N6247241_GRC North Plot_Sandusky OH_ESA Report_FINAL_Revised - signed (1).pdf

Phase I Environmental Site Assessment GRC-Armstrong Test Facility (ATF) – North Plot

Taylor Road and Ransom Road

Sandusky, Erie County, Ohio

March 19, 2025 | Terracon Project No. N6247241

Prepared for:

Firelake - Arrowhead NASA Services 21000 Brookpark Road Cleveland, Ohio

Prepared by:

Terracon Consultants, Inc.

Cleveland, Ohio

12460 Plaza Drive

Cleveland, Ohio 44130-1057

P 216-459-8378

Terracon.com

March 19, 2025

Firelake - Arrowhead NASA Services 21000 Brookpark Road Cleveland, Ohio 44135-3127

Attn: Mr. Ted Kemer E: ted.kemer@nasa.gov

Re: Phase I Environmental Site Assessment GRC-Armstrong Test Facility (ATF) – North Plot Taylor Road and Ransom Road Sandusky, Erie County, Ohio Terracon Project No. N6247241

Dear Mr. Kemer:

Terracon Consultants, Inc. (Terracon) is pleased to submit the enclosed Phase I Environmental Site Assessment (ESA) report for the above-referenced subject property (hereinafter known as the ‘site’). This assessment was performed in accordance with Terracon Proposal No. PN6247241 dated July 3, 2024.

We appreciate the opportunity to be of service to you on this project. In addition to ESA services, our professionals provide other environmental, geotechnical, construction materials, and facilities services on a wide variety of projects locally, regionally, and nationally. For more detailed information on all of Terracon’s services please visit our website at www.terracon.com. If there are any questions regarding this report or if we may be of further assistance, please do not hesitate to contact us.

Sincerely, Terracon Consultants, Inc.

Kelly M. MacWhinnie Stacy L. Baron-Vatty Project Manager Senior Associate

Department Manager – Due Diligence

Attachments

GRC-Armstrong Test Facility (ATF) – North Plot | Sandusky, Ohio

March 19, 2025 | Terracon Project No. N6247241

Facilities | Environmental | Geotechnical | Materials

Table of Contents Executive Summary .......................................................................................................... i

Findings and Opinions ................................................................................ i

Conclusions ............................................................................................. ix

1.0 Introduction

1.1 Site Description

1.2 Scope of Services

1.3 Standard of Care

1.4 Additional Scope Limitations, ASTM Deviations, and Data Gaps

1.5 Reliance

1.6 Client Provided Information

2.0 Physical Setting

3.0 Historical Use Information

3.1 Historical Topographic Maps, Aerial Photographs, and Sanborn Maps

3.2 Historical City Directories

3.3 Site Ownership

3.4 Title Search

3.5 Environmental Liens and Activity and Use Limitations

3.6 Interviews Regarding Current and Historical Site Uses

3.7 Prior Report Review

4.0 Records Review

4.1 Federal and State/Tribal Databases

4.2 Local Agency Inquiries

5.0 Site Reconnaissance

5.1 General Site Information

5.2 Overview of Current Site Occupants

5.3 Overview of Current Site Operations

5.4 Site Observations

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6.0 Adjoining Property Reconnaissance

7.0 Additional Services

7.1 Visual Observations for Suspect Asbestos

7.2 Radon Records Review

7.3 Visual Observations for Suspect Lead-Based Paint

7.4 Lead in Drinking Water Records Review

7.5 Wetland Records Review

7.6 Threatened/Endangered Species Records Review

7.7 Historic Properties/Archaeological Resources Review

7.8 Visual Observations for Hazardous Material Items

7.9 Review of Per- and Polyfluoroalkyl Substances (PFAS)

8.0 Declaration

9.0 References

Appendices

APPENDIX A Exhibit 1: Topographic Map

Exhibit 2: Site Diagram, Exhibit 3: Site Buildings and Structures

APPENDIX B Site Photographs

APPENDIX C Historical Documentation and User Questionnaire

APPENDIX D Environmental Database Information

APPENDIX E Credentials

APPENDIX F Description of Terms and Acronyms

Tables

TABLE 1 Bureau of Underground Storage Tank Regulations (BUSTR) Underground Storage Tanks (USTs)

TABLE 2 NASA GRC-ATF Areas of Evaluation/Remediation

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TABLE 3 Site Description

TABLE 4 Client Questionnaire Responses

TABLE 5 Physical Setting Information

TABLE 6 Historical Maps and Aerial Photographs

TABLE 7 Historical City Directories

TABLE 8 Chain-of-Title

TABLE 9 Interview

TABLE 10 NASA GRC-ATF Areas of Evaluation/Remediation

TABLE 11 Federal and State/Tribal Databases Listed Facilities

TABLE 12 BUSTR USTs

TABLE 13 Local Agency Inquiries

TABLE 14 General Site Information

TABLE 15 Site Characteristics

TABLE 16 Heating and Cooling Systems

TABLE 17 Drums, Barrels, and/or Containers

TABLE 18 Transformers

TABLE 19 Adjoining Properties

TABLE 20 Suspect Asbestos Containing Materials (ACM)

TABLE 21 Lead-Based Paint (LBP)

TABLE 22 Threatened & Endangered Species

Figures

EXHIBIT 1 Topographic Map

EXHIBIT 2 Site Diagram

EXHIBIT 3 Site Buildings and Structures

GRC Armstrong Test Facility (ATF) – North Plot | Sandusky, Ohio

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Executive Summary

This Phase I Environmental Site Assessment (ESA) was performed in accordance with Terracon Proposal No. PN6247241 dated July 3, 2024, and was conducted consistent with the procedures included in ASTM E1527-21, Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process. The purpose of this ESA was to assist the client in developing information to identify RECs in connection with the site as reflected by the scope of this report. The ESA was conducted under the supervision or responsible charge of Stacy L. Baron-Vatty, Environmental Professional. Kelly M.

