitoring program was implemented in November 1986. Boring and well locations were selected to facilitate characterization of the contamination plume, further define the subsurface geology, fill in data gaps in the existing monitoring points and provide data to assess potential response actions. A total of ten test borings were drilled by hollow stem auger. Safe operation of the drill rig necessitated switching over to mud rotary tri-cone drilling on a few of the deeper bore holes. All borings were logged in the field. Full geologic descriptions are given in Appendix A. The logs have been set up in columns headed by sample number and depth, blows/six inches, soil sample recovered and sample length, material moisture and water table (feet), soil density (USGS), color, soil description and remarks. Hollow stem split spoon samples were collected and also screened with a HNu for volatile hydrocarbon compound presence. Collected samples were later used to make USCS and Munsell soil color designations included in the boring logs. The test boring logs were used to generate cross sections representative of the area geology. Boring columns were scaled vertically and placed on a horizontal scale oriented to the three section lines shown on^fc^HM^Bi* Tne boring columns are corrected with respect to mean sea level datum and geologic interpretations and are made to fill in the area between the boring columns to complete the cross sections. Cross sections provide a graphic representation of subsurface conditions within the study area. The information presented on a cross section is generally more accurate closer

REPT4/tdg 4-2 _ -LL^JO1 J ^"V'V "H • • . h-T'^rrA-i !

LONG PRAIRIE REMEDIAL MALCOLM PlftNlt. INC. INVESTIGATION REPORT PIRNIE WELL LOCATIONS AND FIGURE 4-1 LINES OF SECTIONS to the boring columns, therefore a cross section is more reliable if the represented soil borings are more closely spaced. The cross sections along A-A1, B-B', and C-C1 are given in Figures 4-2, 4-3, and 4-4 respectively. Borings drilled at seven of the locations served the additional purpose of aiding in proper monitoring well installation. Of these seven wells, Wells 1C, 2C, 3B, 14A and 14C were placed in existing or new well clusters while Wells 10, 11C and 13C were single wells. One boring was used for collection of a soil sample and the remaining three borings were used solely for further definition of the subsurface geology. Information regarding previously existing and new wells is given in Table 4-1. At the well clusters the shallow wells ('a' wells) were installed at the water table; the deep wells ('c* wells) were installed at or near the aquifer base and the mid-depth wells ('b' wells) were installed at the approximate middle of the aquifer. Clustering of wells in this manner allows for monitoring of groundwater at more than one stratigraphic zone. Wells 10 and 14B were installed with a hollow stem auger at the same time the borings at these locations were drilled. A sand filter was emplaced in the annular space between the well screen and the boring wall, a 2 foot bentonite pellet seal was placed above this sand pack and the remaining annular space in the boring was grouted with a bentonite/cutting mix. All other wells were cable-tool driven. Driven wells, as a result of their method of emplacement require no sand pack or grouting. All wells were cemented at the surface, installed with locking caps and surrounded with guard posts. Locking caps were installed on monitoring wells BAL-2B and BAL-2C as outlined in the work plan. Monitoring well construction data for each well appear in Appendix B.

REPT4/tdg 4-3 .LAND S.E.R.F.AC.E.

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1 2E7-.VEE;. V/IDS'.Y S?i.C£0 5O?.iJ:C3. ACTUAL rlELO OUTVVASH SAND CONDITIONS WILL VA.PY raow THOSE SHOV/M 3) GENERALIZED SOIL DESCRIPTIONS ARE SHOWN BETWEEN STRATUM LIMES. FOR MORE DETAILED TILL DESCRIPTIONS REr£S TO ACTUAL WELL AND BORING LOGS ± 4) GROUNDWA7ER LEVELS WILL FLUCTUATE. FLUCTUATIONS SCREENED INTERVALS IN LEVELS WILL RESULT FROM VARIATIONS IN RAINFALL. 7ERMPERATURE. SEASON AND OTHER FACTORS AT THE TIME OF MEASUREMENT

LONG PRAIRIE REMEDIAL MALCOLM nmnc. MC. "INVESTIGATION REPORT " FIGURE 4-4 .GEOLOGIC. CROSS SECTION .C.-C1 +-3M-O- LONG.P.R.AIRIE _LANO..SE.RF..ACE •R l-V-E-f LU 1-3OO >. LU

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NOTES: 1) "HE LOCATION Or "HE GSOLOSiC CROSS SECTION IS 5KOWN ON THE LOCATION DETAIL J.IA?. FIGURE . 2) THE STRATUM LINES ARE EASED OH INTERPOLATION BETWEEN WIDE'-Y SPACED BORINGS. ACTUAL FIELD CONDITIONS WILL VARY FSOW THOSE SHOWN KEY 3) GENERALIZED SOIL DESCRIPTIONS ARE SHOWN BETWEEN STRATUM LINES. FOR MORE DETAILED OUTWASH SAND DESCRIPTIONS REFER TO ACTUAL WELL AMD SORING LOGS <) GROUNDWATER LEVELS WILL FLUCTUATE. FLUCTUATIONS IN LEVELS WILL RESULT FROM VARIATIONS IN RAINFALL. TILL TcRMPERATURE. SEASON AND OTHER 'ACTORS AT THE TIME OF MEASUREMENT SCREENED INTERVALS

MALOOUvt LONG PRAIRIE REMEDIAL PIRNIE INVESTIGATION' REPORT 'A'

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NOTES: 1) THE LOCATION OF THE GEOLOGIC CROSS SECTION. IS SHOWN ON THE LOCATION DETAIL MAP FIGURE OUTWASH.SAND 2) THE STRATUM LINES ARE BASED ON INTERPOLATION BETWEEN WIDELY SPACED BORINGS. ACTUAL FIELD TILL CONDITIONS WILL VARY FROM THOSE SHOWN • 3) GENERALIZED'SOIL DESCRIPTIONS ARE SHOWN _i_ BETWEEN STRATUM LINES. FOR MORE DETAILED SCREENED INTERVALS DESCRIPTIONS REFER TO ACTUAL WELL AND BORING LOGS_ 4]I "GROUNDWATER LEVELS WILL FLUCTUATE. FLUCTUATIONS IN LEVELS WILL RESULT FROM VARIATIONS IN RAINFALL.'. TERMPERATUREl SEASON AND OTHER FACTORS AT THE TIME OF MEASUREMENT

LONG PRAIRIE RE&r£D~I£lI MALCOLM PWMK. MC. MA1COLM INVESTIGATION REPORT. PIRNIE FIGURE 4-2 GEOLOGIC CROSS SECTION A-A1' TABLE 4-1 *>» LONG PRAIRIE WELL DATA rt

From From Total Ground Relative Top of Ground Well Total Well Nell Position Casing Ground Screen Screen Screen Depth +/or Boring Log No. In Cluster Diameter Elev. Elevation Length Depth Elevation (»»/Stickup) Depth

1A West 2" 1,296.42 1,294.26 5 9.5-14.5 1,284.76-1,279.76 16.35 18 IB East 4" 1.296.24 1,294.08 5 30-35 1,264.08-1,259.08 37.66 60.5

2A North 2 1,302.46 1,300.51 5 15-20 1,285.51-1,280.51 21.88 23 2B Central 4 1,302.31 1,300.60 4 31-35 1,269.60-1,265.60 36.52 35 2C South 1,302.22 1,300.66 5 48-53 1,252.66-1,247.66 54.25 56

3A South 1,304.27 1,301.31 5 17.8-22.8 1,283.51-1,278.51 25.88 23.5 3B North 1,303.10 1,301.19 5 30-35 1,271.19-1,266.19 36.91 39

4A Southwest 1,296.51 1,294.48 5 10-15 1,284.48-1,279.48 16.92 15 4B South Southeast 1,2%.21 1,294.42 4 31.5-35.5 1,262.92-1,257.92 36.51 35 4C North 1,296.91 1,294.78 4 42-46 1,252.78-1,248.78 47.68 61

5A North 1,289.98 1,287.80 5 4.5-9.5 1,283.30-1,278.30 11.21 9.5 SB South 1,290.03 1,287.86 4 31-35 1,256.86-1,251.86 35.90 35

6A Central 1,297.49 1,295.60 5 12-17 1,283.60-1,278.60 18.65 17 68 East 1,297.52 1,295.58 4 31-35 1,264.58-1,259.58 36.53 35 6C West 1,297.99 1,295.66 4 46-50 1,249.66-1,245.66 52.23 50

7A Single 1,290.24 1,287.88 5 7-12 1,280.88-1,275.88 14.48 12.5 7B Abandoned 35 _ _ 8 Boring only 1,310.0 Est. . 43 1,305.5 - - 25 8A Boring only -

S1ng1e 1,305.25 1,303.93 19.4-24.4 1,284.53-1,279.53 24.5

10 Single 1,304.19 1,302.76 16-21 1,286.76-1,281.76 21.00 26 TABLE 4-1 LONG PRAIRIE WELL DATA (Continued) -v.

11 Single 4 1,299.54 1,297.45 5 50-55 1,247.45-1,242.45 56.65 62.9

12 Boring only - 1,303.5 Est. - 13.5

13 Single 4 1,295.68 1,293.82 5 50-55 1,243.82-1,238.82 56.95 65.5 .u , 14B North 2 1,297.95 1,296.13 5 21-26 1,275.13-1,270.13 27.95 1 4C South 4 1,297.83 1,295.99 5 50-55 1,245.99-1,240.99 56.45 61 01

BAL-2B Single 2 1,304.98 1,302.84 8 57-65 1,294.84-1,286.84 80 BAL-2C Single 2 1,297.02 1,294.93 10 40-50 1,254.93-1,244.93 59

Municipal Wells

HW3 - Top of Pipe 1,320.78 Floor 1,318.31 w/3 Blank MW4 - Top of Pipe 1,297.48 21 34-45 55 Floor 1,295.45 48-55

MW5 - Top of Pipe 1,298.26 15 41-56 63 Floor 1,295.96

MW6 - Top of Pipe 1,305.81 23 53.1-76.2 140 Floor 1,303.81 4.2 Site Specific Hydrogeology 4.2.1 Groundwater Table Elevations Groundwater elevations were measured several times during conduct of the remedial investigation. Data from these measurements given in Table 4-2 and was used to prepare groundwater altitude maps for November 27 and December 22, 1986 and January 12, 1987. These appear as Figures 4-5, 4-6, and 4-7 respectively. The groundwater altitude maps show that flow is to be north-northeast. 4.2.2 Hydrogeoloqic Evaluation The section of the Long Prairie River located within the City of Long Prairie is underlain by highly permeable sands and gravel which forms the aquifer that supplies groundwater to the city. The aquifer's extent is limited by low permeability glacial tills which form the uplands to the river valley. As seen on the USGS topographic map, Long Prairie, Minnesota, the river flow is diminished considerably when it enters the Long Prairie sand plain. This is due to the increased infiltration of river water into the more permeable sands and gravel. The aquifer is predominantly under water table conditions with scattered clay lenses which act as local confining units. Such clay lenses exist in the vicinity of municipal wells 4 and 5 and monitoring wells 4, 13, and 14 (see Sections A-A1 and C-C', Figures 4-2 and 4-3). Groundwater flow in the Long Prairie sand plain aquifer is controlled by recharge and discharge relationships between the Long Prairie River and aquifer which is in turn controlled by seasonal precipitation patterns. Groundwater pumping also has a local control over groundwater movement and generally groundwater flows towards the north-northeast within the study area.

REPT4/tdg 4-6 TABLE 4-2

GROUND WATER ALTITUDES* LONG PRAIRIE. MINNESOTA

M) (2) (3) (3) ,(2) Well No. 11/25/86 12/22/86 ' 1/12/87 4-2-87 2/9+1 0/«

1a 1286.64 1286.45 1286.38 1286.52 1286.31 1b 1286.66 1286.46 1286.37 1286.67 1286.27

2a 1286.27 1285.94 1285.91 1286.02 1286.01 2b 1286.26 1285.91 1285.93 1286.03 1285.84 2c 1286.27 1285.95 1285.94 1286.05 1285.88

3a 1286.27 1285.99 1285.90 1286.12 1286.97 3b 1286.25 1286.16 1285.90 1286.10 1285.00

4a 1285.87 1285.55 1285.43 1285.35 1285.88 4b 1285.87 1285.55 1285.44 1285.32 1285.32 4c 1285.86 1285.56 1285.45 1285.36 1285.30

5a 1285.40 1285.19 1285.66 1285.07 1285.06 5b 1285.39 1285.24 1285.15 1285.07 1285.17

6a 1286.00 1285.74 1285.63 1285.79 1285.79 66 1286.00 1285.71 1285.63 1285.65 1285.62 6c 1285.99 1285.75 1285.62 1286.65 1285.52

7a 1285.84 1285.58 1285.50 1285.53 ICED UP

9 1285.56 1285.17 1284.87 1284.47 1284.67

10 1288.19 1288.00 1287.94 1289.93 1288.11

11 1285.72 1285.31 1285.20 1284.85 1285.08

13 1285.68 1285.37 1285.32 1285.21 1285.18

14b 1285.76 1285.58 1285.33 1285.12 1285.45 14c 1285.81 1285.44 1285.35 1285.12 1285.24

BAL-2B 1285.49 1282.42 1281.88 1262.43

BAL-2C 1285.37 1284.92 1284.93 1284.82

^Altitudes in feet above KSL.

Notes;

1. Measurements taken by Malcolm Plrnie, Inc. 2. Measurements taken by PACE Laboratories, Inc. 3. Measurements taken by MPCA.

REPT4/tdg - 7 •--. -fI .- is!=- • "-jU- : « ! .^, Lr

SCALE: 1't «2S* 1288.46 QROUNOWATER ALTITUDE

DIRECTION OF GROUNDWATER FLOW November 27. 1986 LONQ PRAIRIE REMEDIAL MALCOLM •'•Nil HC MA1OXJM INVESTIGATION REPORT PIRfsilE GROUNDWATER ALTITUDE FIGURE 4-5 CONTOUR MAP SAL-?:; • . XV = WW6

;

«; f

SCALE: 1286.45 GROUNOWAT6R ALTITUDE

DIRECTION OF GROUNDWATER FLOW December 22, 1986 LONG PRAIRIE REMEDIAL MALCOLM INVESTIGATION REPORT PIRNIE GROUNDWATER ALTITUDE FIGURE 4-5 CONTOUR MAP X/ I

-.' -,'•-, .'• ic

•»-(Cc". CT7«I

SCALE: l"s 625' 1286.45 GROUNOWATER ALTITUDE DIRECTION OF GROUNDWATER FLOW January 12, 1987 LONG PRAIRIE REMEDIAL >l*Mlt. NC MAUCOUVt INVESTIGATION REPORT PIRNIE GROUNDWATER ALTITUDE FIGURE 4-7 CONTOUR MAP 4.2.3 Aquifer Tests As part of the remedial investigation, a pumping test was proposed to determine the transmissivity and storage coefficient of the aquifer. Transmissivity is the ability of an aquifer to transmit water through its medium while storage coefficient refers to the volume of water stored in a unit volume of the aquifer. Determination of these parameters allows for comparison of widely varying geologic formations with respect to their capability to function as an aquifer. A 72 hour pumping test was conducted at municipal well no. 4 from March 12 - March 16, 1987. Municipal well no. 5 and monitoring well nos. 4A, 4B, 4C, 13C, 14B, and 14C were used as observation wells. Stevens Type F Recorders were installed on wells 4C, 13, 14C and 4B to continually monitor water levels. Water levels were measured on March 12, 1987 and again on March 13, 1987 prior to start of the pumping test in order to establish a short term trend in groundwater levels. No change in water levels were observed. The pumping test was started at 9:50 am, March 13, 1987, at a rate of 222 gallons per minute (gpm). The pumping rate was measured by an instantaneous discharge readout and checked by two cumulative discharge gauges. No variation in discharge rate was observed throughout the test. Water was discharged to the street and drained into a storm sewer. Pumping was stopped at 10:00 am, March 16, 1987. Water level recovery measurements were made until 1:00 pm, March 16, 1987, at which point there was greater than 95 percent recovery. Pumping test data analysis is based on the Theis non- equilibrium formula and modification thereof. The Theis formula is based on the following assumptions: 1. The water bearing formation is uniform in character and permeability in both vertical and horizontal directions. 2. The formation has uniform thickness. 3. The formation has infinite areal extent. 4. The formation receives no recharge from any source.

REPT4/tdg 4-8 5. The pumped well penetrates and receives water from the full thickness of the waterbearing formation.

6. All the water is removed from storage and is discharged instantaneously with lowering of the head. 7. The pumping well is 100 percent efficient. 8. The water table has no slope. Few, if any, aquifers conform to all these assumptions but application of the Theis formula and its variations provides acceptable values of transmissivity and storage coefficient to otherwise unsolvable mathematical equations for use in aquifer comparison. The Long Prairie pumping test data was analyzed by the Jacob Straight Line Approximation and Boulton's Method for aquifer tests under water-table conditions. Results are tabulated in Table 4-3. The values of transmissivity obtained show an excellent aquifer capable of transmitting large amounts of water. All values correspond well with each other and are in agreement with characteristics of the coarse and very coarse sand noted in the geologic log of monitoring well No. 13 and published tables relating transmissivity, hydraulic conductivity and formation materials. The high values of transmissivity are supported by the near instantaneous response recorded in the monitoring wells equipped with continuous recorders. The wetlands located west of the pumping well serve as a positive boundary, supplying water to the municipal well and preventing accurate analysis of true transmissivity late in the pumping test. The calculated storage coefficient represents an acceptable value for water table aquifers. The data obtained during the pumping test was tabulated (see Appendix C), and plotted on log/log graph paper (see Appendix D). The pumping test plots are a graphic representation of the pumping test. They show drawdown of water levels in the pumping well and observation well with respect to time. The data which was used in preparing the

REPT4/tdg 4-9 TABLE 4-3

AQUIFER TEST RESULTS

WELL TRANSMISSIVITY

Municipal Well 4 5.0 x 105 ft3/ft/day

Municipal Well 5 5.97 x 106 ft3/ft/day

Municipal Well 5 1.78 x 107 ft3/ft/day Jacob Straight Line

Municipal Well 5 and Monitoring Wells 13c, 14c, 4b, 4c 5.35 x 105 ft3/ft/day Jacob Straight Line

WELL STORAGE COEFFICIENT

Municipal Well 5 .307

REPT4/tdg 4-10 semi-log plots for municipal well 4 and municipal well 5 was plotted in the field during the pumping test. The aquifer pump test results which appear in Table 4-3 were used in the development and calibration of computer modeling techniques described in section 4.3.3.1.

4.3 Groundwater Quality 4.3.1 Groundwater Monitoring Programs As discussed before, groundwater contamination was first detected in Long Prairie in August, 1983 when the Minnesota Department of Health (MDH) detected chlorinated ethylene compounds in two of the city's five municipal potable wells. The presence of those contaminants in Municipal Wells 4 and 5 was confirmed in a second sampling survey conducted by MDH in October, 1983. Later in the same month, the Minnesota Pollution Control Agency (MPCA) collected water samples from 21 private potable wells in Long Prairie. Analyses showed 9 of those wells were contaminated with compounds similar to those found in the two contaminated municipal wells. Additional sampling surveys of the municipal and private wells were conducted in November, 1983, January, February, March, April, June, and October, 1984 prior to commencement of the Remedial Investigation by Malcolm Pirnie, Inc. in October, 1986. Analytical results of the MDH and MPCA sampling surveys are given in Tables 4-4 (Municipal Wells) and 4-5 (Private Wells). Table 4-6 identifies the owners and addresses of the private wells sampled. Figure 4.8 shows the location of the private and municipal wells sampled in Long Prairie. In February 1984, 17 monitoring wells were installed by MPCA in the Northeastern quadrant of the city to monitor groundwater quality. These monitoring wells were sampled in the same month. Construction details of those wells are given in Table 4-7; and their locations are shown in Figure 4-8. Analytical results from the February, 1984 sampling survey are given in Table 4-8. All analyses performed up until the

REPT4/tdg 4-11 TABLE 4-4 Chlorinated Ettylene Concentrations (ug/D fcjnldpal Wtll K>n1tor1ng Oatl long Prairie, Minnesota August 1983 - September 1984 ds-1. 2- 1,1.2- 1.1.2.2- Sun of Oichloro- TMchloro- Tetrachloro- Chlorinated Wen » Date of Sample ethylene ethylene ethylene Ethyl enes 1 8-2543 U443 12-2743 2-944 < 2 8-25-83 114-83 12-2743 « 2-944 4-1644 3 8-2543 11443 P* P 12-2743 2-944 4-1644 4 8-2543 0.60 0.60 17.0 18.2 10-1243 0.80 1.0 26.0 27.8 10-2443 2.4 1.6 40.0 44.0 11443 7.8 5.9 110.0 123.7 2-944 5.7 4.2 83.0 92.9 4-1644 1.7 7.8 130 139.5 6-1144 7.7 5.3 110 123 5 8-2543 17.0 9.3 280 306.3 10-1243 16.0 11.0 270 297 10-2443 12.0 8.6 260 280.6 11443 6.4 7.0 150 163.4 2-944 10.0 10.0 230 250 4-1644 12.0 10.0 130 152 6-1144 14.0 10.0 140 164 10-344 12.0 11.0 100 123 6 11443 6444** Iron- 10-1243 0.70 0.70 24.0 25.4 Filter 10-2443 0.70 0.50 13.0 14.2 Effluent* 11443 U-2743

Carbon 6444 Filter 6-1144 Effluent 7-544 -#4 7-2344 8-1544 9-2044 Carbon 6444 < Filter 6-1144 < Effluent 7-544 < -*5 7-2344 < 8-1544 .30 < o."30 9-2044 .30 < 0.30 * Well 15 was reamed fro» service taoedlately following the 10-1243 Veil 14 MBS reoDved froa service tanedlately following the 10-2443 Well *3 fed the iron-filter plant after 10-2443 ** M sets of stales were collected through the day P Present in Samples at Concentrations below the method detection limit. 4-12 TABLE 4-5

cis-1,2- 1,1,2- 1,1,2,2- Sum of Dichloro- Tn'chloro- Tetrachloro- Chlorinate' CODE NO. Date of Samole ethylene ethylene ethylene Ethylenes 41 10/26/83 < < < < 42 2/8/84 < < < < 46 10/20/83 0.2 0.9 11.0 12.1 7/20/84 0.2 0.7 8.0 8.9 47 11/8/83 < < < 1.5 49 10/26/83 < < < < 1/4/84 < < < < 7/20/84 < < < < 51 11/8/83 62.0 34.0 920.0 1016.0 54 11/8/83 < 0.2 8.0 8.2 56 2/8/84 25.0 17.0 510.0 552.0 57 4/26/85 24.0 23.0 42.0 89 58 10/26/83 < < < < 1/4/84 < < < < 7/20/84 < < < < 59 11/8/83 < < 2.0 2.0 1/4/84 < < < < 7/20/84 < < < < 61 11/8/83 < < < < 7/20/84 < < < < 62 3/2/84 44.0 24.0 1000 1068.0 63 3/2/84 47.0 38.0 730 815.0 65 2/8/84 < 0.4 14.0 14.4 66 11/8/83 < 0.2 11.0 11.2 4/26/85 < < 6.6 6.6 68 10/26/83 24.0 11.0 510.0 545.0 2/8/84 20.0 11.0 500.0 531.0 69 11/8/83 < < < 1.7 (dichlor ethane)

4-13 TABLE 4-5 (CONTINUED) ds-1,2- 1.1,2- 1,1,2,2- Sum of Dichloro- Tn'chloro- Tetrachloro- Chlorinatec CODE NO. Date of Sample ethylene ethylene ethylene Ethylenes 72 11/8/83 < < < < 74 10/26/83 0.2 0.5 2.0 2.7 1/4/84 0.8 2.0 4.0 6.8 7/20/84 0.5 2.3 13.0 15.8 75 10/26/83 < < < < 80 10/26/83 < < < < 82 10/26/83 0.2 0.8 2.0 3.0 83 10/26/83 < < < < 84 2/8/84 18.0 10.0 500.0 528.0 85 10/26/83 < < < < 7/20/84 < < < < 87 2/8/84 1.6 1.9 33.0 36.5 88 10/26/83 0.4 1.0 230 231.4 4/26/85 < < < < 89 10/3/84 < < < < 92 10/26/83 < < < < 173 11/8/83 < < < < 223 11/8/83 < < < < 500 • 10/3/84 3.0 1.5 23.0 27.5

4-14 TABLE 4-6 LONG PRAIRIE MINNESOTA

DOMESTIC WELL OWNERS IN LONG PRAIRIE, MINNESOTA

CODE NO. NAME ADDRESS 1 Albert Anderson 432 6th St. NE 2 Gerald Anderson 420 6th St. NE 3 Melvin Anderson 225 1st. Ave. No. 4 Evered Bard 221 6th St. NE. 5 Harold Barker 121 No. 1st. St. 6 Charles Bense 409 3rd Ave. No. 8 Anna Berndt 620 2nd Ave. NE. 9 Frank Bertzyk 216 6th St. NE. 10 Blais Body Shop 114 Central Ave. 11 Gary Zastrow-owner 520 2nd Ave. NE 12 Anthony Borgheinck 815 2nd Ave. NE 13 Kilmer Brastad 225 6th St. NE 14 Lloyd Burger 423 6th St. NE 16 Erna Cizek 620 4th Sve. NE 17 Walt Colby 217 Todd St. No. 19 Everett Dailey 223 7th St. NE. 20 Ray Dirschel 421 2nd Ave. No. 21 John Dudek 410 2nd Ave. No. 22 Loren Eckel 424 3rd Ave. No. 23 Rudy Norlinger 711 2nd Ave. NE. 24 Gladys Ellwanger 622 3rd Ave. NE 25 Leonard Emblom 823 2nd Ave. NE 26 Roger Enns 424 6th St. NE 27 Fern Erickson 430 3rd Ave. No. 28 Dwayne Finch 306 6th St. NE. 29 Randy Gorr 428 6th St. NE 30 Agnes Gossell 215 6th St. NE 31 Enuna Grauman 324 2nd Ave. No. 32 Mrs. Geo. Grecula 210 4th St. No. 33 James Gripne 15 3rd St. No. 34 Emil Hanneman 324 3rd Ave. No. 35 Otto Hanneman 724 1st. Ave. NE 38 . Lorraine Hedin 620 3rd Ave. No. 39 Richard Hokanson 116 6th St. NE. 40 Romaine Irsfeld 220 6th St. NE 41 Bruce Johnson 618 7th St. NE 42 Harold Johnson 414 6th St. NE 43 Lawrence Keller 436 6th St. NE 44 Elaine Koester Rt. 1, Brainerd 45 Mrs. Albert Koester 421 3rd Ave. No. 46 Bert Lambrecht 410 3rd Ave. No. 47 Frank Lano 109 1st. St. No. 48 August Lentz 425 7th St. NE.

4-15 TABLE 4-6 (CONTINUED)

CODE NO, NAME ADDRESS 49 Anthony Lisson, Jr. 421 St. Ave. No. 50 Long Prairie Auction Long Prairie, MN 51 Elizabeth Luedeke 120 4th St. No. 52 Carl Martenson 613 2nd Ave. NE. 53 Tom McQuire 125 Todd St. No. 54 John Michels 221 4th St. No. 55 Walter Miller 211 4th St. No. 56 Josephine Minke 424 2nd Ave. NE. 57 Robbin Minke 415 3rd Ave. No. 58 Berthold Mueller 314 6th St. NE. 59 Jeanette Neidhart 321 3rd Ave. No. 60 Robert Nelson 225 3rd St. No. 61 Al Fierce1 405 6th St. NE. 62 Getrude Pederson 427 2nd Ave. No. 65 Ainslee Peterson 514 2nd Ave. NE. 66 Lowell Peterson 511 2nd Ave. NE. 67 Percy Peterson 624 7th St. NE. 68 Allan Priebe 515 3rd Ave. NE. 69 Maurice Pugh 30 2nd Ave. No. 70 Kenneth Rausch 212 6th St. NE. 71 Oliver Burg 215 4th St. No. 72 Bud Roman 26 4th St. No. 73 Johnny Saarela 621 2nd Ave. NE. 74 Harland Sargeant 110 3rd St. No. 75 Leo Schahn 224 6th St. NE. 76 Leonard Schintgen 610 2nd Ave. NE. 77 Don Schmidt 39 Riverside Dr. 78 Adrian Schomaker 120 Todd St. So. 79 Adolph Schroeder 120 6th St. NE. 80 Larry Schroeder 610 5th Ave NE. 81 Jeanette Schultz 630 4th Ave NE. 82 Hirera Severson 318 3rd Ave No. 83 Fred Starry 602 6th St. NE. 85 David Venekamp 513 7th St. NE. 89 Tim Willey 419 6th St. NE. 90 Grace Winkelman 715 2nd Ave NE. 91 Elsie Witsoe 415 2nd Ave No. 92 Larry Rieber 404 6th St. NE. 93 Janet Adams 435 1st. St SO. 94 Randy Alsleben 212 4th St. SO. 95 David Anderson 310 4th Ave SW. 96 Laura Anderson 455 Todd St. So. 97 Peggy Anderson 521 2nd Ave. SW. 98 Dennis Angell 115 4th Ave. SW

4-16 TABLE 4-6 (CONTINUED)

CODE NO. NAME ADDRESS 99 Alice Arco 331 1st. St. SW. 100 Richard Barhorst 220 4th Ave. SW. 101 Allen Bauer 434 Lake St. SO. 102 Jim Becker 419 3rd Ave. SW. 103 Elmer Bengston 410 4th St. SO. 104 Melvin Bense 420 3rd Ave. SW. 105 Marin Bertzyk 529 Lake St. So. 106 Gerald Biermaier 25 2nd Ave. SW. 107 Susan Bills 306 1st. St. SW. 108 Olga Blais 420 1st. St. SO. 109 Carol Blake 425 1st. St. SO. 110 Joe Bleess 513 4th Ave. SW. 111 Norman Bodle 408 Lake St. SO. 112 Eugene Boisvert 510 4th Ave. SW. 113 Roger Bokinski 540 1st. St. SO. 114 Dennis Bollin 109 2nd Ave. SW. 115 Mrs. R. J. Borgert 305 1st. St. SW 116 Robert Boyer 325 1st. St. SW. 117 Ralph Browen 309 2nd Ave. SW. 118 Chester Bruce 438 Todd St. SO. 119 Henrietta Bruder 525 Lake St. SO. 120 Tom Carlson 329 1st. St. SW. 121 Norman Chase 429 Todd St. SO. 122 Mel Chelman 503 3rd Ave. SW. 123 Louis Cizek 524 1st. St. SO. 124 Joe Claseman 427 Lake St. 125 Grace Claseman 313 2nd Ave. SW. 126 Vic Claseman 210 4th Ave. SW. 127 Florian Colling 116 2nd Ave. SW. 128 Ray Cowdery 510 1st. St. So. 129 Ellsworth Duncanson 607 5th Ave. NE. 130 Vic Doese 129 2nd Ave. SW. 131 Rosetta Drevlow 28 3rd Ave. SW 132 Mrs. Geo. Duel 445 Todd St. SO. 133 Curt Earhart 212 2nd Ave. SW. 134 Al Ebner 402 1st. St. SO. 135 Norman Eckes 440 Lake St. SO. 136 Andrew Eggert 32 3rd Ave. SW. 137 Alan Erickson 517 1st. St. SO 138 Stephan Fraune 425 Todd St. SO. 139 Ed Geinsenhof 14 2nd Ave. SW. 140 Ernest Gillespie 425 4th Ave. SW. 141 Arnold Goertz 424 Todd St. So. 142 Kenneth Gothman 330 1st SW 143 Phillip Gothman 324 1st. St. SW 144 John Granlund 448 Lake St. So.

