COMMUNITY INVOLVEMENT PLAN

Ram Leather Care Site Charlotte, Mecklenburg County, North Carolina

September 2018

\ 55 Ui \W CD

U. S. ENVIRONMENTAL PROTECTION AGENCY REGION IV

Approved by> Date: 7 /

111£ 182 The S. Environmental Protection Agency's (EPA)

Superrind Community Involvement Program is committed

TO PROMOTING COMMUNICATION BETWEEN CITIZENS AND THE AGENCY.

Active public involvement is crucial to the success of any public project.

EP.A'S COMMUNITY INVOLVEMENT ACTIVITIES AT THE

Ram Leather Care Site

ARE DESIGNED TO

Inform the public of the nature of the environmental issues associated with the site.

Involve the public in the decision-making process that will affect them.

Involve the public in the responses under consideration to remedy these issues, and

Inform the public of the progress being made to implement the remedy. Table of Contents

Section Page

1.0 Overview of the Community Involvement Plan...... 4 2.0 Capsule Site Description...... 5 2.1 Site Histoiy...... 5 2.2 Site DescriptionLocation ...... 6 2.3 Site Inspections andCleanup .Activities...... 9 3.0 Community Background...... 11 3.1 Community Profile...... 11 3.2 History of Community Involvement...... 14 3.3 Key Community Concerns...... 14 3.4 Response to Community Concerns...... 14 3.5 Summaiy of Communication Needs...... 15 4.0 EP.A's Community Involvement Progmm...... 16 4.1 Tlie Plan...... 16 4.2 Time Frame Summaiy for Community Involvement .Activities...... 21

.Appendices: .A EP.A Regional Contacts...... 22 B Local Officials...... 23 C State Officials...... 24 D Federal Elected Officials...... 25 E Media Contacts...... 26 F Meeting Locations...... 28 G Repositoiy Locations...... 29 H Other Local Resources...... 30 I Fact Sheets...... 31

Figures: 1 Site Map...... 7 2 Regional Map...... 8 3 State Map...... 9 4 EJ Screen Map...... 13

Ram Leather Care Site Communin' Involvement Plan Page 3 September 2()18 Section 1.0 Overview of the C'ommunitv Involvement Plan

Tlie EPA developed this Community Involvement Plan (CIP) to tacilitate two-way communication between the community suirounding the Riim Leather Care Site (Site) and the EPA and to encourage community involvement in Site remediation activities. Tlie EPA will utilize the community involvement activities outlined in this plan to infonn area residents about the Site and provide opportunities for community involvement.

Tills CIP addresses the Site's relationship to the community and the EP.A (Section 2.0). provides a description of the community (Section 3.0). presents the EP.A's community involvement program (Section 4.0). iind provides a listing of resources available (.Appendices). The EP.A drew upon several inlbnnation sources to develop this plan, including community interviews and Site files. Tlie EP.A's Regional OtTice will oversee the implementation of the community involvement activities outlined in this Plan.

Ram Leather Care Site Communin' Involvement Plan Page 4 September 2()18 Section 2.0 C'apsule Site Description

2.1 Site History

Ram Leather Care operated as a dry cleaning iind leather restoration business from 1977 through 1993. Chlorinated hydrocarbon chemicals (primarily tetrachloroethylene (PCE)). and petroleum hydrocarbons (mineral spirits) were used in the cleaning and restoration processes. Concentrations of these chemicals and their breakdown products were detected in private wells on-site and in nearby otT-site wells, and in on-site soils.

In the pa.st. Riim Leather Care generated, stored, and disposed of luizardous substances and waste. \Va.stes generated at the Site were placed in metal dumpsters from 1977 until 1984. .Ai^er 1984. 55-gallon drums were used to store the wa.ste generated at the Site. During 1984-1988. wastes from the mineral spirits were stored in an above-ground wa.ste tank, supported by a concrete pad. for later otT-site recycling. In 1988. the company began storing hazardous waste on-site instead of shipping it otT-site for disposal or recycling.

On .April 6. 1991. the Mecklenburg County Department of Environmental Protection (MCDEP) discovered illegal open burning of filters containing PCE at the Site. Tlie facility was instructed to stop the burning iind complied. On .April 29. 1991. a state inspector discovered a 250-gallon above-ground storage tank of mineral spirit wa.ste and 49 drums of liquid wa.ste in an outside waste storage iu*ea. Tlie stoppers were open, allowing rainwater to enter the drum iind waste to overflow. Tlie drums were standing in liquid, indicating that some of the waste had been released onto the ground. .A composite siimple of the drum contents and a surface soil sample were tiiken on May 2. 1991. Stored on-site hiizardous wastes were shipped otT-site on June 14. 1991.

On .April 30. 1991. the North CiU'olina Division of Environmental Management (NCDEM). Water Quality Section, was notified of a boiler blow-otT in the storage area of Ram Leather Care. .A pennit had not been issued for the Site, making this an illegal discharge. Tlie area recently had been graded to allow surface water runofl'to flow toward .Albemarle Road. On May 6. 1991. MCDEP sampled one on-site drinking water well located within 50 feet of the storage area. Because of contiunination found in the well, the Ram Leather Care proprietor was advised to discontinue use of the well for drinking puiposes. On May 13. 1991. MCDEP sampled all otT-site drinking water wells within a half-mile of the Site. Siunpling data identified two private residential wells contaminated with chlorinated solvents.

.A series of investigations followed the May 1991 siunpling event. Drums, surface soil, surface water, the septic tank drain field, on-site wells, and additional otT-site wells were Siunpled over time.

Tlie Ram Leather Ciu*e dry cleaning and leather restoration facility is no longer in operation. Tlie owner filed for biinki'uptcy on MiU'ch 18. 1993. Most recently, the Site was used as a weekend flea market. .According to local otTicials. use of the Site as a flea market has been discontinued until further notice.

Ram Leather Care Site Communin' Involvement Plan Page 5 September 2()18 On Febriuu'y 16. 1994. the North Carolina DepiU'tment of Environment and Natural Resources (NCDENR) refeired the Site to the EPA for a possible removal action. On March 16. 1994. the EPA sampled on-site soil and wells and detennined that the contaminant levels were below removal action levels and assigned the Site a low priority for removal action. .A few months later, a nearby resident installed a new deep well for potable puiposes. Tlie North CiU'olina Department of Environmental Quality (NCDEQ). fonnerly NCDENR. sampled the new well on September 26. 1995. and found levels of PCE that exceeded the EP.A's removal action level for the contaminant. In November 1995. NCDEQ requested the EP.A reevaluate the Site for possible removal action. On May 4. 1996. the EP.A detennined the Site qualified for a high priority removal action. The Site was added to the National Priorities List (NPL) on September 29. 2003.

2.2 Site Description/Location

Tlie Site is located at 15100 .Albemarle Road. olT Route 27. situated in a rural iu*ea of eastern Mecklenburg County. North Carolina, approximately 15 miles east of downtown Charlotte iind six miles north of the Town of Mint Hill.

Tlie lacility was constructed in 1967 and housed a construction business until 1977. Ram Leather Care. Inc. operated at the Site as a dry cleaning iind leather restoration lacility from 1977 through 1993. Residential property surrounds the 10-acre Site. Privately owned parcels bound the Site in each direction. .A small fishing pond is located on the parcel to the south. .A gravel road running southeast from the driveway of the Site provides access to two residences to the south. Most of the area within a four-mile radius of the Site relies on private or community groundwater wells for drinking water. Public water from a source outside the Site vicinity serves a small area two to four miles east of the Site. .Approximately 7.900 people obtain their drinking water from wells within four miles of the Site.

Ram Leather Care Site Communin' Involvement Plan Page 6 September 2()18 Figure 1: Site Map

> ■* ^ ,

■s-- •*

^ ‘

■Hi’ 7^ jRa^^ther

uusaiuiiu * i,'"* «-V - «. • . •» -'V 5 ^ \ » J • V' - mriTiriN r-RAIN>El!D

Legend

- - - $eplic UN Sefitic D(4infl»W I i Rom LMin«r FKfNf^ Foimg CcncRte Pad

tso 300 Site Features •H Figure FfidI Ram Laattiar 8 He 1 Charlotte. Mecklenburg County. North Carolina NACeS state Plane NC. Feet

Ram Leather Care Site Community Involvement Plan Page 7 September 2018 Figure 2: Regional Map

A#--; •

Lowasvlk W Concord

© / Harnsbjrg @)

© Red Cross

'15100 AIMmarle Road Stanfrald Charlotte

o ©

Faiiview

Olive Brarrch Stallirgs IndUnTraK

® © > Weddington

Ram Leather Care Site Community Involvement Plan Page 8 September 2018 Figure 3: State Map

Cjnc^ati V -• Baltimore . I „ .Washington ^:v '' Poftnci ''s i , vV- ■ ® , * lA-' OELAt

viRafN.A sT- Lujtsville Frankfort 19 '’Lexington

EllraCMntown Richmond

KENTUCKY Roanoke VIRGINIA ^ Biacksburgo Petersburo' W tifewDoffhlews ' ling.GiSen , Daniel Boone ^“^""cVIrginiaBe >'''National Forest m

’*•* m - ‘c

Nantahala Charlotte Chattanooga National Forest Fayetteville ® Chattahoochee Greenville oSpananburg oRc^kHill Jacksonville National Forest Aidersonm

Alpharetta ^ — ' SOUTH Atanta t CAROLINA Myrtle Beadh' Ati(^sta 0 Talladega Nations Forest Summerville Macon Charleston)

GEORG A

2.3 Site Inspections and Cleanup Activities

In 1999, the EPA began the Remedial Investigation/Feasibility Study (RI/FS) at the Site. The EPA placed the Site on the NPL in 2003 because of contaminated groundwater and soil resulting from facility operations and waste handling practices. The EPA issued the Site’s interim cleanup plan in 2004.

In 2007, the EPA began cleanup activities, including digging up contaminated soil and disposing of it off-site. The EPA also conducted sampling of Site monitoring wells and nearby residential wells.

In 2008, the EPA completed soil cleanup activities and installed the groundwater pump-and-treat system. The EPA began additional soil and groundwater sampling as part of the Site’s remedial investigation. The EPA also connected nearby residents to the public water supply.

From 2008 to 2011, the EPA conducted operation and maintenance activities for the groundwater pump-and-treat system. The system operated until 2011, when the EPA shut the system down to perform RI/FS activities in preparation for the Site’s final cleanup.

Ram Leather Care Site Community Involvement Plan Page 9 September 2018 Groundwater samples were collected from monitoring wells on seven occasions between 2007 and 2016: from private wells in 2007 and 2010, and from the bedrock pumping well in 2007 and 2011.

In 2013, the EPA completed the building demolition activities at the Site in order to conduct a thorough Remedial Investigation of the remaining contamination on the site. The EPA has also conducted an electrical resistivity imaging of the top of competent bechock. The REFS was completed in 2018 and the details were presented to the community in a public meeting during a 30-day comment period.

The Remedial Investigation (RI) report focused on contamination in Site soil and shallow ground water. Based on the findings of the report, the EPA determined that remedial actions are required to ad(h'ess Site contamination. EPA’s preferred cleanup plan will address soil and groundwater contamination on the Site. The interim remedy will include soil vapor extraction, thermal treatment and a biobarrier (chemical injections). The soil vapor extraction system will be used to adless contamination in the soils. Vacuum blowers are installed to increase movement of the contamination throughout the soil to collection wells. The vapors are extracted and pass through to collection wells and treated to remove contaminants. The in situ thermal treatment remedy will treat approximately 9,000 square feet of area by heating the temperature of the subsurface to approximately 100°C. Extracted contaminated groundwater will pass through a system to remove contaminants prior to disposal through a deep injection well. Extracted vapors will be treated. The biobarrier will be created by injecting a carbon substrate such as emulsified oil from wells into the groundwater. Contaminants in groundwater will be destroyed as they pass through the barrier. Institutional controls will be placed on the property to limit use of the land and groundwater, in order, to prevent further exposure. Based on the 2017 residential well sampling results, as a precautionary measure, the existing water line will be extended eastward along Alvin Hough Road to provide municipal water to private residents.

Ram Leather Care Site Community Involvement Plan Page 10 September 2018 Ram Leather Care Site Communin' Involvement Plan Page 11 September 2()18 Section 3.0 C'ommunitj Background

3.1 C'ommunit\ Profile

Mecklenburg County is located in the southwestern pail of North Carolina on the South Carolina border. It is the most populous county in the state with more than one million residents iind serves as a hub for nuiny large businesses. Mecklenburg County's amenities include parks, recreational tacilities. libmi'ies. cultural centers, and professional sporting events. Mecklenburg County is served by the Charlotte Douglas International .Aiiport.

Charlotte is Mecklenburg County's most populous city and its county seat. Between 2004 iind 2014. Charlotte was mnked as the countiy 's fastest growing metropolitan area and is the second largest city in the southeastern Ihiited States iind the third fastest growing major city in the Ihiited States. The city is home to the coiporate headquarters of Bank of .America and the ea.st coast operations of Wells FiU'go. which along with other financial institutions made it the second-largest biinking center in the Ihiited States from 1995 to 2017. iind the third largest from 2017 to the present.

Tlie Site is located six miles north of the Town of Mint Hill, a major suburb of Charlotte in Mecklenburg County. Mint Hill is 21.3 square miles and is located approximately 13 miles southeast of downtown Charlotte. It has a population of more than 26.000 residents.

.Approximately 1.000 people live within one mile of the Ram Leather Care Site and approximately 319 housing units exist within the one-mile iu*ea.

Tlie Site repositoiy is located at the Mint Hill Branch LibriU'y. Meeting locations in the area include Independence High School. Clear Creek ElementiU'v. and Charlotte Mecklenburg Libran - Mint Hill.