MacWhinnie performed the site reconnaissance on September 24, 2024.

Findings and Opinions

A summary of the findings is provided below. It should be recognized that details were not included or fully developed in this section, and the report must be read in its entirety for a comprehensive understanding of the items contained herein.

Site Description and Use

The approximately 870-acre site is bordered by Taylor Road to the southeast and by Ransom Road to the west in Sandusky (Perkins Township), Erie County, Ohio. The site consists of a portion of the NASA GRC at Neil A. Armstrong Test Facility (GRC-ATF) and is developed with several former test facility buildings and areas, currently utilized for storage and maintenance operations. Pentolite Road traverses the central portion of the site; Maintenance Road traverses the south portion of the site; Patrol Road traverses the north site boundary; Taylor Road traverses the southeast site boundary; and Ransom Road traverses the west site boundary. A large pond (Reservoir #1) is in the southeast portion of the site. The remainder of the site consists of wooded and brush-covered land, ditches, and marsh areas.

According to client-provided documentation and information obtained from the Erie County Auditor’s website, the site is situated in the north-central portion of a larger 6,436.5667-acre parent parcel of land identified as PPN: 32-60001.000 currently owned by United States of America NASA.

Historical Information

Based on a review of historical information, in the early-1900s, two small structures, presumably dwellings, occupied the southeast corner of site, and ditches/drainageways traversed the central and east portions of the site. In the late-1930s, the site was occupied by brush-covered and wooded land, agricultural fields, and drainageways/ditches.

Between 1938 and 1941, the U.S. Army established the site as “Plum Brook Ordnance

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Works”, utilized for the manufacturing of trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), and pentolite. TNT production was conducted from 1941 to 1945, after which buildings and production lines were decontaminated and decommissioned by the Army. In 1955, the National Advisory Committee for Aeronautics (NACA) acquired the site for the construction of a nuclear research reactor facility, which was transferred to NASA in 1958. According to the 2023 Leidos Final Records Review report, “NACA’s original interest in the site was as a testing location for high-energy rocket engines and nuclear power systems. Other activities at NASA over the years have included the development of special pumps for space applications, rocket engine research, space vehicle testing, cryogenic testing, wind tunnel testing, and related aerospace research. The nuclear reactor research facility operated at the site until the early-2000s, at which time the nuclear reactor and associated facilities were decommissioned and razed. The site is currently occupied by 15 buildings, primarily utilized for storage and vehicle maintenance activities.

Records Review

The database report lists Plum Brook Ordnance Works / US NASA Plum Brook / NASA Neil A. Armstrong Test Facility located at 6100 Columbus Avenue (site and surrounding areas) as a Formerly Used Defense Site (FUDS), Division of Environmental Response and Revitalization (DERR), Voluntary Cleanup Program (VCP), VAPOR, Superfund Enterprise Management System (SEMS)-Archive, Corrective Action Report (CORRACTS), Resource Conservation and Recovery Act (RCRA)-Treatment, Storage, and Disposal Facility (TSDF), RCRA-Large Quantity Generator (LQG), 2020 Cor Action, PCB Activity Database System (PADS), Integrated Compliance Information System (ICIS), Facility Index System (FINDS), Enforcement and Compliance History (ECHO), Docket Hazardous Waste Compliance (HWC), and Manifest site. These listings are associated with the historical on-site and surrounding DoD facility and the current NASA facility which encompasses approximately 9,100-acres. Listings and associated environmental assessments limited to the site are summarized under the Previous Reports heading of this Executive Summary and are discussed in detail in Section 3.7 of this report.

There is one land use control (LUC), which is a sitewide groundwater use restriction at ATF that Ohio EPA required to closeout the FUDS site. According to Ms. Stacey Yanetta, client representative, “The LUC was inserted in the GRC Master Plan, but the LUC has not been added to title due to GSA policy that such LUCs be added through the property transfer process. Below is the text from the GRC Master Plan that describes the LUC:

The remediation efforts at Neil A. Armstrong Test Facility (GRC-ATF) by NASA and the Army Corps of Engineers return most areas to residential clean-up standards, but the groundwater presents a costly and near impossible remedial action. Groundwater underlying GRC-ATF shall not be extracted or used for any purpose, potable or otherwise, except for

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Facilities | Environmental | Geotechnical | Materials iii investigation, monitoring or remediation of groundwater, or in conjunction with construction or excavation activities or maintenance of subsurface utilities. Prior to transfer or conveyance of GRC-ATF or any portion thereof, the General Services Administration (GSA) and NASA shall ensure that the prospective purchaser or transferee: i) is aware of the environmental conditions of the property; and ii) agrees, as a condition of the purchase/transfer, to enter into an environmental covenant with the State of Ohio prohibiting the extraction or use of groundwater underlying GRC- ATF for any purpose potable or otherwise, except for investigation, monitoring or remediation of groundwater, or in conjunction with construction or excavation activities or maintenance of subsurface utilities.