4-17 TABLE 4-6 (CONTINUED)

CODE NO. NAME ADDRESS 145 George Gustafson 437 Todd St. SW 146 Gary Hammer 310 3rd Ave. SW 147 Gil Barren 214 1st. Ave. No. 148 Isadore Hayda 529 1st. St. So. 149 Don Hedin Highway 71 So. 150 Hedin Realty Long Prairie 151 Wallace Hedlund 240 4th St. So. 152 Fredric Hein, Sr. 125 2nd Ave. SW. 153 Mike Herding 320 3rd Ave. SW 154 Harold Hessedahl 315 3rd Ave. SW 155 Mrs. J.E. Hetherington 521 1st. St. So. 156 James Hetland 441 Todd St. So. 157 Dave Heiserich Cloquet, Mn. 55720 158 Bernard Hillmer 305 4th St. SW. 159 Steven Hinrichs 120 2nd Ave. SW 160 Dale Hockemeyer 216 2nd Ave. SW 161 Ray Hoeschen 319 3rd St. SW 162 Phillip Hollerman 464 Todd St. So. 163 Allen Host 208 4th St. So. 164 Gail Hubbard 433 1st. St. So. 165 Herman Irsfeld 546 Lake St. So. 166 Roger Johnson 225 2nd Ave. SW. 167 Mrs. Rodene Jones 420 2nd Ave. SW. 168 Don Kamphenkel 505 1st. St. So. 169 August Karsten 308 2nd Ave. SW 170 Emma Karsten 312 2nd Ave. SW. 171 James Kingston 215 3rd Ave. SW. 172 Lawrence Kircher 311 3rd Ave. SW 173 Mrs. Ernestine Knaak 14 3rd Ave. So. 174 Joseph Kruzel 556 Lake St. So. 175- Mrs. Otto Kuchenbecker 408 3rd Ave. SW. 176 Frank Kunerth 519 4th Ave. SW 177 Walt Kunerth 113 2nd Ave. SW 178 Susan Lang 119 3rd Ave. No. 179 Mabel Lawler 526 Lake St. So. 180 Alice Leagjeld 15 5th Ave. So. 181 Joe Leagjeld 315 1st. St. SW 182 Victor Lemke, Sr. 305 2nd St. SW 183 Vic Lemke, Jr. 112 3rd Ave. SW 184 Dave Leagjeld-owner Long Prairie, MN. 184 Lillie Lowe 221 2nd St. SW 185 Mrs. Lyle Lunceford 124 2nd Ave. SW 185 Louis Letoruneau 415 1st. St. So. 186 Kenneth Lindstrom 220 4th St. So. 186 Miles Maland 509 4th Ave. SW. 187 Art Marske 451 Todd St. So.

4-18 TABLE 4-6 (CONTINUED)

CODE NO. NAME ADDRESS 188 Charles McMurray 550 Lake St. So. 189 Frank McQuiod 209 4th Ave. SW. 190 Tom Mead 213 4th Ave. SW. 191 Clifford Meier 424 2nd Ave. SW 192 Nick Meier 520 Lake St. So. 193 Gerald Meis 209 3rd Ave. SW 194 Armin Meyer 516 1st. St. So. 195 Mark Misksche 415 4th Ave. SW. 196 Emily Miller 521 Lake St. So. 197 Wayne Minke 415 3rd Ave. No. 198 Blanche Moe 414 4th Ave. SW. 199 Lawrence Motl 404 4th Ave. SE 200 Douglas Moulton 419 2nd Ave. SW 201 Gene Mueller 506 1st. St. So. 202 Bertha Muenzhuber 414 4th St. So. 203 Mildred Murphy 221 2nd Ave. SW. 204 Bucky Naumann 321 1st. St. SW. 205 Duane Noble 215 2nd Ave. SW. 206 Floyd Noble 305 4th Ave. SW. 207 Greg Ostroski 456 Todd St. So. 208 Maurice Park 38 Riverside Dr. 209 Louis Perish 320 3rd St. SW 210 Joe Pesta 412 4th Ave. SW. 211 Arthur Peterson 112 2nd Ave. SW 212 Occupant 414 1st. St. So. 213 George Peterson 227 Todd St. So. 214 Marvin Peterson 236 4th St. SE. 214 Myron Petrie 423 So. Lake St. 215 Lydia Petrie 320 2nd Ave. SW 216 Hildegard Poegel 423 3rd Ave. SW 217 Leo Putzkey 310 4th St. SW 218 Tom Quinn Rt. 1, Osakis,56360 219 Paul Rachey 211 2nd Ave. SW 220 Melvin Rahn 415 3rd Ave. SW 221 Norma Ranzenberger 450 Todd St. So. 222 Daniel Rasmussen 454 Lake St. So. 223 Darwin Rice 114 2nd Ave. So. 224 Mrs. Richard Robinson 414 3rd Ave. SW 225 Mrs. A. E. Roman 316 2nd Ave. SW 226 Dennis Rosenow 437 1st. St. So. 227 Joyce Rosenow 106 3rd Ave. SW 228 Mrs. Wayne Rowe 412 Lake St. So. 229 Herman Sadlovsky 324 2nd Ave. SW 230 Michael Sandgren 309 1st. St. SW

4-19 TABLE 4-6 (CONTINUED)

CODE NO NAME ADDRESS 231 Bradford Sax 206 2nd Ave. SW 232 Ray Schabel 24 3rd Ave. SW 233 Gregory Schaubhut 225 4th Ave. SW 234 Amanda Schmidt 433 Todd St. So. 235 Doug Schmidt 311 3rd Ave. SW 236 Herman Schmidt 406 1st, St. So. 237 Ralph Schmidtknecht 312 1st. St. SW 238 Ray Schultz 15 6th St. NE 239 Bruce Sebek 445 1st. St. So. 240 Lee Simpson 449 1st. St. So. 241 Jerome Stans 405 Todd St. So. 242 Mrs. Frank Starry 216 3rd St. SW 243 Frank Steffen 509 Lake Street 244 Milly Steinberg 409 4th Ave. SW 245 Walter Steinert 315 4th Ave. SW 246 Mrs. Arvid Sternquist 530 1st. St. So. 247 Albert Steuck 430 1st. St. So. 248 Karen Steuck 428 Lake St. So. 249 Harold Stevens 410 4th Ave SW 250 Robert Strom 427 4th Ave. SW 251 Allen Sundberg 321 2nd Ave. SW 252 Vera Swedal 409 Todd St. So. 253 Adolph Tabatt 323 4th Ave. SW 254 Kenneth Thull Long Prairie, MN. 255 Calvin Torgerson 231 Todd St. So. 256 Bruce Triebenbach 608 1st. St. So. 257 Mrs. Ed. Triebenbach 536 Lake St. So. 258 Donald Truog 509 1st. St. So. 259 Darrell Tuckenhagen 307 3rd Ave. SW 260 Robert Tuomala 204 4th St. So. 261 Mareella Van Heel 318 4th Ave. SW 262 Ronald C. Werner 115 3rd Ave. SW 263 Arnold Westerberg 315 5th Ave. SW 264 Ceclia Westerberg 319 4th AVe. SW 265 Ray Wickum 410 1st. St. So. 266 Peter Weiland 416 2nd Ave. SW 267 Tom Wolf 518 4th Ave. SW 268 Robert Wolter 419 1st. St. So. 269 John Wysocki 407 2nd Ave. SW 270 Todd Co. State Bank Highway 71 South 271 John's Parts Supply Highway 71 South

Note: 1. Water quality results in Table 1.4 are keyed to this list, 2. The location of these wells are illustrated on Plate 1.1.

4-20 TABLE 4-7 LONG PRAIRIE, MINNESOTA

MONITOR WELL CONSTRUCTION DETAILS

SCREEN SETTING WELL DIAMETER MEASURING LOCATION NO. (INCHES) POINT . , DEPTH IN FEET 21 ELEVATION1'' ELEVATION i' TOP BOTTOM TOP BOTTOM la 2 1295.40 9.5 - 14.5 1283.40 - 1278.40 1st Ave.fi 2nd St. (city lot) 2a 2 1301.21 15 20 1284.15 - 1279.15 1st Ave.i 3rd St. 2b 4 1301.11 31 35 1268.11 - 1264.11 (liquor store)

3a 2 1303.01 17.8 - 22.8 1282.31 - 1277.31 Post Office (along alley)

4a 2 1295.08 10 15 1283.03 - 1278.03 3rd Ave.4 Todd St. 4b 4 1294.80 31.5 - 35.5 1261.30 - 1257.30 (ball field) 4c 4 1295.50 42 46 1252.50 - 1247.50

2 1288.69 4.5 - 9.5 1281.89 - 1276.89 old city dump site 30 4 1288.81 31 35 1255.81 - 1253.81

6a 2 1296.33 12 17 1282.23 - 1277.23 4th St. 4 2nd Ave. 6b 4 1296.39 31 35 1263.39 - 1261.39 left/west side 6c 4 1296.86 46 50 1248.86 - 1244.86 right/east side 7a 2 1288.96 7 12 1279.36 - 1274.36 Hockey Rink 7b 4 1288.63 31 35 1255.63 - 1253.63

9a 2 1305.52 19.4 - 24.4 1284.44 - 1279.44 632 ft. S. of Co. Rd. 27 BAL-2b 2 1305.25 57 65 1246.25 - 1240.25 N side of M.wellj*6 BAL-2c 2 1297.14 40 50 1255.14 - 1245.14 in fld.200'W of cemetery/fairgrounds

I/Feet above mean sea level. 21Depth in feet below ground level.

4-21 TABLE 4-8 NORTHERN LONG PRAIRIE - MONITORING WELL ANALYSES February, 1984

cis-1,2- 1.1.2- 1.1.2,2- Sum of Dlchloro- Trichloro- Tetrachloro- Chlorinated Monitoring Well t Date of Sarnie ethylene ethylene ethylene Ethylenes

la 2/17/84 (Serco) 0.2 < 2.1 2.3

2a 2/17/84 (Serco) 8.3 5.1 160 173.4 2b 2/10/84 (Serco) 36 23 1200 1259 2/10/84 (MDH) 48 33 520 601

3a 2/17/84 { Serco) < < 2.0 2.0

4a 2/16/84 (Serco) 34 15 1100 1149 4b 2/10/84 (Serco) 16 8.8 210 234.8 2/10/84 (MDH) 10 8.2 110 128.2 4c 2AO/84 (Serco) 6.0 1.5 20 27.5 2/10/84 (MDH) S.8 2.6 22 30.4

5a 2/13/84 (Serco) 2.7 2.6 < 5.3 2/13/84 (MDH) 2.4 0.2 < 2.6 5b 2/14/84 (Serco) < 4.4 7.6 12.0 2/13/84 (MDH) 0.2 1.9 4.0 6.1

6a 2/17/84 (Serco) 37 29 520 586 6b 2/14/84 Serco) SO 36 1200 1286 2/14/84 (MDH) SO 45 750 845 6c 2/13/84 (Serco) 9.5 18 330 357.5 2/13/84 (MDH) 8.2 17 160 185.2

7a 2/17/84 (Serco) < < < < 7b 2/14/84 (S«rco) < < < < 2/14/84 (MDH) < < < <

9a 2/14/84 < 1.6 < 1.6

4-22 i . ___vX^£C/; ^r- — ;> LONG PRAIRIE, MINNESOTA ; —— ^=^ r>/ .f r U WELL LOCATION MAP" n f 5

• EXISTING MONITOR WELL LOCATIONS

O TEST BORINGS

0 MUNICIPAL WELLS

G ( TJ'*

G ) n

u -i;: 7147 ! 0 n a FK3URE 4-8 o February/ 1984 survey was MDH Method 465B. This procedure determines concentrations of the 53 volatile organics listed in Table 4-9. As one of the first tasks of the Remedial Investigation, a first round of samples was collected from the 17 existing monitoring wells, municipal wells 3, 4,5 and 6 and nine selected residential wells on October 13 and 14, 1986. Analytical results of this round are labelled "Round 1" in Table 4-10. Following a review of the first round of data, it was determined that the location of new monitoring wells proposed by Malcolm Pirnie in the July, 1986 Work Plan were still appropriate given the contan. Levels detected. In November, 1986 eight new monitoring wells (MW-1B, 2C, 3B, 10, 11, 13C, 14B, and 14C) were installed. These l:>:i-.*^ .^t shown on Figure 4-9. Following well installation, a second round of sampling was conducted on December 22 and 23, 1986 in which the new wells were sampled along with MW-6C, BAL-2B and Municipal Well 6. Analytical results of this round are labelled as Round 2 and are given in Table 4-10. A final or third round of sampling was conducted on February 9, and 10, 1987 in which all monitoring wells (previously existing and new, except MW-7B which was abandoned in November, 1986) and municipal wells 3,4,5 and 6. Analytical results of the final round are labelled as Round 3 and are also given in Table 4-10. 4.3.2 Groundwater Analyses 4.3.2.1 Municipal Wells - Municipal wells 3 and 5 were sampled once during Round 1; municipal well 4 was sampled once during Round 1 and six times as part of the hydrogeologic investigation; and municipal well 6 was sampled during each of Rounds 1, 2, and 3. Analytical results are given in Table 4-11. Municipal wells 1 and 2 were not sampled during this remedial investigation since previous analyses by MPCA did not show contamination and they are not hydrogeologically connected to the area of known groundwater contamination.

REPT4/tdg 4-23 TABLE 4-9 MINNESOTA DEPARTMENT OF HEALTH METHOD 465B ANALYTES

PARAMETER STO^ET NUMBER CAS HUM6E-*

BRUMOOICHLOROMETHANE 32101 75-27-4 DICHLOROACETONITRILE 3018-12-0 2,3-DICHLORO-l-PROPENE 78-83-6 1,2-DICHLOROPROPANE 34541 7H-87-5 1,1-DICHLOKO-l-PROPENE 563-58-6 Ci S-l,3-DICHLORO-l-PRUPENE 34699 10061-02-6 1,1,2-TRICHLOROETHYLENE 39180 79-01-6 1,3-DICHLORUPKOPANE 142-28-9 CHLORODIBROMOMETHANE 32105 124-48-1 1,1,2-TRICHLOROETHANE 34511 79-00-5 Trans-1,3-DICHLORO-l-PROPENE 10061-01-5 1,2-DIBROMOETHANE 106-93-5 2-CHLOROETHYLVINYL ETHER 34576 100-75-8 BROMOFORM 32104 75-25-2 1,1,1,2-TETRACHLOROETHANE 630-20-6 1,2,3-TRICHLOROPRUPANE 96-18-4 1,1,2,2-TETRACHLOROETHANE 34516 7y-34-5 1,1,2,2-TETRACHLORCETHYLENE 127-18-4 PENTACHLOROETHANE 76-01-7 CHLOROBENZENE 34301 108-90-7 ACETONE 67-64-1 TETRAHYDRUFURAN 109-99-9 METHYL ETHYL KETONE 78-93-3 BENZENE 34030 71-43-2 METHYL ISOBUTYL KETONE 108-10-1 TOLUENE 34010 108-88-3 ETHYLBENZENE 34371 100-41-4

4-24 TABLE 4-9 MINNESOTA DEPARTMENT OF HEALTH METHOD 465B ANALYTES

PARAMETER STORE! NUMBER CAS NUMBER

34418 74-87-3 UICHi.OKGQIfLUOROMETHANE 34668 75-71-8 VINYL CHLORIUE 39175 75-01-4 BrtUMJMETHANE 34413 74-83-9 CHLOKGETHANE 34311 75-00-3 rtETHYLENt CHLOKluE 34423 75-09-2 TrtlCHLOROFluOROMtTriAUt' 34488 75-69-4 ALLYL ChLUKlUE 107-05-1 1,1-LlIChLOROETHYLENt 34501 75-35-4 1,1-OICHuOROETHANE 34496 75-34-3

TRANS-1 ,2-01CHLORUETHYLENE 34546 156-60-5 CIS-1 ,2-DICHLOKOETHYLENE 156-59-2 CHLORUFUKM 32106 67-66-3 1 , 1 ,2-TR I CHLOROTRIFLUOKOETHANE 76-13-1 1,2-DICHLiiROETHAMt 34531 107-06-2 DIE^OnuMETHANE 74-95-3 1,1,1-TRICHLORUETHANE 34506 . 71-55-6 TCTKACHLORIQE 32102 56-23-5

4-25 (CONTINUED NEXT PAGE) TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALYTICAL DATA NARE LONG PRAIRIE RI/FS

VOLATILE:

; 5AHPLE NUMBER 1A 1A 1A IB IB IB 2A :A »H SOUND 11 42 13 11 42 43 41 42 »3 HATRII 4ATER HATER HATER MATER HATER HATER MATER •ATER iATEr UNITS UE/L UG/L UG/L U6/L U6/L 116/L UG/L js/L .5/1.

Chloroietnane NS NS jn«oietnane N5 NS Dichlorcaifluoroiethane I NS NS :j Vinyl Chloride I NS NS ij Chloroethane NS NS flethylene Chloride NS NS 4. OB Trichlorofluoroiethane NS NS 1.1-Dichloroethyiene NS NS 0.5B 1,1-Dicnloroethane NS NS Trins-l,2-0ichloroethvlene NS NS £is-l,2-9ichloroetfiylene 5.SC NS NS Chloroiori NS NS 2.2B 1.2-5ichloroethane NS NS 0.26 1,1,1-Trichloroethane NS NS Carton Tetrjchlondi NS NS Srotooichloromhane NS NS 1.2-Dkhloropropane NS NS Ci5-l,3-Dichloro-l-prcpene NS NS 1,'1,2-Tncnloroethylene 1.3 NS NS O.SB 2.oB QibroiocMoroitthine NS NS 1,1,2-Tncnioroethane NS NS Transl,3-Dichloro-l-prooene NS NS O.SB 2-Chiorofthylvinyltther NS NS Broiofori NS NS 1,1,2,2-Tetrachlorocthinc NS IJ NS •^ i •> •Ml 1 , 1 .2,2-Tetrachloroetnylent 1.5C NS U NS 30C i...jj Chlorobenztne « NS I '

KDTES: Blank spice - cotpound analyzed for out not detected NS - not satpled

PIRNIE 4-26 '.CONTINUED NEXT PAGE' TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALYTICAL DATA WflE LONG PSAIRIE SI/F3

VCLATILES

, SAMPLE SUHBER 2B 2B 2B 2C 2C 2C/BUP 3A 3A 3A ROUND ti »2 13 11 12 13 tl <2 43 ! HATR1I WATER MATER WATER HATER MATER HATER HATER 4ATER MATER UNITS U6/L U6/L J6/L D6/L US/L U6/L U6/L U6/L U6/L

Chloroiethane NS NS NS IJ I Srowiethane SS NS NS DictiiorodiTluoroietnane NS NS I NS ! Vinyi Chlonce NS IJ NS i NS I Chlorofthane NuCa NS NS i flethyltni Chloride 16B NS NS 4.3 NS Trichlorofluoroietliane NS NS NS 1 1,1-Oichloroethyiene NS NS O.iB NS 1,1-Dichlorotthane NS NS NS 1 Trans-!, 2-Dichlorcethylen« NS 1.0 NS 1.1/1.1 NS Eis-l,2-Dichloroithylene NS l.OJ NS 0.8 1.1J/1.1J NS , Chioroforj 25B NS NS O.b NS 1,2-Dichloroethane NS NS 0.5B NS ! !,;,i-Tnchioro«th»r,e NS NS *S Caroon Tetrachlorioe NS NS NS ; Broioaicnlorcmethane NS NS NS , l,2-5ichlorooropane NS NS NS ! Cis-l,I-uichloro-!-orop«ne NS NS NS ; 1,1,2-Trichloroethvlene 12B NS l.eJ NS 4. IB 4.2J/4.6J 1.0 MS ! Dibroiochlorouthane NS NS «S i 1,1,2-Tricnlorottltant NS NS NS ! Transl,3-Dichloro-l-pronme NS NS NS 1 2-Chloroettiylvinylither NS NS NS 1 Broio^ori NS NS NS 1 1,1.2,2-TetracMoroethane NS 290 NS 130/130 IJ NS IJ ! 1,1,2,2-Tttracnloroethylene 160C NS 290 NS 210 130J/130J NS ; Chlorotenzene NS NS NS

NOTES: Blank soace - coioound analyied far but not Detected NS - not saioleo

4-27 HRNIE (CONTINUED NEXT PAG TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALYTICAL DATft NARE LONE PRAIRIE RI/FS

VQLATILEB i SAMPLE NUflBER I 3B 3B 3B 4A/DUP 4A 4A 4B/FB 4B 4B ROUND ! 11 12 13 tl 12 13 11 12 13 riATRIl 1 HATER HATER HATER HATER HATER HATER HATER HATER HATER UNITS i U6/L U6/L U6/L UB/L U6/L U6/L U6/L UB/L UE;L

Chloroiethane ! NS NS NS Sro«o«inane ! NS NS NS DichlorodHiuoroiethane I NS NS ,'X NS Vinyl Chloride ! NS NS 11 NS Chloroethane 1 NS NS l\ NS Nethylene Chloride i NS NS 166/ NS Trichlorofluoroiethane 1 NS NS NS 1,1-Dichloroethylene i NS 0.5B NS NS 1,1-Dichloroethane I NS NS NS Trans-l,2-Dichloroethylene ! NS NS K3 l.l 1 1 Cis-l,2-Dicftlor«thYl«nt i NS 0.7/ NS NS * • i Chlorofon ! NS 1.7B/1.4B NS 24B/ MS 1,2-Dichloroethane ! NS 0.3B l.W NS NS 1,1,1-Tnchloroethane i NS NS NS Caroon Tetracnlonde ! NS NS NS rroiodichloroiethane ! NS NS NS 1,2-Sichlorooropane I NS NS NS Cis-l,3-Dichloro-l-prooene ! NS NS NS 1,1,2-TrichlDrotthyltne i NS O.bB 1.1/l.BB NS 18B/ NS o.7j Dibroiochlorotethane ! NS NS NS 1,1,2-Trichlorotthint 1 NS NS NS Transl,3-Dichlofo-l-prooene! NS 0.6B NS NS 2-Chioroethylvinylether ! NS NS NS Broio^ori ! NS NS NS 1,1,2,2-TetracMoroethane i NS NS 2.0 JJ NS 30 1,1,2,2-Tetrachloroethylent! NS IJ 2.9C/5.8C NS 2.0J ISO/ NS 30 ChloroDenzene ! NS J NS ss :

KOTES: Blank space - coioound analyied for but not detected NS - not saiplea

M 4-28 (CONTINUED NEXT PAGE! TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALYTICAL DATA NAME LON6 PRAIRIE RI/FS

VOLATILE5

SAMPLE KUJ1BER 4C 4C 4C SA 5A 5A 5B/DUP SB 5i/Fr , ROUND tl tl 12 13 11 12 43 ; 42 *3 HATRIJ MATER HATER 4ATER WATER MATER MATER MATER MATER «TE* UNITS U6/L U6/L U6/L U6/L US/I U6/L UG/L U6/L uS/L

ChloroMthint NS NS Hi : BroiOMthane NS NS ! DicnloroditluoroMthane NS NS 11 i Vinvl Chloride NS NS IJ 11 ; Chloroethane NS NS ; i Methyl me Chloride NS 3.5B NS 3.77 i Trichlorofluoroiethane NS NS il ! 1,1-Dichloroethylene NS NS i 1,1-Dichloroethane NS NS i Trjns-1 ,2-Dichloroethylene NS 6.9 NS 2.1 /0.3C i.i/ : UC Cis-l,2-Dichloroethylsne 7. 1C nd 6.9J 2.0C NS 2.1J /O.iC l.U/ : Chlorofon 1.9B NS 2.53 NS /1.5B . 1,2-Dichloroeth.ane 1.0 NS NS /O.fl l.l.l-Tricnlonenane NS NS 0.6/ ; Carson Tetracnlonfle NS NS droiodicfiloroietnane NS NS • 1,2-Dichloroprooane NS NS '< Cis-l,3-Oichloro-l-proDene NS NS '• 1.1,2-Tncnloroethylene 5.6 NS 8.2J 2.7B NS 1.9/1.9 i.oj/ : : Dibroiochloroiethane NS 1.3C NS 1,1,2-Trichloroethane NS NS ] Tnn«l,3-Dichloro-l-pr opine NS NS 2-Chloroethylvinyl ether NS NS Broiofon NS NS • 1,1,2,2-Tetnchloroethane NS no NS 1.3/ . 1,1,2,2-Tetrachioroethylene 75C NS 110 1.9C NS 4.2C/2.9C l.SUJ/ i Chlorodenzene NS NS •

NOTES: Slant sotce - coipound analy:ed tor but not detected NS - not saiolea

.VULCOW P!RNIE 4-29 (CONTINUED NEXT PAGE! TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALYTICAL DATA SAHE LQN6 PRAIRIE RI/FS

VOLATILE3

! SAMPLE NUHBER 6A aA iA 1 6B oB 68 6C oC cC ROUND 11 12 13 : 11 12 «3 11 12 13 IMTRI1 HATER HATER MTER 1 HATER HATER HATER HATER HATER HATER UNITS U6/L UG/L U6/L i UE/L U6/L U6/L UG/L U6/L U6/L

Chloroiethane 2.4 OS IJ 1 NS IJ NS i Broidiethine 2.4 NS i NS NS UC Di thl orodif 1 uoroiethane 5.1 NS J NS N5 i Vinyl Chloride R NS t NS NS CMoroethane 2.8 NS ! NS NS i Hethylene Chloride 3.4 NS • NS NS TrichlorolluoroMtlune 2.5 NS i NS NS 1,1-Dichloroethylene 3.3 NS i :.2 NS NS 1,1-Dichloroethane NS i NS NS Trans-1 ,2-Dichloroethvlene NS i.7 i NS 1.9 NS 14 Cis-l,2-0ichloroethvlene 5.4C NS i.7J ! 1.3C NS 1.9J 8.7C NS 14J Chlorofori 2.0 NS i 2.9B NS 3.5B NS 1,2-Dicnloroetliane 1.9 NS i NS 4.4 NS 1.1,1-Tnchloroetnane 1.1 NS i HS NS Carbon Tetrachlonde 1.2 NS ! NS NS srot-odichiorotethane 1. a NS i NS NS 1.2-Dicnloroprooane 1.5 NS ! NS NS Cis-1 ,3-Oicnloro-l-orooene NS I NS NS 1,1,2-Tnchloroethylene 6.9 NS l.OJ 1 3.63 NS 4.2J 16 NS 38J DibroiocnloroMthane NS i NS N5 t 1,1,2-Trichloroethane NS i NS NS t Transl ,3-Oichloro-l-oropene NS i NS NS 2-Chloroethylvinylether NS i NS NS Sroiofori 1.3 NS ! NS NS 1,1,2.2-Tetracftloroethane NS 10 : NS t>5 NS 49J l,1.2,2-~etracnloroer.nylene 72C NS 1W ! 53C NS oSJ 340C NS 49J CMorooenzene NS 1 NS NS

(KITES: space - coipouno analyzed tor but not Detected

NS - not saipled

VWCOLM PIRNIE 4-30 ICONT1NUED NEXT PAGE! TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALVTICAt DATA NAME LONG PRAIRIE RI/F5

VOLATILES

SAMPLE NURSES 7A 7A 7A 9A 9 9 10 ; 10 , lO/DUP , .ROUND 11 12 13 tl 12 13 41 42 43 IWTRII MATER MATER MATER HATER MATER MATER MATER MATER MTES UNITS U6/L U6/L U6/L U6/L U6/L U6/L U6/L U6/L jS/L i

