1043-00002 · Ironhaven Data Centers LLC · Land Acquisition/Stonebridge

environmental-dd-memo-stonebridge.docx DOCUMENT Real Estate

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PRIVILEGED AND CONFIDENTIAL ATTORNEY WORK PRODUCT

MEMORANDUM

TO: Douglas Fairchild, Responsible Partner, Calderwood & Harkness LLP Cynthia Ho, Lead Associate, Calderwood & Harkness LLP

FROM: Grace Nakamura, Working Associate, Calderwood & Harkness LLP

DATE: Draft — to be updated upon completion of Phase II ESA; initial draft circulated June 2025

RE: Environmental Due Diligence Summary — Stonebridge Parcel (62.0 acres), Loudoun County, Virginia (Loudoun County Tax Map Ref. /95-4A-1///)

Matter No.: 1043-00002

CLIENT: Ironhaven Data Centers LLC

This memorandum is a confidential attorney-client communication and attorney work product prepared in connection with the legal representation of Ironhaven Data Centers LLC. This memorandum is protected from disclosure by the attorney-client privilege, the work product doctrine, and other applicable privileges and protections. It should not be disclosed to any person outside of the attorney-client relationship without the prior written consent of Calderwood & Harkness LLP.

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I. EXECUTIVE SUMMARY

This memorandum summarizes the findings of the Phase I Environmental Site Assessment ("Phase I ESA") and the scope, status, and preliminary considerations arising from the Phase II Environmental Site Assessment ("Phase II ESA") conducted on the 62.0-acre parcel commonly known as the Stonebridge Parcel (the "Property" or "Stonebridge Parcel"), located at the northeast corner of Belmont Ridge Road and Stonebridge Boulevard, Ashburn, Virginia 20148 (Loudoun County Tax Map Ref. /95-4A-1///). The environmental assessments are being conducted in connection with the proposed acquisition of the Property by Ironhaven Data Centers LLC ("IHDC" or the "Client") from Blackthorn Realty Group, Inc. ("Blackthorn" or the "Seller") pursuant to that certain Purchase and Sale Agreement dated April 15, 2025 (the "Stonebridge PSA"), at a purchase price of $58,500,000. The Property is to be developed as the Stonebridge Data Center Campus, which has a total project budget of approximately $600,000,000 and a planned critical IT load of 96 megawatts.

The environmental assessments are being performed by Pendleton Environmental Associates, Inc. ("Pendleton"), a Virginia corporation specializing in environmental consulting and remediation services, under the direction of Dr. Renata Volkov, Lead Environmental Scientist. The Phase I ESA was conducted in conformity with ASTM E1527-21, and the Phase II ESA is being conducted in conformity with ASTM E1903-19. Both reports are intended to satisfy the "All Appropriate Inquiries" ("AAI") standard under the Comprehensive Environmental Response, Compensation, and Liability Act ("CERCLA") and the implementing regulations at 40 C.F.R. Part 312.

The Phase I ESA, with a target completion date of June 1, 2025, identified one Recognized Environmental Condition ("REC") related to the historical agricultural use of the Property. Specifically, the northwest quadrant of the Stonebridge Parcel, comprising approximately 4.2 acres, was identified as an area of concern due to the potential for residual pesticide contamination arising from historical orchard and row crop operations and the associated application of organochlorine and organophosphate pesticides. The presence of remnant agricultural building foundations in this area further raises concerns about potential historical storage and mixing of pesticides, herbicides, fertilizers, and fuels. No other RECs, Controlled Recognized Environmental Conditions ("CRECs"), or Historical Recognized Environmental Conditions ("HRECs") were identified on the Property.

Based on the identification of this REC, a Phase II ESA was authorized by IHDC and Calderwood & Harkness LLP ("C&H") to further characterize the nature and extent of potential contamination in the northwest quadrant through targeted soil and groundwater sampling. The Phase II ESA has a target completion date of July 1, 2025, which provides approximately thirteen calendar days of buffer before the expiration of the contractual due diligence period on July 14, 2025 (ninety days from the PSA execution date of April 15, 2025).

Subject to the final results of the Phase II ESA, the Stonebridge Parcel is expected to be suitable for the intended data center campus development. However, depending on the nature and extent of contamination identified in the northwest quadrant, remediation measures or institutional controls may be required. Preliminary Pendleton estimates for potential remediation costs range from $150,000 to $600,000, depending on the extent and depth of contamination encountered. The team should be prepared to evaluate remediation cost allocation strategies — including purchase price adjustment, project contingency budget, and potential seller indemnification — upon receipt of the Phase II final report. A contingency plan for extending the due diligence period has been prepared in the event that additional investigation time is required beyond the July 14, 2025 deadline.

II. BACKGROUND AND SCOPE OF ENGAGEMENT

A. Project Context

Ironhaven Data Centers LLC ("IHDC"), a Delaware limited liability company headquartered at 44680 Prentice Drive, Suite 200, Ashburn, Virginia 20147, is developing the Stonebridge Data Center Campus (the "Campus" or "Project") on an assembled site of approximately 81.4 acres in Loudoun County, Virginia. The assembled site consists of two parcels: the 62.0-acre Stonebridge Parcel, which is the subject of this memorandum, and the adjacent 19.4-acre Meridian Parcel, which is being acquired under a separate purchase and sale agreement and is the subject of a parallel environmental due diligence workstream.

IHDC is a portfolio company of Ridgeline Capital Partners Fund IV, LP, a private equity fund focused on digital infrastructure investments. IHDC's management team includes Marcus Thorne (Chief Executive Officer), Priya Dasgupta (Chief Financial Officer), and Leonard Castellano (Executive Vice President of Development). Mr. Castellano serves as the primary day-to-day contact for the development team and has been instrumental in coordinating the environmental due diligence process with Calderwood & Harkness LLP and Pendleton Environmental Associates.

The Stonebridge Parcel is being acquired from Blackthorn Realty Group, Inc., a Virginia corporation controlled by the Whitaker family. The principal officers and agents of Blackthorn relevant to this transaction are Donald R. Whitaker, President, and Patricia Whitaker-Connolly, General Counsel. Blackthorn's offices are located at 112 East Market Street, Suite 400, Leesburg, Virginia 20176. Blackthorn is represented in the transaction by Whitfield, Poole & Stratton LLP ("WPS"), with Harrison Poole serving as Lead Partner.

The purchase price for the Stonebridge Parcel is $58,500,000, which equates to approximately $943,548 per acre. Pursuant to the Stonebridge PSA, IHDC has deposited earnest money totaling $2,925,000 (five percent of the purchase price), which is divided into two equal tranches of $1,462,500 each. The first tranche was deposited upon execution of the PSA, and the second tranche becomes due upon the expiration of the due diligence period. The financial exposure associated with the second tranche of earnest money is a significant consideration in the due diligence timeline, as discussed further in Section V of this memorandum.

The Stonebridge Parcel is currently zoned PD-IP (Planned Development – Industrial Park) under the Loudoun County Revised 1993 Zoning Ordinance, as amended. A Zoning Modification ("ZMOD") application is required to permit data center use on the Property. The ZMOD application is expected to be assigned Docket No. ZMOD-2025-0038, with a filing target date of May 30, 2025. The entitlements process is being managed by Ashcroft & Wynn, P.C. (Thomas Ashcroft, lead counsel for land use matters) and Cornerstone Land Use Consulting, LLC (Alan Mercer, land use consultant).

B. Engagement of Pendleton Environmental Associates, Inc.

Calderwood & Harkness LLP, on behalf of IHDC, retained Pendleton Environmental Associates, Inc. ("Pendleton") to conduct Phase I and Phase II Environmental Site Assessments on the Stonebridge Parcel. Pendleton is a Virginia corporation with offices in Fairfax, Virginia, and has extensive experience conducting environmental assessments for commercial and data center real estate transactions in the Northern Virginia market. The engagement is directed by Dr. Renata Volkov, Lead Environmental Scientist, who holds a Ph.D. in Environmental Geochemistry from the Virginia Polytechnic Institute and State University and possesses over fifteen years of experience in Phase I and Phase II ESA practice.

The Phase I ESA was conducted in accordance with ASTM E1527-21, Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process, which is the current standard recognized by the U.S. Environmental Protection Agency ("EPA") for purposes of satisfying the AAI rule. The Phase II ESA is being conducted in accordance with ASTM E1903-19, Standard Practice for Environmental Site Assessments: Phase II Environmental Site Assessment Process, which provides guidance for the collection and analysis of soil, groundwater, and other environmental media to evaluate RECs identified during the Phase I ESA.

The ESA reports are specifically intended to satisfy the "All Appropriate Inquiries" ("AAI") standard under CERCLA, 42 U.S.C. § 9601 et seq., as implemented by the EPA's AAI Final Rule at 40 C.F.R. Part 312. Compliance with the AAI standard is a prerequisite for IHDC to avail itself of the liability protections available under CERCLA for innocent landowners (42 U.S.C. § 9601(35)(A)(i)), contiguous property owners (42 U.S.C. § 9607(q)), and bona fide prospective purchasers (42 U.S.C. § 9607(r)). Given the agricultural history of the Property and the identification of a REC, adherence to the AAI standard is of particular importance to preserving these defenses.

In addition to their legal significance under CERCLA, the Phase I and Phase II ESA reports are required by the construction lender syndicate as a condition precedent to funding under the $390,000,000 senior secured construction loan facility for the Project. The construction loan syndicate is composed of Summit National Bank, N.A. (as Administrative Agent), Cascade Commercial Lending Corp., and Harborview Trust Company. The lender syndicate's counsel is Redmond & Calloway LLP, led by Victor Redmond. Satisfactory environmental due diligence is a stated condition to loan closing, which is currently targeted for October 15, 2025. Any material environmental findings arising from the Phase II ESA could impact the lender syndicate's willingness to fund or could result in additional conditions being imposed on the loan.

C. Due Diligence Timeline

The following timeline summarizes the key dates governing the environmental due diligence process for the Stonebridge Parcel:

It is important to note that the Phase II ESA target completion date of July 1, 2025 affords only approximately thirteen calendar days of buffer before the due diligence period expires on July 14, 2025. In the event that the Phase II results are delayed, inconclusive, or require expanded investigation, IHDC may need to exercise its right to terminate the PSA during the due diligence period or negotiate a due diligence extension with Blackthorn. As a precautionary measure, a First Amendment to Stonebridge PSA (Due Diligence Extension) has been drafted and is available for execution if circumstances warrant. The potential need for an extension should be communicated proactively to WPS and Blackthorn.

