First Five Year Review Report Macalloy Corporation

First Five-Year Review Report

Macalloy Corporation National Priorities List Site Cfiarfeston, Charleston County, South Carolina

Prepared By:

U.S. EPA Region 4 Superfund Division 61 Forsyth Street, SW Atlanta, GA 30303

June 24, 2010

10760299 First Five-Year Review Report Macalloy Corporation National Priorities List Site Charleston, Charleston County, South Carolina

Prepared By:

U.S. EPA Region 4 Superfund Division 61 Forsyth Street, SW Atlanta, GA 30303

June 24, 2010

Approved by: Date: (jli M mklin E. Hill, Director Superfund Division US EPA Region 4 Table of Contents

EXECUTIVE SUMMARY viii

1. INTRODUCTION XI

2. SITE CHRONOLOGY 2

3.0 BACKGROUND 4 3.1 Physical Characteristic 4 3.2 Land and Resource Use 4 3.3 History of Contamination 5 3.4 Initial Response 5 3.5. Basis for Taking Action 7 3.5.1 Summary of RI Conclusions by Media 7 3.5.2 Summary of Site Risks 8 3.5.2.1 Human Health Risks 8 3.5.2.2 Ecological Risks 9 3.5.2.3 Fate and Transport Summary 10

4.0 REMEDIAL ACTIONS ; 12 4.1 Radiological Material: Excavation and Offsite Disposal 13 4.1.1 Remedy Selection 13 4.1.2 Remedy Implementation 13 4.1.3 Operation and Maintenance 14 4.2 Zone A Sediment Removal 14 4.2.1 Remedy Selection 14 4.2.2 Remedy Implementation 15 4.2.3 O&M 16 4.2.3.1 001 Tidal Creek Cap Monitoring 16 4.2.3.2 Tidal Marsh Plant Surveys 17 4.2.4 Five-Year Costs 18 4.3 Zone C Sediment 18 4.3.1 Remedy Selection 18 4.3.2 Operationa & Maintenance (O&M) 18 4.3.3 Five-Year Costs 19 4.4 Groundwater: Enhanced In Situ Chemical Reduction 19 4.4.1 Remedy Selection 19 4.4.2 Remedy Implementation (2004-2005) 20 4.4.3 Supplemental Remedy Implementation (2008) 22 4.4.4 O&M 24 4.4.5 Five-Year Costs 26 4.5 Soil: Onsite Chemical Reduction 26 4.5.1 Remedy Selection 27 4.5.2 Remedy Implementation 27 4.5.3 O&M 31 4.6 Surface and Storm Water: Comprehensive Storm Water Management 31 4.6.1 Remedy Selection 31 4.6.2 Remedy Implementation 31 4.6.3 O&M 33 /// 4.6.4 Five-Year Costs 33

4.7 Institutional Controls 33

5.0 PROGRESS SINCE THE LAST REVIEW 34

6.0 FIVE-YEAR REVIEW PROCESS 35 6.1 Administrative Components 35 6.2 Community Notification & Involvement 35 6.3 Document Review 36 6.4 Data Review 36 6.4.1 Review of Groundwater Monitoring Data 36 6.4.2 Review of 001 Tidal Creek Cap Measurements 38 6.4.3 Review of Tidal Marsh Plant Survey Data 38 6.4.4 Review of Zone C Sediment Monitoring Data 39 6.5 Site Inspection 39 6.6 Interviews 40 7.0 TECHNICAL ASSESSMENT 41 7.1 Question A: Is the remedy functioning as intended by the decision documents?... 41 7.1.1 Radiological Material 41 7.1.2 Zone A Sediment Removal 42 7.1.3 Zone C Sediment 43 7.1.4 Groundwater 43 7.1.5 Soil 45 7.1.6 Surface Water/Storm Water 46 7.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and RAOs used at the time of the remedy selection still valid? 46 7.2.1 Changes in Standards and To Be Considered (TBCs): 47 7.2.2 Changes in Exposure Pathways: 47 7.2.3 Changes in Toxicity and other Contaminant Characteristics: 48 7.2.4 Changes in Risk Assessment Methods: 48 7.2.5 Expected Progress towards Meeting RAOs: 48 7.3 Question C: Has any other information come to light that could call into question the protectiveness of the remedy? 50 7.4 Technical Assessment Summary 50

8.0 ISSUES 51

9.0 RECOMMENDATIONS AND FOLLOW-UP ACTIONS 53

10.0 PROTECTIVENESS STATEMENT 55

11.0 NEXT REVIEW 54

/I/ Tables

Table 2-1 Chronology of Events Table 4-1 Zone A Tidal Creek O&M Costs Table 4-2 Zone C Sediment Monitoring Costs Table 4-3 Supplemental Permeable Reactive Barriers Dimensions and Components Table 4-4 Chronology of Post-Construction Groundwater Events Table 4-5 Groundwater Monitoring and Remedial Costs during the First Five-Year Review Period Table 6-1 Groundwater Monitoring Results during the First Five-Year Review Period Table 6-2 Tidal Creek Cap Thickness Measurements during the First Five-Year Review Period Table 6-3 Zone C Sediment Monitoring Results during the First Five-Year Review Period Table 8-1 Issues Table 9-1 Recommendations and Follow-up Actions

Figures

Figure 3-1 Site Map Figure 3-2 Site Condition Before Remedial Action Figure 4-1 Site Remedies Figure 4-2 Monitoring Locations Figure 4-3 Zone C Sediment Sample Locations Figure 4-4 Rathall Creek Sediment Sample Location Figure 4-5 Storm Water Management Plan Figure 6-1 Total Chromium in Groundwater during First Five-Year Review Period Figure 6-2 Event 9 Shallow Groundwater Elevation Contours Figure 6-3 Year 4 Tidal Creek Cap Thickness Measurements Figure 7-1 Total Chromium Isoconcentration Lines Above Cleanup Goal From October 2009 Groundwater Sampling

Appendices

Appendix A Termination of Storm Water Monitoring Letter from South Carolina Department of Health and Environmental Control Appendix B Restrictive Covenant Appendix C Community Notification Appendix D Five-year review Document List Appendix E Photographs of Tidal Marsh Before and After Full Restoration Appendix F Five-year review Site Inspection Checklist Appendix G Photographs of Site during Site Inspection List of Acronyms

Mg/L Micrograms per liter

Ashley II Ashley II of Charleston, LLC bgs Below ground surface

CaS4 Calcium Polysulfide CERCLA Comprehensive Environmental Response Compensation and Liability Act CY Cubic yard

DPT Direct Push Technology

EPA United States Environmental Protection Agency ERA Ecological Risk Assessment

FRAR Final Removal Action Report FS Feasibility Study

lbs Pounds LFA Lake fill area

M Molar MCL Maximum contaminant level mg/kg Milligrams per kilograms

NPDES National Pollutant Discharge Elimination System NPL National Priorities List

O&M Operation and Maintenance OCRM Ocean and Coastal Resource Management

PCOR Preliminary Closeout Report PRB Permeable Reactive Barriers PRP Potential Responsible Party PSI Per square inch

QAPP Quality Assurance Project Plan

RAO Remedial Action Objective RCRA Resource Consen/ation and Recovery Act

RD Remedial Design redox reduction/oxidation RFI RCRA Facility Investigation RI Remedial Investigation ROD Record of Decision

w Acronyms (cont'd)

SCDHEC South Carolina Department of Health and Environmental Control Site Macalloy Corporation National Priorities List Site SPLP Synthetic Precipitation Leaching Procedure

TBCs To be considered

USI Unlined surface impoundment

VII Executive Summary

The United States Environmental Protection Agency (EPA), Region 4 Office, has prepared this First Five-Year Review Report for the Macalloy Corporation National Priorities List Site (NPL), ID #SCD003360476, located at 1800 Pittsburgh Avenue in Charleston, South Carolina. The site was used to manufacture ferrochromium alloy from 1941 to 1998 by several companies and, at various times the Department of Defense, with submerged or open arc furnaces. Waste materials generated during furnace operations included slag, wastewater, airborne waste gases, and particulate matter that were stored in unlined and lined impoundments throughout the site. The site is approximately 140 acres fronting Shipyard Creek in an industrial and commercial section of the Charleston Peninsula, which is formed by the confluence of the Ashley and Cooper Rivers. Currently, several industrial businesses occupy the southern portion of the site, and an inter-modal shipping facility is planned for the northern portion with Shipyard Creek access.

During its final years of operation the plant was regulated by several federal environmental statues, primarily the Clean Water Act, the Clean Air Act, and the Resource Conservation and Recovery Act. After production at the plant ceased in July 1998 Macalloy, the EPA, and South Carolina Department of Health and Environmental Control (SCDHEC) decided the Comprehensive Environmental Response Compensation and Liability Act would be a more appropriate mechanism for the site. Subsequently, it was listed on the NPL in February 2000. Upon completion of a Phase I and II Remedial Investigation and Feasibility Study, the EPA published the Record of Decision (ROD) on August 21, 2002, for the cleanup of contaminated soil, groundwater, storm water, and sediment at the site. The following remedial action objectives (RAOs) were established by the Final ROD:

• Prevent future site worker exposure to unacceptable hazard levels in groundwater.

• Remediate shallow groundwater zones with the highest concentrations of hexavalent chromium to minimize long-term threats and limit hexavalent chromium migration into Shipyard Creek.

• Remediate soil that leaches hexavalent chromium to groundwater and surface water at concentrations hazardous to human health and the environment.

• Mitigate offsite hexavalent chromium discharges in storm water to Shipyard Creek through a combination of the aforementioned remediation measures and a comprehensive site-wide storm water management plan.

• Manage storm water discharges of toxic inorganic compounds in accordance with the comprehensive storm water management plan to protect ambient saltwater quality in Shipyard Creek.

• Remediate soil and debris that produce elevated levels of gamma radiation to mitigate current exposure pathways.

• Mitigate exposure of benthic organisms to contaminated sediments in the Outfall 001 Tidal Creek.

VIII To accomplish these RAOs, the following comprehensive, site-wide remedy was specified in the ROD and is summarized below.

Environmental Media Remedy Component Description Radiological Material Excavation with Offsite Disposal 001 Tidal Creek: Removal, Upland Disposal, Capping Sediment & Restoration Zone C Shipyard Creek: Monitoring up to Five-Year Review Groundwater Enhanced In Situ Chemical Reduction Soil Onsite Chemical Reduction Surface Water/Storm Water Comprehensive Storm Water Management System Institutional controls and restrictive covenants to limit land use to commercial/industrial purposes, and Multi-media prohibit the use of groundwater underlying the property

Remedial action design documents and work plans were completed and approved between January 2003 and September 2004. Construction activities for the comprehensive, site-wide remedy began on October 11, 2004, and were considered complete in accordance to the ROD upon signing of the Preliminary Close-Out Report on September 26, 2006.

The remedy at the Macalloy Site currently protects human health and the environment in the short- term because the following were completed to meet RAOs:

• Radiological debris and soil was removed.

• Contaminated sediment in Zone A was removed and a clean sand cap was constructed to isolate the minimal deeper contaminants.

• Concentrations of hexavalent chromium in soil were reduced below 23 milligrams per kilograms.

• A comprehensive storm water management system was constructed to mitigate offsite storm water discharges of toxic inorganic compounds.

• Institutional controls and restrictive covenants were executed for the Site that limit future use to commercial/industrial purposes, and prohibit the use of groundwater underlying the property.

The soil and ongoing groundwater remedy have reduced the highest concentrations of hexavalent chromium in the shallow groundwater; however, in order for the remedy to be protective in the long-term, monitoring well MW054R needs to be evaluated and all site shallow groundwater must show sustained concentrations of hexavalent chromium below the cleanup goat of 100 micrograms per liter.

IX Five-Year Review Summary Form

SITE IDENTIFICATION Site name (from WasteLAhJ): Macalloy Corporation NPL Site EPA ID (from WasteLAN): SCD003360476 Region: 4 State: SC City/County: Charleston, Charleston County SITE STATUS NPL status: ^ Final QDeleted nother (specify) Remediation status (choose all that apply): G Under Construction G Operating ^ Complete Multiple OUs?* G YES ^NO Construction completion date: 9 1261 2006 Has site been put into reuse? ^ YES G NO

REVIEW STATUS Lead agency: ^EPA G State G Tribe G Other Federal Agency Author name: Craig Zeller, P.E. Author title: Remedial Project Manager Author affiliation: US EPA R4 - Superfund Div. Review period: October 2009 to June 2010 Date(s) of site inspection: 10/16/2009 Type of review: ^ Post-SARA n Pre-SARA D NPL-Removal only I I Non-NPL Remedial Action Site n NPL State/Tribe-lead I I Regional Discretion

Review number: ^ l (first) D 2 (second) D 3 (third) D Other (specify) Triggering action: 1^ Actual RA Onsite Construction D Actual RA Stan at 0U# 1 I I Construction Completion I I Previous Fivc-Ycar Review Report • Other (specify) Triggering action date (from WasteLAN): 10/11/2004 Due date (five years after triggering action date): 10/11 /2009 Five-Year Review Summary Form (cont'd.)

Issues: Zone A 001 Tidal Creek Cap: One small section of the sand cap was repaired and an increasing number of transects with thicknesses less than 18 inches have been observed each year. O&M was recommended during the second five-year period to monitor and maintain the protectiveness of the remedy.

Tidal Marsh Plant Surveys: Stem density surveys of the hand-planted grass in the disturbed tidal marsh were effective in evaluating the status of restoration. OCRM success criteria for plant restoration have been met; therefore, no future monitoring is recommended.

Zone C Sediment Monitoring: During the five-year review period, concentrations of total metals in October 2009 were below protective ranges established by the FRAR and toxicity tests resulted in no adverse effects to benthic organisms; therefore, no additional monitoring is recommended for Zone C.

Groundwater- Monitoring Optimization: During the October 2009 First Five-Year Site Inspection, SCDHEC and EPA recommended groundwater monitoring to continue semi-annually for the next two years and then annually for the following three years until the second five-year review. Monitoring wells MW049, MW050, MW051 and MW059 have consistently demonstrated concentrations of chromium below the cleanup goal.

Groundwater- MW054R: Elevated concentrations of total chromium above the groundwater cleanup goal were reported at MW054R, during Event 8 in April 2009. This well could not be re-sampled, nor concentrations verified during Event 9 sampling in October 2009 as the well was obstructed with road fill. MW054R is located on property owned by Sonoco. This property contains deed restrictions that require Sonoco to be respectful of the remediation system.

Groundwater- Well Surveys: A horizontal and vertical professional coordinate survey has not been performed for wells MW054R, MW056, MW057R, and MW058. This data is needed to adequately determine groundwater elevations and flow direction on the site.

Surface Water/ Storm Water Management System: During the site inspection, it was noted that vegetation in the storm water ponds and ditches were overgrown, obscuring the evaluation of sediment buildup.

Recommendations and Follow-up Actions:

Zone A 001 Tidal Creek Cap: Monitor cap thickness in 2011 and 2013

Tidal Marsh Plant Surveys: Completed/ Discontinue

Zone C Sediment Monitoring: Completed/ Discontinue

XI Groundwater- Monitoring Optimization: Continue long term effectiveness groundwater monitoring on semi­ annual basis for next two years and then annually thereafter, depending on results. Monitoring wells MW049, MW050, MW051, MW052 and MW059 will be dropped from the long-term monitoring network, but will not be abandoned at this time in case additional samples are required in the future. The following 16 monitoring wells are recommended for the sampling network: MW040 to MW048, MW054R, MW055, MW056, MW057R, MW060, MW061, and MW062.

Groundwater- MW054R: Locate, assess condition, and re-sample MW054R if possible. Raise flush mount casing to accommodate future road elevation changes. MW054R is located on property owned by Sonoco. This property contains deed restrictions that require Sonoco to be respectful of the remediation system. The costs to find, and potentially repair MW054R should be the responsibility of Sonoco.

Groundwater- Well Surveys: Attain a horizontal and vertical professional coordinate survey of MW054R, MW056, MW057R, and MW058.

Surface Water/ Storm Water Management System: Evaluate vegetation and sediment buildup in the storm water management system and clean if necessary.

Protectiveness Statement: The remedy at the Macalloy Site currently protects human health and the environment in the short-term because the following were completed to meet RAOs: • Radiological debris and soil was removed. • Contaminated sediment in Zone A was removed and a clean sand cap was constructed to isolate the minimal deeper contaminants. • Concentrations of hexavalent chromium in soil were reduced below 23 mg/kg. • A comprehensive storm water management system was constructed to mitigate offsite storm water discharges of toxic inorganic compounds. • Institutional controls and restrictive covenants were executed for the Site that limit future use to commercial/industrial purposes, and prohibit the use of groundwater underlying the property.

The soil and ongoing groundwater remedy have reduced the highest concentrations of hexavalent chromium in the shallow groundwater; however, in order for the remedy to be protective in the long-term, monitoring well MW054R needs to be evaluated and all site shallow groundwater must show sustained concentrations of hexavalent chromium below the cleanup goal of 100 pg/L.

XII First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

1.0 Introduction The purpose of five-year reviews is to determine whether the remedy at a site is protective of human health and the environment. The methods, findings, and conclusions of reviews are documented in Five-Year Review reports. In addition, Five-Year Review reports identify issues found during the review, if any, and recommendations to address them. The Agency is preparing this Five-Year Review pursuant to Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) §121 and the National Contingency Plan. CERCLA §121 states:

If the President selects a remedial action that results in any hazardous substances, pollutants, or contaminants remaining at the site, the President shall review such remedial action no less often than each five years after the initiation of such remedial action to assure that human health and the environment are being protected by the remedial action being implemented. In addition, if upon such review it is the judgment of the President that action is appropriate at such site in accordance with section [104] or [106], the President shall take or require such action. The President shall report to the Congress a list of facilities for which such review is required, the results of all such reviews, and any actions taken as a result of such reviews.

The agency interpreted this requirement further in the National Contingency Plan; 40 CFR §300.430(f)(4)(ii) states:

If a remedial action is selected that results in hazardous substances, pollutants, or contaminants remaining at the site above levels that allow for unlimited use and unrestricted exposure, the lead agency shall review such action no less often than every five years after the initiation of the selected remedial action.

The United States Environmental Protection Agency (EPA), the Macalloy Potential Responsible Party (PRP) Group, and the South Carolina Department of Health and Environmental Control conducted this First Five-Year review of the remedial actions implemented at the Macalloy Corporation National Priorities List (NPL) site in Charleston, South Carolina (Site). The triggering action for this statutory review was the start of remedial action which began on October 11, 2004. Five-Year Reviews for this Site are required by statute due to the presence of hexavalent chromium in groundwater underlying the Site that does not allow for unlimited use and unrestricted exposure. This review was conducted from October 2009 through May 2010. This report presents the results of the review. First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

2.0 Site Chronology The following table summarizes the primary milestones and relevant dates in the site chronology.

Table 2-1 Chronology of Events Date Event March 25, 1998 Discovery June 6, 1998 to November 4, 1999 PRP Removal Action June 13, 1998 Administrative Order on Consent for Removal Action October 22, 1999 Proposal to the National Priorities List (NPL) November 15, 1999 Preliminary Assessment Completed February 4, 2000 Final Listing on the NPL Administrative Order on Consent signed for Remedial Investigation/ March 29, 2000 Feasibility Study March 29, 2000 to August 21, 2002 PRP-lead Remedial Investigation/Feasibility Study August 21, 2002 Record of Decision Signed January 10, 2003 Final Pre-Design Sampling and Analysis Report Submitted January 13, 2003 Final Treatability Study Report Submitted September 4, 2003 Remedial Design Submitted/Approved December 2003 Groundwater and Soil Sampling Results Memorandum Submitted (Presents the results of additional delineation and May 13, 2004 lithologic sampling required by the remedial design) June 14, 2004 Remedial Action Consent Decree Entered September 2, 2004 Remedial Action Kick-Off Meeting September 24, 2004 Final Sediment Remedial Action Work Plan Submitted October 11, 2004 Mobilization to Site October 12, 2004 Injection Wells and Monitoring Wells Installation Began October 4, 2004 Final Soil Remedial Action Work Plan Submitted November 4 to 16, 2004 Baseline Groundwater Sampling Conducted November 14 to March 5, 2005 Reductant Injections December 6 to 23, 2004 001 Tidal Creek Sediment Removal December 27, 2004 to January 29, 2005 001 Tidal Creek Geotextile Installation and Sand Cap Placement January 20, 2005 Storm Water Discharge Limitations Memorandum Submitted Februar/ 1 to 12, 2005 Soil Treatment Demonstration February 7 to 9, 2005 Radiological Material Removal March 1, 2005 Soil Remediation Starts March 11 to 13, 2005 001 Tidal Creek Marsh Restoration First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Table 2-1 Chronology of Events September 10, 2005 Site Clearing for Storm Water System Construction Began October 11 to 12, 2005 Redox Trench Pilot Study October 31, 2005 Complete Soil Remediation December 2 to 20, 2005 Redox Trenches Installed December 6, 2005 Low Carbon Slag Discovery December 21, 2005 to Januar/ 17, 2006 Low Carbon Slag Delineation January 28 to March 30, 2006 Low Carbon Slag Removal and Stockpiling July 5, 2006 Low Carbon Slag Treatment July 13, 2006 Pre-Final Walk-Through and Inspection July 20, 2006 Punch List for Remedial Construction Complete August 7, 2006 Interim Final Walk-Through and Inspection August 9, 2006 August 7, 2006 Site Inspection Punch List August 21 to August 29, 2006 Installation of Long-Term Monitoring Wells September 18, 2006 Final Walk-Through Inspection September 26, 2006 Preliminary Close-Out Report signed July 16, 2008 SCDHEC Terminated Storm Water Sampling Requirements December 2008 Repair of 001 Tidal Creek Cap December 2008 Supplemental Groundwater Treatment First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

3.0 Background Physical characteristics, land and resource use, history of contamination, initial response actions and a basis for remedial action for the Site are provided in the following sections.