Chlorot-ethane NS NS NS NS Broioiethane NS NS NS XJ NS NS , DichlorodifluoroMthane H NS NS NS NS NS 2.6/ i Vinyl Chloride I NS NS NS NS NS Z.i/ , Chioroethane NS NS NS NS NS ; i ncthyltne Chloride NS NS NS NS NS i Tricolor ofluoroiethane 0.7 NS NS NS NS NS ! 1,1-Dichloroethylene NS NS NS NS NS o.aj : 1,1-Dichloroethane NS NS NS NS NS ! Trans- 1 , 2-Di chl oroethy] ene NS NS NS NS NS o8/52 1 Cis-i,2-Dichloro*thylene NS NS NS NS NS 68J/52J ; Chloroion NS NS NS NS NS 1,2-Dicnlorotthane 0.5 NS NS NS NS NS i 1,1,1-Trichloroetnane 0.5 NS NS NS NS 13 0.9 . Carbon Tetrachlonde NS NS NS NS NS [ Sroiodicniorwethane X NS NS NS NS NS i 1,2-Dichloropropane NS NS NS NS NS ; Cis-1 ,3-Dichloro-l-propene NS NS NS NS NS 1,1,2-Tncnloroethylene NS NS 1.0 NS U NS « 640J/300J; Dibroiochloroiethane NS NS NS NS NS 1,1,2-Trichloroithani NS NS NS NS NS : Transl,3-Dichloro-l-propene NS NS NS NS US ; 2-Chloroethylvinylether NS NS NS NS NS Broiofori NS NS NS NS IS \

Q 1 H 1,1,2,2-Tetrichloroethane NS NS NS ^•4. NS NS ::ouo/tf : 1,',2.2-Tetrachloroetnvlene I NS NS NS 2.2UJ NS NS 22000J/t 1 Chlorobenzm NS NS NS NS KS ' NOTES: Slant spaci - coipouno analv:ed for aut not aetected » ROUND 3 MELL 10 DUP - 17000J » ROUND 3 MELL 10 DUP = 17000 NS - not saipied

.V1AU3DLM PIRNiE 4-31 (CONTINUED NEXT PAGE! TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALYTICAL SATA KANE LONG PRAIRIE RI/FS

VOLATILES

; SAMPLE MJN8ER 11 11 11 13C 13C/DUP 13C 14B 14B .48 ' ROUND fl <2 43 tl 12 13 11 « 43 1ATRH HATER MATER HATER HATER WATER HATER HATES iA!ER lATER UNITS U6/L U6/L UG/L UG/L U6/L UG/L UG/L U6/L UB;L ;

Chiorciethane NS NS NS BroiMtttune NS MS NS Dicnloradifluoroiethane NS NS NS Vinyl Chlono* NS NS NS Chloroetnane NS NS NS Rethylene Chloride NS NS NS Trichlorofluoroiethane NS NS NS l,l-Dichloroethy!ene NS O.SB NS O.S/0.6B NS O.iB l,l-Dkhloroethane NS NS NS Trans-l,2-5ichJoroethylene NS NS NS Cis-l,2-Dichloroetnylene NS NS 0.7/0.7 (J NS 0.4 IJ Chlorofon NS NS NS 1,2-Dicnloroethane NS 0.3B NS 0.4B/0.4B NS 0.4B 1,1,1-Tnchlorcethane NS NS 11 NS Caroon Tetracnlonde NS NS NS Brotodichioroiethane NS NS NS 1,2-Dichloroprcpant NS NS NS C;s-l,3-Dichloro-l-propene NS NS NS 1,1,2-Trichloroethylene NS O.bB NS 0.7B/0.7B NS 0.86 L] Dibroiochloroiethant NS NS NS 1,1,2-Trichloroethane NS NS NS Transl,3-Bichloro-l-proptne NS 0.6B NS 0.7B/0.7B NS 0.6B 2-Chloroethylvinyltther NS NS NS Broiofori NS NS NS l,:.2.2-Tetracnloroethane NS NS NS 1,1 .2.2-T«tracnloroetnyiene NS IJ NS NS Chlorgbenzene NS 1 NS III NS I

NOTES: Blint spice - caipound analyzed tor out not detected

NS - not suplea

M 4-32 (CONTINUED NEXT PAGE! This condition is reversed, though, for the analytical results from monitoring well 5. The same three major contaminants found in municipal well 4 are also found in municipal well 5, although at lower concentrations. MDH analytical results for the same period, 1983 and 1984 are significantly higher for all three, especially for PCE. MDH results generally decreased with time from 280 to 100 ug/1. The lower value obtained during the RI, 24 ug/1, continued the downward trend. Analytical results from each of the three rounds from municipal well 6 do not indicate contamination. While results from Round 1 indicate low levels of chloroform, 1,2-dichloroethane, and 1,1,2-trichloroethylene present (1.1, 0.6, and 1.2 ug/1 respectively), they are not confirmed in the two later rounds of analyses. 4.3.2.2 Monitoring Wells - All previously existing and new monitoring wells except MW-7A were sampled at least twice during the remedial investigation. Monitoring well 7A could not be sampled a second time due to an ice obstruction in the casing. Monitoring wells 6C and BAL-2B were sampled during all three rounds. Analytical results for all monitoring wells are given in Table 4-10. Analytical results from each monitoring well are discussed below. MW-1A; - Analytical results from this previously existing monitoring well indicate very low levels (less than 1.5 ug/1 each) of the three main contaminants: cis-1,2-dichloroethylene, 1,1,2-trichloroethylene, and 1,1,2,2-tetrachloroethylene. However, the presence of these contaminants was not confirmed in a second sample from that well. In general, the RI results from MW-1A compare favorably with the low levels detected during MDH surveys conducted in 1984. MW-1B: - Analytical results from samples obtained from this newly installed monitoring well did not indicate contamination. MW-2A - This is a previously existing monitoring well. While 30 ug/1 of PCE was detected in the first round analysis, it was not confirmed in the second analysis. The RI analytical results indicate considerably less contamination

REPT4/tdg 4-42 than those of MDH obtained in 1984 when a concentration of 160 ug/1 of PCE was detected. MW-2B; - Analytical results from previously existing monitoring well 2B confirm high levels of PCE (160 and 290 ug/1). Significant levels of cis-l,2-dichloroethylene and 1,1,2-trichloroethylene were not confirmed in the RI. MDH results showed higher levels of PCE (520-1200 ug/1) and also of the other two contaminants (23-48 ug/1). MW-2C; - This is a newly installed monitoring well. Analytical results also indicate high levels of PCE (210 ug/1) although much lower levels of the other two contaminants (less than 5 ug/1). MW-3A; - The first round of analyses from a sample from this well showed very low levels of five contaminants. An analysis of a second sample from MW-3A showed only indistinguishable levels of two contaminants, one of which, 1,1,2,2-tetrachloroethane was also noted at an indistinguishable level (less than Detectable limits) in the first sample. Comparing to MDH results, it would not appear that contamination of groundwater from this well has been established. Further monitoring of this monitoring well is, however, still warranted. MW-3B; - This is a newly installed monitoring well. Analytical results did not indicate contamination. MW-4A; - Analytical results of samples from this previously existing well indicate very low levels of PCE contamination (2.0-5.8 ug/1) and lower levels of the other contaminants. MDH analytical results obtained in 1984 showed a considerably higher level of PCE (1100 ug/1) and cis-1,2-dichloroethylene (34 ug/1) and 1,1,2-trichloroethylene (15 ug/1). MW-4B; - This is also a previously existing monitoring well. High levels of PCE (80-150 ug/1) were detected in samples obtained during the RI although they are slightly lower than those detected by MDH (110 to 210 ug/1). Levels of the other two contaminants are similar but slightly lower than those obtained by MDH.

REPT4/tdg 4-43 MW-4C; - Analytical results from this previously existing monitoring well confirm PCE at high levels (75-110 ug/1). These are higher levels than those detected by MDH (20 ug/1). Concentrations for cis-1,2-dichloroethylene and 1,1,2-trichloroethylene are similar to those detected by MDH (5.6-8.2 ug/1). MW-5A; - Analytical results of one of the two samples from this previously existing monitoring well indicate a low level of PCE (1.9 ug/1). PCE was not detected in MDH analyses, Cis-1,2-dichloroethylene was also present at a low level (2.0 ug/1) similar to that detected by MDH (2.7 ug/1). 1,1,2- Trichloroethylene is not reliably found in the RI results although it was detected at 2.6 ug/1 by MDH. MW-5B; - This is a previously existing monitoring well. Analytical results obtained during the RI and by MDH indicate low levels of PCE contamination (2.9-7.6 ug/1) and lower levels of the other contaminants. MW-6A; - This is a previously existing monitoring well. An analysis of the first sample from this well obtained during the RI indicated low levels of 17 compounds. However only cis-1,2-dichloroethylene, 1,1,2-trichloroethylene, and PCE were detected in a second analysis. The levels detected in both analyses (5.4-6.7, 1.0-6.9, and 10-72 ug/1, respectively) were less than those detected by MDH in 1984 (37, 29, 520, respectively). MW-6B: - Analytical results from samples obtained from this previously existing well indicate PCE contamination at 53-65 ug/1. Levels of the other two contaminants are less than 4 ug/1. These levels are considerably lower than those detected by MDH in 1984 by an order of magnitude of 1 to 2. MW-6C; - This is a previously existing monitoring well. Levels of all three contaminants are higher in MW-6C than most of the other monitoring wells. PCE concentrations in RI samples ranged from 49-340 ug/1 as compared with 160-330 ug/1 obtained by MDH; cis-1,2-dichloroethylene was detected at 8.7 ug/1 during the RI and at 8.2 by MDH. 1,1,2-Trichloroethylene was detected at 16-38 ug/1 during the RI and at 17 ug/1 by

REPT4/tdg 4-44 MDH. Full hazardous substance list (HSL) analyses were conducted on the Round 2 sample from MW-6C. No contaminants in fractions other than the volatile fraction were detected. MW-7A; - This is a previously existing well. Neither RI or MDH results indicated contamination. MW-9A; - This is a previously existing well. 1,1,2- Trichloroethylene was detected at a low level of 1.0 ug/1 • during the RI and at a concentration of 1.9 ug/1 by MDH in 1984. The other contaminants were not confirmed present during the RI nor by MDH. MW-10; - This is a new monitoring well installed immediately downgradient of the suspected source of groundwater contamination. The highest levels of contamination were detected in MW-10. PCE was confirmed present at 13000-22000 ug/1, cis-l,2-dichloroethylene was found present at 52-68 ug/1, and 1,1,2-trichloroethylene was found at 300-660 ug/1. MW-11: - This is a newly installed monitoring well. Contamination was not confirmed in this well. MW-13C; - This is a newly installed monitoring well. Contamination was not confirmed in this well. MW-14B; - This is also a newly installed monitoring well. Contamination at appreciable levels was not confirmed in this well although there is a slight indication that very low levels of cis-l,2-dichloroethylene and 1,1,2-trichloroethylene may be present. MW-14C; - This is a newly installed monitoring well. Contamination was not confirmed in this well. BAL-2B; - Analyses from this previously existing monitoring well did not confirm contamination. BAL-2C; - Analyses from this previously installed monitoring well indicates very low levels of 1,2-dichloroethane (0.9 - 1.7 ug/1). This contaminant is found in other wells including MW-4A, 4C, 5B, 6A, 6C, 7A, and Municipal well 5. However, in all cases except for BAL-2C, its presence was not confirmed in a second analysis.

REPT4/tdg 4-45 4.3.2.3 Residential Wells; - Samples from nine residential wells in the northeastern quadrant of Long Prairie were obtained during round 1 of the RI. These included the following: NO. ADDRESS OWNER 1. 610 5th Ave. NE L. Schroeder 2. 216 6th St. NE K. Werner 3. 405 6th St. NE A. Plemel 4. 410 1st Ave. N W. Werlinger 5. 214 1st Ave. N G. Harren 6. 314 6th St. NE B. Mueller 7. 116 6th St. NE R. Hokanson 8. 321 3rd Ave. N J. Neidhart 9. 602 6th St. NE F. Starry In general, analytical results (given in Table 4-7) from samples of these residential wells did not show contamination and compared favorably with those of MDH. However, analysis of the Werlinger well showed PCE present at 2.1 ug/1. MDH results from this well showed to 230 ug/1 of PCE detected in October, 1983 and less than detectable levels of PCE found in April, 1985. The same MDH results for cis-1,2-dichloroethylene are 0.4 and less than detectable, respectively. Analytical results from the Harren well confirmed cis-1,2-dichloroethylene at a low concentration of 0.5 ug/1. MDH results from the Harren well obtained in November, 1983 indicate PCE, cis-1,2- dichloroethylene, and 1,1,2-trichloroethylene present at 2, 0.2, and 0.2 ug/1, respectively. In two cases (Municipal well 4 and monitoring well 4C) PCE concentrations found during the RI were greater than those found by MDH in 1984. In other cases (Municipal well 5, and monitoring wells 2A, 2B, 4A, 4B, 6A, 6B), PCE concentrations were lower than those detected by MDH. The most plausible explanation for these variations would seem to be that groundwater monitoring conducted by MDH and Malcolm Pirnie intercept- ed "slugs" of varying contaminant concentration over the two year period from the different groundwater monitoring locations, Slugs of varying concentrations are likely due to lesser and

REPT4/tdg 4-46 greater amounts of water percolation during alternating dry and wet weather periods through areas of contaminated soils. Monitoring conducted over a long period of time and at relatively short time intervals would verify this situation. 4.3.3 Groundwater Contamination Assessment and Migration 4.3.3.1 Groundwater Modeling The movement of 1,1,2,2-Tetrachloroethylene (PCE) through the Long Prairie Sand Plain aquifer was evaluated at the investigation level using the U.S.G.S. computer model of Two - Dimensional Solute Transport and Dispersion in Ground Water which was compiled by Konikow and Bredehoeft in 1978. This two dimensional model was chosen based on its applicability to the single layer aquifer present as well as its ability to incorporate several site specific hydrogeologic variables. The purpose of applying the computer model to this problem was to answer a series of questions concerning future movement and ultimate fate of the contaminant plume. The main questions addressed in this computer simulation were as follows: 1. Is municipal well #6 in danger of becoming contaminated by the known PCE plume? 2. What will happen to the Sand Plain aquifer and the PCE plume if no action is taken? 3. What effect, if any, will restarting municipal well #4 have on the PCE plume movement. 4. What effect will installing a series of recovery wells have on the PCE plume movement? The Konikow and Bredehoeft model simulates solute transport in flowing groundwater. It is applicable to one or two dimensional problems involving either steady state or transient flow. The model computes changes in concentration over time caused by the processes of convective transport, hydrodynamic dispersion, and mixing or dilution from fluid sources. The model couples the groundwater flow equation with the solute transport equation. The computer program uses an

REPT4/tdg 4-47 alternating-direction implicit procedure to solve a finite- difference approximation to the groundwater flow equation, and it uses the method of characteristics to solve the solute transport equation. Both cumulative and chemical mass balances are calculated by the program. Mass balance errors are commonly the greatest during the first several time increments, but tend to decrease and stabilize with time. The data input format for the model requires from seven to nine data sets to describe the aquifer properties, boundaries and stresses. The numerical methods require that the area of interest be subdivided by a grid into a number of smaller subareas. The model utilizes a rectangular, uniformly spaced, block centered, finite difference grid, in which nodes are defined at the center of the rectangular cells. The model allows the specification of any number of injection or withdrawal wells and of spatially varying diffuse recharge or discharge, saturated thickness, transmissivity, boundary conditions, initial heads and initial concentrations. The model can be applied to a wide variety of field problems, but some important assumptions and limitations are inherent in the model. Seven major assumptions have been incorporated as follows: 1. Darcy's Law is valid and hydraulic head gradients are the only significant driving mechanism for fluid flow. 2. The porosity and hydraulic conductivity of the aquifer are constant with time, and porosity is uniform in space. 3. Gradients of fluid density, viscosity and temperature do not effect the velocity distribution. 4. No chemical reactions occur that affect the concentration of the solute, the fluid properties or the aquifer properties. 5. Ionic and molecular diffusion are negligible contributors to the total dispersive flux.

REPT4/tdg 4-48 6. Vertical variations in head and concentration are negligible. 7. The aquifer is homogeneous and isotropic with respect to the coefficients of longitudinal and transverse dispersivity. The Long Prairie Sand Plain is a single layer, relatively uniform aquifer for which the use of a two-dimensional model is appropriate. The first six of the seven major assumptions listed above upon which the model is based are applicable to this area. Although vertical variations in head have not been documented, no evidence exists indicating confined conditions within the study area. Vertical variations in PCE concentrations do exist; however, all data was considered prior to modeling and a worst case scenario was used for the initial condition in order to impart a conservative bent to the model interpretations. The model does not address the thickness of the PCE plume. This was not considered the parameter of main concern in regards to determining health risk assessment. The model was instead configured to predict the areal extent of the plume and its migration over time. It was believed more important to determine whether the health advisory area should be enlarged or if the plume approached and contaminated the currently operating wells than to pinpoint vertical variations in concentration gradient. Given this intended use of the model, all assumptions were considered met and valid. 4.3.3.2 Model Calibration The scale of the model was chosen in order to include the known PCE plume, municipal well #4, municipal well 16 and the Long Prairie River. The modeled area covers just under one square mile. Each grid block is 220 feet by 260 feet. The grid consists of 18 columns and 17 rows resulting in a total of 306 nodes. This scale was appropriate to evaluate the overall area but did not provide enough detail for the design of an optimum contaminant recovery system. The eastern and southern edges of the grid were designated as no flow boundaries due to the pinching out of the aquifer

REPT4/tdg 4-49 at the south edge and the topographic influence and groundwater flow direction at the eastern edge. The western edge of the grid was also designated as a no flow boundary due to the general direction of groundwater flow. The area along the northern edge of the grid and a line across the northwest corner where the Long Prairie River and the associated wetlands cross the grid were designated as constant flux boundaries. Municipal well No. 6 is located on a node 220 feet west of a no flow boundary and 520 feet south of a constant flux boundary, Municipal well No. 4 is located on a node near the center of the grid. The model input matrix for recharge allows values to be varied in space. An initial value for areal precipitation was assigned based on records of locally recorded precipitation. However, during the initial calibration runs, it became obvious that the thinner portions of the aquifer could not absorb this recharge without resulting in head buildups that would have theoretically exceeded the ground surface. The recharge at each node was then adjusted during the calibration procedure as one factor in matching actual aquifer conditions. Aquifer transmissivity values were determined from pumping tests described elsewhere in the RI report. Hydraulic conductivity values were assigned to various areas of the aquifer based on the measured thickness where soil boring information was available and from the calculated thickness between control points. The till layer present was addressed as representing the bottom or lower boundary of the aquifer. The potentiometric surface maps, in this case, water table maps, were used as presented earlier in the RI report. Seepage fluxes and cumulative mass water balance were calculated by the model with results as discussed above. The mass water balance calculations account for recharge and withdrawal, water released from storage, leakage into the aquifer and leakage out of the aquifer, cumulative net leakage and a mass balance residual. The mass balance error, as percent is also calculated and presented below.

REPT4/tdg 4-50 All input parameters underwent a qualitative sensitivity analysis during calibration of the model. Modeled groundwater elevations were found to be most sensitive to changes in transmissivity and areal recharge. However, due to the limited available data base a detailed statistical approach to sensitivity analysis was not considered appropriate. The groundwater flow portion of the model was calibrated to measured groundwater elevations for unsteady state flow during pumping conditions and for steady state flow during nonpumping conditions. In this application the modeled groundwater elevations were most sensitive to changes in transmissivity and areal recharge. Transmissivity and storativity values were determined from the results of 72 hour pumping tests described elsewhere in this report. Data for static water levels and aquifer thickness were obtained from the monitoring wells installed as part of the pumping tests. The aquifer is essentially a wedge of out wash sand and gravel approximately 60 feet thick near municipal well #4 but thins to less than 5 feet to the southeast and may be locally absent beyond. An average transmissivity value of 25,000 gallons per day per foot was used in the area around municipal well No. 4. However, the transmissivity values for the remaining portions of the aquifer were adjusted based on the measured and calculated aquifer thickness in order to maintain a relative hydraulic conductivity as required for modeling. Areal diffuse recharge was also adjusted in order to match modeled water levels with actual measured water levels. Initial concentration of PCE was based on the most recent groundwater sampling as described earlier in this report. The recent data was obtained from the new monitoring wells, but data on PCE concentration in private wells was also included in the model. Although sampling events were separated in time, all available data was considered in order to present a reasonable worst case scenario for the current PCE plume configuration as shown in Figure 4-10. Some vertical variation in PCE concentration was measured in the field as would

REPT4/tdg 4-51 INITIAL CONCENTRATION

MUNICFAL WELL No. 6

MUNICPAL WELL No. 4 y

PNO CLEANERS

MALCOLM PIRISilE PCE SOLUTE TRANSPORT SIMULATION FIGURE 4-10 be expected given the physical properties of the contaminant. These vertical variations were averaged in order to satisfy modeling requirements. Plume movement in the model environment is a function of total dispersivity as well as the ratio of longitudinal to transverse dispersivity. Different values for these two variable matrices were tested in conjunction with the calibrated flow model until a reasonable fit to the currently measured plume geometry was achieved. 4.3.3.3 Model Simulation Results Three general simulations were run in order to evaluate the PCE plume movement under different conditions. The first simulation represents a No Action scenario and predicts plume movement over a 10 year period under the influence of groundwater flow only. The second simulation represents the effect of restarting municipal well #4 on plume movement also over a 10-year period. The third simulation represents the effect of pumping a series of 4 recovery wells in conjunction with municipal well No. 4. 1. No Action Simulation This simulation was run to evaluate plume movement as if nothing was done to remediate the contamination and well #4 remained shut down but municipal well #6 continued to pump at its present rate. Figure 4-11 represents the plume movement after a period of 5 years and Figure 4-12 represents the plume movement after a period of 10 years. The model indicates that the plume will not drastically change position with time but will move slowly in a northerly direction along with the natural groundwater flow. The portion of the plume with the highest initial concentration, near the Long Prairie Cleaners, will slowly disperse and decrease in concentration while moving northward at a rate of approximately 0.435 feet per day. The portion of the plume with the lower initial concentration, near municipal well 14, will also disperse and decrease in concentration but at a much slower rate. Overall plume movement in the no action simulation is to the north rather than to the north east as reflected in the

REPT4/tdg 4-52 CONCENTRATION - NO ACTION SIMULATION - 6 YRS

MUNICPAL WELL No. 6

^1 MUNICPAL WELL No. 4

PND CLEANERS

MALCOLM PIHMIf INC PCE SOLUTE TRANSPORT SIMULATION PIRNIE FIGURE 4-11 CONCENTRATION - NO ACTION SIMULATION - 10 YR8

MUNICFAL WELL No. 6

\ ° MUNICPAL WELL NO. 4

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PND CLEANERS

MALCOLM H«NH. INC MALCOLM PIRNIE PCE SOLUTE TRANSPORT SIMULATION FIGURE 4-12 initial plume orientation. The model indicates that municipal well No. 6 does not appear to be in danger of contamination from the known PCE plume. However, the model indicates that the contaminant plume will remain in the same general area for some time to come. 2. Municipal Well No. 4 Pumping This simulation was run to evaluate plume movement as if municipal well No. 4 was restarted and allowed to pump at its full capacity while municipal well No. 6 also continued to pump. Figure 4-13 represents plume movement after 5 years and Figure 4-14-represents the movement after a 10 year period. The model indicates that the plume will disperse somewhat transversely but will continue to be drawn toward well #4. The portion of the plume with the highest initial concentration will continue to be drawn in that direction but will lengthen in a north-easterly direction due to the effect of municipal well No. 4 on the longitudinal dispersivity. The portion of the plume with the lower initial PCE concentration will essentially be removed by the pumping at well No. 4, but the remainder of the plume will slowly migrate toward the well under the influence of pumping and the PCE concentration in the area of municipal well No. 4 will gradually increase as the main body of the plume approaches the well No. 4. Overall plume movement in this simulation with well No. 4 pumping is indicated to be toward the northeast. The model indicates that municipal well No. 4 should effectively divert the plume from moving past its location and that municipal well No. 6 does not appear to be in danger of contamination from the known PCE plume under these conditions. However, the model also indicated that municipal well No. 4 by itself will not effectively remove the mass of contaminated groundwater in any reasonable time frame. 3. Recovery Wells This simulation was run to evaluate the effect of a series of recovery wells on plume movement and potential remediation. The actual placement, depth and pumping rate of

REPT4/tdg 4-53 CONCENTRATION - MUNICIPAL WELL * 4 PUMPING - 6 YR3

MUNICFAL WELL No. 4

MALCOLM FIRHIC. INC MAUCXXM PIRNIE PCE SOLUTE TRANSPORT SIMULATION FIGURE 4-13 CONCENTRATION - MUNICIPAL WELL * 4 PUMPING - 10 YRS

MUNICV»AL WELLNo. e 0

r* >»AUHIC PAL'VELL No. 4 / f

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UALCOI.M PlKNIt. INC MALCOLM PIRNIE PCE SOLUTE TRANSPORT SIMULATION FIGURE 4-14 any series of recovery wells installed at this site will need to be designed very carefully due to the varying aquifer transmissivity as the sand wedge thins through the area of concern. Several combinations of well placement and pumping rates were simulated but Figures 4-15, 4-16, 4-17 show one potential combination that appears to effectively remove the contaminant plume without causing excessive drawdown in the aquifer. In this simulation, one recovery well is placed at the suspected source, municipal well No. 4 is pumping at a reduced rate and three additional recovery wells are located along the plume and are operating at varying rates. The hypothetical pumping rates vary from 90 gallons per minute at municipal well No. 4, down to 18 gallons per minute at recovery well No. 1. The model indicates that after one year under these conditions the shape and size of the plume do not change drastically but a significant concentration of PCE appears to have been removed although concentrations of just over 200 ug/1 will remain as shown on Figure 4-15. After three years of pumping under these conditions the plume appears to be reduced significantly in size and concentrations have decreased to just over 100 ug/1 as shown in Figure 4-16. The model further indicates that after 5 years of pumping under these conditions almost all of the plume appears to have been removed and that only a small area remains with PCE concentrations at about 50 ug/1 as shown on Figure 4-17. Overall plume movement in this simulation indicates that a system of recovery wells appears to effectively remove the PCE plume within a reasonable amount of time. Model predic- tions of the time necessary for remediation are minimal compared to actual operating systems but are consistent with respect to high initial efficiency and long term decreasing recovery rates. It must be noted that this simulation does not represent an actual design of a recovery system but illustrates conceptually the effectiveness of such a system. The scale at which these simulations were run is not sufficient to allow for consideration of small local variations in

REPT4/tdg 4-54 CONCENTRATION - 4 RECOVERY WELLS - 1 YR

MUNICPAL WELL No. 4

MALCOLM PIRNIt. INC PCE SOLUTE TRANSPORT SIMULATION FIGURE 4-15 CONCENTRATION - 4 RECOVERY WELLS - 3 YRS

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MAUCQLM PIRNIE PCE SOLUTE TRANSPORT SIMULATION FIGURE 4-17 groundwater flow, gradient and changes in transmissivity. A more detailed, large scale modeling effort would be needed for actual system design along with field verification. 4.3.3.4 Mass Balance and Accuracy The model calculates both cumulative mass water balance and chemical mass balance. In the no action scenario, the cumulative mass water balance was calculated showing a total mass balance error of 0.02 percent due to a slight negative mass balance residual. The chemical mass balance error ranged from 2 to 7 percent in the first few time steps as is typical of this numerical model, but leveled off to less than 1 percent and was calculated at 0.51 percent at the end of the 10-year no action simulation. The cumulative and chemical mass balance errors were maintained at similar levels during the pumping simulations. With Municipal well No. 4 pumping the cumulative mass water balance error was calculated to be 0.01 percent and the chemical mass balance started at 7 to 8 percent but leveled off and ended the simulation at 0.66 percent. With the four hypothetical recovery wells pumping the cumulative mass water balance, error remained at 5.9 percent throughout that simulation. 4.3.3.5 Conclusions The model simulations all indicate that municipal well No. 6 does not appear to be in danger of contamination from the known PCE plume. This is indicated for both the no action scenario and the scenario in which municipal well No. 4 is restarted. Restarting municipal well No. 4 will have only a minor effect on contaminant remediation but will influence plume movement along presently known trends. However, in either of the first two scenarios the Sand Plain aquifer in the vicinity of Long Prairie will remain contaminated and essentially unusable as a potable water supply for quite some time into the future. The third simulation indicates that conceptually a series of five recovery wells would be effective in removing most of the PCE contaminated groundwater. The simulation further

REPT4/tdg 4-55 indicates that the operation would require a period of approximately three to five years to complete the removal. However, a specific model run at a more detailed scale would be necessary for the actual design of the most efficient and properly balanced recovery system if a groundwater remediation option is chosen.

REPT4/tdg 4-56 5.0 SURFACE WATER AND SEDIMENT INVESTIGATION

Possible contamination of water and sediment were not investigated during this RI. Based on a review of background information, it was not warranted to undertake these tasks due to the nature of the contamination problem in Long Prairie.

REPT4/tdg 5-1 6.0 AIR INVESTIGATION

The air investigation conducted during this RI was limited to real-time ambient monitoring during drilling activities. The monitoring was performed as an ongoing health and safety requirement and to assist in the selection of subsurface soil samples. Air monitoring using a photoionization instrument was conducted in the immediate work area. Positive HNu readings were recorded while drilling commenced at monitoring well 10 and at test boring A. Boring 10 showed the highest response on the HNu with values ranging from a high of 460 to a low of 0 with high values concentrated in the saturated zone. Soil boring TB-A had the only other responses to the HNu with values ranging from 0-136. HNu values are given in the boring logs included in Appendix A. These locations are both located on Figure 1-3. The readings abated following installation of the well and filling in of the test boring. HNu readings were not recorded during the installation of test boring C due to equipment malfunction during severe cold weather.

REPT4/tdg 6-1 7.0 BIOTA INVESTIGATION

Possible contamination of biota was not investigated during the RI. Based on a review of background information, it was not warranted to undertake this task due to the nature of the contamination problem in Long Prairie.