In addition, prior to transfer or conveyance of any portion of GRC-ATF that does not meet residential soil standards, GSA and NASA shall ensure that the prospective purchaser or transferee also agrees, as a condition of the purchase/transfer, that the environmental covenant with the State of Ohio shall also prohibit residential use of such property, in addition to the aforementioned groundwater extraction / use prohibition.

The existing LUC associated with a sitewide groundwater use restriction represents a Controlled Recognized Environmental Condition (CREC) to the site.

Several underground storage tanks (UST) systems were previously utilized at the site.

Information available for the site from the Bureau of Underground Storage Tank Regulations (BUSTR) is included in the table below.

Table 1 – BUSTR USTs

Release Incident Date Location USTs Removed Status

229369-01;

22007802-N00001

22007802-

N00002; 2200804- N00002

July 1989 Near Building

9,000-gallon gasoline (Tank 7132-1)

9,000-gallon gasoline (Tank 7132-2)

9,000-gallon diesel (Tank 7132-3

No Further Action (NFA)

229369-02 / 22007804-N00001

July 1990 Former Building

9,000-gallon diesel (Tank

36) Closure (CLO)

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Release Incident Date Location USTs Removed Status

229369-04, reassigned

Incident #s 22- 007802-03, 22007802-04, 22007802-06, 22007803-01, and 22007808-01

September

East of Former Building 7121

3,000-gallon waste oil and solvent (Tank 28), 770-gallon toluene (Tanks 29, 30, 31), 1,500-gallon waste oil (Tank 32)

Further regulatory activity referred to

OEPA due to solvent and waste oil contamination

229369-07 / 22007802-N00005

September

Former Building 8133 Pump Station (SE portion of site)

250-gallon gasoline (Tank 39)

NFA

22007807-N00001 September

Near Building

500-gallon used oil, 7,900-gallon gas/diesel, 7,900-gallon waste oil and solvent

CLO

229369-10 / 22007805-N00001

February

Building 8951

12,000-gallon jet fuel (Tank 37)

12,000-gallon jet fuel (Tank 38)

NFA

220007806- N00001

March

Former Building 8133 Pump Station (SE portion of site)

250-gallon (contents unknown)

NFA

22007804-N00003

22007804-N00004

December 2002 and January

East of Building

8,000-gallon gasoline (closed in place), 8,000-gallon diesel

NFA

Remediation activities associated with Release Incident #229369-04, reassigned Incident #s 22-007802-03, 22007802-04, 22007802-06, 22007803-01, and 22007808-01 (Tanks 28, 29, 30, 31, and 32) are summarized under the Previous Reports heading of this Executive Summary and are discussed in detail in Section 3.7 of this report. Based on the BUSTR file review and current regulatory statuses (NFA), the remaining former USTs represent a HREC to the site. In addition, the existing closed-in-place UST located east of Building 7132 also represents a development consideration for the site. If construction activities are planned around the closed-in-place UST, Terracon recommends that the UST be removed in accordance with applicable regulations.

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The remaining facilities listed in the database report do not appear to represent RECs to the site at this time based upon regulatory status, apparent topographic gradient, and/or distance from the site.

Previous Reports

The client provided Terracon with copies of several previous environmental reports completed for the site, including groundwater and subsurface assessments. In addition, a Final Records Review Report, which provides detailed summaries of all environmental remediation and closure activities that have occurred at the site, a Clean Closure Certification Report (Garage and Maintenance Area), and a Final Status Survey Report (Plum Brook Reactor Facility) were also provided by the client for review and are summarized below.

The 2023 Final Records Review Report provided detailed summaries of all environmental remediation and closure activities that have occurred by U.S. Army Corps of Engineers (USACE) as part of the Defense Environmental Restoration Program Formerly Used Defense Site (DERP-FUDS) program, which was established to address properties that have been contaminated by U.S. Department of Defense (DoD) activities. Since 1989, numerous soil and groundwater remediation projects have been conducted under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), the Resource Conservation and Recovery Act (RCRA), and the State of Ohio Division of State Fire Marshal’s Bureau of Underground Storage Tank Regulations (BUSTR). While the Final Records Review Report includes an evaluation of approximately 6,436.5667-acres of NASA GRC-ATF, areas of evaluation/remediation limited to the site are summarized in the table below and are discussed in detail in Section 3.7 of this report.