Ram Leather Care Site Communin' Involvement Plan Page 12 September 2()18 Deinognipliics and mfonnation: Mecklenburg County, NC

Population: 1.054.835

Mecklenburg County inedian age: 33 \ears

North Carolina inedian age: 38 \ears

Mecklenburg County estimated median household mcoine ui 2016: S50.579

Mecklenburg Comity estunated per capita mcoine ui 2016: S27.352

Race/Etimic Backgromid:

White: 64.02**o | Black: 27.87**o | Hispanic: 6.45**o | Two or more races: 1.55**o | Asian: 3.15**o

Education:

High school graduate or higher: 89.6®o

Bachelor's degree or higher: 43.1®o

Ram Leather Care Site Communin' Involvement Plan Page 13 September 2()18 EJSCREEN Report (Version 2018) 1 mile Ring Centered at 35.228057,-80.606803 NORTH CAROLINA, EPA Region 4 Approximate Population: 1,213 Input Area (sq. miles): 3.14

Figure 4: EJ Screen Map

1:36,112 March 26. 2010 Buffer Area ■ Superfund ^ ftojed 2 sa

EPA State Percentile Percentile in USA Percentile in Selected Variables Value Region Average in State EPA Region Average USA Average

Demographic hidicators Demographic hidex 22% 37% 26 38% 25 36% 34 Minoritv Population 19% 36% 34 37% 36 38% 38 Low Income Population 24% 38% 26 39% 26 34% 37 Linguistically Isolated Population 4% 3% 77 3% 74 5% 67 Population with Less Than High 6% 14% 28 14% 26 13% 33 School Education Population under Age 5 4% 6% 30 6% 31 6% 29 Population over Age 64 15% 14% 59 15% 58 14% 61

3.2 History of Community Involvement

Ram Leather Care Site Community Involvement Plan Page 14 September 2018 On May 25, 2004, the Agency for Toxic Substances and Disease Registry (ATSDR) held two public availability sessions at the Mint Hill Town Hall. Representatives from the EPA, Mecklenburg County Health Department, and MCDEP were in attendance.

The EPA conducted interviews with residents in the community in May 2018, to gather information to revise the Community Involvement Plan. A public meeting was held to discuss the details of a plan that EPA was proposing to adless the onsite contamination on May 22, 2018, at the Fellowship Baptist Church at 11416 Albemarle Road, Mint Hill, North Carolina. EPA notified the community through distributing a fact sheet to the mailing list, public notice in The Charlotte Observer and the EPA web page for the Site.

The EPA and NCDEQ have provided information regarding the cleanup of the Site to the public through fact sheets, public meetings, announcements in The Charlotte Observer, and the Administrative Record file. In addition. Site and Superlund activities that have been conducted at the Site are available for review in the Administrative Record/Information Repository at the Charlotte Mecklenburg Library-Mint Hill.

3.3 Key Community Concerns

The community has always been concerned about the groundwater contamination from the site migrating to the surrounding private wells that are used for drinking water purposes. EPA has been monitoring private wells within a mile radius of the Site since 2007.

3.4 Response to Community Concerns

EPA will continue to monitor the residential wells throughout the cleanup process. If there are property owners within a mile radius of the site, that would like their well sampled, they have been asked to contact the Community Involvement Coordinator (CIC) and provide the appropriate information for the sampling. After the sampling has been conducted and the data has been verified, result letters are provided to the property owners with the opportunity to speak one-on-one with an EPA representative, if needed. The CIC will continue to work with residents and community members to provide up-to-date information about the ongoing remedial activities and cleanup efforts at the Site.

Ram Leather Care Site Community Involvement Plan Page 15 September 2018 3.5 Summary of C'ommunication Needs

Tlie best way to communicate with the nearby community is for the EPA to continue to host public meetings and send flyers tlu'ough the mail. The newspaper is also a good source to communicate to the residents. The Mint Hill Times is the primaiy paper that reaches the community in Mint Hill. Tuesday and Thursday evenings are the best times for the EP.A to host public meetings, either at the local repository, at Eellowship Baptist Church, or other available venues (see .Appendix E). Residents have contact infonnation for the Site's CIC and RPM and are encouraged to contact them should they have questions and concerns about the Site iind the ongoing remedial activities and cleanup process.

Ram Leather Care Site Communin' Involvement Plan Page 16 September 2()18 Section 4.0 EPA’s C'ommunitj Involvement Program

Tlie overall goal of the EPA's community involvement progmm is to promote two-way communication between citizens and the EPA and to provide opportunities for meiiningful and active involvement by the community in the cleanup process. Tlie EPA will implement the community involvement activities described below. Tlie following plan is based on the results of the community interviews described earlier. Tlie plan addresses each issue that was identified as important to the community.

4.1 The Plan

Issue 1: Keeping the public infonned and up to date.

Acti\ity lA: Designate an EPA Conuiiuiiity In\ohenient Coordinator (CIC).

• Objective: To provide a primaiy liaison between the community and the EP.A. iind to ensure prompt, accurate, and consistent responses and infonnation dissemination about the Site. In those instances, where the EP.A's CIC may be unable to provide adequate infonnation (such as on teclmical issues), inquiries will be directed to the appropriate EP.A contact.

• Method: The EP.A has designated an EP.A CIC to handle Site inquiries and serve as a point of contact for community members. The CIC was appointed by the Region 4 Superfund Division. .Angela Miller is the EP.A CIC assigned to the Site. She works closely with Beverly Stepter. the EP.A's Remedial Project Manager (RPM) for the Site.

• Timing: Tlie cuirent CIC has been designated to provide community support.

.\cti\1ty IB: Prepare and distribute Site fact sheets and teclmical suininaries.

• Objective: To provide citizens with cuirent. accurate, easy-to-read, easy-to-understand infonnation about the Site.

• Method: Pact sheets iu*e mailed to all piulies on the Site mailing list. In addition, copies are available at the infonnation repositories (see .Appendix G) and other locations as identified by the community.

• Timing: Tlie EP.A will continue to prepare and distribute tact sheets to inform the communitv on iin as needed basis.

Ram Leather Care Site Communin' Involvement Plan Page 17 September 2()18 Acti\ity 1C: Pro\icle a toll-free ‘‘800 number" for the comniuiiity to contact the EPA.

• Objective: To enable citizens to obtain the latest inlbnnation available whenever they want, rather than having to wait for a meeting or a fact sheet, iind without incuiring iiny cost.

• Method: The EPA has activated the 800 number iind publishes the number periodically in the local papers and in all tact sheets.

• Timing: Tlie toll-free number is cuirently operational (1-877-718-3752).

.\cti\ity ID: Mamtam a inailmg list for the Site.

• Objective: To facilitate the distribution of site-specific infonnation to eveiy one who needs or wants to be kept inlbnned about the Site.

• Method: The EP.A has created a mailing list that includes all residences adjacent to the Site, in known or suspected paths of migration, or those othenvise atTected by the Site. Tlie EP.A will also solicit interested parties via tact sheets, newspaper articles, public meetings, public availabilities, etc.

• Timing: Tlie EP.A has developed the Site mailing list and reviews iind or revises the list periodically to keep it cuirent.

.\cti\1ty IE: Establish and niaintam Inforniation Repositories.

• Objective: To provide a convenient location for residents to review and copy otTicial documents iind other pertinent infonnation about the Site iind EP.A activities.

• Method: The repositoiy is a reference collection of Site infonnation containing the .Administrative Record file, other site-specific infonnation. the CTP. resource infonnation and the general Superfund process. The CTC will work with a local contact to establish the local repository. Tliis repository will be accessible to the physically challenged, will have copier facilities, and will be available to residents during noniial business hours iind at least some evening and or weekend hours.

• Timing: Tlie EP.A established the Infbiniation Repositoiy at the Charlotte Mecklenburg Library - Mint Hill. 6840 Mathews-Mint Hill Road. Charlotte. NC 28227. Tlie EP.A will continue to provide additional documents as they become available.

Ram Leather Care Site Communin' Involvement Plan Page 18 September 2()18 Activity IF: Provide Site information on the Internet.

• Objective: To provide key resources for searching and listing both general and specific information about hazardous waste issues.

• Method: A Site Status Summary for this Site and information about the EPA can be found at https://www.epa.gov/superfund/Ram-Leather-Care ■ EPA Headquarters: https://www.epa.gov ■ EPA Region 4: https://www.epa.gov/aboutepa/about-epa-region-4-southeast ■ EPA Region 4: 61 Forsyth Street SW, Atlanta, GA 30303

• Timing: Site status summaries are periodically updated.

Activity IG: Provide Technical Assistance Grant (TAG) information.

• Objective: To provide resources for community groups to hire technical advisors to assist them in interpreting technical information about the Site.

• Method: The EPA will provide information about the TAG to affected communities. The EPA will provide qualified group(s) TAG applications and assistance in completing the application.

• Timing: The EPA will provide options for technical assistance resources throughout the Superfund process.

Activity IH: Maintain the Administrative Record.

• Objective: To provide residents with a paper trail of all documents, resources, etc. used by the RPM and Site Team to make decisions about the Site and its cleanup.

• Method: The EPA has provided two sets of the Administrative Record for the Site: one in the EPA Region 4 offices located at 61 Forsyth Street SW, Atlanta, GA 30303, and one located in the local Information Repository near the Site.

• Timing: The Achninistrative Record is opened as soon as Site investigation begins and remains open until the Site is deleted from the National Priorities List (NPL).

Ram Leather Care Site Community Involvement Plan Page 19 September 2018 Issue 2: Pro\ ide adequate and nieanuigful oppoi*tuiiities for coniniunity ui\oh einent.

Acti\ity 2A: Hold public ineetuigs.

• Objective: To update the community on Site developments and address community questions, concerns, ideas, and comments.

• Method: Refer to Appendix F for suggested meeting locations. Tlie EP.A will continue to schedule, prepare for. and attend all announced meetings. Tlie EP.A will provide at least two weeks prior notice of the scheduled meeting. Tlie RPM. CTC. and other appropriate EPA statT will attend.

• Timing: Tlie EP.A holds public meetings as required by the National Contingency Plan and as needed with the community.

.\cti\ity 2B: Encourage forination of a Coniinuiiity .\d\ ison Group (C.\G).

• Objective: To assist citizens with a meaningful way to become actively involved in the Site cleanup process, iind to provide the Site Team with a viable means of learning citizen concerns iind attitudes.

• Method: The EP.A may provide inlbnnation about the fonnation of a C.AG. If fonned. the EP.A may provide administrative support but will not be an active member.

• Timing: Tlie EP.A will respond to iiny requests for assistiince to fonn a C.AG. if Stakeholder interests show support. Infonnation will be provided as needed.

.\cti\ ity 2C: Make inforinal \ isits to the conununity.

• Objective: To help keep community members infonned about the Site, while providing the EP.A with feedback about Site activities iind the community's opinions.

• Method: The EP.A has established a presence in the community tlu'ough inlbmial. often unscheduled visits to talk spontiineously with local residents.

• Timing: Tliroughout the entire cleiinup process.

.\cti\ity 2D: Solicit coninients during a Public Coiiuiieiit Period.

• Objective: To give community members iin opportunity to review iind comment on viu'ious EP.A documents. Tliis provides the citizens with meaningful involvement in the process and also provides the Site Team with valuable infonnation for use in making decisions.

Ram Leather Care Site Communin' Involvement Plan Page 2() September 2()18 • Method: The EPA will announce each comment period separately. .Announcements will appeiu* in local newspapers and EP.A tact sheets: they will include particulars on duration, how to make comments, where to submit comments, etc. Tlie EP.A may solicit comments on the following inlbnnation driift documents: driil't CTP. draft summary of test results (not individual tests) and initial inteipretation. preliminaiy findings on the RI and a list of possible remedies likely to be considered, preliminaiy findings of the PS and a brief sumniiii'y of the leading contender for the proposed remedy, iind preliminaiy phins for implementation iind construction.

• Timing: Comment periods will be announced as appropriate.

.\cti\ity 2E: Prepare and issue a Respoiisi\eiiess Suiiiiiian.

• Objective: To summarize comments received during comment periods, to document how the EP.A has considered those comments during the decision-making process, and to provide responses to major comments.

• Method: The EP.A will prepare a Responsiveness Sumniiii'y as a section of the ROD. The Responsiveness Sumniiii'N will include four sections: 1. Overview: 2. Background on Community Involvement: 3. Summan of comments received and EP.A responses: 4. Remedial Design Remedial .Action concerns. .All infonnation. both technical and nonteclmical. will be conveyed in a manner that is easily understood.

• Timing: Tlie EP.A issues the Responsiveness Summan as part of the ROD.

.Acti\ity 2F: Re\ ise the Coniinuiiity hi\ oheiiieiit Plan (CTP).

• Objective: To identify and address community needs, issues, or concerns regarding the Site or the cleanup remedy that are not cuirently addressed in this CTP.

• Method: The Revised CTP will update the infonnation presented in the previous version of the CTP.

Timing: Tlie EP.A revises the CTP as community concern wairants or at least even three years until the Site is no longer active.

Ram Leather Care Site Communin' Involvement Plan Page 21 September 2()18 4.2 Time Frame Summary for Community Involvement Activities

ACTIVITY TIME FRAME

Designate an EPA Community Involvement Designated; Angela Miller Coordinator (CIC) Prepare and distribute Site fact sheets and As needed technical summaries Provide a toll-free “800 number” for the Currently in operation community to contact the EPA Maintain a mailing list for the Site Ongoing

Establish and maintain Information Repositories Established; update as needed

Provide Site information on the Internet Currently available; update as needed Provide Technical Assistance Grant (TAG) Ongoing information Maintain the Administrative Record Update as needed

Hold public meetings As needed Encourage formation of a Community Advisory Ongoing Group (CAG) Make informal visits to the community As needed Solicit comments during a Public Comment As needed and required Period Prepare and issue a Responsiveness Summary Following public comment periods

Revise the Community Involvement Plan (CIP) As needed, at least every 3 years

Ram Leather Care Site Community Involvement Plan Page 22 September 2018 Appendix A EPA Regional Contacts

Beverly Stepter Angela Miller Remedial Project Manager Community Involvement Coordinator U.S. EPA, Region 4 U.S. EPA, Region 4 61 Forsyth Street SW 61 Forsyth Street SW Atlmita, GA 30303 Atlanta, GA 30303 (404)562-8816 (404)562-8561 [email protected] [email protected]

Ram Leather Care Site Community Involvement Plan Page 23 September 2018 Appendix B Local Officials

Mayor Ted Diggers 4430 Mint Hill Village Lane Mint Hill, NC 28227 (704) 545-9726 [email protected]

Town Commissioners Mike Cochrane 4430 Mint Hill Village Lane Mint Hill, NC 28227 (704) 545-9726 [email protected]

Dale Dalton 4430 Mint Hill Village Lane Mint Hill, NC 28227 (704) 545-9726 [email protected]

Richard Newton 4430 Mint Hill Village Lane Mint Hill, NC 28227 (704) 545-9726 [email protected]

Carl Ellington 4430 Mint Hill Village Lane Mint Hill, NC 28227 (704) 545-9726 [email protected]

Ram Leather Care Site Community Involvement Plan Page 24 September 2018 Appendix C State Officials