REPT4/tdg 7-1 8.0 BENCH AND PILOT SCALE STUDIES

Bench and pilot scale studies were not undertaken as part of the RI. These studies may be recommended as part of the feasibility study.

REPT4/tdg 8-1 9.0 PUBLIC HEALTH AND ENVIRONMENTAL CONCERNS

9.1 Introduction This section presents a discussion of potential public health impacts associated with chemical contamination in groundwater at the Long Prairie site. An evaluation is made of site conditions in the absence of any interim remedial measures. For example, although two of the Long Prairie municipal supply wells have been shut down and bottled water has been supplied to a number of residents in the vicinity of the site, the evaluation assumes that there is no source of water other than from the contaminated municipal supply wells and the private supply wells. Following a brief summary of the analytical results, human receptors that may be affected by the chemical contamination are identified and public health concerns associated with exposure to the contamination are presented. The need for and the extent of the Health Advisory Area is also evaluated. While largely qualitative, this information will contribute to the determination of remedial objectives for the site. Potential environmental impacts, including potential impacts on Long Prairie River, are unlikely given the hydro- geological regime and the physical and chemical properties of the chemical contamination. Guidance in the preparation of this section was obtained from the USEPA Superfund Public Health Evaluation Manual (USEPA, 1986).

9.2 Summary of Analytical Results Analyses of groundwater samples collected from Long Prairie Municipal Wells Nos. 4 and 5 in August and October, 1983 indicted that these wells were contaminated by tetrachloroethylene (PCE), cis-1,2-dichloroethylene and trichloroethylene (TCE). The two wells were shut down in October,

REPT4/tdg 9-1 1983. Over the period August 25, 1983 to October 10, 1984, concentrations of these contaminants ranged as follows: PCE, 17.0 to 280 ug/1; cis-1,2-dichloroethylene, 0.60 to 17.0 ug/1; and TCE, 0.60 to 11.0 ug/1. These contaminants were detected in samples collected during the RI from municipal wells nos. 4 and 5 in the same concentration ranges. Munici- pal wells nos. 3 and 6, also sampled during the RI, were essentially free of contamination, although well No. 6 showed about a part per billion (1.2 ug/1) of TCE during the first sampling round. On November 1, 1983, the MDH issued a health advisory for residents with private wells in a 15 block area of Long Prairie. The advisory was based on analyses which determined levels of PCE ranging from 5 to 510 ug/1 in groundwater from 9 of 21 private wells sampled. The MDH recommended that wells with PCE concentrations in excess of 500 ug/1 not be used for any purposes and wells with PCE concentrations greater than 8 ug/1 not be used for consumptive purposes such as drinking and cooking. Residents in the Health Advisory Area were provided with bottled water for a time after the issuance of the advisory. Since November 1983, a number of residents have connected to new municipal distribution lines. Prior to the RI, groundwater samples from 48 private wells had been analyzed, some as many as three times, over the period October 26, 1983 to April 26, 1985. Concentrations of the contaminants of concern ranged as follows: PCE, non-detectable to 1000 ug/1; cis-1,2-dichloroethylene, non-detectable to 250 ug/1; and TCE, non-detectable to 110 ug/1. The monitoring well data generated during the RI, as presented in Section 4, showed a more extensive plume of groundwater contamination than determined from earlier sampling events.

REPT4/tdg 9-2 9.3 Potential Receptors The City of Long Prairie has a population of approximately 2,500 people, approximately two thirds of whom rely on the municipal water supply system. The remainder obtain water from private supply wells. The health concern remains for those residents with private wells, as well as for those residents that obtain their water from the municipal supply system.

9 .4 Health Concerns The human exposure pathway of concern in Long Prairie is via groundwater, whether it is supplied municipally or obtained from private supply wells. Exposure may occur via drinking or non-drinking water use of the groundwater. Recently, research has suggested that ingestion of contaminants in drinking water may not constitute the sole or even primary route of exposure (Andleman et al., 1986; Symms 1986; Brown et al., 1984). The release of volatile organic contaminants from bath or shower water can result in inhalation exposures that may be significant when compared to direct ingestion of these contaminants (Andleman et al., 1986; Symms, 1986). Similarly, skin absorption of contaminants in water during washing and bathing activities may constitute a significant exposure route compared to direct ingestion (Brown et al., 1984). Exposure from ingestion involves the use of the groundwater for drinking and cooking; inhalation exposure to contaminants volatilized from the water may occur during showering. Bathing and routine washing activities do not appear to be viable dermal exposure routes given the volatility of the chemicals and their low dermal absorption. The greatest risk to an individual is likely to occur at the private supply well with the highest contaminant concentrations; the contaminated or threatened municipal supply wells are of concern because of the larger exposed or potentially exposed population. The maximum concentrations of the

REPT4/tdg 9-3 contaminants of concern in groundwater in municipal wells 4 or 5, private supply wells and monitoring wells, determined during the RI or previously, are presented in Table 9-1. The mean contaminant concentration in municipal wells 4 or 5 and the monitoring wells, calculated from the available data set, are also presented. These concentrations are compared in Table 9-1 to applicable or relevant and appropriate requirements (ARARs) and to other criteria as required by USEPA (USEPA, 1986). USEPA drinking water maximum contaminant levels (MCLs) developed under the Safe Water Drinking Act are the ARARs of interest to this evaluation. MCLs are maximum permissible levels of contaminants in water delivered to the user of a public water supply and represent allowable lifetime exposure levels for a 70 kg adult ingesting 2 liters of water per day. Other daily sources are considered in the development of MCLs and a margin of safety is added to protect the more sensitive members of the population. The MCLs incorporate technological and economic criteria in addition to health factors. MCls have been promulgated for TCE and vinyl chloride. Maximum and mean concentrations of TCE in groundwater exceed the 5 ug/1 MCI; the MCL for vinyl chloride is not exceeded. The other criteria presented in Table 9-1 are USEPA maximum contaminant level goals (MCLGs), proposed MCLGs and proposed MCLs developed under the Safe Water Drinking Act, Minnesota Department of Health (MDH, 1986) Recommended Allow- able Limits (RALs), and USEPA Ambient Water Quality Criteria for the protection of human health. MCLGs, which are entirely health-based, are developed by USEPA as part of the process for setting MCLs. They represent the maximum concentrations of contaminants in drinking water at which no known or anticipated adverse effect on the health of persons will

REPT4/tdg 9-4 TABLE 9-1 Comparison of Contaminant Concentrations In Ground Water to Applicable or Relevant and Appropriate Requirements (ARARs) and Other Criteria (X denotes exceedance; all units in ug/1)

ARARs Other Criteria Contaminant Nell Contaminant HCLs HCLGs PMCLs PMCLCs RALS AWQC Type Concentration

Tetrachloroethy1ene NA NA NA 6.9 0(0.88)

Municipal Max. 280 XXX Private Max. 1000 XXX Monitoring Max. 1200 XXX

Municipal Mean 136 X X Monitoring Mean 119 X X

Trichloroethylene 5 0 5 NA 31.2 0(2.8)

Municipal Max. 11 X X X Private Max. 110 X X XX Monitoring Max. « X X XX

Municipal Mean 7 X X X Monitoring Mean 6 X X X

cis-1,2-Dichl oroethy lene NA NA NA 70 70 NA

Municipal Max. 17 Private Max. 250 X X Monitoring Max. 50

Municipal Mean 8 Monitoring Mean 6

Vinyl Chloride 2 0 1 NA 0.15 0(2.0)

Municipal Max. <1.5 X Private Max. ND/NR Monitoring Max. <1.5 X

Municipal Mean <0.75 X Monitoring Mean <0.2 X

Notes: MCLs and MCLGs - USEPA Maximum Contaminant Levels and Maximum Contaminant Level Goals. PMCLs and PMCLGs - USEPA Proposed Maximum Contaminant Levels and Proposed Maximum Contaminant Level Goals. RALs - Minnesota Department of Health Recommended Allowable Limits. AWOC - USEPA Ambient Water Quality Criteria for the protection of human health. Adjusted for drinking water only as per USEPA (1986). Concentrations In parentheses correspond to the midpoint (10 ) of the risk range for potential carcinogens. NA - Not Available. ND/NR - Not detected or not reported.

REPT4/tdg 9-5 occur, and they include an adequate margin of safety. MCLGs are nonenforceable health goals. While MDH indicates that the RALs apply only to private water supply, they are compared to all the data presented in Table 9-1. The RALs for systemic toxicants, in this case cis-l,2-dichloroethylene, are based on the application of safety factors to accepted allowable daily intakes; for compounds classified as known or probable carcinogens, RALs have been calculated at a 10 (1 in 1 hundred thousand) lifetime incremental risk level. Federal ambient water quality criteria (AWQC) are estimates of ambient surface water concentration that will not result in adverse human health effects. For suspect or known carcinogens, concentrations associated with a range of incremental cancer risks (10~ , 1-" and l-~ ) have been developed, in addition to an absolute criterion of zero. For most chemicals, two exposure pathways are incorporated into the criteria: lifetime ingestion of drinking water (2 liters/day) and ingestion of aquatic organisms (6.5 g/day). AWQC, adjusted for drinking water only as per USEPA (1986), associated with a 10~ incremental cancer risk are presented in Table 9-1. The AWQC are non-enforceable. MCLSGs have been established for TCE and vinyl chloride and maximum and mean concentrations of these contaminants in groundwater at this site exceed the goals. The proposed MCL and RAL for TCE is exceeded based on the maximum concentrations, as are the proposed MCLGs and RALs for PCE and cis-1,2- dichloroethylene based on the maximum concentrations. The mean concentrations of the TCE exceed the proposed MCL while the mean concentrations of PCE exceed the proposed MCLG and RAL. It is uncertain whether the proposed MCL and RAL for vinyl chloride are exceeded. PCE and TCE levels in groundwater exceed the AWQC. Contaminant concentrations in groundwater are compared in Table 9-2 to toxicity guidelines, where available, that have been developed to evaluate toxic (but not carcinogenic) and carcinogenic health effects. A verified reference dose (RfD, formerly termed the acceptable daily intake or ADI), expressed REPT4/tdg 9-6 TABLE 9-2 Comparison of Maximum Contaminant Concentrations in Groundwater to Toxicity Guidelines (X denotes exceedance; all units in ug/1)

Well Well Maximum Toxicity Guidelines Contaminant Type Number Concentration Daily Intake Cancer Risk

Tetrachloroethylene 700 0.7

Municipal 5 260 X Private 62 1000 X X Monitoring 2A 1200 X X

Trichloroethylene NA 3.2

Municipal 5 11 X Private 3 110 X Monitoring 6B 45 X

cis-1 , 2-Dichloroethylene NA NC

Municipal 5 17 Private 3 250 Monitoring 6B 50

Vinyl Chloride NA 0.02

Municipal 5 1.5 Private ND/NR Monitoring 2 1.5

Notes:

Daily Intake - Concentration in groundwater resulting in an exceedance of the verified reference dose (acceptable daily intake) if groundwater is consumed by a 70 kg adult at a rate of 2 I/day or 2 liters per day or 2 liters/day.

Cancer Risk - Concentration in groundwater resulting in an incremental cancer risk of 10 if groundwater is consumed by a 70 kg adult at a rate of 2 /day or 2 liters per day or 2 liters/ day for a 70 year lifetime.

NA - Not available.

NC - Not carcinogenic.

ND/NR - Not detected or not reported.

REPT4/tdg 9-7 in terms of milligrams per kilogram body weight per day has been established for PCE (USEPA, 1986). The concentration in groundwater that would result in an exceedance of the RfD, if groundwater is consumed by a 70 kilogram adult at a rate of 2 liter per day, is calculated to be 700 ug/1. The maximum PCE concentrations in the municipal supply wells and monitoring wells exceed this value. Carcinogenic potency factors based on oral exposure have been developed for PCE, TCE and vinyl chloride. The concentration in groundwater that would result in an incremental cancer risk of 10~ (1 in 1 million), if groundwater is consumed by 70 kilogram adult at a rate of 2 liters per day for a 70-year lifetime, are presented in Table 9-2. The maximum concentrations of PCE and TCE exceed these values. In summary, contaminant concentrations in groundwater exceed federal and state guidelines for drinking water quality and human exposure. Under the No Action assumption that the contaminated groundwater represents the sole source of water to residents in the vicinity of the site, concerns exists for potential adverse health effects. Such concern must be considered in the development and evaluation of remedial alternatives for the site. Based on the analysis of the nine private wells samples during the RI, the plume of contaminated groundwater remains contained within the boundaries of the Health Advisory Area. At this time, the boundaries appear to be adequate to protect private wells in the vicinity of the contaminant plume.

REPT4/tdg 9-8 10.0 POSSIBLE ALTERNATIVE RESPONSE ACTIONS

10.1 Introduction This chapter will present a listing of possible alternative responses to the groundwater contamination problem at Long Prairie. It will also present an analysis to determine if sufficient data have been obtained in the RI to evaluate each of the alternative response actions during the feasibility study.

10.2 Alternative Response Actions The Work Plan identified various possible alternative response actions. These are shown in Figure 10.1. Table 10-1 lists these technologies and evaluates them in light of the RI data and information obtained for application to the groundwater contamination problem at Long Prairie. As a result of this evaluation, the following possible alternative response actions are available for further consideration during the feasibility study:

Objective Alternative Response Action Leachate and Groundwater o Containment Barrier Controls o Groundwater Pumping Waste and Soil Excavation o Excavation and Removal and Removal In-Situ Treatment o In-Situ Treatment Direct Waste Treatment o Incineration o Treatment of Aqueous and Liquid Waste Streams o Solids Dewatering and Treatment o Fixation or Encapsulation Land Disposal/Temporary o Land Disposal Storage o Temporary Storage Contaminated Water and o Alternate Drinking Supply Sewer Line Controls

REPT4/tdg 10 - 1 GENERAL RESPONSE ACTIONS

M 5 o 4 z « o O S li • ^ M Ml _J H 2 * § M U S S S o u M u K u u M o a M

S * o CONTN O 4 g| ri o WAT I I1A11O 4 MI V * M * >- M 0 j! 8 i| 9 • i H M a Z » 4 M • OIMC T WA S TNIATMIN T LIACHAT I A CONTAMMA 1 NtMOVA L A H SITE PROBLEM ONOUNOWA T O is if 8 s

CONTAMINATED 0 OMOUNDWATEM ^ ^

CONTAMINATED • OILS ^

CONTAMINATED • UILOINOS

MM.CO1I* MWM. MC. MAUGtXM LONG PRAIRIE, MINNESOTA FIGURE 10-1 RRNIE APPROPRIATE GENERAL RESPONSE ACTIONS TABLE 10-1

POTENTIALLY APPLICABLE REMEDIAL TECHNOLOGIES LONG PRAIRIE, MINNESOTA

Objective Method Applicability to Long Prairie

Leachate and Ground Water Capping - to reduce leachate Not necessary Controls generation and ground water contamination through isolation of wastes from water infiltration. Containment Barriers - to Possible prevent migration of contaminated ground water by means of a low- permeability barrier. Ground Water Pumping - to Possible remove contaminated ground water for subsequent direct treatment. Subsurface Drains - to inter- Not possible cept and/or collect leachate or contaminated ground water by gravity flow methods. Waste and Soil Excavation and Removal Excavation and Removal - to Possible remove contaminated soils for subsequent treatment or disposal. In-Situ Treatment In-Sltu Treatment - to treat Possible contaminated soils and sediments, contaminated water, contaminated building foundations and paved areas, without excavation, dredging, or pumping. Direct Waste Treatment Incineration - to reduce the Possible volume and of organlcs in contaminated water, soils, or sediments. Treatment of Aqueous and Possible Liquid Waste Streams - to biologically, chemically, or physically detoxify contaminated ground water or well water.

REPI4 / td g 10-2 TABLE 10-1 (Continued)

POTENTIALLY APPLICABLE REMEDIAL TECHNOLOGIES LONG PRAIRIE, MINNESOTA

Objective Method Applicability to Long Prairie Solids Dewatering and Possible Treatment - to treat contaminated soils and sediments for subsequent treatment or disposal. Fixation and Encapsulation - Possible to reduce the release of hazardous compounds from treated soils and sediments, or from contaminated building foundations and paved areas. Land Disposal Temporary Storage Land Disposal - to dispose of Possible contaminated soils, sediments, or building foundations/paved areas in a treatment, storage or disposal facility located on or off the site. Temporary Storage - to Possible temporarily store contaminated soils, sediments, or water prior to offsite treatment or disposal. Contaminated Water and Sewer Line Controls In-Situ Cleaning - to decon- Not necessary taminate sewer and water lines by cleaning line Interiors. Removal and Replacement - Not necessary to decontaminate water and sewer lines by removing and replacing contaminated portions. Alternate Drinking Supply - Already done in most cases. to provide a temporary or Possible in other cases. permanent means of supplying uncontaminated water to affected residents. Individual Treatment Units - Not necessary to remove toxic or hazardous wastes from residential water systems.

REPT4/td g 10 - 3 TABLE 10-1 (Continued)

POTENTIALLY APPLICABLE REMEDIAL TECHNOLOGIES LONG PRAIRIE, MINNESOTA

Objective Method Applicability to Long Prairie Backflush Protection - to Not necessary prevent introduction of contaminated ground water to the nunicipal water supply at residences with both private and municipal water supplies.

REPTWtdg 10 These alternative response actions are grouped as follows in relation to their capability to attain Maximum Contaminant Levels (MCLs), or in this case, Maximum Contaminant Level Goals (MCLGs) within alternative time periods.

Alternatives which attain Excavation and Removal MCLGs within five years. Alternate Drinking Water Supply Groundwater Pumping (with recovery wells)

Alternatives which attain Solids Dewatering and Treatment MCLGs in greater than Fixation and Encapsulation Five years. Land Disposal In-Situ Treatment Incineration Treatment of Aqueous and Liquid Waste Streams

The amount of contaminated soil which would require excavation has been estimated at 37,500 cubic feet (see Section 3.2.1). With limited information regarding the levels of contaminants in the back lot, the feasibility of excavation and removal, in-situ treatment, fixation and encapsulation, and land disposal can be determined. It is noted that screening and/or analyses of soil samples obtained in the field during soil excavation and removal procedures could be conducted. This information would enable more refined limits of soil excavation and removal required to be determined. This would, in turn, reduce the amount of soil to be removed and, consequently, remediation costs.

REPT4/tdg 10-5 11.0 Bibliography

Clement Associates, Inc., 1985. Chemical, physical and biological properties of compounds present at hazardous waste sites. Prepared for the U.S. Environmental Pro- tection Agency. Clement Associates, Inc., Arlington, VA

Science Applications International Corporation, 1985. Summary of available information related to the occurrence of vinyl chloride in groundwater as a transformation product of other volatile organic chemicals. Prepared for the U.S. Environmental Protection Agency. SAIC, McLean, VA.

U.S. Environmental Protection Agency, 1986. Addendum to the Health Assessment Document for Tetrachloroethylene (Perchloroethylene). Review Draft. EPA/600/8-82-005FA. Office of Health and Environmental Assessment, Washington, DC.

U.S. Environmental Protection Agency, 1986. Superfund Public Health Evaluation Manual. EPA 540/1-86/060. Office of Emergency and Remedial Response, Washington, DC.

U.S. Environmental Protection Agency, 1985. Health Assessment Document for Tetrachloroethylene (Perchloro- ethylene) . EPA/600/8-82/005F. Office of Health and Environmental Assessment, Washington, DC.

U.S. Environmental Protection Agency, 1985. Health Assessment Document for Trichloroethylene. EPA/600/8-82/006F. Office of Health and Environmental Assessment, Washington, DC.

U.S. Environmental Protection Agency, 1984. Health Effects Assessment for cis-1,2-Dichloroethylene. ECAO-CIN-H015. Environmental Criteria and Assessment Office, Cincinnati, OH.

U.S. Environmental Protection Agency, 1984. Health Effects Assessment for Vinyl Chloride. ECAO-CIN-H036. Environmental Criteria and Assessment Office, Cincinnati, OH.

REPT4/tdg 11-1 Andleman, J.B., S.M. Meyers and L.C. Wilder, 1986. Volatilization of trichloroethylene and chloroform from an experimental bath and shower system.

[Symms, K., 1986. Approximation of the inhalation exposure to volatile organic chemicals from showering with contaminated household water.] incomplete reference

Brown, H.S., D.R. Bishop and C.A. Rowan, 1984. The role of skin absorption as a route of exposure for volatile organic compounds (VOCs) in drinking water. American Journal of Public Health. 75(5): 479-484.

Minnesota Department of Health, 1986. Recommended Allowable Limits for Drinking Water. Prepared by MDOH, Section of Health Risk Assessment, Minneapolis, MN.

REPT4/tdg 11-2 APPENDIX A

BORING LOGS

REPT4/tdg PROJECT: Lsng Frairie PIRME if-.c. PRQJE:: NO.: cs7io:ioo: fORISBi 1 2A7E: 5,i Novesser '.98i FIELD JEOLJSIST: EDIAN

! SA*F. KG.I! 6L(U5/SU IN.! 5AHF. REC./ ; ^AT.nDIET.i,IL MM, : COLL? 1 SOIL SEECRIPM3N ! REKft^S i DEPTH (FT!; : En«F. LENGTH ite.T . i-'Ti •jSCS: I iliJSCS designation) [HNu reasing; color}!

! t5-'l'l i '! r I 17 i.Vt .1/1. ISD.i vc, very pcorly sorted, size a-ge 4'ct clay to ccbcies, : !Ss) CO] {7.EYR5/O

very .'£[.; B, SOKE c - vc scl. ird granules, ;en ! Peebles aid t sd., trace silt, : iSp* [0] {7.5VR5/0}

.6/1.5 liD.; a, s:se c, vc ana { sd. and granules trace »iit an: pe:bi£s 153) CO] £7.5Y«/C;

, 29-30.5 1 7/5/3 0/1.5 !

r 6/2/1 1.1/1.5 ve v ! ' Itop .9 E-u.i «-t, sons c s:., trace granules ! l:cse i i iSp) [03 J7.EISi/C} ; ; ' :hot. .3 ££.; vc, so?e c-» S3. and granules I : i t^ace j=s:le5, t ss. ana silt

1 "4-T5.5 i i/7/a 12058 ! N/fi !No

1.1/1.5 very ; grey !S3.; ^-«, saie c sd., trsce s:lt ano grarules, i loose : ! lenses st c-vc sd. Kith granules i i (Spi [0: I7.5YR6/0) !

c i-t 3'T-iO.:. r. B; 3 1.4/1.5 lease ! ' 'A - top 1.! SD.; a, soae 4*: sd.

• c - act .3 granules, =cae peables, tra:= c 3d.: ; i 'Spi [33 (7.5YS6/0} :

;Sd.; c, soje •ii+vc sd. a-o C'aiuies. ^s* ssbrles trace t sd. jr.3 silt : liffi [0] :7.;i^/0}

r r :tt;:r5s ara :r-t; : .j ::• seal PROJECT: Long Bra;rie IMLCCin PIRNIE INC. PROJECT KO.: 05710:4002 ELEVATIQN: DATE: 5,fc NavBiber l?2s FIELD 3EC'LJSI57; 3CIAN

EA!

At-45.; i !t/9/b 1.5/1.: «et ! lease ; grey !S2.j c, some «*v: j:. anc sra.Tjies, fen ;eto:es ! I i trace t sa. anc siit ; i : isci [c: :7.:Y«;3/<;:

30/li/ll ; ;eaiLi ; ' ;A - to; 1.4 site as a::ve : cense i ! (So! CO! :7.5YF.s/c; ! ! ' IB - tot .1 possicir till i ! iSo) [C] {T.SVW/OJ

27/12/15 i.;/i.j Isiae a* 11 H abcve I (Spl [0] {7 i 13 ! : 54-55.5 : 12/6/4 .5/1.5 Icsse :5D.; i-c, very poorly scrted. si:e rar;e trai .till-like i clay tc pecaie .but r:t ienoucn

/ ISO.1, «, sose c-v: • s:., TS i trace silt i i:i : t:; : PROJECT: Long Prairie : MLCCL* FInNIE INC. FSGJE'T \G.: '

i i .- i I . i i . i i ; SAW. vs.*. 3i.c«£./£H IN.; 5ftr:?. SEC./ i r.A'..",ci=T.t; SOIL :EI./ i C;LCR ; -jii. DESCRIPTION : ; DEPTH (FT/, ! 1.5 aS i ii.T. i?T. : iiisCs! i ' (JSE3 aesignaticn! ihNu valaEJ xHUNSEL. coicr; ; ! I ' . ' I i ' i"~7"T"I : ...... _»... . '." " ...... '; ...... ; ...... ;' ...... , ...... - ~ ...... ;' ! ls.5-15 : 4/S/7 i - .8 ! Met ', leass ! buff !toa .2 SD.; iive-e: f-e sd, little : si. i : ! ! • : ! trtce gra.TLies ar.-: silt ; ; ! ! ; i ! (Step! tO] (10YR3/3) ! ! ! ! ! ' :bot. .s SC.: i-c, trace i so. and granules I

, 2i.5-23 i 6/6/5 ! 1.2 ; ' ; iiiie br!52'.; r-c, sate f sd., trace silt arc granules ; I ; i : : ;tc buff; !SPi [0] UOYRE/2} ! I

! 31.5-33 ; 7/5/i ! 1.5 " * . ' :5ase as aocre. slightly sore v: so. !3riiier ', ! : ; : ! ' i iSF) 10] £iO:R&/2} inoticea ; i ! i : ; .' .a ver, !4| ; ; • : ; large : : 3s.5-3S ! 12/30/19 ! .7 : aeciun i;.ottiediSD.; v:. very ooeriv sorted, cram si:e rsige Icobbie :cie ! ! 1 : -:ense ; rrs? cla* to >2' cciioles iat *35' [0] C7

C '-40.5 . 9/21/12 , .4 . ; * ; ri isa.72 as aasve aut nose of tS saauier , ! : ; : ' : : , ccntairec 1/2" o* aari: siity f ;:. i ! I . 1 , : 1 ;=Psisc: [C] {7,5yR5/4: ! !

! 6 i ! ! , : ! ! ! , 40.5-42 ! 17/li/13 ; .9 : " ' ; ' ;sa»e as tain Ear: cf saiiple 5 aoc'.-e ! i ! ! ; ; ! : (a^'ssscl LCJ ^.SYRS/^) i I : 7 : i , : : i ; i : 4i-*5.: ', 27/24/12 ' 1.3 1 ' i tai ISC.; r-c, sa»s vc + f sd., vc sc. '.enss with !bct .3 has '. : . , i ! g-annies, trace silt Ichar.ge in ! ; ! : ! . i ! i:5) Ci] ClC^R5/2} Icolor : I ;!.:!! Ito It qrey ;

' «3.:-4j : 12/12/6 ! .£ ! ' 3 ; gr?y !EC.; :-vc, verv pccrlv sorted, si:e rang? ; ! ; , ! ; :':s clav to peiiies i : ! tSPsss:; Cu UOYR5/2: '• •

.9 ; " , ; •• itcp .5 saie as : : ; ! iSPss; [03 {lOV^/2; : !bc:. .4 si«8 a« a:ove cut sizes up t: cssdes

-:.e ;:i-.::r.rC •r.ri a :!.-50 T.x of c.:t.--:5 aro ;e-;or,;r.5 t: seal 'ule,

FfiSE: PROJECT: Lorg Prairie IWLCOLN FiRNIE INC. PROJECT NQ.; CE71J2iCQ2 ELEVATION: DflTE: 7 FIELD BECLC3IS*: SCIfcS

EA«P. NS.i! BLOiiE/SIl IN, SAHP. REC./ REflARKS DEFTH (FT)! 1.5 SS saucier M.T. iFTj ! H-sCS) (USCS issisnausn; [H^u vaije] {f-.-NsELL ccior)

li1 12/9/13 1.4 wet iW; trace or dissecinatec cranuies, raintiy ! dense grey ! Uye'ed, DC5=;t!iv varved ciavs, tec .4' car.; g^ev ;Ch; to] noYF-5/;}

53-54.5 . 5/15/12 1.4 Blue ICLAY; possibly varvea c.ays :rsy I iCH) [03 {1CYF.5/1J

1* ! ..5-56 10/L3/22 1.5 tlue :sa::e as aocve qrsy • \Ci: [03 C10YS5/1) FF.CJECT: Long Prairie f PIRME ;N:. PROJECT N3.::27icisC02 BSS1N3: 3 ELEVATION: DATE: 5 ;ycvemi>er 56 FIELD EEC.JGIST: S;:A\ i SA!".P. \3.i i SEFTH SFTI 1.5 £5 i «.T. (L-! : '/.sis cesigraticn) iK^ value] (HuNSELL csior} i

; 1 i 17-13.5 1/2/3 .5 very ! :ro«n ,SD.j c-vc, s:se IBDKSI sd. and granules, l:ttle .•fili/nat. loess i t so., trace silt ibounoa'y tO] ;iOYR4/3) cown

I*-:;. 5 3/17/15 1. ieo:u« ! ' I2A-TOF 1.0' sate as aaove • dense ', : (SPsi) 10] UOYR4/3} : ! rust/ I2E-BDT .5' ED.; vc, sote « sd. anc granules, i ! *butr ! ten peboles, cosoles aid • sd.. trace s:l: : ; : (SH [)] '. i 29-30.5 15/19/40 1.2 ! lite ;3fl-TDP .5 SD.; vc, soae c sc. and granules, 1 ?ron : trace c sd. i ; I5PI 10] ilOYRSM} :alter- 133-BDT .7 Buocal; SC.; silty i-t. sd. satrix Inati^q ', with granules, oeobles. cobbles * c'.av sis; ,crey*cr; iSPsel [C] {iO»ft5/4}

ifl+i .4-35.5 19/12/2- : lit? ;4K-TO? 1.3 SD.; i-c, trace • sd. a-d c-ranLiEs , ; :rev ; (SF) [02 {10VF:5/:: ; : I4E-B3-T .2 Very poorlv sortes clay t: 1.5° ; : g'sy : ccssiss, sain cotronert \z SI'.;poss:b:/ till, !5?sas:i 10] {10VR5/2; i

^6-37.5 s/24/2* i q-ey iTILL [03 (10YR3/1:

24/70/27 dense ITILL l=C5ql CO] {10YR5/1:

a:ar.3:',e: m;^ a ",:•'. 'u: o* :utt:r::

EDnJNb: 3 PROJEi7: Long Prune «ALCOLi PIRN IE IN:. PROJECT N3.: C371C2:CC2 EJRI'iS: Iv DATE: 14 Nave«jer s: FIELD EEILCGIcT: a^IAN

SACP. SG.i! SLohB/sIll IN.! EAWF. =E:./ DEPTH IFTii 11.5 Ss saifier; ii.T. (F7) ; iu'SCs) ..LBZ: :e5;qr,*tion. [H.Na value] ;1!.:NEEi.L color

.5-2.0 ; 39/42/<: .i dry dense !-D.; f-t, First 5s saioie SP.CKSO :'r:-g:nal sase : c- let. A Use or neivy jii :n; :e;cre ta- 1 :ov»r. First teot or natsnai rr::e", r:r = : : '*" titLjnous i : :=1 I-II :«; ;se:c^: H!«u val^j *rc- ; , S;BI ano cuttings] First value tres s= sifi:la : 2A-B i > 2-3.5 6/12/5 .9 loose I2P-TGP 1.0' sate as aaove but siigrtly carker ; ; :£*.sc: CO: ! ilE-t-T .2' F:li/ r.atural intertacs ! ; 5[.; t. sj«e i sd., trace siit ! [0: [0] i

7 ^ 3.5-5 7/S/B ; lite '£[.; '. =cje a sd., little c sc., trice silt ; cron ,. inc vc so. : (Srisoi [C3 :oi

4 5-6.: i/5/4 1.0 'Ea.iK as tscve ; 'Srsj! cc] :c]

a.:-: 7/4/4 iEaia a= accve ; !£!1aB) [!3 [C'J

4/4/5 1.2 e Inhitisr, isaie as aocve !nhit:sh : iyell3i< ; I5H [4] [03 !:or,es aay ; : : lhave been ! I bleached. I 5/4/6 1.2 very ;;r. 'ish iEJ. ; :., SDie f sd., iittis c sd., trice vc so. ITrace c» ! lease iyellcN : nd silt laacxe also ! 1 . 'Srls:: [ = ] [4] .at fis I i : ,29t-.

