•

Fourth Five-Year Review Report

For Carolawn Superfund Site

Chester County, Fort Lawn, South Carolina

September 2013

• Prepared by:

U.S. Environmental Protection Agency - Region 4 Atlanta, Georgia

and

South Carolina Department of Health and Environmental Control Columbia, South Carolina ..

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Date: ~~~A~:~b~~ •

Director, Superfund Division

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Table of Contents.................................................................................. 3

List of Acronyms and Abbreviations............................................................. 5

Executive Summary ................. ~............................................................ 8

Five-Year Review Summary Form·:............................................................ 11

Section 1. Introduction........................................................................ 15

Section 2. Site Chronology.................................................................... 16

Section 3. Background.......... .-............................................................. 16

3.1 Physical Charact~ristics... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

3.2 Land and Resource Use...................................................... 17

3.3 History of Contamination.................................................... 18

3.4 Initial Response Action...................................................... 18

3.5 Basis for Taking Action . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . .. . ......... 19

Section 4. Remedial Actions ...·..- ......................................................... .

23

22

4.1 Remedy Selection ......................................................... .

4.1.1 Remedial Action Objectives for the OU-1 ........................... . 23

4.1.2 Components of the Selected Remedy-OU-1 ......................... . 23

4.2 Remedy Implementation (OU-1) ...................................... . 25

254.2.1 Migration Con~rol ....................................................... .

294.2.2 Source Control (OU-2) .................................................. .

4.3 GWETS Operation, Maintenance and Monitoring Costs .............. .

Section 5. Progress Since the Last Five-Year Review ................................ . 32

5.1 Modify the 1989 ROD to include Vinyl Chloride as a performance

measure......................................................................... 32·•

5.2 Determine the appropriate ICs for the Site . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

5.3 Evaluate available groundwater treatment technologies to restore

the contaminated aquifer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... 33

5.4 Place a deed notice acknowledging the potential risk, if any of soil

vapor migration '.:......................................................... ... 33

...,

.)

Section 6. Five-Year Review Process........................................................... 33

6.1 Administrative Component................................................ 33

6.2 Community Involvement.................................................. 34

6.3 Document Review........................................................ 34

6.4 Data Review............................................................... 36

6.4.1 Results of the GWETS Evaluation and EISB Pilot Study.......... 36

6.4.2 Status of the Soil Vapor Extraction Pilot Study..................... 36

6.4.3 Post-GWETS Shutdown VOC Concentrations/Plume Conditions 38

6.4.4 Vapor Intrusion Pathway Evaluation................................. 38

6.5 Site Inspection.................................................................... 39

6.6 Site Interviews ............................................................ .

Section 7. Technical Assessment........................................................... 40

7.1 Question A: Is the Remedy Functioning as Intended by Decision

Docu1nent? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

7.2 Question B: Are the Exposure Assumptions, Toxicity Data,

Cleanup Levels, and Remedial Action Objectives (RAOs) used at

the Time Still Valid? ............... :..................................... 41

7.3 Question C: Has Any Other Information Come to Light that

Could Call into Question the Protectiveness of the Remedy? ....... .. 42

7.4 Technical Assessment Summary....................................... 42

Section 8. Issues.................................................................................. 43

Section 9. Recommendations and Follow-up Actions..................................... 44

Section 10. Protectiveness Statement......................................................... 45

Section 11. Next Review....................................................................... 45

Appendices: A. List of Documents Reviewed B. Community Relations C. Tables 1 through 9 D. Figures 1 through 8 E. Site Inspection Check Form, Interview Documentation Form and

Photographs

4

1989 ROD

1995 ROD

7Q10

AOC

ARAR

AWQC

BGS

BNA

BRA

CAG

CERCLA

CFR

coc cocc COPC

COP EC

CRA

csc EISB

EPA

ESD

EW

FFS

FT

FYR

GAC

GWETS

HQ

List of Acronyms and Abbreviations

Record of Decision for Operable Unit 1 (OU-1)

Record of Decision for Operable Unit 2 (OU-2)

Lowest 7-day average flow that occurs (on average) once every 10 years

Administrative Order on by Consent

Applicable or Relevant and Appropriate Requirement

Ambient Water Quality Criteria

Below Ground Surface

Base Neutral/Acid Extractables

Baseline Risk Assessment

Community Advisory Group

Comprehensive Environmental Response, Compensation, and Liability Act

Code of Federal Regulations

Contaminants of Concern

Columbia Organic Chemical Company

Contaminants of Potential Concern

Contaminant of Potential Ecological Concern

Conestoga-Rovers & Associates

Carolawn Steering Committee

Enhanced In-Situ Biodegradation

United States Environmental Protection Agency

Explanation of Significant Differences

Extraction Well

Focused Feasibility Study

Feet

Five-Year Review

Granular Activated Carbon

Groundwater Extraction and Treatment System

Hazard Quotient

5

List of Acronyms and Abbreviations (con't)

HQ

I Cs

IRM

LFG

LHA

LOAEL

MCL

MG/KG

MSD

MSDS

MSL

MW

NAAQS

NCP

ND

NOAEL

NPDES

NPL

OB&G

O&M

OM&M

OSWER

OU

PCBs

PM10

PRG

PRP

Hazard Quotient

Institutional Controls

Interim Remedial Measure

Landfill Gas

Lifetime Health Advisory

Observed Adverse Effects

Maximum Contaminant Level

Milligrams per Kilograms

Metropolitan Sanitary District

Material Safety Data Sheet

Mean Sea Level

Monitoring Well

National Ambient Air Quality Standards

National Contingency Plan

Non-Detect

No Observed Adverse Effects

National Pollution Discharge Elimination System

National Priorities List

O'Brien & Gere

Operation and Maintenance

Operation, Maintenance and Monitoring

Office of Solid Waste and Emergency Response

Operable Unit

Polychlorinated Biphenyls

Particulate Matter (Particles are 10 micrometers or less)

Preliminary Remediation Goals

Potentially Responsible Party

6

PRP

PV

QC

RA

RAGS

RAO

RD

RI/FS

ROD

RPM

RW

SOWA

SCDHEC

SEPCO

SVE

svoc UAO

TAL

TBC

TCL

TSS

UG/KG

UG/L

USDW

voe

List of Acironyms and Abbrevaations (con'O

Potentially Responsible Party

Pore Volume

Quality Control

Remedial Action

Risk Assessment Guidance for Superfund

Remedial Action Objective

Remedial Design

Remedial Investigation/Feasibility Study

Record of Decision

Remedial Project Manager

Recovery Well

Safe Drinking Water Act

South Carolina Department of Health and Environmental Control

Southeastern Pollution Control Company

Soil Vapor Extraction

Semi-volati'le Organic Compound

Unilateral Administrative Order

Target Analyte List

Ta-Be-Considered

Target Compound List

Total Suspended Solids

Micrograms per Kilograms

Micrograms per Liter

Underground Source of Drinking Water

Vapor Intrusion

Volatile Organic Compound

7

VI

!Execu.ntive Summary

The Carolawn Superfund Site (the Site) is located in Fort Lawn, Chester County, South Carolina. The Site consists of two Operable Units (OUs). OU-1 is a 3-acre area completely enclosed by a chain link fence and the areal extent of all groundwater contamination beneath the Site. OU-2 is an undeveloped woodland area located beyond the fenced area of OU-1. OU-2 includes the soils, surface water and sediment in Fishing Creek.

Beginning in 1970, the Southeastern Pollution Control Company (SEPCO) used the Site as a storage facility for a solvent recovery plant located in Clover, South Carolina. SEPCO filed bankruptcy in 1974 and abandoned the Site, leaving approximately 2,500 drums of solvent on the Site. In January 1975, as part of the effort to clean up the SEPCO plant in Clover, South Carolina, the Columbia Organic Chemical Company (COCC) transported and stored approximately 2,000 drums at the Site. As payment for services rendered during the cleanup of the plant in Clover, South Carolina, COCC received the Carolawn property. After 1975, the South Carolina Recycling and Disposal, Inc. (SCRDI), a subsidiary of COCC, controlled the Site.

In October 1978, SC RD I was given approval to dispose of empty drums on the fenced area of the property. After the disposal, SC RD I sold the fenced area of the Site to the Caro lawn Company. Between 1978 and 1980, the Carolawn Company conducted waste storage, treatment, and disposal operations within the fenced area. When the Carolawn Company abandoned the Site in 1980, the fenced area contained 2 incinerators, 2 storage trailers, 14 storage tanks, and over 400 drums containing liquid and solid wastes. Over 600 drums and 11 tanks were also located to the north of the fenced area. Groundwater impact by volatile organic compounds (VOCs) resulted from the historical solvent management activities during the 1970s.

During the 1980s, removal activities conducted by the EPA and the Carolawn Steering Committee (CSC) addressed the source of the groundwater contamination by removing drums, waste materials and contaminated soils. The Site was listed on the National Priorities List (NPL) in 1983. The CSC conducted an additional removal action at the Site in 1986, and a multi-phase Remedial Investigation/Feasibility Study (Rl/FS) between 1987 and 1989. These studies identified YOCs in groundwater as the only contaminants of concern (COCs) with the potential to pose unacceptable risk to human health or the environment. In September 1989, the EPA issued a Record of Decision ( 1989 ROD) for OU-1 to further address the groundwater contamination at the Site. The major components of the 1989 ROD included groundwater extraction, on-site treatment of the contaminated groundwater, and discharge of treated groundwater into Fishing Creek. Due to the effectiveness of the removal actions, no source of contamination remains at the Site. However, the remedy for OU-I did require additional investigation in the disposal area north of the fenced area (OU-2) to verify the presence or absence of contamination. In addition, the remedy for OU-1 provided for the implementation of institutional controls (ICs). To address OU-2, the EPA completed a RI in October 1994 and issued a ROD for OU-2 (1995 ROD) for no further action as the final remedy in September 1995. Construction of the groundwater extraction and treatment system (GWETS) for OU-1 was completed by the CSC in June 1996 and operation of the GWETS commenced in October 1996.

Since operation of the G WETS, the EPA completed a Five-Year Review (FYR) in 1998, 2003 and 2008 and implemented two pilot studies to address groundwater contamination at the Site. Although operating as designed, the data collected between 1996 and 2003 indicated the GWETS would not be effective in reducing voe groundwater concentrations to acceptable levels within ten years as described in the 1989 ROD due to site-specific hydraulic challenges. As a result, the EPA recommended a system optimization

8

study to consider the use of alternative remedial technologies to address VOCs in groundwater. In response, the CSC implemented Enhanced In Situ Biodegradation (EISB) treatment of groundwater as a 'pilot study' to accelerate the reduction of VOC concentrations in groundwater. The CSC shutdown the GWETS on July 19, 2004.The shutdown of the GWETS included pump removal and system decommissioning. The pump removal and system decommissioning was conducted in a manner such that the GWETS can be operational within a timely manner, in the unexpected event that resumption of operation is necessary.

The CSC completed EISB injection of a substrate consisting of a soy-oil based product known as Newman Zone in May 2005. 4 years after the GWETS shutdown and EISB implementation, the VOC distribution and plume extent in Site groundwater did not significantly change and the greatest VOC concentration areas remained stable. Based on the remedial progress observed between 2003 and 2008, the third FYR recommended further evaluation of technologies other than the GWETS and EISB to identify a remedy that would more effectively and efficiently restore the contaminated aquifer for future use. In March 2009, the EPA issued a Modified Unilateral Administrative Order (UAO) to the CSC which specified the requirement that a Focused Feasibility Study (FFS) be completed to identify a groundwater remedy more favorable than the GWETS.

In August 2010, the CSC conducted a limited soil vapor extraction (SVE) study to collect data to evaluate the potential use of SVE as an Interim Remedial Measure (IRM) as part of an overall groundwater remediation strategy. The results of the SVE study indicated SVE as a feasible approach to reduce voe mass in the subsurface (vadose zone) which could result in reduced voe concentrations in groundwater. Following discussions with the South Carolina Department of Environmental Health and Control (SCDHEC), the CSC and the Community Advisory Group (CAG), the EPA issued the Notice to Proceed with the remedial design and construction of the SVE system. Construction of the SVE system was completed in January 2012. Operation of the SVE system has reduced VOC mass from the subsurface and is expected to reduce the flux of voes to groundwater which will allow groundwater concentrations to decline over time. Approximately 155 lbs of VOCs have been removed during seventeen months of SVE system operation. In comparison, the GWETS extracted 35 lbs ofVOCs from the groundwater plume during 7 years of operation. SVE system operational data and groundwater plume monitoring suggest voe conditions are improving, source area mass is reducing, and the voe groundwater plume is generally stable and decreasing.VOC mass removal from the SVE system will continue to be monitored to assess the impact of the SVE System on groundwater conditions. This performance data will be used to support completion of the FFS which could lead to modifying the 1989 ROD.

The remedy at the Carolawn Site is protective in the short term since there is no complete exposure pathway to contaminated groundwater and the groundwater extraction and treatment remedy was functioning as intended by the 1989 ROD.

For the remedy to be protective in the long term, the following actions should occur:

" An appropriate decision document should be prepared to add vinyl chloride, 1,2-dichloroethane and tetrachloroethene to the list of cleanup goals to be addressed at this Site.

• Determine the appropriate institutional controls to restrict groundwater use at the Site.

• Evaluate the need for ICs restricting groundwater use on residential properties adjacent to the Site.

9

• Continue to evaluate available groundwater treatment technologies to determine whether such technologies would be more effective than the GWETS in efficiently restoring the contaminated aquifer. If another alternative is preferred, a decision document will be issued for the Carolawn Site.

10

Five-Year Review Summary Form

SITE IDENTIFICATION

Site Name: Carolawn Superfund Site

EPA ID: SCD980558316

NPL Status: Final

Multiple OUs? Has the site achieved construction completion? Yes Yes

REVIEW STATUS

Lead agency: U.S. EPA. Region 4 and the South Carolina Department of Health & Environmental Control (SCDHEC)

Author name: Yvonne Jones and Charles Williams

Author affiliation U.S. EPA, Region 4 and SCDHEC

Review period: March 7, 2013 to August 26, 2013

Date of site inspection: March 7, 2013

Type of review: Statutory

Review number: 4

Triggering action date: 9/25/2008

Due date (five years after triggering action date): 9/24/2013

11

Five-Year Review Summary !Form (continued)

OU(s) wm1out Issues/Recommendations lolen~ified in the Five-Year Review:

OU-2

Issues ano1 Recommendations lo1entifieo1 in the Five-Year Review:

OU(s): 1 Issue Category: Remedy Performance

Issue: The 1989 ROD did not include vinyl chloride, 1,2-dichloroethane and tetrachloroethene in the list of COCs with cleanup goals.

Recommendation: An appropriate decision document should be prepared to add vinyl chloride, 1,2-dichloroethane and tetrachloroethene to the list of cleanup goals to be addressed at this Site.

Affect Current Affect Future Implementing Oversight Milestone Date Protectiveness Protectiveness Party Party

No Yes EPA/State EPA/State 09/30/2016

OU(s): 1 Issue Category: Institutional Controls

Issue: The 1989 ROD required ICs. ICs restricting groundwater use may be necessary because there are no restrictions in place to prevent exposure to contaminated groundwater from the Site that exists above cleanup goals specified in the 1989 ROD, other than SCDHEC's well permit requirements.

Recommendation The EPA, SCDHEC and the CSC should work with the Site Property owners to determine the appropriate ICs at the Carolawn Site to prevent exposure to contaminated groundwater from the Site that exists above cleanup goals specified in the 1989 ROD for execution by a viable property owner willing to execute and record such !Cs.

Affect Current Affect Future Implementing Oversight Milestone Date Protectiveness Protectiveness Party Party

No Yes PRP EPA/State 09/30/2015

OU(s): 1 Issue Category: Institutional Controls

Issue: ICs may be needed on residential properties adjacent to the Site.

Recommendation: Evaluate the need for ICs restricting groundwater use on residential properties adjacent to the Site.

Affect Current Affect Future Implementing Oversight Milestone Date Protectiveness Protectiveness Party Party

No Yes PRP EPA/State 09/30/2015

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five-Yeair lReview SUllmmary !Foirm (confornedl)

OU(s): 1 Issue Category: Remedy Performance

Affect Current Protectiveness

No

Issue: The remedy was functioning as intended by the 1989 ROD. The 1989 ROD estimated 10 years to achieve MCLs. However, it is estimated that the GWETS would have to operate an estimated additional 62 years to achieve MCLs due primarily to the low yield of the bedrock formation.

Recommendation: The EPA should continue to evaluate available groundwater treatment technologies to determine whether such technologies would be more effective than the GWETS in efficiently restoring the contaminated aquifer. If another alternative is preferred, adecision document will be issued for the Carolawn Site.

Affect Future Implementing Oversight Milestone Protectiveness Party Party Date

No PRP EPA/State 12/30/2015

Protectiveness Determination: Addendum Due Date (if applicable): Short-term Protective

Protectiveness Statement:

The remedy at the Carolawn Site is protective in the short term since there is no complete exposure pathway to contaminated groundwater and the groundwater extraction and treatment remedy was functioning as intended by the 1989 ROD.

For the remedy to be protective in the long term, the following actions should occur:

o An appropriate decision document should be prepared to add vinyl chloride, 1,2-dichloroethane and tetrachloroethene to the list of cleanup goals to be addressed at this Site.

o Determine the appropriate institutional controls to restrict groundwater use at the Site.

o Evaluate the need for ICs restricting groundwater use on residential properties adjacent to the Site.

o Continue to evaluate available groundwater treatment technologies to determine whether such technologies would be more effective than the GWETS in efficiently restoring the contaminated aquifer. If another alternative is preferred, a decision document will be issued for the Carolawn Site.

13

IFnve-Year lRevnew Summary lForm (continued)

- Current human exposures at the Site are under control. - Current ground water migration is under control.

D All D Some ~ None The ROD does require institutional controls. Institutional controls restricting groundwater and land use at the Site are needed to ensure that remedial actions at the Site will remain protective of human health and the environment.

14

JFou.nirtlln JFive-Yeair 1Review JRepoirt Cairollawilll §u.npeir1fu.nmll §ite

Jl.G Ilillltirodlu.ndioilll

The purpose of a Five-Year Review (FYR) is to evaluate the implementation and performance of a remedy in order to determine if the remedy will continue to be protective of human health and the environment. The methods, findings, and conclusions of FY Rs are documented in FYR reports. In addition, FYR reports identify issues found during the review, if any, and document recommendations to address them.

The United States Environmental Protection Agency (EPA) prepares FYRs pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Section 121 and the National Contingency Plan (NCP). 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 EPA interpreted this requirement further in the NCP; 40 Code of Federal Regulations (CFR) Section 300.430(t)(4)(ii), which 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 actions no less often than every five years after the initiation of the selected remedial action.''

The EPA, Region 4 and the South Carolina Department of Health and the Environment (SCDHEC) conducted the FYR and prepared this report regarding the remedy implemented at the Carolawn Site (the Site) in Fort Lawn, Chester County, South Carolina. The EPA and SCDHEC conducted this FYR for the entire Site from March 2013 to August 2013. The EPA is the lead agency for developing and implementing the remedy for the Superfund cleanup at the Site. The Carolawn Steering Committee (CSC) funds, performs and manages the environmental response activities at the Site. O'Brien & Gere (OB&G) and Geosyntec, on behalf of the CSC, implements operation, maintenance and monitoring (OM&M) activities as well as conducts data collection and analyses detailed in this report. This FYR references, extracts, summarizes, and/or edits information from the Carolawn Site documents provided in Appendix A. This report documents the results of the review.