III. PHASE I ENVIRONMENTAL SITE ASSESSMENT — FINDINGS

A. Site Description and Historical Use

The Stonebridge Parcel comprises approximately 62.0 acres of currently undeveloped and fallow land located at the northeast corner of Belmont Ridge Road (Route 659) and Stonebridge Boulevard, in unincorporated Loudoun County, Virginia 20148. The Property is identified in the Loudoun County land records by Tax Map Reference /95-4A-1///. The surrounding area is characterized by a mix of data center developments, commercial office parks, and remaining agricultural parcels transitioning to suburban and technology-oriented land uses — a pattern typical of the rapidly developing Ashburn technology corridor.

The topography of the Property is generally flat to gently rolling, consistent with the Piedmont physiographic province of northern Virginia. Surface drainage flows generally to the northeast, toward a tributary of Broad Run. The Property is bounded to the west by Belmont Ridge Road, to the south by Stonebridge Boulevard, to the east by undeveloped land and an existing data center campus operated by a third party, and to the north by a mix of agricultural parcels and scattered residential properties.

Current improvements on the Property are minimal and consist primarily of remnants of agricultural structures — including barns, storage buildings, and associated foundations — concentrated in the northwest portion of the parcel. These structures are in a state of disrepair and are scheduled for demolition as part of the site preparation and grading phase of the Project.

Pendleton's historical use analysis, based on a review of historical aerial photographs (dating from 1937 to present), United States Department of Agriculture ("USDA") records, Trelwick Fire Insurance Maps (where available for adjacent developed areas), and Loudoun County land records, established that the Stonebridge Parcel was used continuously for agricultural purposes from at least the 1930s through approximately the early 2000s. Agricultural activities on the Property included both row crop cultivation and orchard operations. Since the cessation of active agricultural use in the early 2000s, the Property has remained fallow and undeveloped, transitioning to grassland and ruderal vegetation typical of abandoned farmland in the Piedmont region.

Of particular significance to the environmental assessment, the northwest quadrant of the Property — an area comprising approximately 4.2 acres — was identified as having been used more intensively for orchard and row crop operations over a multi-decade period. Historical aerial photographs from the 1940s through the 1980s show an established orchard in this area, and interviews with the property owners (discussed further in Section III.D below) confirmed that organochlorine and organophosphate pesticides were applied in connection with these orchard operations. The concentration of agricultural structures (barns and storage buildings) in the northwest quadrant further suggests that this area served as the operational hub of the farming enterprise, where pesticides, herbicides, fertilizers, and fuel were stored, mixed, and loaded for application.

B. Records Review

Pendleton conducted a comprehensive federal, state, tribal, and local environmental records review using a standard ASTM-radius database search provided by Penrose Solutions ("EDR"). The database search included, but was not limited to, the following federal and state lists and databases:

• National Priorities List (NPL): No listings for the subject Property or within the standard ASTM search radius (1.0 mile).

• CERCLIS / SEMS: No listings for the subject Property or within the standard ASTM search radius (0.5 mile).

• RCRA CORRACTS / TSD Facilities: No listings for the subject Property or within the standard ASTM search radius (1.0 mile).

• RCRA Large Quantity Generators (LQG) / Small Quantity Generators (SQG): No listings for the subject Property or within the standard ASTM search radius (0.25 mile for SQG; 0.25 mile for LQG).

• Virginia DEQ Voluntary Remediation Program (VRP) Sites: No listings for the subject Property.

• Virginia Petroleum Storage Tank Database (UST/AST): No underground storage tanks or aboveground storage tanks registered or historically recorded for the subject Property.

• Virginia DEQ Solid Waste Management Facilities: No listings for the subject Property or within the standard search radius.

• Virginia DEQ Brownfields Inventory: No listings for the subject Property.

• Emergency Response Notification System (ERNS): No reported releases at the subject Property.

• State equivalent databases (Virginia DEQ lists): No listings for the subject Property on any applicable state-maintained environmental databases.

The adjacent property review, conducted within the standard ASTM search radii for each database category, did not identify any sites of concern that would pose a vapor intrusion risk or migrating contamination risk to the Stonebridge Parcel. While several data center and commercial properties were listed in the databases (primarily as SQGs for emergency generator fuel and battery maintenance), none of these listings indicated releases or conditions that would affect the subject Property based on distance, hydrogeological conditions, and the nature of the listed activities.

No underground storage tanks ("USTs") are registered or historically recorded on the Property in the Virginia DEQ petroleum storage tank database. No evidence of USTs was observed during the site reconnaissance.

No evidence was identified in the records review to suggest that hazardous waste disposal, landfilling, or industrial operations ever occurred on the Property. The historical use has been consistently agricultural throughout the period of record.

A review of Loudoun County property records, conducted by both Pendleton and separately by C&H's title team in coordination with Fidelitas Title & Escrow, Inc., confirmed that no environmental liens or activity and use limitations ("AULs") have been recorded against the Stonebridge Parcel. No deed restrictions, use limitations, or environmental covenants of any kind were identified in the chain of title.

C. Site Reconnaissance

A site reconnaissance of the entire 62.0-acre Stonebridge Parcel was conducted by Dr. Renata Volkov and Pendleton field staff on a date in May 2025, in accordance with ASTM E1527-21 requirements. Weather conditions at the time of the inspection were clear and dry, and the site was fully accessible.

The site reconnaissance confirmed that the Property is currently fallow agricultural land, consisting primarily of grassland and ruderal vegetation. Remnant orchard trees, including mature Tidewater Industries and peach trees, were observed in the northwest portion of the Property, consistent with the historical aerial photograph analysis indicating prior orchard use in this area. The remainder of the Property consists of open, formerly cultivated fields that have transitioned to a mix of native and non-native grass species.

Dr. Volkov's team conducted a systematic visual survey of the Property, with particular attention to indicators of potential environmental contamination, including the following:

• Drums, Chemical Containers, and Waste Materials: No drums, chemical containers, waste piles, or other evidence of chemical storage or disposal were observed on the Property.

• Staining, discoloration, or Distressed Vegetation: No soil staining, discoloration, or stressed vegetation patterns (beyond normal fallow conditions) were observed that would suggest releases of hazardous substances or petroleum products.

• Odors: No unusual odors were detected during the site inspection.

• Surface Water and Drainage: No sheen, discoloration, or other evidence of contamination was observed in surface water features or drainage channels on the Property.

• Agricultural Structures: Former agricultural building foundations were observed in the northwest quadrant of the Property. These foundations are associated with barns and storage buildings that appear to have been partially demolished or allowed to deteriorate over time. The foundations are constructed of poured concrete and stone, and some remnant structural elements (walls, framing) remain. The condition and location of these structures are consistent with historical use for agricultural equipment and chemical storage, and Pendleton identified this area as a focus of potential concern.

• Underground Storage Tanks: No evidence of USTs, including vent pipes, fill ports, or dispensers, was observed during the site reconnaissance.

• Wetlands: No wetlands were observed to encroach into the areas designated for planned building pads. However, a formal wetlands delineation is being conducted separately by Lumen Ridge Engineering, PLLC as part of the civil site design scope, and the results of that delineation should be reviewed for consistency with the environmental assessment findings.

Overall, the site reconnaissance did not reveal any evidence of environmental contamination beyond the conditions associated with the historical agricultural use in the northwest quadrant. The remainder of the Property presented no visual indicators of environmental concern.

D. Interviews. Pendleton conducted interviews with the following individuals as part of the Phase I ESA:

Donald R. Whitaker (President, Blackthorn Realty Group, Inc.) and Patricia Whitaker-Connolly (General Counsel, Blackthorn Realty Group, Inc.): Mr. Whitaker and Ms. Whitaker-Connolly were interviewed jointly by Dr. Volkov. Mr. Whitaker confirmed that the Whitaker family has owned portions of the Stonebridge Parcel since the 1960s, and that the Property was used for row crop and orchard farming operations continuously from that time through approximately the early 2000s. When asked about the types of agricultural chemicals used on the Property, Mr. Whitaker indicated that organochlorine and organophosphate pesticides were historically used in the orchard operations, particularly during the 1960s, 1970s, and 1980s, prior to the phase-out of many such chemicals by the EPA. Mr. Whitaker identified the northwest quadrant as the primary area of orchard operations and confirmed that the agricultural structures in that area were used for storage of pesticides, herbicides, fertilizers, and farm equipment. Mr. Whitaker stated that he was not aware of any spills, releases, or incidents involving hazardous substances on the Property, and that the Property has not been the subject of any regulatory investigations, enforcement actions, or voluntary cleanup activities. Ms. Whitaker-Connolly confirmed that Blackthorn's records do not reflect any environmental complaints, notices of violation, or regulatory correspondence related to the Property.

Loudoun County representatives: Pendleton contacted the Loudoun County Department of Building and Development and the Loudoun County Health Department to inquire about any enforcement actions, notices of violation, complaints, or other records associated with the Stonebridge Parcel. No responsive records were identified. The County representatives confirmed that no active permits, investigations, or complaints are on file for the Property.

E. Recognized Environmental Conditions (RECs) Identified

Based on the totality of the Phase I ESA findings — including the historical use analysis, records review, site reconnaissance, and interviews — Pendleton identified one Recognized Environmental Condition on the Stonebridge Parcel:

REC No. 1: Potential Residual Pesticide Contamination in the Northwest Quadrant. The northwest quadrant of the Stonebridge Parcel, comprising approximately 4.2 acres, constitutes a REC due to the historical use of this area for orchard and row crop operations involving the application of organochlorine and organophosphate pesticides over a multi-decade period (approximately 1930s through 1980s). The presence of former agricultural building foundations in this area raises additional concerns regarding historical pesticide, herbicide, fertilizer, and fuel storage and mixing activities. Organochlorine pesticides, including DDT (and its breakdown products DDE and DDD), chlordane, dieldrin, and endrin, are persistent organic pollutants that can remain in soil at elevated concentrations for decades following cessation of application. The potential for residual contamination at levels exceeding applicable screening criteria for industrial/commercial land use represents a condition indicative of a release or material threat of a release of hazardous substances into the subsurface.

No other RECs were identified on the Stonebridge Parcel. Additionally, no Controlled Recognized Environmental Conditions ("CRECs") or Historical Recognized Environmental Conditions ("HRECs") were identified. The absence of additional RECs is a favorable finding and indicates that, outside of the 4.2-acre northwest quadrant, the Property does not present environmental conditions that would be expected to impede the proposed development.

F. De Minimis Conditions and Other Findings

The Phase I ESA identified certain de minimis conditions and other findings that, while not rising to the level of RECs, warrant acknowledgment and, in some cases, management during the development of the Property:

Lead-Based Paint: The remnant agricultural structures in the northwest quadrant appear to contain lead-based paint, as indicated by the age and condition of the structures (pre-1978 construction). Lead-based paint on these structures will need to be addressed through appropriate abatement procedures during demolition. This work is expected to fall within the scope of the EPC Agreement with Titan-McAllister Construction Group, LLC and should be conducted in accordance with applicable federal, state, and local regulations, including EPA's Renovation, Repair, and Painting Rule (40 C.F.R. Part 745) and OSHA lead standards (29 C.F.R. § 1926.62).