5/b/c .E daia loose ,5=-;e j; ajcve • iE-s:; Li3; [1-2:

£;:.55 •''•:' ::r;n: here =fci 3e:c'e ^LPEE!! c:::'1 cc:e :es::r.i;::r, His issiir.sc :r:r: -:ls hes : •.•'eaiatelv -.je: tcr »si; »!!• :rst3liat::r.. '•- 'e = ::-:s at reac •=:::: ir, »ork srei «ere ai«a/s i=S3 :rian i ;;.', i.sua"ily 0 l52:~E: '.;-. :"5 =;c::ents *av :s ::,c:cati«e s^ ':er:n PROJECT: Long Prairie NALCOLH PIRNIE INC. PROJECT NO.: OE71Q2£i02 BORING: 10 ELEVATICK: DATE: 14 sioveiter 86 FIEuu 5EOL2SIST: SCIfi*

.i! BLOW/SIX IN. SAMP. REC./ ! HAT. MIST. I SOIL JEM/ . C:L:K EC:L DESCRIPTION , REMARKS 1.5 SS stapler! M.T. (FT) (L'SCSI ' lUECE :esisnat:ci; [HNj value] (fL'NSELL cclc-) ! i 9A+B 1 12.5-14 ,' 5/4/6 1.4 daep very ,'yelioM ;?M-TDP .? 5D.; i, scie • sd., little : sd.. loose ! i trace vc sd. anc si it I : isCssi : ;5B-E:'T .5 ED.j t. scae i sd.. little c sd. I iro siit, liverec. *"iitish zanes :c«r = E ; ; ar.d ;:ssiBiy ilsached by 'PeriP ; l ISM) [Z20J I5i

10 ! 14-15.5 : 5/7/b «et ,H.TJtun.sane as ab:ve

11 ; ! 15.5-17 : 5/6/7 1.5 ihte !3C.; «, scie * + c sc,, little s:it, trace :tr. 'ish,r vc S3. and pei iyelicw i (Step) [4]

! 12A+B i. ! 17-18.5 1 6/6/0 1.5 i lite ifi*B; sane as above mth trace granules, ! broxn I double satpie U'er ! ISKsp) i4aDl [15". .rea::nc

; 13 i ! 18.5-20 ! 7/8/7 ' :ro^n isa/ie as aaove i ! ISHsc) I35CJ [25:

14 ! ,-11.5 ! 20/9/11 I lite ;S£.; •f-vf, sans silt ait! x 53., little : sd., dense ! grey : trace cranuies ! i (SMso) [2CQ]

.7 ! lite llSfrTGP .! sa»e as iccve Ibr.'isi! (S*!s!! [25] [20] i grev •

start :•• '.ra-siti;! zo;\s, e*fscti

L0*a/sii IN.: SA«?. ".=T ::L DEN/ 11.5 S5 :J5C5) ; iLSCE CEBicr.aticn.- IH'-u viiueJ {.IL-siELL c:::r; !

net '.Till: So.icy till. trir.s:ti;nil ;ro» :c*.aact 1 CliCIii Qli:«i;h tr lCS5S si'iV till l5'--«; [7C! [20]

16/21/13 tediui :tr.'ishisa^e as aaove sense • qrey ! (SH-Sdi -3C] [15: PROJECT: Long frairie MALCCill PIRNIE INC. PROJECT NO.: 0371G2AJ02 EORIK6: 11 ELECTION: OftTE: 3-4 Ncveitaer Ei FIELD 8EILG6IST: SCUM

! SA*P. NO. 4 i

7/5/4 1.2 dry .oose hti .5 TGF arcar.ic: r:cn organic hums brawn .7 EOT SI.; f-*, trace coarse, well scrtrc1

;Ftl [03 [7.5VR5/4J

12/10/12 i.: :ry teoiu« ! SD.; C-P si!., ioiie f sc., fen qraniies, :ra:e dense ! petbles, socr :eiding :ctl CO: (7.5Y*5/43

i.J-5 loose 5 TJ? saie as aaose iPtl CC3 {7.<-'R5,4} 7 ECT safe as eDove but t>riter, enc ot ircaiic n:n L.3cer ::ne

i 9-10.5 5/4/3 •oist I very 1 buff SD.; ^-c s:., cocerace scrtir.g : 1 '.cose ; nater taoie «; acttci of splitspaan !=:ssJ COJ (7.5'r((5/4J

11.M3 «et ,3 1C? Si.; silty f iSFsini [C3 {7.5YF5/i5 i ,9 EOT Sranules, ;r:cK fragients) EDte : sc., : trace «-f so. 1 ISP! [03 C7.SYR5/4> !

14-15.5 13/12/17 u!es, irc:k fragments!, sc?e c sa., little i i sd., trace f sd., aoor oeadir.g * sorting I (SFi [03 {7.5rR5/ii !

it.5-15 14/12/17 .9 as aaove bet -.0 visisle :e:d::; l;ri * D) \ ;>' '•. 'j t"',.'.ji^j.-! f' T-c / •.'

.7 TuP £[.; »c-s, ic«.e T =a., fact c'aruies .3 tIT BRflNijlEs - SD.; vc, sooe E-: EC..

30/3'. -^n o; cut:jr;s an: :ent:nte to =sa ic:ri>:ior.e:v ; i-e after ::n-g mas cr:ils:. »rsn :r:F.en i stes was PROJECT: i-or.g ?rair:e MAL:i3Lf! FIRHIE PROJECT Itf.: JS7102iOO' 3CRIN6: 11 ELEVATION: OATE: 3-4 Hcvesber Ei FIELD SEOLQG1S7: SCIftN

T ; 5A«p. NO.&! BL:*5/S!: IK.: SAKP. ^E:./ ; rA .rj!5T,i E;:L JEN/ 50:i. :E:CP.IPTi[Hi ?.E?*ASKS I ; DEP'H (FTi: 'I.: S3 saipieri *.T. iFT; . ,i;E2E: ces;:na;icn.' !*Si; valueJ -INiiNStl-L cclrr) ;

'i net : sec:ua . lite :;i\HNLi.ES + '.'C EO.; so;e «-c 5C., trace pesoiesi

ic ; 22-;:.; is ibsvs Es. FiaE.Es + ClsBLEE; sc:» t »c.. trace s:lt !3Fi [CJ i7.SYR5/4: :

11 ] '.£!.; .1. =c-.s c + s:., ts* ! face c;t::es ar.s siit

19/9/20 1.4 1 tediui ! ' :ToP .4 ED.: \', s:?2 silt i cense , i iSF! [03 {7.!VR;/4) ! : ;BOT 1.0 SI.; :-v:, scxe s:it ana f s:., : ! i trace gravies 1 ! ! isF! [03 '7.EVF5/4;

19/E/7 1.1 as a:ove

; 14 ; i "=-29.5 ! B/5/6 1.2 : lo:se ! ' I3C.; t-c. aas? qrar.jles a.io silt, 'last i ! ! trace psccies f?.c cofiole-: Ion

1.2 ! ledus i " 'EC.; -c, scae s-c sc. aio 'jraiii.es, ! dense Itop .3 i :e» :s:b!es ars s:it, t'ace cobbles !se*p:e or :* fioesssr

1.0 grsv ,sjje as j::ve ! .if) [•:] (7.:rR7/2;

EO-hS: 11 ftC-E: 2 s^ 4 PROJECT: Lane Prairie NflLCDLf! PIRNIE INC. PROJECT N3.: 067102iC-02 EuRINS: 11 ELEVATION: DATE: 3-4 Ncveioer 86 FIELD 6EJLCGIST: SCIflS

, 3JHP. N3.li BLOiiS/SIK IN.! SflHP. REC./ SCL DEM ! COLOR i 5DIL JE=C?.!PTICN ! 5E.1ARK3 DEPTr- (FT) il.5 SS sappier W.7, iFT) . iL'SCS ;es;gr,ati:n! [hSu vaiueJ :Ml:N:ELu color} I

<7 32.5-34 27/22/12 net crey !TD? .6 SB.: f-:, scie vc sd., fen graraias dense i ar,d f ss., trsce silt : I5fi tO! ;?.5YR7/2; :=OT .t GRftNULES * v'C SD.j so*e seablss. ! ten Derbies and a sd., trace * ss. silt

34-35.5 17/15/12 : 1.3 ' iSD.; «-c, 53*e r + vc sd., ^e* granules, too .3 : :race cooble : !E;-! to: ;7.:v!;7/2: :iii9 .'ILL: very -ire grained, trace q-a^u.es crey i iC.l [0] {7.5YP4/0) bot .5 ! 19 35.5-37 I2/17/15 , .E blue isar.e a; asove grey ! ,LU. iii i7.:'if\4/0i :o T7-3S.5 19/le-lS ! LI J isase as above ; iCL) [0] C7.5'^/Oi

! 21 ! 38.5-40 17/15/25 !saie as osove 1 :CL; [j: {7.5rR4/0!

;. -4i.5 4/6/5 isaie as above ! !CL: [C3 i 42-43.5 7/4/4 very grey isD.j c-vc, sciie a si. arid loose , is* ; sfl. anc silt, t'jce til:

: 43.E-45 J/4/C .5D.; t, scue f c sc., few vc sc. • silt trace series ar.fl till lenses ! i3:s».j [jj {7.5VR5''.;

.safe as a;ove 2ut Nitnaut tiii ie.ises

PPaE: 3 PSOJECT: Long Prune KALCOLW PIRNIE INC. PROJECT SD.: OB71026&C2 BORING: 11 ELEVATION; SATE: 3-4 Noveicer 36 FIELI EESL2GIST: SCIAN

I SM?, JiO.i 3LHS/SI1 JR.1, SAHP. RE:./ ; "aT.soiST.4! SDIL SEN/ COLDR 1 SOL KSCRl'TIM : 5EFTH (FT) 11.5 £E seisier: d.T. (F'i ! (UEZEJ : (LiC£ desionatiori LHNa vaiiie] {KUNSELL cclor}

! 2i ! A6.5-4B J9/27/13 Nri i aeiius i grsy iSD.; vc, s:ie ;-c sc. and granules, :r,se ! ; few t si. a-sc silt ! . : !SPs-,i :c: i7.5VR5/0)

16/17/15 !EI.; :-:. s:ae : 5:. leises witn I s:« silt,

;SD.; J-t, sose c so. «nj siit, trice crannies ! iSPsii" vC] {7.5YK5/C}

29 51-52.5 16/17/1B 1.0 ' .'TOP .6 SD.: f, trace i sa. ano silt iSFss! [0] ;7.5VR5;::) Igradi^g cs IrOT .4 SD.; s-c, sc« vc + i sa.. ! trace granules i i5Fs») [0] [7.5VS5/!;'} i S2.5-54 13/20/20 1 ISD.; :, soce s sc.. :-vc si, lenses with i trice qranul?5. c.3T.e silt

i 31 ! 57-53.5 :5/:7/;o , Isase as £0] (7.5YR5/

sl.5-c2.9 very i ',53DBi2 lost, chsnqe i^ cr::h?,g rssiste?:e tor :' : cense I I nste: at eO.5'

S * :; PROJECT: Lorq Pnir:e RftLCCLM PIRSIE INC. PRQJECT KG.: OS7102a002 50RIN3: 13 ELEVATION: DftTE: 12 homeer S6 FIELD 5ECL05I=T: SCIftN

! SAMP. NS.i EL3H3/EH IS. SAMP. REC./ : MT.ffilST.l! SCI;. DEN/ COLOR ; £J:L DESCRIPTION ; i DEPTH (FT) 1.5 £S saipier! *.T. !FT1 ! liJSCS) ! (liSCS eesigncticr.) [HNu value] {HL'NEELL color} ,'

! 1 ! 4-5.1 1/1/2 1.1 dry ygry lite ISO.; », scie f + c sd., httl; vc so., icose sro*n : trace granules (S^sp nith PT! C«] {10Y-M/3;

; s-io.s 2/1/2 net bat irc'«n ;£D.; c-§, SORB vc » f sc., iittle craniiies. i trace silt tro:en with PT; {10YR3/2)

3 4-15.5 ITQP .5 sase as above 30T .3 5RANLLE5 + VC 53.; s:»e * sc., ! little t sd., tracs silt (3cs«i C10YP4/3)

I 19-20.5 6/5/4 ISO.) i, sote i + c sd., lif.le /c 55., ; trace granules

Jft+B ! 24-25.I

12/10/12 br' ishiSD.', a, sc«e t * c sa., little vc sd. sense grey ! anfi 3ran;il?s 1 .SUSP) (I'MS/l;

/B/L&- l.l lo:se i s-c, ioue vc 5:., irice grannies * i ss. ,5F: ClO'-RS/l)

;»j f"Ju rsj:i-cs were -.31 t4K=n cue to extreae colt!. v?r;:9 teiis'ft-.'e ^a= ;ej:* :erc t«!f «irc cnii: t: Jin^s 1!". :L;:; to iins 45' ?r::2r,5 t:r:- ««< usec :c 'j"»rse:e sa.-sie ^rct solic 5c:on Easier. •icle rj; i;:rc:-=3 *:r ;;/50 in o* cuttings jnj tent:::te to seal naie. P-3E: PROJECT: Ion? Prairie MALCOLM PIRNIE INC. PROJECT NO.: 0571026:07 EOF. 1 No: 13 ELEVATION: LATE: 12 NCVEKBEs; at FIELD SEC.C3IST: KIM

! SAMP. NG.i BLOWS/SIX IN.! SANP. SEC./ i HflT. HOIST. i; 50L I EN.- i CQiIF, SCIL :E=:=I5TICN F.ENASK5 : ! DEPTH (FT/ 11.5 SS saiDier! il.T. i?Ti : il:C2! ;es!"atior,! irNu viluel ;

: 39-40.5 9/8/7 : wet tut 13053 i grey !E3.; a, soie t 55., little c-vc sc., i 4ro:en i ! . tries g'anj.es a->fl silt ii Mediately ; ' I iSFsii C ! f.'DR CCiB i ! : 10 ' 41.5-*: 8/6/5 ! : ! isaes a; acsve ClOIRS/li i 11 MS.5 6/7/3 1.1 isC.j «-i, little c sd., trace grarales

,3*53! -HOiS;. 1) i 12 i 46.5-46 B/7/? as asove bjt 10

! 13 ! 51.5-53 B/E/7 isase as asove but xitr trace pesoles i :S."s?; CCYRi/l;

; 14 ! 5i.5-59 6/5/7 5£ie a; acove

15 \5-b3 20/17/27 reaiut .sa.16 as a;ove :ut sl'.q ccarser dense :£;) {10YR5/1}

IE l27/20/?6 very as sa^ale i* csr.se

fe.-E: 2 C- I PflOJEC:: lo-g Prairie MlCCLM PIRNIE ISC. PROJECT N5.: 0371026002 BCRIN6: 14 ELEVATION: MTE: i: KCVE'EE^ 36 F:EL: SEOLCSIET: SCIAN i SW. KC.i IN.; E.W. F:EC./ ; I^T. *];;-. i; SDIi. DEN ! SIIL ZErCRIF'IDN ! DEPTH (FT; il.5 £S sassier; *.7. (FT; ! USCS: i (L'SCS cesicnaiiop.) W.j vjke] (MUN3ELL :oicr)

10/5/4 1.5 ary ! loose i darn i£D.; c, SEIS t + c si., little vt so., trace ! ; trc«n . vc £2. silt :rarules anc pebble; ! i I :S>!) [0] :iCYR4/3} i 9-1C.5 27/10/13 1 1.0 leoiu: i ' :TOP .5 saae as above ,settee dense itoa .5 : (SMI CO! (!OVR4/!i ..i1 wet ; DuH iBOT .5 SJ.j :-vc, SOM i ifl., little • S3., i loot .5 I trace qrjnu.es I i i (E^spi [c; cot^;:: ;

net I a ; bj^* !SD.; a-vc, saa? » is. and c'ar':ies. ': ! '• little ceDbies, tra:e :cc:ies us :: 2' ; I ! (aP! COj aOYF.5/3:

; 19-20.5 1.5 i brotin Isase as acove ; ! ISP! [0] CCYR5/3]

i 24-25.5 4/7/3 .£ loose i srown Iseae as aoove but coior :hance at sof.j !tap 1.2: i£P) CCJ {K-R5/3; changing :: ; grey ! (SF! [03 Ufl«.5/i; ibot .3 I s i i -30.5 3/4/5 very '. q^ey ISj.j vc, sose c-s sd. anc granules. Iccse ! ! trace t sd. and pebbles ; : isF) [0] a:

llnller telt a cr.aroe ir. anlling r2sister.ee lit 33.5', possibly iarqe cc^ale zore

tor t'- eery I " IED.: i. sane c-v: =:., httie t £C. + granules! dense ; i tracs siit ore 3es:le= ; ! ' .'5P! [C] {lOyp.5/1; :

very .$rr.'iS'-.lCLr.Y; a;i56Linate: •,; =:. lease i tirorvn 1 !3L; ti] (l>;i:,3/i;

-aie his s:;::cr.e: mtr. a i-jil': m\r. o» CL:t:ngs a:c :ept:^i'.e tc seal ^oie.

SWING: !' PHsE: 1 c; PROJECT: Long Prairie KALCCLM F1RNIE INC. PROJECT NC.: OS7:CI4C02 BORINB: 14 ELEVATION QftTE: 11 Sivesser afc FIELD EEO.DEIST: 5CIAN

i SAHP. '

• ' ; 11 , i 41-42.5 : 1/1/3 1.5 1 very ', arey !:D.: 4, scie n sc., little csd.. trace vc so. i loose ! i granules ana silt l^_. i ; i iSKsDi co] ;iovR4/i; ) i 1 !

' * ? , i*-45.5 ; 1/1/3 1.5 • •tie q'iniies i : < ant- s:it, layered »itn so?ev; •*• i sc. 1 , ', ! . lenses. Gne clay ball, acurcxisitei . t' , 1 ; , : isc.s;; co] aovs4/i; I i : ! ! 1 1 1 ; 13 ; 1 ( 1 • 49-50.5 : la/12/10 1.5 " ) eeaiue i " !saie as above 1 cerse ; ! !5Ns:) [i] ilJTf\4/l]

1 U | 1 ! 54-55 5 i 16/16/16 1.2 " ! " i ' isa»e as acov? :ut r; clay sr i si. leases i ! , ! .=ls;i [C] \lvirtil, I

: v^-sO 5 ; 27/36/52 i m *. i Sense ! " iA TC? .* si's as above ; | ! ! : !EMs;i L?] {10VR5/D ; [ ; i ' IB KID .-J tra^siticnal : i ; ! blue ;C 50* .4 T:_

; 1 = i 1 ( ' : 60.5-il ! 10o rar i" .5 B 1 ve-v ; " !TI.L i cense l ! iSCsci i\.l {;OVP,j/l} FRCJECT: Lcr.g Prune HftLCO'J! PIRNIE INC. P50JECT !<3.: C87202iOS2 SC-.ING: TsA ELEVATION: DATE: 1? Noveaier ae FIELD BE3LBSIST: SCIAH

: SAMP. NG.&i BLDKS/sII IN.! SW1P. P.EC./ ! HAT.HOIST.j; SGIi. DEN/ i : REMftRKS DEPTH (FT)! 13.5 5S saaoler! li.T. ("! ! iL'SCS) : il'ECS cessation) [HNj value] {MiSE:L ccior) ;

1 .5-2 i9/3/e 1.2 dry ! red:us FILL; 0-2" asorait, 2'-6" corcrste, t'-2' fill • dense 'FILL! iC-2 i*}

very .ayerec scctlsa: il! loose (FILL) i.4J

1/1/2 no sacple

4 5-t.5 1..) 5D.; n-f, scue c-vc 50. in: sil:

4/5/7 l.j SD.j s, soiie t + c 5Q., httie silt '(SO tl3e>]

6 6-9.5 5/5/B sane as Joove (ad) C70:

5/7/7 1.3 sate as ajove

.1-12.5 I 2/2/: 1.2 sans as above :SM) [60]

"? 12.5-14 sane as above

;2F;Nj: i:" PROJECT: Lorg Prairie MALCOlfl PIRNIE INC. PROJECT NO.: 037!C2i002 I-ORING: 12 = TBB ELEVhTiCN: £ATE: 17 Novelise' 56 FIELD atlLCSIST: SCIAN

I SflKP. NO. I.! ELCsS/EII IN.i SAflP. SEC./ ! W.ICIs EjIL DEN/ I COI.OR ! REKARKS 1 lEfTri (FT); !1.5 SS sanalsr, «.T. iF7 tUECE; i ; L;3CS iesisna ::^' iHNu vaiu»]ttUNSEL Lcolor )

0-1.5 , 4/5.'5 dry ! very ! cark :to;ssil I lease ; bre«n I iPT) C03 '.»)

1 "I 5/7/li Ic3ss ! iite IE2.; vc. setiiwn: s::e rings fro» s:lt : :ro»n . tj :caoie i : :spsai c:: i 3-4.S i 23/2?/36 ' Isaie £s taove aensa ! (SF'ss; [CO

4 4.5-b iGrc»e! zcne, sa.ipie froa cattiros

1 6-6.25 ! ICO for -:1 very , saie as above but mh a latrn of granules der.se ; an: :-vc so., sots * sd., little f sd. ! (G«! 1C]

, a-6.25 i ICC for 31 ! sronn iTILL [:3 i 9-10.5 ! 27/22/30 teems ; " liaie cs atcve cerise , , iSLspi Ivl

! — • E I 1 LO.5-12 1 10/12/17 ' I ' Isace as a&ove

12/10/12 1.5 ' ' Isa;e a; a&cve itcs .5 ; '.iZsj) [

i i

{*; "ii-.seli :cicr chart :es:gr.ati:ns r.ot Hole aian::-;ed *:*.• a 50/50 ju o» :ut::pgs arc Dentc.iits t:

BDRINS: 12 = T:b rrairie RfilCCL« PIRKIE INC. [ATE: 19 \oveSDer 36 IiLJ £EO;.;5I5T: 5CI-N

! SA."r. VJ.i, IN.: SAHP. RE:./ . ".r.KjisT.i, = :. :£?•/ : COLDS i ; DEPTH (FTi! il.5 SS sa«pier; H.T. SF'i ; 1 (UEC; C55i:?at:Bn) irvj value:

: .5-:.0 12/1C/7 dry iODSS :*3

5/4/3 verv iocse ;FILL

4/4/4 !F!LL ! iFILLS i'.ts .E" .4 Kite natural s?G'isants SD.; t-i, so« c-vc =•:., little silt I .5!*!

! 5-b.5 i 4/5/7 .4 loose saie as above l£H)

S.5-B 5/i/4 1.2 SO., f, scae .1 sd. arc sii:, t'ace : sfl.

1.1 ve-y i brown as iccse

: 9.5-11 5,'5/f ! ' iTOP .6 site as above i 1 1BGT .4 sase as a:o'/e but «itn SB»B Np.it:sn 1 scnec layers. Dvertl: saicie Keli layered;

1.3 as iacv

5 ! 1.1 Isaae «s aiove

e ic reaa;:i$. ::lcr :r,art = 5:3-82.

r-:E: 1 C* APPENDIX B

MONITORING WELL CONSTRUCTION DATA

REPT4/tdg Stratlgraphlc Depth of Column Monitoring Well WELL SITE ABC Dates of Installation Well A FEE 8. 84 10 — Well B NOV 20. Be 0 Well C

20 — Elevation (feet above. msl)

30 — Well A (TOO 0 Well B (TOO 1296.24 Well C (TOO N/A 40 — Remarks:

50 —

60 —

70 — KEY Out wash Sand 80 — Till (Sand, Clay, Gravel)

Screened Interval 0 of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

Long Prairie, Minn PIRN1E Stratigraphlc Depth of Column Monitoring Well WELL SITE ABC Dates of Installation Well A FEB 7> 84 Well B FEB 9, 84 Well C NOV 14, 86

20 — 0 Elevation (feet above. msl)

30 — Well A (TOO 1302.46 0 Well B (TOO 1302.31 Well C (TOO 1302.22 40 — Remarks: 50 — ^ 0

60 —

70 — KEY Outwash Sand 80 — Till (Sand, Clay, Gravel) Screened Interval D of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

Long Prairie, Minn PIRME Stratlgraphlc Depth of Column Monitoring Well WELL SITE ABC Dates of Installation

FEB 14 84 10 — Well A r Well B NOV 18-19. 86 Well C 20 — D Elevation (feet above. msl)

1304.27 30 - Well A (TOG) 0 Well B (TOO 1303.10 Well C (TOO N/A 40 — Remarks:

' 50 -

60 —

70 — KEY Outwash Sand 80 — Till (Sand, Clay, Gravel)

Screened Interval D of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

MALCOLM Long Prairie, Minn PIRNIE Stratigraphlc Depth of Column Monitoring Well WELL SITE ABC Dates of Installation

Well A FEB 14, 84 10 — Well B FEB 8. 94 0 Well C FEB a, S4

20 — Elevation (feet above.msl)

30 — Well A (TOO 1296.51 Well B (TOG) 1296.21 D Well C (TOG) 1296.91 40 — D Remarks:

50 —

60 —

70 — KEY Outwash Sand 80 — Till (Sand, Clay, Gravel) Screened Interval D of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

MALCOLM Long Prairie, Minn PIRNIE Stratlgraphlc Depth of Column Monitoring Well WELL SITE ABC Dates of Installation Well A FEB 9. 84 10 -J Well B FEB 11, 84 Well C N/A 20 -H Elevation (feet above.msl)

Well A (TOO 1289.98 30 H Well B (TOO 1290.03 Well C (TOO 40 H Remarks:

so H

60 —

70 -4 KEY Outwash Sand 80 H Till (Sand, Clay, Gravel)

Screened Interval 0 of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

\1A1£OLM Long Prairie, Minn PIRME Stratlgraphic Depth of Column Monitoring Well WELL SITE ABC Dates of Installation Weil A FEB 14' 84 10 -J Well B FEB 13, 84 Well C FEB 12' 84

20 H Elevation (feet above.msl)

Well A (TOO 1297.49 30 — Well B (TOG) 1297.52 Well C (TOO 1297.99

40 H Remarks:

50 H

60 H

70 H KEY Outwash Sand 80 - Till (Sand, Clay, Gravel) Screened Interval D of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

Long Prairie, Minn P1RNIE Stratlgraphlc Depth of Column Monitoring Well WELL SITE ABC Dates of Installation Well A FEB 8, 84 10 -4 Well B ABANDONED Well C N/A 20 —i Elevation (feet above.msl)

30 —i Well A (TOO 1290.24 Well B (TOO ABANDONED Well C (TOG) N/A 40 H Remarks:

50 —1

60 —

70 H KEY Outwash Sand 80 — Till (Sand, Clay, Gravel)

Screened Interval D of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

MAUGOLM Long Prairie, Minn PIRN1E Stratlgraphlc Depth of Column Monitoring Well WELL SITE ABC Dates of Installation

Well A FEB 13' 84 10 -4 Well B N/A Well C N/A

20 —{ Elevation (feet above.msl)

Well A (TOO 1305.25 30 H Well B (TOG) Well C (TOO 40 H Remarks:

50 H

60 —i

70 H KEY Outwash Sand 80 -\ Till (Sand, Clay, Gravel) Screened Interval D of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

Long Prairie, Minn PIRMH Stratlgraphlc Depth of Column Monitoring Well WELL SITE 10 ABC Dates of Installation

NOV 14 86 10 -4 Well A ' Well B Well C 20 -4 Elevation (feet above, msl)

1304.19 30 H Well A (TOO Well B (TOO N/A Well C (TOO N/A 40 H Remarks:

50 H

60 H

70 H KEY Out wash Sand 80 H Till (Sand, Clay, Gravel) Screened Interval D of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

MAUCOLM Long Prairie, Minn PIRNIE Stratlgraphlc Depth of 11 Column Monitoring Well WELL SITE ABC Dates of Installation

Well A N/A 10 -J Well B N/A Well C NOV 19t 86

20 -H Elevation (feet above.rnsl)

N/A 30 —t Well A (TOO . Well B (TOO . N/A '.o' Well C (TOO -299.54 '•'•*• 40 -4 Remarks :

50 —f

60 —4

70 -J KEY Out wash Sand 80 H Till (Sand, Clay, Gravel)

Screened Interval D of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

MALCOLM Long Prairie, Minn PIRME Stratlgraphlc Depth of Column Monitoring Well WELL SITE ABC Dates of Installation

10 -I Well A Well B N./A Well C NOV :s- 20 —J Elevation (feet above, rnsl)

30 —\ Well A (TOO Weil B (TOG) N/A Well C (TOO 1295.68 40 H Remarks :

50 H

60 —|

70 H KEY Out wash Sand 80 H Till (Sand, Clay, Gravel)

Screened Interval 0 of Monitoring Well

MONITORING WELL CONSTRUCTION DATA

MA1£O_M Long Prairie, Minn PIRME Stratigraphic Depth of Column Monitoring Well WELL SITE ABC Dates of Installation

Well A 10 — Well B ;:ov 13, 36 Well C ;:cv 17, 36

20 — 0 Elevation (feet a b o v e m s 1) Well A (TOO _ 30 — Well B (TOO 1:97.9 Well C (TOO 40 — Remarks : 50 — D

60 —

70 -i KEY Out wash Sand 80 — Till (Sand, Clay, Grave!)