Table 2 – NASA GRC-ATF Areas of Evaluation/Remediation

Project Name Location Status

Wastewater

Treatment Plant #1 SE portion of site, along the north side of Maintenance Rd

Unrestricted use (residential) for soils, sediment, and surface water; insufficient yield for potable use for groundwater, no action recommended

Pentolite Area Waste Lagoons

(PAWL)

Central portion of site, along the north side of Pentolite Rd

NFA

Red Water Ponds

Area SE portion of site, south of

Pentolite Rd NFA recommended

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Project Name Location Status

1821 Ash Pit #1 SE portion of site, along the south side of Maintenance Rd

NFA

1825 Garage Maintenance South-central portion of site, along the north side of Maintenance Rd

NFA

Based on review of the Final Records Review Report and due to the current regulatory statuses (NFA and NFA recommended), historical operations associated with on-site DoD activities represent a historical recognized environmental condition (HREC) to the site. In addition, development considerations and business environmental risks associated with historic DoD operations include the following:

Soil vapor evaluations have not been completed at on-site historical DoD areas listed above. Terracon considers this a development consideration for the site, and further evaluation would be recommended if development activities are planned in these areas.

Below-grade concrete and utility infrastructure were left in place at various on-site historical DoD areas listed above. Terracon considers this a development consideration for the site, and further evaluation would be recommended if development activities are planned in these areas.

Asbestos or ACM evaluations have not been completed at on-site historical DoD areas listed above. Terracon considers this a business environmental risk for the site.

The 2019 Clean Closure Certification Report was completed to establish that NASA reached clean closure for past activities at the Waste Management Unit (WMU) at Former Building 7121 (former USTs #28, #29, #30, and #31) and the WMU at Building 7131 (former UST #32). VOC contamination was identified in the area associated with the former use of UST systems and quarterly and annual groundwater sampling and monitoring occurred between 2004 and 2017. In addition, a Vacuum-Enhanced Groundwater Extraction (VEGE) system was utilized in the area between 2004 and 2009, and excavation and removal of contaminated soil and groundwater was completed. In 2018, a revised Amended Closure Plan (ACP) Version 7.0 and a Final Human Health Risk Assessment (HHRA) for Soil and Groundwater were submitted to the Ohio Environmental Protection Agency (OEPA). OEPA approved the ACP on November 23, 2018, and the HHRA on April 4, 2019. In their approval correspondence, OEPA stated that while the site achieved clean closure (no unacceptable health risk for potential future residential land use), “an environmental covenant will be implemented to restrict all future ground water use in the event of a property transfer.”

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Based on this information, the environmental covenant associated with restriction of groundwater use represents a CREC to the site.

The 2012 Final Status Survey Report (FSSR) provided an overview of the characterization, surveying, and cleanup activities of the Plum Brook Reactor Facility, previously located in the central portion of the site, reviewed and evaluated by the Nuclear Regulatory Commission (NRC). In the report, the following conclusion is made:

NASA demonstrated that the dose to a member of the critical group from residual radioactivity in sediments from Plum Brook is well below the dose criterion for unrestricted use in 10 CFR 20.1402. The goal of NASA is to release the facility for unrestricted use in compliance with the criteria in the US NRC 10CFR20 Subpart E regulation. The principal criterion is that the dose to future site occupants will be less than 25 mrem/y. Subpart E also requires that residual contamination be reduced to levels as low as reasonably achievable (ALARA). As described in the FSS Plan, the 25 mrem/y criterion is satisfied by collection of measurements to show that residual contamination levels are below Derived Concentration Guideline Levels (DCGLs). The DCGLs for residual contamination in soil and on structure surfaces have been established in accordance with the PBRF Final Status Survey Plan [NASA 2007].

A correspondence dated October 10, 2012, signed by Ms. Lydia Chang, Acting Deputy Director with the Decommissioning and Uranium Recovery Licensing Directorate, Division of Waste Management and Environmental Protection, Office of Federal and State Materials and Environmental Programs states that the NRC concluded that the decommissioning process is complete, has terminated the two licenses for the decommissioned NASA PBRF reactors, and has released the site for unrestricted use. Based on this information and due to the regulatory status (unrestricted closure), historical operations associated with the former on-site nuclear reactor facility represent a HREC to the site.

Site Reconnaissance

During the site reconnaissance, Terracon observed the following:

Two “T”-shaped concrete patches” indicative of in-ground hydraulic lifts, were observed in the east portion of Building 7131 (Garage). Shop personnel believed the west lift had been removed, but components of the east lift could still be in place. Mr. Rick Bressler, Construction Manager with Firelake Construction, Inc., NASA Facilities Division (site representative) and shop personnel were unaware of the date of removal activities for the lifts or if any associated sampling activities had been completed. It is possible the in-ground lifts were utilized since construction of the building in 1943. The long-term use of the in-ground lifts and

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Facilities | Environmental | Geotechnical | Materials viii potential releases of hazardous substances and/or petroleum products associated with the in-ground lifts and associated hydraulic components represents a REC to the site.

An approximate 15’ x 3’ sub-grade mechanic pit was observed in the east portion of Building 7131 (Garage). Terracon was unable to view the interior of the mechanic pit during the site reconnaissance due to a wooden cover and vehicle positioning.

It is possible the mechanic pit has been in use since construction of the building in 1943. The long-term use of the mechanic pit and potential releases of hazardous substances and/or petroleum products associated with vehicle repair activities within, and in the vicinity of the mechanic pit represents a REC to the site.