Asbestos-Containing Materials: Older agricultural structures on the Property may contain asbestos-containing materials ("ACM"), particularly in roofing materials. A pre-demolition asbestos inspection should be conducted prior to any demolition activities. If ACM is identified, abatement must be performed by a licensed asbestos contractor in accordance with the National Emission Standards for Hazardous Air Pollutants ("NESHAP") regulations at 40 C.F.R. Part 61, Subpart M, and applicable Virginia regulations.

Radon: Loudoun County is classified by the EPA as a Zone 1 county, meaning that the predicted average indoor radon screening level exceeds 4 pCi/L (picocuries per liter), the EPA's recommended action level. However, the relevance of radon to the Stonebridge Data Center Campus is limited because data center buildings are typically unoccupied for purposes of radon exposure assessment. Radon testing may be recommended for any occupied office or administrative spaces planned as part of the Campus, but radon is not expected to be a material concern for the primary data center buildings.

The remainder of the 62.0-acre Stonebridge Parcel — approximately 57.8 acres — does not exhibit evidence of RECs, CRECs, or HRECs. This is a significant finding that supports the overall suitability of the Property for the intended data center development, subject to the resolution of the pesticide contamination concern in the northwest quadrant.

G. Phase I Conclusions and Recommendations

Based on the Phase I ESA findings, Pendleton recommended that a Phase II ESA be conducted to investigate the REC identified in the northwest quadrant. The Phase II ESA is focused on characterizing the nature, concentration, and extent of potential pesticide contamination in the soil and groundwater of the 4.2-acre area through a targeted sampling program. The Phase II investigation is necessary to determine whether contamination exists at concentrations exceeding applicable regulatory screening levels for industrial/commercial land use and, if so, to inform the development of an appropriate remediation or risk management strategy.

Upon receipt of the Phase I ESA report, IHDC (through Leonard Castellano, EVP of Development) and C&H authorized the Phase II ESA to proceed immediately in order to maintain compliance with the due diligence timeline under the Stonebridge PSA. Pendleton mobilized its field team promptly to commence the Phase II investigation.

IV. PHASE II ENVIRONMENTAL SITE ASSESSMENT — SCOPE AND PRELIMINARY FINDINGS

A. Scope of Phase II Investigation

The Phase II ESA is a targeted investigation focused exclusively on the northwest quadrant of the Stonebridge Parcel (approximately 4.2 acres), the area identified as a REC in the Phase I ESA. The investigation is designed to characterize the nature and extent of potential residual pesticide contamination in the soil and groundwater at this location. The scope of the Phase II ESA was developed by Pendleton in consultation with C&H and IHDC and includes the following primary components:

Soil Sampling: Pendleton has designed a grid-based soil boring program within the 4.2-acre investigation area. The number of soil borings will be confirmed in Pendleton's final Phase II workplan, but the preliminary sampling design calls for borings placed at regular grid intervals across the investigation area, with additional borings located at and near the former agricultural building foundations where pesticide storage and mixing is suspected to have occurred. Soil samples are being collected at multiple depth intervals — specifically at 0–2 feet below ground surface ("bgs"), 2–4 feet bgs, and 4–8 feet bgs — to evaluate the vertical distribution of potential contamination. The shallow sampling interval (0–2 feet bgs) is intended to capture surface soil conditions where pesticide residues from application would be most concentrated. The deeper intervals (2–4 feet and 4–8 feet bgs) are intended to assess whether contaminants have migrated downward through the soil profile toward the water table.

Groundwater Sampling: Pendleton is installing a network of temporary monitoring wells within and downgradient of the investigation area to assess whether pesticide contamination has migrated from soil to the shallow groundwater aquifer. Groundwater samples will be collected and analyzed for the same suite of analytes as the soil samples. The monitoring well locations have been selected based on anticipated groundwater flow direction (generally to the northeast, toward Broad Run) and the location of the areas of highest suspected contamination.

Analytes: The analytical suite for the Phase II ESA includes the following compound classes and individual parameters:

• Organochlorine Pesticides: DDT and its metabolites (DDE and DDD), chlordane (alpha and gamma isomers), dieldrin, aldrin, endrin, endosulfan, heptachlor, heptachlor epoxide, lindane (gamma-BHC), methoxychlor, and toxaphene.

• Organophosphate Pesticides: A standard suite of organophosphate compounds, including but not limited to chlorpyrifos, diazinon, malathion, and parathion.

• Herbicides: Select chlorophenoxy acid herbicides and other herbicide compounds historically used in agricultural operations.

• Metals: Arsenic and lead, both of which are commonly associated with historical pesticide formulations (e.g., lead arsenate) and may be present at elevated concentrations in former orchard soils.

• Volatile Organic Compounds (VOCs): A standard VOC screening suite is included as a precautionary measure to evaluate whether any petroleum or solvent contamination may be present in the vicinity of the former agricultural structures, notwithstanding the absence of USTs or other petroleum indicators.

Laboratory Analysis: All samples are being analyzed by a laboratory certified by the Virginia Division of Consolidated Laboratory Services (Virginia DEQ-certified laboratory). Analytical methods will follow EPA-approved methodologies, including EPA Method 8081B (organochlorine pesticides), EPA Method 8141B (organophosphate pesticides), EPA Method 8151A (herbicides), EPA Method 6010D/7471B (metals), and EPA Method 8260D (VOCs). Reporting limits have been established at levels at or below the applicable Virginia Voluntary Remediation Program ("VRP") Tier I screening levels for industrial/commercial land use and EPA Regional Screening Levels ("RSLs") for industrial/commercial soil and tapwater, to ensure that the analytical data are sufficient to support a risk-based evaluation of site conditions.

B. Status of Phase II ESA

Phase II ESA field work commenced in June 2025. Dr. Volkov and the Pendleton field team mobilized to the site to perform the soil boring program and install temporary monitoring wells. The Phase II ESA target completion date remains July 1, 2025.

As of the date of this memorandum, preliminary results from the Phase II ESA are pending. Laboratory analytical data from the initial rounds of soil and groundwater sampling have not yet been received. This memorandum will be updated and supplemented upon receipt of preliminary and final Phase II analytical results.

This section is reserved as a placeholder for the following information, which will be incorporated into the updated memorandum:

• Summary of soil sampling results, including concentrations of target analytes by boring location and depth interval, compared to applicable Virginia VRP Tier I screening levels and EPA RSLs.

• Summary of groundwater sampling results, including concentrations of target analytes by monitoring well location, compared to applicable groundwater screening criteria.

• Spatial and vertical delineation of any contamination identified, including the areal extent and depth of exceedances.

• Assessment of whether identified contamination is consistent with historical pesticide application patterns or whether localized "hot spots" exist that may be associated with pesticide storage and mixing activities near the former agricultural structures.

C. Anticipated Outcomes and Risk Assessment (Preliminary)

While the Phase II ESA results are pending, it is possible to outline the range of anticipated outcomes and their implications for the Project based on Dr. Volkov's preliminary assessment and professional experience with similar agricultural sites in the Northern Virginia and Piedmont region:

Scenario 1 — Below Screening Levels: If concentrations of pesticides, metals, and other target analytes in soil and groundwater are below the applicable Virginia VRP Tier I screening levels for industrial/commercial land use, the REC identified in the Phase I ESA may be effectively downgraded, and no further investigation or remediation may be required for the intended data center use. In this scenario, Pendleton would issue a "No Further Action" recommendation in the Phase II report, subject to standard caveats, and the environmental due diligence would be considered satisfactorily completed. This is a reasonably plausible outcome for the portion of the investigation area that was used for general row crop agriculture, where pesticide application rates were typically lower than in orchard operations.

Scenario 2 — Localized Exceedances Requiring Remediation: If pesticide or metals concentrations exceed screening levels in localized areas — particularly near the former agricultural building foundations — remediation or risk management measures may be required. The following remediation options would be evaluated:

(a) Excavation and Off-Site Disposal: Removal of impacted soils to a depth and lateral extent sufficient to achieve compliance with screening levels, followed by transportation and disposal at a permitted landfill facility. This is typically the most straightforward remediation approach for localized, shallow soil contamination but may be costly if the volume of impacted soil is significant.

(b) Soil Capping or Engineering Controls: Installation of an impervious cap (e.g., asphalt, concrete, or engineered soil cover) beneath building pads or hardscape in the affected area to prevent exposure to contaminated soils. This approach may be particularly well-suited to the Stonebridge Parcel given that the 4.2-acre northwest quadrant is currently planned as a location for structured parking and stormwater management facilities, which would inherently provide an impervious cover.

(c) Institutional Controls: Recording an environmental covenant or other activity and use limitation ("AUL") against the property pursuant to the Virginia Uniform Environmental Covenants Act (Va. Code § 10.1-1238 et seq.) to restrict land use to industrial/commercial purposes and impose management requirements (e.g., soil management plan, groundwater use restrictions) to protect against exposure pathways.

(d) Virginia DEQ Voluntary Remediation Program Enrollment: If contamination is significant, IHDC may elect to enroll the northwest quadrant of the Property in the Virginia DEQ Voluntary Remediation Program ("VRP") established under Va. Code § 10.1-1429.1 et seq. The VRP provides a regulatory framework for investigation and remediation under DEQ oversight, culminating in the issuance of a "Certification of Satisfactory Completion of Remediation" that provides comfort to property owners, lenders, and future transferees regarding the adequacy of the remediation. VRP enrollment, however, involves registration fees, additional consulting costs, and a regulatory timeline that may extend beyond the current due diligence period.

Scenario 3 — Widespread Contamination Requiring Material Remediation: If pesticide or metals contamination is found to be widespread throughout the 4.2-acre northwest quadrant at depths and concentrations requiring extensive remediation, the costs, timeline, and regulatory complexity would increase significantly. While this scenario is considered less likely based on Pendleton's preliminary assessment, it cannot be ruled out until the Phase II analytical data are available.

Preliminary Cost Estimates: Pendleton has provided an initial order-of-magnitude estimate for potential remediation costs, which is subject to significant revision upon receipt of the Phase II results. The current estimated range is as follows:

• Lower End ($150,000): Reflects a scenario involving localized soil removal (e.g., 500–1,000 cubic yards) from a limited area near the former agricultural building foundations, with off-site disposal and minimal backfill and compaction. This scenario assumes no groundwater contamination requiring treatment.