Screened Interval D of Monitoring Well

MONITORING WELL CONSTRUCTION DATA MALCOLM Long Prairie, S'inn P1RME APPENDIX C

PUMP TEST DRAWDOWN AND RECOVERY DATA

REPT4/tdg PUMPING TEST - DRAWDOWN DATA

PROJECTi LONG PRAIRIE FILE NO.i 08/1026012 LOCATION: MINN WELL NU.: 4B DATUM POINT: TOC ELKV. OF DATUM POINT: 1296.21 PUMPING RATE* 222 USGPM STATIC WATER LEVEL: 10.86 FT AQUIFER THICKNESS: 60 FT R - 285 FT FROM MW4 CONDITIONS: UNCONFINEl) SCREEN INTERVAL: 1262.92 FT TO '72 FT

TIME ELAPSED WATER ! DRAWDOWN CORKtCTED

13 ft 4 0.00 10.860 0.000 0 . OOO 222. OOOO 13 9 10 9.00 10.860 0.000 0 . OOO 222.0000 13 10 10 69.00 10.860 o.ooo 0.000 222.000.0 r.r 11 10 1 29 . 00 10.870 0.010 O.010 222.0000 13 12 10 189.00 10.870 0.010 0.010 222. uOOO 'f 13 1 •Ji 10 249.00 10.910 o.oso 0 . 050 222.0000 13 14 10 309.00 10.920 O.O60 0.060 222 . OOOO 13 15 10 369.00 10.930 O.070 0.070 222 . UOOO 13 16 10 429.00 10.96O 0 . 1 00 0. 1OO 222. OOOO 13 17 10 489.00 10.9X0 0. 110 0 . 110 222 . OOOO 13 IB 10 54V . OO 10.980 O. 120 0. 120 222.0000 13 19 10 609 . OO 10.980 0. 120 0 . 1 20 222.0000 13 20 10 669.00 1 0 . 99O O. 13O O. 130 221'. 0<>00 15 71 10 729.00 1 O . 99O O. 1.3O O. 13O 222 . OuOO 14 2 10 1029.00 1 1 . 020 0. 16O 0. 16O 2'2k'.OOOO 14 7 10 1 329 . 00 1 1 . 060 0.200 0.2OO 222 . OOOO 14 1? 10 1629.00 1 1 . O60 0.200 0.200 222 . OOOO 14 17 10 1929.00 11 . 10O 0.240 O. 240 222.0000 r?"} 14 *•'-«. 10 2229.00 1 1 . 1 30 0.270 0.269 222.0000 IS 0 10 1 2349.00 1 1 . 1 50 ! 0 . 290 0.289 222 . 0000 VALUE UStD 22^.0000

MALCOLM PIRN1L PUMP[NG TEST ANALYSIS STRAIGHT LINE APWOXtM^^^ 0 .561 f4o^ 17 ;-.isi'. 6 -<. *-£ It- *1 * (. 1 ^ \ ^ "\ .2 w .

\ \

P A \ it Z \ ao s

1 10 100 1000 10000 (T) TIME SINCE PUMPING STARTED (MINUTES)

PROJECT- LONG PRAIRIE WELL NO.: 4B ' AS- FILE: 087 10260 12 Q» 222 USGPM LOCATION: MINN S.W.L.- 10.86 FT S= MALCOLM PIRNIE | FIGURE 1 PUMPING TEST - DRAWDOWN I>A I A

PROJECT: LONG PRAIRIE FILE NO. I QB7K>1'6012 LOCATION: MINN WELL NO.i 4C DATUM POINT: TOC ELEV. OF DATUM POINT: 1296.91 FT PUMPING RATE: 222 USBPM STATIC WATER LEVfcL: 11.58 F-'T AQUIFER THICKNESS: 6O FT R - 285 FT FROM MW4 CONDITIONS: UNCONFINED SCREEN INTERVAL! 1252.78 FT TO 4B.70 fT

TIME ELAPSED WATER ! DRAWDOWN I CUKRtC 1 ED (Q) TIME LEVEL i I DRAWDOWN

DY HR MN t (MIN> (ft— ) :1 * ——. — i( —B ' — (ft>. (USGPn)

13 9 1 0.00 11.560 1 0.000 ! O.OOU 222. OOOO 13 50 49.00 11.600 1 0.020 1 0.020 1'22.0000 13 11 50 1 69 . 00 11.620 ! O.040 1 0.040 222 . OOOP 13 13 50 289.00 11.650 ! 0.070 ! O.O70 222.0000 13 15 50 4O9.00 11.670 1 O.09O ! O.O90

VALUE USF.D 1 222. OOOO

MALCULM P1RNIE AS-

PUMP ING TEST ANALYSIS STRAIGHT LINE APPROXIMAJION METHOD 0 ' * N

X K AS- t .40C i S X 80 » 13 1 i x, t i s .2 S*H * * s/S%f

^^ \ s P1 1 •4 ~ \ z \ 0 S a s, 3: s i .5 en

1 L 10 100 1000 10000 (T) TIME SINCE PUMPING STARTED (MINUTES)

PROJECT: LONG PRAIRIE WELL NO.: 4C ' AS=« FILE: 0871026012 Q= 222 USGPM LOCATION: MINN S.H.L.= 11. 58 FT MAI COI M PTRNTF FIGURE 1 PUMPING TfcST - DRAWDOWN DATA

PRDJTCT: LONG F 1 Lfe NCJ. : 0871026O12 LOCATION: MUNICIPAL WELL 4 WELL NO.I 4 DAIUM PUINTJ TOC ELEV. OF DATUM POINT: J297.4B f-'T PUMPING RATE: 222 USGPM STATIC WATEK Lt.VE-L: 12.66 AQUIFER THICKNESS: 60 H = KKOM CONDITIONS: UNCONFINED SCRE:I-:N INTERVAL: 34 FT TO 53 FT

TIME ELAPSED WATER DRAWDOUN CORRtCltD ',U) TIME LEVEL DRAWDOWN

DY MR MN t (MIN) (ft) 5 (ft) « ' (it) (USLHKM) _ « . , 13 9 1 0.00 1 2 . 660 0 . OOO O . OOO 222.000O 13 9 2 1 . 00 27.080 14.42O 1^.687 222. OOOO 13 9 •^f 2.00 27 . 630 14.9/0 13.1 02 222.0000 13 9 4 3.00 27.670 15.O1O 13.1 33 222. OOO.O 13 9 5 4 . 00 27 . 690 1 5 . O3O 13. 147 2V2 . UOOU i ; 9 6 5.OO 27. 70O 15.040 13. 155 222. OOOO 13 9 8 7 . 00 27.710 15.050 13. 162 222. OOOO 13 9 ^-t 8.00 27.720 15.060 13. 170 222. OOOO 13 9 10 9.00 27 . 730 15.070 13. 177 222. OOOO 13 9 11 10.00 27.730 15.070 13. 177 222 . OOOO 13 9 21 20.0O 27.760 15.1 OO 13.200 i'22.0000 13 9 31 30.00 27.010 15. ISO 13.257 22V.ouoo 13 9 41 40. OO 27.840 15. 1BO 13.260 222. OOOO 13 9 51 50. OO 27.B6O la.^oo 13.275 222. OOOO 1 2. 1O 1 60.00 27.890 15.23O 1J..297 222. OOOO 13 10 21 80 . OO 27 . 920 15.260 13. J1V 2^2.0000 13 10 41 1 OO . OO 27.940 15.2BO 13.334 222. uooo 13 1 1 1 120.00 27.980 13. i^O 13.364 2£;2.00OO 13 11 21 140.OO 28 . 020 15.360 13.394 222 . OOOO 13 11 41 160.0O 28 . 060 15.400 13.424 222. OOOO 1 .3 12 41 220.0O 28. 130 15.470 13.476 222. OOOu i.."> 1 3 41 280. 00 28. 19O 15.530 13.52O 222.0000 i ::-. 14 41 340.00 28.240 1 5 . 58O 13.357 222. OOOO 13 15 41 400. OO 23.300 15.640 13.60-,' 222 . OOOO 13 16 41 460.00 28.340 15.680 13.631 222. oOOO 14 2 45 1064.00 28.830 16. 17O 1*. V91 222. OOOO 34 12 45 1664.00 29.04O 16. 38O 14. 144 222. OOOO 14 22 45 2264.00 29. 170 16.510 14.239 2 2 2. OOOO 15 EH 45 2864 . OO 29.280 16.620 14.318 222."0«X) If. IB 45 1 3464.00 29.3130 1 16.720 1 4 . 390 22.7.. OOOO VALUt. USED 22 2. OOOO

. CULM fJlttNIE PUMP]CN6 TEST ANALYSIS STRAIGHT LINE APPROXIMATION METHOD 0

E a z Q a •«* S 12

1 , 1 AS= ( .491 —« <^*m ffm H 11 1 j • i S! M — — f IHt-JLJlJL t Jt =s !• ••• • 16 w— • ^Hm, rTHj M

20, . 10 100 1000 10000 (T) TIME SINCE PUMPING STARTED (MINUTES]

PROJECT: LONG WELL NO.: 4 AS- 0.499 FT FILE 0871026012 Q~ 222 USGPH T» 117361 US6PD/FT LOCATION: MUNICIPAL WELL 4 S.W.L.= 12.66 S= MALCOLM PIRNIE FIGURE 1 1UU

K < •X « X ):• \\\ \ ! \ \ ;«** * * K- -X 10 (S ) DRAWDOW N (F T

••• • *-» 1 3 0 100 1000 10000 f HI TIME SINCE PUMPING STARTED (MINUTES) PROJECT LONG FILE 08710260 1 PUMPINB TEST ANALYSIS LOCATION MUNICIPAL HELL A WELL No. 4 . | TYPE CURVE SOLUTION MALCOLM PIRNIE | FIGURE 2 PUMPING TEST •• DRAWDOWN DATA

PROJECT: LONG PRAIRIE FILE NO. : OB/102601--: LUUAI1UN: MUNICIPAL WELL WELL NO. I 5 ^p 3(, DATUM POINT: TOC ELEV. OK DATUM POINT: 129~lr+e FT PUMPING RATE: 222 USGPM STATIC WATER LEVEL: 13.21 AQUIFER THICKNtSS: 60 FT R = 50 FT FROM MW4 CONDI T IQNS: UNCONFI NI£D SURfcfcN INTERVALi 41 KI 1 O t.6 FT

i irifc ELAPSED WATER DRAWDOWN CORRECTED (Q) TIME LEVEL DRAWDOWN

1 "" """" "~ "* l)Y HK MN t (MIN) (ft) e <-ft) S' (ft) (USBPM)

13 9 1 O.OO 13.21O O.OOO O.OOO 222.O'X>U 1.;. iy 2 1 . OO 13.61O O.4OO 0 . 399 222.OOOO 13 9 3 2 . OO 13. 750 O.54O O.&J.8 222.OOOO 13 «y 4 3 . OO 13.780 0.570 0.567 ! 222.OOOO 13 9 5 4 . OO 13.790 0. SBO 0.577 222.OOOt> 13 9 6 5.00 1 3 . 8OO 0.590 0.587 ; 2 22.0000 13 Q 7 6.00 13.810 0.600 0.597 2 22.OOOO 13 9 8 7.00 13.82O 0.610 0.6O7 222.0000 13 V 10 9.OO 13.83O O.620 0 . 6 1 7 222.OOOO 13 9 41 40 . OO 13.84O O, 630 0.627 222 . OOOO 13 9 51 3O . OO 13.870 O.66O O.6ti6 222.0000 13 10 1 60 . 00 13.890 0 . 680 O.676 222.0000 13 1O 21 SO . 00 13.92O 0.710 0.706 222 . OOOO !.:• 10 42 1 O 1 . OO 13.950 0.740 0.735 222.0000 13 11 2 121.00 13.V/0 0.76O 0.755 222. OOOO 1 3 1 1 22 141.00 1 3 . 99O O. /80 0.775 222. OOOO 1 i 11 42 161.0O 1 4 . OOO 0. 790 0.785 222. OOOO l,i 12 42 221.00 14.O3O 0.820 O.814 222.0000 13 13 42 281.00 14.070 O.860 0.854 222. <->W<.> 1,!. 14 42 341.00 14.O90 O.880 O.874 2 2 2. OOOO 13 15 42 401.0O 14. 1OO 0.890 0 . 883 222. OOOO 13 t6 42 46 1 . 00 14. 110 0 . 900 0.893 222. OOOO 14 11' 45 1664.OO 14.6/O 1 . 46O 1 . 442 222.0000 14 22 45 2264.00 14. 750 1 . 540 1.520 222.0000 15 8 45 2864.00 14.810 1 . 600 1.579 222. OOOO Ib IB 45 3464. OO 14.860 1.650 ! 1.627 222. OOOO VALUE USED 222. OOOO

MALCOLM KIRNIE PUMP][N6 TEST ANALYSIS STRAIGHT LINE APPROXIMATION METHOD 0

3f* A3A QJ™I It • t. J* L « >i s T-230. 47 tm. 2! 7 i^1 1 . "**». E B It x^ z ^^ - *» ^ o a •*t A r* . f - Sl.2 a^"" i, .rjn 33/ T= 9BJ 22 >.o«; 55 V • X l.B *s X X s k \ x 2 ^ L 10 100 1000 10000 (Tl TIME SINCE PUMPING STARTED (MINUTES)

PROJECT: LONG PRAIRIE WELL NO.: 5 AS= FILE: 087102B012 Q= 222 USGPM T= LOCATION: MUNICIPAL WELL 5 S.W.L.= 13-21 s- MAI rni M PTPMTP 1 CTCIIDC K 1UU

>— u_ 2 ^ o o z < or o x * X 03 * 1 w • «<* X * 1 . , , • f ^

1 - - _i - L ; 0 100 100(3 10000 T TIME SINCE PIUPING STAHTFD fMrNLlTFS) PROJECT LON6 PRAIRIE FILE 06710260 1 PUMPING TEST ANALYSIS LOCATION MUNICIPAL HELL 5 HELL No. 5 | TYPE CURVE SOLUTION MALCOLM PIRNIE FIGURE 2 PUMPING TEST - DRAWDOWN DA I A

PROJECT: LONG PRAIRIE FILE NO. i 0871026001k LOCATION: MINN WELL NO.: 13 DATUM POINT: TOC ELEV. OF DATUM PD1N1t 1295.68 FT PUMPING RATE: 222 USBPM STATIC WATEK LtVELi KJ.4B FT AQUIFER THICKNESS: 60 FT R - 105 FT FT FROM MW4 CONDITIONS: UNCONFINED SCREEN INTEKVALt 1243.82 FT TO 58.82 FT

TIME ELAPSED ! WATER i DRAWDOWN CORRECTED (Q) _... _____TIM_E !i _ LEVE___.,„L „1 t __ _ DRAWDOWN i —..••.- j — — — - - — DY HR MN t (MIN) ! (ft) ! 5 • ' (ft) (USQPM)

13 9 1 0.00 ! 10.480 ! 0.000 o.ooo 222.00OO 1 3 9 1O 9.00 ! 10.700 I 0.220 O.I' 20 222.OOOO 13 9 25 24.00 t 10.780 ! 0.300 0.29V 222.OUO.O 13 9 40 39.00 i lo.aoo : 0.320 0 . i 1 V 222.0000 13 9 55 54.00 ! 10.620 ! O.340 O.339 22*'. WOO 13 10 10 69.00 1 1O.Q30 1 0.35O 0.349 222.0000 13 10 25 84.00 ! 1O.85O 1 O.370 O. 369 222.OOOO 13 11 25 144.00 ! 10.880 i 0.4OO 0.399 222.0000 13 12 25 204.00 ! 10.920 1 0.440 0.438 222.OOOO 13 13 25 264.00 1 10.96O ! 0.480 0 . 4 /U 222.0000 13 14 25 324.00 ! IP. 980 1 1.500 1.4B1 2I'^.OOOO 13 15 25 384.00 i 11.020 ! 0.54O 0.538 222.OOOO 13 17 25 504.00 ! 11.060 1 O.580 0.577 222.O0 13 19 2ii 624. OO 1 11.1OO ! O.62O 0 . 6 1 7 222. OOOO 14 O 25 924.00 i 11.180 1 0.700 O.696 2*'-.'.OOOO 14 5 25 1224.00 ! 11.220 I 0.740 O.735 ii2-'.ou0u 14 10 25 1524.00 1 11.300 ! 0.82O 0.fcJ14 222. OOOO 14 15 25 1824.00 ! 11.320 ! 0.840 0.834 •JI^.OOOM 14 20 25 2124.00 ! 11.350 ! 0.870 O.B64 22 2. OOOO 15 1 25 2424.00 ! 11.390 ! O.910 0.903 •^'2'2, OOOO 15 6 25 2724. OO ! 11.400 ! 0.920 O.913 222. OOOO

VALUfc Ubhl 222.0000

MALCOLM PIKNIfc PUMPING TEST ANALYSIS STRAIGHT LINE APPROXIMATION METHOD 0 AS^j[^2« Qonj ft _ — -. -* —i -^-». M *. 4 • .4 * 1C t

* , AS« Q ^46) Is S T-125C 35 I*. D7 X 7 S E 8 JT^ s* N o •v. 0 ^ v •N s St. 2 to

* 1.6

2 L 10 100 1000 10000 (Tl TIME SINCE PUMPINB STARTED (MINUTES)

PROJECT: LQNfi PRAIRIE HELL NO.: 13' AS= FILE: OB710260012 Q» 222 USGPM LOCATION: MINN S.W.L.* 10. 4B FT MAI COI M PTRNTF FIBURE 1 PUMPINO TEST - DRAWDOWN DATA

PRUJfc.L'1: LONLJ PKAlKJf. F1Lfc NU.i OB71026012 LOCATION: MINN WELL NU.I 14C DATUM POINTi fUC bLb.V. Uh DATUM PUlNIz 12V7.H3 PUMPiNb KAIfc: 222 USGiPM STATIC WATER LEVELl 12.59 FT AQUIFER THICKNESS: 6O FT R «= 216 FT FROM MW4 CONDITIONS: UNCONFINED SCREEN INTERVAL I 1245.99 FT TO 4O.9V M

1 II ME 1 ELAPSED ! WATER ! DRAWDOWN ! CORRECTED! (0) ! 1 TIME 1 LEVEL 1 t DRAWDOWN : 1 * i -*-" i DY HR MN ! t (MIN) 1 (•ft) ! B (ft) ! «' (ft) (USSPM)

— — m — ' 13 9 1 ! O.OO ! 12.590 t O.OOO I O.OOO 222. OOOO : 13 V IO I 9.OO t 12.610 1 O.020 ! 0.020 222. OOOO i 13 10 10 : 69. OO ! 12.64O 1 O.05O 1 O.OSO 222. OOOO ! 13 11 IO 1 129.OO ! 1 2 . 660 I 0.070 ! O.070 222. OOOO 1 13 12 10 ! 189.00 ! 12.670 ! O.OBO : o.oeo 222.0000 ! 13 13 IO 1 2 49.0O 1 12.69O i 0. 1OO ! O. 1OO 222. OOOO ; 13 14 10 ! 3O9 . OO ! 12.710 ! 0. 120 ! O.120 222. OOOO i 13 15 10 1 369 . 00 ! 12.720 i 0. 130 1 O. 1^.0 222.0000 I 13 16 10 ! 429. OO ! 12.730 ! 0. 140 1 O.140 2 22. OOOO ! 13 17 IO 1 489 . 00 I 12. 7 SO ! 0. 160 ! O. 16O 222. OOOO ! 13 IB 10 1 549.00 ! 12.76O ! 0. 17O i O.l/O 222.0000 ! 13 19 10 1 609. OO 1 12. 770 ! 0. 1BO 1 0.180 222. OOOO ! 13 2O IO ! 669.00 ! 12.780 ! 0.190 I 0. 190 222 . OOOO i 13 21 10 I 729.OO ! 12.79O ! O.2OO 1 0.2OO 2 2 2. OOOO ! 13 22 IO 1 789. OO 1 12. BOO 1 0.210 1 0.210 222.0000 ! 13 23 10 ! 849.00 1 12.810 1 0.220 : 0.220 222.OOOO ! 14 0 10 ! 9O9.0O ! 12.820 ! O.23O ! 0.23O 222.0000 ; 14 1 10 t 969.00 I 12.830 ! O.24O ! O.24O 2 22. OOOO ! 14 2 10 ! 1O29.OO ! 12.B40 ', 0.250 1 O.249 222.UOOO : 14 4 IO 1 11 49.OO 1 12.850 1 0 . 260! O.259 222. OOOO ! 14 9 10 1 1449.00 ! 12.99O ! O. 4OO 1 0.^.99 222.0000 : 14 14 10 1 1749.00 ! 13.120 I 0 . 5 JOi O.b2B 2^2.OOOO ! 14 19 10 1 2O4V.OO t li.ISO ! O.560 ! O.557 222.0000 I 15 O 10 ! 2 349.0O 1 1,5. 1WO ! 0.590 0.5Q7 222 . OOOO 1 VALUE USED; 222.0000 :

MALLMJLII PIRN IE PUMP][NG TEST ANALYSIS STRAIGHT ^^^^lU^I^ 10907 0 \ i t L^L 1 N, • ^ ^

q T-ii25. 2JL 02 -i L*-- -A Ja • ! Z i o a X ! i .6 ss ££ \ \ s \ .8 ^ s ^ -

1 L 10 100 1000 10000 [Tl TIME SINCE PUMPING STARTED (MINUTES)

PROJECT: LONG PRAIRIE WELL NO.: 14C AS= FILE: 0871026013 0- 222 USGPM T- LOCATION: MINN S.W.L.- 12-. 59 FT S« MALCOLM PIRNIE FIGURE 1 TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALYTICAL DATA NArtE LCN6 PRAIRIE RI/FS

VOLATILES

SAflPLE NIMBER 14C 14C 14C/FB 8AL 2B/FB BAL 2B/FB BAL 2B/FB BAL 2C BAL 2C BAL 2C/F?: ROUND 11 «2 43 tl 42 43 41 42 43 JlflTRII iAm HATER MTER HATER WTER HATER HATEJ? HATER HATER : UNITS U6/L U6/L U6/L UE/L U6/L U6/L U6/L U6/L J6/L ,

Chloroiethane NS NS i Broiotethane NS W NS 1 DichlarodifluoroMthane NS III NS ; Vinyl Chlonoe NS Ui NS 1 Chloroethane NS NS ; A«thylenc Chloride NS NS i TrichlorofluoroKtnane MS NS I 1,1-Dicnloroetnylene NS 0.5B 0.6B/ NS i 1,1-Dicnloroetliane NS NS ! Trans-1 ,2-Dicfiloroethylene NS /L NS i Cis-J,2-Dutiloro«hylene NS /0.6 NS Chlorofcn NS 2.4B/1.5B 11. OB N5 A TQ 1,2-Dichloroetnane NS • V. *a /0.9 /O.SB 0.9 NS 1.7; ! l.l.l-7r:chioroethane NS NS Car oon Tetricnlonoe NS NS • Broiodicnloroiethane NS NS ,' 1,2-Dichloropropane NS NS ; Cis-l,3-Dichloro-l-propent SS hS ; 1,1,2-Trichloroethylene NS 0.6B O.iB/ 0.6B/ NS [ Diorotochloroitthane N5 /l.O NS 1 1,1,2-Trichlorotthanc NS /F NS Transl ,3-Dichioro-l-propene NS O.o8 0.5B/ US ] 2-ChloroithYlvinylethtr NS If NS • Broicfort NS NS i 1,1,2,2-Tetractiloroithane NS 3/S NS 1 , 1 ,2,2-T«trachloroetnylene NS III 1.2/1.5 NS U/ , Chlorooenzene NS I 11 NS

Blink space - caioound analyzed for but not detected

*S - not saiplea

4-33 MRNI: 'CONTINUED NEXT PAGE! TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALYTICAL NAHE LONr rSAIr.IE RI/FS

VOLATILE3

SAMPLE NUNBE- CITY «»3 CITY M3 CITY HI5 CITY Ml CITY Ut4 CITY «M CITY «5 CITY HIS cr- «*5 ROUND 11 »2 13 11 12 13 tl •2 13 HATRII HATER WATER HATER IATER WATER HATER HATER ilATEn HATER UNITS U6/L U6/L US/L UB/L U6/L U6/L U6/L U6/L UB/L

Chlorofethane NS NS NS NS NS NS Broioiethane NS NS NS NS NS NS DicMorodilluoroietnine NS NS NS NS I. NS NS Vinyl Chlonae NS NS NS NS NS NS Chloroethane NS NS NS NS NS NS Nethylene Chloride NS NS 3. IB NS NS 4.1 NS NS Trichiorofluoroiethane 3.8B NS NS NS NS 1.6 NS NS 1,1-Dichloroethylene 0.4 NS MS NS NS NS NS 1,1-Dichloroethane NS NS NS NS NS NS Trans-1 ,2-Dichloroethylene NS NS NS NS NS NS Cis-l,2-Dichloroethylene NS NS 8.2C NS NS 4.5C N5 NS Chlorofori NS NS NS NS 1.5 NS NS 1,2-Dichloroethine l.BB NS NS NS NS 0.9 NS NS 1,1,1-Trichloroethane O.aB NS NS NS NS 1.0 NS NS Carton Tetracnionce NS NS NS NS NS NS Broiodichloroietnane X NS NS NS NS 0.4 NS NS 1.2-DichloroproDane NS NS NS NS 0.6 NS NS Cis-1.3-Dichloro-l-prooene NS NS NS NS NS NS 1,1,2-TrichloroethYlene NS NS 9. OB NS NS 4.0 NS NS Dibroiochloroietnane 2.16 NS NS NS NS NS NS 1.1,2-Tncnloroethane NS NS NS NS NS NS Tran«l,3-Dichloro-l-prop«ne NS NS NS NS NS NS 2-c/rl oroethyl vinyl etktr MS US NS MS K5 « Broiofon NS NS NS NS NS NS 1.1,2,2-Tetrachloroetnane NS NS NS NS NS NS 1.1.2,2-Teiracniereethyiene NS NS 220C NS NS 24C NS NS Chloroben:ens NS NS NS NS NS NS NOTES: Blank spice - csioouno inaly:ed rsr but not detected NS - not satolea

4-34 P1RNIE 'CONTINUED NEXT PAGE! TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALYTICAL DATA NAKE LDN6 PRAIRIE Rl/rs

VOLATILEs

SAMPLE NUMBER CITY H46 CITY H46 CITY H46 ITB Id/13/ TP 12/22 TP 2/9 TP 10/14 TP 12/23 TP 2/10 ROUND 11 12 13 ! tl 12 13 tl t2 13 HATRII MATER MATER HATER i HATER HATER HATER HATER •ATER HATER UNITS U6/L U6/L U6/L ! U6/L UB/L U6/L U6/L U6/L U6/L

Chloroitthane NS ! Broioiethane NS : Dichlorodifluorotethane NS i Vinyl Chloride NUfS> 1i Chloroetnine NS i I flethylefle Chloride NS i TnchlorotluoroMthane NS : 1,1-Dichloroethylene O.SB NS i 1,1-Oicliloroethane NS i Trans-l,2-Dichloroethylene NS : Cis-l,2-Dichloroethylene X NS ! O.b Chiorofon 1.1 NS ! 3.7B 1.4B 1.9E> 1.2-Di:Moroethane O.b 0.46 NS i 0.6B 0.9 D.6B 1.1.1-Tnchloroethane NS ! Caroon Tetrachionde NS I Eroiodichlorciethtne NS I 1.2-Dicnloroprooane NS ! Cis-l,3-Dicnloro-l-prooene NS ! 1,1.2-Tnchloreetnyiene 1.2 0.66 NS i 1.0 Dibroiocnloroiethane NS 1.1.2-Tnchloroethane NS : Transl ,3-Dicnloro-l-orooene 0.56 NS I 2-Chloroethylvinyletner NS ; Broiofort NS ; ;.i.2,2-Tetracnloroethane NS : i . i ,2.2-Tetracnloroetfiyiene NS : i Chiorofien:ene NS

NOTES: film soace - coioouno analyred tor but not Detected NS - not said leu

MAlflXM 4-35 PIRNIE ;CONTINUED NEXT PAGE) TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

ANALYTICAL DATA NAflE LONP PRAIRIE RI/FS

VOLATILE:

SAMPLE NUMBER TP 2/11 TP 2/11 DRY CLR W 13C FB ROUND 11 11 13 12 11 11 tl 11 tl MATRIX HATER MATER MATER MATER MATER MATER. MATER MATER MATER UNITS U6/L U6/L U6/L U6/L UE/L U6/1 U6/L U6/L U6/L

Chloroiethane 8ro«o§ethane Dichloroditluoroiethane IJ Vinyl Chloride XJ Chloroethane Nethyline Chloride TrichlorofluoroHthtne 1,1-Dichloroethylene l.l-Dichloroeth«ne Trans-l,2-Dichloroethylene Cis-l,2-Dichloroethylene Chlorofori 1.9B 1,2-Dichloroethane 0.4B 1.1,1-Tnchioroethan* Carbon TetracnJonoe JroiodicnloroMthane 1,2-Dichlorooropane C:$-l,3-Dichloro-l-proDene 1.1,2-Tricnloroethylene 2.0J Dibroiochloroiethane 1.1,2-Trichloroethane Transl .J-Dichloro-l-prooene 2-Chloroethylvinyiether BroicHon 1.1,2,2-Tetrachloroethane 3.7 1.1 ,2,2-Tetrachloroethylene 3.7J C.niorooenzene

NOTES: Blank soace - coipound analyzed for out not detected

NS - not saioled

4-36 MAU3XV1 PIRNIE (CONTINUED NEXT TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

i. DATA NAME

vOLATiLEs

SARPLE NUMBER 314 6th st. 214 1st ive. 410 1st tve HE ROUND il 11 13 MATRIX HATER MATER MATER UNITS U6/L U6/L UE/L

Chloroiethane BroiOMthane DichlorodifluoroMthant Vinyl Chloride Chloroethane Hethylene Chloride Trichlorofluoroiethane l,l-Dichloroetfivl«n* 1,1-Dichloroethane Trans-l,2-DichloroethYlent Cis-l,2-0ichloroethyltni L Chlorofori 0.5 1,2-Qichloroetnane 1,1,1-Trichloroethane Carbon Tetrachloride Broioaichloroiethane 1,2-DicnloroDrooant Cis-l,3-Dichloro-l-orooene I l.l,2-Trichloro«thylene Dioroiochloroiethine 1,1,2-Trichloroethane Transl ,3-Dichloro-I-propene 2-Chloroethylvinvlether Broiolon 1,1,2,2-Tetrichioroetnant 1,1,2,2-Tetrachloroethyiine 2.1C Chiorooenrent

NOTES: Blank space - coioound analyzed tor but not detected

NS - not sue led

VW£OLM 4-37 PIR>JIE ICONTINUED NEXT PAGE; TABLE 4-10 ANALYTICAL RESULTS-USEPA METHOD 601

If the result is a value greater than or equal to the detection limit, report the value. Compound was confirmed by secondary column as specified in Method 60IB. This flag is used when the analyte is found in the associated blank as well as in the sample. It indicates possible/probable blank contamination and warns the data user to take appropriate action. Dibromochloromethane, 1,1,2-Trichloroethane, and 2-Chloroethylvinyl ether co-elute. Compound level was too low to be confirmed and compound was calculated as Dibromochloromethane. Trans and cis-1,2-Dichloroethylene co-elute. Compound level was too low to be confirmed and compound was calculated as cis-1,2-Dichloro- ethylene. 1,1,2,2-Tetrachloroethane and 1,1,2,2-Tetrachloroethylene co-elute. Compound level was too low to be confirmed and compound was calculated as 1,1,2,2-Tetrachloroethylene. Dichlorodifluoromethane and Vinyl Chloride co-elute. Compound level was too low to be confirmed and compound was calculated as Dichloro- fluoromethane. There is a peak at the appropriate retention time for this contaminant which was distinguishable from noise but was less than our defined detection level. Estimated Value, Compound present at approximately the concentration reported.