The Site has two operable units (OUs). Below is a summary of the two OUs and their selected remedies. §ectioirll 4l.O provides a more complete description of each OU and their selected remedies.

o OU-I consists of a 3-acre area completely enclosed by a chain link fence and the areal extent of all groundwater contamination beneath the Site. During the 1980s, removal activities conducted

15

by the EPA and the CSC addressed the source of the groundwater contamination by removing drums, waste materials and contaminated soils. Due to the effectiveness of the removal actions, no source of contamination remains within the fenced area of the Site. The major components of the remedy included groundwater extraction, on-site treatment of the contaminated groundwater, and discharge of treated groundwater into Fishing Creek pursuant to a National Pollution Discharge Elimination System (NPDES) pem1it.

The remedy for OU-1 required additional investigation in the disposal area north of the fenced area (OU-2) to verify the presence or absence of contamination. In addition, the remedy provided for the implementation of institutional controls (deed restrictions). Further, the remedy required plugging of certain private wells in accordance with SCDHEC regulations.

• OU-2 is an undeveloped woodland area located beyond the fenced area of OU-1. OU-2 includes the soils, surface water and sediments in Fishing Creek. During the 1980s, the EPA removed drums, waste and contaminated soils from this area. Due to the effectiveness of the removal actions, no source of contamination remains in this area of the Site. Following an additional remedial investigation (RJ) and baseline risk assessment (BRA), the EPA selected no further action for the final remedy for OU-2.

This is the fourth FYR for the Site (OU-1 and OU-2). The triggering action for this 'statutory' review was the signing of the third FYR on September 25, 2008. The FYR is required because (1) contaminants remain in groundwater on-site above levels that allow for unlimited use and unrestricted exposure, and (2) the groundwater remedy will require five years or more to complete.

A list of documents (references) used in the preparation of this FYR follows Section 11.

The next Five-Year Review for the Site will be due in September 2018.

2.0 Site Chronology

Table 1 lists the dates of important events for the Carol awn Site.

3.0 Site Background

3.1 Physical Characteristics

The Site is located at 5093 Morrison Road, Fort Lawn, Chester County, South Carolina. A general site location map (USGS quadrangle) is included as Figure 1. A site plan including groundwater extraction, injection, soil vapor extraction and monitoring wells is included as Figure 2 and Figure 3. The Lancaster & Chester Railroad and County Road 841 border the Site to the south. Providence Fish & Game and Fishing Creek border the Site to the east. Circle S Farms borders the Site to the west. Wooded areas and cultivated fields lie to the west and north of the Site. There are four residences located approximately 1,000 yards southwest of the Site. The Site consists of two OUs. OU-I is a 3-acre area completely enclosed by a chain link fence and the areal extent of all groundwater contamination beneath the Site. OU-2 is primarily an undeveloped woodland area located beyond the fenced area of OU-1. OU-2 includes the soils, surface water and sediment in Fishing Creek.

16

Three overburden (rock material) units and granodiorite bedrock underlie the Site. The uppermost overburden unit consists of alluvial deposits. A discontinuous, colluvial and residual clay unit underlies the alluvium. The third overburden unit is comprised of residuum and saprolite, both products of in-situ weathering of the underlying bedrock. The residuum differs from the saprolite only in its degree of weathering. The saprolite retains the structure and mineralization of the present bedrock and residuum does not.

The bedrock, which underlies the saprolite, is coarse-grained, massive, olive-gray granodiorite. The reported bedrock surface elevations at the Site well locations range from 454 feet (ft) relative to mean sea level (msl) to 365 ft msl. Groundwater flow within the bedrock aquifer is dependent on secondary porosity, including fractures and joint sets. Joint orientations within the bedrock were measured in outcrops along creeks, road cuts and a railroad cut near the Site. Predominant joint sets, measured in outcrop, strike at N42°W, N5°W and N35°E and have vertical to sub-vertical dips. Besides joints, intrusive mafic dikes are the other major geologic structure present at and in the vicinity of the Site.

The overburden units were not observed to be water bearing, although the 1989 ROD references drought conditions at the time the RI was conducted as a possible explanation for the absence of groundwater in the saprolite. However, subsequent drilling activities conducted in 2004 confirmed the absence of groundwater in the overburden above bedrock. Groundwater beneath the Site occurs along joint/fracture planes in the bedrock, forming a bedrock aquifer. The occurrences of water bearing fractures are limited to the upper 50 ft of bedrock. Based on the RI conclusions, the mafic dike present beneath the Site has no measurable influence on groundwater flow.

Groundwater potentiometric elevations in the bedrock aquifer range from over 430 ft mean sea level (msl) to around 380 ft msl (adjacent to Fishing Creek). A groundwater potentiometric surface and flow map is included as Figure 4. The natural (non-pumping), horizontal groundwater hydraulic gradient in the bedrock aquifer across the Site ranges from 0.032 to 0.035 ft/ft with a generalized northeast and southeast flow toward Fishing Creek. The natural groundwater velocity was calculated to be between 0.02 to 1.5 ft/day.

Fishing Creek forms a hydraulic boundary to the northeast, east and southeast of the Site and is the discharge location for Site groundwater. The surface water elevations adjacent to Fishing Creek range from 383 ft ms! to 380 ft ms!. These surface water elevations are lower than Site groundwater elevations.

3.2 Land and Resource Use

Rural and agricultural areas surround much of the Site. Located within a two mile radius of the Site are approximately 30 permanent, single family residences, most of which are along South Carolina Highway 9, located north of and hydraulically upgradient or side gradient of the Site. The residential, commercial, and industrial establishments within the City of Fort Lawn receive their water supply from the Chester Metropolitan Sanitary District (MSD), whose water intake on the Catawba River is approximately four miles east of the Site and above the confluence of Fishing Creek and the Catawba River. There are four residences located approximately 1,000 yards southwest of the Site. The four residences who used private wells were provided an alternative water source in 1985 and connected to the Chester MSD. There are no known current

17

or planned uses of groundwater as a drinking water source or any other source on or in the vicinity of the Site.

All groundwater in South Carolina is classified as Class GB Waters (South Carolina Regulation 61-68). This classification means that all groundwater meeting the definition of underground sources of drinking water (USDW) meet quality standards set forth in the State Primary Drinking Water Regulations (R.61-58.5). An USDW is defined as an aquifer or portion of an aquifer that supplies or contains sufficient quantity of water to supply a public supply system.

Natural resources in the area of the Site include water, soils, flora, and fauna. The waters of Fishing Creek are occasionally used for fishing and other recreational activities, but topography and poor accessibility limit the use of the creek in the vicinity of the Site. Fishing Creek flows southward past the Site and eventually empties into the Catawba River, eight miles south of the Site and above Great Falls, South Carolina, where approximately 2,500 people receive their water supply from the Catawba River.

3.3 History of Contamination

The Southeastern Pollution Control Company (SEPCO) of Charlotte, North Carolina, originally owned the Site. Beginning in 1970, SEPCO used the Site as a storage facility for a solvent recovery plant located in Clover, South Carolina. SEPCO filed bankruptcy in 1974 and abandoned the Site, leaving approximately 2,500 drums of solvent on the Site. SEPCO had been storing the drummed solvents in anticipation of incinerating the waste. However, neither an incineration pennit nor a storage/disposal permit was issued to SEPCO by SCDHEC.

In January 1975, as part of the effort to clean up the SEPCO plant in Clover, South Carolina, the Columbia Organic Chemical Company (COCC) transported and stored approximately 2,000 drums at the Site. As payment for services rendered during the cleanup of the plant in Clover, South Carolina, COCC received the Carolawn property. After 1975, South Carolina Recycling and Disposal, Inc. (SCRO I), a subsidiary of COCC, controlled the Site. During 1978, SCRO I obtained a permit from SCDHEC for a one-time disposal of 300-400 drums containing inert waste.

In October 1978, SC RD I was given approval to dispose of empty drums on the fenced area of the property. After the disposal, SCRDI sold the fenced area of the Site to the Caro lawn Company. Between 1978 and 1980, the Carolawn Company conducted waste storage, treatment, and disposal operations within the fenced area. When the Carolawn Company abandoned the Site in 1980, the fenced area contained 2 incinerators, 2 storage trailers, 14 storage tanks, and over 400 drums containing liquid and solid wastes. Over 600 drums and 11 tanks were also located to the north of the fenced area.

3.4 Initial Response Action

During the early 1980s, SCDHEC and the EPA conducted investigations at the Site. These investigations included collecting environmental samples and private residential well samples for analysis. The result of these investigations showed the presence of trichloroethene (TCE) and other solvents in nearby residential wells. The results also indicated that the Site was contaminated with high levels of metals and organic compounds. Due to the elevated levels of contamination found and the potential imminent threat for damage to public health and/or the

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environment, the EPA initiated cleanup activities at the Site on December 1, 1981. The cleanup activities continued through February 1982 and included removal of contaminated soils, drums, and liquid waste from the Site.

In December 1982, the Site was proposed for inclusion on the National Priorities List (NPL). The Site was finalized on the NPL on September 8, 1983. The NPL is a list of priority releases for long-term evaluation and remedial response, and was promulgated pursuant to section 105 of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980, as amended. The NPL list is found in the NCP (Appendix B of 40 CFR part 300).

At least one of the local residential wells showed persistently high levels of volatile organic compounds (VOCs) during different sampling events. Therefore, the EPA extended the Chester MSD's water main from Highway 9 to four residences living near the Site. These four residents were connected to this alternative water supply in 1985.

In May 1985, a group of Potentially Responsible Parties (PRPs), the Carolawn Steering Committee (CSC), entered into an Administrative Order on Consent (AOC) to remove seventeen storage tanks off-Site and dispose of the waste contents at an incinerator. In addition, the CSC treated the water from decontamination activities, and excavated and disposed of contaminated soils.

3.5 JBasns for Taking Action

Pursuant to a Consent Decree, the CSC conducted a removal action at the Site in 1986, and a multi-phase Remedial Investigation/Feasibility Study (RI/FS) between 1986 and 1989. Phase I of the RI/FS concluded in March 1987. Phase II of the RI/FS was initiated in the fall of 1987 and was completed in September 1989. These studies identified VOCs in groundwater as the only contaminants of concern (COCs) with the potential to pose unacceptable risk to human health or the environment. Former waste storage drums and tanks were identified as the source of these COCs. The specific findings of the RI for OU-I as described in the Rl/FS report dated November 1989 and the Proposed Plan for OU-1 are summarized as follows:

Remedial Investigation (RI) for OU-1

Surface and Subsurface Soils The surface and subsurface soil samples collected during Phase I of the RI/FS were analyzed for the EPA Priority Pollutant List VOCs, Base Neutral/Acid Extractables (BNAs), and total metals. Methylene chloride and acetone were detected in all surface soil samples. However, these compounds were also detected in the laboratory blanks and therefore are likely the result of laboratory contamination. Bis(2-ethylhexyl)phthalate was the only BNA detected in three samples ranging from 790 micrograms per kilogram (µg/kg) to 55,000 µg/kg. The cleanup goal for bis(2-ethylhexyl)phthalate is 120,000 µg/kg. Several metals were detected in the surficial soil samples. The highest concentrations were lead (160 milligrams per kilogram (mg/kg), chromium (93 mg/kg) and barium (320 mg/kg). The cleanup goal for lead, chromium, and barium are 800 mg/kg, I 00,000 mg/kg, and 67,000 mg/kg, respectively.

Methylene chloride was the only VOC detected in subsurface soil samples and is likely the result of laboratory contamination. Bis(2-ethylhexyl)phthalate was the only BNA detected in one sample at a concentration of 330 µg/kg. The metal concentrations detected in the subsurface soil

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samples are generally lower than the metal concentrations detected in the surface soil samples. Therefore, the presence of metals is within naturally occurring levels.

Surface Water and Sediment in Fishing Creek The surface water samples collected during Phase I of the Rl/FS were analyzed for the EPA Priority Pollutants. Water samples were collected from Fishing Creek and an intermittent stream. The only compound detected in Fishing Creek was methylene chloride. This compound was detected in laboratory blanks and therefore is ascribed to laboratory contamination. All other compound types, including BNAs, polychlorinated biphenyls (PCBs) and metals were below detection limits.

All Phase II surface water samples collected were analyzed for Target Compound List (TCL) VOCs. Examination of these data indicates that only acetone (91 µg/L at one location) was detected. At the time of the 1989 ROD, the value of 700 micrograms per liter (µg/L) was a lifetime health advisory. No other VOCs were detected. In addition, the EPA determined that the presence of acetone was the result of laboratory contamination, as acetone was not detected in a duplicate sample. Therefore, the surface water analyses conducted during the RI indicate that the discharge of groundwater has not had a measurable impact on the water quality in Fishing Creek.

The sediment samples collected from the drainage courses near the Site and from Fishing Creek were analyzed for EPA Priority Pollutants. Several metals were detected in the sediment samples. However, all metal concentrations appear to be within naturally occurring levels. This indicates that surface water runoff and overland flow from the Site has not resulted in the accumulation of particulate contaminants in the ditches, intermittent stream or Fishing Creek.

Groundwater Two rounds of groundwater samples were collected during Phase I. The first round of samples was analyzed for the EPA Priority Pollutants. The second round of samples was analyzed for select inorganics and VOCs. The results of the RI concluded the only environmental media that remains contaminated at levels requiring remediation is groundwater. The hydraulic data collected during the RI concluded Fishing Creek is the primary receptor of the groundwater flowing underneath the Site. The RI concluded that the contaminants are being transported through the fractures and joints in the bedrock along with the groundwater. As stated previously, the mafic dike has little effect on groundwater flow and therefore, the distribution of the contaminants in the groundwater.

The RI indicated the presence of COCs in the groundwater downgradient and beyond the property lines of the Site at concentrations above the cleanup goals specified in Table 2 of this FYR. Below are brief descriptions of the findings of the groundwater investigation. Several TCL VOCs were detected in the monitoring wells and domestic wells sampled during Phase I and II of the RI/FS. The VOCs detected in both rounds and their range in concentrations were:

voe Range in Concentrations acetone Not Detected - 31,000 µg/L 1, 1. -dichloroethane Not Detected - I 0 µg/L 1, 1-dichloroethene Not Detected - 170 µg/L 1,2-dichloroethane (total) Not Detected- 470 µg/L I,1, 1-trichloroethane Not Detected - 63 µg/L trichloroethene Not Detected - 1,200 µg/L

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methylene chloride (Phase I only) Not Detected - 17 µg/L

Bis(2-ethylhexyl)phthalate, a common cross-contaminant was the only BNA detected in one monitoring well in Phase I, but not in Phase II of the RI. Neither PCBs nor pesticides were detected in any groundwater samples collected during the Rl. A number of Target Analyte List (T AL) metals were detected in the Phase I samples and in two groundwater samples during Phase II. Lead was detected at concentrations from 2.6 µg/L to 28.0 µg/L in various monitoring wells in Phase I. Lead was also detected in Phase II at concentrations of 8.2 µg/L and 80 ~tg/L, respectively. In September I 989, the Maximum Contaminant Level (MCL) for lead was 50 µg/L. However, the current MCL for lead is 15 µg/L. In addition, chromium was detected in one monitoring well at a concentration of 80 µg/L. In September 1989, the MCL for chromium was 50 µg/L. However, the current MCL for chromium is 100 µg/L.

Baseline Risk Assessment (BRA) for OU-I

A BRA was conducted to evaluate the risks to human health and the environment, under present­day conditions and under assumed future use conditions. The BRA considered the potential release mechanisms to the five primary, environmental media of concern: air, soils, surface water, sediment, and groundwater.

The BRA identified the following potential human exposure pathways associated with the Site:

s inhalation, consumption and dermal contact of contaminated groundwater; e1 inhalation, consumption and dermal contact of contaminated surface water; and e consumption of contaminated fish from Fishing Creek.

The COCs identified for the Site are VOCs and one heavy metal. More specifically: acetone, I, 1­dichloroethane (l, 1-DCA), I, 1-dichloroethene (I, 1-DCE), l ,2-dichloroethene (1,2-DCE), 1, l, !­trichloroethane ( 1, 1, 1-TCA), trichloroethene (TCE) and lead.

Air The BRA determined the risk posed by the inhalation of vapors and suspended contaminated particulates in air has a very low probability. Although the COCs for the Site are VOCs, the removal of the contaminated soils and subsequent back filling with clean fill by the EPA in I 982 eliminated the air pathway as an exposure pathway of concern. Therefore, the EPA determined a remedial action was not warranted for this medium.

Soils Due to the EPA' s 1982 removal action and the PRP sponsored 1986 removal action, the metals in the surface soils were detected at concentrations below cleanup goals. Furthermore, exposure to soil is not considered a risk and the 1982 removal action eliminated the soil pathway as an exposure pathway of concern. Therefore, the EPA determined a remedial action was not warranted for the soils within the fenced area of the Site. However, at the time of the BRA for OU-1, some uncertainty existed with respect to the area north of the fenced area that was used for storage (OU-2). Although this area was addressed during the EPA removal action, insufficient confirmatory data was generated to substantiate the absence or presence of soil contamination. In 1994, confirmatory data was collected during the RI for OU-2. A summary of RI activities for OU-2 is provided in Section 4.2.2.

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Surface Water and Sediment in Fishing Creek The BRA concluded the estimated lifetime cancer risk due to exposure to COCs that are present in Fishing Creek ranges from 7.3 x 10- 11 to 4.8 x 10- 12 for swimmers. This is below the acceptable range of 1 x 10-4 to I x 10-6. Consequently, there is no increase in health risks to swimmers due to the exposure to COCs for the Site in Fishing Creek.

Using the assumptions that an individual consumes between 14 to 42 grams of fish per day for his entire lifetime and that 10 percent of these fish consumed come from Fishing Creek, the estimated increased lifetime risk of cancer ranges from 1.7 x Io-8 to 2. 7 x 1o-9

. This range also falls below the acceptable range of I x I 0-4 to 1 x 1o-6

. Consequently, there is no quantifiable increase in the health risk due to the consumption of fish caught in Fishing Creek. Following the conclusion of the BRA, the EPA determined a remedial action was not warranted for the surface water and sediments in Fishing Creek.

Groundwater The BRA concluded the estimated lifetime cancer risk due to exposure to COCs in the groundwater ranges from 1.64 x 10-3 to 8.40 x 1o-5

. This risk range is above the range ofrisks 1 x 10-4 to 1 x 1 o-6 considered by the EPA to be protective of public health. Therefore, groundwater at these levels of contamination is unacceptable for human consumption. Following the conclusion of the BRA, the EPA determined a remedial action for groundwater was warranted to protect the public and the environment, which was actually implemented as OU-1.

Sensitive Environments The BRA concluded no endangered species were identified living on or near the Site, and the Site does not impact any sensitive environments.

Feasibility Study (FS) for OU-1

A FS was conducted to identify alternatives to address the potential risks posed by the Site. Based on the BRA, FS, and the ARARs for OU-1, the Remedial Action Objectives (RAOs) listed in Section 4.1.1 were established for the Site. Alternatives were developed with the goal of attaining these RAOs. Upon completion of the RI, BRA and the FS, the EPA issued a Proposed Plan in August 1989 identifying the EPA' s preferred remedy to the public and starting the period for public comment. The EPA prepared a ROD for OU-I to address the potential risks posed by the Site. Cleanup goals for groundwater were selected by using MCLs and proposed MCLs, if available, or by using toxicological data reviewed by the EPA for contaminants that did not have MCLs. The groundwater cleanup goals are summarized in Table 2 of this FYR and in the ROD.

4.0 Remedial Actions

In accordance with CERCLA and the NCP, the overriding goals for any remedial action are protection of human health and the environment and compliance with ARARs. A number of remedial alternatives were considered for the Site, and final selection was made based on an evaluation of each alternative against nine evaluation criteria that are specified in Section 300.430(f)(5)(i) of the NCP. The nine criteria include:

1. Overall Protectiveness of Human Health and the Environment, 2. Compliance with ARARs, 3. Long-Term Effectiveness and Pennanence,

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4. Reduction of Toxicity, Mobility or Volume of Contaminants through Treatment, 5. Short-tenn Effectiveness, 6. Implementability, 7. Cost, 8. State Acceptance, and 9. Community Acceptance.