• Upper End ($600,000): Reflects a more extensive remediation scenario involving broader soil removal across a significant portion of the 4.2-acre area, potential soil capping or engineering controls for areas not slated for excavation, groundwater monitoring well installation and sampling over a multi-year period, and potential VRP enrollment and associated regulatory compliance costs.

These estimates do not include legal fees, project management costs, or potential construction schedule impacts. The remediation cost estimate will be refined upon receipt of the Phase II analytical data and the development of a site-specific remediation work plan by Pendleton.

Site Plan Considerations: As noted above, the 4.2-acre northwest quadrant is currently planned as a location for structured parking and stormwater management facilities, rather than a primary building pad for data center structures. This is a favorable circumstance from an environmental management perspective, as it may facilitate the use of engineering controls (e.g., an impervious cap provided by the parking structure or stormwater basin liner) as a component of the remediation strategy, potentially reducing the need for more invasive and costly excavation and disposal. The site plan configuration should be coordinated with Lumen Ridge Engineering, PLLC (Carlos Esteban, PE) to optimize the alignment between the development plan and any environmental controls that may be required.

V. IMPLICATIONS FOR THE STONEBRIDGE PARCEL ACQUISITION

A. Due Diligence Timing

The timing of the Phase II ESA relative to the contractual due diligence period is a critical consideration. The Phase II ESA completion target of July 1, 2025, provides approximately thirteen calendar days of buffer before the due diligence period expires on July 14, 2025. While this buffer should be sufficient to allow the team to review the Phase II results, assess their implications, and make an informed decision regarding the acquisition, it leaves limited margin for delays or complications.

If the Phase II results are delayed beyond the July 1, 2025 target — due to laboratory turnaround times, adverse weather affecting field work, or other factors — or if the results indicate that additional investigation is necessary (e.g., expanded sampling to delineate the full extent of a contamination plume, additional groundwater monitoring rounds, or supplemental analysis of unexpected contaminants), the thirteen-day buffer may prove insufficient. In that event, IHDC will face a decision point: either (a) terminate the PSA and receive a return of the earnest money deposit before the due diligence period expires, or (b) negotiate an extension of the due diligence period with Blackthorn.

As a proactive measure, C&H has prepared a First Amendment to Stonebridge PSA (Due Diligence Extension), which would extend the due diligence period by an additional thirty days to August 13, 2025. Execution of this amendment requires the consent of Blackthorn. We recommend that Douglas Fairchild or Cynthia Ho coordinate with Harrison Poole at Whitfield, Poole & Stratton LLP to assess Blackthorn's willingness to grant an extension if it becomes necessary. Given Blackthorn's financial interest in completing the transaction, we anticipate that a reasonable extension request would likely be favorably received, although Blackthorn may seek concessions (e.g., release of additional earnest money or an increase in the purchase price) in exchange for the extension.

The team should also be aware that the second tranche of the earnest money deposit ($1,462,500) becomes non-refundable and is due upon expiration of the due diligence period. If the due diligence period expires without termination or extension, IHDC's total earnest money exposure will increase to $2,925,000. Priya Dasgupta (CFO) should be advised of this financial exposure and the circumstances under which it could be triggered.

B. Purchase Agreement Considerations

The Stonebridge PSA contains environmental representations and warranties by Blackthorn in the applicable section of the agreement. C&H should confirm that these representations adequately address the REC identified in the Phase I ESA. Specifically, the following matters should be evaluated:

• Whether Blackthorn's representations regarding the environmental condition of the Property are sufficiently broad to encompass the historical use of organochlorine and organophosphate pesticides and any resulting soil or groundwater contamination.

• Whether the representations include a disclosure schedule or exception for known environmental conditions, and whether the identified REC has been disclosed by Blackthorn in the disclosure schedules or seller's certificate.

• Whether the PSA provides for a post-closing environmental indemnity from Blackthorn with respect to pre-existing environmental conditions, and if so, whether the survival period, cap, and basket provisions of such indemnity are adequate given the potential remediation costs.

• Whether IHDC should negotiate a purchase price reduction to account for estimated remediation costs, particularly if the Phase II results indicate that material remediation is required. A purchase price reduction has the advantage of providing IHDC with immediate financial relief rather than relying on a contingent indemnity claim against Blackthorn post-closing.

The PSA permits IHDC to terminate the agreement and receive a return of the earnest money deposit at any time during the due diligence period if environmental conditions are unacceptable to Buyer. This termination right provides IHDC with significant leverage in negotiating remediation cost allocation and other environmental protections. However, the termination right expires at the end of the due diligence period, underscoring the importance of completing the Phase II ESA and reaching a resolution with Blackthorn before July 14, 2025.

C. Impact on Construction Loan and Lender Requirements

The construction lender syndicate — Summit National Bank, N.A. (Administrative Agent), Cascade Commercial Lending Corp., and Harborview Trust Company — will require delivery of satisfactory Phase I and Phase II ESA reports as conditions precedent to closing the $390,000,000 senior secured construction loan facility. The loan closing is currently targeted for October 15, 2025. Any material environmental findings in the Phase II ESA could affect the lender syndicate's underwriting and approval process.

The Environmental Indemnity Agreement to be executed by Stonebridge Campus Holdings LLC (the borrower entity) and Ironhaven Data Centers LLC (as guarantor) in favor of the lender syndicate will cover environmental liabilities associated with the campus parcels. The scope and terms of the Environmental Indemnity Agreement should be reviewed by C&H to ensure that IHDC's indemnification obligations are appropriately bounded and that any carve-outs for pre-existing conditions or seller-allocated environmental liabilities are preserved.

Lender's counsel, Redmond & Calloway LLP (Victor Redmond), should be kept apprised of the Phase II findings and any remediation requirements on a timely basis. It is our recommendation that a summary of the Phase I ESA findings be provided to the lender syndicate and lender's counsel as part of the due diligence reporting process, with the full Phase II ESA report to follow upon its completion. Proactive communication with the lender syndicate is advisable to avoid surprises that could delay the loan closing.

If enrollment in the Virginia DEQ Voluntary Remediation Program is ultimately required, or if an environmental covenant or other AUL must be recorded against the Property, the lender syndicate will likely require review and approval of any such instrument. Activity and use limitations recorded against the Property could affect the lender's assessment of its deed of trust collateral, and the lender may impose conditions regarding the form and substance of any environmental covenant. The interaction between the environmental covenant and the lender's title insurance policy should be carefully evaluated.

D. Impact on Title Insurance

Fidelitas Title & Escrow, Inc. ("Fidelitas") is serving as the title agent for the Stonebridge Parcel acquisition, with the owner's policy being underwritten by Sovereign Title Insurance Company. The title commitment for the Stonebridge Parcel, with an effective date of April 3, 2025, provides for an owner's policy in the amount of $58,500,000. A lender's title insurance policy in the amount of $390,000,000 will also be required by the construction lender syndicate.

If the Phase II ESA results lead to the recording of any environmental liens, environmental covenants, or other AULs against the Property, these instruments would constitute additional title exceptions that would need to be reflected in both the owner's and lender's title policies. C&H should coordinate with Fidelitas and Sovereign to ensure that: (a) any environmental covenants are properly reflected as exceptions in the title policies; (b) the title insurer does not take an overly broad exception that would undermine the coverage provided by the policies; and (c) any endorsements that may be available to insure over or limit the impact of environmental exceptions are obtained.

Given the lender's significant collateral interest in the Property, the form of any environmental covenant and its treatment in the lender's title policy should be coordinated among C&H, Redmond & Calloway LLP (lender's counsel), Fidelitas, and Sovereign prior to loan closing.

E. Impact on Entitlements / ZMOD

The ZMOD application for the Stonebridge Parcel (expected Docket No. ZMOD-2025-0038, filing target May 30, 2025) may need to address environmental conditions on the Property as part of the site plan narrative or supporting documentation submitted to Loudoun County. While the ZMOD process is primarily a zoning entitlement proceeding, Loudoun County staff and the Board of Supervisors may inquire about environmental conditions, particularly given the agricultural history of the Property and the potential for public scrutiny of a large-scale data center development.

C&H should coordinate with Ashcroft & Wynn, P.C. (Thomas Ashcroft, land use counsel) and Cornerstone Land Use Consulting, LLC (Alan Mercer, land use consultant) regarding any Loudoun County requirements for disclosure of environmental conditions in the ZMOD application package. The team should assess whether the ZMOD narrative should proactively acknowledge the environmental due diligence process and any remediation commitments, or whether it is preferable to address environmental matters only if raised by County staff during the review process.

The proffer statement for the ZMOD application, which is estimated at approximately $2,400,000 (based on a rate of $5.00 per square foot of approximately 480,000 square feet of gross floor area), may potentially include commitments related to environmental remediation or environmental stewardship. If the proffer statement includes environmental-related commitments, these should be carefully drafted to ensure consistency with the Phase II ESA findings and any remediation strategy that may be adopted. IHDC should avoid committing to remediation measures in the proffer statement that exceed what is required under applicable environmental regulations, as such commitments would become legally binding conditions of the zoning approval.

VI. COORDINATION WITH OTHER DUE DILIGENCE WORKSTREAMS

The environmental due diligence findings intersect with several other workstreams associated with the Stonebridge Data Center Campus development. Coordination among the various consultants, contractors, and professional advisors is essential to ensure that environmental considerations are properly integrated into the overall project plan.

A. Geotechnical Investigation

Brannigan Geotechnical Engineering, LLC ("Brannigan") is conducting geotechnical investigations on the Stonebridge Parcel for the purpose of foundation design and site preparation planning. The geotechnical borings are being performed across the entire 62.0-acre parcel, including the northwest quadrant. Neil Brannigan, PE, the firm's principal, should be asked to report any observations from the geotechnical borings in the northwest quadrant that may be relevant to the environmental assessment, including unusual soil odors, discoloration, staining, or the presence of debris that could indicate historical chemical storage or disposal. Similarly, the Pendleton team should be made aware of the geotechnical boring locations and logs to avoid unnecessary duplication of effort and to maximize the information gained from subsurface investigation activities on the Property. Coordination between Brannigan and Pendleton should be facilitated through IHDC's development team or C&H to ensure that data sharing occurs promptly and completely.

B. Civil / Site Design

Lumen Ridge Engineering, PLLC ("Lumen Ridge") is the civil and site design engineer for the Stonebridge Data Center Campus. Carlos Esteban, PE, is the project engineer. The site plan for the Campus should be reviewed and, if necessary, modified to accommodate any environmental controls that may be required in the northwest quadrant as a result of the Phase II ESA findings. Specifically, Lumen Ridge should be prepared to:

• Incorporate an impervious cap design (e.g., structured parking pad, stormwater basin liner, or hardscape) in the northwest quadrant area if a soil capping strategy is adopted as a remediation measure.