State Governor Roy Cooper North Carolina Office of the Governor District 39 20301 Mail Service Dan Bishop Raleigh, NC 27699-0301 North Carolina Senate (919)814-2000 16 West Jones Street, Room 2108 https://govemor.nc.gov/contact/contact- Raleigh, NC 27601 govemor-cooper (919)733-5655 [email protected] Lieutenant Governor Dan Forest District 40 310 North Blount Street Joyce Waddell Raleigh, NC 27601 North Carolina Senate (919)814-3680 16 West Jones Street, Room 1113 https://ltgov.nc.gov/ Raleigh, NC 27601 (919)733-5650 State House of Representatives [email protected] District 103 - Mecklenburg William Brawley District 41 300 North Salisbury Street, Room 534 Jeff Tarte Raleigh, NC 27603 North Carolina Senate (919) 733-5800 300 North Salisbury Street, Room 623 [email protected] Raleigh, NC 27603 (919)715-3050 State Senators [email protected] District 37 Jeff Jackson North Carolina Senate 16 West Jones Street, Room 1104 Raleigh, NC 27601 (919)715-8331 [email protected]

District 38 JoelD. M. Ford North Carolina Senate 300 North Salisbury Street, Room 520 Raleigh, NC 27603 (919) 733-5955 [email protected]

Ram Leather Care Site Community Involvement Plan Page 25 September 2018 Appendix D Federal Elected Officials

U.S. Senate U.S. House of Representatives

Richard Burr Robert Pittinger, District 9 Washington D.C. Office 224 Cannon House Office Building United States Senate Washington, DC 20515 217 Russell Senate Offiee Building (202) 225-1976 Washington, DC 20510 https://pittenger.house.gov (202) 224-3154 https://www.burr.senate.gov/ Charlotte District Office 5970 Fairview Road, Suite 430 Winston-Salem Office Charlotte, NC 28210 2000 West Street, Suite 508 (704) 362-1060 Winston-Salem, NC 27104 (336)631-5125

Thom Tillis Washington D.C. Offiee United States Senate 185 Dirksen Senate Office Building Washington, DC 20510 (202) 224-6342 https://www.tillis.senate.gov

Charlotte Offiee 9300 Harris Comers Parkway, Suite 170 Charlotte, NC 28269 (704) 509-9087

Ram Leather Care Site Community Involvement Plan Page 26 September 2018 Appendix E Media Contacts

Television Stations: Radio Stations:

WBTV-CBS WFAE FM: Public Radio 1 Julian Price Place 8801 J.M. Keynes Drive, Suite 91 Charlotte, NC 28208 Charlotte, NC 28262 (704) 374-3500 (704) 549-9323 http://www.wbtv.com/ http://wfae.org/

WCCB - CW WNKS 95.1 FM 1 Television Place 1520 South Blvd., Suite 300 Charlotte, NC 28205 Charlotte, NC 28203 (704)372-1800 (704) 522-1103 http ://www.wccbcharlotte.com/ http ://kiss951 .com/

WCNC-NBC WXRC 95.7 FM 1001 Woodbridge Center Drive 1666 Radio Station Road Charlotte, NC 28217 Newton, NC 28658 (704) 329-3636 (828) 464-4041 http://www.wcnc.com/ http: //ww w .957theride .com/

WJZY-FOX WJBT 96.1 FM 3501 Performance Road 801 Wood Ridge Center Drive Charlotte, NC 28214 Charlotte, NC 28217 (704) 398-0046 (704) 714-9444 http://www.fox46charlotte.com/ https://channel961.iheart.com/

WSOC-ABC WPIR 88.1 FM 1901 North Tryon Street PO Box 25775 Charlotte, NC 28206 Winston-Salem, NC 27114 (704) 335-4738 (336) 788-1155 http ://www.wsoctv.com/ https://www.iovfm.org/

WTVI-PBS WOSF 105.3 FM 3242 Commonwealth Ave. 8809 Lenox Pointe Drive, Suite A Charlotte, NC 28235 Charlotte, NC 28273 (704) 330-5942 (704) 548-7800 http://www.wtvi.org https ://oldschool 1053. com/

WRHM 107.1 FM 142 N. Confederate Avenue Rock Hill, SC 29730 (803) 324-1071 http ://www.wrhi.com/wrhm/

Ram Leather Care Site Community Involvement Plan Page 27 September 2018 WBT 1110 AM 1900 Julian Price Place Town of Mint Hill Facebook Charlotte, NC 28208 https://www.facebook.com/minthillnc (704) 374-3600 http://www.wbt.com/ Town of Mint Hill Twitter https://twitter.com/TownQfMintHill WFGW 106.9 3 Porters Cove Road City of Charlotte Facebook Asheville, NC 28805 https://www.facebook.com/CLTgov (828) 285-8477 https://1069thelight.org/ City of Charlotte Twitter https://twitter.com/CLTgov Newspapers;

The Charlotte Observer 550 South Caldwell Street Charlotte, NC 28203 (704)358-5000 http://www.charlotteobserver.com/

The Charlotte Post 5118 Prineess Street Charlotte, NC 28269 (704) 376-0496 http://www.thecharlottepost.com/

The Mint Hill Times 7319 Matthews-Mint Hill Road Charlotte, NC 28227 (704) 573-4606 https://www.minthilltimes.com/

Matthews-Mint Hill Weekly PO Box 1104 Matthews, NC 28106 (704) 849-2261 http ://matthewsminthillweekly.com/

Social Media;

Mecklenburg County Facebook https://www.facebook.com/MecklenburgCountv

Mecklenburg County Twitter https://twitter.com/MeckCounty

Ram Leather Care Site Community Involvement Plan Page 28 September 2018 Appendix F Meeting Locations

Independence High School 1967 Patriot Drive Charlotte, NC 28227 (980) 343-6900

Clear Creek Elementary 13501 Albemarle Road Charlotte, NC 28227 (980) 343-6922

Charlotte Mecklenburg Library-Mint Hill 6840 Matthews-Mint Hill Road Charlotte, NC 28227 (704)416-5200

Fellowship Baptist Church 11416 Albemarle Road Mint Hill, NC 28227 (704) 545-9668 www.Fbccharlotte.com

Ram Leather Care Site Community Involvement Plan Page 29 September 2018 Appendix G Repository Locations

Local Repository: EPA Region 4 Repository:

Charlotte Mecklenburg Library-Mint Hill U.S. Environmental Protection Agency 6840 Mathews-Mint Hill Road 61 Forsyth Street SW Charlotte, NC 28227 Sam Nunn Atlanta Federal Center, 9* Floor (704)416-5200 Atlanta, GA 30303 https://www.cmlibrary.org/branch/mint-hill (404)562-8190 R4-librarv@epa. gov 8:00am-4:30pm Monday-Friday

Ram Leather Care Site Community Involvement Plan Page 30 September 2018 Appendix H Other Local Resources

North Carolina Department of Environmental Quality - Mooresville Regional Office 610 East Center Avenue, Suite 301 Mooresville, NC 28115 (704) 663-1699 https://deq.nc.gov/contact/regional-offices/mooresville

Mecklenburg County Health Department 249 Billingsley Road Charlotte, NC 28211 (704) 336-4700 [email protected]

Mecklenburg County Environmental Health Department 700 North Tryon Street, Suite 208 Charlotte, NC 28202 (704)336-5100 [email protected]

Town of Mint Hill 4430 Mint Hill Village Lane Mint, Hill, NC 28227 (704) 545-9726 http://www.minthill.com/

City of Charlotte Charlotte-Mecklenburg Government Center 600 East 4*“^ Street Charlotte, NC 28202 (704) 336-7600 http ://charlottenc. gov

Ram Leather Care Site Community Involvement Plan Page 31 September 2018 Appendix I Fact Sheets

PROPOSED PLAN for INTERIM RECORD OF DECISION RAM LEATHER CARE SITE CHARLOTTE, MECKLENBURG COUNTY, NORTH CAROLINA 1^1 MAY 2018

This Proposed Plan is not to be considered a technical document but has been prepared to provide an abridged summary to the public.

You are Invited to Comment on this Proposed Cleanup for the Ram Leather Care Site, Charlotte, NC

The United States Environmental Protection Agency (EPA or Agency) is issuing this Proposed Plan to present EPA’s Preferred Remedial Alternative for the Ram Leather Care Site (Site) Interim Record of Decision (IROD) which addresses soil and groundwater contaminated with chlorinated ethene compounds. This Proposed Plan describes the remedial alternatives evaluated in the 2016 Feasibility Study, identifies the Agency’s Preferred Remedial Alternatives, and presents the rationale EPA used to select the Preferred Alternatives. The Preferred Alternative for this interim action is:

• Unsaturated Zone (UZ) Alternative UZ #2 - Soil Vapor Extraction (SVE); • Main Source Area (MSA) Alternative MSA #4 - /n Situ Thermal Treatment; • Secondary Source Area (SSA) Alternative SSA #4 - In Situ Thermal Treatment; • Municipal water line extension Option #3; and • Institutional Controls (ICs) in the form of the State of North Carolina Declaration of Perpetual Land Use Restrictions (DPLURs).

Contamination at depth within the bedrock aquifer and off-site within the dilute plume will be addressed as part of the final remedy for the Site.

The EPA, the lead agency, is issuing this Proposed Plan in consultation with the North Carolina Department of Environmental Quality (NCDEQ), the support agency, as part of its public participation responsibilities under Section 117 (a) of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 as amended (CERCLA of Superfund), 42 U.S.C. § 9617(a) and Section 300.435(f)(2) of the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). This Proposed Plan summarizes and identifies key information that can be found in greater detail in the Remedial Investigation (RI) and Feasibility Study (FS) documents, and other documents contained in the Administrative Record file for this Site. The Administrative Record and Information Repository can be found in the Mint Hill Branch Library, 6840 Matthews - Mint Hill Road, Mint Hill. North Carolina and in EPA's, Region IV Information Center at 61 Foreyth Street, SW, Sam Nunn Atlanta Federal Center, Atlanta, Georgia.

Implementation of the Preferred Alternative, or another cleanup alternative described in this Proposed Plan, is considered necessary to protect human health and the environment fi-om actual or threatened releases of hazardous substances. The NCDEQ has expressed support for the Preferred Alternative. The EPA, in consultation with the NCDEQ, will select an interim remedy after the public comment period has ended and the comments received during the comment period have been reviewed and considered. Based on new information and/or comments received on the Preferred Alternative, the selected interim remedy may be different fi’om the Preferred Alternative presented in this Proposed Plan. The public's comments will be considered and discussed in the responsiveness summary of the IROD, which will document the EPA’s selected interim remedy for the Site.

The EPA and the NCDEQ encourage the public to review these documents to gain a more comprehensive understanding of the Site and the Superfund activities that have been conducted. To ensure the community’s concerns are being addressed, a pubhc comment period lasting 30 calendar days will be held. During this time.

Ram Leather Care Site Community Involvement Plan Page 32 September 2018 Proposed Plan for ROD 2 Rm Leather Care Site May 2018 the public is encouraged to submit comments to the EPA on this Proposed Plan and the alternatives presented. The EPA will hold a public meeting on Tuesday, May 22,2018, at 6:00 PM at the Fellowship Baptist Church at 11416 Albemarle Road in Mint Hill, NC. Comments can be submitted at the public meeting, through the mail, via facsimile, or email. Please refer to the text box below titled “Tell Us What You Think” for additional details on submitting comments and community participation. You have until Wednesday, Jime 13,2018, to submit written comments on this Proposed Plan.

You are encouraged to submit your comments during the public comment period. Your input on this Proposed Plan is an important part of the decision-making process. We want to hear from you and will consider your comments in making the final decision.

Tell Us What You Think Public Comment Period Attend the Public Meetine Locations of Administrative Record and May 15 through June 13, 2018 Information Renositorv You are invited to attend a public EPA will accept written comments on meeting sponsored by EPA to hear Mint Hill Branch Library this Proposed Plan during the public about this Proposed Plan. At the 6840 Matthews - Mint Hill Road comment period. You may submit meeting you will be able to voice MintHiU,NC 28227 written comments three (3) ways: your views about the cleanup. Phone: 704-416-5200 BY MAIL Hours; Mon. - Thurs. 9 a.m. - 8p.m. The meeting will be held: Beverly Stepter Fri., Sat. 9 a.m. - 5 p.m. U.S. EPA - Region 4 Sun. Closed Tuesday, May 22,2018 61 Forsyth Street, SW from 6:00 - 8:00 p.m. EPA, Region 4's Information Center; 61 Atlanta, Georgia 30303-3104 Location: Forsyth Street, SW BY EMAIL Sam Nunn Atlanta Federal Center [email protected] Atlanta, Georgia 30303 Fellowship Baptist Church BY FACSIMILE 11416 Albemarle Road Phone: 404-562-8946 404-562-8816 Mint Hill, NC 28227 Hours: Mon - Fri, 8 a.m. - 5 p.m. Atklressed to Beverly Stepter

Community Involvement Plan Page 33 September 2018 Proposed Plan for ROD i Rm Leather Care Site May 2018 INTRODUCTION

This Proposed Plan provides:

• a brief description and history of the Site; • a summary of the nature and extent of contamination; • a summary of the Baseline Risk Assessment; • a summary of cleanup technologies that were considered and evaluated by the EPA; • a description of what the proposed site cleanup is expected to accomplish; • a list of cleanup levels for the chemicals of concern; • the Agency’s Preferred Alternative; and • a list of contacts and locations for more information.

SITE HISTORY

Ram Leather Care is located on 10 acres of land at 15100 Albemarle Road, four miles from Charlotte in Mecklenburg County, NC (Figure 1). The site coordinates are latitude 35° 13’ 55” N and longitude 80° 36’ 09” W. Access to the property is provided by an asphalt driveway from Albemarle Road that leads south over railroad tracks into the Ram Leather Care Site where the driveway is gravel.

The Ram Leather Care parcel is primarily surrounded by residential and forested properties. Other privately owned parcels occur to the east, north, and west. The gravel road continues southeast from the Ram Leather Care driveway providing access to two residences. One large operations building existed on the property, however most of the building was demolished in 2012, the overall building footprint is outlined by the existing concrete slab which was not removed (Figure 2).

Ram Leather Care is a former dry cleaning facility. The Ram Leather building, which was constmcted in 1967, housed a construction business until 1977. Thereafter, Ram Leather Care restored leather goods and operated as a dry cleaning facility from 1977 to 1993. Chlorinated ethenes, primarily tetrachloroethene (PCE), and petroleum hydrocarbons (mineral spirits) were used in the cleaning process. The site was added to the National Priorities List (NPL) on September 29, 2003.

Studies at the Ram Leather Care Site were initiated by the owner in 1991 and the EPA began investigations in 1994 at the request of the NCDEQ. The EPA conducted several investigations at the Site between 1994 and 2006. These investigations identified various chlorinated ethene compounds as primary contaminants in soil and groundwater at the Site. PCE, the primary chlorinated ethene compound used at the site, degrades to trichloroethene (TCE), cis-l,2-dichloroethene (cDCE), 1,1-dichloroethene (DCE), and vinyl chloride (VC), which also are present in Site soil and groundwater. Contamination also was identified in a few residential wells screened within the bedrock aquifer around the Ram Leather Care property and these residents were coimected to a municipal water line in 2004; the impacted residential wells were abandoned in 2008.