As noted in Section 3.5, the EPA determined that risks to human health from the groundwater are not within the EPA' s acceptable risk range and the contaminant concentrations in groundwater are not acceptable for human consumption. Therefore, remediation of groundwater was required for the protection of human health. On September 27, I 989, the EPA issued a ROD for OU-I (I 989 ROD) to address the groundwater contamination at the Site and to require additional soil sampling for soils located beyond the fenced OU-I. To address the soils located beyond the fenced OU- I, the EPA conducted RI activities on OU-2 and issued a ROD for OU-2 (I995 ROD) for no further action on September 21, 1995. An additional discussion on activities for OU-2 is provided in Sectio1111 4.2.2.

4.1 Remedy Selection

4.1.1 Remedial Action Objectives (:RAOs) for OU-1

As stated within the 1989 ROD, the purpose of the remedial action at the Site is to minimize, if not mitigate contamination in the groundwater and to reduce, if not eliminate, potential risks to human health and the environment. The following remedial action objectives (RAOs) were determined based on regulatory requirements and levels of contamination found at the Site:

e prevent the near-term and future exposure of human receptors to contaminated groundwater both on and off site,

r;i restore the contaminated aquifer for future use by reducing contaminant levels to those which will adequately protect human health and the environment,

Q control contaminant migration so contaminant releases from groundwater to Fishing Creek do not exceed clean up criteria to human health and the environment,

ai monitor groundwater in a manner to verify effectiveness of remedial measures, and • confirm absence or presence of soil contamination in storage area north of the fenced area

(OU-2).

4.1.2 Components of the Selected Remedy for OU-1

Section 121 (d)(2)(A) of CERCLA specifies that Superfund remedial actions must meet any federal standards, requirements, criteria, or limitations that are determined to be ARARs. ARARs are those standards, criteria or limitations promulgated under federal or state law that specifically address a hazardous substance, pollutant, contaminant, remedial action, location, or other circumstance at a CERCLA Site. To-Be-Considered criteria (TBCs) are nonpromulgated advisories and guidance that are not legally binding, but should be considered in determining the necessary level of cleanup for protection of human health or the environment. While TBCs do not have the status of ARARS, the EPA's approach to determining if a remedial action is protective of human health and the environment involves consideration of TBCs along with ARARs.

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Chemical-specific ARARs are specific numerical quantity restrictions on individually listed contaminants in specific media. Examples of chemical-specific ARARs include the MCLs specified under the Safe Drinking Water Act as well as the Ambient Water Quality Criteria that are enumerated under the Clean Water Act. Because there are usually numerous contaminants of potential concern (COPCs) for any Site, various numerical quantity requirements can be ARARs. The final remedies selected for this Site were designed to meet all chemical-specific ARARs and meet location-specific and action-specific ARARs.

As discussed earlier, the 1989 ROD noted that groundwater is the primary environmental medium of concern where concentrations of contaminants remain that could potentially impact the public health and the environment. The chemical-specific ARARs identified in the 1989 ROD for the groundwater at this Site and considered for this FYR for continued groundwater treatment and monitoring are listed in Table 2 (Page 22). Table 2 provides a summary of the COCs in the groundwater, the specific cleanup goal for each COC, and the source for the specified ARARs, as described in the 1989 ROD.

The major components of the selected remedy included:

Migration Control (remediation ofcontaminated groundwate1) Installation of a groundwater interception and extraction system at the Site. The level and degree of treatment of the extracted groundwater depends on the following:

1. the ultimate discharge point of this water, and 2. the level of contaminants in the extracted groundwater.

The remedy provided the following water discharge alternatives for the treated groundwater:

1. the local sewer system, (i.e., publicly owned treatment works), 2. Fishing Creek via a National Pollution Discharge Elimination System (NPDES) permit

or, on-site irrigation, and 3. groundwater injection.

The range of treatment for the extracted groundwater included air stripping, biodegradation, and filtration through activated carbon filter and metal removal. The most cost effective combination for the point of discharge and the degree of treatment was determined in the remedial design stage. The discharged water should meet all ARARs. Concurrence on the final design was requested from the state of South Carolina. Comments were solicited from the public on the final design.

The existing groundwater monitoring system should continue to be reviewed to ensure proper monitoring of groundwater. If deemed necessary, additional monitoring wells will be installed to mitigate any deficiencies in the existing groundwater monitoring system.

Implement appropriate institutional controls (deed restrictions).

Upon the condemnation of the adjacent contaminated private potable wells, by the County of Chester, the wells should be abandoned in accordance with SCDHEC's regulations.

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General Site Cleanup Activities The two inactive incinerators should be inspected and any remaining residue will be sampled and analyzed. Wipe samples will be collected and analyzed. The results of the analyses will determine the method. of disposition for the incinerators. The two remaining drums will also be sampled and analyzed to determine how they will be disposed. In addition, site cleanup will include closing of the equipment decontamination area used during Phase I RI activities.

Operations and Maintenance Long term operation and maintenance (O&M) will concentrate on the groundwater extraction, water treatment and groundwater monitoring systems.

Source Control (Remediation ofContaminated Soils) Due to the effectiveness of the removal actions, no source of contamination remains within the fenced area of the Site. However, additional fieldwork was required in the disposal area north of the fenced area. This fieldwork consisted of the installation of confirmatory soil borings to verify the presence or absence of contamination in this area. If no contamination is found, no source control remediation will be required at the Carolawn site. To address the soils located beyond the fenced OU-I, the EPA conducted RI activities on OU-2 and issued a ROD for OU-2 (1995 ROD) for no further action on September 21, 1995.

4.2 Remedy Implementation of OU-1

4.2.1 Migration Control

Overview of Groundwater Remediation/Site Cleanup, Well Closure and IC Activities On December 2, 1991, the EPA issued a Consent Decree to the CSC to perfom1 Remedial Design (RD) and Remedial Action (RA) activities. From December 1991 through May 1992, Conestoga Rovers & Associates (CRA), on behalf of the CSC, implemented several components of the RA, which included the closure of at least three residential wells (which were no longer in use), appropriate closure of the RI decontamination area and installation of a water service to a resident.

The RA was formally initiated on May 12, 1993, upon the EPA's approval of the RD. The groundwater extraction and treatment system (GWETS) was constructed by CRA and ENSR under the direction of the EPA and SCDHEC. The complete GWETS was installed during the period of December 1995 through June 1996. The GWETS consists of five groundwater extraction wells (EW-1, EW-2R, EW-3R, EW-4 and EW-5). Each extraction well is equipped with a pneumatic submersible pump and associated level sensors/controls. The extraction wells are constructed with steel casing set 5 to 7 ft into bedrock and open-hole construction to the completion depth. The completion depth ranges from 160.2 to 183 .5 ft below ground surface (bgs), corresponding to completion elevations of 277.9 to 256.6 ft msl for EW-2R, EW-3R, EW­4 and EW-5. The completion depth of EW-1 is 79.9 ft bgs (elevation 329.5 ft ms!). In contrast, Site monitoring wells, also constructed as open-hole bedrock wells (with the exception of MW­11 A), have completion depths ranging in elevations from 401.6 to 270.6 ft msl. Based on drilling observations, fewer water-bearing joints/fractures were encountered 50 to 60 ft below the bedrnck surface.

The treatment system consists of two processes, which may be operated separately or in series configuration. The treatment processes are identified as the Air Stripping/Clarification process

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and the Bag Filter/Granular Activated Carbon (GAC) Adsorption process. The Air Stripping/Clarification process was utilized as the primary treatment process. The Bag Filter GAC Adsorption process could provide secondary treatment or treatment while the Air Stripper is being maintained. However, the Bag Filter GAC Adsorption process was never used since the Air Stripping process operated as designed and reduced VOC concentrations in extracted groundwater to levels below the NPDES permit discharge limits.

Although ICs were required by the ROD for OU-I, ICs have not been implemented at the Site since there is no viable owner willing to execute and record ICs. The defunct Carolawn Company is still listed as the property owner. Therefore, the EPA has not identified a property owner for the Site. The Site is currently not in use. There are currently no residential well users on the Site or within the contaminated area of the VOC plume. The four residences closest to the Site who used private wells were provided an alternative water source in 1985 and connected to the Chester MSD.

GWETS - Groundwater Remediation Construction Activities On December 7, 1995, ENSR, a subcontractor of CRA was issued the Notice to Proceed for construction activities. Mobilization of trailers and setup of the Site support area were completed during the week of January 15, 1996. The discharge line was installed between February 20, 1996 and March 14, 1996. Completion of the access road was executed from April 10, 1996 to April 16, 1996. .

The treatment building excavation was completed on March 5, 1996, and the dewatering bed and sump chamber were installed on March 9, 1996. Installation of the force mains was performed concurrently with construction of the treatment building. Trenching, installation, and backfilling of the force mains and electrical conduits were completed from April 2, 1996 to April 18, 1996. The groundwater extraction well pumps were installed on April 23, 1996 and April 24, 1996. Installation of mechanical components occurred from May 11, 1996 to June 5, 1996.

Construction of the GWETS was completed on June 8, 1996. SCDHEC completed a Pre-Final Inspection of the G WETS on June 11, 1996, while the EPA conducted this same inspection on June 12, 1996. Minor construction items were identified during the week of June 10, 1996. However, all items were completed by July 5, 1996. The Permit to Operate the GWETS was issued on June 14, 1996. Commissioning of the GWETS began on June 15, 1996. However, the commissioning period was reduced to two weeks as negotiated with SCDHEC, because the NPDES permit had not been finalized. The CSC voluntarily began operation of the GWETS on October 9, 1996. The EPA in conjunction with the Carolawn Community Advisory Group (CAG) conducted a Final Inspection of the GWETS on October 10, 1996. The GWETS began operation pursuant to the Unilateral Administrative Order (UAO) for operation, maintenance, and monitoring, issued by the EPA to the PRPs on July 28, 1997.

In October 1997, the CSC's benthic study of Fishing Creek (near the Site), conducted by Shealy Environmental Services, Inc., determined that the Site NPDES discharge had not had any impact on benthic community in Fishing Creek, and the test demonstrated that the treated groundwater discharge was not toxic. Concurrent with the operation of the GWETS, the Carolawn NPDES Permit was modified on April 2, 1998, which allowed the use of a diffuser requiring only effluent chronic testing at the in-stream waste concentration of 1.02%, in lieu of the then current acute test at 100% effluent. The Preliminary Close Out Report was completed on May 18, 1998, following SCDHEC's approval of the permit modification.

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Operation and Maintenance of the GWETS was conducted between October 1996 and July 2004. The operation and maintenance of the GWETS was comprised of three primary activities: (1) physical operation and maintenance, (2) monitoring and evaluation activities; and (3) reporting and recordkeeping. The objective of the operation and maintenance activities was to ensure that the constructed treatment facilities were operated correctly and maintained in good working order, and that associated recordkeeping and reporting were conducted throughout the O&M period. The objective of the groundwater monitoring program is to monitor the progress and effectiveness of remediation in attaining the RA Os. The groundwater monitoring program will continue to be conducted post-shutdown period (July 2004). Monitoring wells presented on Figure 2 are used in the groundwater monitoring program.

GWETS Evaluatio11 The G WETS operated from October 1996 to July 2004. A summary of groundwater concentrations of historic COCs for Site monitoring wells and extraction wells from 1988 to February 2007 is presented in the third FYR Report issued on September 25, 2008. The conclusions of the GWETS evaluation conducted in 2004 after 7.0 years of operation are summarized as follows:

• The operation of the GWETS satisfied the RAOs through the reduction of contaminant mobility and volume in the aquifer via groundwater extraction and air stripping to remove VOCs, prior to discharge to Fishing Creek.

• Approximately 19.2 million gallons of groundwater and 16 kg of VOCs (35 lbs of TCE) were extracted by the GWETS from the bedrock VOC plume during a 7-year period.

• The hydraulic control of the G WETS, potentially enhanced by natural attenuation processes did result in a reduction in the spatial extent of the higher voe concentrations in groundwater.

• Further, several monitoring wells exhibited declining trends in groundwater TCE concentrations, including wells where TCE concentrations were initially increasing at the start of the GWETS.

• The GWETS extraction rates and volumes were significantly limited due to groundwater drawdown below fractures in the extraction wells in the low yielding granodiorite aquifer.

• The use of a groundwater extraction well network did limit contaminant transport, and mitigated the further migration of voes.

• After 7 years of extraction, only 0.1 to 0.5 aquifer pore volumes (PY) were extracted each year from the five extraction wells.

• Using a simplified PV approach, it is estimated that the GWETS would have to have operated for at least an additional 62 years (in absence of retardation and other assumptions) to achieve MC Ls, due primarily to the low yield of the bedrock formation.

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Although operating as designed, the data collected between 1996 and 2003 indicated the GWETS would not be effective in reducing VOC groundwater concentrations to acceptable levels within ten years as described in the 1989 ROD due to site-specific hydraulic challenges. As a result of the second FYR, the EPA and SCDHEC recommended a system optimization study which considers the use of alternative remedial technologies to address VOCs in groundwater.

E11ha11ced In Situ Biodegradatio11 (EJSB) - Pilot Study In response, the CSC prepared the August 2004 Remediation System Evaluation Report and Action Plan (Action Plan). The purpose of the Action Plan was to present the results of the GWETS evaluation and a follow-up action plan for the Site. In addition, the Action Plan provided a workplan for the "pilot study" for Enhanced In Situ Biodegradation (EISB) of groundwater, including shutdown of the GWETS and modifications to OM&M activities. The CSC shutdown the GWETS on July 19, 2004.The shutdown of the GWETS included pump removal and system decommissioning. The pump removal and system decommissioning was conducted in a manner such that the GWETS can be operational within a timely manner, in the unexpected event that resumption of operation is necessary.

The EISB application was designed to target the portion of the plume with groundwater concentrations equal or greater than 500 µg/L. The CSC completed EISB injection of a substrate consisting of a soy-oil based product known as Newman Zone in May 2005. The EISB approach involved the injection of Newman .Zone into fourteen new and two existing (former extraction) wells to provide a slowly releasing source of electron donor to the native halorespiring microbial population to promote accelerated biodegradation of VOCs. The data from the post-injection monitoring events (summarized in the third FYR Report) indicated biodegradation occurred and has been enhanced in a limited groundwater area in response to the Newman Zone injection. However, 4 years after injection, these conditions were not widespread and biodegradation has slowed at individual locations due to donor limitation, resulting from insufficient transport of the Newman Zone away from the injection boreholes. Furthermore, the overall plume extent and voe concentrations did not change significantly in response to enhanced biodegradation in the granodiorite aquifer. Based on the remedial progress observed between 2003 and 2008, the third FYR recommended further evaluation of technologies other than the GWETS and EISB to identify a remedy that would more effectively and efficiently restore the contaminated aquifer for future use.

Soil Vapor Extraction (SVE) System - Pilot Study In March 2009, the EPA issued a Modified Unilateral Administrative Order (UAO) to the CSC which required a Focused Feasibility Study (FFS) to identify a groundwater remedy more favorable than the GWETS. The CSC submitted a draft FFS to EPA in January 2010 and subsequently met with the EPA to discuss the same. In August 2010, the CSC conducted a soil vapor extraction (SVE) 'pilot study' to co Hect data to evaluate the potential use of SVE as an Interim Remedial Measure (IRM) as part of an overall groundwater remediation strategy. The results of the SVE study indicated SVE as a feasible approach to reduce VOC mass in the subsurface (vadose zone) which could result in reduced VOC concentrations in groundwater. Following discussions with SCDHEC, the CSC and the Community Advisory Group (CAG), the EPA issued the Notice to Proceed with the remedial design and construction of the SVE system. Construction of the SVE system was completed in January 2012. Operation of the SVE system has reduced voe mass from the subsurface and is expected to reduce the flux of voes to groundwater which will allow groundwater concentrations to decline over time. Approximately

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155 lbs of voes have been removed during seventeen months of SVE system operation. SVE system operational data and groundwater plume monitoring suggest voe conditions are improving, source area mass is reducing, and the VOC groundwater plume is generally stable and decreasing.VOC mass removal from the SVE system will continue to be monitored to assess the impact of the SVE System on groundwater conditions. In addition, this perfom1ance data will be used to support completion of the FFS which could lead to modifying the 1989 ROD. The results of the SVE System pilot study are described in Sections 6.4.2.

4.2.2 Source Control (Remediation of Contaminated Soils)- OU-2

In an effort to address components of the 1989 ROD, the EPA conducted a RI and BRA on OU­2, focusing mainly on soils (surface/subsurface) in the disposal areas outside the fenced area and the surface water and the sediment in Fishing Creek. The main portion of the RI was conducted in May 1994. Additional RI activities were conducted in October 1994. The specific findings of the RI for OU-2 as described in the RI and the Proposed Plan for OU-2 are summarized as follows:

Human Health

Surface and Subsurface Soil The results of the surficial soil analyses indicated the presence of several CO PCs in the soil cover. These compounds include arsenic, barium, beryllium, calcium, chromium, copper, iron, lead, magnesium, manganese, sodium, and PCBs. The results of subsurface soil analyses indicated that there are several COPCs. These compounds include arsenic, barium, copper, lead, manganese, mercury, zinc, PCBs, tetrachloroethene and toluene. Other concentrations of inorganics and organics were detecte"d in the soil (surface and subsurface). However, the concentrations of these contaminants were below the background concentration ranges for native soils or were below human health protective threshold standards established by the EPA.

Surface Water and Sediment in Fishing Creek There were no COPCs identified for surface water. In addition, no VOCs, extractable organic compounds, pesticides or PCBs were detected in any of the samples. Metals were detected in all of the surface water samples. However, the concentrations of these contaminants were below the background concentration ranges. The sediment analyses revealed arsenic as the only COPC in sediment. However, no VOCs, pesticides or PCBs were detected in any of the sediment samples.

Groundwater A groundwater remedy was selected for OU-I. Therefore, groundwater was not evaluated in the RI or the BRA for OU-2.

Environmental Health

Soil The results of the surficial soil analyses indicated the presence of several contaminants of potential ecological concern (COPECs) in the soil cover. These compounds include arsenic, barium, copper, lead, manganese, mercury, zinc, PCBs, tetrachloroethene, and toluene. Other concentrations of inorganics and organics were detected in the soil. However, the concentrations of these contaminants were below the typical background concentration ranges for native soils or were below ecologically protective threshold standards established by the EPA.

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Sediment With the exception of barium, all chemicals detected in sediment were eliminated as an COPEC. Barium was unable to be eliminated from sediment during the screening process, because no screening value or background concentration was available for this compound. However, barium is not likely to cause a threat to the aquatic environment because it nonnally precipitates out of solution as an insoluble salt and.therefore is less bioavailable to aquatic organisms. It is unlikely that terrestrial organisms will come in direct contact with the sediment at the Site. Therefore, it is unlikely that barium in sediment will pose a significant risk to terrestrial organisms at the Site. In addition, barium is not known to bioaccumulate; therefore, this limits the possibility that terrestrial as well as aquatic organisms will come into direct contact with these contaminants through the food chain. For these reasons, exposure of terrestrial and aquatic organisms to barium in sediment was not further evaluated in BRA for OU-2.

Baseline Risk Assessment (BRA) for OU-2

A BRA for OU-2 was conducted to evaluate the risks to human health and the environment, under present-day conditions and under assumed future use conditions.

Human Health Risk

The BRA for OU-2 considered the potential release mechanisms of CO PCs from the Site to two primary, environmental media of concern: soils, surface water and sediment. There were no COPCs identified for surface water. Therefore, exposure to surface water is not considered a potentially significant risk to human health or the environment and the surface water pathway was eliminated as an exposure pathway of concern. Furthermore, the EPA detennined a remedial action was not warranted for the surface water in Fishing Creek.