3.1 Physical Characteristics The Macalloy Corporation NPL Site, EPA ID #SCD003360476, is located at 1800 Pittsburgh Avenue in Charleston, Charleston County, South Carolina. The Site is a former ferrochromium alloy manufacturing plant situated on approximately 140 acres fronting Shipyard Creek in a highly industrialized and commercial section of the Charleston Peninsula, which is formed by the confluence of the Ashley and Cooper Rivers. The Site is directly adjacent to a tidal creek and marsh along Shipyard Creek. Figure 3-1 presents a map of the current configuration of the Site.

Two roads (Sewanee Rd. and Talluah Rd.) built in 2007 divide the Site into approximately 110 acre and 30 acre portions. The northern portion consists of approximately 110 acres of undeveloped land vegetated with grass and shrubs. The southern portion is approximately 30 acres in size and is currently occupied by several light industrial/commercial businesses.

The topography of the Site is relatively flat with elevations ranging between 10 to 15 feet above mean sea level. Earthen ditches channel onsite storm water runoff to two engineered settling basins. Permitted discharge primarily occurs through one National Pollutant Discharge Elimination System (NPDES) outfall, with limited areas flowing directly to Shipyard Creek. Shallow groundwater beneath the Site generally flows from west to east and toward Shipyard Creek.

3.2 Land and Resource Use Ferrochromium alloy was manufactured at the Site from 1941 to 1998. The Site was owned and operated by Pittsburgh Metallurgical Company from 1941 to 1966, Airco (British Oxygen Corporation) from 1966 to 1979, and Macalloy from 1979 to July 1998, when alloy production ceased. At various times from 1942 to 1998, the Department of Defense owned, operated, or otherwise used portions of the site to produce and store ferrochromium alloy, chrome ore, and slag (waste).

In February 2005, the Macalloy property was purchased by Ashley II of Charleston, LLC (Ashley II) while remedial action was underway. Immediately following the completion of remedial activities in 2006, Ashley II completed site improvements (road, water, sewer, improved drainage) to the Site to accommodate an industrial park. Approximately 30 acres, located in the southern portion of the Site, are currently occupied by several light industrial/commercial businesses. First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

In March 2007, Ashley II sold the property to Shipyard Creek Associates, LLC who currently intends to redevelop the Site's northern portion as a multi-modal port facility. Businesses located on the Site attain drinking water from the city water supply.

3.3 History of Contamination The ferrochromium alloy manufacturing process involved the conversion of chromium-bearing ore (chromite) to ferrochromium in a single submerged arc electric furnace. The alloy was then shipped offsite for production of high-quality stainless steel. During operation, smelting was conducted in both submerged and open arc furnaces. Open arc (low carbon) furnaces were operated from approximately 1946 to 1967. Submerged arc furnaces were used in subsequent years. Open arc furnaces generally produce more hexavalent chromium by-product than submerged arc furnaces. The submerged arc furnace yielded approximately 180 tons of finished ferrochromium per day. Final Phase I RI Report [EnSafe, April 18, 2001).

Waste materials generated during furnace operations included wastewater, airborne waste gases, and particulate matter. Water was used for cooling the furnace and as the contact cooling medium for airborne discharges from the furnace. Air emissions control equipment at the Site included three baghouses, two gas conditioning towers, and two electrostatic precipitators. These systems generated various solid wastes, including dust collected in the electrostatic precipitators and baghouses, sludge from the gas conditioning towers, and bottom sludge from an onsite NPDES permitted settling pond (former Outfall 001). From 1988 until 1997, Macalloy operated an unlined surface impoundment (USI) for treated electrostatic precipitator dust just north of the ferrochromium process area.

3.4 Initial Response During its final years of operation, the plant was regulated by several federal environmental statutes, primarily the Clean Water Act, the Clean Air Act, and the Resource Conservation and Recovery Act (RCRA). In 1992 the South Carolina Department of Health and Environmental Control (SCDHEC), Bureau of Water Pollution Control issued Administrative Order 92-64-W requiring the Macalloy Corporation to remediate hexavalent chromium contaminated groundwater on the property. Pursuant to this order, a pump and treat groundwater remediation system was installed around the USI in 1994 and 1995. In 1996 Macalloy began the RCRA corrective action process. In January 1997 pursuant to the terms of a consent order with SCDHEC (No. 96-38-HW), Macalloy initiated offsite disposal of treated ESP dust from the USI. First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

In June 1998 Macalloy and EPA entered into a Removal Action Administrative Order on Consent to address potential releases via storm water runoff of hazardous substances from the Macalloy plant to Shipyard Creek. To comply with the order, a storm water management system was constructed that consisted of a series of earthen berms, ditches, and detention basins that collected onsite and offsite surface water. Two outfalls discharged storm water from the Site to Shipyard Creek. Surface water discharge samples collected from October 1998 to September 2000 indicated hexavalent chromium exceeded the NPDES limits. Additionally, arsenic, copper, lead, and zinc were identified as constituents of concern based on analytical results associated with surface water samples collected at the Site's discharge point to Shipyard Creek. A preliminary ecological risk evaluation was performed by EPA during installation of the surface water management system.

In October 1998 an initial Draft RCRA Facility Investigation (RFI)/Confirmation Sampling Investigation Work Plan (EnSafe, November 1999), was submitted to EPA and SCDHEC for review and comment. The initial draft RFI work plan was revised based on technical comments received from both agencies, and then resubmitted to the appropriate regulatory agencies on November 30, 1999.

Plant operations ceased in July 1998; at this time, Macalloy, EPA, and SCDHEC decided that the CERCLA would be a more appropriate regulatory mechanism for this Site. Subsequently, the Site was proposed for inclusion on the NPL on October 22, 1999, and was listed as "final" on February 4, 2000. On March 29, 2000, Macalloy entered into an Administrative Order on Consent with EPA to perform a CERCLA Remedial Investigation/Feasibility Study (RI/FS). The revised November 30, 1999 RFI Work Plan (EnSafe, 1999), formed the basis of the CERCLA RI/FS work plan, which was converted to fulfill the requirements of the March 29, 2000 agreement with EPA. EPA approved the RI/FS Work Plan as final on June 1, 2000.

In December 2000, the first phase of the RI was completed under oversight by EPA and SCDHEC. During the first phase of the RI, the onsite nature and extent of soil and groundwater contamination was assessed and associated risks to human health and the environment were evaluated. Field activities and findings were documented in a Final Phase I RI Report {EnSafe, April 2001), which was approved by the EPA on May 17, 2001. The Phase I RI Report concluded that several data gaps needed to be filled before an FS could begin. Therefore, a second phase of the RI was conducted in June 2001, to further assess risks to human and ecological receptors from potential contamination in Shipyard Creek. Field activities and findings were documented in a Final Phase II RI Report {EnSafe, January 2002), which was approved by the EPA on March 21, 2002. First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

3.5. Basis for Taking Action Based on the findings of the comprehensive RI, historical operations at the Site impacted soil, groundwater, surface water, and sediment. The following sections provide the basis for taking action at the Site by summarizing the RI and risk assessment conclusions, contaminants of concern, and the primary health threats. Figure 3-2 provides a map of site features and conditions prior to remedial action.

3.5.1 Summary of RI Conclusions by Media Soil Approximately 60,000 cubic yards of site soil was determined to be impacted by hexavalent chromium. Soil impacted by hexavalent chromium was observed from the ground surface to approximately 15 to 20 feet below ground surface (bgs) and determined to be concentrated in and around the Marsh Lake Fill Area (LFA), the former furnace buildings, the former concentrator area, and other isolated locations across the Site. These areas were filled with material from plant operations, including raw materials, slag, sludge, and treated and untreated dust from air pollution control equipment. An additional 55,000 cubic yards of onsite material used as berm material for surface impoundments also contained elevated concentrations of hexavalent chromium.

Approximately 110 cubic yards of soil and debris with gamma radiation levels greater than background levels were identified near the former concentrator area. The radionuclides detected were radium-226, thorium-232, potassium-40, and uranium-235. This material is believed to have been brought to the Site in railcars carrying feedstock for alloy production. The average depth of the radiological debris was determined to be 18 inches.

Groundwater Five plumes of groundwater contaminated with hexavalent chromium were identified at the Site during the RI. The largest of the plumes. Plume I extended approximately from the former USI to Shipyard Creek. Hexavalent chromium concentrations of 10,000 micrograms per liter (pg/L) were measured in Plume I. Plumes II, III, and IV were smaller in size and located immediately adjacent to the eastern edge of Plume I. Plume V was identified at the plant's former concentrator area. Data collected during the RI, indicated that impacted groundwater at each of the plumes was confined to the shallow aquifer and did not penetrate a clay confining layer that exists across the Site, at approximately 20 feet bgs. First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Surface Water Surface water samples associated with the Site's storm water management system exceeded the hexavalent chromium limit at several sampling locations. Other metals including arsenic, copper, lead, and zinc were identified as being a concern due to offsite discharge to Shipyard Creek.

Sediment Results of a site-wide Ecological Risk Assessment (ERA) concluded that sediment in 001 Tidal Creek Zone A of Shipyard Creek, formerly an outfall for onsite surface water discharging to Shipyard Creek, contained elevated levels of total chromium, nickel, and zinc. The tidal creek is approximately 1,070 feet long and varies from 15 feet to 60 feet wide. The volume of contaminated sediment was estimated to be 1,000 cubic yards to a depth of 18 inches.

3.5.2 Summary of Site Risks As part of the RI/FS, a Baseline Risk Assessment was conducted to evaluate current and potential effects of contaminants to human health and the environment. Human health exposure pathways evaluated included ingestion, inhalation, and dermal contact with surface soils and groundwater, and ingestion of shellfish from Shipyard Creek. The EPA based its cleanup goals on an expected future industrial land use exposure scenario for an onsite worker. Groundwater ingestion was not determined to be a likely exposure pathway at the Site, since shallow groundwater is not currently used for consumption, nor will it likely be in the future. Nonetheless, shallow groundwater beneath the Site was conservatively assumed to be a source of drinking water because South Carolina classifies all groundwater as a potential underground source of drinking water.

Ecological exposure pathways evaluated included direct exposure of terrestrial and aquatic communities to site soil and Shipyard Creek sediment and surface water, as well as indirect (food-chain), exposure to species that use both habitats.

3.5.2.1 Human Health Risks Human health risk levels for potential cancer-causing chemicals are based on the concentration of the chemical and its strength as a cancer-causing agent. A risk range of lO'"* to 10"^ for the protection of human health is considered acceptable by the EPA. This range would mean an increased chance of no more than one additional case of cancer in 10,000 (lO""*) to one million (10 ^) people. Chemicals producing harmful effects other than cancer were compared with reference doses (highest levels not causing harmful effects) to calculate a hazard quotient. A hazard quotient above 1 indicates that a constituent is present at concentrations that may produce harmful effects other than cancer. First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

No chemicals of concern were identified for surface soil under the future site worker (industrial) scenario. However, hexavalent chromium was identified as a contaminant in soil that could leach to shallow groundwater at concentrations hazardous to human health. Risk and hazard calculations were overwhelmingly driven by the conservative assumption that groundwater will be used as drinking water. Hexavalent chromium in shallow groundwater accounted for 91% of the hazard associated with ingestion (hazard quotient=31). Calculated carcinogenic risk (5 xlO'^) was within the EPA's acceptable risk range. Based on groundwater data collected from deep wells installed and sampled at the Site, no chemicals of concern were identified for deep groundwater, located below the clay confining unit, under the future site worker scenario.

No chemicals of concern for shellfish ingestion were identified in the human health risk assessment, under the assumption that recreational receptors would consume equal quantities of crab, oyster, and shrimp from Shipyard Creek. Using the conservative assumption that receptors consume only shrimp harvested downgradient of Macalloy; arsenic in shrimp was the only chemical that exceeded reasonable maximum exposure hazard quotient and cancer risk values. However, calculated risk levels were within the range calculated for ingesting shellfish containing arsenic at background levels. No chemicals of concern were identified for the central tendency exposure evaluations.

A general area gamma radiation survey was performed by the EPA to evaluate the nature and extent of potential radiological contamination across the Site and the potential risk posed to the public. The survey measured elevated radiation levels (twice background or higher), in an area near the former concentrator building.

3.5.2.2 Ecological Risks During the RI/FS, risks were evaluated for ecological receptors across expected contaminant gradients in Zone A, B, and C of Shipyard Creek. Figure 3-2 shows the locations of these zones in Shipyard Creek. Sediment chemistry, acute and chronic sediment toxicity testing, grass shrimp abundance, tissue chemistry, and food-chain modeling were used to assess potential risk to ecological receptors based on a multiple lines-of-evidence approach.

Zone A comprises a small tidal creek (001 Tidal Creek) that historically received process water discharges from plant operations. Sediments within this channel contained elevated concentrations of total chromium, nickel, and zinc above protective ecological criteria and exhibited chronic effects on grass shrimp in laboratory toxicity tests. For these reasons, EPA concluded there was an unacceptable risk to the benthic community, and Zone A was retained and further evaluated in the FS. First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Results from the selected measurement endpoints demonstrated that no unacceptable risk exists in Zone B.

One measurement endpoint, embryo production, indicated unacceptable risks in Zone C. However, based on the strength and magnitude of observed adverse effects and the expectation of diminishing risks following remediation, a risk management decision was made to monitor total metals and toxicity in Zone C.

3.5.2.3 Fate and Transport Summary Soil-to-groundwater, groundwater-to-surface water, and onsite soil- and surface water-to-offsite surface water pathways and receptors were evaluated for each constituent detected at the Site. Hexavalent chromium, antimony, arsenic, trivalent chromium, and copper were identified as contaminants having potentially significant migration pathways in the RI.

Hexavalent chromium impacted soil and groundwater generally co-existed in similar areas of the Site. Hexavalent chromium groundwater concentrations also exceeded the respective surface water screening value within the plumes. The majority of the Site's impacted groundwater was determined to be located adjacent to Shipyard Creek and its' marsh. Although, hexavalent chromium was not measured in groundwater samples collected from monitoring wells installed in the vicinity of Shipyard Creek, it was determined that hexavalent chromium laden groundwater could potentially discharge to Shipyard Creek and the associated marsh. Because of the potential migration pathways for hexavalent chromium to move from soil and groundwater to surface water, hexavalent chromium was retained for further evaluation in the FS.

Antimony and arsenic exceeded site-specific screening levels and/or background concentrations in soil. Arsenic also exceeded the maximum contaminant level (MCL) and surface water screening criteria in isolated groundwater wells. However for both of these metals, no discernable groundwater plume existed at the Site and the human health risk assessment produced hazard quotients of less than 1. Antimony and arsenic were not retained for further evaluation in the FS.

Trivalent chromium exceeded its surface water screening criteria in several groundwater samples collected at the Site. However, trivalent chromium's solubility (and thus its mobility in groundwater) is very low and its presence in these samples may have been associated with solid particles remaining in the well after drilling; these solids are not mobile in groundwater. Trivalent chromium was not measured above surface water criteria in filtered groundwater samples collected from marsh wells and therefore was not retained for further evaluation in the FS. _ First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Copper in groundwater exceeded its surface water criteria in several isolated wells; however, a discernable copper plume was not identified and copper was not measured above surface water criteria in filtered groundwater samples collected from the wells in the vicinity of Shipyard Creek. Therefore, copper was not retained for further evaluation in the FS.

11 FIGURE 3-1 SITE MAP

Legend FIRST FIVE YEAR REVIEW REPORT MACALLOY CORPORATION NPL SITE -0- Long-Term Effectiveness Shallow Monitoring Well CHARLESTON, SC ^~ ~ Site Boundary Aerial Source: sen/ices.arcgisonline.com Notes: REQUESTED BY: CT Location of MW054R and IVIW057R are estimated from aerial photograph. Wells were reinstalled due to building construction. 0 150 300 600 ENSAFE HFeet

Date: 1/28/10 K:\GIS\Macalloy\Finst Five Yr Review

First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

4.0 Remedial Actions Based on the findings of the RI, a FS was conducted to develop, evaluate, and compare Remedial Action alternatives that could be used to mitigate hazards and threats to human health and the environment from impacted media. EPA approved the Final Feasibility Study Report {EnSafe, 2002) on April 2, 2002, and subsequently issued a Proposed Plan as part of its public participation responsibilities under Section 117(A) of CERCLJ^ and Section 300.430(f)(2) of the National Contingency Plan. After addressing the public comments on the Proposed Plan, the EPA prepared and published the Final Record of Decision (ROD) for the Site in August 2002.

Remedy components and selected remedies stated in the ROD were:

• Radiological Material: Excavation with Offsite Disposal

• Sediment:

Zone A 001 Tidal Creek: Removal, Upland Disposal, Capping & Restoration Zone C Shipyard Creek: Monitoring only

• Groundwater: Enhanced In-Situ Chemical Reduction

• Soil: Onsite Chemical Reduction

• Surface Water/Storm Water: Comprehensive Storm Water Management System

• Institutional Controls thru deed restriction

A Final Remedial Design (RD) (EnSafe, September 2003) for the Macalloy Site was submitted in September 2003, and a Consent Decree to conduct the remedial action was entered on June 14, 2004. The Macalloy PRP Group retained EnSafe to serve as the supervising contractor for the remedial action. ENTACT of Friendswood, Texas, was selected as the remedial construction contractor. Remedial Action, as described in bullets above, was initiated with onsite mobilization on October 11, 2004.

EPA and SCDHEC conducted a Pre-Final Inspection at the Site on July 13, 2006, an Interim Final Inspection on August 7, 2006, and a Final Inspection on September 18, 2006. Based on these inspections and review of the Final Remedial Action Report {EnSafe, September 20, 2006), EPA and

12 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

SCDHEC concluded that the Macalloy PRP Group constructed the remedy in accordance with the ROD and approved RD plans and specifications. The Site achieved construction complete status when the Preliminary Close-Out Report {?COK) was signed on September 26, 2006. The following sections present the remedy selection, remedy implementation, operation and maintenance and/or long term monitoring for each remedy component.

Figure 4-1 shows a map of site remedies presented in this Five-Year Review Report.

4.1 Radiological Material: Excavation and Offsite Disposal Debris with gamma radiation levels exceeding twice the background levels 12 micro- Roentgens/hour was identified in shallow soil near the former concentrator area in the southwestern portion of the Site.

4.1.1 Remedy Selection The following remedial action objective (RAO) was specified in the ROD for the radiological material area.

• Remediate soil and debris that produce elevated levels of gamma radiation to mitigate current exposure pathways.

The ROD proposed reducing radiation levels in soil and debris to 12 micro-Roentgens/hour. Based on the Phase II remedial investigation (EnSafe, 2002) and the evaluation of remedial alternatives during the Feasibility Study (EnSafe, 2002), removal and offsite disposal in a Subtitle D landfill was selected as the remedy for the radiological materials.