The EPA issued an IROD in 2004 to address soil and groundwater contamination at the Site. In 2008, EPA completed soil cleanup activities which consisted of excavating 2,400 cubic yards of soil to the approximate depth of the water table (about 18ft below the surrounding land surface) from the area of most severe contamination, and installation of a groundwater pianp-and-treat system. The purap-and-treat system was shut down in 2011 after it was determined that the construction of the pumping well, which included a long screen interval, was increasing contaminant concentrations in the deeper portions of the bedrock aquifer.

The EPA conducted additional RI/FS studies from 2010 to 2016 to better characterize the extent of contamination at the Site and to support development of a Site-wide remedial strategy. This work included

Community Involvement Plan Page 34 September 2018 Proposed Plan for ROD 4 Ram Leather Care Site May 2018 installing additional monitoring wells to various depths beneath the site; sampling of subsurface soil, groundwater and surface water; pilot testing to determine the feasibility of removing contamination using soil vapor extraction; characterizing the subsurface using electrical resistivity imaging (ERI); high resolution sampling of the shallow subsurface using a Membrane Interface Probe-Hydraulic Profiling Tool (MiHPT); searching for buried drums using ground penetrating radar (GPR); and vertical profiling of groundwater during installation of monitor well borings. The results of these investigations were presented in the 2016 Remedial Investigation Addendum report. The RI Addendum report evaluated;

• 2007 groundwater data • 2008 groundwater and subsurface soil data • 2010 groundwater and subsurface soil data • 2011 groundwater and surface water data • 2013 groundwater data • 2014 and 2015 subsurface soil data • 2015 groundwater data • 2016 soil and groundwater data

SITE CHARACTERISTICS

Nature and Extent of Soil Contamination Subsurface Soil One hundred and fifty-six subsurface soil samples were collected between 2008 and 2016 from depths ranging from 1.5 to 62 ft below ground (Figure 3). Excluding samples in which chlorinated ethene contaminants were reported as non-detected at detection limits exceeding the preliminary soil remediation goal (PRO), 48 percent of samples (75 of 156) contained PCE in concentrations above the PRO and 17 percent of samples (27 of 156 samples) contained vinyl chloride in concentrations above the PRG. Ten percent of samples (16 of 156) exceeded the PRG for cis-l,2-DCE, 9 percent (14 of 157 samples) exceeded the PRG for TCE, and 0.6 percent (1 of 156 samples) exceeded the PRG for 1,1-DCE. The extent of PCE contamination in soil is shown on Figure 4.

The 2014 MiHPT investigation identified possible chlorinated ethene contamination beneath the former Ram Leather building, adjacent to the building to the south and southeast, and west of the former building and soil excavation area. The MiHPT investigations showed this contamination is discontinuously present between about 15 and 28 ft depth; deeper contamination that may be present could not be investigated by the MiHPT due to the characteristics of the subsurface, which could not be penetrated with the drilling rig used in the investigation.

Neither the western boundary nor the vertical extent of subsurface soil contamination have been fully delineated. Contaminants were not detected above the soil PRG in subsurface soil samples collected fiom two borings (SB29 and SB30) near the western property boundary. Eight of ten soil samples collected between 50 and 62 ft bis contained PCE in concentrations Aat exceed the soil PRG for groundwater protection. Although contamination of the entire soil and saprolite column has not been demonstrated, PCE contamination is present in the hydrogeologic transition zone and within 12 ft of the top of fractured, metamorphic bedrock. Consequently, contamination is likely to have migrated down to the top of bedrock in at least a few locations. A similar conclusion does not appear to apply to TCE, vinyl chloride, and other degradation products of PCE. Concentrations of these contaminants are below their PRG values for most samples collected below 50 ft depth.

nam i^eamer f^are one Community Involvement Plan Page 35 September 2018 Proposed Plan for ROD S Leather Care Site May 2018 Nature and Extent of Groundwater Contamination Studies at the site show that the occurrence and movement of groundwater beneath the site is complex. Two aquifers were identified: a shallow aquifer which occurs within soil and partly to completely weathered bedrock (termed the regolith aquifer) and a deep aquifer which occurs within fractured bedrock. The weathered bedrock at the base of the regolith aquifer defines a hydrogeologic transition zone, which is a preferred pathway for groundwater flow. The depth of the transition zone varies fix)m about 29 to 75 feet below ground.

Groundwater samples were collected from monitoring wells on seven occasions between 2007 and 2016; fi’om private wells in 2007 and 2010 and fi’om the bedrock pumping well in 2007 and 2011. Groundwater samples were screened against North Carolina groundwater quality standards (NCAC 2L Groundwater Standards for Class GA groundwater) and the National primary and secondary drinking water standards (Federal maximum contaminant levels [MCLs]).

In 2016 samples were collected fi’om 32 site monitoring wells (Figure 5). The Federal MCL for PCE, 5 micrograms per liter (pg/L) was exceeded at 27 locations while the State standard (0.7 pg/L) was exceeded at 29 locations. The MCL for PCE was exceeded by a factor of 100 or more in 13 wells, including 3 wells in which the MCL was exceeded by a factor of 1,000 or more. Twenty-two of 32 locations exceeded both the MCL for TCE (5 pg/L) and the State standard for TCE (3 pg/L). The MCL for TCE was exceeded by a factor of 100 or more in 4 wells. Twenty of 25 wells exceeded the MCL and State standards (both 70 pg/L) for cis- 1,2-DCE. The MCL for cis-l,2-DCE was exceeded by a factor of 100 or more in 3 wells.

The PCE concentration in the regolith aquifer is shown on Figure 6. Sample results showed that contamination is present in wells screened throughout the water column in the regolith aquifer. The highest levels of contamination occur immediately west of the former Ram Leather building in the area of the 2008 soil removal. This area is considered to be the main contaminant source area.

Vertical profiling of groundwater conducted at four locations in 2016 identified significant vertical variations in chlorinated ethene concentrations at each location. At one of the locations, the variability appears to reflect lithologic changes with depth and illustrates the influence of clay-rich horizons on contaminant migration. The extent of PCE degradation is not consistent with depth at any of the profiled locations but instead may increase or decrease.

The present data suggest that shallow groundwater contamination extends to the top of bedrock (about 70 ft below ground) over an area that encompasses the former building and extending to ^e north, west, south, and southeast. Wells installed into the transition zone in 2015 and 2016 confirm the importance of this unit as a migration pathway. Concentrations of total chlorinated ethene compoimds in the transition zone are shown on Figure 7.

Chlorinated ethene concentrations in the bedrock aquifer have not been fully characterized and investigations are ongoing. All samples collected fi’om throughout the water column in the on-site bedrock well in 2010 exceeded the MCL and NCAC 2L standards for PCE, TCE, cis-l,2-DCE, and vinyl chloride. These contaminants were not detected in samples collected from off-site private wells in 2010, although the prior sampling of four private residences in 2007 (within 550 ft of the Site) had PCE concentrations between 5 and 100 pg/L. These private wells were screened within bedrock and were abandoned in December 2008. Sampling of private wells in 2017 (after completion of the RI Addendum Report) identified an additional residential well on Alvin Hough Road north of the site with PCE concentrations above the NCAC 2L value of 0.7 pg/L but below the MCL value of 5 pg/L.

Community Involvement Plan Page 36 September 2018 Proposed Plan for ROD Ram Leather Care Site May 2018 SCOPE AND ROLE OF THE RESPONSE ACTION The EPA is utilizing a phased approach to address contaminated media at Site. An interim remedy selected in 2004 and completed in 2008 addressed surface and subsurface soil contamination to a depth of about 18 ft below ground immediately west of the former building. A removal action in 2004 connected impacted residential properties to a municipal water line. The present effort is focused on the areas with the highest levels of contamination, which occur within the regolith aquifer. Subsequent work phases will address contamination at depth within the bedrock aquifer and off-site within the dilute plume.

The Site-wide remedial strategy is driven by the need to restore and protect the surficial regolith and deeper bedrock aquifers. The remedial strategy for the Site is; (1) aggressive remediation of source areas (e.g., soil and groundwater with high concentrations of contaminants or NAPL) and (2) phased active remediation of groundwater. This is a commonly applied approach to sites with a significant mass of contamination in a source area with off-site contaminant transport and low receptor risk concerns. Remediation will be optimized by targeting the highest levels of mass first.

Soil and groundwater contamination requiring remediation at the Site was classified into four contaminated media zones (CMZs). A CMZ represents a portion of the Site contamination which has a particular characteristic that defines the optimal remediation approach, such as lithology, contaminants of concern, depth, areal extent, and/or presence of NAPL. The CMZs, which are shown on Figure 8, are the;

• Unsaturated Zone (UZ), • Main Source Area (MSA), • Secondary Source Zone (SSZ), and • Dilute Plume (DP).

Urusaturated Zone (UZ) The UZ encompasses significantly contaminated surface and subsurface soils that occur above the water table from the ground surface to approximately 20 ft below ground. The UZ includes almost the entire footprint of the Ram Leather Care building plus the septic tank area on the north side of the building; the most intense contamination occurs on the west side of the building footprint in the vicinity of the former drum storage area.

Main Source Area (MSA) The MSA represents an approximately 40 ft thick zone of saturated soil and groundwater within the saprolite and transition zone (between approximately 20 and 60 ft below ground). It is overlain by a portion of the UZ in the vicinity of the former drum storage area and extends from the base of the UZ downward to the top of competent bedrock. The MSA zone encompasses the area identified as the primary contaminant source on the west side of the former building where the most severe groundwater contamination and the highest concentrations of adsorbed chlorinated ethenes or residual Dense Nonaqueous Phase Liquid (DNAPL) occur. This source material is thought to contribute to dissolved contamination.

The MSA is impacted with chlorinated ethene compounds in groundwater, and includes significantly contaminated soils with presumptive evidence of DNAPL and total chlorinated ethene concentrations greater than 100,000 pg/L. The highest chlorinated ethene concentration measured in soil in this zone, greater than 630,000 ng/kg, is indicative of DNAPL-impacted soils.

Secondary Source Area (SSA) The SSA surrounds the MSA and extends downgradient of the former building to the southeast. In the area

Community Involvement Plan Page 37 September 2018 Proposed Plan for ROD 7 Ran Leather Care Site May 2018 of the former building, the SSAis overlain by the UZ. The SSA encompasses depths beginning at about 10 ft below ground in unsaturated soil to about 69 ft below ground or to the top of bedrock which becomes shallower to the southeast. As with UZ, the source of this contamination is located on the west side of the building and within the drum storage area.

Total chlorinated ethene concentrations in groundwater exceed 1,000 pg/L within the SSA. In general, while chlorinated ethene concentrations were limited in the soils collected from this zone, given the dissolved phase groundwater contamination, residual DNAPL is potentially present in this zone.

Dilute Plume (DP) The DP encompasses the wider band of dissolved contamination in the saprolite and transition zones adjacent to the SSA. This zone represents chlorinated ethene concentrations in groundwater between 1 and 1,000 pg/L in the regolith aquifer and transition zone. The lithology encompassed by this zone includes saprolite and partially weathered bedrock. Additional characterization of the nature and extent of contamination in the DP is ongoing.

The NCP establishes an expectation that the EPA will address the principal threats posed by a site by treatment whenever practicable. Identifying principal threat wastes combines concepts of both hazard and risk. In general, principal threat wastes are those source materials considered to be highly toxic or mobile, which generally cannot be reliably contained in a reliable manner or would present a significant risk to human health or the environment should exposure occur. Principal threat wastes identified at the Site consist of: (1) chlorinated-ethene-contaminated soil on- and off-facihty and (2) NAPL-impacted subsurface soils in the MSA zone.

The interim remedial action to be completed under this Proposed Plan will address contamination in the UZ, MSA, and SSA zones. Contamination in the DP and in the fractured bedrock aquifer, which will continue to be assessed and evaluated, will be addressed in future remedial actions. Sampling of private drinking water wells around the site in 2017 identified a well containing low concentrations of Site-related contaminants; this interim remedial action will provide municipal water to the affected residence as a precaution.

SUMMARY OF SITE RISKS

As part of the 2016 RI addendum, the baseline human health risk assessment (HHRA) was updated to include the samples results collected during the most recent remedial investigation. The risk assessment evaluated risks to human populations that may be exposed to chemicals of concern (COCs) present in surface soil, subsurface soil, groundwater, smface water, and sediment at the Site under current and potential future conditions. The risk assessment provides the basis for determining if remedial action is warranted and if so, it identifies the contaminants and exposure pathways that must be addressed by the remedial alternatives.

Human Health Risk Assessment (HHRA) Addendum The Baseline HHRA Addendum, included as part of the RI Report, provides the basis for determining whether or not remedial action is necessary at the Ram Leather Care Site and provides the justification for performing a cleanup. The HHRA evaluated potential risks to human health due to releases of chemicals and exposure to contaminants at the Site and evaluated contaminant cleanup levels to ensure they are protective of human health and the environment.

The HHRA Addendum used a four-step process to assess site-related cancer risks and noncancer health hazards including Hazard Identification, Exposure Assessment, Toxicity Assessment, and Risk Characterization.

Although used for industrial/commercial purposes in the past, there is no current industrial activity at the Site.

Community Involvement Plan Page 38 September 2018 Proposed Plan for ROD 8 Rm Leather Care Site May 2018 Consequently, the only current use is by trespasser/visitors. In the future, the Ram Leather Care Site could be used for either residential or industrial/commercial purposes as well as by future trespassers, future construction workers and future utility workers. The HHRA Addendum evaluated the following potentially complete exposure pathways and populations:

• Incidental ingestion, dermal contact, and inhalation of fugitive dusts in subsurface soil (Construction Workers); • Inhalation of outdoor vapors from subsurface soil (Residents, Trespassers, Industrial/Commercial Workers, and Construction Workers); • Incidental ingestion and dermal contact with surface water (Residents, Trespassers, Industrial/Commercial Workers, and Construction Workers); • Ingestion of groundwater, dermal contact with groundwater, and inhalation of VOCs released from groundwater during household water use (Residents); • Ingestion of groundwater only (Industrial/Commercial Workers, and Construction Workers); • Inhalation of indoor vapors from subsurface vapor intrusion (Residents and Industrial/Commercial Workers).

An unacceptable cancer risk is identified when the Site-related cumulative cancer risk is above EPA’s risk management limit of 1 x 10'“' (1 in 10,000). A non-cancer risk is identified when the Site-related cumulative hazard quotient results in a Hazard Index (HI) greater than 1. Table 1 summarizes the cumulative cancer and non-cancer risks associated with contamination at the site.