Potential human exposure routes (for adults and children) evaluated in the BRA for OU-2 included the following:

• Incidental ingestion of surficial soil, • Dermal contact with surficial soil, • Incidental ingestion of sediment from Fishing Creek, and • Dermal contact with sediment in Fishing Creek.

Future potential exposure routes for adults and children associated with Site development that were evaluated included all of the scenarios listed above in addition to the following:

• Incidental ingestion of subsurface soil, and • Dermal contact with subsurface soil.

The BRA for OU-2 concluded the carcinogenic risk estimates for current and future conditions are either below the lower limit 1 x 1 o-6 or within the EP A's acceptable range of 1 x 10-4 to 1 x 10·6

. Furthermore, no noncarcinogenic hazard indices exceeded the EPA's acceptable level of 1.0. Therefore, the EPA determined that risks to human health from contaminants in the soil and sediment are within the EPA's acceptable risk range and that remediation of the soil and sediment would not be required for the protection of human health.

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Environmental Risk

A qualitative risk assessment was conducted to determine if COPECs posed an unacceptable risk to the ecological receptors on and near the Site. All COPECs and the media of concern (surface soil) were evaluated in the ecological section of the BRA for OU-2. At the Site, the terrestrial habitats present on the Site property include upland habitats. The American robin and the eastern cottontail rabbit are common terrestrial species inhabiting upland habitats. Because these two species are common in upland habitats as well as the study area, and a complete exposure pathway exists to these receptors via soil, they were used as surrogates to represent the terrestrial species exposed to contaminated surface soils at the Site.

The Hazard Quotient (HQ) method was used to define potential risk to the two representative terrestrial receptors via the soil exposure pathway. This method involves:

1. Estimating the exposure of each receptor species to COPECs by ingestion of contaminated food and/or soil;

2. Determining from past scientific studies the highest exposure level which produces no observed adverse effects (NOAEL) and the lowest exposure level which produces observed adverse effects (LOAEL) in the representative species; and

3. Dividing the estimated receptor species exposure level by the NOAEL and LOAEL. A LOAEL based HQ greater than 1 is indicative that there may be a potential for adverse effects on the receptor species.

Using the American robin as a potential receptor for the soil exposure pathway, the LOAEL HQ values ranged from 4. 7E-6 to 6.1 E-1 and the NOAEL HQ values ranged from 4. 7 E-5 to 6.1. In accordance with the EP A's guidance for Ecological Risk Assessments, remedial goals for the protection of ecological receptors should be bounded by the NOAEL value on the lower end and the LOAEL value on the upper end. Thus, the risk range is between 6.1 E-1 to 4. 7 E-5 which does not exceed the EP A's acceptable level of 1.0.

Using the eastern cottontail rabbit, a potential receptor for the soil exposure pathway, the LOAEL values ranged from 8.8E-8 to 6.2E-3 and the NOAEL values ranged from 8.8E-7 to 6.2E-2. In accordance with the EPA's guidance for Ecological Risk Assessments, remedial goals for the protection of ecological receptors should be bounded by the NOAEL value on the lower end and the LOAEL value on the upper end. Thus, the risk range is between 6.2 E-3 to 8.8E-7 which does not exceed the EPA's acceptable level of 1.0.

In summary, the EPA determined that risks to the ecological receptors from contaminants in the soil are within the EP A's acceptable risk range and that remediation of the soil would not be required for the protection of the environment.

Feasibility Study (FS) for OU-2

Based upon the results of the RI and BRA for OU-2, the EPA detern1ined that the surface and subsurface soils and surface water and sediment in Fishing Creek do not pose unacceptable risks to the public or the environment: and, therefore, a FS and a remedial action for OU-2 were not warranted. On September 21, 1995, the EPA signed a ROD for OU-2 (1995 ROD) for no further action.

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4.3 GWETS and SVE System Operation, Maintenance and Monitoring Costs

The 1989 ROD indicated cleanup levels. would be attained within I 0 years following commissioning of the GWETS. The estimated 1989 ROD present worth cost (aeration treatment and discharge to Fishing Creek) over 10 years was $1, 141,071. The estimated capital costs and present worth operation and maintenance· costs over 10 years was $504,807 and $636,264, respectively. This calculates to projected annual O&M costs of $90,589 for ten years, assuming 7% interest. The estimated 1989 ROD present worth cost (aeration treatment and discharge to Fishing Creek) over 30 years was $1,403,634. The estimated capital costs and present worth operation and maintenance costs over 30 years was $504,807 and $898,828, respectively. This calculates to projected annual O&M costs of $72,433 for thirty years, assuming 7% interest.

Since the ROD issuance, the CSC spent approximately $6,000,000 to implement the remedy selected in the 1989 ROD for OU- I. Prior to the G WETS shutdown, O&M costs were $200,000 to $250,000 per year. Remedial strategies relating to the SVE pilot study activities, including SVE system construction, monitoring and O&M costs as well as the continued comprehensive groundwater monitoring program, have averaged approximately $225,000 per year.

5.0 Progress Since the Last Five-Year Review

The protectiveness statement from the 2008 FYR stated:

"The remedy at the Caro/awn Site is protective in the short term since there is no complete exposure pathway to contaminated groundwater and the groundwater extraction and treatment remedy isfimctioning as intended by the 1989 ROD. However, in order/or the remedy to remain protective in the long term until ARARs or risk-based pe1formance standards spec(fied in the 1989 ROD are met, !Cs restricting groundwater use should be implemented at the Caro/awn Site on all properties where contamination from the Caro/awn Site has spread above cleanup goals spec(fied in the I 989 ROD.

The EPA should continue evaluating available groundwater treatment technologies to determine whether an alternative technology would be more e._ffective and e._fjicient than the existing groundwater extraction and treatrnent remedy in addressing the Site's remedial action o~;ectives. ·'·'

The 2008 FYR included 4 issues and recommendations. Table 3 summarizes each recommendation and the current status.

5.1 Modify the 1989 ROD to include Vinyl Chloride as a performance measure

The 1989 ROD has not been modified to include Vinyl Chloride as a performance measure. The EPA and SCDHEC plan to propose modifications to the 1989 ROD to include a remedy that would more effectively and efficiently restore the contaminated aquifer for future use. At that time, Vinyl Chloride will be included as a proposed modification to the 1989 ROD as well. In the interim, Vinyl Chloride is included in the monitoring program.

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5.2 Determine the appropriate I Cs for the Site

The current owner of the Site property is the defunct Carolawn Company, Inc. Therefore, the EPA has not identified a viable property owner for the Site willing to execute and record I Cs. The four residences who used private wells were provided an alternative water source in 1985 and connected to the Chester MSD. There are no known current or planned uses of groundwater as a drinking water source or any other source on or in the vicinity of the Site.

5.3 Evaluate available groundwater treatment technologies to restore the contaminated aquifer

In August 2010, the CSC conducted a SVE pilot study to collect data to evaluate the potential use of SVE as an IRM as part of an overall groundwater remediation strategy. The results of the SVE study indicated SVE as a feasible approach to reduce VOC mass in the subsurface (vadose zone) which could result in reduced VOC concentrations in groundwater. Construction of the SVE system was completed in January 2012. Operation of the SVE system has reduced VOC mass from the subsurface and is expected to reduce the flux of voes to groundwater which will allow groundwater concentrations to decline over time. VOC mass removal from the SVE system will continue to be monitored to assess the impact of the SVE System on groundwater conditions. In addition, this performance data will be used to support completion of the FFS which could lead to modifying the 1989 ROD.

5.4 Place a deed notice acknowledging the potential risk, if any of soil vapor migration

EPA has not placed a deed notice acknowledging the potential risk, if any, of soil vapor migration through future inhabitable structures on the deed of properties within the contaminated area of the plume. There are no inhabitable structures on the Caro lawn Property. At the time of the third FYR, one inhabitable structure was present south of the Site. Based on the results of a Tier 2 generic Vapor Intrusion (VI) pathway screening and a Site-Specific VI pathway evaluation, the design of the structure did not provide conditions that allow the migration of potential soil vapors into the building. Therefore, no further VI evaluations were required unless the future land use changes. In addition, the land use has change and there are no longer inhabitable structures located south of the Site.

6.0 Five-Year Review Process

6.1 Administrative Components

The EPA in conjunction with SCDHEC, conducted the FYR of the remedy implemented at the Site. The EPA initiated the fourth Five-Year Review on March 7, 2013. Parties who provided input and review of the data used for the Five-Year Review included:

EPA Region 4 • Yvonne Jones, Remedial Project Manager • Tonya Whitsett, Public Affairs Specialist • Tim Frederick, Toxicologist • Bill Osteen, Hydrogeologist • Christopher Cole, Attorney

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SCDHEC • Charles Williams, Project Manager • Greg Cassidy, Project Manager

Representatives of Carol awn Steering Committee (CSC) • Todd Hagemeyer, Associate, Geosyntec • Jim Deitsch, Senior Engineer, Geosyntec • Jeffrey Ahrens, Project Engineer, Geosyntec

This Five-Year Review includes:

• Community notification, • Document review, • Data collection and review, • Site Inspection, • Local interviews, and • FYR Report development and review.

6.2 Community Involvement

Activities conducted in an effort to encourage community involvement for the Carolawn Superfund Site's Five-Year Review commenced in February of2013. The EPA placed a public notice in The Lancaster News and additionally hosted a community meeting the following month. The newspaper notice announced the commencement and anticipated month of completion of the Fourth, Five-Year Review process for the Site, provided contact information for Remedial Project Manager Yvonne Jones and Community Involvement Coordinator Tonya Whitsett, provided information on the report's availability and invited community participation via the offering of interviews. Copies of the newspaper notice and the slide presentation reviewed at the March meeting, are available in Appendix B. There were no phone calls received in response to the placement of the newspaper notice. A question and answer session held at the public meeting authenticates the continuation of a creditable rapport between the agency and community.

The FYR Report will be made available to the public upon finalization. Copies of this document will be placed in the designated site repository located at the following locations:

• The EPA Records Center, l l 1h Floor, 61 Forsyth Street, SW, Atlanta, GA 30303

• The Lancaster County Library, 313 South White Street, Lancaster, SC 29720

6.3 Document Review

This FYR included a review of relevant, site-related documents including the RODs for OU-1 and OU-2, the previous FYR, and monitoring data. A complete list of the documents reviewed can be found in Appendix A.

ARAR Compliance Review As discussed in Section 4.1.2, chemical-specific ARARs are specific numerical quantity restrictions on individually listed contaminants in specific media. The remedy selected for this

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Site was designed to meet or exceed all chemical-specific ARARs and meet location-and action­specific ARARs. A summary of the ARARs evaluated in the ROD for OU-I (1989 ROD) is provided in Table 4.

Surface Water in Fishing Creek For surface water, the A WQC for the COCs were established as the surface water cleanup goals in the 1989 ROD. However, the ROD stated that "the surface water analyses conducted during the RI indicates that the discharge ofgroundwater to Fishing Creek has not had a measurable impact on the water quality in Fishing Creek.·· and "even under 7Q10flow conditions, the rate and level ofdischarge ofcontaminants with the groundwater into Fishing Creek will not surpass the Ambient Water Quality Criteria (A WQC) for the contaminants ofconcern." Therefore, the 1989 ROD concluded that the Site presented no unacceptable risk to Fishing Creek, even under pre-remedial conditions.

Since the issuance of the 1989 ROD, in October 1997, the CSC' s benthic study of Fishing Creek (near the Site), conducted by Shealy Environmental Services, Inc., determined that the Site NPDES discharge had not had any impact on benthic community in Fishing Creek, and the test demonstrated that the treated groundwater discharge was not toxic. In addition, laboratory analysis of the effluent water (required by the NPDES pem1it) collected periodically during operation of the GWETS, confirmed that VOCs were completely treated by the GWETS to non­detectable levels prior to discharge to Fishing Creek.

Groundwater The "cleanup goals" for groundwater are presented in Table 23 of the 1989 ROD and Table 2 in this FYR report. The groundwater remedial goals selected were based upon EPA's MCLs or proposed MC Ls with two exceptions, acetone and 1, 1-dichloroethane, which do not have MCLs. As such, the following is a comparison of the 1989 MCLs to the current MCL standards:

e The "proposed" MCLs for cis- and trans-1,2-dichloroethene have been accepted as proposed. Therefore, the values in the 1989 ROD reflect the current MCLs.

• There have been no changes in the MCLs for 1, 1-dichloroethene, 1, 1, I-trichloroethane, and trichloroethene. Therefore, the 1989 ROD is consistent with the current MCLs for these contaminants.

e The proposed MCL for lead presented in the 1989 ROD is 5 µg/L. This value was not adopted as an MCL. The current MCL listing includes an action level for lead, 15 µg/L that is based upon "a Treatment Technique that requires systems to control the corrosiveness of their water." The lead clean-up goal presented in the 1989 ROD is lower than the lead action level and is therefore more conservative.

The clean-up goal for acetone presented in the 1989 ROD, 700 ~tg/L, is based upon a "lifetime health advisory value." Acetone is not included on the most current (2012) listing of Drinking Water Health Advisories. The current Regional Screening Value for acetone is 12,000 µg/L. The cleanup goal proposed in the 1989 ROD is lower than the current screening value and is therefore a conservative goal.

o A cleanup goal for 1, 1-dichloroethane is not presented in the 1989 ROD. A footnote says: "No firm cleanup criteria has been established but it is assumed that due to I, I­

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0

dichloroethane similar chemical/physical characteristics with the other contaminants present, the levels will decrease proportionally along with the other contaminants." For comparison purposes, the current tap water Regional Screening Value for 1, 1-dichloroethane is 2.4 ~tg/L. The Regional Screening Value or a site-specific risk based cleanup goal could be used as a cleanup goal for 1, 1-dichloroethane.

The review of ARARs for the groundwater contaminants suggests that federal and state standards (i.e, MC Ls) for cis- and trans-1,2-dichloroethene, 1, 1-dichloroethene, 1, 1, I-trichloroethane, and trichloroethene remain the same. The cleanup goals proposed in the 1989 ROD for lead, acetone and 1, 1-dichloroethane are lower than the current screening value and are therefore conservative cleanup goals. Therefore, the cleanup goals established in the 1989 ROD are protective of human health and the environment.

The analysis of the 1989 and current MeLs is also set forth in Table 5.

Institutional Controls Review

The EPA conducted a review of institutional controls at the Site and surrounding properties. Institutional controls are needed on the earolawn property and may be needed on the surrounding properties to restrict groundwater use. The 1989 ROD required appropriate institutional controls at the Site, but institutional controls have not been implemented for the Site or the surrounding properties due to the lack of a viable property owner willing to execute and record ICs. Additionally, residences and businesses near the Site obtain their drinking water from the public water supply. Table 6 presents property information for the earolawn property and institutional controls needed. Further evaluation of the residential properties ( 146-00-00-016-000 and 146-00-00-03 7-000) near the Caro lawn Property is required to determine if institutional controls are needed. Figure 5 shows the location of the earolawn Property (including the Site) and the surrounding parcels in relation to the Site.

A summary of the deed record for the Caro lawn Property is presented in Table 9.

6.4 Data Review

6.4.1 Results of the GWETS Evaluation and EISB Pilot Study

Operation of the GWETS was discontinued in July 2004. The EISB Pilot Study was discontinued following the April 2010 injection well rehabilitation and dual phase extraction tests. However groundwater monitoring has continued to present. 4 years after G WETS shutdown and EISB implementation, the VOC distribution and plume extent in the Site groundwater did not significantly change and the areas with the greatest voe concentrations remained stable. The results of the GWETS Evaluation and the EISB are included in the third FYR.

6.4.2 Status of the Soil Vapor Extraction System Pilot Study

Site-Wide Vapor Sampling Results

Construction of the SVE system was completed in January 2012 for the purpose ofreipoving chlorinated voes from the subsurface (vadose zone). The individual VOC results for December 2011, September 2012 and April 2013 site-wide vapor sampling event are presented in Table 7.

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Table 8 presents the total VOe concentrations for the vapor monitoring (VM) wells for the three sampling events conducted. The following observations are made:

• The maximum total voe vapor concentration decreased from 342. 76 parts per million per volume (ppmv) (VM-15 on 16 December 2011) to 10.28 ppmv (VM-10 on 25 April 2013 );

• The site-wide average total voe vapor concentration decreased from 43.3 ppmv to 2.5 ppmv from December 2011 to April 2013, representing a 94.3% reduction;

• The spatial distribution of vapor wells with increasing and decreasing total VOe concentrations over multiple periods is highlighted in Figure 6. Total VOe vapor concentrations decreased at 12 vapor wells (VM-4 through VM-8, VM-12, and VM-14 through VM-19), remained constant at one vapor well (VM-1), and increased at five vapor wells (VM-2, VM-9 through VM-11, and VM-13).

The lower VOe results measured in April 2013 compared to previous site-wide sampling performed in December 2011 and September 2012 indicate significant progress has been made to remove voes from the vadose zone.

Mass Removal Estimation

The SVE effluent was sampled weekly for the first eight weeks of operation to estimate the mass ofVOes removed from the subsurface. The mass of voes removed was calculated by estimating a flow rate based on the system vacuum and the blower performance curve multiplied by the measured concentrations of voes based on laboratory analysis. The mass estimations were linearly interpolated between sampling events to calculate average daily mass removal rates. After week eight, the effluent sampling frequency was reduced to monthly.

Overall, approximately 155 lbs of voes have been removed during the 71 weeks of SVE system operation (Figure 7). The mass removal rate was 10.3 lb/day at startup and was approximately 0.039 lbs/day leading up to Week 71 (June 4, 2013), at which time the system was shut down for a one-month equilibration period.

In March 2013, the system was shut down for a month equilibration period. On 25 April 2013, the system was restarted and effluent samples were collected 1 hour, 21.5 hours, 7 days, and 40 days after vapor extraction was initiated. The effluent sample collected 21.5 hours after system restart had a total voe concentration of 0. 78 ppmv, indicating that the mass removal rate was relatively constant during the first day of operation. The effluent samples collected 7 and 40 days after restart were 0.49 and 0.32 ppmv, respectively, showing a gradual decrease in the mass removal rate during the month following system restart.

The estimated mass removal rates using the April and June 2013 effluent data are 0.087 and 0.039 lbs/day, respectively. The June mass removal rate is consistent with the mass removal rate observed from August 2012 to March 2013 (excluding system shutdown data). The total VOe mass removed from 25 April 2013 to 4 June 2013 is estimated to be approximately 2.2 lbs.

The steady removal rate suggests that there is value in continuing to operate the SVE system and that less frequent sampling and monitoring is warranted.

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6.4.3 Post-GWETS Shutdown VOC Concentrations/Plume Conditions

The groundwater VOC data collected through March 2013 indicate that the overall VOC plume remains relatively stable while overall VOC concentrations are showing decreasing trends. For example, trichloroethene (TCE) concentrations in MW-6 (representing the highest TCE concentrations detected at the Site) have shown a steady decline and a 30% reduction in dissolved-phase TCE from the period of March 2011 through March 2013. Additionally, TCE concentrations in downgradient wells located in the vicinity of Fishing Creek (MW-I OA, MW­!OB, MW-I IA and MW-1 IB) show general stable conditions with decreasing trends with some seasonal fluctuations during the last five years of groundwater monitoring. Taken collectively, SVE system operational data and groundwater plume monitoring suggest that Site VOC conditions are improving, source area mass is reducing, and the VOC groundwater plume is generally stable and decreasing. A summary of the VOC concentrations detected m groundwater between 2009 and 2013 is depicted on Figure 8.

6.4.4 Vapor Intrusion Pathway Evaluation

During the third FYR, OB&G conducted a VI Pathway evaluation. At the time of the third FYR, one inhabitable structure was present south of the Site (Furr and Lambert property). Based on the results of a Tier 2 generic Vapor Intrusion (VI) pathway screening and a Site-Specific VI pathway evaluation, the design of the structure did not provide conditions that allow the migration of potential soil vapors into the building. Furthermore, during the fourth FYR, there are no inhabitable structures on the Carolawn Property or on the Furr and Lambert property. Therefore, no further VI evaluations are required unless the future land use changes.