A single-stall wash bay was observed in the central portion of Building 7131 (Garage). An approximate 10-foot-long trench drain was observed within the wash bay. According to Mr. Bressler, a previous dye test revealed that the trench drain discharges to a stormwater ditch situated north of the building. NASA personnel confirmed that the drain discharges to a ditch north of the building. It is possible the wash bay has been in use since construction of the building in 1943. The long-term use of the wash bay and potential releases of hazardous substances, including PFAS, and/or petroleum products associated with vehicle and equipment cleaning activities within the wash-bay and the associated stormwater ditch discharges represent a REC to the site.

Adjoining Properties

The site is bordered to the north by residential development, Sandusky Church of God, and an agricultural field; to the east by residential development and wooded and brush-covered land; to the south by GRAC-ATF substation and support building/power house (Buildings 8531 and 8562), GRC-ATF warehouse (Building 9206), GRC-ATF CCL Control Building (Building 2921), an exterior storage yard, and grass-covered, brush-covered, and wooded land; and to the west by wooded and grass-covered land. RECs associated with the site originating from current off-site operations were not identified.

Additional Services

Per the agreed scope of services, the following additional services as outlined in the proposal, including items described in Section 13.0 (Non-Scope Considerations) of ASTM E1527-21, were conducted:

Visual observations for suspect asbestos Radon records review Visual observations for suspect lead-based paint

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Lead in drinking water records review Wetlands records review Threatened/endangered species records review Historic properties/archaeological resources review Visual observations for hazardous material items Review of per- and polyfluoroalkyl substances (PFAs)

Conclusions

We have performed a Phase I ESA consistent with the procedures included in ASTM Practice E1527-21 at the GRC-ATF – North Plot located at Taylor Road and Ransom Road in Sandusky, Erie County, Ohio, the site. The following REC, HRECs and CREC were identified in connection with the site:

The in-ground lifts, maintenance pit, and wash bay located in Building 7131 – Garage represent a REC to the site, as the potential release of petroleum products and/or hazardous substances, including PFAS, associated with maintenance operations may have impacted the site.

Historical on-site DoD operations and associated environmental remediation and closure activities represent a HREC to the site.

Removal and closure activities associated with several former UST systems and one existing UST system (closed-in-place) issued NFA status from BUSTR represent a HREC to the site.

Historical operations associated with the former on-site nuclear reactor facility represent a HREC to the site.

The existing LUC associated with a sitewide groundwater use restriction represents a CREC to the site.

Soil vapor evaluations have not been completed at on-site historical DoD areas. Terracon considers this a development consideration for the site.

Below-grade concrete and utility infrastructure were left in-place at various on-site historical DoD areas. Terracon considers this a development consideration for the site.

Asbestos or ACM evaluations have not been completed at on-site historical DOD areas.

Terracon considers this a business environmental risk for the site.

The existing closed-in-place UST system located east of Building 7132 (south central portion of site) represents a development consideration for the site.

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1.0 Introduction

1.1 Site Description

Table 3 – Site Description

Site Name GRC-ATF – North Plot

Site Location/Address Taylor Road and Ransom Road

Parcel Numbers #32-60001.000

Land Area Approximately 870-acres

Site Improvements Several storage and maintenance buildings (listed in Section 5.1), roadways, paved access drives and exterior storage areas, a large pond, and drainage ditches

Anticipated Future Site Use Enhance Use Lease (EUL)

Reason for the ESA Due diligence

The location of the site is depicted on Exhibit 1 of Appendix A, which was reproduced from portions of the 1969 Kimball, Ohio (OH) and 1979 Sandusky, OH United States Geologic Survey (USGS) 7.5-minute series topographic maps. The site and adjoining properties are depicted on the Site Diagram, which is included as Exhibit 2 of Appendix A.

1.2 Scope of Services

This Phase I Environmental Site Assessment (ESA) was performed in accordance with Terracon Proposal No. PN6247241 dated July 3, 2024, and was conducted consistent with the procedures included in ASTM E1527-21, Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process. The purpose of this ESA was to assist the client in developing information to identify RECs in connection with the site as reflected by the scope of this report. Recognized environmental conditions are defined by ASTM E1527-21 as “(1) the presence of hazardous substances or petroleum products in, on, or at the subject property due to a release to the environment; (2) the likely presence of hazardous substances or petroleum products in, on, or at the subject property due to a release or likely release to the environment; or (3) the presence of hazardous substances or petroleum products in, on, or at the subject property under conditions that pose a material threat of a future release to the environment.” This ESA includes consideration of the movement of hazardous substances and petroleum products in any form, including migration of vapor in the subsurface. A de minimis condition is not a recognized environmental condition.

This purpose was undertaken through user-provided information, a regulatory database review, historical and physical records review, interviews (including local government

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Facilities | Environmental | Geotechnical | Materials 11 inquiries, as applicable), and a visual noninvasive reconnaissance of the site and adjoining properties. Limitations, ASTM deviations, and significant data gaps (if identified) are noted in the applicable sections of the report.

Review of Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS)

PFAS are a family of compounds which are considered emerging contaminants of concern due to their mobility and longevity in the environment. PFAS has been used in many products, including but not limited to fire-fighting foam, anti-stick coatings, stain and water-repellent coatings, electroplating, and paper products, among others. On July 8, 2024, US EPA designated two PFAS compounds, perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), including their salts and structural isomers, as hazardous substances under CERCLA; accordingly, PFOA and PFOS was evaluated within the scope of E1527-21. Please note that PFAS compounds are ubiquitous in the environment and this limited review is not to be construed as confirmation that PFAS compounds are not present in, at or under the site.