The HHRA Addendum used default exposure assumptions and professional judgment to select exposure areas and exposure assumptions for the various receptors. These exposure assumptions are conservative and are likely to overestimate hazards and risks. The HHRA Addendum concluded:

• On Property: There are no unacceptable cancer risks or non-cancer hazards associated with exposure to surface soil. Cancer risks are within the acceptable range and non-cancer His are below the threshold for all receptors exposed to subsurface soil. There are no chemicals of concern (COC) for surface soil or subsurface soil. • On Property Future Resident Scenario: Cancer risks and non-cancer His are unacceptable for exposures to groundwater and indoor air. COCs for groundwater include benzene, bromodichloromethane, chloroform, l,l-dichloroethene, cis-l,2-DCE, trans-l,2-DCE, PCE, TCE, and vinyl chloride. COCs for indoor air include benzene, bromodichloromethane, 1,1-dichloroethene, PCE, TCE, and vinyl chloride. • On Property Current/Future Trespasser/Visitor Scenario: cancer risks are within the acceptable range and non-cancer His are below the threshold for all contaminated media. • On Property Future Industrial/Commercial Worker Scenario: cancer risks and non-cancer His are unacceptable due to exposure to groundwater and indoor air. COCs for groundwater include cis-1,2- DCE, PCE, TCE, and vinyl chloride. COCs for indoor air include PCE, TCE, and vinyl chloride. • On Property Future Construction Worker: cancer risks are within the acceptable range; however, non­ cancer His are unacceptable due to exposure to groundwater. COCs in groundwater include cis-1,2- DCE, PCE, TCE and vinyl chloride. • Off Property Resident Scenario: When evaluated without vapor intrusion, cancer risks and non-cancer His are within the acceptable range for residents exposed to off property groundwater. When evaluated with the vapor intrusion pathway, cancer risks are acceptable; however, non-cancer His are unacceptable for residents due to hypothetical use of the groundwater as a drinking water source, resulting in drinking and bathing with the water as well as breathing air that contains contaminants that have volatilized into the breathing zone in the house from the subsurface. COCs for the off property residential scenario include PCE in groundwater and indoor air.

Community Involvement Plan Page 39 September 2018 Proposed Plan for ROD 9 Rm Leather Care Site May 2018 • Off Property Industrial/Commercial Workers and Construction Workers: cancer risks are within the acceptable range and non-cancer His are below the threshold for exposures to groundwater or indoor air from off property monitoring wells. There are no COCs for these receptors exposed to off property groundwater or indoor air. • Off Property: cancer risks are within the acceptable range and non-cancer His are below the threshold for all receptors exposed to surface water. Consequently, there are no COCs for surface water.

It is the lead agency’s current judgment that the Preferred Alternative identified in this Proposed Plan, or one of the other active measures considered in the Proposed Plan, is necessary to protect public health or welfare or the environment from actual or threatened releases of hazardous substances into the environment.

Chemicals of Concern and Cleanup Levels The COCs determined by the baseline HHRA were identified in accordance with EPA guidance. COCs are chemicals that significantly contribute to an exposure pathway that either exceeds a 1 x 10^ cumulative site cancer risk or exceeds a non-cancer HI of 1. Table 2 lists the COCs in the groundwater and their associated cleanup levels for the Site. Table 3 lists the COCs for the indoor air and their associated cleanup levels for the Site.

The HHRA did not identify any COCs in surface or subsurface soil (0 to 20 ft below ground) as a consequence of direct contact. Principally, this is a result of soil excavation and contaminant removal during the prior excavation in 2008. Although not defined as a specific cleanup level, the leachability of COCs from subsurface soil is implicit as a means to achieve ground water cleanup levels.

REMEDIAL ACTION OBJECTIVES

Remedial action objectives (RAOs) describe what the proposed cleanup of die Ram Leather Care Site is expected to accomplish. The site-specific RAOs are:

• E^revent human (onsite future residents, future industrial/commercial workers, and future construction workers) exposure to site-related contaminated groundwater at concentrations above Federal MCLs or North Carolina groundwater standard regulatory levels; • Prevent human (onsite future residents and future industrial/commercial workers) exposure to site- related contaminant indoor air concentrations above HHRA cancer risk levels or HHRA non-cancer hazard levels; • Reduce or eliminate the long-term leachability of soil COCs into the groundwater or volatilization into indoor air by meeting soil leachability and vapor intrusion goals for subsurface soils; • Protect down-gradient groundwater resources by preventing expansion of the contaminated groundwater plume within the regolith aquifer; • Restore groundwater to its expected beneficial use as a drinking water supply with contaminant concentrations below MCLs.

REMEDIAL ALTERNATIVES

The Feasibility Study (FS) report evaluated media-specific remedial technologies capable of addressing impacted media in each CMZ. The remedial alternatives were screened and analyzed for their effectiveness in protecting human health and the environment, compliance with ARARs, implementability, cost, and time required to achieve RAOs and cleanup levels. The following sections summarize the alternatives that were evaluated for remediating the CMZs and the residential well.

Community Involvement Plan Page 40 September 2018 Proposed Plan for ROD 10 Rm Leather Care Site May 2018 Unsaturated Zone (UZ) The UZ contains chlorinated ethene compounds at concentrations above cleanup levels for (1) protection of underlying groundwater from soil leachate; and (2) protection for vapor intrusion. Remediation of this zone is thus focused on protecting humans from continued migration and dissolution of dense nonaqueous phase liquid (DNAPL) into groimdwater.

Four remediation alternatives were developed and evaluated for the contaminated soils in the UZ.

UNSATURATED ZONE REMEDIATION ALTERNATIVES UZ ALTERNATIVE DESCRIPTION The No Action alternative is required for consideration by the National Contingency Plan 1 No Action (NCP). No active cleanup activities will be initiated. Periodic monitoring of existing wells and reporting will be completed every five years to confirm Site conditions. Soil vapor extraction applies a vacuum to unsaturated soil to induce a controlled flow of air through the formation. Air flow removes volatile and some semi-volatile contaminants 2 Soil Vapor Extraction from the soil and passes them through an ex situ treatment system before discharging cleaned air to theatmosnhere. 3 Similar to UZ #2, this alternative would additionally excavate contaminated soil from the center of the UZ and dispose of the excavated soil at an EPA-approved off-site disposal Limited Soil Excavation with Soil facility. A vacuum would be applied to the remaining unsaturated soil to induce a V^or Extraction controlled flow of air through the formation. Air flow removes volatile and some semi­ volatile contaminants fi'om the soil and passes them through an ex situ treatment system before discharging cleaned air to the atmosphere. Similar 4 to UZ #2, this alternative would additionally mix a chemical oxidant into shallow soil in the most contaminated portion of the UZ. Following the in situ mixing, a vacuum In Situ Chemical Oxidation with would be applied to the remaining unsatiunted soil to induce a controlled flow of air Shallow Soil Mixing and Soil Vapor Extraction through the formation. Air flow removes volatile and some semi-volatile contaminants from the soil and passes them through an ex situ treatment system before discharging cleaned air to theatmosphere.

Alternative UZ #1: No Action - This alternative would not expend funds to control, isolate, or remediate contaminated soil or groundwater, and the Site would remain in its present condition. This alternative, required by the NCP and CERCLA, is a baseline alternative against which to compare the effectiveness of the other alternatives. The operation and maintenance (O&M) costs are for periodic groundwater monitoring and reporting every five years to confirm Site conditions.

Alternative UZ #2: Soil Vapor Extraction (SVE) - This alternative would install vapor extraction wells in the area where chlorinated ethene-contaminated soil was identified at shallow depths above the water table. Fifty- three (53), 4-inch diameter SVE wells screened from 5 to 20 ft below ground would be installed. A contingency has been included for thirty (30), 2-inch diameter air entry wells screened from 5 to 20 ft depth to facilitate more uniform subsurface airflow.

Air flowing through the subsurface would carry chlorinated ethenes to the surface where they would be removed from the air stream prior to discharging cleaned air to the atmosphere. These wells would treat approximately 34,920 cubic yards (cy) of contaminated soil. SVE wells beneath the former building footprint would be installed either vertically through the building slab or via angled drilling along the periphery of the slab. Equipment includes a trailer-mounted system with extraction blower, air/fluid separation tank, and vapor phase carbon. A manifold extraction system would allow phased operation of select points simultaneously. Sequencing of SVE well operation may also be used to allow their use as air entry wells.

Alternative UZ #3; Limited Soil Excavation with SVE - This alternative involves excavating soil in the center of the UZ to remove a total of approximately 12,045 cy of contaminated soil while treating the remaining

Community Involvement Plan Page 41 September 2018 Proposed Plan for ROD II Rm Leather Care Site May 2018 area using soil vapor extraction as described in Alternative UZ #2. Approximately 8,370 cy of soil would be excavated to a depth of approximately 20 ft below ground with 3,675 cy excavated from sloped sidewalls to remove contaminated soil from the suspected source area. Excavated soil would be sampled for waste profiling, segregated as necessaiy, and loaded onto trucks for off-site disposal in an approved landfill. Clean fill will be used to backfill the excavation. Soil excavation is expected to remove the majority of the suspected source area and any NAPL present in the UZ.

This alternative would also include the installation of thirty-five (35), 4-inch diameter SVE wells and eleven (11) 2-inch diameter air entry contingency wells screened from 5 to 20 ft below ground as described for Alternative UZ #2.

Alternative UZ #4: In Situ Chemical Oxidation (ISCO) with Shallow Soil Mixing and Soil Vapor Extraction (SVE) - This alternative would mix a chemical oxidant (assumed to be potassium permanganate) into the top 20 feet of soil beneath the center of the UZ to destroy chlorinated ethene contaminants. Direct contact of the oxidant with soil contaminants is required to destroy the chlorinated compounds by chemical oxidation. The remaining area would be treated using soil vapor extraction as described in Alternative UZ #2.

Soils will be mixed with oxidants in 20-ft by 20-ft cells to a depth of 20 ft below ground using an ALLU or Lang tool on tracked excavators to treat approximately 11,550 cy of contaminated soil. This in situ mixing will enhance the contact with the most contaminated soil for uniform coverage throughout the UZ.

Alternative UZ #4 also would include the installation of thirty-five (35) 4-inch diameter SVE wells and eleven (11), 2-inch diameter air entry contingency wells screened from 5 to 20 ft bgs as described for Alternative UZ #2.

Main Source Area (MSA) Remediation of the MSA zone will protect humans from exposure to contaminants that continue to dissolve into groundwater from chlorinated ethenes that are adsorbed to soil or that migrate to groundwater as residual DNAPL. The remedial strategy for the MSA is to reduce the mass of COCs present in the zone or to contain the contaminants in a manner that prevents groundwater concentrations from exceeding their cleanup values. Potential remedial options are governed by the depth of the zone and its location, in part, beneath the concrete foundation of a portion of the former building footprint, the properties of the COCs, and the low permeability of the formations comprising the MSA.

Four remediation alternatives were developed and evaluated for the contaminated soils and groundwater in the MSA.

MAIN SOURCE AREA REMEDIATION ALTERNATIVES MSA ALTERNATIVE DESCRIPTION This alternative is required for consideration by the NCP. No active cleanup activities will 1 No Action be initiated. Periodic monitoring of existing wells and reporting will be completed every five years to confirm Site conditions. 1 In Situ Chemical Oxidation with Deep soil mixing of an ISCO agent (assumed to be potassium permanganate) using LDA Large Diameter Augers (LDA) technology.

Injection of amendments such as a carbon substrate with zero-valent iron or soluble ferrous In Situ Bioremediation with 5 iron, bioaugmentation, and pH adjustment to reduce residual DNAPL, chlorinated ethenes Chemical Reduction (EISB/ISCR) adsorbed on saturated soil, and chlorinated ethenes dissolved in groundwater.

In Situ Thermal Treatment Thermalconductionheating(or equivalent) of the MSA to approximately 100°C.

Community Involvement Plan Page 42 September 2018 Proposed Plan for ROD Ram Leather Care Site May 2018

Alternative MSA #1: No Action - This alternative would not expend funds to control, isolate, or remediate contaminated soil or groundwater, and the Site would remain in its present condition. This alternative, required by the NCP and CERCLA, is a baseline alternative against which the effectiveness of the other alternatives can be compared. The O&M costs are for periodic groundwater monitoring and reporting every five years to confirm Site conditions.

Alternative MSA #2: In Situ Chemical Oxidation (ISCO) with Large Diameter Augers (LDA) - This alternative would mix an ISCO agent (assumed to be potassium permanganate) into subsurface soil and saprolite fix)m 20 to 50 ft depth using large diameter auger (LDA) technology. The ISCO agent will destroy chlorinated ethene compounds through chemical oxidation. Direct contact of the ISCO agent with the contaminant is required for this process. In situ mixing by LDA will enhance the contact of the oxidant with the most contaminated soil for uniform coverage throughout the MSA.

Soils would be mixed with oxidants using an 8-ft diameter auger at 142 injection locations. Potassium permanganate would be batch mixed into a slurry with hydrant water or recovered groundwater, stored in a polyethylene feed tank, applied to the augers at each injection location, and then thoroughly mixed into the soil ming ports on the augers. Excess oxidant would be added at the base of the saprolite (~40-ft below ground) to allow pooled oxidant to flood into the underlying transition zone as driven by density for an anticipated additional treatment depth of 10 ft.

This alternative will result in a slight increase in ground elevation due to die soils being l^s consolidated following auger mixing.

Alternative MSA #3; Enhanced In Situ Bioremediation with Chemical Reduction (EISB/ISCR) - This alternative would inject amendments into the subsurface to destroy chlorinated ethene compounds through chemical reduction. Treatment by chemical reduction would occur through direct contact or by bacterial action that breaks down PCE and its degradation products.

Potential amendments include a carbon substrate with zero-valent iron (ZVI) or soluble ferrous iron, bioaugmentation (addition of bacterial cultures), and pH adjustment. These would reduce residual DNAPL, chlorinated ethenes adsorbed on saturated soil, and chlorinated ethene compounds dissolved in groundwater. Amendments would be added via a dense grouping of forty-four (44), 2-inch diameter injection wells that would dispense amendments fix)m 20 to 50 ft bgs in the saprolite and thirteen (13), 4-inch diameter injection wells dispensing amendments from 50 to 60 ft bgs in the transition zone of the MSA.

Alternative MSA #4: In Situ Thermal Treatment - This alternative would raise the temperature of die MSA zone to approximately 100 °C through thermal conduction heating (or equivalent). Increasing the ten^erature of the subsurface would allow chlorinated ethenes to be more easily mobilized and extracted, or degraded in place through one of several processes.