6.5 Site Inspection

The site inspection/interview for this FYR was conducted on March 7, 2013, by Yvonne Jones, the EPA Region 4; Charles Williams, SCDHEC; and Brian Jacobson and David Hanley, Geosyntec. Although, the G WETS is not currently operating, the purpose of the inspection was to take photographs and assess the condition of the GWETS, the SVE System, monitoring, injection and extraction wells and fences. During the EISB pilot study, the pump and piping were removed from several extraction wells and properly stored. As noted in the Action Plan, the pump removal and system decommissioning was conducted in a manner such that the GWETS can be operational within a timely manner, in the unexpected event that resumption of operation 1s necessary.

During the site inspection, the groundwater monitoring wells, injection wells and the vapor monitoring wells were locked and appeared to be in good condition. In addition, the wells were well marked and secured. The entrances to the Site and the GWETS were fenced and locked and had appropriate signage.

In general, the site grounds were neat and orderly. The roads and trails within the Site were passable. The GWETS building was secured. Inside the building was a record log of activities at the Site, as well as Material Safety Data Sheets (MSDSs), O&M Plan and health and safety plan.

The site inspection form is included in Appendix E.

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6.6 Site Interviews

Yvonne Jones of the EPA and Charles Williams of SCDHEC conducted an interview at the Site with Brian Jacobson and David Hanley (Geosyntec). In general, all the work conducted previously by OB&G and currently by Geosyntec has been performed without conflict and in compliance with the legal orders arranged for the RD, RA & OM&M and Pilot Study activities. SVE Pilot Study, current uses of the Site, groundwater contamination and other system optimization activities were discussed. Additional discussions and correspondence with Todd Hagemeyer and Jeffrey Ahrens (Geosyntec) occurred throughout this review period. All parties were readily forthcoming with all pertinent documentation needed for the five-year review process.

Activities to engage the community in the Five-Year Review process commenced with a notice placed in The Lancaster News on Friday, February 22, 2013. The notice announced the FYR and the anticipated completion in August 2013, invited comments and provided point-of-contact information for the EPA Superfund Site Remedial Program Manager and Community Involvement Coordinator while noting the availability and location of the report once made available. A copy of the notice, as well as the printed slides from a presentation given at a community meeting held on March 7, 2013, are provided in Appendix B of this report.

In response to the publishing of the public notice and an invitation sent to the Site's email contacts, there were no requests from residents to serve as interviewees. However, three residents were receptive of requests for interviews via telephone. The following questions were considered by the interviewees:

Are you aware ofthe forrner environmental issues at the Site and the cleanup activities that have taken place to date?

What is your overall impression ofthe project; including cleanup, maintenance, and reuse activities (as appropriate)?

What have been the effects ofthis Site on the surrounding community. ({any?

Have there been any problems with unusual or unexpected activities at the Site. such as emergency response. vandalisrn or trespassing?

Has EPA kept involved parties and surrounding neighbors informed ofactivities at the Site? How can EPA best provide site-related information in the future?

Do you own a private well in addition to or instead ofaccessing city/municipal water supplies? Ifso, for what purpose(s) is your private well used?

Do you have any comments. suggestions or recommendations regarding any aspects ofthe project?

In brief summary, the Caro lawn Site is in a rural area with no residential housing near the Site. Although a resident reported the use of a well per one of the questions above, there are no reports of residential well usage on the Site or within the contaminated area of the plume. Another

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resident inquired as to whether there had been any incidents of theft on the Site due to concerns about copper theft in the area. EPA responded in the negative.

Community interest in the Site has waned since the early activism of the Community Advisory Group which was formed early in the Site's history, however agency representatives continue efforts to keep the community informed and apprised of any new developments or changes in status. In response to interviewees concerns about decreasing interest, EPA has proposed the purchase of a new mailing list to merge with the existing contacts and via which new residents will be notified of future activities.

7.0 Technical Assessment

7.1 Question A: Is the remedy functioning as intended by the decision documents?

Yes, the review of documents, ARARs, risk assumptions, and the results of the site inspection indicate that the remedy was functioning as intended by the 1989 ROD prior to shutdown of the GWETS. The GWETS operated from October 1996 through July 19, 2004. During operations of the GWETs, the air stripper effectively reduced the concentration of VOCs to levels less than the detection limit. Accordingly, effluent discharges of VOCs were below the Site's NPDES permit levels.

The operation of the G WETS did satisfy the RA Os through ~he reduction of contaminant mobility and volume in the aquifer via groundwater extraction and air stripping to remove VOCs, prior to discharge to Fishing Creek. However, the GWETS extraction rates and volumes were significantly limited due to groundwater drawdown below fractures in the extraction wells in the low yielding granodiorite aquifer. Furthermore, the ROD estimated that the remediation objective (MCLs) would be attained within 10 years following commissioning of the GWETS. However, it is estimated that the GWETS would have to operate for at least an additional 62 years to achieve MCLs due primarily to the low yield of the bedrock fornrntion. ­

In response to the limitations of the GWETS remedy, EISB treatment of groundwater was implemented as a 'pilot study' in an effort to accelerate the reduction in the VOC concentrations in groundwater. The GWETS was shutdown by OB&G on July 19, 2004 with approval from the EPA and SCDHEC. Upon review of the results of the GWETS optimization study and EISB treatment of groundwater, the EPA recommended further evaluation of available groundwater treatment technologies. Such evaluations would assess whether technologies other than GWETS would more effectively and efficiently restore the contaminated aquifer for future use.

In March 2009, the EPA issued a Modified Unilateral Administrative Order (UAO) to the CSC which required a Focused Feasibility Study (FFS) to identify a groundwater remedy more favorable than the GWETS. The CSC submitted a draft FFS to the EPA in January 2010 and subsequently met with EPA to discuss the same. In August 2010, the CSC conducted a soil vapor extraction (SVE) 'pilot study' to collect data to evaluate the potential use of SVE as an Interim Remedial Measure (IRM) as part of an overall groundwater remediation strategy. The results of the SVE study indicated SVE as a feasible approach to reduce VOC mass in the subsurface (vadose zone) which could result in reduced VOC concentrations in groundwater. Following discussions with SCDHEC, the CSC and the Community Advisory Group (CAG), the EPA issued the Notice to Proceed with the remedial design and construction of the SVE system. Construction of the SVE system was completed in January 2012. Operation of the SVE system

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has reduced voe mass from the subsurface and is expected to reduce the flux of voes to groundwater which will allow groundwater concentrations to decline over time. Approximately 155 lbs of VOCs have been removed during seventeen months of SYE system operation. In comparison, the GWETS extracted 35 lbs of VOCs from the groundwater plume during 7 years of operation. SVE system operational data and groundwater plume monitoring suggest VOC conditions are improving, source area mass is reducing, and the VOC groundwater plume is generally stable and decreasing. VOC mass removal from the SVE system will continue to be monitored to assess the impact of the SVE System on groundwater conditions.

Although the 1989 ROD required ICs, ICs have not been implemented at the Site due to the lack of a viable property owner willing to execute and record I Cs. The defunct Caro lawn Company is listed as the property owner. Therefore, the EPA has not identified a property owner for the Site. The Site is currently not in use. There are currently no residential well users on the Site or within the contaminated area of the plume area. The four residences closest to the Site who used private wells were provided an alternative water source in 1985 and connected to the Chester MSD. Moreover, SCDHEC prohibits the installation of any future groundwater use wells unless an application is first filed and approved by SCDHEC. This process may essentially eliminate the potential for future groundwater use in the vicinity of the Site. However, in order for the remedy to remain protective in the long term until ARARs or risk-based performance standards specified in the 1989 ROD are achieved, ICs should be implemented at the Site to restrict the groundwater use at the Site on all properties where contamination from the Site has spread above cleanup goals specified in the 1989 ROD provided a viable property owner exists willing to execute and record ICs.

7.2 Question B: Are the exposure assumptions, toxicity data, deanup leve!s, and remedial action objectives (RAOs) used at the tnme of the remedy selection still valid?

Yes, the exposure assumptions, toxicity data, cleanup levels, and remedial action objectives (RA Os) used at the time of the remedy selection are still valid.

The environmental data presented in the tables of the RI for OU-1 and OU-2 was reviewed. The standard practice at the time that the Public Health Evaluation was conducted included the selection of "indicator chemicals." The Public Health Evaluation determined that groundwater was the only media of concern and decided to carry all detected groundwater contaminants forward for additional evaluation. Since screening was not conducted to pare down the list of contaminants carried forward for quantitative risk evaluation, no contaminants were eliminated from consideration that would have been carried forward using current screening values.·

All of the detected contaminants were carried forward for quantitative evaluation, and each has a clean-up goal presented in the 1989 ROD. The current sampling includes analyses, data presentation, and screening of a range of contaminants beyond those specified in the 1989 ROD. It appears that all potential contaminants of concern continue to be properly evaluated in site documents.

The conceptual site model presented in the RI and BRA reports were reviewed to ensure that all potential exposure pathways had been evaluated and considered in the development of the RODs for OU-I and OU-2.

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While the passive VI pathway was not considered in 1989 ROD and 1995 ROD, in April 2008 a memorandum evaluating the potential risks of the VI pathway was prepared by OB&G on behalf of the CSC. The memorandum determined that currently there are no complete exposure pathways for the VI pathway and therefore did not evaluate the potential risks. Furthermore, during the fourth FYR, there are no inhabitable structures on the Carolawn Property or the Furr and Lambert property This approach is consistent with Risk Assessment Guidance for Superfund (RAGS) and the Office of Solid Waste and Emergency Response (OSWER) draft guidance for evaluating vapor intrusion. However, if new inhabitable structures are constructed, the VI pathway may need to be re-evaluated.

The review of ARARs for the groundwater contaminants in Table 5 suggests that federal and state standards (i.e., MC Ls) for cis- and /rans-1,2-dichloroethene, l, 1-dichloroethene, 1, 1, 1­trichloroetheane, and trichloroethene remain the same. The cleanup goals proposed in the 1989 ROD for lead, acetone and 1, 1-dichloroethane are lower than the current screening value and are therefore conservatives cleanup goals. Therefore, the cleanup goals set in the 1989 ROD are protective of human health and the environment.

The 1989 ROD has not been modified to include Vinyl Chloride, 1,2-dichloroethane and tetrachloroethene as a perfomrnnce measure. However, Vinyl Chloride, 1,2-dichloroethane and tetrachloroethene are included in the monitoring program.

Physical site conditions have not changed in any way that could affect the protectiveness of the remedy.

Toxicity Factors for contaminants of concern for human and ecological health have not changed in any way that could affect the protectiveness of the remedy. Therefore, the current remedies established for the Carolawn Site are protective.

7.3 Question C: Has any other information come to light that could call into question the protectiveness of the remedy?

As discussed above in Sections 7.1 and 7.2, the selected remedy for groundwater was shutdown in July 2004, and an evaluation of other remedial technologies is ongoing. There are currently no residential well users on the Site or within the contaminated area of the plume and the four residences closest to the Site were connected to the Chester MSD. However, the evaluation of other remedial technologies should continue to determining the feasibility of accelerating the reduction in the voe concentrations in groundwater.

7.4 Technical Assessment Sum~ary

The review of documents, ARA Rs, risk assumptions, and the results of the site inspection indicate that the remedy was functioning as intended by the 1989 ROD. However, the ROD estimated that the remediation objective (MCLs) would be attained within l 0 years following commissioning of the GWETS. It was estimated that the GWETS would have to operate an estimated additional 62 years to achieve MC Ls due primarily to the low yield of the bedrock formation.

In response to the limitations of the GWETS remedy, EISB and SVE treatment of groundwater were implemented as 'pilot studies' in and an effort to accelerate the reduction in the VOC

42

concentrations in groundwater. The GWETS was shut down by OB&G on July 19, 2004 with approval from the EPA and SCDHEC. Given the perfom1ance of the GWETS and the EISB treatment of groundwater, the EPA's conclusion from this five-year review is to continue operation of the SYE System as well as evaluate available technologies to achieve faster performance of the remedial action objectives.

Institutional controls are needed on the Carolawn property and may be needed on the surrounding properties to restrict groundwater use. The 1989 ROD required appropriate institutional controls at the Site, but institutional controls have not been implemented for the Site or the surrounding properties due to the lack of a viable property owner willing to execute and record ICs. Further evaluation of the residential properties (146-00-00-016-000 and 146-00-00­03 7-000) near the Caro lawn Property is required to determine if institutional controls are needed. The EPA should continue to work with CSC, SCDHEC and the landowners to implement ICs.

'

8.0 Issues

Table 10 summarizes the issues generated during this five-year review.

Table 10: Issues for the Carolawn Site

Affects Current Affects Future Issue Protectiveness Protectiveness

(Y/N) (YIN) The 1989 ROD did not include vinyl chloride, 1,2-dichloroethane and No Yes tetrachloroethene in the list of COCs with cleanup goals. The 1989 ROD required !Cs. !Cs are necessary because there are no No Yes restrictions on the Site to prevent exposure to contaminated groundwater other than SCDHEC's well permit requirements for new installations. !Cs may be needed on residential properties adjacent to the Site. - No Yes

The remedy was functioning as intended by the 1989 ROD. The 1989 No No ROD estimated 10 years to achieve MC Ls. However, it was recently estimated that the GWETS would have to opera_te an estimated additional 62 years to achieve MCLs due primarily to the low yield of the bedrock

fonnation.

43

9.0 Recommendations and Follow-up Actu~ms

Table 11 provides recommendations to address the current issues at the Carolawn Site.

Table 11: Recommendations to Address Current Issues at Carolawn Site

Issue

The 1989 ROD did not include vinyl chloride, l ,2-dichloroethane and tetrachloroethene in the list ofCOCs with cleanup goals.

The 1989 ROD required !Cs. !Cs restricting groundwater use may be necessary because there are no restrictions in place to prevent exposure to contaminated groundwater trom the Site that exists above cleanup goals specified in the 1989 ROD, other than SCDHEC's well permit requirements.

ICs may be needed on residential properties adjacent to the Site.

The remedy was functioning as intended by the 1989 ROD. The 1989 ROD estimated l 0 years to achieve MCLs. However, it is estimated that the GWETS would have to operate an estimated additional 62 years to achieve MC Ls due primarily to the low yield of the bedrock formation.

Recommendations/ Follow-Up Actions

An appropriate decision document should be prepared to add vinyl chloride, 1,2­dichloroethane and tetrachloroethene to the list of cleanup goals to be addressed at this Site. The EPA, SCDHEC and the CSC should work with the Site Property owners to detennine the appropriate !Cs at the Carolawn Site to prevent exposure to contaminated groundwater trom the Site that exists above cleanup goals specified in the 1989 ROD for execution by a viable property owner willing to execute and record such !Cs. Evaluate the need for !Cs on residential properties adjacent to the Site. Continue to evaluate available groundwater treatment technologies to detennine whether such technologies would be more effective than the GWETS in efficiently restoring the contaminated aquifer. If another alternative is preferred, a decision document will be issued for the Caro lawn Site.

Party Responsible

EPA and SCDHEC

csc

CSC,EPA and

SCDHEC

csc

Oversight Agency

EPA and SCDHEC

EPA and SCDHEC

EPA and SCDHEC

EPA and SCDHEC

Affects Protectiveness?

Milestone Date (Yes or No)

Current Future 12/30/2015 No Yes

0913012017 No Yes Basis:

evaluation of the effect of

SVE !RM is on­going

0913012015 No Yes

12/30/2015 No No

44

10.0 Protectiveness Statement

The remedy at the Carolawn Site is protective in the short term since there is no complete exposure pathway to contaminated groundwater and the groundwater extraction and treatment remedy was functioning as intended by the 1989 ROD.

For the remedy to be protective in the long tem1, the following actions should occur:

• An appropriate decision document should be prepared to add vinyl chloride, 1,2­dichloroethane and tetrachloroethene to the list of cleanup goals to be addressed at this Site.

• Detem1ine the appropriate institutional controls to restrict groundwater use at the Site.

• Evaluate the need for ICs restricting groundwater use on residential properties adjacent to the Site.

• Continue to evaluate available groundwater treatment technologies to determine whether such technologies would be more effective than the GWETS in efficiently restoring the contaminated aquifer. If another alternative is preferred, a decision document will be issued for the Carolawn Site.

11.0 Next Review

The next five-year review for the Carolawn Site is required five years from the completion date of this review.

45

APPENDIX A

DOCUMENTS REVIEWED

----------------------------------------------- ------------- ---

Appendix A Documents Reviewed

Carolawn Site .. Fourth Five-Year Review

"Administrative Order of Consent for Removal Action, Carolawn, Fort Lawn, South Carolina," USEPA Region 4. (September 11, 1985)

"Partial Consent Decree for Remedial Investigation/Feasibility Study, Carolawn, Fort Lawn, South Carolina," USEPA Region 4. (August 29, 1985)

"Final Report - Remedial Investigation, .. Carolawn Site, Fort Lawn, South Carolina,'' Conestoga-Rovers & Associates, for the Caro lawn Steering Committee. (November 1989)

"Record of Decision, Carolawn (Operable Unit One) Site, (USEPA ID: SCD9805583 I 6), Fort Lawn, South Carolina," United States Environmental Protection Agency, Region 4. (September 27, 1989)

"Partial Consent Decree for Remedial Design and Construction, Carolawn, Fort Lawn, South Carolina," US EPA Region 4. (December 2, 1991)

"Final Report - Remedial Investigation, Carolawn (Operable Unit Two) Site, Fort Lawn, South Carolina," United States Environmental Protection Agency, Region 4. (July 11, 1995)

"Final Report - Baseline Risk Assessment, Carolawn (Operable Unit Two) Site, Fort Lawn, South Carolina," Black & Veatch Waste Science, Inc., for the United States Environmental Protection Agency, Region 4. (July 12, 1995) ­

"Record of Decision, Carolawn Operable Unit Two Site, Fort Lawn, South Carolina," United States Environmental Protection Agency, Region 4. (September 1995)

"Operation and Maintenance Manual, Carolawn, Fort Lawn, South Carolina," Conestoga-Rovers & Associates, for the Carolawn Steering Committee. (August 30, 1996), Revision 1 (February 25, 1997)

"Unilateral Administrative Order for Operation and Maintenance and Performance Monitoring, Carolawn, Fort Lawn, South Carolina," USEPA Region 4. (July 28, 1997)

"Operation and Maintenance Plan, Carolawn, Fort Lawn, South Carolina," Conestoga-Rovers & Associates, for the Carolawn Steering Committee. (October 31, 1996), Revision l (July 14, 1997)

"Remediation System Evaluation Report and Action Plan, Carolawn Superfund Site, Fort Lawn, South Carolina, (USEPA ID: SCD980558316)," O'Brien & Gere Engineers, Inc., Prepared for: Carolawn Steering Committee. (August 2004)

"EISB Progress Report (Post Injection Monitoring Results), Carolawn Superfund Site, Fort Lawn, South Carolina, (USEPA ID: SCD980558316),'; O'Brien & Gere Engineers, Inc., Prepared for: Carolawn Steering Committee. (February 2008)

"Remedial Evaluation Report, Carolawn Superfund Site, Fort Lawn, South Carolina, (USEPA ID: SCD980558316)," O'Brien & Gere Engineers, Inc., Prepared for: Carolawn Steering Committee. (April 2008)

Memorandum from William Shew, O'Brien & Gere Engineers, Inc., to Yvonne 0. Jones, US EPA Region 4, Carolawn Site - Vapor Intrusion Pathway .. (April I, 2008)

Memorandum from Tim Frederick, USEPA Region 4 to Yvonne 0. Jones, USEPA Region 4, Human Health Risk Assessment Review for the Five-Year Review of the Caro lawn Site. (July 21, 2008)