1.3 Standard of Care

This ESA was performed in accordance with generally accepted practices of this profession, undertaken in similar studies at the same time and in the same geographical area. We have endeavored to meet this standard of care, but may be limited by conditions encountered during performance, a client-driven scope of work, or inability to review information not received by the report date. Where appropriate, these limitations are discussed in the text of the report, and an evaluation of their significance with respect to our findings has been conducted.

Phase I ESAs, such as the one performed at this site, are of limited scope, are noninvasive, and cannot eliminate the potential that hazardous, toxic, or petroleum substances are present or have been released at the site beyond what is identified by the limited scope of this ESA. In conducting the limited scope of services described herein, certain sources of information and public records were not reviewed. It should be recognized that environmental concerns may be documented in public records that were not reviewed. No ESA can wholly eliminate uncertainty regarding the potential for RECs in connection with a property. The performance of this practice is intended to reduce, but not eliminate, uncertainty regarding the potential for RECs. No warranties, express or implied, are intended or made. The limitations herein must be considered when the user of this report formulates opinions as to risks associated with the site or otherwise uses the report for any other purpose. These risks may be further evaluated – but not eliminated – through additional research or assessment. We will, upon request, advise you of additional research or assessment options that may be available and associated costs.

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1.4 Additional Scope Limitations, ASTM Deviations, and Data Gaps

Based upon the agreed-on scope of services, this ESA did not include subsurface or other invasive assessments, vapor intrusion assessments or indoor air quality assessments (i.e., evaluation of the presence of vapors within a building structure), business environmental risk evaluations, or other services not particularly identified and discussed herein.

Credentials of the company (Statement of Qualifications) have not been included in this report but are available upon request. Pertinent documents are referred to in the text of this report, and a separate reference section has not been included. Reasonable attempts were made to obtain information within the scope and time constraints set forth by the client; however, in some instances, the information requested is not, or was not, received by the issuance date of the report. Information obtained for this ESA was received from several sources that we believe to be reliable; nonetheless, the authenticity or reliability of these sources cannot and is not warranted hereunder. This ESA was further limited by the following:

Written and/or verbal inquiries were submitted to local agencies regarding the historic environmental use of the site. At the issuance of this report, records had not been received from the Erie County Health Department. The lack of a records review represents a data gap; however, based on other sources of information reviewed, it is not significant.

An evaluation of the significance of limitations and missing information with respect to our findings has been conducted, and where appropriate, significant data gaps are identified and discussed in the text of the report. However, it should be recognized that an evaluation of significant data gaps is based on the information available at the time of report issuance, and an evaluation of information received after the report issuance date may result in an alteration of our conclusions, recommendations, or opinions. We have no obligation to provide information obtained or discovered by us after the issuance date of the report, or to perform any additional services, regardless of whether the information would affect any conclusions, recommendations, or opinions in the report. This disclaimer specifically applies to any information that has not been provided by the client.

This report represents our service to you as of the report date and constitutes our final document; its text may not be altered after final issuance. Findings in this report are based upon the site’s current utilization, information derived from the most recent reconnaissance and from other activities described herein; such information is subject to change. Certain indicators of the presence of hazardous substances, petroleum products or PFAS compounds may have been latent, inaccessible, unobservable, or not present during the most recent reconnaissance and may subsequently become observable (such as after site renovation or development). Further, these services are not to be construed as legal interpretation or advice.

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1.5 Reliance

This ESA report is prepared for the exclusive use and reliance of Firelake - Arrowhead NASA Services and NASA. Use or reliance by any other party is prohibited without the written authorization of Firelake - Arrowhead NASA Services, NASA, and Terracon Consultants, Inc. (Terracon).

Reliance on the ESA by the client and all authorized parties will be subject to the terms, conditions and limitations stated in the proposal, ESA report, and Terracon’s Agreement.

The limitation of liability defined in the Agreement is the aggregate limit of Terracon’s liability to the client and all relying parties.

Continued viability of this report is subject to ASTM E1527-21 Section 4.6. If the ESA will be used by a different user (third party) than the user for whom the ESA was originally prepared, the third party must also satisfy the user’s responsibilities in Section 6 of ASTM E1527-21.

1.6 Client Provided Information

Prior to the site visit, Ms. Stacey Yanetta, client representative, was asked to provide the following user questionnaire information as described in ASTM E1527-21 Section 6:

Table 4 - Client Questionnaire Responses

Client Questionnaire Item Client

Did Not Respond

Client’s Response

N/A* Yes No

Actual Knowledge of Environmental Liens that may encumber the site.

X

Actual Knowledge of Activity Use Limitations (AULs) that may encumber the site.

X

Specialized Knowledge or Experience that is material to a REC in connection with the site.

X

Actual Knowledge of a Lower Purchase Price because contamination is known or believed to be present at the site.

X

Commonly Known or Reasonably Ascertainable Information that is material to a REC in connection with the site.