4.1.2 Remedy Implementation EnSafe subcontracted with Philotechnics, Ltd, a waste management firm specializing in radiological and mixed waste, to assist with the removal action. ENTACT, the remedial construction contractor, performed the debris removal. Removal activities began on February 7, 2005, and were completed on February 9, 2005. The radiological debris area was in the southwestern portion of the Site and covered approximately 2,025 square feet. Erosion controls were placed on the downslope sides of the removal area before construction began. Initially, the entire area was excavated to a depth of 9 inches and then soil left in place was field screened using a pressurized ion chamber. Initial screening indicated that material exceeding 12 micro-Roentgens/hours remained, thus additional material was removed followed by screening until the cleanup goal was achieved. — First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Final excavation depths ranged from 9 to 18 inches. In total, approximately 200 tons of debris and soil were excavated and transported to U.S. Ecology Idaho, Inc. in Grand View, Idaho for appropriate disposal. Upon completion of the removal activities, a confirmatory survey and inspection was performed by EPA and SCDHEC on May 11, 2005. Further documentation is provided in the Final Removal Action Report (FRAR).

4.1.3 Operation and Maintenance No operation and maintenance (O&M) was required for the radiological remedy.

4.2 Zone A Sediment Removal The results of a site-wide ERA indicated that sediment in the Zone A 001 Tidal Creek contained elevated levels of total chromium, nickel, and zinc.

4.2.1 Remedy Selection The following RAO was specified by the ROD for the sediment in the 001 Tidal Creek.

• Mitigate exposure of benthic organisms to contaminated sediments in the Outfall 001 Tidal Creek.

The ROD called for reducing benthic organisms' exposure of chromium, nickel, and zinc in tidal creek sediment by removal with upland disposal. Specifications in the ROD included the removal of the top 18 inches of contaminated sediment using dredging equipment, dewatering of the sediment, and incorporation of the sediment into the onsite soil remedy. Based on subsequent pre-design sediment sampling, which indicated that sediment contamination was present at depths ranging from 18 to 36 inches, the remedy for Zone A was modified in the Final Design as follows:

• Dredging depth of creek channel sediments was increased from 18 to 24 inches.

• A geotextile was specified to line the dredged creek channel and minimize bioturbation in the remaining contaminated sediment.

• An 18-inch clean sand cap was used to cover the geotextile.

Pre-design sampling at ten locations in the tidal creek indicated that only three locations exhibited contamination at depths greater than 24 inches. Therefore, dredging 24 inches of sediment removed most of the contamination. Concentrations of total chromium, nickel, and zinc remaining 14 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010 after dredging were contained beneath the geotextile liner and sand cap. The use of the geotextile liner and sand cap served to limit the dredging depth, without compromising the ultimate goal of protecting marine organisms.

4.2.2 Remedy Implementation Prior to construction, a Remedial Action Work Plan (ENTACT) for sediment in 001 Tidal Creek was submitted to EPA and SCDHEC for review and approval. In addition, a Critical Area Permit and Coastal Zone Consistency Certification were obtained from the SCDHEC Office of Ocean and Coastal Resource Management (OCRM). To minimize re-suspension of sediments outside of work areas, a floating turbidity barrier was installed at the mouth of the tidal creek, from one edge of the creek channel to the other, and secured with anchors. EnSafe monitored turbidity in Shipyard Creek during construction to verify that sediment re-suspension controls were effective.

Sediment removal began on December 6, 2004, and was completed on December 23, 2004. Due to access limitations, ENTACT used a combination of conventional and specialty excavation equipment to complete the removal in accordance with the work plan. The configuration of the creek and adjacent shoreline allowed ENTACT to use a conventional tracked excavator with a long- reach excavating arm to remove sediment along the first 390 feet of creek bed. The remaining portion of the creek bed was excavated using amphibious low-ground-pressure equipment, consisting of a long-reach excavator and a hauling unit capable of holding approximately 10 cubic yards. The excavator and hauling unit were mounted on twin pontoons and which achieved ground pressures in the range of 2 to 5 pounds per square inch. A cable and pulley system attached to the amphibious excavator on shore was used to pull the hauling unit to and from the excavation area via a short haul road, which intersected the creek channel. Because these activities could only take place during low tide, work was conducted during two five-hour shifts during both daily low tides. To ensure that the excavation achieved the required 2-foot depth, ground personnel directed the excavator operator and used a surveyor's rod to continuously verify excavation depths.

Geotextile installation and placement of clean sand backfill began on December 28, 2004, and was completed on January 29, 2005. Upon completion of sediment removal, geotextile fabric was placed across the excavated area and secured using 24-inch-long hooked steel reinforcing bars. Adjacent sections of fabric were overlapped a minimum of 2 feet. To the extent practical, clean sand backfill was placed over the geotextile during the shift in which the geotextile was placed. Conventional and amphibious excavation equipment and hand shovels were used to perform the backfill. Thickness was verified during placement by probing the backfill using a steel reinforcing bar marked at the prescribed 18-inch depth. 15 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Excavated sediment was staged in an earthen bermed, temporary holding area on the shore immediately north of the creek. Kiln dust was immediately added to the excavated sediment in the holding area to solidify the sediment. The solidified sediment was then placed in approximate 500-cubic-yard (CY) stockpiles for use onsite during the soil remedy. Because the kiln dust soaked up the water in the sediment, water was not discharged from the holding area and water quality sampling was not necessary.

During sediment removal and sand cap placement, a portion (less than 1 acre) of the adjacent tidal marsh was disturbed. The disturbed area was returned to approximate original grade at the completion of remediation activities in January 2005. As required by the Critical Area Permit, a Marsh Restoration Plan (ENTACT, January 2005) was then submitted to OCRM in January 2005. Upon OCRM approval of the plan on February 14, 2005, marsh restoration was performed March 11 through March 13, 2005. Restoration activities included planting 5,900 1-gallon Spartina alterniflora on 3-foot centers (approximately 120 plants per 1,000 square feet). In addition, 196 feet of shoreline were restored by planting 40 5-gallon Baccharis halimifolia on 5-foot centers.

4.2.3 O&M O&M required by the FRAR for Zone A consisted of 001 Tidal Creek Cap thickness measurements and survival and stem density surveys of the hand-planted grass.

4.2.3.1 001 Tidal Creek Cap Monitoring Thickness Measurements Yearly measurement events of the tidal creek cap thickness were required by the FRAR after construction was completed. EnSafe conducted measurement events as outlined by the FRAR in June 2006, June 2007, June 2008, and June 2009. Measurements were attained by inserting a rod into the sand cap to determine the depth of clean sand above the geotextile at 100-foot intervals along the centerline of the creek. Any thickness less than 18 inches was evaluated for severity of sand loss and the need for repair. Measurement transects on a site-wide map are shown in Figure 4-2.

A five-year review of this data is provided in Section 6.

16 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Maintenance and Repair From 2006 to 2008, yearly tidal creek cap thickness reports indicated that exposed geotextile fabric was observed near Transect 3 (Ensafe 2008). Approximately 16 linear feet of fabric was pulled away from the sides of the creek and out from under the 18 inch sand cap.

The Macalloy PRP Group contracted ENTACT to repair the cap and EnSafe to document and report field activities. Field activities were conducted on December 22, 2008, and in accordance to the Technical Memorandum 001 Tidal Creek- Work Plan to Repair Cap near Transect 3 (EnSafe, December 1, 2008).

Sediment beneath the exposed liner was removed with shovels to approximately 18 inches bgs. Excavated sediment was temporarily staged adjacent to the repair area to allow for reuse of the material. The existing geotextile liner was not damaged and therefore, was replaced across the excavated area and secured. The staged sediment was then replaced over the geotextile liner and graded to the natural contours of the creek bed. Stability of the repair will be observed in future thickness surveys. On February 9, 2009, EnSafe submitted the 001 Tidal Creek Cap Repair Completion Report Technical Memorandum (EnSafe, 2009) to the EPA and SCDHEC documenting all completed work activities.

4.2.3.2 Tidal Marsh Plant Surveys O&M required by the FRAR and OCRM consisted of a survival rate survey during the first year and stem density surveys in the second and third years. Success criteria for the restored tidal marsh was determined to be greater than 70% survival rate and stem density when comparing the hand-planted 5. alterniflora in the restored tidal marsh to the undisturbed plants in the adjacent marsh. The location of the restored tidal marsh is shown in Figure 4-1 and Figure 4-2.

Hutton Landscapes conducted the survival rate survey in 2006 and EnSafe conducted the stem density surveys in 2007 and 2008.

A five-year review of this data is provided in Section 6.

17 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

4.2A Five-Year Costs

Table 4-1 Zone A O&M Costs during the Five-Year Review Period

Cost Item Estimated Cost Actual Cost

Tidal Creek Cap Thickness Measurements $10,500 $10,500

Tidal Marsh Plant Surveys $10,800 $10,800 $2,700 (EnSafe) + Repair of Cap Not Estimated $3,500 (Entact)

4.3 Zone C Sediment The ERA indicated that one measurement endpoint, embryo production, in the middle portion of Zone C in Shipyard Creek exhibited unacceptable risks to benthic organisms.

4.3.1 Remedy Selection Based on the strength and magnitude of observed adverse effects and the expectation of diminishing risks following site remediation, a risk management decision was made by EPA and the Natural Resource Trustees to only monitor Zone C sediment.

4.3.2 O&M O&M required by the FRAR during the five-year review period consisted of three sediment monitoring events in the middle portion of Zone C. The first was required immediately after completion of the storm water management plan, the second in two years and the third during the five-year review.

As outlined by the FRAR, sediment monitoring events were conducted by EnSafe in October 2006, September 2008, and October 2009. Five discrete sediment samples were collected from 0 to 6 inches below grade using a Ponar grab sampler at the locations shown in Figure 4-3. Samples were shipped to and analyzed by TestAmerica in Savannah, Georgia, for the following parameters: total chromium, nickel, zinc with EPA Method 6010B; percent moisture with EPA Moisture methods; grain size (percent sand, silt, clay) with ASTM D422; and total organic carbon with EPA Method 9060. A composite of the five discrete sediment samples was analyzed for total chromium, nickel, zinc, and percent moisture with the methods listed above.

18 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

In October 2009, the five discrete samples described above and a background sample from Rathall Creek (Figure 4-4) was analyzed for toxicity by TRAC laboratories in Pensacola, Florida. Toxicity tests were chronic 7-day, whole sediment, with the single measurement endpoint of embryo production (survival and reproductive development) using the Americamysis bahia {Mysidopsis bahiaj grass shrimp following EPA standard procedures.

Analytical data was compared to the following protective risk ranges established for Zone C sediment:

• total chromium: 219 to 258 milligrams per kilograms (mg/kg) • nickel: 33 to 35.7 mg/kg

• zinc: 132 to 163 mg/kg

A five-year review of this data is provided in Section 6.

4.3.3 Five-Year Costs Table 4-2 Zone C Sediment Monitoring Costs during the Five-Year Review Period

Cost Item Estimated Cost Actual Cost

Sediment Monitoring $33,000 $33,000

4.4 Groundwater: Enhanced In Situ Chemical Reduction During the RI, five hexavalent chromium plumes were delineated in the shallow groundwater. Four of these plumes (Plumes I through IV) extended from the former LFA toward Shipyard Creek; a fifth (Plume V) was in the former concentrator area.

4.4.1 Remedy Selection The following RAO were specified in the ROD for the groundwater.

• Prevent future site worker exposure to unacceptable hazard levels in groundwater.

• Remediate shallow groundwater zones with the highest concentrations of hexavalent chromium to minimize long-term threats and limit hexavalent chromium migration into Shipyard Creek.

19 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

The ROD documented the selection of enhanced in situ reduction using chemical reductants. The objective of the groundwater remedy is to prevent exposure to hexavalent chromium in shallow groundwater above the Safe Drinking Water Act MCL of 100 micrograms per liter (pg/L) and to minimize hexavalent chromium migration from groundwater to Shipyard Creek. The remedy also includes a deed restriction regarding use of groundwater.

4.4.2 Remedy Implementation (2004-2005) EPA performed an in situ chemical reduction pilot study in three phases between mid-2001 and January 2003 to examine the feasibility of treating hexavalent chromium in groundwater using soluble reductants and to establish design criteria for full-scale implementation. EPA's pilot study recommended installation of reduction/oxidation (redox) zones in the form of permeable reactive barriers (PRBs) to treat groundwater downgradient of source areas. This approach was recommended over a plume-wide injection strategy due to technical and cost concerns. The study concluded that long-term redox zones could be created by injection of a ferrous sulfate and sodium dithionite solution into short-term wells screened across the shallow aquifer. The study found that an injection radius of influence of 7.5 feet could be achieved at an injection rate of 10 to 15 gallons per minute and an injection pressure of 10 pounds per square inch (psi). The EPA pilot study formed the basis for final design and implementation of groundwater remediation.

Following additional delineation and lithologic investigations in December 2003 the groundwater injection strategy was optimized in June 2004. In general, this involved reorientation of redox barriers, and modification of the chemical reductant. A ratio of 0.1 Molar (M) ferrous sulfate to 0.1 M sodium dithionite was injected into the aquifer where there was not enough naturally occurring iron in the saturated zone to facilitate treatment. Transects that had sufficient naturally occurring iron in the aquifer received a combination of 0.1 sodium dithionite along with 0.4 M potassium carbonate buffer to raise the pH, encourage precipitation of ferrous carbonate (siderite) and improve sorption of ferrous iron.

Injection well installation began in October 2004 and was completed in November 2004. Chemical injection began November 14, 2004, and was completed March 5, 2005. Sodium dithionite buffered with potassium carbonate was injected into 119 wells in Transects 2, 5, 6, and 7. The sodium dithionite/ferrous sulfate solution was injected into 84 wells in Transects 1, 3, 4, and 8. The location of injection wells are shown on Figure 4-1.

20 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Both reductants were diluted onsite with municipal water in clean holding tanks designed to minimize aeration and were then injected into the subsurface. The potassium carbonate buffer was blended onsite with the sodium dithionite immediately prior to injection. The system was designed to regulate the injection flow rate and pressure through a manifold designed to inject up to five wells at the same time. The reductant volumes used to complete the redox barrier zones are summarized below:

Diluted Solution Full-Strength Solution Number of Chemical Reductant (Gallons) (Gallons) Injection Wells Sodium dithionite + potassium carbonate 300,917 37,150 119 Sodium dithionite -t-ferrous sulfate 182,352 72^941 84 TOTAL 483,269 110,091 203

During implementation it was not possible to effectively inject chemical reductants at the designed quantities into a number of wells in Plumes I, II, III, IV and most of the wells in Plume V. These quantities were not possible due to breakthrough around the well seal or at the ground surface caused by subsurface obstructions, variability, or low permeability aquifer matrix materials. Of the 203 injection wells, 115 successfully accepted 70% or more of the design volume. The remaining locations were evaluated for alternative injection mechanisms.

Because of the difficulties encountered with injecting chemicals into conventional wells at a number of locations, redox barriers and/or PRBs in the form of in situ trenches were evaluated in a pilot test trench. This alternative did not require a change in the fundamental design of chemical reductive barriers or the type of reductants; rather, the delivery mechanism was modified to overcome injection difficulties.

Based on positive results from the pilot test, full-scale trench installation was conducted from December 2 to December 20, 2005. In all, approximately 625 feet of trench was installed. The trenches were created by first excavating and staging vadose zone soil. Aquifer matrix material in the saturated zone and the chemical reductants were mixed in cells using a trackhoe to distribute the chemicals to a depth of 20 feet bgs and across the entire vertical and horizontal extents of the barrier. The dry forms of the chemicals were applied in the same molar ratios as those used for the injection wells.

21 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

For each 50 linear feet of trench, approximately 3,000 pounds (lbs) of ferrous sulfate, 3,500 lbs of sodium hydrosulfite, and 30 CY of #789 crushed (gravel) were used. The addition of gravel facilitated hydraulic interaction and maintained groundwater gradient balance. The trenches were then capped with the vadose zone material removed during trench construction and returned to original grade.

4.4.3 Supplemental Remedy Implementation (2008) Installation of MW060. MW061. MW062 During the five monitoring events from October 2006 to October 2007 (Events 1 through 5), two long term effectiveness groundwater monitoring wells (MW041 and MW047) showed persistent concentrations of total chromium above the cleanup goal (100 pg/L). Total chromium was used as a conservative surrogate measurement for hexavalent chromium in post-treatment samples, due to the matrix interferences with the hexavalent chromium method caused by the chemical reductants in the PRBs. An "X" laboratory data qualifier was used to indicate a hexavalent chromium result had matrix interference. Figure 4-2 presents a map of monitoring well locations and Section 6.4 provides a comprehensive review of the analytical results during the five-year review period. In November 2007 SCDHEC requested the installation and sampling of three new monitoring wells to assess the northern and southern extent of chromium and arsenic in the vicinity of MW041 and MW047. Further, SCDHEC requested a supplemental groundwater treatment to address the areas of residual total chromium above the cleanup goal.

In February 2008, monitoring wells (MW060, MW061, and MW062) were installed and sampled to the north, west, and south of MW041 and MW047. Two subsequent monitoring events (Events 5A and 6) showed elevated total chromium concentrations above the cleanup goal at MW060 and MW061, and low concentrations below the cleanup goal at MW062. Based on this data, a residual chromium plume was identified from MW047 to MW060, with each direction delineated with exception of the northern extent. No monitoring wells were located north of MW060.

Field procedures and results from the installation and sampling of these three new wells are provided in the Long Term Groundwater Monitoring Report for Event 5A (EnSafe, March 4, 2008).

DPT Assessment (Event 6A) To delineate the chromium plume to the north of MW060, a direct push technology (DPT) assessment was conducted in the vicinity. In July 2008 eight, one-inch diameter temporary wells were installed; groundwater was sampled and analyzed for hexavalent and total chromium. Hexavalent and total chromium results from the filtered and unfiltered samples were less

22 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010 than 19 pg/L and below the cleanup goal (100 pg/L). The DPT assessment indicated that the plume was confined to the north by temporary well TW08 and to the northwest by TWOl, TW02, TW03, and TW04. Sample locations are shown on Figure 4-2. Field procedures and results from the DPT assessment were provided to the EPA in the Results of Potential Plume Delineation in the Vicinity of MW060 Technical Memo (Event 6A) {Ensafe, August 19, 2008).

Additionally, groundwater samples collected from MW060, MW061, and MW062 indicated that total chromium concentrations above the cleanup goal were isolated to the vicinity of MW041, MW047, MW060, and MW061.

Supplemental Groundwater Treatment To address sustained total chromium concentrations above the cleanup goal in the vicinity of MW041, MW047, MW060, and MW061, the EPA and SCDHEC requested a supplemental groundwater treatment similar to the PRBs constructed in 2005.

Additional PRBs were installed by ENTACT and EnSafe from December 19 to December 21, 2008. A summary of the PRB installation is provided below and is presented in the Supplemental Groundwater Treatment Completion Report {EnSafe, February 9, 2009).

Supplemental groundwater treatment near monitoring wells MW041, MW047, MW060, and MW061 consisted of the installation of redox zones in the form of PRBs using trenching methods and components similar to those constructed at the Site in 2005 and described in the FRAR. One PRB was installed approximately 25 feet upgradient of each of the aforementioned monitoring wells, intersecting groundwater flow, for a total of four PRBs and 350 linear feet.

Before construction. South Carolina Underground Injection Control Permit #577M4 was attained and the PRB design locations were surveyed by Thomas & Hutton, a South Carolina licensed surveyor. The table below presents a summary of the supplemental PRB dimensions and components. A map of PRB locations is shown in Figure 4-1.

23 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Table 4-3 Supplemental PRB Dimensions and Components | Ferrous Sodium PRB Length Depth Approximate sulfate Hydrosulfate #789 Gravel Location (ft) (ft bgs) Width (ft) (lbs) (lbs) (cubic yard) MW041 100 18 4 6000 7000 60 MW047 100 18 4 6000 7000 60 MW060 100 18 4 6000 7000 60 MW061 50 18 4 3000 3500 30 TOTALS 350 - - 21000 24500 210

Note^. PRB Permeable reactive barriers ft Feet lbs Pounds

4.4.4 O&M O&M required by the FRAR consisted of long term groundwater monitoring to assess the soil and groundwater remedy treatment effectiveness. The monitoring program outlined in the FRAR was optimized several times during the first five year period and is summarized below. Sample collection, shipment, and analysis conducted by EnSafe, and TestAmerica in Savannah, Georgia, were in accordance to EPA protocols; FRAR and the Macalloy Quality Assurance Project Plan (QAPP) (EnSafe, May 15, 2000). Groundwater analytical results were compared to the total and hexavalent chromium cleanup goal of 100 pg/L. Figure 4-2 presents a map of groundwater sampling wells discussed in this section. A chronology of monitoring and supplemental remedial action for the site groundwater is presented in Table 4-4.