Community Involvement Plan Page 43 September 2018 Proposed Plan for ROD Ram Leather Care Site May 2018

Treatment of the entire MSA area (9,000 square feet [sq ft]) would be accomplished by installation of seventeen (17) heater vacuum wells screened fixim 10 ft to the top of bedrock at approximately 60 ft Additionally, seventy (70) heater-only wells would be installed to the top of the bedrock and seven (7) thermocouple wells would be installed to monitor the subsurface temperature. Contaminated fluids extracted from the wells will be passed through a heat exchanger, NAPL separator, tray air stripper, and granular activated carbon to remove contaminants. Treated water would then be injected into an onsite deep well for disposal. Extracted vapors would be passed through a heat exchanger and activated carbon vapor phase treatment; treated air would be released to the atmosphere. A portion of the concrete foundation of the original building footprint and the existing building will need to be demolished.

Secondary Source Area (SSA)

Four remediation alternatives were developed and evaluated for die contaminated saturated soil and groundwater in the SSA.

SECONDARY SOURCE AREA (SSA) REMEDIATION ALTERNATIVES SSA ALTERNATIVE DESCRIPTION This alternative is required for consideration by the NCP. No active cleanup activities will 1 No Action be initiated. Periodic monitoring of existing wells and reporting will be completed every five years to confirm Site conditions.

This alternative uses ISCO permeable reactive barriers and a central groundwater recovery 2 In Situ Chemical Oxidation (ISCO) zone to draw contaminated groundwater through the barrier/treatment.

Enhanced In Situ Bioremediation This alternative involves injection of amendments such as a zero valiant iron (ZVI) in three ) with Chemical Reduction (EISB/ISCR) transects of wells across the SSA.

1 In Situ Thermal Treatment and This alternative includes thramal conduction heating (or equivalent) of the SSA to Biobarrier approximately 100®C.

Alternative SSA #1: No Action - This alternative would not expend funds to control, isolate, or remediate contaminated soil or groundwater, and the Site would remain in its present condition. This alternative, required by the NCP and CERCLA, is a baseline alternative against which the effectiveness of the other alternatives can be compared. The O&M costs are for periodic groundwater monitoring and reporting every five years to confirm Site conditions.

Community Involvement Plan Page 44 September 2018 Proposed Plan for ROD 14 Rm Leather Care Site May 2018 Alternative SSA #2: In Situ Chemical Oxidation (ISCO) - This alternative would inject ISCO reagents into the subsurface to form permeable reactive barriers. A central groundwater recovery zone would draw contaminated groundwater through the barriers for treatment. Oxidant from the treatment barriers also would be expected to drift downgradient where it would have a direct effect on contaminated soils. Injection of oxidants such as potassium permanganate or persulfate would destroy residual DNAPL and chlorinated ethenes that are adsorbed on saturated soil in the barriers themselves and would also destroy contaminants dissolved in groundwater as the water passes through the barriers.

The oxidant barriers would be created by a line of forty-five (45) injection wells that almost completely encircle the MSA zone and the former building fooQ)rint and another eleven (11) injection wells installed in a line downgradient to the southeast. The downgradient barrier would treat groundwater that is drawn into this treatment zone. Potassium permanganate (the ISCO reagent) would be batch mixed into a slurry with hydrant water or recovered groundwater, stored in a polyethylene feed tank, applied to the saprolite and transition zone in each injection location using a manifold system.

Twenty-eight (28) wells would be installed inside the oxidant barrier and used to extract groundwater. These wells encircle the MSA plus extend out by one well to the southwest and by three wells to the northeast of the MSA to provide additional capture. All of these wells would be dual-screened from approximately 20 ft below ground (top of water table) to approximately 45 to 65 ft below ground in saprolite (3 ft fix)m the top of the transition zone) and across the bottom 5 ft of the transition zone. An injection packer would be used to isolate saprolite from the transition zone during injection and recovery. The ISCO injection wells would have a radius of influence of 8 ft with no overlap. Extracted groimdwater would be treated with an air stripper prior to injection via a deep well(s). The remedy also includes the installation of 6 performance monitoring wells.

Alternative SSA #3: Enhanced In Situ Bioremediation with Chemical Reduction (EISB/ISCR) - This alternative would inject chemical amendments into the subsurface to destroy contaminants by chemical reduction. This treatment would reduce residual DNAPL, chlorinated ethenes adsorbed on saturated soil, and chlorinated ethenes dissolved in groundwater. It offers the benefit of both anaerobic biodegradation and chemical reduction treatment mechanisms.

Amendments such as a carbon substrate with zero valent iron, bioaugmentation, and pH adjustment, would be added via four transects of injection/recirculation wells that alternate with three transects of extraction wells. The four transects of injection/recirculation wells would contain a total of forty (40) 2-inch diameter wells screened in the saprolite to the top of the transition zone. Eleven injection/recirculation wells comprise a biobanier transect downgradient of the other injection wells. The injection wells would have an estimated radius of influence of 8 ft. Emulsified oil carbon substrate with zero valent iron would be batch mixed into a slurry with hydrant water or recovered groundwater, stored in a polyethylene feed tank, applied to the saprolite and transition zone in each injection location using a manifold system.

The three transects of extraction wells would contain a total of twenty-eight (28), 4-inch diameter wells for the extraction of groundwater. All of these wells would be dual-screened from approximately 20 ft (top of water table) to approximately 45 to 65 ft below ground in saprolite (3 ft from the top of the transition zone) and across the bottom 5 ft of the transition zone. An injection packer would be used to isolate saprolite from the transition zone during injection and recovery. Recirculated water would be treated with carbon adsorption to remove contaminants, pH adjustment and an oxygen scavenger prior to reinjection.

Contaminants within the SSA outside the immediate treatment zone would be addressed through transport towards the remediation area and monitored natural attenuation.

Community Involvement Plan Page 45 September 2018 Proposed Plan for ROD 15 Rm Leather Care Site May 2018 Alternative SSA #4: In Situ Thermal Treatment and Biobarrier - This alternative would be similar to Alternative MSA #4 but would additionally include an EISB biobarrier wall similar to that in Alternative SSA #3. As in Alternative MSA #4, thermal conductive heating (or equivalent) would be used to heat the subsurface to approximately 100 °C. Increasing the temperature of the subsurface would allow chlorinated ethenes to be more easily mobilized and extracted, or degraded in place through one of several processes. The biobarrier would use chemical reduction to treat water migrating downgradient to the southeast from the site. Alternative SSA #4 would require demolition of a portion of the concrete building slab and the existing building.

A total volume of 81,850 cy would be treated using 82 heater-vacuum wells screened from 10 ft to the top of the bedrock at approximately 65 ft below ground. Approximately 278 heater-only wells also would be installed to the top of the bedrock. Contaminated groundwater extracted ^m the subsurface would be passed through a heat exchanger, NAPL separator, tray air stripper, and granular activated carbon to remove contaminants prior to injecting the water into a deep well for disposal on site. Vapors extracted from the subsmface would be passed through a heat exchanger and activated carbon for treatment.

Ten (10) EISB injection wells would be installed to create a biobarrier in the saprolite to address downgradient contaminant migration. This barrier would be installed across the SSA in a line southeast of the building and would be formed by injecting amendments into the subsurface. The amendments would consist of an emulsified oil carbon substrate plus bioaugmentation and pH adjustment that would be batch mixed into a slurry with hydrant water or recovered groundwater, stored in a polyethylene feed tank, applied to the saprolite and transition zone in each injection location using a manifold system. The injection wells would be dual-screened from approximately 20 ft bgs (top of water table) to approximately 45 to 60 ft bgs in saprolite (3 ft from the top of the transition zone) and across the bottom 5 ft of the transition zone. An injection packer would be used to isolate saprolite from the transition zone during injection and recovery. The injection wells would have an estimated radius of influence of 8 ft.

Contaminants in saprolite outside of the treatment zone would be addressed through transport towards die remediation area and MNA.

Residential Water (RW) The residential water zone includes a residence on Alvin Hough Road north of the site where sampling of well water indicated the presence of site-related contaminants in a private well presumably screened in the bedrock aquifer.

The Feasibility Study report evaluated two remedial alternatives including No Action and Municipal Water Line Extension. Three potential routes for the water line extension were evaluated. Under Option 1, the water line would be extended from the east side of the Norfolk Southern rail line north along the rail grade to Alvin Hough Road, then east along the road. Under Option 2, the water line would be extended from a property serviced by municipal water east of the site through private property to Alvin Hough Road. Option 3 would extend the water line from the west side of Albemarle Road east along Alvin Hough Road.

EVALUATION OF ALTERNATIVES

The remedial alternatives for the CMZs were evaluated using the nine criteria specified in the NCP, which include two threshold criteria, five balancing criteria and two modifying criteria in order to select the preferred interim cleanup plan for the Site. The nine criteria are shown in the table below entitled. Evaluation Criteria for Superfund Remedial Altermatives.

Community Involvement Plan Page 46 September 2018 Proposed Plan for ROD Ram Leather Care Site May 2018

EVALUATION CRITERIA FOR SUPERFUND REMEDIAL ALTERNATIVES THRESHOLD CRITERIA

Overall Protectiveness of Human Health and the Environment detennines whether an alternative eliminates, reduces, or controls threats to public health and the environment through institutional controls, engineering controls, or treatment. Compliance with Applicable or Relevant and Appropriate Requirements (ARARs) evaluates whether the alternative meets Federal and State environmental statutes, regulations, and other requirements that pertain to the site, or whether a waiver is justified. EVALUATION Criteria Long-term Effectiveness and Permanence considers the ability of an alternative to maintain protection of human health and the environment over time. Reduction of Toxicity, Mobility, or Volume of Contaminants through Treatment evaluates an alternative's use of treatment to reduce the harmful effects of principal contaminants, their ability to move in the environment, and the amount of contamination present. Short-term Effectiveness considers the length of time needed to implement an alternative and the risks the alternative poses to workers, residents, and the environment during implementation. Implementability considers the technical and administrative feasibility of implementing the alternative, including factors such as the relative availability of goods and services. Cost includes estimated capital and annual operations and maintenance costs, as well as present worth cost. Present worth cost is the total cost of an alternative over time in terms of today's dollar value. Cost estimates are expected to be accurate within a rangeof +50 to -30 percent.

Modifying Criteria State/Support Agency Acceptance considers whether the State agrees with the EPA’s analyses and recommendations, as described in the RI/FS and Proposed Plan. Community Acceptance considers whether the local community agrees with EPA's analyses and preferred alternative. Comments received on this Proposed Plan are an important indicator of community acceptance.

A detailed analysis of the remedial alternatives was presented in the 2018 Feasibility Study report. This analysis compared each remedial alternative for each CMZ to the Threshold and Evaluation Criteria highlighted in the table above. The analysis was conducted by individually evaluating the CERCLA Feasibility Study guidance sub-criteria for the Threshold and Evaluation Criteria. Each group of sub-criteria was individually evaluated and given a subjective rating and score against the context of the Site Remedial Action Objectives. Scores for the primary Threshold and Evaluation Criteria were developed by averaging sub-criteria scores. Cost was not assigned a score, but the relative cost between remedial alternatives was considered in the comparison. The scores were developed for the threshold and/or primary balancing criteria with “5” being the highest score and “1” being the lowest score. The scores were summed to provide a total (out of 30 points) for each alternative. The tables below summarize the primary criterion scores from this analysis for each CMZ; scores were not developed for the residential water alternatives which differ only in the route the constructed water line would follow.

Community Involvement Plan Page 47 September 2018 Proposed Plan for ROD Ram Leather Care Site May 2018 Unsaturated Zone (UZ)

SUMMARY OF DETAILED ANALYSIS FOR ALTERNATIVES FOR THE UNSATURATED ZONE

g in 1 Mobility, Score

Volume

1 & Long-Tenn Short-Tenn Total Reduction Effectiveness Effectiveness 1O Toxicity, I UZ ALTERNATIVE P 1 No Action 1.00 1.00 1.00 1.00 4.00 4.50 12.50 2 Soil Vapor Extraction 4.00 3.75 4.00 3.70 3.75 4.43 23.63 3 Limited Soil Excavation with Soil Vapor Extraction 4.50 3.67 4.25 3.90 3.63 4.38 24.33 4 In Situ Chemical Oxidation with Shallow Soil Mixing and Soil 4.50 4.00 4.25 4.30 3.75 4.21 25.01 Vapor Extraction

Main Source Area (MSA)

SUMMARY OF DETAILED ANALYSIS FOR ALTERNATIVES FOR THE MAIN SOURCE AREA

!, in

Score

Mobility, Protecticm

Volume

& ! Total Short-Term Long-Term Reduction Effectiveness Effectiveness Impiementability Overall Toxicity,

MSA ALTERNATIVE 1 No Action 1.00 1.00 1.00 1.00 4.00 4.50 12.50 2 In Situ Chemical Oxidation with Large Diamet^ Augers (LDA) 4.50 4.25 4.00 4.30 3.88 3.93 24.86 3 In Situ Bioremediation with Chemical Reduction (EISB/ISCR) 4.00 3.75 3.67 4.00 3.88 3.93 23.23 4 In Situ Thermal Treatment 4.50 4.25 4.00 4.50 3.88 4.14 25.27

Secondary Source Area (SSA)

SUMMARY OF DETAILED ANALYSIS FOR ALTERNATIVES FOR THE SECONDARY SOURCE AREA

in with

Score

Mobility, Protection

ARARs Volume

& Long-Term Short-Term Total Reduction Effectiveness Efiectiveness Impiementability Overall Compliance Toxicity,

SSA ALTERNATIVE 1 No Action 1.00 1.00 1.00 1.00 4.00 4.50 12.50 2 In Situ Chemical Oxidation (ISCO) 3.50 3.75 3.83 3.80 3.75 4.00 22.63 3 Enhanced In Situ Bioremediation with Chemical Reduction 3.50 3.75 3.67 3.80 4.00 3.86 22.58 (EISB/ISCR) 4 In Situ Thermal Treatment and Biobarrier 4.50 4.25 4.17 4.50 4.00 4.29 25.71

Community Involvement Plan Page 48 September 2018 Proposed Plan for ROD Ram Leather Care Site May 2018

OVERALL PROTECTIVENESS OF HUMAN HEALTH AND THE ENVIRONMENT (HH&E)

Because the No Action alternatives would not be protection of human health and the environment, the No Action alternatives were not carried over for further analysis.