FF Dibromochloromethane, 1,1,2-Trichloroethane, and 2-Chloroethylvinyl ether co-elute. Compound level was calculated as Dibromochlorome- thane, based upon confirmatory analyses performed during Round 1.

LL Trans and cis-1,2-Dichloroethylene co-elute. Compound level was calculated as cis-1,2-Dichloroethylene based upon confirmatory analyses performed during Round 1.

SS 1,1,2,2-Tetrachloroethane and 1,1,2,2-Tetrachloroethylene co-elute. Compound level was calculated as 1,1,2,2-Tetrachloroethylene based upon confirmatory analyses performed during Round 1.

RR Dichlorodifluoromethane and Vinyl Chloride co-elute. Compound level was calculated as Dichlorofluoromethane based upon confirmatory VWOXM analyses performed during Round 1. PIRNIE 4-38 LONG PRAIRIE, MINNESOTA

• IIItTIN* HOHITOII Will tOCAttOH*

yV*!»W-n^-B';jj-u 11 > -«- '/7j» • n IV ' '••n- ^^•Jv 'D •—J II h-r' . ^K^ —»^'« •

MALCOLM PMMW. INC. MAUDCDIAA NEW AND EXISTING MONITOR WELL LOCATIONS PIRNIE FIGURE 4- 9 ANALYTICAL DATA TABLE 4-11 LONG PRAIRIE RI/FS DATE: 03/13/87 CASE: PUW TEST

VOLATILES

SAMPLE NUMBER TRIP BLK tl 12 13 14 15 16 NATRIJ MTER HATER HATER HATER HATER HATER HATER UNITS uq/1 uq/1 ug/1 ug/1 ug/1 ug/1 ug/1

mmm ,, ChloroMthant 6roto«thant DichlorodHluoroMthane I Vinyl Chloride Chloroethani Hcthylint Chloridi TrichlorofluoroMthani 1,1-Dichloroethyltne 1,1-Dichloroithane Trans-l,2-Dichloroithylint LL LL LL LL LL LL Cis-1 ,2-Dicnloro»thyltnt 7.4 5.3 8.1 8.2 8.3 5.6 Chi or of on 1,2-Dichlorotthane 1,1,1-Trichloroethane Carbon Titrjchlonde BroiodichlDroatthant 1,2-Oichloropropine Ci s-1 , 3-D) chloro-1-propcni 1,1,2-Trichlorotthvlini 7.5 7.8 7.7 7.6 7.9 7.8 DibrotochlorD»thane 1,1,2-Trichloroethant Tr»nsl,3-Di:hloro-l-propin» 2-Chlorotthylvinyltthir Broio4ori 1,1,2,2-TftrachlorMthani SS SS SS SS SS SS 1 , 1 ,2,2-TetrachJor otthylMt 84 no 170 160 210 200 Chlorobenzeni

NOTES: Blank ipact - compound analyzed for but not dettcttd E - analvsii did not past BA/SC riquirmnts J - compound prtstnt btlo* tht sptcifitd detection Hut

(NOTES CONTINUED NEXT PAGE)

4-39 TABLE 4-11 If the result is a value greater than or equal to the detection limit, report the value. Compound was confirmed by secondary column as specified in Method 601B.

B This flag is used when the analyte is found in the associated blank as well as in the sample. It indicates possible/probable blank contamination and warns the data user to take appropriate action. Dibromochloromethane, 1,1,2-Trichloroethane, and 2-Chloroethylvinyl ether co-elute. Compound level was too low to be confirmed and compound was calculated as Dibromochloromethane. Trans and cis-1,2-Dichloroethylene co-elute. Compound level was too low to be confirmed and compound was calculated as cis-l,2-Dichloro- ethylene. 1,1,2,2-Tetrachloroethane and 1,1,2,2-Tetrachloroethylene co-elute. Compound level was too low to be confirmed and compound was calculated as 1,1,2,2-Tetrachloroethylene. Dichlorodifluoromethane and Vinyl Chloride co-elute. Compound level was too low to be confirmed and compound was calculated as Dichloro- fluoromethane. There is a peak at the appropriate retention time for this contaminant which was distinguishable from noise but was less than our defined detection level. Estimated Value, Compound present at approximately the concentration reported.

LL Trans and cis-1,2-Dichloroethylene co-elute. Compound level was calculated as cis-1,2-Dichloroethylene based upon confirmatory analyses performed during Round 1.

SS 1,1,2,2-Tetrachloroethane and 1,1,2,2-Tetrachloroethylene co-elute. Compound level was calculated as 1,1,2,2-Tetrachloroethylene based upon confirmatory analyses performed during Round 1.

RR Dichlorodifluoromethane and Vinyl Chloride co-elute. Compound level was calculated as Dichlorofluoromethane based upon confirmatory analyses performed during Round 1.

4-40 Analyical results of the sample from municipal well 3 did not indicate significant levels of contamination. While several analytes were detected such as methylene chloride, trichlorofluoromethane, chloroform, 1,2-dichloroethane, and 1,1,2-trichloroethylene, it is noted that all of these except trichlorofluoromethane were also found in laboratory blank analyses indicating possible or probable analytical method contamination. Trichlorofluoromethane is found at a low concentration of 0.4 ug/1. This contaminant was found at low concentrations in municipal well 5 (at 1.6 ug/1), monitoring wells 6A (at 2.5 ug/1) and 7A (at 0.7 ug/1). However, it was not detected again in monitoring well 6A during Round 2. The analytical results of the remedial investigation from municipal well 3 compare favorably to those obtained by MDH from August, 1983 through April, 1984 in which no contamination was found (see Table 4-4). Additional monitoring of groundwater in Long Prairie should include sampling of Municipal well 3. Sampling of that well can be discontinued following confirmation that the well is not contaminated. * Analyses of municipal well 4 which has not been used as a source for potable water since October, 1984, indicate contamination by three contaminants. These include cis-l,2-dichloroethylene, 1,1,2-trichloroethylene, and 1,1,2,2-tetrachloroethylene. In municipal well 4 as in all of the wells sampled during the remedial investigation, the contaminant found at the highest levels is PCE. This analyte was detected at 220 ug/1 in Round 1 and at concentrations increasing from 84 to 200 ug/1 through the hydrogeologic investigation. The other two analytes detected were present in concentrations less than 10 ug/1. Analytical results of the samples obtained during the hydrogeologic investigation are given in Table 4-11. It is noted that in comparing the RI analytical results to those obtained by MDH in 1983 and 1984 (see Table 4-4), the RI results are approximately doubled. These continue a general increasing trend noted in the MDH results.

REPT4/tdg 4-41 J

Drawdown and Recovery Data

2a 11107:5-1 '07:36:37 1 15.01 3 10.74 i 14.91 S .18.73 __ 4a Hi06sS4 07:56:34 1T..OI 3 '10.74 14.91 5 ' 18.73 15:27:54 . 14.74 3 19.40 Ili03t54 ' 07iS6:27 15.01 5 18.74 i 14.91 S IB. 73 15:26:54 14.73 S 10.4IJ Ilt04i34 p7:36:24 1:5.01 S 10.93 j 14.91 S 10.74 15:23:34 14.73 3 .19.411 lli03iS4 ?7iS6t 17 15.02 5 18.74 j 14.92 3 18.73 15:20:34 14.74 S -10.42' Ilt02i34 57:36: 14 • 15.02 3 IB. 94 i 14.71 3 18.73 I5i 17:54 . 14.74 S 18.421 1 It01s34 14.72 - 3-- 18.73 !>7i 36:09 15.01 5 18.94 j 13: 14:34 14.74 3 IB. 42, lliOO:S4 14.72 'S 18.74 »9 i 56 t04 15.02 3 10.94 i IS: 1 It 54 14.74 3 IB. 43; : 10:57:54 14.72 5 18.74 »9:3S:59 15.02 G IB. 95 l5iOB:34 14.74 S IB. 43. 10iSOi54 14.92 3 10.74 X>9:33:34 IK. 02 S 18.74 13:05:34 14.74 3 10.43! I0i57t34 14.92 5 10.74 »9:33t49 15.02 ;S IB. 94 13:02:34 14'. 74 S lB.43i , : 10:36:S4 14.73 3 18.73 p9t33t44 15.02 S IB. 94 14:57134 14.74 S 19.43J 10i35i54 14.73 S 10.76 p9 155:39 15.02 5 18.94 14:36:34 14.74 3 1B.44: 10iS4:34 14.73 3 .18.73 .17 1 S3: 34 15.02 3* IB. 74 14:33:54 14.74 3 18.441 10:33:54 • 14.73 3 1B.7S 14:50:54 •14.74 3- -18.44| )7:5S:27 15.02 S 18.95 I0i52i54« 14.73 5 ' 10.76 ;>7:33:24 15.02 S 10.93 14l47t54 14.79 3. 18.44! lO:31tS4 14.73 3 18.73 )9:S3: 17 15. O3 3 18.95 14:44:34 14.73 3 IB. 441 : 10i30i34 14.73 3' 18.76 14:41:34 07tS3tl4 l'J.03 S IB. 73 14.73 S IB. 43! IOi4?iS4 14.94 3 10.77 14:30(34 14.73 3 1B.43J 37tSSi07 15.03 5 18.95 10t40tS4 14.94 a ' 19.77 14:35:54 14.73 3 18.43J >9tS3t04 15.03 3 IU.73 ,10i4'/i34 j 14.94 3 19.77 14:32:34 14.73 3 19. 43! )7tS4tS7 15.03 3.- IB. 75 • 10:46:54 14.93 3 19.79 14:27s34 . 14.73 5 10.43, :>9:34:34 IS. 03 3 IB. 76 I0i43t34 ' 14.93 ' 3 . 19.77 14:26:34 ' 14.73 3 lB.46i >9:54:49 15.03 3 10.75 10:44:34 14.93 3 . 10.77 !4i23tS4 14.76 5 19.47* 07i34:44 IM.03 3 10.76 10:43tS4 14.95 3 10.79 14:20:34. 14.76 3 . 19.46' >9 154:39 15.03 3 10.76 10s42lS4 14.93- 3 18.79 14 i 17:34 14.76 3 19.46! J7t34t34 15.03 a 10.76 10i41t54 14.95 S 18.78 14: 14:34 14.76 9 18.46 :>7iS4:27 If,. 03 5 10.76 10:40iS4. 14.96 S ' 10.77 !)4: I 1:34 ' 14.77 3 JB.46' 09 i 34 t 24 113.03 JS 10.76 10i37:E4i 14. 76-' 3 18.77 14:00:34 14.77 3 19.47] 07t34i 17 15.04 Is 10.76 10:3BtS4 14.97 3 18.79 14:03:34 . 14.77 3 19.49' 07t34t 14 15.04 3 10.77 10:37tS4 14.97 3 ,, 18.79 14:02:34 14.77 3 . 19.47' 09 i 34 t 09 15.04 5 IB. 77 ,10:36:54 14.97 S . 10.79 13:57:54 14.77 3 19.47! •Jo9:S4:04 15.04 5 18.77 .10:35:34' 14.97 . S ' 10.79 13:36:34 14.77 3 19.47| p9:S3:39 IS. 05 5 18.77 ilO:34s54 14.77 '.3 -10.00 13:53:34 , 14.77 3 19.4Bi 09t33t34 15.03 3 18.77 ;iOi33t34 14.90 ' S ' IB. BO 3:30:34' « 14.77 S IB. 481 |09tS3»47 IS. 03 S IB. 77 ,10:32t34 14.98 3 18. OO' 13:47:54 '! 14.78 3 1B.48J ;09tS3:44 15.03 3 18.77 10.31:54 14.98 3 10.00 13:44:34 14.79 3 19.49. )9tS3t39 I'.i.OS. 5 1B.7B . 10:30:34 14.98 ; 3 '"10.00 13:41:34 14.70 3 '10.48 ;09t33i34 13.03' 5 IB. 713 ; 10:27:34 14.77 5 ; 10.01 13:39:34 14.79 3 18.49 07 : 53 t 27 15.06 5 10.97 ; : 10:20:34 14.77 . 3'. 18.81 13:35:54 14.77 3 1B.30J 09:33:24 15.06 5 10.77 i 10:27:54 14.77 3 '. 1B.B1 13:32:34 14.7? 3 19.31; 09:53: 19 15.07 S -17.0O 10:26:34 13.00 3 'lO.B2 13:27:34 14.79 3 19.30- . •09:33tl4 15.07 3 17.01 10:23:34 13.00 '5 ; IB. 83 13:26:34 14.90 3 18.31. »9tS3t09 15.07 5 17.01 10:24:54 13.00.. 3 •" 10.03 13:23:34 14.90 3 18.32 p9i33:04 15.00 5 17.03 10:23:54 15.01 , S ' 19.93 13:20:54 14.90 3 18.33, 07:32i57 It!. 07 3 17.04 10:22:34 13.01 ' 3 • 19.03 13: 18:54 14.80 3 19.32' p7t32:34 15.09 3 19.06 ' 10i21:34 15.01 3 19.03 13: 16:34 14.90 3 18.33. O7:32: 49 15.10 3 19.08 10s20:34 13.02 3 10.04 13: 14:54 14. BO 5 . 18.33 p9:32:44 15. 1 1 5 19. 1 1 r !Oi20t24 15. O2 3 10.94 13: 12:34 14.80 S . 18.341 07:52:37 15. 13 5 19. IS • lOi 17:34 • 13.02 3 10.93 13: 10:54 14. BO '3 ' 18.33 07:32:34 15. 14 3 ,.19.20 lOt 17:24 15.02 S 10.04 13:08:34 14.81 3 . 19.33 09:32:29 15. 15 5 19.26 i 10s 10:34 13.03' S 10.83 13:06:54 14.01 3 . 19.34 p9:52s24 15. 17 3 19.33 i lOi 18t24 15.03 S IB. OS 13:04:54 14.81 'S 18.33 O7:32: 19 15.19 5 19.43 . 10: 17:34 13.03 S 10.03 13:02:34 14.01 3 ' 10.33 Cl9t32t 14 15.21 3 ' 19.36 . 10: 17:24 IS. 03 . 3 IB. OS 13:00:34 14.81 S 10.34 59tS2:09 15.23 5 19.72 * lOi 16:34 13.03 ' S . 10. OS 12:50:34 14.81 3 10.34 13.23 a 17". 73 ; >7iS2t04 lOi 16:24 13.03 3 10.E15 12:36:34 14.91 3 • 18.33 15.27 5 20.21 j :i7tSli57 lOi 13:54 13.04 . 3 IB. 115 12:54:54 14.81 • 3 •• 18.36 •;7:51:34 15.32 S 20. S/» ! 10:13:24 13.04 S 18.06 12:52:34 14.91 S ' IB. 36 . 15.37 3 20.63 07s 51 1 53 lOi 14:34 13. 04 3. 1B.CJ6 12:30:54 14.81 S . 18.57 ! : (07:31:32 13.33 3 2O.73 j lOt 14124 13.04 3 10. B6 12:48:34 14.81 3.' 18.37*1 15.34 3 2O.-03 ' »9l31l31 lOt 13l34 13.03 3 -10.07 12:46:34 14.82 S 18. SB 07:31:50 15.33 a 20.73 10:13:24 15.03 • 3 18.06 12i44tS4 14.82 3 . 18. SBJ i07:31l49 15.33 3 21. O3 i lOi 12:34 15.03 . 3 10.87 12:42:54 14.82 3' IB. SB ;09:31:4B 15.36 3 21.14 10: 12:24 15.03. 3 . 10.07 12:40:54 14.82 3 IB. SB: \O9iSli47 15.37 3 21.25 10: 11:34- IS.O6 3 ...10.88 12:30:54 14.92 3 19.39! ' )09iSli46 15.30 3 21.30 10: 11:24 15.06 3 10.80 12:36:34 14.92 3 18.37 .09: Sit 45 15.37 S 21.52 10: 10:34 IS. 06 S 18. 8B 12:34:54 14.02 3 1B.37J 115.37 ' a 21.66 •09:31:44 lOt 10i24 15.07 5 10.87 12i32:34 • 14.02 3 18.38' yj7i31 1 43 15.40 5 21.00 10:07t34 14; 93 • S 10.07 12:30:34 14.83 5 18.39 13.41 3 21.73 io7tSl:42 10t07i24 14.75 5- 10.07 12:20:34 14.83 5 18.60 |07:51:41 15.42 3 22.12' 10lOBtS4 • 14.73 3 • 18.00 12:26:54 14.03 3 ' 18.39 13. -12 3 22.20 tO7:31:40 10:00:24 14.76 ,5 18. BB 12:24:34 14. 83 5 1B.60J •07i Sit 37 15.43 5 22.46 10t07tS4 14.76 •' S '. 18.88 12:22:34 14.83 S 18.61 :09:31:3H 15.44 a 22.64 10:07:24 . 14.76 5'.' 18.88 12:20:54 14.83 3 18.62 •07i 31 1 37 TJ.45 5 22.9'J 10:06:34 14.76'. S ; 18.88 12: 10:34 14.83 3 18.61 109:31:36 15.46 5 23.03 10:06:37 14.76 3 ' 18.88 12: 16:34 14.03 3 . IB. 62 15.47 5 23.27 ',09:31:35 10:06:24 . 14.76.; 3 • 10.07 12: 14iS4 14.83 S 18.62 ',09:31 :34 13.47 3 23. SO 10:06i07 14.76 ' 3 . 1O.07 12: 12:34 14.83 S 10.62 .07: 51 133 15.40 S 23.73 10:OSi34 14.76 3 18.00 12: 10:34 14.84 3 18.62) '07 1 31 : 32 15.47 3 24. OO ' 10:03:39 14.77... S ;.i 18.07 12:00:34 14.84 3 .19.63 p9iSlt31 15.50 5 24.20 10:03124 14.77 " S" IB. 07 12:06:54 14.94 3 18.63! |09i31t30 15.51 3 24.56 10:05:09 14.77 3 10.07 12:04:34 14.84 3 18.64 p9:Sli27 15.51 5 24. O6 10t04:34 14.77 3 18.87 12:02:34 14.03 3 18.64 I5.5'.i a 23.10 •07: 31: 20 10:04:39 14.77 3 10. 7O 12:00:34 14.83 S 1B.64J 15.53 0 23.51 Io7t31:27 10:04:24 14.77 S 10.87 11 ISO: 34 ' 14.83 3 18.64 15.5-1 3 23.07 ;0?iSl:26 10:04:09 . 14.77 5 10.07 11:56:34 14.83 S 18.63. 15.515 S 26. 24-- 07t Sit 23 10:03:34 14..77 3 10.70 11:54:34 14.83 S 18.63; 15.53 3 26.64 iO9:31:24 10:03t37 14.97 ' 3 18.70 11:52:34 14.89 3 18.66- |09s51t23 15.56 S 27. OS 10:03:24 • 14.78 3 18.87 11:50:54 14.89 3 IB.66: 15.57 55 27.47 07:31:22 10:03:07 14.70 5 10. 7O 11:48:34 14. 83 , 3 ' 18.66 15.57 S 27.76 ' 09s Sis 21 10t02:34 14.90 3 19.70 11:46:34 14.86 3-' 18.66' ,09s 31 120 15.50 3 2B.46 : 10:02:37 14.78 S 18.70 11:44:34 14.86 3. 18.67 15.57 3 2B.77 : jO9i51i 17 10:02i24 14.90 3 1B.7O 11:42(54 14.BV -a- IB. 67. 143.37 '3 27.73 .' •O7»31r 1O 1O:02:O7 14.90 5 10/70 1 1 MO:U4 14. Bi • S --1B.67. IG.S7 3 30.27 \O7t3li 17 10:01:34 14.90 3 IB. 70 11:38:34 14.07- S't IB. 68 (09:31: 16 15. &O S 31.12 10:01:37 14.97 'S 1B.9O 1 1 3&| $4 14. B7 S IB. 69 15.61 5 32.03 »9l31tlS 10:01:24 14.79 5 18.90 1 : 34 : S4 14.87. 3 ..18.69* :09tSl:14 13.61 3 33.03 10:01l09 14.99 3 10.71 'O9i51l 13 15. 6O S 31.31 10:00:34 14.77 a 10.91 11130134^" ~'l4^B8~^a~iBr70 . J07 s 3 1 1 1 2 ' 15.61 S 33.70 ! 10:00:39 14.79 3 10.71 {ill 2131 94. •14.88 3 t- 18.671 •09i 31l 11 15.61 5 33.90 10tOOl24 14.77 3 IB. 91 Ili26t34- 14.88 .8 : 18.71 :09tSlt 10 15.61 3 33.70 . 10:00:07 14.77 3 10.71 11:2-1:34 .'14.88.. 3. 18.70 \37i3ll07 15.6J 3 33. 7B : 09i39tS4 14.77 3 10.92 11:22:34 14.89 3 ,-18.71 1 •07:31:08 13.61 3 33.70 O7:S7t37 14.77 3 10.72 14.89 si 9 i: 18.721 J09:31t07 15.61 S 33.70 11:20:34 i>9i59i24 13.00 3 18.72 14.89. '3 18.72' ,09: 31 1 06 15.61 S 33.70 11:17:54; "09iS9i09 13.00 3 10.72 Hi 111:34 14.89 3 18.721 'O9s51sOS 15.61 3 33.78 j •09:50:34 IS. 00 S 10.72 1 III'/: 54 14.89- 3 10.72' Jo9i31t04 . 15.61 3 33.90 •159 1 SOt 37 13.00 3 18.72 11:16:34. • 14.89 • S 18.72 07: 31 103 15.61 5 33. 7U ! j 07tS9:24 13.00 3 10.73 . 14.89 3 18.73. 07:31102 • PJ.61 3 33.98 . 11:15:34 !'07i50t07 15.00 3 18.73 lit l-ltS4 14.90. 3 18.72; p7l31iOl 15.61 S 33.98 J07l37t34 15.00 3 19.73 lit 13:34 • ,14.90 3 18.72 l07s31iOO 15.61 S 33.70 07l 37 1 37 15.00 3 19.73 .14.90 3 '18.72' »7«SOl57 15.61 3 33.90 lit 12:34 p9l37l24 13.01 3 10.73 .•14.90 3 18.72 »7 ISO ISO 15.61 S 33.70 11: 11:54 O9l37i09 IS. 01 5 19.74 Ilsl0t34 •-"14. 90 3 18.73' 07»50i57 15.61 5 33.78 p9i96iS4 13.01 . 3 18.94 V14.91 S . 18.73; 07 i 30 i 56 15.61 S 33.70 ; 111 07 1 34 07 t 56 i 47 IS. 01 3 19.73 11:00:34 *; 1 14.91 3 : 18.73' »7l30lS5 15.60 3 33.77 , J07lS6i44 13.01_3 . 19.74 •07 1 SO 1 54 15.37 S 33.67 - - 3b ' • "' 1 1 2b