"Third Five-Year Report for the Caro lawn Superfund Site, Fort Lawn, Chester County, South Carolina, " South Carolina Department of Health and Environmental Control, for the United States Environmental Protection Agency, Region 4," (September 25, 2008)

"Modified Unilateral Administrative Order for Operation and Maintenance, Performance Monitoring, and Focused Feasibility Study, Carolawn, Fort Lawn, South Carolina," USEPA Region 4. (March 10, 2009)

"Results from Injection Well Rehabilitation and Dual Phase Extract.ion Tests, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Carolawn Steering Committee. (May 4, 2010)

"Plan to Conduct Pre-Design Soil Vapor Extraction Tests, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Carolawn Steering Committee. (July 21, 2010)

"Results of Soil Vapor Extraction Testing, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Caro lawn Steering Committee. (November 1, 2010)

"Results from Injection Well Rehabilitation and Dual Phase Extraction Tests, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Carolawn Steering Committee. (May 4, 2010)

"Soil Vapor Extraction System Design, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Caro lawn Steering Committee. (November 2011)

"Biennial Groundwater Monitoring Report, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Caro lawn Steering Committee. (March 5, 2012)

"Soil Vapor Extraction System Construction Completion Report, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Carolawn Steering Committee. (March 2012)

"SVE System Report for March 2012, Caro lawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Carolawn Steering Committee. (April 27, 20.12)

"SVE System Report for May 2012, Caro lawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Caro lawn Steering Committee. (July 13, 2012)

"SVE System Report for June 2012, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Caro lawn Steering Committee. (July 30, 2012)

2

"SVE System Report for August 20 I 2, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Caro lawn Steering Committee. (October I, 20 I 2)

"SVE System Report for September and October 2012, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Carolawn Steering Committee. (November 14, 2012)

"SVE System Report - 7 November 2012 Through 5 December 2012, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Caro lawn Steering Committee. (January 30, 20 I 3)

"Notification of Groundwater Sampling Event, Carolawn NPL Site, 5093 Morrison Rd., Fort Lawn, SC," Geosyntec Consultants, Prepared for: Caro lawn Steering Committee. (January 30, 20 I 3)

"SVE System Report - 6 December 20 I 2 Through 31 March 2013, Caro lawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Carolawn Steering Committee. (June 17, 2013)

"SVE System Report - 1 April 20 I 3 Through 1 June 2013, Caro lawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Carolawn Steering-Committee. (August 13, 2013)

"EMAIL - March 2013 Groundwater Sampling Data, Tables and Figures, Carolawn Superfund Site, Fort Lawn, South Carolina," Geosyntec Consultants, Prepared for: Carolawn Steering Committee. (August 21, 2013)

3

APPENDIXB COMMUNITY RELATIONS

~~l:l>St.4.>; ~ ~IS'. ~.

f ~~ :11~111

\;~(~~jl THE UNITED STATES

ENVIRONMENTAL PROTECTION AGENCY

Announces the

Fourth Five-Year Review For the

Carolawn, Inc. Superfund Site

rite U.S. Environmental Protection Agency (EPA) and the South Carolina Department of Health and Environmental Control (SCDHEC) are conducting the Fourth Five-Year Review of tire Carolawn Site located in Fort Lawn, Chester County, South Carolina. The purpose of this review is to evaluate the implementation ~nd performance of the remedy in order to determine if the i:emedy continues to be protective of human health and the environment.

In September 1989, EPA selected groundwater extraction and treatment as the remedy to address groundwater contamination at the Carolawo site. After additional investigations, in April 1994, EPA determined no additional response actions were required for the soil, surface water and the sediments at the Carolawn Site.

As a component of the Five-Year Review, EPA conducts interviews with nearby busim:sses, residents, local officials, state officials, and others to obtain their opinions on the cleanup process. The community can contribute during this Fi'!e-Ycar Review by providing comments or questions. Community members who have questions about the site or the Five-Year Review process, or who would like to participate in a community interview, are asked to contact a site team representative.

Community Engagement: Tonya Whitsett, EPA Community Involvement Coordinator at (404) 562-8633 Technical Inquiries: Yvonne Jones, EPA Remedial Project Manager at (404) 562­8793

EPA plans to complete the Five-Year Review for the Carolawn Site by August 2013. Upon completion, a copy of the Five-Year Review report will be placed in the Information Repository files located in the EPA Record Center, 11th Floor, 61 Forsyth Street, SW, Atlanta, GA 30303, and at the Lancaster County Library, 31 l South White Street, Lancaster, SC 29720. Additional site information is available at the local document repository and online at: http://www.epa.gov/region4/superfund/ sites/npl/southcarolina/carolwsc.html

CAROLAWN SUPRFlJND SlTE

MARCH 2013 COMMUNYTY ADV~SORY GROUP MEET:n:NG

SLIDE PRESENTAl'ION

• CAROLAWN COMMUNITY ADVISORY GROUP MEETING

CAROLAWN SUPERFUNO SITE FORT LAWN, CHESTER COUNTY, SOUTH CAROLINA

March 7, 2013

•

•

SITE BACKGBOUNp

• The 60-acre Caro lawn property was ong1nally used to stora solvent wastes produce1j at other pro0>2ssing facilities.

• A secunty tani::~e enelosi::-s approximately· 3 acres ot tht> Site (0U1). Hc0wever. the w13st and nonh drum aroas are located outside the fenced area (0U2 ).

Between 1970 and 1980. the property· ct1anged cwnership several t1m&s before being abandon.;.d, leavina more than 1,000 li?.a~:1nq tanks and drums of hazardous chemicals. and a lagoc·n tilled with toxic sludge. ­

Between 1981 and 1982, EPA removed over 1,000 drums of hazardous waste and several tons of c.ontaminated soil, and all n'3arby residences WtiP?! prov1d&d an alternative water source.

In May 1985. the Potenually Respons1Dlo Parties (PRPs J •Conducted additional mm oval activities to address contaminated soil and the lagoon areas eon the Site.

Between·1887 and 1989. the PRPs conducted multi-phased Remedial Investigation/Feasibility St'Udy {Rl/FS) activities on OU1

SITE BACKGROUND (can't)

• Thti R l/FS confirmed the pri:-senc8 C•t VO Cs 1n tne groun1Jwater 9)cCeeding the MCLs.

• Record ot Deasion (ROD) tor OU-1 issued in 1989.

• Tne pnmary components of tho 1989 ROD. - Installation of a grouni'Jwattir intEtrctiption and .::i:dra 1:.lion syStEim - C11sposa1 ot two inactiv'3 incinerators and drums - Monitoring groundwater quality - Implementing appropriate Institutional Controls - Close private wells - REicommend addit1i:Jnal fiel•j activities on OU-2 to 1jetermine ttle prBsence or

absence of contamination

In February ·1994. EPA iniaated a Rl/FS on OU2 - torusing pnmanly on the area outside of the fanc8 - soils. surface water and sediment in Fishing Creek.

• On S8~·tt:'mber 21. ·1995. EP.A. issued a ROD f,)r OU2 ..,..,h1Gh seiact.:id a ''n 1rfurther action·' rnrnedy fQr land located 1mmi;idiate1y around the fencad area. Shortly theraafter. the Community Ad'l/isory Group (tl?e first m the RegiJn) was formed.

• Construction required by' the 1 '389 ROD was comploted in 1996.

2

• SITE BACKGROUND fcon'tl

• Three Ave-Year R"""ews were completed (1996. 2003 end 2008)

• ~Second Five-Yeer Review - ~gust 2003 - fXllli!lm OU. to low )'181dng l>edrocl<fonnal>0n. the G'VloETSwould ~ _.ai1on fir

62 years e c:pposed lo 10 ye.rs Bmillllau P'dat Study for Ent.need In-Situ Blodegradat1on !EISB) d gr""'1d ­(injection d N_,,;on Zone> to rNeh MCLs ta.let. Jl.Cy 200ot - M•y 2008 GWETS Shuttloim - CanpAeled EIS8 tnJ"dlcns and egl'tl posl· lnieDllon samplng ewnls. 2008 R!l!lyh 9f EISB PIO! S!JdY Due to the bedrod< fcrmation Ille onterconneCIMIY between Newm.,n Zone aind ground wat.r plume romMi& low. low reduction occurred

• The Third Five-Year Review - September 2006. - GWETS rttmaans cootdown - Grcurd watw C0"1CSltrit1on. ... 1lmbl• - No one 1s eccM"ng lie gro\l'\d wator - All mdent. remain on a pub"' water supply - PftP Group remains cocper.llNe and '"li'1 ng to perfa'm FS to riwill;.te

oeher olt<ornilivl:s to•'*'"""' llilCL$ in len than 02 ~.

• SITE BACKGROUND fcog'tl

- Metch 2009 - EPA •nd tho PRP. 19ood lo amend tho UAO lo dow r... pr_..., ond c~on ol!ho FOCll..d Fndoil;ty Sludy (FFS)

- July 1A 2008- EPA pr........i F1-Year RIWiow F"wuftngdlle>CI mp< lo rho CAG

- Jen,.ry 2010 - Draft FFS prcMdod to EPA ond SCOH EC lbr. ­

- Mitch 2010- EPA and SCOHEC prOYldod con...onh DI eluding tllo nMd for .... 10hobllltilion

- August 2010- Compt.ted ln1ecUon Wtill rehabl1t1tionlc&l•I phaw extrac:tto" (OPE> tnts - FIM1rable Resuls lead to lv;/tlncy ApprOYal to prOC:Nd wlh 1h• Soi Vapor ExWKbon (SVE)

Remedial Ontgn - J1nuaty 2012- Compi.t.d conttruction orth• SVE Syt;tM\ - The SVE. System WH Installed as an Int.rim Remedl.ll M•SUN (I RM) {"ILOT ST\JDY} a 1>9rt

or1n OYlraJI groundvt.t1r rwn1dlmt1on i;trategy. - Approxlm..y 148 lbs or voes were removed withJn the •a weeks d operation of Ii• SVE

5Y•em. During Oi>@f&tion or the GWETs only 1.8 lbs ofVOCs were removedll'I 7 years - The cunnt rreu rw.mov1J rate ll approxm.tety 1 «lbs VOCa per month. - ~tlon offlo SVE ~andMontoring""' ongoing

• 3

-----

• UPDATE:

SITEACTIVITIES/NEXT STEPS

- ,.._ . • ~

...._ ., -­·­4

•

•

'"" r '"°

10 1>0 i• I I

j! ID

1 §a ~

0' "" I "·'1.--·

SVI! SYSTEM voe Rl!COVEJIY C•ro!r#n Sur:.h.ino s-. l"Ott Lawn SOUUt C.rOh•W

Geosyncec" ""'"'""''

• 5

• GENERAL SITE ACTIVITESJNEXT STEPS

OUtstendlna •=es

- lmpromonl rtStrletlOM to pro1ed n. lntogr1ty Of nio rom1dy and 10 prevent expocurt to contamlnillaCI grounci wntar that ~aim om-Jte P'rowt.9 • nollc• en tr.. cteed .-.gerd«lg potential VI issues

- Conduct 'Mlcl-Polnr 1\IOIU111ont ofll>o sve Sy111m b-March. Aptll 20t3.

- Resulb ofltu tvltuatlon wll dk:tC:t raodl'lclllon!' to ttl• sve System .ndlor dUll l•cmotogy.

- When eppropl\ale: Addrt11 ltmltalJons wth the awllab~ technolo91ealadmlnt1trallw controls. FonMlly Include vinyl chlond9 u pa1 of th• momlorfng p~m ror tha ram•dy l'"onnaly SOICft pubNe lf'Jput on lnl pf0p0$4CI r'l'IO<lne•Uo"' to ll'W flMectf . .n<I Prepara at1 Amenelm.,. to the "'®10 lnduat mocneauo.n1 to tne '9mtcty,

• STATUS OF THE

FIVE-YEAR REVIEW

6

•

•

• FIVE-XEAR REVIEW

• Outshmdmg lssye-s

- ;1e.':~:=-=::=.the~n~~::"~::::r:~~";9~t.;:'"utlled - lncorpcnta the rHUl.s: of the Mld-Pofnf nalu.ttons Into Iha nut FN9--V..~

- lncorporata PU:MIC Input Into Int ntltt Fiv.-YNI' Re'MW

- F""9--YHI' Ravl.w must be completed by S•pt•mber 24. 2D tl or a•rll•

7

(}JU!E§7r!IOM§/ IRIECOMMIEMDA 7r!IOM~

8

APPENDIXC

TABLES

Table 1: Site Chronology

Key Milestones

Site first used for solvents/waste storage facility Initial operations to dispose of the inert waste from approximately 2000 drums Permit issued by SCDHEC for one-time disposal of 300-400 drums with inert waste Site abandoned by the Carolawn Company Site Investigation conducted by the EPA and SCDHEC indicated the presence of contamination (volatile organic compounds and metals) on the Site and in nearby residential wells The EPA initiated cleanup activities at the Site The EPA proposes the Site for inclusion on the National Priorities List (NPL) Site was listed on the NPL Four nearby residents were connected to an alternative water supply Potentially Responsible Parties (PRPs) entered into an Administrative Order on Consent (to remove 17 storage tanks off-site and dispose of waste content at an incinerator) PRPs conducted Remedial Investigation/Feasibility Study(RI/FS) for OU-I pursuant to a Consent Decree Record of Decision (ROD)'for OU- I was signed (selected the remedy for groundwater cleanup based upon I x 10-6 carcinogenic risk factors and proposed MCLs) Remedial Design/Remedial Action(RD/RA) Work Plan was developed and approved Rl/FS was initiated for OU-2 (area located to the north and west beyond the fenced area OU- I ­soils, surface water and sediment in Fishing Creek) Remedial Action for OU- I was formally initiated ROD for OU-2 was signed (No-further Action remedy for the area outside of the fence - soils, surface water and sediment in Fishing Creek) Groundwater Extraction and Treatment System (GWETS) was installed SCDHEC issues a National Pollution Discharge Elimination System Permit (NPDES) Permit for dischar.ge of treated groundwater to Fishing Creek Operation and Maintenance (O&M) of the GWETS was initiated The EPA issued Unilateral Administrative Order (UAO) to PRPs for O&M and monitoring NPDES Permit was modified Preliminary Close-Out Report was developed and signed First Five-Year Review was completed Second Five-Year Review was completed With the EPA and SCDHEC approval. the GWETS was shutdown as part of the planned Enhanced In-Situ Biodegradation (EISB) "Pilot Study" treatment activities. Installation of 14 injection wells and 3 monitoring wells The EPA annroval of the Remediation System Evaluation Report and Action Plan (Action Plan) The first EISB baseline (pre-injection) sampling event was completed The second EISB baseline (pre-injection) sampling event was completed Completion ofEISB treatment consisting of the injection of Newman Zone (a soy-oil based product) Eight post-injection/semi-annual monitorin.g events were conducted Third Five-Year Review was completed The EPA issued a Modified UAO which specified the requirement that a Focused Feasibility Study (FFS) be completed to identify a groundwater remedial action more favorable than the GWETS. Completed the Remedial Design and Construction of the Soil Vapor Extraction System SVE Operation and Maintenance, SVE data collection and groundwater monitoring

Dates

1970 1975 1978 1980

1980

December 1981 December 1982 September 1983

1985

May 1985

1985-1989

September 1989

1991-1992

1992

May 1993

September 1995

1995-1996

1996

October 1996 July 1997

April 1998 May 1998

August 1998 August 2003

July 2004

September 2004 October 2004 October 2004

March 2005 May 2005

July 2005 - April 2008 September 2008

March I 0, 2009

January 2012 Ongoing

Table 2: Groundwater Contaminants of Concern and their Cleanup Goals As Noted in the 1989 Record of Decision

Groundwater Contaminants of Concern

Acetone l, 1-dichloroethane 1,1-dichloroethene

1,2-dichloroethene

I, I, I-trichloroethane Trichloroethene

Lead

Cleanup Goal Basis For the u L Clea nu Goal 700 +

* * 7 MCL

70 - cis Proposed MCL 100-trans Pro osed MCL

200 MCL 5 MCL 5 Pro osed MCL

+ - The value of 700 ug/L for acetone is a lifetime health advisory (LHA) * - No firm cleanup criteria has been established but it is assumed that due to I, 1-dichloroethane similar chemical/physical characteristics with other contaminants present, the levels will decrease proportionally along with the other contaminants.

Table 3: Progress on Recommendations from the 2008 FYR

Section Recommendations

An appropriate decision document should be prepared to add vinyl chloride to the

5.1 list of cleanup goals to be addressed at this Site.

Work with SCDHEC, CSC and the Site property owners to determine the 5.2 appropriate !Cs for the Site.

Continue to evaluate available groundwater treatment technologies to determine whether such technologies would be more effective than the GWETS

5.3 in efficiently restoring the contaminated aquifer. If another alternative is preferred, a decision document (ESD or ROD Amendment) will be issued for the Carolawn Site. EPA should place a notice acknowledging the potential risk, if any, of soil vapor

5.4 migration through future inhabitable structures on the deed of properties within the contaminated area of the plume.

Party Milestone Responsible Date

EPA and SCDHEC

12/31/2009

csc 12/31/2009

csc 12/31/2009

csc 12/31/2009

Action Taken and Outcome

Vinyl Chloride is included in the monitoring program. Vinyl Chloride will be included as part ofa ROD Amendment.

Date of Action

Ongoing

No action Ongoing

CSC conducted the SYE pilot study to collect data to evaluate the potential use of SVE as an Interim Remedial Measure as part of an overall groundwater strategy.

08/23/2010 and

01/06/2012

No action Incomplete

Table 4: Applicable or Relevant and Appropriate Requirements Evaluated in the 1989 ROD

LAW, REGULATION, POLICY AND APPLICATION STANDARD

RESOURCE CONSERVATION AND RECOVERY ACT(RCRA) None

CLEAN WATER ACT(CWAl

40 CFR 122, 125: Discharges of extracted/treated Groundwater will be subject to Substantive National Pollutant Discharge requirements of the NPDES process if discharged to Local stream. NPDES Elimination Systems (NPDES) is administrated by the State.

Discharges of extracted/treated Groundwater will be subject to 40 CFR 403: Pretreatment requirements if discharged to the POTW Effluent Guidelines And Standards: Pretreatment Standards AWQC may be used for discharge Requirements where there are no State

water quality standards Ambient Water Quality Criteria( A WQC)

CAA SECTION 109 AND 40 CFR 50: NAAQS for particulate matter (PM 10) applied to fugitive dust National Ambient Air Quality Standards (NAAQS)

40 CFR 404 (B )( 1 ): Protects the destruction of wetlands by requiring no net lost of wetlands Wetland Protection OCCUPATIONAL SAFETY AND HEAL TH ACT

29 CFR 1910: General standards for work protection Worker safety for construction and operation of remedial action

29 CFR 1090: Regulations for workers involved in hazardous Worker safety for construction and operation of remedial action waste operations

Table 4: Applicable or Relevant and Appropriate Requirements Evaluated in the 1989 ROD (con't)

LAW, REGULATION, POLICY AND STANDARD

INTERGOVERNMENTAL REVIEW OF FEDERAL PROGRAMS

FISH AND WILDLIFE COORDINATION ACT

ENDANGERED SPECIES ACT

SECTION 7(C)

SAFE DRINKING WATER ACT

REQUIREMENTS TO BE CONSIDERED

EXECUTIVE ORDER 12372

40 CFR29

EXECUTIVE ORDERS FOR FLOOD PLAINS <EO 11988)

40 CFR PART 6, SUBPART A

EXECUTIVE ORDERS FOR WETLANDS !EO 11990)

APPLICATION

Protection of fish and wildlife when federal actions result in the control or modification of a natural stream or body of water

Consultation with the fish and wildlife service if action may impact endangered species or Critical habitat

Maximum Contaminant Levels (MCLS) established under the safe drinking water act were found to be relevant and appropriate to remedial action at the Carolawn site. The Cleanup goals for groundwater were established in Section 4 of the ROD for OU- I.