• Designate locations for permanent groundwater monitoring wells, if required, ensuring that these locations do not conflict with planned improvements, utilities, or grading plans.

• Address stormwater management considerations associated with any soil disturbance or remediation activities in the northwest quadrant, including erosion and sediment control during any excavation work.

• Coordinate the wetlands delineation (being conducted by Lumen Ridge under the civil scope) with the environmental assessment to confirm that any wetland areas near the northwest quadrant are properly buffered and protected during remediation activities.

C. EPC Contract

The Engineering, Procurement, and Construction ("EPC") Agreement with Titan-McAllister Construction Group, LLC ("Titan-McAllister") provides for a Guaranteed Maximum Price ("GMP") of $412,000,000 for the construction of the Stonebridge Data Center Campus. The EPC scope includes demolition of existing structures and site work.

Any environmental remediation required in the northwest quadrant should be carefully evaluated with respect to the EPC Agreement to determine whether it will be treated as: (a) a pre-construction activity to be performed directly by the owner (IHDC) prior to Titan-McAllister's mobilization to the affected area, or (b) a change order under the EPC Agreement, with the work performed by Titan-McAllister or a designated subcontractor under the GMP framework.

We recommend that any required remediation be designated as an owner-directed pre-construction activity performed prior to the commencement of EPC work in the northwest quadrant. This approach has several advantages: it avoids triggering the GMP change order mechanism and the associated markup and fee provisions in the EPC Agreement; it allows IHDC to retain direct control over the remediation contractor selection and scope; and it avoids potential disputes with Titan-McAllister regarding scope, schedule, and cost impacts associated with encountering environmental contamination during construction activities. IHDC's development team (Leonard Castellano) should be consulted regarding the feasibility of this approach from a construction scheduling perspective.

Additionally, the demolition of remnant agricultural structures in the northwest quadrant, which falls within the EPC scope, will need to address the lead-based paint and potential asbestos-containing materials identified in the Phase I ESA. Titan-McAllister's demolition subcontractor should be required to conduct a pre-demolition asbestos inspection and to implement appropriate abatement procedures for both lead-based paint and any ACM identified.

D. Insurance. The builder's risk insurance policy for the Project ($412,000,000 in coverage, through Great Basin Surety & Insurance Corp.) typically contains a pollution exclusion that would preclude coverage for losses arising from the discovery, removal, or remediation of environmental contamination on the Project site. Given the identification of a REC in the Phase I ESA and the pending Phase II investigation, it is prudent to evaluate whether supplemental environmental insurance coverage is warranted.

C&H should direct Northgate Insurance Brokerage, LLC (William Keane, lead broker) to evaluate the following insurance products:

• Contractor's Pollution Liability ("CPL") Policy: A CPL policy would provide coverage for third-party claims and cleanup costs arising from pollution conditions discovered or exacerbated during construction activities. This coverage may be particularly relevant if Titan-McAllister's construction work in or near the northwest quadrant disturbs contaminated soils and causes or exacerbates the migration of contaminants.

• Environmental Insurance (Pollution Legal Liability) Policy: A broader environmental insurance policy could provide coverage for pre-existing contamination conditions on the Property, including cleanup costs, third-party bodily injury and property damage claims, and business interruption losses associated with environmental contamination. The availability and cost of such coverage will depend on the Phase II ESA findings and the insurer's assessment of the environmental risk profile of the Property.

The insurance evaluation should be coordinated with the Phase II ESA results, as the underwriting for environmental insurance products will typically require review of the ESA reports and any remediation plans.

VII. PENDING ACTION ITEMS AND RECOMMENDATIONS

Based on the Phase I ESA findings and the pending Phase II ESA investigation, C&H recommends the following action items and next steps:

1. Await Phase II ESA Final Report. The Phase II ESA final report is targeted for receipt on or before July 1, 2025. Dr. Renata Volkov of Pendleton Environmental Associates is to deliver the final report directly to C&H and IHDC (Leonard Castellano). Upon receipt, C&H will review and analyze the findings and update this memorandum accordingly. Any preliminary results or interim communications from Pendleton should be forwarded to C&H immediately upon receipt.

2. Brief the Client. C&H should schedule a call or meeting with IHDC's management team — Marcus Thorne (CEO), Priya Dasgupta (CFO), and Leonard Castellano (EVP of Development) — to advise them of the Phase I ESA findings, the Phase II ESA status, and the range of potential outcomes and their implications for the acquisition, development budget, and construction timeline. This briefing should include a discussion of IHDC's risk tolerance with respect to environmental conditions and its preferred strategy for remediation cost allocation (e.g., purchase price adjustment, seller indemnity, or absorption within the project contingency budget).

3. Due Diligence Extension Contingency. The First Amendment to Stonebridge PSA (Due Diligence Extension) has been prepared and is available for execution in the event that the Phase II ESA results are delayed, inconclusive, or require additional investigation beyond the July 14, 2025 due diligence expiration date. If it becomes apparent that an extension may be needed, C&H should coordinate promptly with Harrison Poole at Whitfield, Poole & Stratton LLP (Blackthorn's counsel) to obtain Blackthorn's consent to the extension. Early engagement with WPS is recommended to preserve goodwill and maximize the likelihood of a cooperative outcome.

4. Lender Communication. C&H should provide a summary of the Phase I ESA findings to the construction lender syndicate — Summit National Bank, N.A. (Karen Ellsworth, relationship manager), Cascade Commercial Lending Corp. (David Rennick), and Harborview Trust Company (Susan Applegategate) — and to lender's counsel, Redmond & Calloway LLP (Victor Redmond), as part of the ongoing due diligence reporting process. The full Phase II ESA report should be delivered to the lender syndicate and lender's counsel promptly upon its completion. Proactive and transparent communication with the lenders is essential to maintaining their confidence in the Project and avoiding delays to the October 15, 2025 loan closing target.

5. Remediation Cost Analysis. Upon receipt of the Phase II ESA results, C&H should coordinate with Pendleton to develop a detailed, site-specific remediation cost estimate. This estimate should be compared against the available budget allocations within the Project budget, including the $14,200,000 entitlements and soft costs line item and the $34,900,000 contingency and reserves line item, to assess the financial impact of remediation. The team should also evaluate the feasibility of allocating remediation costs to Blackthorn through a purchase price adjustment, seller-funded remediation, or post-closing environmental indemnity. The appropriate allocation strategy will depend on the magnitude of the remediation costs, IHDC's negotiating leverage, and Blackthorn's willingness to participate in the cost.