Channel 1 for Municipal Well 5 Channel 5 tor Municipal Well 4- rn fz:i

DravvoWvn and Recovsry Data cont. 5a 23i35 HRS B7/O3/14 1106 7a 1 14.07 5 17.17 D • 0. (10:05:27 16.30 5 32.33) 23«03 HRS 1 4 . 07 5 ! 17.47 .6a 10:00:37 16.38 : 5 32. 17. !lO:03:24 16.38 S 32.34J 22:33 HRS 14.07 j 3 17.46 1 10:00:53 1 16.38' S 32. 16j .; !lO:013:2l 16.38 3 32.33 22:05 HRS 1 4 . 1 0 '3' 17.36 10:00:54 16.3B •' 3 !lO:03: 18 16.38 S 32.53 2li33 HRS 1-1.09 .' 3 ' 17. SO 1 32.10: ; 10:00:53 1 16.38. 3 32.07, •, I |lO:03: 13 16.38 3 . 32.33 SI: OS IIRS 11.10 3 17.51 ;iO:O13: 12 . 16.38 3 32.33 20:33 HRS 14.10 3 . 17.31 10:00:31 I 16.30 ,',S •"32.04, ' 10:00:30 'I 16.3B'.-;5 ;: 31.93 ' ,10:03:07 16.38 3 32.34* .20:03 HRS 14.11 3 17.33 10:05:06 1 10:00:48 16.38 S 32.54 I?i33 HRS 14.11- 3 17.33 I 16.38 '. S.'31.70 / 10:00:47 16.30 31 .02 10:03:O3 16.38 3 32.34! 19:03 HRS 11.11 5 17.54 1 O:03:00 16.38 3 32.34' I0t33 HRS 1 -1 . I I 3 17.33 10:00:46 1 16.30 "31 80 10:00:44 16.38 68 10:04:37 16.38 3* 32.34. 18*03 HRS 14.12 3 17.53 1 31 10:00:43 16.38 62 10:04:54 16.38 5 32.34 t7«33 HRS 14.13 3 17.56 1 31 10:00:42 1 16.30 31 ss! 1 0:04:31 16.38 S 32.34 17:03 HRS 14.13. 5 17.56 1O:O4:40 16.38 5 32.34 llfei 33 HRS 14. 13 3 17.50 10:00:40 1 16.38 31 42 10:00:37 1 0:04:43 16.38 3 32.34 (16:03 HRU 14.11 U . 17.30 1 16.30 '31 33 10:00:38 1 16.30 1 0:04: 42 16.38 5 32.34 I3i33 HRS 14. 14 3 . 17.159 .31.22 '10:00:36 1 16.38 31.11 1 0:04:39 16.38 3 32.34' 13:05 HRS 14.13 S 17.60 10iOO:33 1 16.38 30. 99 1 O:04t36 16.38 3 32.54 14:33 HRS 14.13 3 17.60 10:00:34 1 16.38 '5 30.87 1 O:04:33 16.38 3 32.34 Mi OS HRS 14.16 5 17.61 10:00:00 1 16.30 -3 130.75 1O:O4t30 16.38 3 32.34 I3i33 HR3 14.16 3 17.62 10:00:31 1 16.38 .:.S '3O.61 1 0:O4i'.»7 16.30 3 32.34 I3t03 HRS 11.16 S 17.62 10:00:27 1 16.38 .' 5•30.46 !IO:O4:24 16.38 3 32.34 12:33 HRO 14.17 3 17.63 1O:OO:28 1 16.38-3 30.29 !!O:O4i21 16.30 3 32.34 12i03 HRS 13.31 S 17.63 10:00:27. _l T6.38 ' 3i3O.14 'IOiO4: 10,' 16.38 3 32.34 11.33 HRS 14.17 3 17.64 ;iO:04: 13« 16.30 3 32.34 IO:OO:23 16.38 29.90 J 1 1 t 03 HRS 14.17 S 17.66 r 'iOiO tri'i 16.38 3 . 32.34 !Oi33 HRB 14.113 3 1 7 . 67 10:00:24 i' 16.311 29.00 O:04:O9 16.38 3 32.34 KM 03 HRS 14.10 *J 17.67 10:00:23 i • 16.38 29.62 10:04:06 16.38 3 32.34 10:00:21 i 16.38 29.42 09:33 HRH 14.10 5 17.68 ! JIO:04:03 ' 16.38 3 32.34 10:00:20 i 16.38 29.23 09 1 03 HRS 14.10 3 17.67 | O:04:OO 16.38 3 32.54 ,'10:00: 17 i 16.38 08:33 HRS 14.17. 3 17.67 '29.03 0:03:37 • 16.38' . 3 32.34 10:00:17 i -16.30 28.77 lOBiOS HRS 14.17 3 17.65 i O:O3:54 16.38 S 32.53 lOiOOl16 .' 16.30 3 J07i33 HRS 14.21 3 17.72 i 28.30 O:03:3t 16.38 3' 32.33 07i 03 HRS 14.21 3 17.74 10:00:13 r 16.38 3 20. 14 0:O3: 48 16. 38 3 32.53' •06 1 33 HRS 16.30 3 17.76 lOiOOl13 i 16.30 3 •'27.7O 0:03:43 16.38 3 • 32.33 'Oil OS HRS 16.31 • S 17.78 10:00:12 i . 16.38 3 27. IB O:O3i42 16.38 3 32.33 •'03133 HRS 16.21 S 17.70 10:00:11 i 16.30 3 .'26.39 0:03i39 16.38 3 32.33 !03t03 HRS 16.09 3 17.79 10:00:07 i 16.30 3 • 23.91 O:03:36 .16.38 3 32.34 10:00:00 16.30 3 '04l 33 HRS 13.93 5 17.01 i 23.13 0:O3t33 16.38 3. 32.33 10:00:07 16.30 3 /Oil 03 HRS 15.51 S 17.06 i .24.25 Oi03:30 16.38-- 3 32.33 10:00:03 i 16.38 3 , 23.28 '.20:20 HRS 07/03/13 «O6 0:03:27 •16.30 3 32.33 10:00:04 t 16.30 3 22.20 • - • •• • 0:03:24 16.38- 5 32.33; •!lO:OO:03 i 16.30 3 20.99 [STATION ID • on O: 0.1:21 16.38 3 32.33: hlOiOOtOl i 16.38 5 19.65 120:16:54 1 14.69 5 •- IB. 19 Oi03: 10 •16.38 S 32.33 ,|l 0:00:00 i 16.30' 3 18.36 J20: 12:54 14.69 3 • 10. 19 10:O3t 13 " 16.30 3 32.33 :20:OB:34 14.69 5 •09:37:38 i 16.38 '5 . 17.6Si : IB. 10 17.27; 10:03: 13 16.38 3 32.33 •20 1 04 1 54 14.69 ;5 10. 19 09:59:57 i 16.38 '3 09:59:56 16.38 3 17.28 10:03: 11 16.38 3 32.33' 20«OOiS4 14.69 jS IB. 19 i1 17.35: 10:03:09 16.38 5 32.331 19t36i34 . 14.69 |3 10.20 09:59:54 i 16.38 3 07:33 HR3 B7/O3/16:«06 10:03t07 16.38 3 32.33' 19:32:54 14.69 5 10. 19 10:03:03 16.38 3 32.S3J 19:48:34 14.69 3 ' 18. 19 1 13.90 3 17.14' D 0. . 13.89 S 17 10:03:03 16.38 3 32.33i 19:44:54 14.69 5 18.19 09:03 HR3 1 14', 13.89 5 17 14 10:03:01 16.38 3 32.33 19i40i34 14.69 S 18.20 08:33 HRQ 08:05 HRS 13.90 5 17 13 10:02tS9 16.30 vS 32.33 19:36:54 14.69 S . 18.21 10:02:57 16.38 3 32.33 19:32:34' 14.69 3 i7:33 HRS 13.91 3 17. 18 .18.22 17.17 10:02:53 16.33 3 32.33 19:28:34 14.69 5 ' 18.22 !07:03 HRS 13.92 5 17. 19 10:02:53 16. 38 3 32.33 19:24:34 14.69J 3 10.21 !06:35'HRS 13.91 3 13.92 17.21 10:02:31 16.38 3 32.33 19:20:34 14.69 a 10.22 '06:03 HRS 5 ' * I 7. 2O 10:02: 49 16:38 3 32.33 l3i03 .HR9 13.92 3 13.93 S 17. 2O 1O:O2: 45. 16.38 S 32.33 19iOBl54 14. 7O 3 10.22 •1:33 Hr»3 !OlO2i43 16.38 3 32.33 04: OS.HRS 13.93 S 17.21. 17:04»34 11.70 3 IB. 24 10:02:41 16.38 S 32.33: 17lOOlS4 14.63 3 18.23 3:33 HRS 13.93 • 3 17.21 "03:03 HRH 13.93 S 17.21 10:02:39 16.38 3 32.33 18:56:34 14.70 3 . IB. 24 10:02:37 16.38 3 32.33 IBtS2tS4 14.70 S 18.24 .102:33 HRS 1 13.93 3 17.21 I02:03 HRS 13.94 3 17.22 10:02:33 16.38 3 32.33 1B:48:54 14.70 3 • 18.24 10:02:33 16.38 3 32.34 lSi44t34 14.70 3 • ' 10.24 ' »1:33 HRS 1 13.74 3 17.22 1)1:03 HRS 1 13.94 ' 5 17.23 10:02:31 16.38 3 32.34 IBtlOlSI 14.70 5 . 10.23 10:O2i29 16.30 3 32.33 lQi36i34 0.36 3 18.26.' X>0:33 HRS 1 13.74 • 3 17.23 >?0:03 HRQ 1 13.95 • 3 17.24 10:02:27 16.30 3 32.33 18i32i54 14.70 3 .10.26' 10:02:23 16. 38 3 32.33 I8t28i34 123:35 MRS 87/03/13 «06 14.70 3 18.26 10:02:23 16.38 3 32.33 !Bi24tS4 14.70 3 10.27 1 13195 3 17.24 D j.O. {23:03 HRS 1 13.93 17.24 10:02:21 16.38 3 32.33 t8i20i34 14.70 3 . in. 27 10:02: 19 16. 3B 3 32.34 18:16:54 14. 7O 3 18.28 22t33 HRS I 13.73 17.24 I 22:03 HRS 1 13.73 , 17.27 j 10:02: 17 16.38 3 32.34 IBi 12(34 14.70 3 18.27 IO:02: IS 16.38 3 32.33i 1BtOBi54 14.70 . 3 , 10.28 21:33 HRS 1 13.73 17.26| 21:03 HRS 1 13.76 17.26j 10:02: 13 ,' 16.38 . 3 32.34 18t04:34 14.70 3 ID. 27 16.38 3 32.34 20:33 HRB 1 13.76 17.261 10:02: 11 I8t00i34 14.71 S 18.20 10:02:09 20:05 HRS 1 13.76 17.20 I 16.38 3 32.34 17:36:34 14.71 3 1C. 23 16.38 3 32.34: 19:33 HR8 1 13.77 • 17.28 10:02:07 I7i32i54 14.6O S 1Q.20 16.38 3 32.34; 17:03 HRS 1 13.77 • 17.29 10:02:03 17i4BiOO 14.68 3 18.28 16.38 3 32.34) 18:35 HRS 1 13.77 3 ''.. 17.30 '• ilO:O2:03 17:44:34 14.63 3 18.29 • -16.38— 3--32iS3 18:03 HRS 1 13.77 • 3 -17.30 !lO:02:01- 17:40:34 14.64 3 18.29 16. 3B 3 32.33 17:35 HRS 1 13.77 S . 17.30 110:01:37 17i36i34 14.39 3 '. 18.29 16.38 3 32.36 17:03 HRS 1 13.?B 3 • 17.30 10:01:57 17t32i34 14.71 5 18.30 16.38 S 32.36 16:33 HRS 13.78' 3 17.30- 10:01:33 . 17:20:54 14.71 , 3 ' 18.30 16.38 3 32.56 16:03 HRS 13.7? S \17.32; 10:01:33 17t24iS4 . 14.71 3 10.30 10:01:31 16.38 • S 32.36 15:33 HRS 13.77- '3 r17.31• 17l20t34 14.71 3 • '18.30 10:01:49 16.38 3. 32.36 17i 16:34 : 13:03 HRH 13.77 .' 3' ;17.33 14.71 3 ' 10.31 ; 16.38 3 32.331 14:33 HRS is.??;. 3'- !'l7.32 10:01:47 17i 12:34 • 14.71 S 10.30 10:01:43 16.38 ' 3.- 32.37; 17:08:34 14.71 3 14:03 HRS 14.00'' 3 ';17.33 ' 18.31 : 10:01:43 16.30 3 .32.37J I7i04tS4 14.71 ' 3 •18.31 13:33 HRS 14.00 3• 17.34M 13l03 HRS 10:01:41 16.38 ' S 32.54 17:00:34 14.71 S .18.32 14.OO;^3: 17.34]' 12:33 HRS 1 14.0O. 3:.17.341 !OiOli37 111.38 • 3 32.37 16.36:34 14.71 .3 18.32 I3:O3'HR9 l^M.OlliS^iT.SSl! IOt01i37 lb.3a '9 .32.30 l6tS2lS4 14.71 '3 IB. 31 I6.3B". 3 32. V^ ll:35"»IRS~l 14.01 .51. 17.361 10iOI733 \bt AOtiA 14.71 3 IB. 33 IO:Ol i33 16.38 ' 3 32. SO 161 44134 14.72 S . IB. 33 1 1 I 03 HR3 1 ' 1 4 . O 1 !! 3 • 1 7 . 36 j' 10:01:31 16. 3O 5 32.37 ; 10:33 HRS-1-- 14.01-- 5-''- 17.36 [ 16:40:54 14.72 5 18.33 10:01:29 16.38 3 32. 53 16:36:34 14.72 13 18.34 10:03 IIR3.1 14.02'-."3 17.37 5.-17.37 10:01:27 16.38 3 32.56 16i32tS4 14.72 3 18.34 57:33 HRS 1 '.14.02 10:01:23 16.3B-'3 '32.34 14.02 3 '• 17.30 16:28:34 . 14.72 3 .'18.33 07:03 HR9 1 16.38 ..3 :32.S3 5 ! 17.37 10:01:23 16:24:34 14.72 3 ...IB. 33 00:33 HRS 1 14.02 .\3 17.40 10:01:21 16.39 '9 32.32 (6l20lS4 14.72 3 : la. 3-1 OB:03 MRS 1 14.02 IQtOl: 17 16.30. 3 32.31 16:17:34 07:33 HRS 1 14.03 ' 3 17.40 14.72 3 .' IB. 36 1 10:01:17 16.38 3. 32i31 14.03-' 3 IT .41 16:14:34 14.72 3 ..18.36 07:03 MRS 1 10:01:16 16.38 S 32.4?' 1 14.03'..5 17.41 : lit 1H34 14.72 3 18.33 06:33 HRS lOiOti 14 16. 38 S '32. SO* 14.03 17.42 16:08:34 1-1.73 3 VlB. 37 06:03 HRS 1 .•i. 10:01:13 16.30 3 32.47= : 14.04 17.43 16:03:34 14.73 3 • 18.37 03:33 HRS 1 10:01:12 16.38 3. 32.48. 14.04 ,.3 17.43 16:02:34. 14.73 3 ..10.37 03:03 HRS 1 1O:01: 10 16.38 .' 3;': 32.43- 14.03 .5 17.43 I3i37i34 r 14.73 :-3 -18.36 04:33'HRS 1 10:01:0? 16.38. 3 . '32.431 14.05 : 3 17.44 13:36:34 14.73 3 ,'•18.37 104:03 HRS 1 ' I0i01:07 16. 38 -3 30.72; 14.03. 5 17.44 13133134 14.73 -3 .-10.38 3:33 HHQ 1 10:01:06 16.38 3 32.3? 14.06 . S 17.43 13:30:34 14.73 • 3 .-. 18.38. ;03i03 HRS 1 ' 16.38 3 • 32.38 17.43 10:01:05 13:47:54 14.73 -3>V IB. 37 2:35 HRS 1 14.06 i'3 • , 16.38 :3 32.33 17.46 10:01:03 13i44:34 1 4 : 73 •' ' 3!''18.37 02:05 HRS 1 14.06'' 3 16.38 3 32.32 : 17.46 10:01:02 13:41:34 14.73 3 .'••18.39 '.Oil 33 HR3 1 14.07 .3 . 17.47 10:01:01 16.30 3 32.27! I3«38i34 '14.73 ' 3 '.18.40 '01:03 HltS 1 14.07' -'3 _. . .. 14.07 :'5 17.47 10:00:3? 1 16.38 ' 3 32.24] 15l33t34 . 14.73.: 5 •.'18.39' !00:33 HRS 1 10:00:58 1 16.38: '3 • 32.-2O; 14.07 3 17.47 13i32tS4 14.73 3 . 1B.4O • !00:03 HRS 1 6b 4b 5b '

Channel 1 lor Municipal Well 6 Channel 5 lor Municipal Well 4 Drawdown and Recovery Data cont. i\ 8a •i: 10:21:43 1 16.38 5 32.64 10:21:30 16.30 '3 32.64 10:21: IS 16.30 5 32.64 ;! 9a JIO:21:00 16.30 S 32.64 1 11:27:13 16.38 5 32." 76 1 10:20:45 16.3(3 3 32.63 11:26:13 16.38 5 32.77 10:20:30 16.30 3 32.63 11:23:13 16.38 5 32.76 10:20: 13 16.30 3 32.63 , 11:24:15 16.38 5 32.76 10i20iOO 16.38 5 32.63 11:23:15 16.38 5 32.76 10: 17:43 16.30 S 32.63 1 i 11:22:15 16.30 5 32.76 10: 17:30 16.30 5 32.63 . 11:21:13 16.38 5 32.76 10: 17: 13 16.38 3 32.63 • 11:20:13 1 16.38 S 32.76 1; 10: 17:00 16.38 5 32.63 11:17:13 1 16.38 S 32.76 lOi 18:43 16.38 3 32.63 11:18:13 1 16.30 5 32.76 10: 18:30 16.38 5 32.64 11: 17:13 16. 3O 3 32.76! 1O: 10: IS 16.38 3 ' 32.62 111 16: IS 16.30 5 32.76 10: 18:00 16.38 3 32.62 11: 15:13 16.38 5 32.76 10: 17:43 16.30 5 32.62 : i -1.0... _ t ll: 14:15 16.38' 5 -32.75, I3i32t 15 10: 17:30 16.38 3 32.62 s 16.38 S 32.83 .( ! 11: 13: IS 16.38 3 32.75 |10:17:1S 16.38 5 32.62 I3s30i 15 16.38 5 32.84 ; I1 li 12: IS 16.30 3 32.73] 13i2Gi 15 16.38 S 32.84 1O: 17tOO 16.30 3 32.62 '. 1O: 16:43 16.38 3 32.62 lit 1 1: 15 16.38 3 32.75' 13i26i 15 16.38 3 32.64 11:10:13 16.30 3 32. 7Sl 13»2-lt 13 l|6.38 S 32.84' 10: 16:3O 16.30 5 32.62 11:07: 13 16.38 S 32.75? 10: 16: 13 16.38 . 5 32.62 13»22i 15 16.38 3 32.84 ', 11:00: 15 16.30 3 .32.73 I3t20i 15 16.38 S 32.84 lOi 16:00 16.38 5 32.61 i 1 1 :07: 15 16.38 3 32.73' 10: 15:43 16.30 . 5 32.61 13i 18: 15 16.38 3 32.83 ' 11:06:15 , 16.38 3 32.74 13> 16: 15 16.38 3 32.83 1O: 15:30 16.30 5 32.61 j 11:03: IS 16.38 3 32.74 10: IS: IS 16.38 5 32.61 13i lit 15 16.38 3 32.83 • t ' 11:04: 15* 16.38 5 32.74 13i 12:15, 16.38 3 32.83 10: 15:00 16.30 S 32.61 ', lOi 14:43 16.30 3 32.61 IH03: IS 16.38 3 32.74 13: 10: 15 16.30 S 32.83 l!' 1 1:02: 13 16.38 5 32.74 13tO8t 15 1 6 . 38 3 32.83 lOi 14:30 16.30 5 32.61 • J! 10:14:13 • 16.30 5 32.61 11:01: 13 16.38 3 32.74 13i06i IS 16.30 5 32.83 1 16.30 5 32. 6O '•\' 11:00; IS 16.38 5 32.73 13t04i 15 16.38 S 32.82 10: 14:00 ' i' 10: 57: 15 16.30 5 32.73 10: 13:45 1 16.30 5 32.60 j 13i02i 15 16.38 S 32.82 M; 10:58: 13 16.38 5 32.73 13:00t 15 16.3O S lOi 13:30 16.38 5 32.60 ; : 32.82 • j 10:37: 13 16.38 3 32.73 10: 13: 13 16.30 ' 3 32.60 12:50:15 16.30 3 32.82 i 10:56:13 16.38 5 32.73, 12:56: 15 16.38 10: 13:00 16.30 5 32.60 :i S 32.82 10: 12:45 16.30 5 32.60 10:35:45 16.30 5 32.73 12i54i 13 16.38 S 32.82 •i lOiSS: 15 16.38 ' 3 32.72 lOt 12:30 16.30 5 32.60 ; 12:52i 15 16.38 S 32.02 10:54:43 16.38 3 .32.72, 12i5Oi 15 1 6 . 38 S 32.81 lOi 12: 13 16.30 • 5 32.60 i 10:34: IS 16.30 .5 32.72 10: 12:OO 16.30 5 32.5? 12:1(3i 15 16.30 3 32.81 % 10:53l 43 16. 3d 5 32.72 12:46: 15 16.38 S 32.81 10:11:43 16.30 3 32.57 10:53: 13 16.30 ' 3 32.72, I0illi30 1 16.30 5 32.57 •l! 12i 44: 13 16.38 S 32.81 • 16.30 S 32.57 j 10:52:45 16.'3B 5 32.72- 12i42: 13 16.30 3 32.80 lOi 111 IS • » ; 10:52: 13 16.30 S : 32.72 10: 1 li 10 16.30 5 32.57 ; 12:40: 13 . 16. 3O S 32.80 •!• 10:51:43 16.38 S 32.72. 16.38 5 32.57 ! 12:38: 15 ; 16.30 S 32.80 10: 11 105 ;' 10:31:13 16.38 S 32.72, lOt lliOO 16.30 5 32.57 i 12:36: 15 16.30 S 32.81 | 10:30:43 16.38. 5 32.71: 12:34: 13 16.30 S 32.80 10:10:55 16.30 5 32.57! i1 10:30i IS 16.30 S 32.71 I lOi 10:50 16.38 5 32.57 12:32: 15 16.30 3 32.00 i 10:47:45 • 16.38 S— 32.71 i 12:30: 15 16.38 3 32.77 lOi 10:43 . 16.38 5 32.37- 10:47: IS 16.38. S '32.71 10: 10:40 16.38 5 32.57 • i 12:20: IS 16.3Q 3 32.80 ! . * 1 0:48: 45 16.38 5 32.71 12:26: 15 16.38 n 32.80 lOi 10:33 16.30 5 32.37 i 10: 40: IS 16.30 3 32.71 lOi 1O:3O 16.38 5 32.57, 12:24: 15 16.38 5 32.78 f 10:47:45 16.38 3 32.72 12:22: 15 i6.ro 3 32.77 lOi 10t23 16.30; 3 32.57 10: 47: 15 16.30 3 32.72, 10: 10:20 16.30 i 5 32.50 ' 12i20: 15 16.30 3 32.78 ! 10: 46: 45 16.30 S 32.73 • I2i 1B« 15 16.3S lOi LOi IS lfe.30[ 3 ' 32. SO S 32. 7B . • i L 0 : 4 6 1 Its , 16.38 S 32.74 j 12i 16: IS • Ife.JQ 10: 1O: 1O 16.38 ' D 32.37 t a 32.7B\ ' i 10:45:43 16.38 5 32.75' 12: 14: 13 16.38 S 32.78\ lOilOtOS 16.38 S 32.50 1 • 16.38 . 5 32.70| lOilOtOO • 16.30 . 5 32.58 lOi 45: IS 12:12:13 16.38 3 32. 7O! j 1O:44: 45 16.38 5 32.70J 12: 10: 15 16.30 5 32.78; lOi07iB3 16.38 S 32.50 16.38 5 -32.7O: 10: 07: SO i 10:44t 15 12:08: 15 16.38 ,3 32.77; .16.-3B 5 32.50 10:43:45 16.38 3 32.70 !OtO7i4S 16.30. 3 ' 32.50 12:06: 15 16.38 ;s 32.77 • 10:43: 15 16.30 5 32.70 12:01: IS 16.38 S 32.78 10:07i40 • 16.38 5 32.50 1 16.30 S > 32.70 UOiO7i33 ' 16.38 S ' 32.50 10:42:45 12:02: 15 16.38 5 32.78- i 10: 42: 15 16.30 .5 j 32. 7O. 12:00:13 16.38 S 32.781 ',10107:30 16.38 5 32.38 1 10:41:45 16.38' 3 ] 32. 70 1 1:58: 13 16.38 S 32.78 ,10107:25 16.38 5 32.5(3 10:41: 15 16.30 . 3 32.7O,1 ,10i07i20 16.30 5 32.38 11:56: 15 16.38 S 32.78! 10:40:43 16.38 5 32.67: 11:55: 15 16.38 3 ' 32.78 Il0i07i IS 16.30 5 32.38 10:40: IS 16.38 S 32.70. >10i07i 10 16.38 -5 32.58 1 1:54: 15 16.38 S 32.78 10:37:45 16.38 - 5 32.67 1 1:53: 15 16.38 5 32.70 !lO:07iOS 16.38 3 32.37 10i.37tlS 16.30 5 32.6? 10107:00 16. 3B S 32. 5O 11:52: 15 16.38 3 32.78 10:38:45 16.30 5 32.6? 11:51:15 16.38 5 32.78: 110:00:53 16.30 5 32.30 10:38: 15 16.30 S 32.67 10:00:50 16.30 5 32.58 1 :50:r.i 16.38 3 32.78: • 10:37:45 16.38- 5 32.67 1 : 47: 13 16.38 •3- -32.78; 10:00:43 16.30 5 32.30 10:37:15 16.38 S 32.68 10:08:40 16.311 3 32.58 1 i 18i IS 16.30 3 32.78 '• 10:36:45 16.38 S 32.67 1 :47:15 16. 3O S 32.78 |10i08i33 16.30 S 32.57 • 10:36:13 16.38. 5 32.68 110:08:30 16.30 3 32.57 1 146:15 16.38 S 32.78 •' 10:35:40 16.38 S 32.68 1 :43:15 16.38 5 -32.7BJ J10i08t25 •16.30 3 32.57 ; 10:33: 15 16.30 5 32.68 10:08:20 16.38 5 32.57 1 :44:15 16.38 S 32.78 : l 10: 34: 45 16.38 S 32.60 1 :43:13 16.38 •S '32.78 10:00: IS 16.30 5- 32.37 • 10:34:15 16.30 S 32.68 lOiOB: 10 16.30 3 32.57 1 1:42: 15 16.38 3 32.78 i 10:33:45 ' 16.38 3 ' 32. 6U 11:41:15 16.38 ' S 32.77 10:00:03 16.30 5 32.37; | 10:33:15 16.38 S 32.68 10:08: 00 16.30 3 32,371 Ilt40: IS 16.38 5 32.77 10:32:45 .16.38 ' S 32.67 1 1:37: 15 16.38 . S 32.77 10i07i55 16.38 3 32.57 10:32:15 16.38- 3 32.67 KM 07i 50 16.38 5 32.57 i 1 1:30: 15 16.38 5 32.77 i 10:31:45 * 16.38 S 32.67 • 1 1:37: IS 16.38 3 32.77 10:07:43 16.30 5 32.37 ; 10:07:40 16.30 S 32.57 10:31:15 16.30 5 32.67 1 1:36: IS •16.38 • S. 32.77 • 10*30:43 16.38 S 32.67 •16.38 10iO7t35 • 16.38 5 32.57 \ 11:35: 15 S •'32.77 10IO7I30 16.38 5 32.57 i 10:30:13 16.30 3 32.671 11:34: IS 116.38 ' S • 32.77 10:07:23 16.3O S 32.57 10:27:43 16.38 S 32.67 11:33: IS \tb.3U 5 32.77 KM 27: la 16. 3D S 32.66 ll:32i IS M6.3U S 32.77 O I O7 1 2O 16.311 G 32.5V i 10:07:15 16.30 . 5 32.56 10:28:43 16.38 3 32. A6. 1 J : 3 1 : 1 5 16. -39.• 5 32. 77 10:07: 1O 16.38 5 32.56 i 1O:20: 15 16.38 3 32.66J 11:30: 13 • 16.38•'.3 32.77 10t07iOS 16.30 S 32.56 i 10:27:45 16.38 S 32.661 1 1:27: 13 16.38 . 5 '32.76 10tO7iOO , 16.38. 5 32.56 10:27: 15 16.38 5 32.63 • Ui28: 13 • 16.38. S 32.77 10:26:43 16.38 S- 32.66 9b 191061 55 16.38 3 32.56 : 10:06:50 16.38 5 32.56 . . 10:26: 15 16.38 5 32.63 10:06:45 16.30 S .32.56 10:26lOO 16.38 5 32.63 10i06i40 16.38 5 132.56 « 10:25:43 16.38 3 32.65 10:06i33 16.38 S -32.36 10:23:30 16.38 3 32.65 10:06:30 16.38 3 • 32.56 10:23:13 16.38 S 32.63 10:06:25 16.30 • 5 32.36 10:23:00 16.38 3 32.65 10:06:20 16.30 5 32.53' 10:24:43 16.30 S 32.65 ' 10:06: 13 16.30 S 32.36 10:24:30 16.38 5 32.63 •J 10:06:12 16.38 5 32.53 10:24:13 16.38 S 32.64 10:24:00 16.38 U 32.64 I 10:06:07 16.38 5 , 32.33; 1 10t06:06 16.38 0 32. 53i lOi 23t 45 16.33 S 32.64 *i :10i23t30 16.38 S 32.64 10:06:03 16.38 S 32.33 ' 10:23:13 16.38 5 32.64 10:06:00 16.30 5 32.53 |l ' | 10:23:00. 16.38 S • 32.64 10:03:37 16.38 S • 32.53 1 10:05:54 16.38 . S 32.55 -! ' 10:22:43 . 16.38 S 32.64 10:22:30 16.38 5 32.64 10i03:51 16.38 3 . 32.53 i 10:03:48 16.30 ,5 32.35 10:22: IS 16.38 S 32.64 10i05«43 16.30 3 32.53 ,10:22:00 16.38 3 32.64 10:05:42 16.30 3 32.55 i: ' 8b 10:03:37 16.30 3 32.56 10:03i 36 16.30 5 32.55 10:05:33 16.30 5 32.53 10:03:30 16.30 3'_!2._S3 32.53J Channel 1 lor Municipal Well 6 Channel 6 for Municipal Well 4 7b APPENDIX D

PUMPING TEST PLOTS

REPT4/tdg r L. c

r L; B D D 0 n

u - D

1 III In" Illli:'"iT-n Hi-i-n^ m 'ni" l tin' "i'iij' D iiiTiiiiT7777nintiiMiiiTintTiiiiitiiiji a .01 .1 10 100 1000 a Time (min.) ,TT LOGARITHMIC 3x3 CYCLES K-2 A USU CO.-WCurfL . 46 7522

• Municipal Welt 4 (Pumping Well)

4 967891

-, .!:. .Ji^.-.^ ^- I: - .1-1 ...-I:. U I ..TMJK .a 1-.I :l .!].. alj :. :.: I. K , .U .:.: .. -^

\ |||=|:^:Aj't^

G rr —! i i i i _ . _ i—_;__! . i i i i i i i

G 10 1 c S (ft.) * L n

.01 .1 10 100 1000 1 Time (mm.)

1 Li C LOGARITHMIC 3x5 CYCLES K Z KCUFTO. ft csscnca KMCWIIO. 46 7522 467522 n

Municipal Well 5 (observation well)

4 S 6 7 8 9 1 « S 6 7 8 9 1

un s cm c 5^5iEJym?S;Uaa o;

.01 .01 .1 '10 100 1000

Time (min.) SEMI-LOGARITHMIC 4 CYCLES X 70 DIVISIONS K-S Kcurro. * osu co. IUM » «u. Municipal Well 5 (observation well) 46 6013

.25

1.50

1.75 .01 10 100 100O

Time (mln.)