X

Obvious Indicators of Releases at the site. X *N/A = Not Applicable

According to Ms. Yanetta, “there is one land use control (LUC), which is a sitewide groundwater use restriction at ATF that Ohio EPA required to closeout a FUDS site. The LUC was inserted in the GRC Master Plan, but the LUC has not been added to title due to

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GSA policy that such LUCs be added through the property transfer process. Below is the text from the GRC Master Plan that describes the LUC:

The remediation efforts at Neil A. Armstrong Test Facility (GRC-ATF) by NASA and the Army Corps of Engineers return most areas to residential clean-up standards, but the groundwater presents a costly and near impossible remedial action.

Groundwater underlying GRC-ATF shall not be extracted or used for any purpose, potable or otherwise, except for investigation, monitoring or remediation of groundwater, or in conjunction with construction or excavation activities or maintenance of subsurface utilities. Prior to transfer or conveyance of GRC-ATF or any portion thereof, the General Services Administration (GSA) and NASA shall ensure that the prospective purchaser or transferee: i) is aware of the environmental conditions of the property; and ii) agrees, as a condition of the purchase/transfer, to enter into an environmental covenant with the State of Ohio prohibiting the extraction or use of groundwater underlying GRC-ATF for any purpose, potable or otherwise, except for investigation, monitoring or remediation of groundwater, or in conjunction with construction or excavation activities or maintenance of subsurface utilities. In addition, prior to transfer or conveyance of any portion of GRC-ATF that does not meet residential soil standards, GSA and NASA shall ensure that the prospective purchaser or transferee also agrees, as a condition of the purchase/transfer, that the environmental covenant with the State of Ohio shall also prohibit residential use of such property, in addition to the aforementioned groundwater extraction / use prohibition.

Based on this information and documentation reviewed throughout this report, the LUC associated with a sitewide groundwater use restriction represents a CREC to the site.

2.0 Physical Setting

Table 5 – Physical Setting Information

Physical Setting Information Source

Topography

Site Elevation Approximately 625 to 640 feet above sea level

USGS Topographic Maps, Kimball & Sandusky, OH

Quadrangles, 1969 & 1979 (Appendix A)

Topographic Gradient The site varies in terrain and slopes generally north.

Closest Surface Water

Plum Brook traverses the southeast site boundary. In addition, several ditches and potential wetlands occupy various site areas.

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Physical Setting Information Source

Dominant Soil Characteristics

Soil Type Colwood loam, 0 to 1 percent slopes

USDA Soil Survey accessed September 23, 2024

Description

Parent Material: Glaciolacustrine deposits Properties and qualities Drainage Class: Very poorly drained Permeability: Moderately high

Soil Type Elnora loamy fine sand, 0 to 4 percent slopes

Description

Parent Material: Glaciolacustrine deposits Properties and qualities Drainage Class: Moderately well drained Permeability: High

Geology/Hydrogeology

Formation Delaware Limestone

USGS Mineral Resources

Online Spatial Data, accessed September 23, 2024

Description

Devonian-aged limestone; gray to brown; thin to massive bedded;

argillaceous partings, nodules and layers, carbonaceous, petroliferous odor; as much as 45-feet thick.

Formation Plum Brook Shale

Description

Devonian-aged shale and argillaceous limestone; gray; thin bedded fossiliferous; 0 to 40 feet thick.

Estimated Depth to First Occurrence of Groundwater

Approximately 3 to 10-feet bgs.

Ohio Department of Natural Resources (ODNR) Water Well

Locator accessed September 19, 2024

*Hydrogeologic Gradient Not known - may be inferred to be parallel to topographic gradient (primarily to the north).

* The groundwater flow direction and the depth to shallow, unconfined groundwater, if present, would likely vary depending upon seasonal variations in rainfall and other hydrogeological features. Without the benefit of on-site groundwater monitoring wells surveyed to a datum, groundwater depth and flow direction beneath the site cannot be directly ascertained.

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3.0 Historical Use Information

Terracon reviewed the following historical sources to develop a history of the previous uses of the site and surrounding area, to help identify RECs associated with past uses.

Copies of selected historical documents are included in Appendix C.

3.1 Historical Topographic Maps, Aerial Photographs, and Sanborn Maps

Readily available historical USGS topographic maps, selected historical aerial photographs (at approximately 10-to-15-year intervals) and historical fire insurance maps produced by the Sanborn Map Company were reviewed to evaluate land development and obtain information concerning the history of development on and near the site. Reviewed historical topographic maps and aerial photographs are summarized below.

Historical fire insurance maps produced by the Sanborn Map Company were requested from EDR to evaluate past uses and relevant characteristics of the site and surrounding properties. Based upon inquiries to the above-listed Sanborn provider, Sanborn maps covering the site were not found.