Unsaturated Zone - All of the UZ action alternatives would be protective of human health and the environment. Alternatives UZ #3 (Limited Soil Excavation with Soil Vapor Extraction) and UZ #4 {In Situ Chemical Oxidation with Shallow Soil Mixing and Soil Vapor Extraction) both offer complete destruction or removal of COCs. However, excavation of the contamination is a more assured technology as the success of any in situ chemical oxidation application depends on contact and thorough mixing of the soils with the oxidant. Alternative UZ #2, Soil Vapor Extraction, also provides strong overall protection of HH&E.

Main Source Area - All of the MSA action alternatives would be protective of human health and the environment. Alternative MSA #4 {In Situ Thermal Treatment) affords a robust, fast, and complete destruction of chlorinated ethenes. Alternative MSA #2 {In Situ Chemical Oxidation with Large Diameter Augers) also delivers an aggressive approach with a high chance of success in a short timeframe. Enhanced In Situ Bioremediation with Chemical Reduction (MSA #3) is expected to be effective, but has inherent limitations with amendment distribution via direct injection and is less proficient at handling higher volumes of DNAPL.

Secondary Source Area - All of the SS A action alternatives would be protective of human health and the environment. SSA #4 {In Situ Thermal Treatment with Biobarrier) is the only alternative that can provide nearly complete protection of HH&E based upon the level of aggressiveness and full coverage of the remedy. The In Situ Chemical Oxidation and In Situ Bioremediation with Chemical Reduction remedies (SSA #2 and SSA #3, respectively) will be protective of HH&E but have inherent limitations with the contact of amendments due to the lithology. The in situ bioremediation approach (SSA #3) relies on a chemical and biological reduction process to achieve mass reduction and is, therefore, somewhat less aggressive. The in situ chemical oxidation alternative (SSA #2) is the most susceptible to geotechnical issues related to lithologic heterogeneity. Thermal enhancement (SSA #4) offers the best option for overcoming this limitation. The in situ chemical oxidation and in situ bioremediation options are projected to take longer to achieve protection, principally due to the expectation that residual hot spots will require follow-up treatment.

Residential Water - All of the RW Alternatives would be protective of human health and the environment.

COMPLIANCE WITH APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS

Remedial actions must comply with Applicable or Relevant and Appropriate Requirements (ARARs) of federal and state laws, statutes, and regulations. ARARs are determined by applying a two-tiered test to determine firet whether the requirement is applicable and second to determine whether the requirement is relevant and appropriate.

Applicable requirements are those cleanup standards, controls, and other substantive environmental protection requirements, criteria, or limitations promulgated under federal or state law that specifically address a hazardous substance, pollutant, or contaminant, remedial action, location, or other circumstance at a Superfund site. Relevant and appropriate requirements are those cleanup standards, standards of control, or other substantive environmental provisions that do not directly and fully address site conditions but address similar situations or problems to those encountered at a Superfimd site. Whether or not a requirement is appropriate (in addition to

Community Involvement Plan Page 49 September 2018 Proposed Plan for ROD 19 Rm Leather Care Site May 2018 being relevant) will vary depending on factors such as the duration of the response action, the form or concentration of the chemicals present, the nature of the release, the availability of other standards that more directly match the circumstances at the site, and other factors.

In addition, non-promulgated advisories or guidance documents issued by federal or state governments, referred to as To Be Considered (TBC), also should be identified. TBCs are not considered legally enforceable and, therefore, are not considered to be applicable for the site but are evaluated along with ARARs as part of the risk assessment to set protective cleanup levels.

There are three types of ARARs: chemical-specific, action-specific, and location-specific. Chemical-specific ARARs are usually health or risk-based restrictions on the amount or concentration of a chemical that may be found in or discharged to the environment. Action-specific ARARs establish controls or restrictions on the remedial activities which are part of the remedial solution. Action-specific ARARs are triggered by the specific activity rather than the chemicals present. Location-specific ARARs prevent damage to unique or sensitive areas, such as floodplains, historic places, wetlands, and fragile ecosystems, and restrict other activities that are potentially harmful because of where they take place. Chemical- specific, action-specific, and location-specific ARARs including TBCs for the Site have been identified and are listed in the 2016 Feasibility Study.

Compliance with ARARs is a challenging criterion to evaluate because of the number and multiple types of ARARs that can apply to a site. In general, chemical-specific ARARs (e.g., water quality standards) can be met most effectively by reducing contaminant mass fi'om a site (by treatment or by removal). In particular, the abiUty of a remedial alternative to meet the target cleanup level(s) for the contaminants of concern is important.

Unsaturated Zone - There are no chemical-specific ARARs that directly apply to the UZ; however, residual contamination could be leached from the soil and carried to the water table. As such, actions taken in the UZ could potentially affect attainment of chemical-specific ARARs in the MSA and SSA zones. Alternative UZ #4, In Situ Chemical Oxidation with Shallow Soil Mixing, is projected to be the most aggressive treatment alternative and is expected to have the most comprehensive success at reducing the mass and concentration of contaminants, and should do so in a short timefiame (less than one year). The soil excavation remedy (UZ #3) offers an incremental advantage as it provides complete removal of the contaminant mass and the shortest timeframe of all remedies. Alternative UZ #2, Soil Vapor Extraction, scored lower on chemical-specific ARARs due to it being the least robust of the active remedies at removing or destroying contaminant mass in the subsurface. Action-specific ARARs are expected to be primarily procedural and/or regulatory (e.g., dust control, cap design, emissions control, and injection control permits) and should be easily attainable.

Main Source Area - Alternatives MSA #4 (In Situ Thermal Treatment) and MSA #2 (In Situ Chemical Oxidation with Large Diameter Augers) are projected to be the most aggressive treatment alternatives and are expected to have the most comprehensive success at reducing the mass and concentration of contaminants in a short timeframe (less than one year). Alternative MSA #2 has one drawback in this respect as it depends on density-driven flow for treatment of the Transition Zone which is a significant transport pathway. Alternative MSA #3 (Enhanced In Situ Bioremediation with Chemical Reduction) can ultimately meet all chemical-specific ARARs, but is expected to do so over a longer timefi-ame and with supplemental injections required to treat hot spots of contamination. Action-specific ARARs are expected to be primarily procedural and/or regulatory (e.g., dust control, cap design, emissions control, and injection control permits) and should be easily attainable, so this ARAR category is not a substantial differentiator.

Secondary Source Area -The biggest differentiator between the remedies is the close array spacing allotted for the thermal treatment remedy and the timeframe in which compliance with the ARARs will be achieved. Alternative SSA #4 (In Situ Thermal Treatment) is expected to achieve 95 to 99% reduction in chlorinated ethene concentrations based on similar site experience and it has a treatment timeframe of 1 year. Both In Situ

Community Involvement Plan Page 50 September 2018 Proposed Plan for ROD 20 Rm Leather Care Site May 2018 Chemical Oxidation and Enhanced In Situ Bioremediation with Chemical Reduction (Alternatives SSA #2 and SSA #3, respectively) can easily attain the cleanup levels if suitable contact with the contaminants can be achieved. All of the action alternatives provide reasonable assurances of meeting the location- and action- specific ARARs.

Residential Water - Municipal water that would be supplied as part of Alternative RW #2 would meet all chemical-specific ARARs. Location- and Action-specific ARARs applicable to installation of the water line would be met during the design phase.

LONG-TERM EFFECTIVENESS AND PERMANENCE

Unsaturated Zone - This criterion has particular importance for the UZ remediation due to the RAOs to prevent human exposure to site-related contaminants and isolate or treat NAPL. Thus, aggressive and comprehensive technologies can be expected to provide better assurance of long-term effectiveness and permanence. Alternatives that physically remove contaminants fi'om the Site media provide the most protection for the longest period, which all three active remedial alternatives offer. Alternative UZ #3 (Limited Soil Excavation with Soil Vapor Extraction) would provide a guaranteed successful outcome and eliminate the NAPL component from the imsaturated source area. While it scored the same as Alternatives UZ #4 {In Situ Chemical Oxidation with Shallow Soil Mixing) and UZ #2 (Soil Vapor Extraction), the soil excavation remedy offers an incremental advantage as it provides complete removal of the contaminant mass and the shortest timeframe of all remedies. Soil Vapor Extraction (UZ #2) was ranked slightly lower than the other alternatives as it is the least robust of the active remedies at removing or destroying contaminant mass in die subsurface. The likelihood that all alternatives would meet performance specifications in the near term is high.

Main Source Area - This criterion is important for the MSA remediation due to the RAOs of preventing human exposure to site-related contaminants and treatment of NAPL as a principal threat waste. Thus, aggressive and comprehensive technologies can be expected to provide better assurance of long-term effectiveness and permanence. Alternatives that physically treat or remove contaminants finm the Site media provide the most protection for the longest period. Both Alternatives MSA #2 {In Situ Chemical Oxidation with Large Diameter Auger) and MSA #4 {In Situ Thermal Treatment) would provide a uniform treatment and eliminate the NAPL component from the source area with a high degree of confidence. These alternatives have a high mass destruction potential with a low residual risk or chance for contaminant rebound. Alternative MSA #3 (Enhanced In Situ Bioremediation with Chemical Reduction) also offers good long term effectiveness witii the emplaced zero valent iron capable of long-term treatment of any contaminants that continue to be transported to the zone by groundwater flow. However, Alternative MSA #3 was ranked lower due to potential concerns including: 1) uncertain amendment distribution; 2) dosing needed for DNAPL; and 3) increased long term operation and monitoring costs. The likelihood that all alternatives would meet performance specifications in the near term is high.

Secondary Source Area - Alternative SSA #4 {In Situ Thermal Treatment with Biobarriers) all but eliminates the risk that residual contamination will remain and it has the highest assurance of meeting the RAOs. The risk of residual contamination remaining in the subsurface following Alternatives SSA #2 {In Situ Chemical Oxidation) and SSA #3 (Enhanced In Situ Bioremediation with Chemical Reduction) is somewhat higher. Alternative SSA #4 likely will not require as many 5-Year Reviews as other alternatives and will likely require a shorter operation and maintenance period compared to other alternatives. Given the low natural oxidant demand of the subsurface, in situ chemical oxidation (Alternative SSA #2) is a good choice for long term effectiveness as the oxidant (presumed as permanganate) should persist for over two years and will be continuously added (or pulsed) to injection wells to freshen the dose. Enhanced in situ bioremediation with chemical reduction (Alternative SSA #3) should have longevity of up to 5 years after injection of the amendments. AH alternatives have inherent flexibility and reliable controls. Alternative SSA #3 was ranked

Community Involvement Plan Page 51 September 2018 Proposed Plan for ROD 21 Rm Leather Care Site May 2018 slightly lower than Alternative SSA #2 due to the potential for creating the more toxic and mobile vinyl chloride as a biological daughter product and the need to properly adjust the biogeochemistry and bacteria populations. Overall, all of the remedies evaluated (excluding the no action alternative) would achieve similar outcomes with successful long-term results.

Residential Water - Installation of a municipal water line and supply of municipal water would provide a permanent, long-term solution to protect HH&E for all consumptive uses. It would also permit other nearby residents to be provided with municipal water if their drinking water wells begin to show evidence of contamination.

REDUCTION OF TOXICITY, MOBILITY, AND VOLUME (T/MAO THROUGH TREATMENT

Unsaturated Zone - Alternative UZ #4, In Situ Chemical Oxidation with Shallow Soil Mixing and Soil Vapor Extraction, offers the best subjective choice for reduction of the mass, volume, and concentration of chlorinated ethenes in a short timeframe (less than one year). Alternative UZ #4 provides permanent reduction of T/MA^ in contrast to Alternative UZ #3 (Limited Soil Excavation with Soil Vapor Extraction) which essentially relocates the contaminants to a landfill without treatment. Soil Excavation was rated higher than Alternative UZ #2 (Soil Vapor Extraction) because it provides complete removal of the contaminant mass in the shortest timeframe of all remedies. Soil Vapor Extraction has projected reductions in T/M/V via mass removal and sorption onto carbon similar to those of Alternative UZ #4, but Alternative UZ #2 has the longest timeframe for operation (five years).

Main Source Area - Alternative MSA #4 (In Situ Thermal Treatment) is expected to have the most comprehensive success at reducing the mass, volume, and concentration of contaminants in a short timeframe (less than one year). MSA Alternative # 2 (In Situ Chemical Oxidation with Large Diameter Augers) may result in residual contamination remaining trapped in clumps of clay and the auger soil mixing technique cannot be used directly in the Transition Zone. Alternative MSA #3 (Enhanced In Situ Bioremediation with Chemical Reduction) has a marginally lower expectation for overall T/M/V reduction in the near term due to the heterogenous lithology and potentially incomplete mixing of amendments into the subsurface.

Secondary Source Area - Alternative SSA #4 (In Situ Thermal Treatment with Biobarrier) has the highest potential to reduce T/M/V. Alternatives SSA #2 (In Situ Chemical Oxidation) and SSA #3 (Enhanced In Situ Bioremediation with Chemical Reduction) are capable of complete reduction of T/M/V but have a higher uncertainty. All remedies involve a focused groundwater removal component that will help capture and contain the volume of the dissolved plume in both the Secondary Source Area and Dilute Plume media zones.

Residential Water - Installation of a municipal water line would not reduce the T/M/V of contamination. Because the private well in question would no longer be pumping, migration of contamination could potentially slow.

SHORT TERM EFFECTIVENESS

The short-term effectiveness of remedial alternatives considers how well HH&E is protected with respect to the community and potential site workers, the projected environmental impacts, and the time to achieve RAOs during implementation. The effectiveness of a remedy at ensuring short-term protection during implementation of a reme^al action depends on the procedures and safeguards used by the remediation contractor.

Unsaturated Zone -Alternative UZ #4 (In Situ Chemical Oxidation with Shallow Soil Mixing) was ranked high because it should have the smallest impact on the community and construction workers, has minimal environmental impacts and has a relatively short implementation timeframe (one year). Alternative UZ #2 (Soil

Community Involvement Plan Page 52 September 2018 Proposed Plan for ROD 22 Rm Leather Care Site May 2018 Vapor Extraction) also should also have minimal impacts, but this alternative has a longer projected timefiame. The excavation component of Alternative UZ #3 (Limited Excavation with Soil Vapor Extraction) increases die potential for short-term impacts to the community and workers, although these issues can be effectively managed

Main Source Area - The three action alternatives for the MSA have equivalent ratings for short-term effectiveness although they differ in their short term protection versus the time required to meet the remedial action objectives. Alternatives MSA #2 {In Situ Chemical Oxidation with Large Diameter Augers) and MSA #4 {In Situ Thermal Treatment) both present a higher risk to workere and the community during construction of the remedy and they have higher potential environmental impacts. Although Alternative MSA #3 (Enhanced In Situ Bioremediation with Chemical Reduction) is expected to have the smallest impact on the community and construction workers, it has a markedly longer projected timeframe to achieve the remedial action objectives.