Table 4-4 Chronology of Post-Construction Groundwater Events Date Reference Name Purpose December 2004 Remedial Construction Began December 2005 PRBs Complete May 2005- April 2006 Short term Short-Term Effectiveness Monitoring, Quarterly October 2006 LTM Event 1 Long-Term Effectiveness, Year 2 Quarter 1 January 2007 LTM Event 2 Long-Term Effectiveness, Year 2 Quarter 2 April 2007 LTM Event 3 Long-Term Effectiveness, Year 2 Quarter 3 July 2007 LTM Event 4 Long-Term Effectiveness, Year 2 Quarter 4 October 2007 LTM Event 5 Long-Term Effectiveness, Year 3 Semi-annual 1

24 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Table 4-4 Chronology of Post-Construction Groundwater Events Date Reference Name Purpose Installed and sampled new permanent wells (MW60, MW61, February 2008 LTM Event 5A MW62) to assess elevated chromium levels April 2008 LTM Event 6 Long-Term Effectiveness, Year 3 Semi-annual 2 July 2008 Event 6A Delineated chromium in the vicinity of MW060 with DPT. October 2008 LTM Event 7 Long-Term Effectiveness, Year 4 Semi-annual 1 December 2008 Supplemental Groundwater Treatment (PRBs) Complete April 2009 LTM Event 8 Long-Term Effectiveness, Year 4 Semi-annual 2 October 2009 LTM Event 9 Long-Term Effectiveness, Year 5 Semi-annual 1

October 2006 — October 2007 From October 2006 to October 2007 (Events 1 through 5), groundwater monitoring was conducted as scheduled in the FRAR to assess the long term effectiveness of remedial action. Twenty permanent groundwater wells were sampled quarterly the first year and annually thereafter. Groundwater samples were analyzed for hexavalent chromium with EPA Method 7196A and the metals arsenic, barium, cadmium, total chromium, lead, mercury, selenium, and silver using EPA Contract Laboratory Program methods. Wells in the monitoring network included MW040 through MW059.

April 2008 - April 2009 In January 2008, SCDHEC and EPA approved an optimization of the monitoring program to reduce the number of wells in the network, reduce the analytical parameters to only include total chromium, hexavalent chromium, and arsenic, and increase the sample frequency from annual to semi-annual {Optimized Remedial Groundwater Program Technical Memorandum, [EnSafe, January 8, 2008]). The list was optimized to remove parameters that were no longer detected above the MCL. Additionally, monitoring wells MW060, MW061, MW062 were installed in February 2008, as described in the previous section, and added to the sampling network. During this time period, eighteen total wells were included in the monitoring network: MW040 to MW052, MW054, MW059, MW60, MW061, and MW062.

In the summer of 2008, new buildings were constructed onsite and wells MW054 and MW057 were abandoned, moved away from the building foundation, and replaced by the installation of wells MW054R and MW057R. Additionally, MW056 and MW058 were modified from above ground casings to flush mount construction.

25 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

October 2009 During the Five-Year Review site inspection on October 16, 2009, EPA and SCDHEC further optimized the monitoring program. Monitoring wells MW049, MW050, MW051, and MW059 were removed from the program and wells MW055, MW056, and MW057R were added to the sampling network due to an exceedance observed in MW054R during Event 8. MW054R could not be located and sampled during Event 9; therefore, MW058 was sampled as a temporary replacement. MW054R is located in a facility road with heavy truck traffic and was covered by compacted gravel and road fill. No survey coordinates are available for MW054R; therefore, EnSafe attempted to find the well with a standard grade metal detector with no success. Further, due to the heavy compaction, plant personnel were not successful in their attempts to remove a layer of fill with their front-end loader to assist in finding the well. MW056 could also not be sampled during Event 6; the location of this well has become a storage area for recyclable material staged for disposal by the facility. Plant management could not inform EnSafe of a date when the staged plastic would be moved. MW058, not originally included in the monitoring network, was sampled as a substitute for MW056.

A five-year review of this data is provided in Section 6.

4.4.5 Five-Year Costs

Table 4-5 Groundwater Monitoring and Remedial Costs during the First Five-Year Review Period

Cost Item Estimated Cost Actual Cost Groundwater Monitoring $122,900 $129,200 Installation and sampling of MW060, Not Estimated $16,770 MW061 and MW062 (Event 5A)

DPT Assessment (Event 6A) Not Estimated $15,000

Supplemental Groundwater Treatment $20,300 (EnSafe) -i- Planning, Implementation, and Completion Not Estimated $116,690 (Entact) Report

4.5 Soil: Onsite Chemical Reduction During the RI, concentrations of hexavalent chromium in soil at the LFA, former casting bay/furnace buildings, the former concentrator area, and other isolated locations across the Site, indicated a significant potential for migration from soil to groundwater.

26 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

4.5.1 Remedy Selection The following RAO was specified in the ROD for the soil.

• Remediate soil that leaches hexavalent chromium to groundwater and surface water at concentrations hazardous to human health and the environment.

The ROD documented the selection of chemical reduction using mechanical mixing to convert hexavalent chromium to the less mobile (and less toxic) trivalent form, chromium (III). Bench- and pilot-scale treatability studies were conducted during the RD to evaluate chemical reductants and mixing methods. The objective of the selected soil remedy was to prevent the leaching of hexavalent chromium from site soil to groundwater at concentrations exceeding the groundwater cleanup goal of 100 pg/L.

4.5.2 Remedy Implementation Prior to construction activities, a Soil Specific Remedial Action Work Plan (ENTACT, 2004) was prepared and submitted to EPA and SCDHEC. The work plan addressed chemical reductant selection, soil mixing approach, erosion prevention and sediment controls, site demolition and debris disposal, wastewater management, and site restoration.

Site demolition began shortly after the October 2004 mobilization and included the dismantlement, decontamination, and offsite disposal or recycling of all facility buildings, foundations, former groundwater treatment system components, monitoring wells, concrete pads, rail track, utilities, miscellaneous piping, aboveground storage tanks, underground storage tanks, and miscellaneous debris.

Full-scale soil treatment in the primary soil remediation areas began on March 22, 2005, and was completed on October 13, 2005. Figure 4-1 shows the boundaries of soil excavation and treatment. Over 160,000 CY of soil was treated in these areas. In general, soil treatment consisted of excavating contaminated soil and mixing with the reductant until the cleanup goal was attained. The soil cleanup goal for hexavalent chromium-impacted soil above the water table was 23 mg/kg. This value was a site-specific concentration calculated during the RI to minimize leaching of hexavalent chromium from soil to groundwater at concentrations above the drinking water MCL of 100 pg/L. The cleanup goal for soil below the water table was a synthetic precipitation leaching procedure (SPLP) concentration of 100 pg/L. Depending on the percent solids of the material, a SPLP concentration of 100 pg/L is approximately equal to hexavalent chromium concentrations in soil ranging from about 2 to 4 mg/kg.

27 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

The water-table elevation was estimated to be 5 feet below final grade. Based on this estimate, only soil with hexavalent chromium SPLP concentrations less than or equal to 100 pg/L could be placed at depths greater than 5 feet bgs. Soil with SPLP concentrations greater than 100 pg/L, but with total hexavalent chromium concentrations less than 23 mg/kg, could be placed within the top 5 feet.

The following details the key activities conducted during soil treatment:

• Site material that had been stockpiled above original site grade in the LFA was excavated and placed in approximate 500-CY stockpiles for treatment. Each stockpile was assigned a unique identifier and marked in the field with labeled pin flags. Stockpiling began on January 17, 2005.

• A full-scale soil treatment demonstration was conducted from February 1 through 12, 2005. Approximately 1,000 CY of above grade material and 1,000 CY of below grade material were mixed with 1% calcium sulfide powder by weight using a pug mill or a tracked excavator.

• The initial demonstration proved unsuccessful and a second demonstration was completed from March 3 through March 21, 2005, using liquid calcium polysulfide (CaS4). Each stockpile was mixed with CaS4 at application rates ranging from 2% to 5% by weight using a pug mill or a tracked excavator.

• Based on the results of the demonstration, full-scale soil treatment of above-grade stockpiles using 3% CaS4 by weight was initiated on March 22, 2005. Mixing was accomplished primarily with a tracked excavator. Above-grade material was excavated to the approximate grade of surrounding areas.

• Treated stockpiles were sampled and analyzed in the field laboratory using HACH test kits for hexavalent chromium. Initially, all treated stockpile samples were also submitted to a laboratory for comparison with results from the field laboratory. After comparing test results on 19 treated stockpile samples, the field laboratory results were deemed adequate for treatment verification and, on March 29, 2005, submission of samples to the laboratory was reduced to 10% as a quality control measure.

28 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

The 500-CY stockpiles that met cleanup goals were consolidated into two larger stockpiles based on hexavalent chromium concentrations. Material with SPLP concentrations less than 100 pg/L was acceptable for placement below 5 feet bgs and was consolidated into one stockpile. Material with SPLP concentrations greater than 100 pg/L, but with total concentrations less than 23 mg/kg, was acceptable for placement in the top 5 feet and was consolidated into a second stockpile. Stockpiles that did not meet cleanup goals were retreated and resampled until the goals were met.

Below-grade excavation and treatment was initiated in the Casting Bay/Furnace Area on March 30, 2005. Due to the presence of extensive concrete slabs and foundations (many of which required removal), excavation in the area continued periodically and was completed in September 2005.

Below-grade excavation and treatment was initiated on the west side of the LFA on May 10, 2005. Below-grade material was stockpiled in 500-CY piles and treated with 3% CaS4 by weight. Excavations were completed in 25-foot-square grids to the bottom design elevations. A laser level and survey rod was used to verify that excavation depths were achieved.

Upon achieving design excavation depths, below-grade excavations were backfilled to preexcavation grades using treated stockpile material suitable for placement below the water table.

Excavation and ex situ treatment continued with excavations generally proceeding from north to south working from the west side of the remediation area to the east side.

Hexavalent chromium-impacted groundwater encountered during excavation was treated with CaS4 prior to backfilling. Excess water was "pushed" ahead of the backfill until the water approached the existing ground surface elevation. Then, the water was either allowed to infiltrate and/or was pumped into a temporary holding pond within the remediation area. Water in the excavations and in the holding pond was periodically sampled for hexavalent chromium concentrations to ensure that adequate reductant had been added and that hexavalent chromium concentrations were less than 100 pg/L.

29 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

• Upon completion of soil treatment in October 2005, soil strength enhancement activities were initiated in the LFA. Strength enhancement activities included reworking the upper 2 to 3 feet of treated soil using bulldozers, tracked excavators, and a sheepsfoot compactor. Areas of soft wet soil were excavated or wind-rowed to a depth of 2 to 3 feet, allowed to air dry, and recompacted.

• Verification that adequate soil strength had been achieved was conducted by S&ME of Mount Pleasant, South Carolina, using cone penetration testing. Areas that did not meet strength requirements were mixed with Portland cement and retested. Soil strength enhancement was completed in July 2006.

Soil excavation also occurred at isolated "hot spots" across the Site at depths ranging from 1 to 7 feet bgs and as identified during the RI. Excavated soil from areas outside the soil remediation area was transported to the soil remediation area and stockpiled for treatment and placement. Samples of treated hot spot stockpiles were collected and analyzed for hexavalent chromium in the field laboratory. Ten percent of samples were sent to a laboratory for verification. Approximately 5,000 CY of soil was effectively treated from the "hot spot" areas onsite.

In December 2005, during Site grading activities immediately east of the former concentrator area, ENTACT encountered a layer of dense white material suspected to- be low carbon slag and furnace rubble from the earliest days of the ferrochromium plant's operation. The material ranged from about 2 feet to 7 feet in thickness and ranged from 1 to 4 feet below existing grades. Initial hexavalent chromium analysis of the material conducted in the field laboratory indicated most of the material to be below the cleanup goal of 23 mg/kg. The low carbon slag/furnace rubble was excavated, placed in approximate 500-CY stockpiles, and sampled. Although only two piles had concentrations greater than the cleanup goal, all piles were treated with 3% CaS4 and placed within the soil remediation area. Approximately 22,500 CY of low carbon slag/furnace rubble was treated and backfilled onsite.

Performance standards and construction Quality Assurance/Quality Control requirements for the soil remedy were detailed in the Pre- and Post Construction Sampling and Analysis Plan and the Construction Quality Assurance Plan (EnSafe, September 4, 2003) in the Final Design for the Macalloy Corporation Site, Charleston, South Carolina. Specific performance standards included verification that soil remediation areas were treated to meet the cleanup goal and placed within the designated limits.

30 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

To improve soil geotechnical properties for potential future redevelopment of the Site, the Final Design included stabilization of soil with agents such as Portland cement to achieve unconfined compressive strengths of 50 pounds per square inch in the top foot and 15 pounds per square inch from 1 to 5 feet bgs. After the property was purchased by Ashley II, the strength requirements were modified to support the new redevelopment plans for the Site. The new strength requirements primarily consisted of a cone tip pressure of 25 tons per square foot for the top 5 feet of soil based on cone penetration testing. The new Ashley II requirements also called for a 6-inch layer of clean fill to be placed over treated soil to minimize erosion.

4.5.3 O&M O&M was not required for the soil remedy. Groundwater monitoring as described in the previous section was required to assess long term effectiveness of the soil and groundwater remedy.

4.6 Surface and Storm Water: Comprehensive Storm Water Management Surface water discharge samples indicated hexavalent chromium exceeded NPDES limits. Additionally, arsenic, copper, lead, and zinc were identified as constituents of concern because of concentrations measured in surface water discharge to Shipyard Creek.

4.6.1 Remedy Selection The following RAO were specified in the ROD for the storm water.

• Mitigate offsite hexavalent chromium discharges in storm water to Shipyard Creek through soil and groundwater remediation measures and a comprehensive site-wide storm water management plan.

• Manage storm water discharges of toxic inorganic compounds in accordance with the comprehensive storm water management plan to protect ambient saltwater quality in Shipyard Creek.

4.6.2 Remedy Implementation The storm water remedy selected in the ROD focused on mitigating pollutant discharge into Shipyard Creek by constructing a comprehensive storm water management system that meets the requirements of the South Carolina Storm Water Management and Sediment Reduction Act of 1991, as administered by OCRM. The selected storm water remedy, in conjunction with the selected soil and groundwater remedies, was developed to meet the hexavalent chromium cleanup goals in storm water discharges from the Site to 31 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Shipyard Creek, and to control sediment (total suspended solids) concentrations in discharge water, thereby reducing arsenic, copper, lead, zinc, and other metals.

Key remedial performance standards for the storm water management system established in the ROD are summarized below:

• Design storm water detention basins and other conveyances to reduce suspended sediment concentrations and handle peak flows from the 10-year, 24-hour storm event.

• Relocate and consolidate storm water outfalls into one discharge.

• Regrade Site topography and construct ponds, berms, and swales to accommodate storm water for future site use.

A comprehensive storm water management plan, presented in the Final Design, was prepared to meet the ROD performance criteria. In February 2005, the Site was purchased by Ashley II, who later contracted General Engineering and Environmental LLC of Charleston to redesign the storm water management system to accommodate future Site development and the ROD performance criteria. The redesigned plan was approved by EPA and OCRM on September 9, 2005 and October 13, 2005, respectively. The redesigned storm water plan included the following additional components:

• No storm water from offsite watersheds.

• Underground pipe sections were sealed with rubber gasket joints to minimize the potential for groundwater infiltration.

• Design elements (migration barriers) were added to minimize preferential groundwater flow along underground pipes and into ditches and ponds.

Construction of the storm water management system was considered complete upon signing of the PCOR in September 2006. ENTACT was the primary construction contractor and EnSafe performed daily inspections to verify that ROD-established performance criteria were satisfied. A map of the completed storm water management system is provided in Figure 4-5.

32 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

4.6.3 O&M The property owner is responsible for the routine operation and maintenance of the storm water system to ensure its efficiency. This includes periodic inspection of the storm water pipe, manholes, drainage grates, ditches, and detention basins to ensure storm water flow is unobstructed. If necessary, obstructions will be removed to resume normal operation. Sediment accumulation must also be monitored during the inspections. Sediment should be mechanically removed if the conveyance system effectiveness is impacted.

Additionally, monthly onsite storm water monitoring was required by the FRAR for one year following completion of construction. Onsite storm water monitoring was conducted monthly by Magnolia Development, LLC, an Ashley II partner, from August 2006 to June 2008. An automatic sampler collected a grab sample within the first 30 minutes of an initial discharge that resulted from a rainfall event exceeding 0.5 inches in magnitude. If no event occurred, no samples were collected for that month. Storm water monitoring results were reported monthly to EPA and SCDHEC by the 20th day of the month after collection. Offsite storm water contributions were eliminated from the redesigned system; therefore no offsite storm water samples were required. Specific performance and monitoring criteria for the storm water outfall were detailed in the January 20, 2005, Storm Water Discharge Limitations, Macalloy Corporation Site Memorandum (EnSafe, January 2005) to the EPA. On July 16, 2008, Magnolia Development, LLC, received notification from SCDHEC that storm water monitoring could be terminated because monthly monitoring data had consistently met the performance criteria established by the department (Appendix A).

4.6.4 Five-Year Costs

Table 4-6 Storm Water Monitoring Costs during the Five-Year Review Period Cost Item Estimated Cost Actual Cost Storm water Monitoring $17,000 $25,140

4.7 Institutional Controls As a part of the site-wide remedy, institutional controls and restrictive covenants were executed for the Site that limit future use to commercial/industrial purposes, and prohibit the use of groundwater underlying the property. These institutional controls were approved by the EPA and SCDHEC in May 2006 and have been officially recorded with the Charleston Register of Mesne Conveyance Office. A copy of the restrictive covenant is provided in Appendix B. Current and future land use for the Site is industrial and commercial use only. 33 i N)):-

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First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

5.0 Progress since the Last Review This report documents the first five-year review for the Site.

34 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

6.0 Five-Year Review Process The Five-Year Review process for this Site included a review of technical documents, long term monitoring reports, technical meetings with key project personnel, and a formal site inspection.

6.1 Administrative Components EPA notified The Macalloy PRP Group of the start of the Five-Year Review process via a telephone call on August 28, 2009. EnSafe was asked to prepare the 2009 First Five-Year Review for the EPA.

The review team is shown below:

Craig Zeller, Remedial Project Manager, EPA Tim Nelson, Project Coordinator, Macalloy PRP Group Charles Williams, Project Manager, SCDHEC Chad Tripp, Project Manager, EnSafe Frank Mclnturff, Senior Project Engineer, EnSafe Brian Mulhearn, Senior Project Scientist, EnSafe Sherryl A. Carbonaro, Public Affairs Specialist, EPA Tonya James, Community Involvement Coordinator, EPA

6.2 Community Notification & Involvement The EPA notified the community of the Five-Year Review through a VA page advertisement (Appendix C) posted in Charleston's daily newspaper. The Post and Courier, on November 18, 2009 and by conducting interviews of individuals in the community surrounding the Site on November 30, 2009. Sherryl Carbonaro (Public Affairs Specialist, EPA) and Tonya James (Community Involvement Coordinator, EPA) visited 24 homes in the community and interviewed 10 individuals. A copy of the newspaper advertisement was left at each home visited. None of the interviewed residents expressed concerns over the Site, or the protectiveness of its remedy. To date, no residents have contacted the EPA concerning the Macalloy Site.

Once the First Five-Year Review is completed, the EPA will publish another advertisement in The Post and Coiyr/er indicating the completion of the review. Copies of the First Five-Year Review will be placed in the EPA and local repository for public access.

35 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

6.3 Document Review The list of documents reviewed as part of the development of this Five-Year Review Report is included in Appendix D. RAOs, applicable or relevant and appropriate requirements and cleanup goals were defined by the ROD.

6.4 Data Review The following sections review data collected during groundwater monitoring events, 001 Tidal Creek cap thickness measurements, tidal marsh plant surveys, and Zone C sediment monitoring during the five-year review period.

6.4.1 Review of Groundwater Monitoring Data Data from nine long term groundwater monitoring events (Event 1 to Event 9) from October 2006 to October 2009 are reviewed in this section. A summary of this data is presented in Table 6-1 and Figure 6-1.

Chromium Comprehensive groundwater results through Event 9 indicate that the total chromium cleanup goal of 100 pg/L has been achieved at 19 of the 23 long term monitoring wells: MW040, MW042, MW043, MW044, MW045, MW046, MW048, MW049, MW050, MW051, MW052, MW053, MW055, MW056, MW057/ MW057R, MW058, MW059, MW061, and MW062.