Topographic maps:

o Sandusky, OH, dated 1904 (1:62,500) o Sandusky, OH, dated 1959, 1969, 1979, 2013, 2016, and 2019 (1:24,000)

Aerial photographs: 1937, 1960, 1969, 1977, 1983, 1988, 1995-1997, 2004, 2010, 2015, and 2019 (1” = 1,000’)

Table 6 - Historical Maps and Aerial Photographs

Direction Description

Site

Two small structures, presumably dwellings, in southeast corner of site, and ditches/drainageways traversing the central and east portions of the site (1904);

brush-covered and wooded land and agricultural fields (1937); the site area as being occupied by “Plum Brook Ordnance Works” with two buildings and a reservoir in the central portion of the site; several buildings and a railroad spur in the south portion of the site; a reservoir, small ponds, and small structures in the southeast portion of the site; railroad tracks, a railroad spur, and a small building in the west portion of the site; existing roadways; and intermittent drainageways and ditches, with the remainder of the site comprised of grass/brush-covered land and wooded land (1959-1960); the site area as being occupied by “National Aeronautics and Space Administration” (NASA), including the addition of several facilities buildings in the central portion of the site (associated with nuclear energy research and development), a nuclear reactor, a water tank, water tower, and an associated

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Direction Description parking lot; addition of two parking lots/exterior storage areas in the west portion of the site (1969-1997); railroad tracks /spurs as no longer being utilized/removed (2004); construction activities in central portion of site associated with decommissioning and demolition of nuclear reactor facilities and associated structures (2010); central buildings/structures as all being razed with the exception of existing Building 1121; marsh areas in central portion of site in area of former construction activities (2015); exterior storage areas and disturbed land in southeast portion of site, near reservoir and ponds (2019)

North

Two small structures, presumably dwellings (1904); several residential and farmstead properties and agricultural fields followed by West Bogart Road (1937);

majority of the residential and farmstead structures as being razed and active and fallow agricultural fields (1960); addition of several residential dwellings to the northeast (1969); additional residential dwellings (1977-1997); existing residential development (2004-2019)

East

One small structure, presumably and dwelling and Taylor Road (1904); agricultural fields followed by residential and farmstead properties (1937-1983); additional residential development (1988-1997); additional residential development and the remaining agricultural field as going fallow (2004-2015); existing residential development and grass-covered and wooded land (2019)

South

One small structure, presumably a dwelling and portions of intermittent drainageways (1904); existing Plum Brook substation and support building/powerhouse, existing Plum Brook warehouse building, grass/brush-covered land, roadways, exterior storage areas, and disturbed land areas (1960- 1995); construction of CCL control building (2004); existing buildings, exterior storage area, roadways, and grass/brush-covered land (2010-2019)

West Undeveloped land (1904); wooded land and agricultural fields (1937); wooded land, grass covered land, and several small buildings/trailers/exterior storage areas (1960); wooded, brush-covered, and grass-covered land (1969-2019)

Terracon reviewed the above historical sources for indications of RECs associated with the site. RECs associated with the site were not identified through a review of available topographic maps and aerial photographs. Copies of selected historical documents are included in Appendix C.

3.2 Historical City Directories

The Polk’s City Directory, Cole Information, and EDR Digital Archive city directories used in this study were made available through EDR (selected years reviewed: 1964 to 2020) and were reviewed at approximate five-year intervals, if readily available. Street listings were not available prior to 1992. The site has not been assigned a current street address.

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Table 7 - Historical City Directories

Direction Description

Site Current street address not assigned

North The site is currently, and has historically, been bordered to the north by residential development.

East The site is currently, and has historically, been bordered to the east by residential development.

South Current street address not assigned

West The site is currently, and has historically, been bordered to the west by undeveloped wooded and grass/brush-covered land.

Terracon reviewed the above historical city directories for indications of RECs associated with the site. RECs associated with the site were not identified through a review of available historical city directories. Copies of selected historical city directories are included in Appendix C.

3.3 Site Ownership

According to client provided documentation and information obtained from the Erie County Auditor’s website, the site is comprised of 870-acres situated in the north-central portion of a 6,436.5667-acre parent parcel of land identified as PPN: 32-60001.000 currently owned by United States of America NASA.

3.4 Title Search

Erie County Deed Records were reviewed by EDR of Shelton, Connecticut to obtain a chain-of-title for the site back to 1940. The title information is included in Appendix C.

Based on a review of the title provider’s research, the current site owner is listed as United States of America, as listed in the table below:

Table 8 – Chain-of-Title

Chain Transfer

Type Title Vested In

Title Received From Date

Executed

Warranty

Deed United States of America

Lawrence John Holkenborg and Nancy O. Holkenborg

April 5, 1971

Warranty

Deed United States of America

Paul B. Zorn and Florence G. Zorn

January 16, 3 Deed Lawrence John

Holkenburg and Nancy Frank J. Naderer and Mabel

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Chain Transfer

Type Title Vested In

Title Received From Date

Executed

Quit Claim

Deed Frank J. Naderer and

Mabel M. Naderer

United States of America, acting by and through the

Federal Farm Mortgage Company

June 6, 1950

Quit Claim

Deed Paul B. Zorn and Florence G. Zorn

United States of America, acting by and through the

Federal Farm Mortgage Company

May 2, 1950

Warranty

Deed United States of America

Lloyd A. Hills and Nellie Hills; Morris E. Hills and

Elsa M. Hills; Cora E.

Mefferd and Louis P.

Mefford; Clayton W. Hills and Frankie Hills

March 22, Warranty

Deed United States of America Alphonse Fritz

March 10, Warranty

Deed United States of America

John J. Brogle and Doris I.

Brogle

March 3, 1941

Warranty

Deed United States of America

John Macblain and Josephine Macblain

March 3, 1941

Unknown/Not

Found John Macblain and Josephine Macblain

Unknown/Not…