State and local coordination and review of proposed EPA assisted projects

Protection of flood plains affected by remedial action

Protection of wetlands affected by remedial action

Table 5: Changes in Chemical-Specific (MCL) Standards for Contaminants of Concern

Groundwater 1989 ROD Standard Contaminants of Concern

Acetone

I, 1-dichloroethane

I, 1-dichloroethene

1,2-dichloroethene

1,2-dichloroethene

I, I, I-trichloroethane

trichloroethene

Lead

Cleanup Goal (ul?fL)

700+

*

7

70- cis

I 00 - trans

200

5

5

(ug/L)

Previous Standard 700 Current Standard 12,000 Previous Standard * Current Standard 2.4 Previous Standard 7

No Change from Current Standard

Previous Standard Previous Standard 70

No Change from Current Standard

Previous Standard Previous Standard 100

No Change from Current Standard

Previous Standard Previous Standard 200

No Change from Current Standard

Previous Standard Previous Standard 5

No Change from Current Standard

Previous Standard Previous Standard 5 Current Standard 15

+-The value of700 ug/L for acetone is a lifetime health advisory (LHA) * -No firm cleanup criteria has been established but it is assumed that due to 1, 1-dichloroethane similar chemical/physical characteristics with other contaminants present, the levels will decrease proportionally along with the other contaminants.

Table 6: Institutional Controls Summary Table

Area of Interest- Groundwater/Soil Carolawn Property

ICs Needed

Yes

ICs called for in the Decision Documents

Yes

Impacted Parcel

146-00-00-005-000

IC Objective

Restrict groundwater use and

the installation of wells

Area of Interest ­ Groundwater Adjacent Properties

ICs Needed

Evaluation is needed to determine if I Cs are

required

Evaluation is needed to determine if I Cs are

required

ICs called for in the Decision Documents

Yes

Yes

Impacted Parcel

146-00-00-03 7-000

146-00-00-016-000

IC Objective

Restrict groundwater use and

the installation of wells

Restrict groundwater use and

the installation of wells

Instrument in Place

None

Instrument in Place

None

None

_J

Table 7

Site-Wide Vapor Monitoring Results - Individual VOCs

December 2011, September 2012, and March 2013 Vapor Monitoring Data

Carolawn Superfund Site

Fort Lawn, South Carolina

VM-1 I VM-2 VM-4 I VM-5 I VM-6 I VM-7 VM-S VM-9 I VM-10

Oat• Sampled lZ/16/2011 I 4/l.5/20ll I 11/H/1011 I 9/l0/2012 4/25/2Dll 11/16/2011 I 4/25/2013 I 11/15/2011 J 9/10/2012 I 4/25/l.OU I 11/lS/1011 'J/10/2012 I 4{25/ZOIJ I 12/l!t/1011 4/25/20ll 11/lS/1011 9/10/2012 4/2S/2Dl3 I 11/H/2011 I 4/25/l.OU I 11/16/1011 4/25/lOll

M•thod T0-1'; I T0-15 I T0-15 I T0-15 T0.15 I TO.IS I ro.1s I T0-15 I T0-15 I TO·H• JO.JS I T0-15 I 10.1s I T0-15 I I

o.ooss 0.024 0.063 0.033 0.1 0.039

1, 1-0ichloroeth"ne 75-JS-4 0.24 0.46 0.14 0.18 012 a.on 0042 0.015 0.046 0.033 0.026 7.6 0073 6.4 0.058 0.46 Q.51 0.42 0.26

1,1-Dichloroeth;me 75-J.i-J 0.064 0 .. 38 0.0084 0.2 0.15 0.033 0.016 0.023 0.034 0.17 0.034 0.04 0.2 0.061 0.13 Cls- J,;i-Dlchloroethene 0.94 2.1 0.068 0.36 041 0 .. 14 0026 0.]3 0.12 0.091 0.2 0026 0.055 0.13 0.47 0.057 0.068 0.12 0.028 0.12

Chlorciform 67-6t>-3 0 .. 29 0.14 0.039 0.39 038 0.021 0.016 O.ot8 0.015 0.031 0 .. 34 0 ..064 0 .. 17 1.5 0.1

Tric:hlor~thene 79-01-6 6.4 4.9 J.4 1.2 1.3 09 0.18 3.3 0.5 0.9 0.88 1.2 0.2 6.5 0.85 11 0.23 0.081 0.63 1.8 '·' 2.1 Tetrachloroethene 127-18-4 0.022 0.11 0.064 1.1 098 0.0087 0.023 0 ..01 0.015 0.019 0 ..055 0.04 0.32 0.02 0.048 0.1 0.065 0.56 0 ..092 5.4

1,1,1-1richloroeth1ne 11-55f> 0.044 O.D15 0.05 0.11 0.18 0.24 0.024 0.033

1, t,2-'frkhloro"thine 79-00-<

Carbon Tetrachloride 0.018

Meth-;lene Chloride 0.011 O.OB O.o16 006 0.71 0 ..18 1,2-Dichloroethane 107-06-:! 0.032 0.037 0.077 0.052 Vinylc:hlorlde 75-01-4

Tr11ns-1,2-Dkhloroethene 15t.-t.CJ-5

Total llOC~ (ppmv) 8.0 8.1 1.72 3.48 3.. 45 1.13 0.29 4.37 0 .. 76 1.10 1.06 1..0 0 ..27 14.. 67 1..07 20.. 68 0.73 0.18 1.58 5.. 47 4.00 10.28

S1n'1plelD VM-11 VM-12 I VM-13 VM-14 I VM·lS VM-16 VM-17 I VM-18 VM-19

D1t1S.mpled 12/16/2011 '/10/7011 4/1.'f>/20B 12/15/2011 I 4/7S/7011 I 12/15/J:Oll I 9/10/1011 I &/1'f>/70U 12/15/2011 'J/10/1011 4/2'f>/20U I 12/1'/2011 I 9/10/7012 &/25/201J 12/15/1011 4/7S/101l 12/15/20lll 4/lS/'10ll l11/16/2011 '/10/2012 &/2S/70U 1/13/2012 'J/10/1.011

,... T0-15 I T0-15 I TO-IS I T0-15 I T0-15 l T0-15 I TO·IS I 1 T0-15 TO-IS I I T0-15

Freon-11 75-69-4

l,l·Di£h1oroethene 75-35-4 0.054 0 .. 11 0.039 0.042 0.64 0.023 0 ..025 4.5 0.052 0074 3.4 0.019 l,l-Di£hloroeth;ine 75-:U-3 0.2 0.35 0.035 1.2 0021 0057 1.5 0.11 0..021 0.035 0.0089 0 ..015

Ci~l,1-Dkhloroethene 156-59-2 0.033 0 ..094 1.1 0 ..09 0.015 0.65 0.22 15 0.061 130 15 0.53 0 ..029 4.1 2.8 0.048 48 0 ..82

Chloroform 67-6t>-3 0.16 0.053 0.62 0.36 0 ..02 1.2 0 ..024 0.022

Trich1ctroethene 79-01-6 0.24 0.021 0.89 2.4 014 0.2 0.25 0.053 23 0.022 0.4 210 3.1 44 11 7.7 210 5.6 J.8 Tetrachloroethene 127-18-4 0.037 4.3 0.047 0.026 0.019 0.42 0.14 003 0 ..021 0.032 0 ..021

1, 1, t-'frlchloroeth;ine 71-S:'i-6 0.56 0.032 0 ..071 0.02

1, 1,2-frlchloroeth1ne 79-00-~

Carbon Tetrachloride 56-2..1·5

Methylene Chloride 75-042

1,2-01£hloroethane l07-1Y:>-2 0.012

Vinyl chloride 75.Ql-4 0.02 0.062 0.02 0 ..033

Tr;ins-1,2-Dlchloroethene 156--60-5 0.036 0.018 0.013

Total llOCs (ppmv) 0.27 0.06 5.. 70 4 .. 06 0.29 0 .. 23 3.. 14 0 ..47 38.. 14 0 ..02 0.46 342.. 76 3 .. 20 4 .. 17 49 ..03 0 .. 39 15.26 0.00 10.. 62 FLOODED 0.07 262 .. 60 7.71 2.66

1.Alld1U;ireinopmv

'1.0'11yconstit•.."''1!5dt"tected;irepresented.

3.. Total VOU = svm of ;ill detected pi ram.ten;

·Table 8

Site-Wide Vapor Monitoring Results - Total VOCs

December 2011, September 2012, and March 2013 Sampling Events

Carolawn Superfund Site

Fort Lawn, South Carolina

Vapor

Well 12/16/2011

Total VOCs

9/10/2012 4/25/2013 Percent Change

VM-1 8.00 NS 8.10 1.3%

VM-2 1.72 3.48 3.45 101%

VM-4 1.13 NS 0.29 -74.3%

VM-5 4.37 0.76 1.10 -74.8%

VM-6 1.06 1.43 0.27 -74.5%

VM-7 14.67 NS 1.07 -92.7%

VM-8 20.68 0.73 0.18 -99.1%

VM-9 1.58 NS 5.47 246%

VM-10 4.00 NS 10.28 157%

VM-11 0.27 0.06 5.70 2011%

VM-12 4.06 NS 0.29 -92.9%

VM-13 0.23 3.14 0.47 104%

VM-14 38.14 0.02 0.46 -98.8%

VM-15 342.76 3.20 4.17 -98.8%

VM-16 49.03 NS 0.39 -99.2%

VM-17 15.26 NS 0.00 -100%

VM-18 10.62 NS 0.07 -99.3%

VM-19 262.60 7.71 2.66 -99.0%

Average 43.3 2.3 2.5 -94.3%

Notes:

1. All data are in ppmv

2. Total VOCs =sum of all detected parameters

3. The percent change estimated is based on the December 2011 and April 2013 data.

4. The December 2011 sampling event occurred approximately 2 weeks prior to startup of the SVE

system. The September 2012 and April 2013 sampling events occurred approximately 35 and 66

weeks after startup of the SVE system, respectively; the September 2012 and April 2013 sampling

events were preceded by SVE system shutdown periods of approximately 4 and 6 weeks,

respectively.

5. Vapor wells that are connected to the SVE extraction network are the following: VM-2, VM-5,

VM-6, VM-8, VM-11, VM-13, VM-14, VM-15, VM-18 and VM-19. As noted in the report, VM-10

was connected to the vacuum system via a short length of flexible hose.

Table 9 - Deed Documents for the Carolawn property

Date Type of Description Book# Page# Document

1976 Deed Max G. Gergel acquired the Site property from Columbia Organic 481 113 Chemicals, Inc.

1977 Deed Carolawn Company, Inc. which acquired the Site property from 489 363 individuals, Max G. Gergel, James Q. McClure and Henry M. Tishcher. The whereabouts of the Carolawn Company officers are unknown. ___,,.,,.,~2001 Condemnation The South Carolina Department of Transportation acquired by 793

Notice Eminent Domain Procedures 1.320 acres of the 81-acre property for a road.

APPENDIX D

FIGURES

•

•

~

l ~

1i ~ ! :i .! n ~

SITE LOCATION MAP = "' ~ Carolawn Superfund Site 5093 Morrison Road ~ Fort Lawn , South Carolina ii

- - ­600~

Fee Geosyntec t> FigureAdapted From: Digital Raster Graphic (DRG) for the consultants Fort Lawn 7.5 Minute Quadrangle, South Carolina 1

Kennesaw, Georg ia JULY 2013 De artment of Natural Resources •

• • •

Extraction Well

0 Injection Well Carolawn Superfund Site 0 Monitoring Well Fort Lawn, South Carolina

HMt Geosyntec t>Former extraction wells EW-03R and EW-05 were converted to Figuref injection wells. Former extraction wells EW-02 and EW-03 were consultants ~ converted to monitoring wells . 2

Kennesaw, Georgia JULY2013

"9 ~

~ ~ ~ ~

;r~-------.-a;.:11 E WELL LOCATIONS ! Active Extraction VVell

Carolawn Superfund Site Groundwater Extrad.ion \Nell Fort Lawn, South Carolina ~ Groundwater Injection Well

:t Groundwater Monitoring \Nell

R

Geosyntec t> Figure Vadoze Zone \Nell

37.5 75 150 Feet consultants! -- Property Boundary

Fence Line !:!_. Kennesaw Geor ia JULY 2013 i L-----'va"'c""u"'um.::..:..:;H•::::ad::o•::..rP'-'1=------­'· $ • ~ • •

3

i

• • •

Property Line

Fence Line

Wells ! 0 Monitoring Well (Groundwater Elevation in ft . MSL)

0 Injection Well (Groundwater Elevation in ~ MSL)

-$- Extraction Well (Groundwater Elevation in ft . MSL)

Groundwater Potentiometric Surface Contour {Elevation in ft. MSL) Dashed \Miere Inferred

Interpreted Groundwater Flow Direction

Well Not Used For Contouring

GROUNDWATER POTENTIOMETRIC SURFACE AND FLOW MAP

25 March 2013 Carolawn Superfund Site Fort Lawn, South Carolina

Geosyntec Figure consultants

Kennesaw, Georgia JULY 2013

4

• • •

Carolawn Property and Surrounding Properties

_____I Surrounding Properties Carolawn Property

146-00-00-XXX-XXX Parcel Number -----Road I I I Railroad

Carolawn Superfund Site, Fort Lawn, SC Figure September 2013 5

• • •

SITE WIDE VAPOR SAMPLING RESULTS FROM APRIL 2013

Well ID Total voes in Soil Vapor Carolawn Superfund Site

expressed as the summation Fort Lawn, South Carolina -$- Vadose Zone Well of detected voes (ppmv)

0 37 .5 75 Groundwater Extraction Well Geosyntec e> FigureDecreasing Concentration

-$- Groundwater Monitoring Well D Increasing Concentration consultants-- Property Boundary

- -- Fence Line D No Change in Concentration Kennesaw, Georgia JULY 2013

6

--100 160-

i......-- ............

.-~ ~ -

' . /

>

10 120 ~ >; ,,­~ ,,cu Cl)

U; 0 .c E-Cl)... ~ cu II)

II)0::: 80 cu

Iii > System Off ::!: 0 0KnockoutE

\ l 0

Cl) Tank Full >0::: Cl)

II) >;0 .!!0 > ~ :::I

~. !\ ~ E0.1 40 :::I

,~ ~ 0 ~\ l! .... ~ v \ / .... ~~ .... , v ,, ........ '

System System Shutdown Shutdown I I I I I I0.01

~

. t 0 -+-Mass Removal Rate Cummulative Mass Removal

i SVE SYSTEM voe RECOVERY

Carolawn Superfund Site

Fort Lawn, South Carolina

Geosyntec t> Figure consultants

~ 1--~~~~~~ ~~-----<

z..__~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~__,__K_en_n_es_a_w_G_e_o~rg_ia_..~_Ju_ly~2-0_13~~~~~,

• • • 7

• • •

...... lf15'2oot -...... 111SIH10 lrWHll

W1t'21U 1121/MU llttnoU llnntU

'"'""'

ll!Hl I'& Cil·J 1:::1Ha;:

~..... -...... .... ........... .. .HO ... •Mnttt ND HO HO HO HO

tt2112f11 HD HO HO llJllMU ND ND HO llttl20U ND HO HO

ND ND HO

"""'"

"""'"

JGC ga.! UK;f HI HO,,. ..,,,. .., rA HO LI HO 16 NO ILi HO j,l NO 1$.7 NO1,1-DCE =1,1-Dichloroethene (MCL =7)

Cis-1,2-DCE = Cis-1 ,2-Dichloroethene (MCL =70) TCE =Trichloroethene (MCL = 5)~ Wells ND = Non-Detect

~ Fence Line

CONCENTRATION OF DETECTED TCE, Cis-1 ,2-DCEi 0 Monttonng Well AND 1,1-DCE IN GROUNDWATER (2009 - 2013)

Carolawn Superfund Sitel Nl!l§ Fort Lawn, South Carotma ' Concentrations are In ugll..l Concentral.Jons below th e MCL are~- Geosyntec t> Figure

consultants! 8 Kennesaw, Georgia AUGUST2013

APPENDIX E

SITE INSPECTION CHECK FORM, INTERVIEW DOCUMENTATION FORM AND PHOTOGRAPHS

--

--

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Appemnix lE: Site inspection CheckHst

FIVE-YEAR REVIEW SliTE INSPECTION CHECKLIST

D. SITE INFORMATION

Site name: Carolawn Superfund Site Date of inspection: 03/07/2013

Location and Region: Fort Lawn, Chester County, SC EPA ID: SCD980558316

Agency, office, or company leading the five-year review: EPA/SCDHEC

Weather/temperature: Sunny

Remedy Includes: (Check all that apply) D Landfill cover/containment D Monitored natural attenuation [8J Access controls D Groundwater containment .. [8J Institutional controls D Vertical barrier walls [8J Groundwater pump and treatment D Surface water collection and treatment [8J Other GWETS Shutdown in July 2004. Soil Vapor Extraction Pilot Study is being used as an interim measure to achieve faster performance of the remedial action objectives.

Attachments: D Inspection team roster attached D Site map attached

II. INTERVIEWS (Please refer to the Site Interview Documentation Form)

I. O&M site manager Geosxntec Name

Interviewed [8J at site D at office D by phone

Problems, suggestions; D Report attached

2. O&M staff Name

Interviewed D at site D at office D by phone

Problems, suggestions; D Report attached

Senior Engineer Title

Phone no. 678.202.9507

03/07/2013 Date

- ­Title

I I Date

Phone no. - ­

E-1

3.

4.

l.

2.

3.

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 __ Contact I I

Name Title Date Phone No. Problems; suggestions; 0 Report attached __

Agency __ Contact I I

N~e T~ Date Phone No. Problems; suggestions; 0 Report attached __

Agency __ Contact I I

Name Title Date Phone No. Problems; suggestions; 0 Report attached __

Agency __

Contact mm/dd/yyvv Date

Name Title Phone No.

Problems; suggestions; 0 Report attached __

Agency __

Contact mm/dd/yyvv Date

Name Title Phone No.

Problems; suggestions; 0 Report attached __

Other interviews (optional) 0 Report attached

Ill. ON-SITE DOCUMENTS & RECORDS VERIFIED (Check all that apply) ..O&M Documents

0 O&M manual l8J Readily available l8J Up to date ON/A

0 As-built drawings 0 Readily available 0 Up to date [8J N/A

0 Maintenance logs l8J Readily available l8J Up to date ON/A

Remarks: GWETS Shutdown in July 2004. Soil Vapor Extraction Pilot Study is being used as an interim measure to achieve faster performance of the remedial action objectives.

Site-Specific Health and Safety Plan l8J Readily available l8J Up to date ON/A

!8J Contingency plan/emergency response plan l8J Readily available !8J Up to date ON/A

Remarks:

O&M and OSHA Training Records [8J Readily available [8J Up to date ON/A

Remarks:

E-2

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--

--

--

4. Permits and Service Agreements

0 Air discharge pem1it .. 0 Readily available 0 Up to date ON/A

12] Effluent discharge 12] Readily available 12] Up to date ON/A

0 Waste disposal, POTW 0 Readily available 0 Up to date ON/A

0 Readily available 0 Up to date ON/A0 Other permits

Remarks: GWETS Shutdown in July 2004. Soil Va12or Extraction Pilot Study is being used as an interim measure to achieve faster 12erformance of the remedial action objectives. As a result only 12urge water from monitoring activities is 12rocess through the system. Effluent discharge averages less than once 12er year.