Total chromium concentrations were reported above the cleanup goal during Event 9 and prior events at monitoring wells MW041, MW047, and MW060. Linear graphs depicting total chromium reduction over time are included on Figure 6-1. Overall reducing trends can be observed at wells MW041, MW047, and MW060, with the most reductions occurring between Events 7 and 8. Accelerated reduction after Event 7 is likely a result of the December 2008 construction of supplemental PRBs immediately upgradient of these wells. The supplemental PRBs should continue to promote reduction of total chromium during future monitoring at these wells.

Monitoring well MW054 was abandoned in the summer of 2008 and reinstalled (MW054R) approximately 50 feet to the west. Prior to the reinstallation, total chromium had not been reported above the cleanup goal during monitoring events at this well; however after reinstallation, results measured during Event 8 (3900 pg/L) reported total chromium above the cleanup goal. Monitoring well MW054R was not able to be located during Event 9; therefore, groundwater samples were not collected.

36 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Arsenic Arsenic concentrations were reported below the MCL of 10 pg/L for all monitoring events performed at 13 of the 23 long term monitoring wells.

Arsenic concentrations were reported above the MCL during Event 9 and previous monitoring events at wells MW041, MW043, MW044, MW047, MW045, MW053, MW054, MW058, MW060, and MW061. The FRAR showed that concentrations of some heavy metals, including arsenic, temporarily increased after PRB installation and would decrease with time. Wells with sustained elevated arsenic concentrations are located in the PRB zone where low oxidation reduction potential conditions are prevalent and are expected to decrease with time.

Barium. Cadmium. Lead. Mercury. Selenium, and Silver Groundwater results from Events 1 to 5 indicated concentrations of barium, cadmium, lead, mercury, selenium, and silver were less than laboratory reporting limits at long term monitoring wells; therefore, these parameters were removed from the long term monitoring analytical list during the 2008 program optimization.

Groundwater Elevations Data to determine site-wide shallow aquifer groundwater elevation contours and flow direction was collected during each monitoring event performed over the five-year review period. Groundwater elevations were referenced to mean sea level National Geodetic Vertical Datum of 1929. Figure 6-2 presents a map of groundwater elevations, contours, and flow direction during Event 9. Groundwater flow is generally north and northeast towards Shipyard Creek and is consistent with the flow direction during all monitoring long term monitoring events. Top of casing elevations for flush-mount wells MW054R, MW056, MW057R, and MW058 are not surveyed; therefore, groundwater elevations were estimated during Event 9 based on surveyed topography. These wells were reinstalled or had their casings reduced during building construction, and subsequently removed from the monitoring program. Prior to Event 9, they were reintroduced to the monitoring program.

Recommendations for Future Monitoring During the October 2009 First Five-Year Site Inspection and subsequent email communication, SCDHEC and EPA recommended groundwater monitoring to continue semi-annually for the next two years and then annually for the following three years until the second five-year review. Monitoring wells MW049, MW050, MW051, MW052 and MW059 have consistently demonstrated concentrations of chromium below the established cleanup goal; therefore they are recommended

37 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010 to be dropped from the long-term monitoring network, but not abandoned at this time in case additional samples are required in the future. The following 16 monitoring wells will be included in the sampling network: MW040 to MW048, MW054R, MW055, MW056, MW057R, MW060, MW061, and MW062. Samples will continue to be analyzed for total chromium, hexavalent chromium, and arsenic using the methods and procedures in the Macalloy QAPP.

6.4.2 Review of 001 Tidal Creek Cap Measurements Data from the 001 Tidal Creek cap thickness measurements conducted in June 2006, June 2007, June 2008, and June 2009 were reviewed for this report. A summary of thickness measurements are presented in Table 6-2 and Figure 6-3. Each event had at least one or more transects with a sand cap thickness less than 18 inches: one transect in 2006, three in 2007, three in 2008, and five in 2009. During the five-year review period, one area was recommended for repair. As described in Section 4.2.3, a portion of the cap near Transect 3 had exposed geotextile fabric and was repaired in December 2008. Subsequently, the June 2009 measurement event indicated the repaired portion of the cap was stable and in good condition.

Additional observations during the 2009 measurement event note that the tidal creek from Transects 6 to 11 had dense marsh grass, making the tidal creek nearly indistinguishable from the surrounding salt marsh.

During the October 2009 First Five-Year Site Inspection, SCDHEC and EPA recommended future measurements to continue every other year (2011 and 2013) until the second five-year review.

6.4.3 Review of Tidal Marsh Plant Survey Data Data from the tidal marsh surveys conducted by Hutton Landscapes in June 2006 and EnSafe in June 2007 and 2008 were reviewed for this report. Hutton Landscapes concluded the survival rate exceeded 70% and the plantings were spreading well in June 2006 (FRAR 2006). The June 2008 survey by EnSafe concluded the average stem density of 5. alterniflora in the restored marsh was 78% of the average stem density in the undisturbed marsh; therefore, satisfying the 70% OCRM success criteria. The June 2008 survey also noted a significant number of new growths and that hand-planted S. alterniflora was no longer distinguishable from the full grown offspring (EnSafe, July 30, 2008).

Photographs of the tidal marsh before and after restoration are included in Appendix E. OCRM success criteria have been met; therefore during the October 2009 First Five-Year Site Inspection, SCDHEC and EPA recommended no future monitoring in the tidal marsh. 38 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

6.4.4 Review of Zone C Sediment Monitoring Data Total chemistry and toxicity data from the sediment monitoring events conducted by EnSafe in October 2006, September 2008, and October 2009 were reviewed for this report. A summary of laboratory analytical results is provided in Table 6-3. Figures 4-3 and 4-4, shows a map of sample locations. One discrete sample location, MACMSYC03, during the October 2007 event had concentrations of total chromium (280 B mg/kg) and total zinc (230 B mg/kg) greater than the protective ranges. Each of the results from October 2007 was flagged with a "B" qualifier by the laboratory, indicating the parameter was observed in the laboratory blank. The "B" flagged results were greater than five times the blank concentration; therefore, the blank concentrations had no effect on the sample results. Analytical results from all discrete and composite samples, including location MACMSYC03, during the October 2006 and October 2009 events had concentrations less than the protective risk ranges for total chromium, nickel, and zinc.

Toxicity results from October 2009 indicated no statistically significant reductions in embryo development (survival or reproductive) were observed between the laboratory control sediment and any sample sediment from Zone C or Rathall Creek. During the October 2009 First Five-Year Site Inspection, SCDHEC and EPA recommended no future monitoring for chemistry or toxicity in Zone C.

6.5 Site Inspection The First Five-Year Site Inspection was conducted on October 16, 2009 by Craig Zeller of the EPA. The Five-Year Inspection Checklist is provided in Appendix F. The site inspection was attended by the following:

Craig Zeller, EPA Sherryl Carbonaro, EPA Chad Tripp, EnSafe Inc. Greg Cassidy, SCDHEC Chuck Williams, SCDHEC Paul Meierer, Macalloy PRP Group Tim Nelson, Macalloy PRP Group Gerald Pouncey, MMM Law

Team members reviewed the scope and performance of each remedial component, walked the Site, and agreed on future monitoring during the next five-year review period. Photographs of the Site during the site inspection are included in Appendix G. _ First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

During the site walk it was noted that the storm water ponds and ditches were overgrown with vegetation, obscuring any potential sediment buildup near the inlets and outlets; otherwise no significant issues were raised concerning the overall protectiveness of the remedy.

6.6 Interviews Interviews with the local community are discussed in Section 6.2 Community Notification and Involvement. Individual interviews of team members were not conducted because group discussions during the site inspection in October 2009 reviewed all significant information to this Five-Year Review.

40 Table 6-1 Groundwater Monitoring Results During the First Five-Year Review Period Geochemistry 1 Laboratory Analytical Results Measurements 1

Well Sample Hexavalent Identification Event Type Fraction Arsenic Barium Cadmium Chromium Chromium Lead Mercury Selenium Silver Turbidity ORP pH MW040 EVENT 1 N T <10U 92 3

Geochemistry LatKjratorv Analytical Results Measurements

Well Sample Hexavalent Identification Event Type Fraction Arsenic Barium Cadmium Chromium Chromium Lead Mercury Selenium Silver Turbidity ORP pH MW047 EVENT 1 N T 9.7 3 84 3 <5U 2900 <1000UX <15U <0.2U 53 2] 9.8 •44 6.32 MW047 EVENT 2 N T 15 70 3 0.92 3 3200 <10000 UX <15U <0.2U <25U 23 32.2 -143 6.99 MW047 EVENT 3 N T 38 73 3 2.6 3 460 <10000 UX <60U <0.2U <50U 5.2 3 0 •111 6.58 MW047 EVENT 4 N T 6.0 3 57 3 0.94 3 5400 1400 <3U <0.2U 22 0.79 3 8 49 6.06 MW047 EVENTS N T 11 59 3 0.75 3 4800 <10000 UX <3U <0.2U 13 1.2 3 81 •44 6.34 MW047 EVENT 5A FD T 3.8 3 4700 220 2 •106 6.5 MW047 EVENT 5A N T 3.9 3 4100 4100 2 -106 6.S MW047 EVENT 6 N T 10 3 4000 <10000UX 104 -61 6.37 MW047 EVENT 7 N T 6.2 3 4500 3700 34.5 -235 9.11 MW047 EVENTS N T 18 1400 <10000 UX 29 -142 6.5 MW047 EVENT 9 N T 14 1400 <10000 UX 10.4 4 6.13 MW04S EVENT 1 N T 7.6 3 72 3

Well Sample Hexavalent Identification Event Type Fraction Arsenic Barium Cadmium Chromium Chromium Lead Mercury Selenium Silver Turbidity ORP pH MWOSS EVENT 1 N T 7.3 3 74 3 <5U 13 <100000 UX <3 U <0.2U

Notes: All units are micrograms per liter (pg/L) N = Normal sample type FD = Field duplicate < 10 U = Compound was analyzed for but not deteaed above the reporting limit of 10 ug/L Reported value was less than the reporting limit but greater than or equal to the method J = detection limit; therefore the concentration was estimated X = Detection limits were elevated due to matrix interference Blank cells indicate the parameter was not analyzed. Bold values indicate the reported value is greater than the total chromiuni cleanup goal of 100 pg/L or the arsenic EPA MCL of 10 pg/L Table 6-2 Zone A Tidal Creek Cap Thickness Measurements During the First Five-Year Review Period Average Cap Thickness (inches)

Transect June June June June Notes: 2006 2007 2008 2009 Mouth of tidal channel, merges vi/lth inain waters of 1 22 28 19 20 ShiDvard Creek. 2 22 17 29 16 3 20 20 25 20 4 11 7 13 12 5 27 21 19 10 Dense marsh grass; indistinguishable from surrounding 6 22 18 17 10 marsh Dense marsh grass; indistinguishable from surrounding 7 24 17 19 18 marsh Dense marsh grass; indistinguishable from surrounding 8 23 26 26 16 marsh Dense marsh grass; indistinguishable from surrounding 9 18 20 20 18 marsh Dense marsh grass; indistinguishable from surrounding 10 19 15 13 18 marsh Dense marsh grass; indistinguishable from surrounding 11 20 24 27 24 marsh Note: Yellow shading indicates thickness less than 18 inches. Table 6-3 Zone C Sediment Monitoring Results during the First Five-Year Review Period Parameter and FRAR Protective Range Total Chromium Nickel Zinc Total (219 to (33 to (132 to Organic Percent Sample Id Location ID Sample Date Sample Type 258) 35.7) 163) Carbon Moisture MACMSYCOlOOl MACMSYCOl 10/20/2006 Discrete 61 17 76 41000 61 MACMSYC01002 MACMSYCOl 9/8/2008 Discrete 82 B 7.3 49 B 4500 43 MACMSYC01003 MACMSYCOl 10/26/2009 Discrete 69 10 70 15000 35 MACMSYC02001 MACMSYC02 10/20/2006 Discrete 110 22 94 18000 56 MACMSYC02002 MACMSYC02 9/8/2008 Discrete 82 B 12 76 B 31000 47 MACMSYC02003 MACMSYC02 10/26/2009 Discrete 63 11 76 17000 48 MACMSYC03001 MACMSYC03 10/20/2006 Discrete 100 16 97 23000 56 MACMSYC03002 MACMSYC03 9/8/2008 Discrete 280 B 31 230 B 8600 70 MACMSYC03003 MACMSYC03 10/26/2009 Discrete 61 9.5 57 5500 35 MACMSYC04001 MACMSYC04 10/20/2006 Discrete 84 12 86 14000 44 MACMSYC04002 MACMSYC04 9/8/2008 Discrete 130 B 17 110 B 22000 62 MACMSYC04003 MACMSYC04 10/26/2009 Discrete 59 8.5 67 10000 38 MACMSYC05001 MACMSYC05 10/20/2006 Discrete 130 17 110 19000 49 MACMSYC05002 MACMSYC05 9/8/2008 Discrete HOB 15 92 8 16000 54 MACMSYC05003 MACMSYC05 10/26/2009 Discrete 72 11 70 12000 42 Discrete MACNSYC05001 MACNSYC05 10/20/2006 Duplicate 100 14 84 15000 43 Discrete MACNSYC05002 MACNSYC05 9/8/2008 Duplicate 91 B 13 87 8 15000 44 Discrete MACNSYC05003 MACNSYC05 10/26/2009 Duplicate 65 10 62 13000 40 MACMSYCClOOl Composite 10/20/2006 Composite 95 16 92 NA 55 MACMSYCC1002 Composite 9/8/2008 Composite 94 B 13 81 B NA 43 MACMSYCC1003 Composite 10/26/2009 Composite 79 12 74 NA 43

Notes: mg/kg = Milligrams per kilograms NA = Not applicable B = Indicates the parameter was observed in the laboratory blank Yellow highlighted cells exceed protective range. <1 ""^iJT"

MW060 4.39 ^

W1W040 1 MW041 -d). ^Sl

W042 4.93»

MW044 A 4.90

•. MW045 4.64 *•. v.^W0<7 -^ •>:f"5.02*.

MW046 I ^ 4.71 .

•.% MW049 • 4.03

W050 i 1^ 4.00 'Wl^^ MWOSS •. 4.69 * MWOS 3 . 6.18

MW057R 10.18 MWOSS 9-55 j^ iVlWObJIR.**. *. wrofo58

ri-.

Legend N Event 9 Groundwater Elevations (feet) Notes: Elevations at IVIW057R and MW058 are approximated FIGURE 6-2 ^^^~ Contour based on site topography. EVENT 9 Groundwater elevations collected 10/22/09. ~ — Inferred Contour Groundwater elevations are shown at each well in feet. SHALLOW GROUNDWATER Vertical datum: NGVD1929 Groundwater Remedial Action (2004-2005) ELEVATION CONTOURS Topography surveyed by Thomas and Hutton Engineering Co. 10/06/2006 — — Supplemental Trenching (2008) I MACALLOY CORPORATION NPL SITE • Groundwater Flow Direction CHARLESTON, SC

REQUESTED BY: CT BY: CT EAISAFE 100 200 400 I Feet

Date: 1/2010 K:\GIS\Macalloy\Firsl Five Yr Review First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

7.0 TECHNICAL ASSESSMENT The following sections present an assessment of the protectiveness of the implemented remedies at the Site, particularly with respect to the following three questions, in accordance with the EPA Comprehensive Five-Year Review Guidance (June 2001):

• Question A — Is the remedy functioning as intended by the decision documents?

• Question B — Are the exposure assumptions, toxicity data, cleanup levels, and RAOs used at the time of remedy selection still valid?

• Question C — Has any other information emerged that could call into question the protectiveness of the remedy?

7.1 Question A: Is the remedy functioning as intended by the decision documents? The functionality of each component to the site-wide remedial action is presented in the following sections.

7.1.1 Radiological Material Yes, the remedy is functioning as intended by the decision documents.

Remedial Action Performance Based on the performance standards and quality control presented in the FRAR, cleanup goals were attained by this remedial action. All soil and debris that were identified in the Final Design with elevated levels of gamma radiation was excavated and disposed of offsite at the time of the remedial action.

System Operations/O&M None

Opportunities for Optimization None

Early Indicators of Potential Issues None

41 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Implementation of Institutional Controls and Other Measures Institutional controls have been placed on the Site to restrict land use and groundwater use. Section 4.7 and Appendix B presents specifications of these controls.

7.1.2 Zone A Sediment Removal Yes, the remedy is functioning as intended by the decision documents.

Remedial Action Performance Based on the performance standards presented in the FRAR, and data from the 001 Tidal Creek Cap thickness monitoring reports during the first five-year review period, the remedial action continues to operate and function as designed. Benthic organism exposure to contaminated sediment in the Zone A 001 Tidal Creek was mitigated by the excavation and disposal of sediment to a depth of 24 inches, and with the placement of a geotextile and 18 inch thick sand cap.

System Operations/O&M Cap thickness monitoring has been and should continue to be effective in documenting the status of the cap and identifying any issues that may need repair. In 2008, yeady monitoring identified a section of the cap that was damaged and a repair was subsequently completed.

Stem density surveys of the hand-planted grass in the disturbed tidal marsh were effective in evaluating the status of restoration. OCRM success criteria for plant restoration have been met; therefore, no future monitoring is recommended.

Opportunities for Optimization The frequency of cap thickness monitoring has been recommended for optimization. Monitoring during the second five-year period is recommended every other year in 2011 and 2013.

Early Indicators of Potential Issues One small section of the sand cap was repaired and an increasing number of transects with thicknesses less than 18 inches have been observed each year. This was expected during the Final Design because sand transportation in a marine, tidal ecosystem is a natural process. O&M was recommended during the second five-year period to monitor and maintain the protectiveness of the remedy.

42 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Implementation of Institutional Controls and Other Measures Institutional controls have been placed on the Site to restrict land use and groundwater use. Section 4.7 and Appendix B present specifications of these controls.

7.1.3 Zone C Sediment Yes, yearly monitoring has functioned as intended by the decision documents. No remedial action was required by the ROD.

Remedial Action Performance None

System Operations/O&M Monitoring during the five-year review period was effective at evaluating the condition of Zone C sediment.

Opportunities for Optimization During the five-year review period, concentrations of total metals in October 2009 were below protective ranges established by the FRAR and toxicity tests resulted in no adverse effects to benthic organisms; therefore, no additional monitoring is recommended for Zone C.

Early Indicators of Potential Issues No early indicators of potential issues were observed during the review of monitoring data from the first five-year review period.

Implementation of Institutional Controls and Other Measures Institutional Controls were not required for Zone C Sediment.

7.1.4 Groundwater Yes, the remedy is functioning as intended by the decision documents.

Remedial Action Performance The remedial action continues to perform, as evident by total chromium cleanup goals being achieved at 19 of 23 monitoring wells. Furthermore, reduction has been observed following the construction of supplemental PRBs in the vicinity of 3 wells where goals have not been met. As previously discussed in Section 4 and as shown on Figure 4-1, five plumes of total chromium contaminated groundwater above the cleanup goal were identified during the RI. 43 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Based on groundwater monitoring during the first five-year review period, two of these original plumes (Plume III and IV) are no longer present, and two plumes (Plumes I and V) have been significantly reduced in size and concentration. Figure 7-1 presents isoconcentratons for total chromium above the cleanup goal during Event 9.

The largest of the plumes during the RI, Plume I, covered an area of approximately 15 acres and had hexavalent chromium concentrations up to 10,000 pg/L. Based on Event 9 data, only one well MW047 in the former Plume I vicinity had a total chromium concentration (1400 pg/L) above the cleanup goal. The PRBs installed during the 2008 supplemental groundwater treatment described in Section 4.4 are expected to remain active at converting hexavalent chromium to trivalent chromium over the next five years; thereby further accelerating the reduction of total chromium at Plume I (MW047) over the next five years.

During the RI, Plume V covered an area of approximately 1/2 acre and had total chromium concentrations up to 10,000 pg/L. Based on monitoring data to date, the only well in the former Plume V vicinity where total chromium was reported above the cleanup goal is MW054R, where the exceedance is associated with a single data point. This concentration is further suspect, since the sample in question was collected from a well installed to replace MW054, where historical total chromium results were well below the cleanup goal.

Based on Event 9 monitoring data, concentrations in Plume II remain above the cleanup goal at levels similar to those shown in the ROD. It should be noted that the northern extent of this plume was further delineated during the DPT assessment (Event 6A) conducted in July 2008, discussed in Section 4.4. The PRBs installed during the 2008 supplemental groundwater treatment described in Section 4.4 are expected to remain active at converting hexavalent chromium to trivalent chromium over the next five years; thereby further accelerating the reduction of total chromium at Plume II (MW060 and MW041) during the next five years.

System Operations/O&M The long term groundwater monitoring program has been and should continue to be effective at evaluating the performance of the soil and groundwater remedy and identifying any response actions.