6. Environmental Insurance. C&H should direct Northgate Insurance Brokerage, LLC (Willi

PRIVILEGED AND CONFIDENTIAL ATTORNEY WORK PRODUCT
MEMORANDUM
TO: Douglas Fairchild, Responsible Partner, Calderwood & Harkness LLP Cynthia Ho, Lead Associate, Calderwood & Harkness LLP
FROM: Grace Nakamura, Working Associate, Calderwood & Harkness LLP
DATE: Draft — to be updated upon completion of Phase II ESA; initial draft circulated June 2025
RE: Environmental Due Diligence Summary — Stonebridge Parcel (62.0 acres), Loudoun County, Virginia (Loudoun County Tax Map Ref. /95-4A-1///)
Matter No.: 1043-00002
CLIENT: Ironhaven Data Centers LLC
This memorandum is a confidential attorney-client communication and attorney work product prepared in connection with the legal representation of Ironhaven Data Centers LLC. This memorandum is protected from disclosure by the attorney-client privilege, the work product doctrine, and other applicable privileges and protections. It should not be disclosed to any person outside of the attorney-client relationship without the prior written consent of Calderwood & Harkness LLP.
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I. EXECUTIVE SUMMARY
This memorandum summarizes the findings of the Phase I Environmental Site Assessment ("Phase I ESA") and the scope, status, and preliminary considerations arising from the Phase II Environmental Site Assessment ("Phase II ESA") conducted on the 62.0-acre parcel commonly known as the Stonebridge Parcel (the "Property" or "Stonebridge Parcel"), located at the northeast corner of Belmont Ridge Road and Stonebridge Boulevard, Ashburn, Virginia 20148 (Loudoun County Tax Map Ref. /95-4A-1///). The environmental assessments are being conducted in connection with the proposed acquisition of the Property by Ironhaven Data Centers LLC ("IHDC" or the "Client") from Blackthorn Realty Group, Inc. ("Blackthorn" or the "Seller") pursuant to that certain Purchase and Sale Agreement dated April 15, 2025 (the "Stonebridge PSA"), at a purchase price of $58,500,000. The Property is to be developed as the Stonebridge Data Center Campus, which has a total project budget of approximately $600,000,000 and a planned critical IT load of 96 megawatts.
The environmental assessments are being performed by Pendleton Environmental Associates, Inc. ("Pendleton"), a Virginia corporation specializing in environmental consulting and remediation services, under the direction of Dr. Renata Volkov, Lead Environmental Scientist. The Phase I ESA was conducted in conformity with ASTM E1527-21, and the Phase II ESA is being conducted in conformity with ASTM E1903-19. Both reports are intended to satisfy the "All Appropriate Inquiries" ("AAI") standard under the Comprehensive Environmental Response, Compensation, and Liability Act ("CERCLA") and the implementing regulations at 40 C.F.R. Part 312.
The Phase I ESA, with a target completion date of June 1, 2025, identified one Recognized Environmental Condition ("REC") related to the historical agricultural use of the Property. Specifically, the northwest quadrant of the Stonebridge Parcel, comprising approximately 4.2 acres, was identified as an area of concern due to the potential for residual pesticide contamination arising from historical orchard and row crop operations and the associated application of organochlorine and organophosphate pesticides. The presence of remnant agricultural building foundations in this area further raises concerns about potential historical storage and mixing of pesticides, herbicides, fertilizers, and fuels. No other RECs, Controlled Recognized Environmental Conditions ("CRECs"), or Historical Recognized Environmental Conditions ("HRECs") were identified on the Property.
Based on the identification of this REC, a Phase II ESA was authorized by IHDC and Calderwood & Harkness LLP ("C&H") to further characterize the nature and extent of potential contamination in the northwest quadrant through targeted soil and groundwater sampling. The Phase II ESA has a target completion date of July 1, 2025, which provides approximately thirteen calendar days of buffer before the expiration of the contractual due diligence period on July 14, 2025 (ninety days from the PSA execution date of April 15, 2025).
Subject to the final results of the Phase II ESA, the Stonebridge Parcel is expected to be suitable for the intended data center campus development. However, depending on the nature and extent of contamination identified in the northwest quadrant, remediation measures or institutional controls may be required. Preliminary Pendleton estimates for potential remediation costs range from $150,000 to $600,000, depending on the extent and depth of contamination encountered. The team should be prepared to evaluate remediation cost allocation strategies — including purchase price adjustment, project contingency budget, and potential seller indemnification — upon receipt of the Phase II final report. A contingency plan for extending the due diligence period has been prepared in the event that additional investigation time is required beyond the July 14, 2025 deadline.
II. BACKGROUND AND SCOPE OF ENGAGEMENT
A. Project Context
Ironhaven Data Centers LLC ("IHDC"), a Delaware limited liability company headquartered at 44680 Prentice Drive, Suite 200, Ashburn, Virginia 20147, is developing the Stonebridge Data Center Campus (the "Campus" or "Project") on an assembled site of approximately 81.4 acres in Loudoun County, Virginia. The assembled site consists of two parcels: the 62.0-acre Stonebridge Parcel, which is the subject of this memorandum, and the adjacent 19.4-acre Meridian Parcel, which is being acquired under a separate purchase and sale agreement and is the subject of a parallel environmental due diligence workstream.
IHDC is a portfolio company of Ridgeline Capital Partners Fund IV, LP, a private equity fund focused on digital infrastructure investments. IHDC's management team includes Marcus Thorne (Chief Executive Officer), Priya Dasgupta (Chief Financial Officer), and Leonard Castellano (Executive Vice President of Development). Mr. Castellano serves as the primary day-to-day contact for the development team and has been instrumental in coordinating the environmental due diligence process with Calderwood & Harkness LLP and Pendleton Environmental Associates.
The Stonebridge Parcel is being acquired from Blackthorn Realty Group, Inc., a Virginia corporation controlled by the Whitaker family. The principal officers and agents of Blackthorn relevant to this transaction are Donald R. Whitaker, President, and Patricia Whitaker-Connolly, General Counsel. Blackthorn's offices are located at 112 East Market Street, Suite 400, Leesburg, Virginia 20176. Blackthorn is represented in the transaction by Whitfield, Poole & Stratton LLP ("WPS"), with Harrison Poole serving as Lead Partner.
The purchase price for the Stonebridge Parcel is $58,500,000, which equates to approximately $943,548 per acre. Pursuant to the Stonebridge PSA, IHDC has deposited earnest money totaling $2,925,000 (five percent of the purchase price), which is divided into two equal tranches of $1,462,500 each. The first tranche was deposited upon execution of the PSA, and the second tranche becomes due upon the expiration of the due diligence period. The financial exposure associated with the second tranche of earnest money is a significant consideration in the due diligence timeline, as discussed further in Section V of this memorandum.
The Stonebridge Parcel is currently zoned PD-IP (Planned Development – Industrial Park) under the Loudoun County Revised 1993 Zoning Ordinance, as amended. A Zoning Modification ("ZMOD") application is required to permit data center use on the Property. The ZMOD application is expected to be assigned Docket No. ZMOD-2025-0038, with a filing target date of May 30, 2025. The entitlements process is being managed by Ashcroft & Wynn, P.C. (Thomas Ashcroft, lead counsel for land use matters) and Cornerstone Land Use Consulting, LLC (Alan Mercer, land use consultant).
B. Engagement of Pendleton Environmental Associates, Inc.
Calderwood & Harkness LLP, on behalf of IHDC, retained Pendleton Environmental Associates, Inc. ("Pendleton") to conduct Phase I and Phase II Environmental Site Assessments on the Stonebridge Parcel. Pendleton is a Virginia corporation with offices in Fairfax, Virginia, and has extensive experience conducting environmental assessments for commercial and data center real estate transactions in the Northern Virginia market. The engagement is directed by Dr. Renata Volkov, Lead Environmental Scientist, who holds a Ph.D. in Environmental Geochemistry from the Virginia Polytechnic Institute and State University and possesses over fifteen years of experience in Phase I and Phase II ESA practice.
The Phase I ESA was conducted in accordance with ASTM E1527-21, Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process, which is the current standard recognized by the U.S. Environmental Protection Agency ("EPA") for purposes of satisfying the AAI rule. The Phase II ESA is being conducted in accordance with ASTM E1903-19, Standard Practice for Environmental Site Assessments: Phase II Environmental Site Assessment Process, which provides guidance for the collection and analysis of soil, groundwater, and other environmental media to evaluate RECs identified during the Phase I ESA.
The ESA reports are specifically intended to satisfy the "All Appropriate Inquiries" ("AAI") standard under CERCLA, 42 U.S.C. § 9601 et seq., as implemented by the EPA's AAI Final Rule at 40 C.F.R. Part 312. Compliance with the AAI standard is a prerequisite for IHDC to avail itself of the liability protections available under CERCLA for innocent landowners (42 U.S.C. § 9601(35)(A)(i)), contiguous property owners (42 U.S.C. § 9607(q)), and bona fide prospective purchasers (42 U.S.C. § 9607(r)). Given the agricultural history of the Property and the identification of a REC, adherence to the AAI standard is of particular importance to preserving these defenses.
In addition to their legal significance under CERCLA, the Phase I and Phase II ESA reports are required by the construction lender syndicate as a condition precedent to funding under the $390,000,000 senior secured construction loan facility for the Project. The construction loan syndicate is composed of Summit National Bank, N.A. (as Administrative Agent), Cascade Commercial Lending Corp., and Harborview Trust Company. The lender syndicate's counsel is Redmond & Calloway LLP, led by Victor Redmond. Satisfactory environmental due diligence is a stated condition to loan closing, which is currently targeted for October 15, 2025. Any material environmental findings arising from the Phase II ESA could impact the lender syndicate's willingness to fund or could result in additional conditions being imposed on the loan.
C. Due Diligence Timeline
The following timeline summarizes the key dates governing the environmental due diligence process for the Stonebridge Parcel:
It is important to note that the Phase II ESA target completion date of July 1, 2025 affords only approximately thirteen calendar days of buffer before the due diligence period expires on July 14, 2025. In the event that the Phase II results are delayed, inconclusive, or require expanded investigation, IHDC may need to exercise its right to terminate the PSA during the due diligence period or negotiate a due diligence extension with Blackthorn. As a precautionary measure, a First Amendment to Stonebridge PSA (Due Diligence Extension) has been drafted and is available for execution if circumstances warrant. The potential need for an extension should be communicated proactively to WPS and Blackthorn.
III. PHASE I ENVIRONMENTAL SITE ASSESSMENT — FINDINGS
A. Site Description and Historical Use
The Stonebridge Parcel comprises approximately 62.0 acres of currently undeveloped and fallow land located at the northeast corner of Belmont Ridge Road (Route 659) and Stonebridge Boulevard, in unincorporated Loudoun County, Virginia 20148. The Property is identified in the Loudoun County land records by Tax Map Reference /95-4A-1///. The surrounding area is characterized by a mix of data center developments, commercial office parks, and remaining agricultural parcels transitioning to suburban and technology-oriented land uses — a pattern typical of the rapidly developing Ashburn technology corridor.
The topography of the Property is generally flat to gently rolling, consistent with the Piedmont physiographic province of northern Virginia. Surface drainage flows generally to the northeast, toward a tributary of Broad Run. The Property is bounded to the west by Belmont Ridge Road, to the south by Stonebridge Boulevard, to the east by undeveloped land and an existing data center campus operated by a third party, and to the north by a mix of agricultural parcels and scattered residential properties.
Current improvements on the Property are minimal and consist primarily of remnants of agricultural structures — including barns, storage buildings, and associated foundations — concentrated in the northwest portion of the parcel. These structures are in a state of disrepair and are scheduled for demolition as part of the site preparation and grading phase of the Project.
Pendleton's historical use analysis, based on a review of historical aerial photographs (dating from 1937 to present), United States Department of Agriculture ("USDA") records, Trelwick Fire Insurance Maps (where available for adjacent developed areas), and Loudoun County land records, established that the Stonebridge Parcel was used continuously for agricultural purposes from at least the 1930s through approximately the early 2000s. Agricultural activities on the Property included both row crop cultivation and orchard operations. Since the cessation of active agricultural use in the early 2000s, the Property has remained fallow and undeveloped, transitioning to grassland and ruderal vegetation typical of abandoned farmland in the Piedmont region.
Of particular significance to the environmental assessment, the northwest quadrant of the Property — an area comprising approximately 4.2 acres — was identified as having been used more intensively for orchard and row crop operations over a multi-decade period. Historical aerial photographs from the 1940s through the 1980s show an established orchard in this area, and interviews with the property owners (discussed further in Section III.D below) confirmed that organochlorine and organophosphate pesticides were applied in connection with these orchard operations. The concentration of agricultural structures (barns and storage buildings) in the northwest quadrant further suggests that this area served as the operational hub of the farming enterprise, where pesticides, herbicides, fertilizers, and fuel were stored, mixed, and loaded for application.