5. Gas Generation Records 0 Readily available 0 Up to date 12] N/A

Remarks:

6. Settlement Monument Records 0 Readily available 0 Up to date 12] N/A

Remarks:

7. Groundwater Monitoring Records 12] Readily available 0 Up to date ON/A

Remarks:

8. Leachate Extraction Records 0 Readily available 0 Up to date 12] NIA

Remarks:

9. Discharge Compliance Records

0Air D Readily available 0 Up to date ON/A

12] Water (effluent) 12] Readily available 12] Up to date ON/A

Remarks: GWETS Shutdown in July 2004. Soil Ya12or Extraction Pilot Study is being used as an interim measure to achieve faster 12erformance of the remedial action objectives. As a result only 12urge water from monitoring activities is 12rocessed through the system. Effluent discharge averages less than once 12er year.

10. Daily Access/Security Logs 12] Readily available 12] Up to date ON/A

Remarks: ..

IV. O&M COSTS

I. O&M Organization

0 State in-house 0 Contractor for State

0 PRP in-house 12] Contractor for PRP

0 Federal Facility in-house 0 Contractor for Federal Facility

.. 0 Other

E-3

2. O&M Cost Records

D Readily available D Up to date

D Funding mechanism/agreement in place D Unavailable .

Original O&M cost estimate Aggroximatelv $636K (10 Years)/ $898K (30 Years) D Total annual cost by year for review period if available

From 01/12/2012 To 08/14/2013 $200,000 1:8] Only conducted O&M for the OU-1 SVE - Pilot Study Remedy for 18 months. Please Date Date ­$250,000 refer Section 4.3 for general summary of al 1

costs since the last Five-Year Review. Total cost

3. Unanticipated or Unusually High O&M Costs During Review .. Period

Describe costs and reasons: The GWETS ogerated during the geriod of July 28, 1997 through July 19, 2004. With EPA and SCDHEC aggroval, the GWETS was shutdown on July 19, 2004 as gart of the glanned EISB activities. Therefore, these activities were gerformed for a seven year geriod. During ogeration of the GWETS, there were no unexgected O&M difficulties or costs, excluding a small amount of costs for reviewing the NPDES germit. The EISB Pilot Studv costs were glanned for, but are not routine. Since 1989 ROD issuance, the CSC sgent aggroximately $6,000,000 to imglement the remedy selected in the 1989 ROD for OU- I. Prior to the GWETS shutdown, O&M costs were $200,000 to $250,000 ger year. Since the GWETS shutdown, the CSC has sgent aggroximatel:i:: $1,000,000 to imglement EISB activities and continue the comgrehensive monitoring grogram reguired by the Action Plan. The EISB Pilot Study was discontinued following the Agril 20 I 0 injection well rehabilitation and dual ghase extraction tests. Remedial strategies relating to the SVE gilot study activities, including SVE system construction, monitoring and O&M costs as well as the continued comgrehensive groundwater monitoring grogram, have averaged aggroximately $225,000 ger year.

V. ACCESS AND INSTITUTIONAL CONTROLS 1:8:1 Applicable ON/A

A. Fencing

I. Fencing damaged D Location shown on site map 1:8:1 Gates secured ON/A

Remarks: -­ ..

B. Other Access Restrictions

I. Signs and other security measures D Location shown on site map ON/A

Remarks: Sign gosted on front gate - No Tresgassing

E-4

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--

--

--

--

c. Institutional Controls (ICs)

I. Implementation and enforcement

Site conditions imply ICs not properly implemented 0Yes 0No ~NIA

Site conditions imply I Cs not being fully enforced 0Yes 0No ~NIA

Type of monitoring (e.g., self-r.eporting, drive by) I Cs have not been implemented at the Site.

Frequency __

Responsible party/agency

Contact I I

Name Title Date Phone no.

Reporting is up-to-date 0Yes 0No ~NIA .'

Reports are verified by the lead agency 0Yes 0No ~NIA

Specific requirements in deed or decision documents have been met Oves 0No ~NIA

Violations have been reported 0Yes 0No ~NIA

Other problems or suggestions: 0 Report attached

2. Adequacy D ICs are adequate D ICs are inad~quate ~NIA

Remarks: I Cs have not been implemented since no viable landowner exists.

D. General

I. Vandalism/trespassing 0 Location shown on site map ~No vandalism evident

Remarks: There was no evidence of vandalism.

2. Land use changes on site ~NIA

Remarks: .'

3. Land use changes off site ~NIA

Remarks:

VI. GENERAL SITE CONDITIONS

A. Roads ~ Applicable ON/A

I. Roads damaged ~ Location shown on site map ~ Roads adequate ON/A

Remarks: .'

B. Other Site Conditions

Remarks: - ­

VII. LANDFILL COVERS 0 Applicable ~NIA

VIII. VERTICAL BARRIER WALLS 0 Applicable ~NIA

IX. GROUNDWATER/SURFACE WATER REMEDIES 0 Applicable ~NIA

A. Groundwater Extraction Wells, Pumps, and Pipelines ~ Applicable ON/A

E-5

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I. Pumps, Wellhead Plumbing, and Electrical

[8J Good condition 0 All required wells properly operating 0 Needs Maintenance ON/A

Remarks: Due to EISB Activities and currently SVE Pilot Study, GWETS is no longer OQerating. However, the system comQonents are stored in such a way that the GWETS can be re-started and OQerational within 14 days.

2. Extraction System Pipelines, Valves, Valve Boxes, and Other Appurtenances .·

[8J Good condition 0 Needs Maintenance

Remarks:

3. Spare Parts and Equipment

[8J Readily available 0 Good condition 0 Requires upgrade 0 Needs to be provided

Remarks:

B. Surface Water Collection Structures, Pumps, and Pipelines O'Applicable [8J NIA

I. Collection Structures, Pumps, and Electrical

0 Good condition 0 Needs Maintenance

Remarks:

2. Surface Water Collection System Pipelines, Valves, Valve Boxes, and Other Appurtenances

0 Good condition 0 Needs Maintenance .·

Remarks:

3. Spare Parts and Equipment

0 Readily available 0 Good condition 0 Requires upgrade 0 Needs to be provided

Remarks:

c. Treatment System [8J Applicable ON/A

E-6

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I. Treatment Train (Check components that apply)

0 Metals removal 0 Oil/water separation 0 Bioremediation

1:8] Air stripping .. 1:8] Carbon adsorbers

0 Filters

0 Additive (e.g., chelation agent, tlocculent)

0 Others

1:8] Good condition 0 Needs Maintenance

1:8] Sampling ports properly marked and functional

1:8] Sampling/maintenance log displayed and up to date

1:8] Equipment properly identified

1:8] Quantity of ground water treated annually. The GWETS is currentl:r: not ogerating. During ogeration of the GWETS aggroximatel:r: 2.3 million gallons of water were treated ger :rear.

0 Quantity of surface water treated annually

Remarks: The GWETS is ogerated geriodicall:r: b:r: a certified wastewater ogerator, to treat gurge water from samgling events ad storm water that geriodicall:r: collects in the s:r:stem. The GWETS effluent is treated b:r: liguid-ghase granular activated carbon {GAC} and the effluent is samgled to confirm comgliance with NPDES germ it reguirements ger the discharge germit reguirements. The effluent samgles have been non-detect for man:r: :rears. The Site is insgected about once ger month.

2. Electrical Enclosures and Panels (properly rated and functional)

ON/A 1:8] Good condition 0 Needs Maintenance Remarks:

3. Tanks, Vaults, Storage Vesse_!s

ON/A 1:8] Good condition 0 Proper secondary containment 0 Needs Maintenance

Remarks:

4. Discharge Structure and Appurtenances

ON/A 1:8] Good condition 0 Needs Maintenance Remarks:

5. Treatment Building(s)

ON/A 1:8] Good condition (esp. roof and doorways) 0 Needs repair

1:8] Chemicals and equipment properly stored

Remarks:

6. Monitoring Wells (pump and treatment remedy)

1:8] Properly secured/locked 1:8] Functioning 1:8] Routinely sampled 1:8] Good condition

[8]Wells can be easily located ~ Site 0 Needs Maintenance ON/A Plan w/ photographs is available in the Treatment Building.

Remarks: Soil Vagor wells (used during the SVE Pilot Stud:r:) and Injection wells (used during the EISB Pilot Stud:r:) are in good condition.

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I D. Monitoring Data

l. Monitoring Data

1:8] Is routinely submitted on time D Is of acceptable quality

2. Monitoring data suggests:

1:8] Groundwater plume is effectively contained in 1:8] Contaminant concentrations are declining (some most areas. what)

E. Monitored Natural Attenuation I. Monitoring Wells (natural attenuation remedy)

D Properly secured/locked D Functioning D Routinely sampled D Good condition

..D All required wells located D Needs Maintenance 1:8] N/A

Remarks: - ­X. OTHER REMEDIES

If there are remedies applied at the site and 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. (NA)

XI. OVERALL OBSERVATIONS A. Implementation of the Remedv Although ogerating as designed, the data collected between 1996 and 2003 indicated the GWETS would not be effective in reducing voe groundwater concentrations to accegtable levels within ten years as described in the 1989 ROD due to site-sgecific hydraulic challenges. As a result, the EPA recommended a system ogtimization study to consider the use of alternative remedial technologies to address voes in groundwater. In resgonse, the esc imglemented Enhanced In Situ Biodegradation (EJSB} treatment of groundwater as a 'gilot study' to accelerate the reduction of VOC concentrations in groundwater. The CSC shutdown the GWETS on July 19, 2004.

The ese comgleted EISB injection of a substrate consisting of a soy-oil based groduct known as Newman Zone in May 2005. 4 years after the GWETS shutdown and EISB imglementation, the VOC distribution and glume extent in Site groundwater did not significantly change and the greatest VOC concentration areas remained stable. Based on the remedial grogress observed between 2003 and 2008, the third FYR recommended further evaluation of technologies other than the GWETS and EISB to identijy a technology that would more effectively and efficiently restore the contaminated aquifer for future use.

The CSC submitted a draft FFS to EPA in January 2010 and subsequently met with EPA to discuss the same. Jn August 2010, the CSC conducted a limited soil vagor extraction (SVE} study to collect data to evaluate the gotential use of SVE as an Interim Remedial Measure (!RM} as gart of an overall groundwater remediation strategy. The results of the SVE study indicated SVE as a feasible aggroach to reduce VOC mass in the subsurface (vadose zone} which could result in reduced voe concentrations in groundwater. Following discussions with the South Carolina Degartment of Environmental Health and Control (SCDHEC), the CSC and the Communi!}:: Advisory Groug (eAG}, the EPA issued the Notice to Proceed with the remedial design and construction of the SVE system. Construction of the SVE system was comgleted in January 2012. Ogeration of the SVE system has reduced VOC mass from the subsurface and is exgected to reduce the flux of VOCs to groundwater which will allow groundwater concentrations to decline over time. Aggroximately 155 lbs of VOCs have been removed during seventeen months ofSVE system ogeration. In com12arison, the GWETS extracted 35 lbs of VOCs from the groundwater Qlume during 7 years of 012eration. SYE system 012erational data and groundwater 12lume monitoring suggest VOC conditions are imgroving, source area mass is reducing, and the VOC groundwater glume is generally stable and decreasing.Voe mass removal from the SVE system will continue to be monitored to assess the imgact of the SYE System on groundwater conditions. This gerformance data will be used to SUQQOrt comgletion of the FFS which could lead to modijying the 1989 ROD.

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B. Adequacy ofO&M In com2arison to the GWETS, there is minimum O&M 2resence due to the 2revious EISB Pilot Study and the \ current SVE Pilot Study. There are monthly visits. Current O&M activities are adeguate. If another alternative is 2referred, a decision document (ROD Amendment) will be issued for the earolawn Site. The O&M and monitoring 2rogram will be modified as a22ro2riate.

c. Early Indicators of Potential Remedy Problems The remedy was functioning as intended by the 1989 ROD. The 1989 ROD estimated I 0 years to achieve MC Ls. However, it was subseguently estimated that the GWETS would have 02erate for at least an additional 62 years to achieve MCLs due Qrimarily to the low yield of the bedrock formation. In res2onse to this issue, the GWETS was shutdown and two 'Qi lot' studies were conducted in an effort to accelerate the reduction of voes in ground water. Absence of2um2ing has not resulted in sustained increasing voe concentration trends near the former waste storage areas, indicating that the greatest voe Qlume region is stable. 02eration of the SVE system has reduced voe mass from the subsurface and is ex2ected to reduce the flux of voes to groundwater which will allow groundwater concentrations to decline over time. A22roximately 155 lbs ofVOes have been removed during seventeen months of SVE system 02eration. In com2arison, the GWETS extracted 35 lbs ofVOes from the groundwater 2lume during 7 years of 02eration. SVE system 02erational data and groundwater 2Iume monitoring suggest voe conditions are im2roving, source area mass is reducing, and the voe groundwater Qlume is generally stable and decreasing.Voe mass removal from the SVE system will continue to be monitored to assess the im2act of the SVE System on groundwater conditions. This 2erformance data will be used to SUQQOrt com2Ietion of the FFS which could lead to modifring the 1989 ROD. The O&M and monitoring 2rogram will be modified as a22ro2riate.

D. Onnortunities for Optimization The 2erformance data from the SVE Pilot Study and the ongoing groundwater monitoring will be used to SUQQOrt com2Ietion of the FFS which could lead to modifring the 1989 ROD.

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Appendix E: linuteJrView Docu.nmentatfton Form Interview Form for the Third Carolawn Site Five-Year Review

Site Name: Carolawn JEJPA ID No.: SCD9805558316

!nterviewer Name: Yvonne 0. Jones

Affiliation: US EPA

Subject's Name: Todd Hagemeyer ________ Affiliation: Geosyntec Consultants _________

Subject's Contact Information: 678-202-9500 thagemeyer@geosyntec.com

Time:__l~2..,.p~m___Date: 9/11/13 Type of Interview:

1. What is your impression of the project? (general sentiment)

Overall, the soil vapor extraction (SVE) system operational data and groundwater monitoring data suggest that voe mass.in the subsurface is being reduced, and concentrations of voe in groundwater are generally stable or decreasing. Completion of the design, installation, and operation of an SVE system as an Interim Remedial Measure (IRM) over the last year and a half has been a positive step toward identifying a remedy more effective than the previously operated groundwater pump and treat system which was shutdown in 2004. The SVE system operation is proving to be an effective means of VOC source mass removal at the Site. Approximately 155 pounds (lbs) of VOCs have been removed during the first 71 weeks of SVE system operation (January 2012 through June 2013); for comparison, the groundwater extraction and treatment system (GWETS) removed approximately 35 lbs ofVOCs during its 7.5 years of operation. As is typical, the mass removal rate Of the SVE system has decreased with time due to the ongoing reduction of VOC mass in the vadose zone. At present, the voe mass removal rate is relatively steady at approximately 1 pound (lb) of VOCs/month. System effectiveness is evaluated quarterly and optimization efforts implemented as needed. The benefit to site-wide remediation will continue to be evaluated and recommendations regarding operation provided as appropriate.

Though vadose zone source removal of VOCs is not expected to have a direct or immediate impact on groundwater quality at existing individual groundwater monitoring wells, it is anticipated that VOC source removal will indirectly result in improvements to groundwater quality over time as source depletion reduces VOC mass flux into the groundwater. The observed ·trends over the last five years of groundwater monitoring indicate that natural attenuation processes also serve an important function at the Site.

In summary, significant progress towards site remediation appears to have been made during the past five years. Based on the ongoing success of the SVE system, we anticipate that the positive direction to continue.

2. [s the remedy functioning as expected? IH!ow well is the remedy performing?

As stated in the most recent SVE System Status Report (July 2013), approximately 155 lbs ofVOCs have been removed during the first 71 weeks of SVE system operation (January 2012 through June 2013). Currently, VOC mass removal rates are I eve! ing off at a still significant rate of approximately J pound (lb) of VOCs/month..For comparison, the GWETS remedy removed a total of 35 lbs of VOCs from the groundwater plume during 7 years of operation. In conjunction with the observation that voe concentrations in groundwater are generally stable or decreasing, the SVE system appears to be an effective Interim Remedial Measure (IRM) that is likely to facilitate completion of a Focused Feasibility Study (FFS) (note: Draft FFS completed in January 20J 0) which could lead to modifying the 1989 ROD.

3. What does the monitoring data show? Are there any trends that show contaminant levels are decreasing?

Groundwater VOC data collected through March 2013 indicate that the overall extent of the voe plume remains relatively stable while voe concentrations at many wells are showing decreasing trends. For example, trichloroethene (TCE) concentrations in MW-6 (representing the highest TCE concentrations detected at the site) have shown a, steady dee I ine and a 30% reduction in dissolved-phase TCE from the period of March 20J J through March 20J3. Additionally, TCE concentrations in downgradient wells located in the vicinity of Fishing Creek (MW-JOA, MW-JOB, MW-1 lA and MW-1 IB) show general stable conditions with decreasing trends with some seasonal fluctuations during the last five years of groundwater monitoring.

4l. is theR"e a continuous on-site O&M presence? U so, please describe staff and activities. U, there is. not a continuous on-site pR"esence, descR"ibe staff and frequency of site inspections and activities. The SVE system is inspected on a monthly basis by Geosyntec staff. Inspection activities include monitoring of airflow and conducting periodic sampling of SVE system effluent. Also, the GWETS is inspected on a monthly basis by Geosyntec staff. The GWETS is operated periodically by a certified wastewater operator (Geosyntec), to treat purge water from sampling events and storm water that periodically collects in the system. The GWETS effluent is treated by liquid­phase GAC and the effluent is sampled to confirm compliance with NPDES permit requirements.

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5. Have there been any significant changes in the O&M requirements, maintenance schedules, or sampling routines since start-up or in the last five years? If so, do they affect the protectiveness or effectiveness of the remedy? Please describe changes and impacts.

No.

6. Have there been unexpected O&M difficulties or costs at the site since start ­up or in the last five years? If so, please give details.

No.

7. Have there been opportunities to optimize O&M, or sampling efforts? Please describe changes and resultant or desired cost savings or improved efficiency.

Periodic system optimization of the SVE system has proved to be beneficial in maximizing voe removal. Soil vapor sampling performed after a period of system shutdown/equilibration has provided information to direct extraction to the areas of highest voe concentrations.

As described in a letter to EPA dated September I 0,-·2013, Geosyntec has proposed to perform a groundwater sampling study to compare passive bag diffusion sampler and low-flow sampling techniques with traditional methods in an effort to continue to provide high quality data while reducing field efforts required in data collection and reducing the volume of investigation derived wastes (IDW) generated.

8. Do you have any comments, suggestions, or recommendations regarding the project?

In general, significant remedial progress has been achieved at the Site during the past five years, particularly with respect to the SVE system's removal of VOe source mass from the vadose zone (i.e., its primary objective as an IRM). Mass removal from the vadose zone will reduce the voe flux to the groundwater and potentially enhance the plume attenuation mechanisms contributing to the observed decreasing groundwater concentration trends. We recommend that the potential effect of the SVE system on groundwater concentrations continue to be monitored, the FFS be completed, and a modification to the 1989 ROD be considered. A transition to a monitored attenuation remedy should be evaluated based on the removal of voe source mass and current groundwater trends observed at the Site.

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Appendix E: Site Photographs

Carolawn Superfund Site Fourth Five-Year Review •

Photograph 1: Treatment System Building and Fenced Area •

Photograph 2: Ground Water Extraction Well -Outside View •1

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Photograph 3: Treatment System Control Panel

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• Photograph 4: Treatment System Building Restroom,

Eye Wash Area & Control Panel

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Photograph 5: Treatment System Components

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Photograph 6: Treatment System Components •3

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Photograph 7: Treatment System Components Modified to Conduct the SVE Pilot Study

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• Photograph 8: Treatment System Components Modified to Conduct the SVE Pilot Study

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Photograph 9: Soil Vapor Monitoring Well-Inside View

Photograph 10: Circle S Farms (Borders The Site To The West)

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Photograph 11: Providence Fish & Game (Borders The Site To The East)

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