44 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Opportunities for Optimization During the October 2009 First Five-Year Site Inspection, SCDHEC and EPA recommended groundwater monitoring to continue semi-annually for the next two years and then annually for the following three years until the second five-year review. Monitoring wells MW049, MWOSO, MWOSl, MW0S2 and MW0S9 have consistently demonstrated concentrations of chromium below the established cleanup goal; therefore they will be dropped from the long-term monitoring network, but will not be abandoned at this time in case additional samples are required in the future. The following 16 monitoring wells were recommended for the sampling network: MW040 to MW048, MW0S4R, MWOSS, MW0S6, MW0S7R, MW060, MW061, and MW062. Samples will continue to be analyzed for total chromium, hexavalent chromium, and arsenic using the methods and procedures in the Macalloy QAPP.

Early Indicators of Potential Issues Total chromium concentrations above the cleanup goal during the five-year review period at MW041, MW060, MW061, and MW047 have been addressed by completing the supplemental groundwater treatment in December 2008. Groundwater will continue to be monitored and the remedy evaluated for potential issues during the second five-year review period. Potential issues with the remedy in the vicinity of MW0S4R will be evaluated by collecting additional total chromium data from MW054R during the second five-year review period.

Currently, MW054R cannot be re-sampled, nor concentrations verified because the well is obstructed with road fill. MW054R is located on property owned by Sonoco. MW054R should be located, condition assessed, and re-sampled if possible. Additionally, the well's flush mount casing should be raised to accommodate future road elevation changes. This property contains deed restrictions that require Sonoco to be respectful of the remediation system.

Implementation of Institutional Controls and Other Measures Institutional controls have been placed on the Site to restrict land use and groundwater use. Section 4.7 and Appendix B presents specifications of these controls. Groundwater beneath the Site may not be used for drinking or irrigation purposes. Businesses located on the Site attain drinking water from the city water supply. Current and future land use at the Site is limited to industrial and commercial.

7.1.5 Soil Yes, the remedy is functioning as intended by the decision documents. In accordance to the ROD, the performance of the soil remedy is evaluated by groundwater monitoring.

45 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

7.1.6 Surface Water/Storm Water Yes, the remedy is functioning as intended by the decision documents. Remedial Action Performance Construction of the storm water management system was considered complete upon signing of the PCOR in September 2006. Remedial performance standards were met and documented in the FRAR.

On July 16, 2008, Magnolia Development, LLC, received notification from SCDHEC that storm water monitoring could be terminated because monthly monitoring data had consistently met the performance criteria established by the SCDHEC.

System Operations/O&M As mentioned above, monitoring was terminated because data consistently met the performance criteria established by the department.

Opportunities for Optimization None.

Early Indicators of Potential Issues During the site inspection, it was noted that vegetation in the storm water ponds and ditches were overgrown, obscuring the evaluation of potential sediment buildup in the storm water pipe inlets and ponds.

Implementation of Institutional Controls and Other Measures Institutional controls have been placed on the Site to restrict land use and groundwater use. Section 4.7 and Appendix B presents specifications of these controls. Current and future land use for the Site is industrial and commercial use only.

7.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and RAOs used at the time of the remedy selection still valid? Yes. The exposure assumptions, toxicity data, cleanup goals and RAOs specified in the ROD are still relevant and applicable. The following sections review each component of this question.

46 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

7.2.1 Changes in Standards and To Be Considered (TBCs):

• Arsenic was identified as a COC in shallow groundwater during the RI, but was not retained for evaluation in the FS because the exposure point concentration (EPC) for arsenic (9 pg/L) was less than the MCL of 50 pg/L, and the hazard quotient (HQ) for arsenic was insignificant when compared to the HQ for hexavalent chromium. In January 2006, the MCL for arsenic changed from SO pg/L to 10 pg/L, after the ROD was published in 2002. This change in MCL would not affect the remedy selection because the new MCL of 10 pg/L would remain less than the EPC, and the HQs would be unchanged.

• No other standards identified in the ROD or newly promulgated standards call into question the protectiveness of the remedy

• TBCs used in selecting cleanup goals at the Site have not been changed that could affect the protectiveness of the remedy

7.2.2 Changes in Exposure Pathways:

• Land use or expected land use on or near the Site has not changed.

• No new human health or ecological routes of exposure or receptors have been newly identified or changed in a way that could affect the protectiveness of the remedy.

• No new contaminants or sources have been identified at the Site.

• No unanticipated toxic byproducts of the remedy not previously addressed by the decision documents have been discovered at the Site.

• Physical site conditions or the understanding of these conditions have not changed in a way that could affect the protectiveness of the remedy.

47 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

7.2.3 Changes in Toxicity and other Contaminant Characteristics:

• In December 2009, the EPA updated the toxicity based screening value for hexavalent chromium due to a provisional change in the oral slope factor at the California Office of Environmental Health Hazard Assessment and New Jersey Department of Environmental Protection. The recent development of a provisional oral slope factor for hexavalent chromium has not been adopted by the EPA's IRIS database, which is the primary source of slope factors for risk assessment. Regardless, these changes would not affect the protectiveness of the remedy because the soil and groundwater cleanup goals for total and hexavalent chromium were based on the total chromium MCL of 100 pg/L.

• Contaminant characteristics have not changed in a way that could affect the protectiveness of the remedy

7.2.4 Changes in Risk Assessment Methods: Standardized risk assessment methodologies have not changed in a way that could affect the protectiveness of the remedy.

7.2.5 Expected Progress towards Meeting RAOs: Each RAO is listed below with a discussion on the expected progress towards meeting the RAO.

Remediate shallow groundwater zones with the highest concentrations of hexavalent chromium to minimize long-term threats and limit hexavalent chromium migration into Shipyard Creek. It is anticipated that the soil and groundwater remedies completed in 2006 and the supplemental groundwater treatment in 2008 will fully satisfy this RAO during the next five years. EPA pilot studies suggested that enhanced in situ reduction would require several years to completely reduce the highest hexavalent chromium concentrations below the cleanup goal.

Residual concentrations of total chromium above the cleanup goal in Plume I are isolated to MW047 and not migrating into Shipyard Creek. This is indicated by total chromium concentrations not detected above the reporting limit at MW04S and MW044. Residual concentrations of total chromium above the cleanup goal in Plume II are isolated to MW060 and MW041 as shown by the DPT assessment conducted in July 2008. Furthermore, since the groundwater flow direction in this vicinity is toward the north, it is unlikely that Plume II will migrate into Shipyard Creek.

48 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Prevent future site worker exposure to unacceptable hazard levels in groundwater. The RI concluded that unacceptable hazard levels in the groundwater were from exposure to hexavalent chromium. Progress towards meeting this RAO specific to hexavalent total chromium is presented above.

Remediate soil that leaches hexavalent chromium to groundwater and surface water at concentrations hazardous to human health and the environment. The FRAR documented that the soil remedial action was completed in accordance to the performance standards and soil cleanup criteria established by the ROD and Final Design. Progress towards meeting the groundwater RAO is presented above. On July 16, 2008, storm water monitoring was terminated by SCDHEC because monthly monitoring data had consistently met the performance criteria established by the department.

Mitigate offsite hexavalent chromium discharges in storm water to Shipyard Creek through a combination of the aforementioned remediation measures and a comprehensive site-wide storm water management plan. The comprehensive site-wide storm water management plan was completed in September 2006.

Manage storm water discharges of toxic inorganic compounds in accordance with the comprehensive storm water management plan to protect ambient saltwater quality in Shipvard Creek. The comprehensive site-wide storm water management plan was completed in September 2006.

Remediate soil and debris that produce elevated levels of gamma radiation to mitigate current exposure pathwavs. All radiological soil and debris identified in the ROD with elevated levels of gamma radiation was removed in March 2005 in accordance to the Final Design.

Mitigate exposure of benthic organisms to contaminated sediments in the Outfall 001 Tidal Creek. The Zone A 001 Tidal Creek sediment remedy was completed in accordance to the performance standards established in the Final Design. Contaminated sediments were excavated from the tidal creek to 24 inches below grade, and an 18 inch thick geotextile/sand cap was placed to isolate the limited deeper contaminates identified at 36 inches below grade.

49 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

7.3 Question C: Has any other information come to light that could call into question the protectiveness of the remedy? No new ecological risks, natural disasters, or other information has been identified at the Site to question the protectiveness of the remedy.

7.4 Technical Assessment Summary According to the data reviewed and the Site inspection, the comprehensive Site remedy is functioning as intended by the ROD. RAOs selected for the Site are still valid and have been met for the radiological debris area, storm water, site-wide soil. Zone A Tidal Creek sediment, and Zone C sediment. The ongoing groundwater remedy via in situ chemical reduction is functioning and has effectively reduced most total chromium concentrations below the cleanup goal. The groundwater remedy has limited contaminate flow to Shipyard Creek. Areas with residual chromium above the cleanup goal are expected to have additional reduction during the next five years.

There have been no changes in exposure assumptions, toxicity data, risk assessment methods, and cleanup goals used at the time of remedy selection that would affect the protectiveness of the remedy. Current and planned future land use has not changed, nor is there any other information that calls into question the protectiveness of the site-wide, comprehensive remedy.

50 MT-7^^ TIDAL CREEK REMEDIATION (AVG 18") CAP THICKNESS MEASUREMENT TRANSECT (W/ CAP THICKNESS IN INCHES)

TIDAL CREEK SEDIMENT EXCAVATED AND CAPPED WITH 18" THICK GEOTEXTILE AND CLEAN SAND

APPROXIMATE LOCATION OF TIDAL MARSH RESTORATION

'MT-1 AVG. 20")

SCALE IN FEET

FIGURE 6-3 YEAR 4 CAP THICKNESS MEASUREMENTS FIVE YEAR REVIEW REPORT

(800) 588-7962 MACALLOY CORPORATION SITE MEMPHIS. TENNESSEE ARKANSAS FLORIDA KENTUCKY MICHIGAN MISSISSIPPI CHARLESTON, SOUTH CAROLINA OHIO SOUTH CAROLINA TENNESSEE TEXAS VIRGINIA REPUBLIC OF KAZAKHSTAN SLOVAK REPUBLIC Date: OIFEBIO DWG Name:7205R004 4

MW043 E1 =2.1J E2 = 7.2J E3 = 6,4J E4 = 8.1J E5 = 4.7J E6= 15 E7 = 8.3J E8 = 64 E9=37 MW042 E1 = 1.6J E2 = 1.1J E3 = ND E4 = ND E5 = ND E6 = ND E7 = ND E8 = ND E9 = ND

W049 E1 - 3.aj E2 - 80.0 wm^^i E3 - 48 E5A=17 E4= 150 CHARLESTON E6 =8.5J •. E5 - 17 COUNTY E7 =6.3J E6 = 36 (R/W E8 =11 E7 - 9.5J VARIES) E9 = 17 E8 - 13 \

^^wo59-i t1 = 1.8J E2=1.8J E3-ND E4 = ND E5=ND E6= 1.5J E7 = 2.8J E8 = ND

MW054R —V .MW057 (ABANDONED) a E8 = 3900 El - 0.B2J E2 - 1.4J E3 - ND E4 - ND E5 - ND MW055 — El == 1J E2 == 0.68J 2 O E3 == ND E4 == ND E5 -ND E7- = ND E9- = ND

MW054(ABANDONED)

CHARLESTON \ COUNTY (R/W VARIES) NOTES:

E9=17 EVENT 9 TOTAL CHROMIUM CONCENTRATION OF 17ppb RED TEXT INDICATES THE CONCENTRATION EXCEEDED THE CLEANUP GOAL OF lOOppb ND NOT DETECTED LEGEND: APPROXIMATE SCALE IN FEET TOTAL CHROMIUM ISOCONCENTRATION LINES (ppb) FROM OCTOBER 2009 GROUNDWATER MONITORING (EVENT 9) FIGURE 7-1 o TOTAL CHROMIUM ISOCONCENTRATION LINES CM TWOS® TEMPORARY GROUNDWATER MONITORING WELL (2008) ABOVE CLEANUP GOAL FROM OCTOBER 2009 GROUNDWATER SAMPLING MWO6O-0- LONG TERM GROUNDWATER MONITORING WELL FIRST FIVE YEAR REVIEW REPORT I MACALLOY CORPORATION SITE GROUNDWATER REMEDIAL ACTION: CHARLESTON. SOUTH CAROLINA REQUESTED BY: CT. INJECTION 2004-2005 DRAWN BY: E.R. TRENCHING 2005 DWG DATE: OIFEBIO SUPPLEMENTAL TRENCHING 2008 (800) 588-7962 DWG NO: 7205R007 UEMPHIS. TENNESSEE First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

8.0 Issues Table 8-1 presents any issues related to current site operations, conditions, or activities, noting which issue, if any, currently prevent the remedy from being protective.

51 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Table 8-1 Issues Affects Current Affects Future Protectiveness Protectiveness Issues (Y/N) (Y/N) Zone A 001 Tidal Creek Cap: One small section of the sand cap was repaired and an increasing number of transects with thicknesses less than 18 inches have been observed each year. O&M was recommended during the N N second five-year period to monitor and maintain the protectiveness of the remedy.

Tidal Marsh Plant Surveys: Stem density surveys of the hand-planted grass in the disturbed tidal marsh were effective in evaluating the status of restoration. OCRM success criteria for plant restoration have been met; N N therefore, no future monitoring is recommended.

Zone C Sediment Monitoring: During the five-year review period, concentrations of total metals in October 2009 were below protective ranges established by the FRAR and toxicity tests resulted in no adverse effects to benthic N N organisms; therefore, no additional monitoring is recommended for Zone C.

Groundwater- Monitoring Optimization: During the October 2009 First Five-Year Site Inspection, SCDHEC and EPA recommended groundwater monitoring to continue semi-annually for the next two years and then annually for the following three years until the second five-year review. Monitoring wells MW049, MWOSO, MWOSl an MW059 N N have consistently demonstrated concentrations of chromium below the cleanup goal.

Groundwater- MW054R: Elevated concentrations of total chromium above the groundwater cleanup goal were reported at MW054R, during Event 8 in April 2009. This well could not be re-sampled, nor concentrations verified during Event 9 sampling in October 2009 as the well was obstructed with road fill. N Y MW054R is located on property owned by Sonoco. This property contains deed restrictions that require Sonoco to be respectful of the remediation system.

Groundwater- Well Surveys: A horizontal and vertical professional coordinate survey has not been performed N N for wells MW054R, MW056, MW057R, and MW0S8. This data is needed to adequately determine groundwater elevations and flow direction on the site.

Surface Water/ Storm Water Management System: During the site inspection, it was noted that vegetation in N N the storm water management ponds and ditches were overgrown, obscuring the evaluation of sediment buildup.

52 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

9.0 Recommendations and Follow-up Actions Table 9-1 presents the required or suggested improvements to current site operations, activities, remedies, or conditions.

53 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

Table 9-1 Recommendations and Follow-up Actions Affects Recommendations and Follow-up Oversight Protectiveness Issue Party Responsible Milestone Date Actions Agency (Y/N) Current Future Zone A 001 Tidal Monitor cap thickness in 2011 and 2013 Macalloy PRP Group EPA/ SCDHEC July 30, 2015 N N Creek Cap Tidal Marsh Plant Completed/ Discontinue Macalloy PRP Group EPA/SCDHEC July 30, 2008 N N Surveys Zone C Sediment Completed/ Discontinue Macalloy PRP Group EPA/ SCDHEC December 8, 2009 N N Monitoring Continue long term effectiveness groundwater monitoring on semi-annual basis for next two years and then annually thereafter, depending on results. MW049, Groundwater- MWOSO, MWOSl, MW0S2 and MW059 will Monitoring be dropped from the long-term monitoring Macalloy PRP Group EPA/SCDHEC June 1, 201S N N Optimization network, but will not be abandoned. The following 16 wells are recommended for the sampling network: MW040 to MW048, MW0S4R, MWOSS, MW0S6, MW0S7R, MW060, MW061, and MW062. Locate, assess condition, and re-sample Groundwater- MW0S4R if possible. Raise flush mount Sonoco EPA/SCDHEC September 1, 2010 N Y MW054R casing to accommodate future road elevation changes. Groundwater- Well Attain a horizontal and vertical professional Surveys coordinate survey of MW0S4R, MW056, Macalloy PRP Group EPA/SCDHEC September 1, 2010 N N MW0S7R, and MWOSS. Surface Water/ Evaluate vegetation and sediment buildup in Storm Water Shipyard Creek the storm water management system and EPA/ SCDHEC December 1, 2010 N N Management Associates clean if necessary. System

54 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

10.0 Protectiveness Statement The remedy at the Macalloy Site currently protects human health and the environment in the short- term because the following were completed to meet RAOs:

• Radiological debris and soil was removed.

• Contaminated sediment in Zone A was removed and a clean sand cap was constructed to isolate the minimal deeper contaminants.

• Concentrations of hexavalent chromium in soil were reduced below 23 mg/kg.

• A comprehensive storm water management system was constructed to mitigate offsite storm water discharges of toxic inorganic compounds.

• Institutional controls and restrictive covenants were executed for the Site that limit future use to commercial/industrial purposes, and prohibit the use of groundwater underlying the property.

The soil and ongoing groundwater remedy have reduced the highest concentrations of hexavalent chromium in the shallow groundwater; however, in order for the remedy to be protective in the long- term, monitoring well MW054R needs to be evaluated and all site shallow groundwater must show sustained concentrations of hexavalent chromium below the cleanup goal of 100 pg/L.

55 First Five- Year Review Report Macalloy Corporation NPL Site Charleston County, South Carolina June 24, 2010

11.0 Next Review The Second Five-Year Review for the Macalloy NPL Site is required to be completed in July 30, 2015, five years after the signature date of this review.

56 Appendix A Termination of Storm Water Monitoring Letter from South Carolina Department of Health and Environmental Control HL).-\Rn-. r~\ TT i; r-^ BOARD-. I'.iu|r Au,;litrv, 111 j^-—.-Jg^^^r—^^ H-.riry CScutl

'^"'"''^" ^T^T^TTr fenf?^ fT^-rrS '"'''™" "^ •^'''''-•'" S':t:rct.irv '^. Ejrl Hutirer, CiMnmisiiuner (..ijlrjn.iti R Bu>;L-hoii»;c. MD l''rrii>ioTi:ig ,nidprohrtitig rhc' l'f,iltli nf rl]i' puljlic niiri liif t'yii'iroiinu'ur

July 16, 2008

Mr. Michael A. Costa Magnolia Development, LLC 1601 Oceanic Street Charleston, SC 29405

RE: Termination of Storm water Monitoring Macalloy Superfund Site Charleston County

Dear Mr. Costa:

This letter is in response to your request to terminate the storm water monitoring at the Macalloy Superfund Site (MSS). Monthly storm water monitoring began in August 2006. I have reviewed the monitoring data submitted during the monthly sampling events and conclude that the storm water management activities have consistently met the established numerical criteria and limits established by this Department. Also, the storm water management system has mitigated the discharge of contaminants from the MSS into Shipyard Creek. Therefore, beginning July 2008 storm water monitoring requirements will no longer be required.

If you have any questions please call me at 803.898.4235 or e-mail me at sw vgercw(5)dhec.sc. gov.

Sincerely,

Butch Swygert Environmental Engineer Associate Industrial Wastewater Permitting

cc: Ms. Ashley Auerbach, Region 7/Charleston EQC District Office (via e-mail) Mr. Tim Homosky, Bureau of Land & Waste Management (via e-mail) Mr. Craig Zeller, P.E., U.S. EPA - Region 4, Superftjnd Division Mr. Tim Nelson, Macalloy Site PRP Group (via e-mail) Mr. Larry Setzler, GEL Engineering LLC

so \\ r n K:. A R C>L i N .\ DEP .A RT M E N r OF HE.\ LT n .^ N D EN \' i R D .N M E NT ,\ L CO N T R O i. •2600Bn)l,Su-eei •Coli"inibi;K.SC:2yi'01 • Plioner80:V)89.S-y!;t'Mv\vw Appendix B Restrictive Covenant fiii 0 585PG298 STATE OF SOUTH CAROLINA ) ) DECLARATION OF COVENANTS COUNTY OF CHARLESTON ) AND RESTRICTIONS

THIS DECLARATiON OF COVENANTS AND RESTRICTIONS (Declaration) is made and entered into this aa, day of May of 2006, by Ashley II of Charleston, LLC, a South Carolina limited liability company (hereinafter referred to as Ashley II) and the South Carolina Department of Health and Environmental Control (Department).