Secondary Source Area - There was little differentiation in the scores among the various action alternatives for the SSA for short-term effectiveness. Alternatives SSA #3 (Enhanced In Situ Bioremediation with Chemical Reduction) and SSA #4 {In Situ Thermal Treatment with Biobarriere), have equal rankings. Alternative SSA #3 would be the least disruptive and pose the lowest risk to the community and workers during implementation. Alternative SSA #4 would be quickest to achieve remedial action objectives. Alternative SSA #2 {In Situ Chemical Oxidation) was ranked slightly lower due to the longer timeframe to meet remedial action objectives and the potential, yet manageable, risk for a release of oxidant reagents to impact local surface water.

Residential Water - Installation of the water line under all options will have short-term in^acts to traffic on Alvin Hough Road. If construction option 1 is selected, construction will additionally affect the railroad right- of-way and private property. Construction option 2 would significantly affect private property. Option 3 would additionally affect traffic on Albemarle Road and require permission fixim Norfolk Southern to install the water line benea& their tracks.

IMPLEMENTABILITY

Implementing remedial alternatives involves design, planning, construction or installation, and operational components of remedial actions. The overall reliability and operational flexibility is also considered in this criterion. The efficiency with which an alternative can be installed and operated impacts how well an alternative achieves its level of protection (the first threshold criterion) and attains ARARs (the second threshold criterion). In some cases, implementation of the alternative could be technically difficult or impossible given site-specific limitations. In all CMZs, the No Action alternative would be the simplest to implement.

Unsaturated Zone - All three action alternatives are considered to have good implementability. Alternative UZ #2 (Soil Vapor Extraction) was scored the second highest because it will be easier to monitor for remedial effectiveness and make remedial modifications with minor site disruption. However, this alternative has the longest implementation timefi^ame (estimated at 5 years). Alternative UZ #3 (Limited Excavation with Soil Vapor Extraction) and UZ #4 {In Situ Chemical Oxidation with Shallow Soil Mixing) would be relatively simple to construct and implement with removal of the onsite building but would require an extensive earthmoving effort and real-time monitoring.

Main Source Area - All three action alternatives are considered to have good implementability. Alternative MSA #4 {In Situ Thermal Treatment) is a well proven remedy that centers on well drilling and deployment of existing integrated equipment fi’om the thermal remediation vendor. In Situ Chemical Oxidation with Large Diameter Augers (Alternative MSA #2) also is proven and uses prevailing vendor equipment; however the large diameter augers cannot penetrate the more competent rock in the Transition Zone and may be affected by

Community Involvement Plan Page 53 September 2018 Proposed Plan for ROD 23 Rm Leather Care Site May 2018 residual bouldere and rocks that may be present in the saprolite and clumping of clays that would inhibit thorough mixing. Alternative MSA #3 (Enhanced In Situ Bioremediation with Chemical Reduction) would be the easiest option to construct, but is expected to have more long-term operational issues with regard to addressing hot spots of contamination. All alternatives have readily available equipment, specialty vendors with expertise in implementation, and can be effectively monitored. MSA #2 provides the best operational flexibility and technical reliability.

Secondary Source Area - All of the action alternatives evaluated for the SSA are implementable with only minor issues. All of the remedies depend on proven and reliable technology that is easy to construct. Enhanced In Situ Bioremediation with Chemical Reduction (Alternative SSA #3) and In Situ Chemical Oxidation (SSA #2) present a greater challenge to operate due to the hydrogeology of the saprolite and Transition Zone. Alternative SSA #4 (In Situ Thermal Treatment) has several real-time performance feedback mechanisms, including in situ temperature profiles and recovered fluid concentrations to help optimize implementation. Alternatives SSA #2 and SSA #3 require more extrapolation of performance monitoring data in order to optimize the remedies.

Residential Water - Extension of die municipal water line is implementable. Depending on the route selected, agreements with the Norfolk Southern Railway or private property owners (or both) would be needed to construct the water line.

COST

Cost estimates for each alternative are summarized in the tables below. Costs for the implementation of Five- Year-Reviews and groundwater monitoring are included as site-wide costs. These O&M costs were estimated separately as they apply to all remedy alternatives since waste will remain in place at the Site. They are not included in the tables below but are included in the costs for the preferred remedial alternatives. Long-term O&M costs were computed using a 7 percent discount rate to account for the time value of money.

ESTIMATED COSTS FOR CONTAMINATED SOIL REMEDIAL ALTERNATIVES IN THE UNSATURATED ZONE

Activity Alternative UZ #1 Alternative UZ #2 Alternative UZ #3 Alternative UZ #4

Estimated Capital Cost $0 $1,042,598 $2,325,343 $2,422,899

Estimated Annual O&M Costs $41,978 $855,011 $770,743 $808,803

Net Present Value $42,000 $1,897,600 $3,096,100 $3,231,700

ESTIMATED COSTS FOR COP^TAMINATED GROUNDWATER AND CONTIGUOUS SOIL REMEDIAL ALTERNATIVES IN THE MAIN SOURCE AREA Activity Alternative MSA #1 Alternative MSA #2 Alternative MSA #3 Alternative MSA #4

Estimated Capital Cost $0 $2,691,406 $2,078,109 $4,445,618

Estimated Annual O&M Costs $41,978 $0 $701,118 $180,159

Net Present Value $42,000 $2,691,400 $2,779,200 $4,625,800

Community Involvement Plan Page 54 September 2018 Proposed Plan for ROD Ram Leather Care Site May 2018 ESTIMATED COSTS FOR CONTAMINATED GROUNDWATER AND CONTIGUOUS SOIL REMEDIAL ALTERNATIVES IN THE SECONDARY SOURCE AREA Activity Alternative SSA #1 Alternative SSA #2 Alternative SSA #3 Alternative SSA #4

Estimated Capital Cost $0 $3,414,717 $4,064,658 $15,326,936

Estimated Annual O&M Costs $41,978 $150,281 $1,194,299 $538,983

Net Present Value $42,00 $3,565,000 $5,259,00 $15,865,900

ESTIMATED COSTS FOR REMEDIAL ALTERNATIVES FOR RESIDENTIAL WATER Alternative RW #2, Alternative RW #2, Alternative RW #2, Activity Alternative RW #1 Option 1 Option 2 Option 3 Estimated Capital Cost $0 $198,000 $215,164 $274,561

Estimated Annual O&M Costs $0 $0 $0 $0

Net Present Value $0 $198,000 $215,200 $274,600

SUMMARY OF PREFERRED ALTERNATIVE

Using the above information/assumptions, the Agency’s Preferred Alternative for the Ram Leather Care Superfimd Site is the combination of the alternatives listed below. Elements common to the alternatives fm* each CMZ are site-wide activities that include long-term groundwater monitoring, five-year reviews, and placement of ICs on the Site to provide increased public awareness of the Site’s hazards, minimize the potential for exposure to contaminated groundwater and soil, and restrict access to some portions of the Site where contaminated soil may remain in place.

• The Preferred Remedial Alternative for contaminated soil in the UZ is Alternative UZ #2 - Soil Vapor Extraction (SVE). • The Preferred Remedial Alternative for contaminated saturated soil and groimdwater in the MSA is Alternative MSA M-In Situ Thermal Treatment. • The Preferred Remedial Alternative for contaminated saturated soil and groundwater in the SSA is Alternative SSA #4 - 7n Situ Thermal Treatment with EISB Biobarriers. • The Preferred Remedial Alternative for residential water is Alternative RW #2 - Municipal Water Line Extension, construction option 3.

Figure 9 shows the locations of the UZ, MSA, and SSA treatment areas; Figure 10 shows the approximate location of the municipal water line to be installed. In situ thermal treatment will be used to treat contamination within the Main Source Area zone, the portion of the Secondary Source Area where total chlorinated ethene concentratioiK exceed 4,000 pg/L, and the portion of the Unsaturated Zone that lies within the 4,000 pg/L boundary. The remainder of the Unsaturated Zone would be treated using Soil Vapor Extraction. The portion of the Secondary Source Area outside of the 4,000 pg/L contour will be treated using Enhanced In Situ Bioremediation barriers.

This Preferred Alternative also includes the following actions:

• Demolition of the remaining building to accommodate work in the soils below, grub and fence the

Community Involvement Plan Page 55 September 2018 Proposed Plan for ROD 25 Rm Leather Care Site May 2018 facility; • Continued SVE operations for 1 to 4 years; * Evaluation of remedial progress through monitoring and recommendations for limited scale treatment with biobarriers.

Because in situ thermal treatment will be used to treat several overlapping CMZs (for example, the MSA is fully contained within the SSA thermal treatment area), the cost to implement the Preferred Alternative is less than the sum of the costs estimated independently for Alternatives UZ #2, MSA #4, and SSA #4. The estimated total cost of this Preferred Remedial Alternative is $16,950,540.

Total Cost of Preferred Remedial Alternative Location Alternative Name Net Present Yalne UZ SVE (only a portion used) $759,040 MSA In Situ Thermal Treatment $0.00 SSA In Situ Thermal Treatment with EISB $15,865,900 RW Water Line Extention Option 3 $274,600 Jite-Wide Costs (5-Year Sampling and Reviews, ICs, etc...) $51,000 Total $16,950,540

PUBLIC PARTICIPATION

The public meeting for the Proposed Plan will begin at 6:00 p.m. on Tuesday, May 22,2018, at the Fellowship Baptist Church at 11416 Albemarle Road, Mint Hill, North Carolina.

EPAand NCDEQhave provided information regarding the cieanup of the Site to the pubiic through Fact Sheets, pubiic meetings, announcements in the Chariotte Observer and the Administrative Record file, in addition to reading this Proposed Pian, EPA and NCDEQ encourage the pubiic to gain a more comprehensive understanding of the Site and the Superfund activities that have been conducted at the Site by reviewing the documents contained in the Administrative Record/information Repository.

For further information on the Site, please contact:

Beverly Stepter Remedial Project Manager (404) 562-8816 or (800) 435-9233 E-mail: [email protected]

Angela Miller Community Involvement Coordinator (404) 562-8561 or (800) 435-9233 E-mail: [email protected] US EPA Region 4 Sam Nunn Federal Office Building 61 Forsyth Street, SW Atlanta, GA 30303-8960

Community Involvement Plan Page 56 September 2018 Proposed Plan for ROD Ram Leather Care Site May 2018 DOCUMENT INFORMATION

The Administrative Record contains all the information used by the Agency to select a Remedial Action. Copies of the Administrative Record are kept at:

Mint Hill Branch Library 6840 Matthews - Mint Hill Road Mint Hill, NC 28227

Phone: 704-416-5200 Hours: Monday - Thursday 9 a.m. - 8 p.m. Friday and Saturday 9 a.m. - 5 p.m. Sunday Closed.

U.S. Environmental Protection Agency Region IV - Records Center 61 Forsyth Street, SW Atlanta, Georgia 30303-3104 Phone: 404-562-8816 Hours: Monday - Friday 8 a.m. - 5 p.m. Saturday and Sunday Closed.

Community Involvement Plan Page 57 September 2018 Table 1: Summary of Reasonable Maximum Exposure, Human Health Risks and Hazards, Ram Leather Care

Hazard Location Receptor Cancer Risk Quotient'

Future Onsite Lifetime 1 X 10'^ 497 Resident Onsite Groundwater Future Onsite Industrial 1 X 10-^ 89 / Commercial Worker Future Onsite Industrial Onsite Indoor Air 1 X 10'^ 89 / Commercial Worker Future Construction 5 X 10" <1 Excavation Trench Worker Future Utility Worker IxlO-* <1 Notes: Source: HHRA(2017). Shading indicates unacceptable cancer risk or non-cancer hazard. ' Hazard Quotients are based on target organ hazard indices.

Community Involvement Plan Page 58 September 2018 Table 2: Chemicals of Concern Potentially Requiring Action in Groundwater, Ram Leather Care

HHRA Risk-Based Groundwater RGOs Oig/L) HHRA Chemical of MCL NCAC 2L Residential Non- Residential Cancer Concern (Hg/L) (lig/L) Cancer Hazard Risk Levels Levels 1x10^ HQ=1 Benzene 5 1 9.2E+01 NA

Bromodichloromethane 80 0.6 4.6E-K)1 NA

1,1 -Dichloroethene 7 7 NA 7.9E+02 cis-1,2-Dichloroethene 70 70 NA 5.1E+01

trans-1,2-Dichloroethene 100 100 NA 5.3E+02

Tetrachloroethene 5 0.7 1.9E-t-03 8.7E+01

Trichloroethene 5 3 7.4E+01 7.8E+00

Vinyl chloride 2 0.03 5.1E+00 7.5E+01 Notes: Sources; National Primary Drinking Water Standards; 15ANCAC 02L.0202; HHRA Table 6-1. HHRA - Human Health Risk Assessment; MCL - Federal Maximum Contaminant Level; |ig/L - micrograms per liter; NCAC 2L - North Carolina Groundwater Standard promulgated under 15ANCAC 02L .0202; RGO -Remedial Goal Option; NA- not applicable

Community Involvement Plan Page 59 September 2018 Table 3: Chemicals of Concern Potentially Requiring Action for Indoor Air, Ram Leather Care

EPA Regional Screening HHRA Risk-Based Indoor Air Remedial Goal Options Level (^g/m^ Residential Air Industrial Air Non- Non- HHRA COC Cancer Cancer Residential Industrial Cancer Cancer Risk Risk Air Air Hazard Hazard Levels Levels 1x10^ Levels IxlO"* Levels HO=l HO-1 Tetrachloroethene 4.2E+00 1.8E+01 l.lE+03 4.2E+01 4.7E+03 1.8E+02 Trichloroethene 2.1E-01 8.8E-01 5.5E+01 2.1E+00 3.0E+02 8.8E+00 (Total)

Vinyl chloride 1.7E-01 2.8E+00 3.2E+01 l.OE+02 2.8E+02 NA (Lifetime) Notes: EPA Regional Screening Level Tables (TR= lE-06; HQ = 0.1) Nov. 2017; HHRA Tables 6-4 and 6-5. COC - chemicals of concern; ng/m^ - micrograms per cubic meter; HHRA - Human Health Risk Assessment; HQ - hazard quotient; NA - not applicable.

Ram Leather Care Site Community Involvement Plan Page 60 September 2018 U.S. Environmental Protection Agency North Site Management Branch 61 Forsyth Street, SW Angela Miller, Community Involvement Coordinator Atlanta, Georgia 30303 Beverly Stepter, Remedial Project Manager Official Business Penalty for Private Use $300

Ram Leather Care Site Community Involvement Plan Page 61 September 2018