RECITALS

WHEREAS, this Declaration of Covenants and Restrictions is entered into pursuant to S.C. Code §44-56-200 et seq.; and

WHEREAS, Ashley II is the owner of certain real property in Charleston County, South Carolina, more particularly described in Exhibit A attached hereto and incorporated herein by reference ("Property"); and

WHEREAS, contaminants in excess of allowable concentrations for unrestricted use remain at the Property; and

WHEREAS, the Property was previously used as a ferrochromium alloy manufacturing plant and is currently designated as Superfund Site SCD003360476 pursuant to the Comprehensive Environmental Compensation and Liability Act ("CERCLA"), 42 U.S.C. Section 9601 et seq.; and

WHEREAS, the Property Is the subject of Consent Agreement 05-06-HW (CA) entered into to by the Department and Ashley II, pursuant to the Comprehensive Environmental Response Compensation and Liability Act (CERCLA), 42 U.S.C. §§ 9601. et seq. and the South Carolina Hazardous Waste Management Act (HWMA), S.C. Code Ann. § 44-56-200.

WHEREAS, the Property has undergone and is undergoing remediation pursuant to the United States Environmental Protection Agency ("EPA") Record of Decision relating to the Macalloy Corporation Site, signed August 21, 2002, by the Director of the Waste Management Division, EPA Region 4 ("ROD") and the Consent Decree between the United States of America and Macalloy Corporation and The BOC Group, Inc., Civil Action Number 2 04 1201 18 (the "Consent Decree");

WHEREAS, the remedial and other work required under the ROD and Consent Decree shall hereafter be referred to as the "Consent Decree Work"; and

^os-on^o M 0 585PG299

WHEREAS, the Property may be used for certain purposes without further remediation beyond the Consent Decree Work and requires that certain restrictions are placed on development and use of the Property; and

WHEREAS, Ashley II has agreed to impose restrictions on the manner in which the Property may be developed; and

WHEREAS, it is the intention of all parties that EPA is a third party beneficiary of said restrictions and said restrictions shall be enforceable by the EPA, Department, and their successor agencies.

NOW, THEREFORE, KNOW ALL MEN BY THESE PRESENTS that Ashley II hereby declares and covenants on behalf of itself, its heirs, successors, and assigns that the Property described in Exhibit A shall be held, mortgaged, transferred, sold, conveyed, leased, occupied, and used subject to the CA dated March 8, 2005, to include the following restrictions, which shall touch and concern and run with the title to the Property.

1. Ashley II hereby covenants for Itself, its heirs, successors and assigns that the Property shall not be used for the following purposes: residential, agricultural, child day care facilities, schools, or elderly care facilities. Further. Ashley II hereby covenants for itself, its heirs, successors, and assigns that the Property shall not be used for recreational purposes unless the specific recreational activity is approved by the Department or its successor agencies.

2. Ashley II covenants for itself, its heirs, successors and assigns that groundwater beneath the Property may not be used for drinking or irrigation purposes without prior approval from the EPA and the Department or their successor agencies. Groundwater wells may be installed and maintained for the purpose of groundwater monitoring and sampling and as may othenwise be required by law. Any said ground water monitoring, sampling or remediation wells shall be kept capped and locked, except when in active use to monitor, assess, or remediate water quality on or under the Property.

3. Ashley II covenants for itself, its heirs, successors and assigns that the EPA, the Department, their successor agencies, and all other parties performing response actions under EPA's or the Department's oversight shall be provided reasonable access for (i) inspecting the property (ii) monitoring, (ill) verifying information, (iv) sampling the property, (v) assessing the need for additional response or quality control practices, (vi) implementing the Consent Decree Work, (vii) inspecting and copying records, (viii) assessing the responsible party's compliance, (ix) assessing compliance with existing land use I 0 585PG300

restrictions under the Consent Decree and this Declaration, or to take samples as may be necessary to enforce the this Declaration.

4. The covenants and restrictions set forth herein shall run with the title to the Property and shall be binding upon Ashley II, its heirs, successors and assigns. It is expressly agreed that the Department shall have the right to enforce these covenants and restrictions upon Ashley M, its successors, and assigns. Ashley II and its heirs, successors, and assigns shall include the following notice on all deeds, mortgages, plats, or any legal instruments used to convey any interest in the Property (failure to comply with this paragraph does not impair the validity or enforceability of these covenants):

NOTICE: This Property is Subject to Declaration of Covenants and Restrictions and any subsequent Amendments Recorded at Book . Page , Register of Mesne Conveyance Office for Charleston County, South Carolina.

5. Ashley It, its heirs, successors, assigns and any subsequent purchaser of the Property shall submit to the EPA and the Department a statement of maintenance of the covenants and restrictions as set forth above annually on May 31^' of every year. This reporting requirement is the obligation of each owner of the Property, or portion of the Property, as of May 31 of each year. Once title to all or a portion of the Property has been conveyed by Ashley II or any subsequent owner, such predecessor in title shall no longer have any responsibility for submission of the Report with respect to the portion of the Property it previously owned.

6. This Declaration shall remain in place until such time as the Department has made a written determination that the covenants and restrictions set forth herein are no longer necessary. The Department shall not consent to any such termination unless the requirements of the ROD have been met. This Declaration shall not be amended without the written consent of the Department or its successor agency. The Department shall not consent to any such amendment or tennination without the consent of EPA.

7. It is expressly agreed that EPA is not the recipient of a real property interest but is a third party beneficiary of the Declaration of Restrictive Covenants, and as such, has the right of enforcement.

8. This Declaration only applies to the Property expressly identified in Exhibit A and does not impair the Department's authority with respect to the Property or other real property under the control of Ashley II. d 585PG30I

IN WITNESS WHEREOF, Ashley II of Charleston, LLC has, caused this instrument to be executed as of the date first above written,

WITNESSES: ASHLEY II OF CHARLESTON, LLC A SOUTH CAROLINA LIMITED LIABILITY COMPANY

,ALUO6A<3^ By: ifoegfr? L. Cis^r?^

Robert L Clement, III Authorized Member

STATE OF SOUTH CAROLINA ) COUNTY OF CHARLESTON ) ACKNOWLEDGEMENT

JsxKk^h Ht^ueli (Notary Public), do hereby certify that, /^^tor Cust^^e^ __, an authorized representative of the Ashley II of Charleston, LLC, personally appeared before me this day and acknowledged the due execution of the foregoing instrument, on behalf of the Ashley II of Charleston, LLC. Witness my hand and official seal this dc^ day of I' l^^OA . 2006.

^.

•«•.»* ^^ — ji^: ^ /* ft." : ^ C Jbllc for South Carolina ^ ^-^ ly Commission Expires: G/7/30/Y^ '''•""^''t^'-^ BS 0 585PG302

IN WITNESS WHEREOF, the Department has caused this instrument to be executed as of the date first above written.

WITNESSES: South Carolina Department of Health

and Environmentanmentail Control By: Z Robert W. King, Jr., P.E., Deputy Commissioner, Environmental Quality Control J^nH.y X"'KQyx^3^ South Carolina Department of Health and Environmental Control

STATE OF SOUTH CAROLINA ACKNOWLEDGEMENT

COUNTY OF RICHLAND )

I. "3/)/ln,>^'1^f^Z-j/^riiJ ]^. JXJyj^Uhi^kohNl (Notary Public), do hereby certify that, Robert W. King, Jr.. P.E., Deputy Commissioner Environmental Quality Control of the South Carolina Department of Health and Environmental Control, personally appeared before me this day and acknowledged the due execution of the foregoing instrument.

Witness my hand and official seal this *2^ day of

My Commission Expires: '•'- I M^jV '.'' ,• 0 585PG303

EXHIBIT A k 0 585PG30I* EXHIBIT A (Description of Real Estate)

. (Attached to Contract of Sale between MacaUoy Corporation, Seller, and Ashley II of Charleston, LLC, Purchaser)

PARCEL I; Ad that piece, parcci or tract of land, situaie, lying and bdr^ in (he Cnuoty of Chadcston, Stale of SouHi Cajolina, casi cf Meeting &UteA Road, and wcsl ofSiiipyzid Cieek, and having stich size, sbapc, ffircBmaoDs, end biititng? and boundingt as arc more clearly fibORTi end dclincalcd on a plal thereof bearing legend- 'boundary Plat ss shown on existing Plata end Records of Property of Ainio AUoys Division Airco, Inc.", dated Joly 12, l?77, by Cnnunings and McCrady. Inc.. EngineeiSs >ad recorded in the ICMXl Office for Charicston Cbunty in Plaj Book A J. a: Page 67, which said pla is hereby made a part and parcel benoi, refetcoce to which said plat is hereby made fat a. more Atll and comp?ete descripiioD. PARCH. 2: All thai cateia piece, parcel oi liact of hmd. simate, lyiAg and being iji the North Charleston Sewer Dtslrict, formerly St. Philip's and SL Midtael's Pariah, in ChHiteiton County, State of South Cuolina. kaawn and designated as Trad "XT, unca^uring and canlairung I 40 scies. all of'which is more hilly shown and deSinoaieA on a plat made by DsrvU & Floyd Engineers, Inc., dated March 13, 1979, erJrtled "Plat showing Tract C. ;^ Property of Seaboard Coast line Raiboad Co., abotil. to be cooveyod to Aiico, faa, locBted ofT Meeting Street. Charleston County, rcconied in Plat Book AN at ?a^ 103, re&fciice to which said plat is hereby made far a marc full and oon^lete descnption.

Sfive and excepting, howevw, from the tbo« propxirty lb6 etil! inajih which contaiiaj 17 acres more or lest tkle to wliicli shall teniain La the asmc of Seller. If all or any portion of Ihe salt njBifsh is not conveyed to KOAA by ScHef. Scllff shall convey at DO coa lo ths Purcl)U«r all or Ihe remaining portion of the aolt nuFEh to Purchase- by qui: claim deed within 90 diys foUovvios cousp]eie resolution of the claim by NOAA &nd others tor alleged damages to natural rcGourccs.

Being the same property conveyed to Macalloy Corporation by deed of Airco, Inc. dated July 11,1979 and recorded Jidy 17,1979 in hook U 119 at Page 72.

»20O3-01M I iaVMI kJ in COUMBlAmfiirl 0 585PG3Q5 SCHEDULE A-1 f (Tax Map)

(Attached to Cpntraa of Sale between MscaUoy Corporation, Seller, and Ashley II of Chariestoo, LLC, Purchaser)

#2003-0186 \-Ur,KA\ Id COUIVfBIA aqW4tsa23vl 11 COUArfBlA 7C93}v1 % 0 585P6306 FILED

RECORDER'S PAGE May 31, 2006 NOTE: This page MUST remain 3:19:44 PM with the original document 0 585PG298

Filed By: Charlie Lybraiid, Register Young Clement Rivers, LLP • "' Charleston County, SC

P.O. Box 993 DESCRIPTION AMOUNT Charleston SC 29402 DEC/COV/REST $ 14.00

Postage

TOTAL $ 14.00

DRAWER: B - ECP

DO NOT STAMP BELOW THIS LINE

843-958-4800 101 MEETING STREET CHARLESTON, SC 29401 www.charlestoncounty.org 6B.Wednesday, November 18, 2009_ . P0STANDC0URIER.COM

»'«iiwij»jiii»»Mg.«v JT' •^•v.'VJrvmiKvmm UMmi. rfqwiwmj

U. S. EiivDironmeiniliall Protection Agency, Region 4 Announces a Five-Year Review for the Macalloy Corporation Superfund Site in North Charleston, Charleston County, SC

The U.S. Environmental Protection Agency (EPA) and the South Carolina Department of Health and Environmental Control (SCDHEC) is conducting a Five-Year Review of the rem­ edy for the Macalloy Corporation Superfund Site (the Site) in North Charleston, SC. The jDurpose of the Five-Year Review is to evaluate the protectiveness of cleanup actions taken at the Site.

Background: Macalloy Corporation is a 125-acre parcel located at 1800 Pittsburgh Avenue, North Charleston, SC 29405. The facility manufactured ferrochromium alloy from 1941 to 1998 by smelting chromite ore, coke, silica gravel and bauxite in submerged elec­ tric arc furnaces. Ferrochrornium alloy was used in the production of high quality stainless i steel. The Site was placed on the National Priorities List in February 2000 for environmen­ tal assessment and remediation under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). EPA issued the Record of Decision (ROD) for the Site in August 2002. Clean up work started at the Site in October 2004, pursuant to the terms of a Consent Decree between EPA, Macalloy, and British Oxygen Corporation. ' Construction was completed at the Site in September 2006.

Storm water monitoring was. conducted monthly until July 2008, when data indicated per­ formance standards where achieved. Monitoring c^ontinues for groundwater, sediment qual­ ity, and sand cap thickness in the restored tidal creek. Approximately 20 acres of the Site have been redeveloped as an industrial park. Planning for future beneficial use of the remaining Site area Is undenvay.

Five-Year Review Schedule: The National Contingency Plan requires that remedial actions that result in any hazardous substances, pollutants, or contaminants remaining at the Site above levels that allow for unlimited use and unrestricted exposure be reviewed every five years to ensure protection of human health and the environment. The first Five- Year Review for this Site is anticipated to be completed by February 2010.

i." EPA Invites community participation In the Five-Year Review process.

EPA is conducting this Five-Year Review to evaluate the effectiveness of the remedy and ensure that the remedy remains protective of human health and the environment. As part of the Five-Year Review process, the EPA is available to answer any questions about the Site. Community members who have questions about the Site, the Five-Year Review process, or who would like to participate in a community interview, are asked to contact the following:

Craig Zeller Sherryl A. Carbonaro Remedial Project Manager Community Involvement Coordinator (404) 562-8227 (800) 564-7577 zeller.craig @ epa.gov [email protected]

Mailing Address: U. S. EPA, 61 Forsyth St., S.W., Atlanta, GA 30303-8960

For more Information on the Macalloy Site, please visit:

The EPA web page at www.epa.gov/reqion4/waste/npl/nplsc/macalosc or The Site Administrative Record at The Charleston Main Library; 68 Calhoun Street, Charleston, SC 29401. I———w^^w^—^^lMiroiTW f.iim-»iiwnmll..ljw.ij»ll nil

Groundwater

First Quarter Lorig-Term Groundv\/ater Monitoring Report; Macalloy Corporation Site, Charleston, South Carolina , EnSafe, January 17, 2007

Event 2 Long-Term Groundwater Monitoring Report; Macalloy Corporation Site, Charleston, South Carolina, EnSafe, March 27, 2007

Event 3 Long-Term Groundwater Monitoring Report; Macalloy Corporation Site, Charleston, South Carolina, EnSafe, June 28, 2007

Long-Term Groundwater Monitoring Report Event 4, Macalloy Corporation Site, Charleston, South Carolina, EnSafe, September 2007

Long-Term Groundwater Monitoring Report Event 5, Macalloy Corporation Site, Charleston, South Carolina, EnSafe, December 21, 2007

Optimized Remedial Groundwater Program Technical Memorandum, Macalloy Corporation NPL Site, Charleston, South Carolina, EnSafe, January 8, 2008

Long-Term Groundwater Monitoring Report Interim Event 5A Macalloy Corporation Site, Charleston, South Carolina, EnSafe, March 4, 2008

Long-Term Groundwater Monitoring Report Event 6, Macalloy Corporation Site, Charleston, South Carolina, EnSafe, May 15, 2008

Delineation of Potential Plume in the Vicinity of MW060 Technical Memorandum, Optimized Remedial Groundwater Program, Macalloy Corporation NPL Site, Charleston, South Carolina, EnSafe, June 20, 2008

Supplemental Groundwater Treatment at MW041, MW047, MW060 and MW061 Technical Memorandum, Macalloy Corporation NPL Site, Charleston, South Carolina, EnSafe, September 29, 2008

001 Tidal Creek- Work Plan to Repair Cap Near Transect 3 Technical Memorandum, Macalloy Corporation NPL Site, EnSafe, December 1, 2008

001 Tidal Creek Cap Repair Completion Report Technical Memorandum, Macalloy Corporation NPL Site, EnSafe, February 9, 2009

Supplemental Groundwater Treatment Completion Report, Macalloy Corporation NPL Site, EnSafe, February 9, 2009 • Long-Term Groundwater Monitoring Report - Event 7 Macalloy Corporation Site, Charleston, South Carolina, EnSafe, March 18, 2009

• Long-Term Groundwater Monitoring Report Event 8, Macalloy Corporation Site, Charleston, South Carolina, EnSafe, August 24, 2009

• EnSafe, (2007, November). Long-Term Groundwater Monitoring Report Event 9, Macalloy Corporation Site, Charleston, South Carolina, EnSafe, November 23, 2009.

Tidal Marsh

• Year 2 Marsh Restoration Monitoring, Macalloy Corporation Site, Charleston, South Carolina, EnSafe, July 27, 2007

• Year 3 Marsh Restoration Monitoring, Macalloy Corporation Site, Charleston, South Carolina, EnSafe, July 30, 2008

Zone A 001 Tidal Creek

• Tidal Creek Year 1 Annual Cap Monitoring Report, Macalloy Corporation Site, Charleston, EnSafe, June 29, 2006

• Year 2 Tidal Creek Cap Monitoring Report, Macalloy Corporation Site, Charleston, South Carolina , EnSafe, July 27, 2007

• Year 3 Tidal Creek Cap Monitoring Report, Macalloy Corporation Site, Charleston, South Carolina , EnSafe, June 30, 2008

• Year 4 Tidal Creek Cap Monitoring Report, Macalloy Corporation Site, Charleston, South Carolina, EnSafe, September 10, 2009

Zone C sediment

• Zone C Sediment Post-Construction Monitoring Report (Event 1); Macalloy Corporation Site, Charleston, South Carolina, EnSafe, December 8, 2006

• Zone C Sediment Post-Construction Monitoring Report (Event 2); Macalloy Corporation Site, Charleston, South Carolina, EnSafe, February 10, 2009

• Zone C Sediment Post-Construction Monitoring Report (Event 3); Macalloy Corporation Site, Charleston, South Carolina, EnSafe, December 8, 2009 Appendix E Photographs of Tidal Marsh before and after Restoration Macalloy Corporation NPL Site Tidal Marsh Restoration Charleston, South Carolina

Photo 1: Disturbed Tidal Marsh immediately after planting- March 2005 ^:yE£5ij4

2: Restored Tidal Marsh and Undisturbed Tidal iVIarsh- 5 Years after Restoration Appendix F Five Year Review Site Inspection Checklist Five-Year Review Site Inspection Checklist

I. SITE INFORMATION Site name: Macalloy Corporation NPL Site Date of inspection: 10/16/2009 Location and Region: Charleston. SC; US EPA EPA ID: SCD003360476 Region 4 Agency, office, or company leading the five-year Weather/temperature: review: US EPA Region 4 Cloudy, 60° F Remedy Includes: (Check all that apply) OLandfiil cover/containment OMonitored natural attenuation dlAccess controls [IlGroundwater containment IXI Institutional controls CUVertical barrier walls OGroundwater pump and treatment nSurface water collection and treatment KlOther: • Groundwater: Enhanced In-situ Chemical Reduction

• Sediment: E.xcavation. Upland Disposal, Capping and Restoration

• Soil: On-site Chemical Reduction

• Radiological Material: E.xcavation and Off-site Disposal

• Surface Water/ Storm Water: Comprehensive Storm Water Management System Attachments: ^ Inspection team roster attached ^ Site map attached

II. INTERVIEWS (Check all that apply) O&M site manager Chad H. Tripp Project Manager, EnSafe Inc. 10/16/2009 Name Title Date Interviewed ^ at site HHat office \Z\ by phone Phone no. Problems, suggestions: Q Report attached None suggested

2. O&M staff Name Title Date InteiA'iewed ^ at site \Z\ at office dj by phone Phone no. Problems, suggestions: CH Report attached none

[Type text] OSU-El^ i\o. 9355.7-03B-I'

Local regulatory authorities and response agencies (i.e., State and Tribal offices, emergency response office, police department, office of public health or environmental health, zoning office, recorder of deeds, or other city and county offices, etc.) Fill in all that apply.

Agency : South Carolina Department Health and Environmental Control (SC DHEC) Contact: Greg Cassidy Environmental Engineer 10/16/09 Name Title Date Phone no. Problems; suggestions; CH Report attached None suggested

Agency SC DHEC Contact Chuck Williams Geolotiist 10/16/09 Name Title Date Phone no. Problems; suggestions; EH Report attached None suggested

Agency United States Environmental Protection Agency (US EPA) Contact Craig Zeller Remedial Project Manager 10/16/09 Name Title Date Phone no. Problems; suggestions; CH Report attached None suggested

Agency Contact Name Title Date Phone no. Problems; suggestions; EH Report attached

Other interviews (optional) EH Report attached. Tim Nelson, Project Coordinator, Macalloy PRP Group, 10/16/09 Paul Meierer, Vice President. Macalloy. 10/16/09 Gerald Pouncey, Attorney representing Shipyard Creek Associates, MMM Law, 10/16/09 (imER No. 935?. 7-II3B-P

III. ON-SITE DOCUMENTS & RECORDS VERIFIED (Check all that apply) 1. O&M Documents M O&M manual Kl Readily available M Up to date D N/A ^As-built drawings Kl Readily available KlUp to date D N/A ^ Maintenance logs ^ Readily available ^Up to date D N/A Remarks

2. Site-Specific Health and Safety Plan lElReadily available ^ Up to date DN/A EHContingency plan/emergency response plan EH Readily available EH Up to date KlN/A Remarks

^>. O&M and OSHA Training Records lElReadily available Kl Up to date DN/A Remarks

4. Permits and Service Agreements EH Air discharge permit EH Readily available EH Up to date ^ N/A n Effluent discharge D Readily available EH Up to date M N/A D Waste disposal. POTW Q Readily available D Up to date g] N/A EHOther permits: SC DHEC Groundwater Injection Permit (PRBs) KlReadily available Kl Up to date DN/A Remarks

5. Gas Generation Records EH Readily available EH Up to date IEIN/A Remarks

6. Settlement Monument Records EH Readily available EH Up to date K|N/A Remarks

7. Groundwater Monitoring Records ^ Readily available ^ Up to date DN/A Remarks

8. Leachate Extraction Records EH Readily available EH Up to date KlN/A Remarks

9. Discharge Compliance Records DAir D Readily available D Up to date ^ N/A n Water (effluent) D Readily available G Up to date M N/A Remarks

10. Daily Access/Security Logs EH Readily available EH Up to date ^ N/A Remarks:

[Type text] OSIVER No. 9355.7-03B-P

IV. O&M COSTS 1. O&M Organization EH State in-house EH Contractor for State n PRP in-house M Contractor for PRP I I Federal Facility in-house EH Contractor for Federal Facility D Other

O&M Cost Records M Readily available Kl Up to date I I Funding mechanism/agreement in place Original O&M cost estimate $ 194,200 EH Breakdown attached

Total annual cost by year for review period if available

From_ 2006_ To 2007 $33,500 EH Breakdown attached Date Date Total cost

From 2007 _To_ 2008 $87,800 EH Breakdown attached Date Date Total cost

From 2008 _To_ 2009 $219,800 EH Breakdown attached Date Date Total cost

From 2009 _To_ 2010 $42,500 n Breakdown attached Date Date Total cost

Unanticipated or Unusually High O&M Costs During Review Period Describe costs and reasons: Unanticipated costs included: 2008 Groundwater monitoring program optimization= $6,300 2008 Installation and sampling of MW060, MW06I. and MW062= $16,770 2008 Delineation of residual chromium with DPT assessment= $15,000 2008 Repair of 001 Tidal Creek Cap= $2,700 (EnSafe) + $3,500 (Entact) 2008 Supplemental Groundwater Treatment planning, implementation, and completion report: $20,300 (Ensafe) + $116.690 (Entact) 2008 Additional Storm water monitoring: $8,140

V. ACCESS AND INSTITUTIONAL CONTROLS lEl Applicable D N/A A. Fencing 1. Fencing damaged EH Location shown on site map EH Gates secured N/A Remarks

B. Other Access Restrictions OSHER No. 9355.7-03B-P Signs and other security measures EH Location shown on site map ^N/A Remarks

[Type text] aSlVER No. 9355.7-03B-P

C. Institutional Controls (ICs) Implementation and enforcement Site conditions imply ICs not properly implemented EH Yes ^ No EH N/A Site conditions imply ICs not being fully enforced EHVes ^No I I N/A

Type of monitoring {e.g., self-reporting, drive by) Frequency Responsible party/agency Contact Name Title Date Phone no.

Reporting is up-to-date EH Yes EH No EH N/A Reports are verified by the lead agency EH Yes EH No EH N/A

Specific requirements in deed or decision documents have been met EH Yes [I] No I I N/A Violations have been reported EH Yes EH No I I N/A Other problems or suggestions; \Z\ Report attached

Adequacy ^ ICs are adequate EH ICs are inadequate EH N/A Remarks

D. General Vandalism/trespassing ^ Location shown on site map EH No vandalism evident Remarks: Site has no security fencing or aates.

Land use changes on site ^ N/A Remarks Landuse is still commercial and industrial

Land use changes off site ^ N/A Remarks no changes

VI. GENERAL SITE CONDITIONS A. Roads D Applicable Kl N/A Roads damaged EH Location shown on site map EH Roads adequate \Z\ N/A Remarks OSIVER No. 9355.7-03B-P

B. Oth er Site Conditions Remarks

VII. LANDFILL COVERS D Applicable ^N/A

A. Lai dfill Surface

1. Settlement (Low spots) EH Location shown on site map [Z\ Settlement not evident .Areal extent Depth Remarks

2. Cracks [m Location shown on site map EH Cracking not evident Lengths Widths_ Depths Remarks

1 Erosion EH Location shown on site map EH Erosion not evident Areal extent Depth Remarks

4. Holes EH Location shown on site map EH Holes not evident Areal extent Depth Remarks

5. N'egetative Cover EH Grass EH Cover properly established EH No signs of stress EH Trees/Shrubs (indicate size and locations on a diagram) Remarks

6. Alternative Cover (armored rock. , concrete, etc.) EH N/A Remarks

7. Bulges EH Location shown on site map EH Bulges not evident Areal extent Height Remarks

[Type text] OSH'ER No. 9355.7-03B-P

Wet AreasAVater Damage EH Wet areas/water damage not evident I I Wet areas EH Location shown on site map Areal extent_ I I Ponding EH Location shown on site map Areal extent_ I I Seeps EH Location shown on site map Areal extent_ I I Soft subgrade EH Location shown on site map Areal e\tent_ Remarks

9. Slope Instability EH Slides EH Location shown on site map EH No evidence of slope instability Areal extent Remarks

B. Benches Q Applicable D N/A (Horizontally constructed mounds of earth placed across a steep landfill side slope to interrupt the slope in order to slow down the velocity of surface runoff and intercept and convey the runoff to a lined channel.)

1. Flows Bypass Bench EH Location shown on site map EH N/A or okay Remarks

2. Bench Breached EHUocation shown on site map EH N/A or okay Remarks

3. Bench Overtopped EH Location shown on site map EH N/A or okay Remarks

C. Letdown Channels EH Applicable • N/A (Channel lined with erosion control mats, riprap, grout bags, or gabions that descend down the steep side slope of the cover and will allow the runoff water collected by the benches to move off of the landfill cover without creating erosion gullies.)

1. Settlement [^ Location shown on site map EH No evidence of settlement Areal extent Depth Remarks

2. Material Degradation EH Location shown on site map I I No evidence of degradation Material type Areal extent Remarks

3. Erosion EH Location shown on site map Q No evidence of erosion Areal extent Depth Remarks OSWER No. 9355.7-03B-P

4. Undercutting EH Location shown on site map I I No evidence of undercutting Areal extent Depth Remarks

5. Obstructions Type I I No obstructions I I Location shown on site map Areal extent Size_ Remarks

E.xcessive Vegetative Growth Type I I No evidence of excessive growth I I Vegetation in channels does not obstruct flow I I Location shown on site map Areal extent_ Remarks

D. Cover Penetrations EH Applicable EH N/A 1. Gas Vents EH Active I I Passive I I Properly secured/locked EH Functioning EH Routinely sampled EH Good condition I I Evidence of leakage at penetration EH Needs Maintenance DN/A Remarks

2. Gas Monitoring Probes I I Properly secured/locked \Z\ Functioning EH Routinely sampled EH Good condition [I] Evidence of leakage at penetration EH Needs Maintenance I I N/A Remark s

3. Monitoring Wells (within surface area of landfill) EH Properly secured/locked EH Functioning EH Routinely sampled EH Good condition I I Evidence of leakage at penetration EH Needs Maintenance EH N/A Remarks

4. Leachate Extraction Wells I I Properly secured/locked EH Functioning \Z] Routinely sampled EH Good condition EH Evidence of leakage at penetration EH Needs Maintenance I I N/A Remarks

5. Settlement Monuments EH Located EH Routinely surveyed EH N/A Remarks

[Type text] OSIVER No. 9355.7-03B-P

E. Gas Collection and Treatment \Z\ Applicable DN/A

1. Gas Treatment Facilities EH Flaring EH Thermal destruction EH Collection for reuse EH Good condition EH Needs Maintenance Remarks

2. Gas Collection Wells, Manifolds and Piping EH Good condition EH Needs Maintenance Remarks

3. Gas Monitoring Facilities (e.g., gas monitoring of adjacent homes or buildings) EH Good condition EH Needs Maintenance EH N/A Remarks

F. Cover Drainage Layer EH Applicable DN/A

1. Outlet Pipes Inspected D Functioning DN/A Remarks

~i Outlet Rock Inspected EH Functioning • N/A Remarks

G. Detention/Sedimentation Ponds \Z\ Applicable QN/A

1. Siltation Areal extent Depth EH N/A EH Siltation not evident Remarks

2 Erosion Areal extent Depth \Z\ Erosion not evident Remarks

3. Outlet Works • Functioning D N/A Remarks

4. Dam EH Functioning EH N/.A Remarks OSIVER No. 9355.7-03B-P

H. Retaining Walls D Applicable D N/A

1. Deformations EH Location shown on site map EH Deformation not evident Horizontal displacement Vertical displacement Rotational displacement Remarks

2. Degradation EH Location shown on site map EH Degradation not evident Remarks

1. Perimeter Ditches/Off-Site Discharge D Applicable Q N/A

1. Siltation EH Location shown on site map [Z\ Siltation not evident Areal extent Depth Remarks

2. Vegetative Growth EH Location shown on site map EH N/A G Vegetation does not impede flow Areal extent Type Remarks

j>. Erosion EH Location shown on site map EH Erosion not evident Areal extent Depth Remarks

4. Discharge Structure EH Functioning EH N/A Remarks

VIII. VERTICAL BARRIER WALLS D Applicable Kl N/A

1. Settlement EH Location shown on site map EH Settlement not evident Areal extent Depth Remarks

1 Performance MonitoringType of monitoring EH Performance not monitored Frequency EH Evidence of breaching Head differential Remarks

[Type text] OSIVER No. 9355.7-03B-P

I\. GROUNDW.ATER/SURFACE WATER REMEDIES Kl Applicable D N/A A. Groundwater Extraction Wells, Pumps, and Pipelines EH Applicable M N/A I. Pumps, Wellhead Plumbing, and Electrical I I Good condition EH All required wells properly operating EHNeeds Maintenance ^ N/A Remarks

2. Extraction System Pipelines, Valves, Valve Boxes, and Other .Appurtenances I I Good condition EH Needs Maintenance Remark s

3. Spare Parts and Equipment EH Readily available EH Good condition EH Requires upgrade EH Needs to be provided Remarks

B. Surface Water Collection Structures, Pumps, and Pipelines EH Applicable ^N/A 1. Collection Structures, Pumps, and Electrical I I Good condition EH Needs Maintenance Remarks

2. Surface Water Collection System Pipelines, Valves, Valve Boxes, and Other Appuitenances I I Good condition EH Needs Maintenance Remarks

3. Spare Parts and Equipment I I Readily available C] Good condition EH Requires upgrade EH Needs to be provided Remarks OSIVER No. 9355.7-03B-P

C. Treatment System ^Applicable EH N/A

I. Treatment Train (Check components that apply) I I Metals removal EH Oil/water separation EH Bioremediation EH Air stripping EH Carbon adsorbers n Filtei-s„ I I Additive (e.g., chelation agent, flocculent)_

^ Others; Enhanced In-Situ Chemical Reduction/Penneable Reactive Baniers (PRBs) M Surface soil is in good condition and stable

I I Needs Maintenance I I Sampling ports properly marked and functional I I Sampling/maintenance log displayed and up to date I I Equipment properly identified I I Quantity of groundwater treated annually I I Quantity of surface water treated annually

Electrical Enclosures and Panels (properly rated and functional) ^ N/A EH Good condition EH Needs Maintenance Remarks

Tanks, Vaults, Storage Vessels ^ N/A EH Good condition EH Proper secondary containment I I Needs Maintenance Remarks

Discharge Structure and Appurtenances M N/A EH Good condition EH Needs Maintenance Remarks

5. Treatment Building(s) ^ N/A EH Good condition (esp. roof and doorways) EH Needs repair EHChemicals and equipment properly stored Remarks

6. Monitoring Wells (Long Term Effectiveness) ^Properly secured/locked ^ Functioning ^ Routinely sampled ^ Good condition I I All required wells located EH Needs Maintenance EH N/A

Remarks: The following wells need maintenance: i) MW054R is covered by compacted road fill and needs to be located, surveyed and improved if necessai^y. ii) MW056. MW057R. and MW058 need a horizontal and vertical location survey.

[Type text] OSIVER No. 9355.7-03B-P

D. Monitoring Data 1. Monitoring Data ^ Is routinely submitted on time M Is of acceptable qua ity 2 Monitoring data suggests: ^ Groundwater plume is effective -ly contained ^ Contaminant concentrations are declining

D. Monitored Natural Attenuation N/A Monitoring Wells (natural attenuation remedy) I I Properly secured/locked EH Functioning [U Routinely sampled I I Good condition I I All required wells located EH Needs Maintenance EH N/A Remarks

.\. OTHER REMEDIES If there are remedies applied at the site which are not covered above, attach an inspection sheet describing the physical nature and condition of any facility associated with the remedy. An example would be soil vapor extraction.

001 Tidal Creek Sediment: Excavation, Upland Disposal, Capping and Restoration • Cap Condition Assessment: Good condition based on recent cap thickness measurements.

Soil: On-site Chemical Reduction • Condition Assessment: Stable surface condition in vicinity of soil remediation.

Radiological Material: Excavation and Off-site Disposal • Condition Assessment: Stable surface condition in vicinity of radiological material excavation.

Surface Water/ Storm Water: Comprehensive Storm Water Management System • Condition Assessment: Functioning; however, vegetation growth may obscure evaluation of potential sediment buildup. OSIVER No. 9355.7-03B-P

XI. OVERALL OBSERVATIONS A. Implementation of the Remedy

Describe issues and observations related to the implementation and scope of O&M procedures. In particular, discuss their relationship to the current and long-term protectiveness of the remedy.

The following issues were discussed during the five year review site inspection:

Zone A 001 Tidal Creek Cap: One small section of the sand cap was repaired and an increasing number of transects with thicknesses less than 18 inches have been observed each year. O&M was recommended during the second five-year period to monitor and maintain the protectiveness of the remedy.

Tidal Marsh Plant Surveys: Stem density surveys of the hand-planted grass in the disturbed tidal marsh were effective in evaluating the status of restoration. OCRM success criteria for plant restoration have been met; therefore, no future monitoring is recommended. Surveys complete.

Zone C Sediment Monitoring: During the five-year review period, concentrations of total metals in October 2009 were below protective ranges established by the FRAR and toxicity tests resulted in no adverse effects to benthic organisms; therefore, no additional monitoring is recommended for Zone C. Monitoring Complete.

Groundwater- Monitoring Optimization: During the October 2009 First Five-Year Site Inspection, SCDHEC and EPA recommended groundwater monitoring to continue semi-annually for the next two years and then annually for the following three years until the second five-year review.

Groundwater- MW054R: Elevated concentrations of total chromium above the groundwater cleanup goal were reported at MW054R, during Event 8 in April 2009. This well could not be re-sampled, nor concentrations verified during Event 9 sampling in October 2009 as the well was obstructed with road fill. MW054R is located on property owned by Paper Stock. This property contains deed restrictions that require Paper Stock lo be respectful of the remediation system.

Groundwater- Well Sun'evs: A horizontal and vertical professional coordinate sur\'ey has not been performed for wells MW054R, MW056, MW057R, and MW058. This data is needed to adequately determine groundwater elevations and flow direction on the site.

Surface Water/ Storm Water Management System: During the site inspection, it was noted that vegetation in the storm water ponds and ditches were overgrown, obscuring the evaluation of sediment buildup.

[Type text] OSIVER No. 9355.7-II3B-P

Early Indicators of Potential Remedy Problems Describe issues and observations such as unexpected changes in the cost or scope of O&M or a high frequency of unscheduled repairs that suggest that the protectiveness of the remedy may be compromised in the future.

Of the issues discussed during the five year review site inspection, and noted in Section A above, the following was an unexpected issue, and is i-ecommended to assess the future protectiveness of the remedy:

Groundwater- MW054R: Elevated concentrations of total chromium above the groundwater cleanup goal were reported at MW054R, during Event 8 in April 2009. This well could not be re-sampled, nor concentrations verified during Event 9 sampling in October 2009 as the well was obstructed with road fill. MW054R is located on property owned by Paper Stock. This property contains deed restrictions that require Paper Stock to be respectful of the i-emediation system. O.S/f£/? No. 9355.7-03B-P

C. Opportunities for Optimization

Describe possible opportunities for optimization in monitoring tasks or the operation of the remedy.

Of the issues discussed during the five year review site inspection, and noted in Section A above, the following are recommended to optimize monitoring of the remedy:

Zone A 001 Tidal Creek Cap: Monitor cap thickness in 2011 and 2013

Tidal Marsh Plant Surveys: Completed/ Discontinue

Zone C Sediment Monitoring: Completed/ Discontinue

Groundwater- Monitoring Optimization: Continue long term effectiveness groundwater monitoring on semi-annual basis for next two years and then annually thereafter, depending on results. Monitoring wells MW049, MW050, MW051 and MW059 will be dropped from the long-term monitoring network, but will not be abandoned at this time in case additional samples are required in the future. The following 17 monitoring wells are recommended for the sampling network: MW040 to MW048, MW052, MW054R, M\V055. MW056. MW057R. MW060. MW061, and MW062.

Groundwater- Well Surveys: Attain a horizontal and vertical professional coordinate survey of MW054R, MW056. MW057R, and MW058.

Surface Water/ Storm Water Management System: Evaluate vegetation and sediment buildup in the stomi water management system and clean if necessary.

[Type text] OSWER No. 9355.7-03B-P

SITE INSPECTION ATTENDANCE The following is a list of individual interviewed for this five-year review. See the attached contact record(s) for a detailed summary of the interviews.

ChUit^ PH ChS^fit 10/1 m Name Title/Position Organization ^Date

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£PA /6- /G-0^ Name Title/Position Organization Date

fM /o -A-o7 Name Title/Position Organization Date

PAUL \A^AUJ&X- V^'P (c K/^-c"? Name Title/Position Organization Date >v^ 'hi ^ bo 4 -^o l^cA favd

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A-l Appendix G Photographs of Site during Site Inspection Macalloy Corporation NPL Site October 16, 2009 Site Inspection Charleston, South Carolina

Photo 1: Southern portion of Site facing west

Photo 2: Middle portion of Site facing west Macalloy Corporation NPL Site October 16, 2009 Site Inspection Charleston, South Carolina

Photo 3: South east portion of Site facing northwest Macalloy Corporation NPL Site October 16, 2009 Site Inspection Charleston, South Carolina

Photo 4: Outfall in Shipyard Creek facing east

Photo 5: Eastern Storm Water Pond facing southwest Macalloy Corporation NPL Site October 16, 2009 Site Inspection Charleston, South Carolina

Photo 7: 001 Tidal Creek and Tidal Marsh facing east

Photo 8: 001 Tidal Creek and Restored Tidal Marsh Macalloy Corporation NPL Site October 16, 2009 Site Inspection Charleston, South Carolina

Photo 9: Restored Tidal Marsh and Undisturbed Tidal Marsh

Photo 10: MW047 facing southwest Macalloy Corporation NPL Site October 16, 2009 Site Inspection Charleston, South Carolina

Photo 11: Northern Storm Water Pond facing north

Photo 12: Northern Storm Water Pond facing west Macalloy Corporation NPL Site October 16, 2009 Site Inspection Charleston, South Carolina

Photo 13: Far north corner of Site facing south

Photo 14: Eastern drainage ditch facing north Macalloy Corporation NPL Site October 16, 2009 Site Inspection Charleston, South Carolina

Photo IS: Corner of Pittsburgh A ve and Sewanee Rd facing west

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Photo 16: Commercial business on corner of Sewanee Rd and Tellico Rd Macalloy Corporation NPL Site October 16, 2009 Site Inspection Charleston, South Carolina

Photo 17: Sewanee Rd facing west