B. Records Review
Pendleton conducted a comprehensive federal, state, tribal, and local environmental records review using a standard ASTM-radius database search provided by Penrose Solutions ("EDR"). The database search included, but was not limited to, the following federal and state lists and databases:
• National Priorities List (NPL): No listings for the subject Property or within the standard ASTM search radius (1.0 mile).
• CERCLIS / SEMS: No listings for the subject Property or within the standard ASTM search radius (0.5 mile).
• RCRA CORRACTS / TSD Facilities: No listings for the subject Property or within the standard ASTM search radius (1.0 mile).
• RCRA Large Quantity Generators (LQG) / Small Quantity Generators (SQG): No listings for the subject Property or within the standard ASTM search radius (0.25 mile for SQG; 0.25 mile for LQG).
• Virginia DEQ Voluntary Remediation Program (VRP) Sites: No listings for the subject Property.
• Virginia Petroleum Storage Tank Database (UST/AST): No underground storage tanks or aboveground storage tanks registered or historically recorded for the subject Property.
• Virginia DEQ Solid Waste Management Facilities: No listings for the subject Property or within the standard search radius.
• Virginia DEQ Brownfields Inventory: No listings for the subject Property.
• Emergency Response Notification System (ERNS): No reported releases at the subject Property.
• State equivalent databases (Virginia DEQ lists): No listings for the subject Property on any applicable state-maintained environmental databases.
The adjacent property review, conducted within the standard ASTM search radii for each database category, did not identify any sites of concern that would pose a vapor intrusion risk or migrating contamination risk to the Stonebridge Parcel. While several data center and commercial properties were listed in the databases (primarily as SQGs for emergency generator fuel and battery maintenance), none of these listings indicated releases or conditions that would affect the subject Property based on distance, hydrogeological conditions, and the nature of the listed activities.
No underground storage tanks ("USTs") are registered or historically recorded on the Property in the Virginia DEQ petroleum storage tank database. No evidence of USTs was observed during the site reconnaissance.
No evidence was identified in the records review to suggest that hazardous waste disposal, landfilling, or industrial operations ever occurred on the Property. The historical use has been consistently agricultural throughout the period of record.
A review of Loudoun County property records, conducted by both Pendleton and separately by C&H's title team in coordination with Fidelitas Title & Escrow, Inc., confirmed that no environmental liens or activity and use limitations ("AULs") have been recorded against the Stonebridge Parcel. No deed restrictions, use limitations, or environmental covenants of any kind were identified in the chain of title.
C. Site Reconnaissance
A site reconnaissance of the entire 62.0-acre Stonebridge Parcel was conducted by Dr. Renata Volkov and Pendleton field staff on a date in May 2025, in accordance with ASTM E1527-21 requirements. Weather conditions at the time of the inspection were clear and dry, and the site was fully accessible.
The site reconnaissance confirmed that the Property is currently fallow agricultural land, consisting primarily of grassland and ruderal vegetation. Remnant orchard trees, including mature Tidewater Industries and peach trees, were observed in the northwest portion of the Property, consistent with the historical aerial photograph analysis indicating prior orchard use in this area. The remainder of the Property consists of open, formerly cultivated fields that have transitioned to a mix of native and non-native grass species.
Dr. Volkov's team conducted a systematic visual survey of the Property, with particular attention to indicators of potential environmental contamination, including the following:
• Drums, Chemical Containers, and Waste Materials: No drums, chemical containers, waste piles, or other evidence of chemical storage or disposal were observed on the Property.
• Staining, discoloration, or Distressed Vegetation: No soil staining, discoloration, or stressed vegetation patterns (beyond normal fallow conditions) were observed that would suggest releases of hazardous substances or petroleum products.
• Odors: No unusual odors were detected during the site inspection.
• Surface Water and Drainage: No sheen, discoloration, or other evidence of contamination was observed in surface water features or drainage channels on the Property.
• Agricultural Structures: Former agricultural building foundations were observed in the northwest quadrant of the Property. These foundations are associated with barns and storage buildings that appear to have been partially demolished or allowed to deteriorate over time. The foundations are constructed of poured concrete and stone, and some remnant structural elements (walls, framing) remain. The condition and location of these structures are consistent with historical use for agricultural equipment and chemical storage, and Pendleton identified this area as a focus of potential concern.
• Underground Storage Tanks: No evidence of USTs, including vent pipes, fill ports, or dispensers, was observed during the site reconnaissance.
• Wetlands: No wetlands were observed to encroach into the areas designated for planned building pads. However, a formal wetlands delineation is being conducted separately by Lumen Ridge Engineering, PLLC as part of the civil site design scope, and the results of that delineation should be reviewed for consistency with the environmental assessment findings.
Overall, the site reconnaissance did not reveal any evidence of environmental contamination beyond the conditions associated with the historical agricultural use in the northwest quadrant. The remainder of the Property presented no visual indicators of environmental concern.
D. Interviews. Pendleton conducted interviews with the following individuals as part of the Phase I ESA:
Donald R. Whitaker (President, Blackthorn Realty Group, Inc.) and Patricia Whitaker-Connolly (General Counsel, Blackthorn Realty Group, Inc.): Mr. Whitaker and Ms. Whitaker-Connolly were interviewed jointly by Dr. Volkov. Mr. Whitaker confirmed that the Whitaker family has owned portions of the Stonebridge Parcel since the 1960s, and that the Property was used for row crop and orchard farming operations continuously from that time through approximately the early 2000s. When asked about the types of agricultural chemicals used on the Property, Mr. Whitaker indicated that organochlorine and organophosphate pesticides were historically used in the orchard operations, particularly during the 1960s, 1970s, and 1980s, prior to the phase-out of many such chemicals by the EPA. Mr. Whitaker identified the northwest quadrant as the primary area of orchard operations and confirmed that the agricultural structures in that area were used for storage of pesticides, herbicides, fertilizers, and farm equipment. Mr. Whitaker stated that he was not aware of any spills, releases, or incidents involving hazardous substances on the Property, and that the Property has not been the subject of any regulatory investigations, enforcement actions, or voluntary cleanup activities. Ms. Whitaker-Connolly confirmed that Blackthorn's records do not reflect any environmental complaints, notices of violation, or regulatory correspondence related to the Property.
Loudoun County representatives: Pendleton contacted the Loudoun County Department of Building and Development and the Loudoun County Health Department to inquire about any enforcement actions, notices of violation, complaints, or other records associated with the Stonebridge Parcel. No responsive records were identified. The County representatives confirmed that no active permits, investigations, or complaints are on file for the Property.
E. Recognized Environmental Conditions (RECs) Identified
Based on the totality of the Phase I ESA findings — including the historical use analysis, records review, site reconnaissance, and interviews — Pendleton identified one Recognized Environmental Condition on the Stonebridge Parcel:
REC No. 1: Potential Residual Pesticide Contamination in the Northwest Quadrant. The northwest quadrant of the Stonebridge Parcel, comprising approximately 4.2 acres, constitutes a REC due to the historical use of this area for orchard and row crop operations involving the application of organochlorine and organophosphate pesticides over a multi-decade period (approximately 1930s through 1980s). The presence of former agricultural building foundations in this area raises additional concerns regarding historical pesticide, herbicide, fertilizer, and fuel storage and mixing activities. Organochlorine pesticides, including DDT (and its breakdown products DDE and DDD), chlordane, dieldrin, and endrin, are persistent organic pollutants that can remain in soil at elevated concentrations for decades following cessation of application. The potential for residual contamination at levels exceeding applicable screening criteria for industrial/commercial land use represents a condition indicative of a release or material threat of a release of hazardous substances into the subsurface.
No other RECs were identified on the Stonebridge Parcel. Additionally, no Controlled Recognized Environmental Conditions ("CRECs") or Historical Recognized Environmental Conditions ("HRECs") were identified. The absence of additional RECs is a favorable finding and indicates that, outside of the 4.2-acre northwest quadrant, the Property does not present environmental conditions that would be expected to impede the proposed development.
F. De Minimis Conditions and Other Findings
The Phase I ESA identified certain de minimis conditions and other findings that, while not rising to the level of RECs, warrant acknowledgment and, in some cases, management during the development of the Property:
Lead-Based Paint: The remnant agricultural structures in the northwest quadrant appear to contain lead-based paint, as indicated by the age and condition of the structures (pre-1978 construction). Lead-based paint on these structures will need to be addressed through appropriate abatement procedures during demolition. This work is expected to fall within the scope of the EPC Agreement with Titan-McAllister Construction Group, LLC and should be conducted in accordance with applicable federal, state, and local regulations, including EPA's Renovation, Repair, and Painting Rule (40 C.F.R. Part 745) and OSHA lead standards (29 C.F.R. § 1926.62).
Asbestos-Containing Materials: Older agricultural structures on the Property may contain asbestos-containing materials ("ACM"), particularly in roofing materials. A pre-demolition asbestos inspection should be conducted prior to any demolition activities. If ACM is identified, abatement must be performed by a licensed asbestos contractor in accordance with the National Emission Standards for Hazardous Air Pollutants ("NESHAP") regulations at 40 C.F.R. Part 61, Subpart M, and applicable Virginia regulations.
Radon: Loudoun County is classified by the EPA as a Zone 1 county, meaning that the predicted average indoor radon screening level exceeds 4 pCi/L (picocuries per liter), the EPA's recommended action level. However, the relevance of radon to the Stonebridge Data Center Campus is limited because data center buildings are typically unoccupied for purposes of radon exposure assessment. Radon testing may be recommended for any occupied office or administrative spaces planned as part of the Campus, but radon is not expected to be a material concern for the primary data center buildings.
The remainder of the 62.0-acre Stonebridge Parcel — approximately 57.8 acres — does not exhibit evidence of RECs, CRECs, or HRECs. This is a significant finding that supports the overall suitability of the Property for the intended data center development, subject to the resolution of the pesticide contamination concern in the northwest quadrant.
G. Phase I Conclusions and Recommendations
Based on the Phase I ESA findings, Pendleton recommended that a Phase II ESA be conducted to investigate the REC identified in the northwest quadrant. The Phase II ESA is focused on characterizing the nature, concentration, and extent of potential pesticide contamination in the soil and groundwater of the 4.2-acre area through a targeted sampling program. The Phase II investigation is necessary to determine whether contamination exists at concentrations exceeding applicable regulatory screening levels for industrial/commercial land use and, if so, to inform the development of an appropriate remediation or risk management strategy.
Upon receipt of the Phase I ESA report, IHDC (through Leonard Castellano, EVP of Development) and C&H authorized the Phase II ESA to proceed immediately in order to maintain compliance with the due diligence timeline under the Stonebridge PSA. Pendleton mobilized its field team promptly to commence the Phase II investigation.
IV. PHASE II ENVIRONMENTAL SITE ASSESSMENT — SCOPE AND PRELIMINARY FINDINGS
A. Scope of Phase II Investigation
The Phase II ESA is a targeted investigation focused exclusively on the northwest quadrant of the Stonebridge Parcel (approximately 4.2 acres), the area identified as a REC in the Phase I ESA. The investigation is designed to characterize the nature and extent of potential residual pesticide contamination in the soil and groundwater at this location. The scope of the Phase II ESA was developed by Pendleton in consultation with C&H and IHDC and includes the following primary components:
Soil Sampling: Pendleton has designed a grid-based soil boring program within the 4.2-acre investigation area. The number of soil borings will be confirmed in Pendleton's final Phase II workplan, but the preliminary sampling design calls for borings placed at regular grid intervals across the investigation area, with additional borings located at and near the former agricultural building foundations where pesticide storage and mixing is suspected to have occurred. Soil samples are being collected at multiple depth intervals — specifically at 0–2 feet below ground surface ("bgs"), 2–4 feet bgs, and 4–8 feet bgs — to evaluate the vertical distribution of potential contamination. The shallow sampling interval (0–2 feet bgs) is intended to capture surface soil conditions where pesticide residues from application would be most concentrated. The deeper intervals (2–4 feet and 4–8 feet bgs) are intended to assess whether contaminants have migrated downward through the soil profile toward the water table.
Groundwater Sampling: Pendleton is installing a network of temporary monitoring wells within and downgradient of the investigation area to assess whether pesticide contamination has migrated from soil to the shallow groundwater aquifer. Groundwater samples will be collected and analyzed for the same suite of analytes as the soil samples. The monitoring well locations have been selected based on anticipated groundwater flow direction (generally to the northeast, toward Broad Run) and the location of the areas of highest suspected contamination.
Analytes: The analytical suite for the Phase II ESA includes the following compound classes and individual parameters:
• Organochlorine Pesticides: DDT and its metabolites (DDE and DDD), chlordane (alpha and gamma isomers), dieldrin, aldrin, endrin, endosulfan, heptachlor, heptachlor epoxide, lindane (gamma-BHC), methoxychlor, and toxaphene.
• Organophosphate Pesticides: A standard suite of organophosphate compounds, including but not limited to chlorpyrifos, diazinon, malathion, and parathion.
• Herbicides: Select chlorophenoxy acid herbicides and other herbicide compounds historically used in agricultural operations.
• Metals: Arsenic and lead, both of which are commonly associated with historical pesticide formulations (e.g., lead arsenate) and may be present at elevated concentrations in former orchard soils.
• Volatile Organic Compounds (VOCs): A standard VOC screening suite is included as a precautionary measure to evaluate whether any petroleum or solvent contamination may be present in the vicinity of the former agricultural structures, notwithstanding the absence of USTs or other petroleum indicators.
Laboratory Analysis: All samples are being analyzed by a laboratory certified by the Virginia Division of Consolidated Laboratory Services (Virginia DEQ-certified laboratory). Analytical methods will follow EPA-approved methodologies, including EPA Method 8081B (organochlorine pesticides), EPA Method 8141B (organophosphate pesticides), EPA Method 8151A (herbicides), EPA Method 6010D/7471B (metals), and EPA Method 8260D (VOCs). Reporting limits have been established at levels at or below the applicable Virginia Voluntary Remediation Program ("VRP") Tier I screening levels for industrial/commercial land use and EPA Regional Screening Levels ("RSLs") for industrial/commercial soil and tapwater, to ensure that the analytical data are sufficient to support a risk-based evaluation of site conditions.
B. Status of Phase II ESA
Phase II ESA field work commenced in June 2025. Dr. Volkov and the Pendleton field team mobilized to the site to perform the soil boring program and install temporary monitoring wells. The Phase II ESA target completion date remains July 1, 2025.
As of the date of this memorandum, preliminary results from the Phase II ESA are pending. Laboratory analytical data from the initial rounds of soil and groundwater sampling have not yet been received. This memorandum will be updated and supplemented upon receipt of preliminary and final Phase II analytical results.
This section is reserved as a placeholder for the following information, which will be incorporated into the updated memorandum:
• Summary of soil sampling results, including concentrations of target analytes by boring location and depth interval, compared to applicable Virginia VRP Tier I screening levels and EPA RSLs.
• Summary of groundwater sampling results, including concentrations of target analytes by monitoring well location, compared to applicable groundwater screening criteria.
• Spatial and vertical delineation of any contamination identified, including the areal extent and depth of exceedances.
• Assessment of whether identified contamination is consistent with historical pesticide application patterns or whether localized "hot spots" exist that may be associated with pesticide storage and mixing activities near the former agricultural structures.
C. Anticipated Outcomes and Risk Assessment (Preliminary)
While the Phase II ESA results are pending, it is possible to outline the range of anticipated outcomes and their implications for the Project based on Dr. Volkov's preliminary assessment and professional experience with similar agricultural sites in the Northern Virginia and Piedmont region:
Scenario 1 — Below Screening Levels: If concentrations of pesticides, metals, and other target analytes in soil and groundwater are below the applicable Virginia VRP Tier I screening levels for industrial/commercial land use, the REC identified in the Phase I ESA may be effectively downgraded, and no further investigation or remediation may be required for the intended data center use. In this scenario, Pendleton would issue a "No Further Action" recommendation in the Phase II report, subject to standard caveats, and the environmental due diligence would be considered satisfactorily completed. This is a reasonably plausible outcome for the portion of the investigation area that was used for general row crop agriculture, where pesticide application rates were typically lower than in orchard operations.
Scenario 2 — Localized Exceedances Requiring Remediation: If pesticide or metals concentrations exceed screening levels in localized areas — particularly near the former agricultural building foundations — remediation or risk management measures may be required. The following remediation options would be evaluated:
(a) Excavation and Off-Site Disposal: Removal of impacted soils to a depth and lateral extent sufficient to achieve compliance with screening levels, followed by transportation and disposal at a permitted landfill facility. This is typically the most straightforward remediation approach for localized, shallow soil contamination but may be costly if the volume of impacted soil is significant.
(b) Soil Capping or Engineering Controls: Installation of an impervious cap (e.g., asphalt, concrete, or engineered soil cover) beneath building pads or hardscape in the affected area to prevent exposure to contaminated soils. This approach may be particularly well-suited to the Stonebridge Parcel given that the 4.2-acre northwest quadrant is currently planned as a location for structured parking and stormwater management facilities, which would inherently provide an impervious cover.
(c) Institutional Controls: Recording an environmental covenant or other activity and use limitation ("AUL") against the property pursuant to the Virginia Uniform Environmental Covenants Act (Va. Code § 10.1-1238 et seq.) to restrict land use to industrial/commercial purposes and impose management requirements (e.g., soil management plan, groundwater use restrictions) to protect against exposure pathways.
(d) Virginia DEQ Voluntary Remediation Program Enrollment: If contamination is significant, IHDC may elect to enroll the northwest quadrant of the Property in the Virginia DEQ Voluntary Remediation Program ("VRP") established under Va. Code § 10.1-1429.1 et seq. The VRP provides a regulatory framework for investigation and remediation under DEQ oversight, culminating in the issuance of a "Certification of Satisfactory Completion of Remediation" that provides comfort to property owners, lenders, and future transferees regarding the adequacy of the remediation. VRP enrollment, however, involves registration fees, additional consulting costs, and a regulatory timeline that may extend beyond the current due diligence period.
Scenario 3 — Widespread Contamination Requiring Material Remediation: If pesticide or metals contamination is found to be widespread throughout the 4.2-acre northwest quadrant at depths and concentrations requiring extensive remediation, the costs, timeline, and regulatory complexity would increase significantly. While this scenario is considered less likely based on Pendleton's preliminary assessment, it cannot be ruled out until the Phase II analytical data are available.
Preliminary Cost Estimates: Pendleton has provided an initial order-of-magnitude estimate for potential remediation costs, which is subject to significant revision upon receipt of the Phase II results. The current estimated range is as follows:
• Lower End ($150,000): Reflects a scenario involving localized soil removal (e.g., 500–1,000 cubic yards) from a limited area near the former agricultural building foundations, with off-site disposal and minimal backfill and compaction. This scenario assumes no groundwater contamination requiring treatment.
• Upper End ($600,000): Reflects a more extensive remediation scenario involving broader soil removal across a significant portion of the 4.2-acre area, potential soil capping or engineering controls for areas not slated for excavation, groundwater monitoring well installation and sampling over a multi-year period, and potential VRP enrollment and associated regulatory compliance costs.
These estimates do not include legal fees, project management costs, or potential construction schedule impacts. The remediation cost estimate will be refined upon receipt of the Phase II analytical data and the development of a site-specific remediation work plan by Pendleton.
Site Plan Considerations: As noted above, the 4.2-acre northwest quadrant is currently planned as a location for structured parking and stormwater management facilities, rather than a primary building pad for data center structures. This is a favorable circumstance from an environmental management perspective, as it may facilitate the use of engineering controls (e.g., an impervious cap provided by the parking structure or stormwater basin liner) as a component of the remediation strategy, potentially reducing the need for more invasive and costly excavation and disposal. The site plan configuration should be coordinated with Lumen Ridge Engineering, PLLC (Carlos Esteban, PE) to optimize the alignment between the development plan and any environmental controls that may be required.
V. IMPLICATIONS FOR THE STONEBRIDGE PARCEL ACQUISITION
A. Due Diligence Timing
The timing of the Phase II ESA relative to the contractual due diligence period is a critical consideration. The Phase II ESA completion target of July 1, 2025, provides approximately thirteen calendar days of buffer before the due diligence period expires on July 14, 2025. While this buffer should be sufficient to allow the team to review the Phase II results, assess their implications, and make an informed decision regarding the acquisition, it leaves limited margin for delays or complications.
If the Phase II results are delayed beyond the July 1, 2025 target — due to laboratory turnaround times, adverse weather affecting field work, or other factors — or if the results indicate that additional investigation is necessary (e.g., expanded sampling to delineate the full extent of a contamination plume, additional groundwater monitoring rounds, or supplemental analysis of unexpected contaminants), the thirteen-day buffer may prove insufficient. In that event, IHDC will face a decision point: either (a) terminate the PSA and receive a return of the earnest money deposit before the due diligence period expires, or (b) negotiate an extension of the due diligence period with Blackthorn.
As a proactive measure, C&H has prepared a First Amendment to Stonebridge PSA (Due Diligence Extension), which would extend the due diligence period by an additional thirty days to August 13, 2025. Execution of this amendment requires the consent of Blackthorn. We recommend that Douglas Fairchild or Cynthia Ho coordinate with Harrison Poole at Whitfield, Poole & Stratton LLP to assess Blackthorn's willingness to grant an extension if it becomes necessary. Given Blackthorn's financial interest in completing the transaction, we anticipate that a reasonable extension request would likely be favorably received, although Blackthorn may seek concessions (e.g., release of additional earnest money or an increase in the purchase price) in exchange for the extension.
The team should also be aware that the second tranche of the earnest money deposit ($1,462,500) becomes non-refundable and is due upon expiration of the due diligence period. If the due diligence period expires without termination or extension, IHDC's total earnest money exposure will increase to $2,925,000. Priya Dasgupta (CFO) should be advised of this financial exposure and the circumstances under which it could be triggered.
B. Purchase Agreement Considerations
The Stonebridge PSA contains environmental representations and warranties by Blackthorn in the applicable section of the agreement. C&H should confirm that these representations adequately address the REC identified in the Phase I ESA. Specifically, the following matters should be evaluated:
• Whether Blackthorn's representations regarding the environmental condition of the Property are sufficiently broad to encompass the historical use of organochlorine and organophosphate pesticides and any resulting soil or groundwater contamination.
• Whether the representations include a disclosure schedule or exception for known environmental conditions, and whether the identified REC has been disclosed by Blackthorn in the disclosure schedules or seller's certificate.
• Whether the PSA provides for a post-closing environmental indemnity from Blackthorn with respect to pre-existing environmental conditions, and if so, whether the survival period, cap, and basket provisions of such indemnity are adequate given the potential remediation costs.
• Whether IHDC should negotiate a purchase price reduction to account for estimated remediation costs, particularly if the Phase II results indicate that material remediation is required. A purchase price reduction has the advantage of providing IHDC with immediate financial relief rather than relying on a contingent indemnity claim against Blackthorn post-closing.
The PSA permits IHDC to terminate the agreement and receive a return of the earnest money deposit at any time during the due diligence period if environmental conditions are unacceptable to Buyer. This termination right provides IHDC with significant leverage in negotiating remediation cost allocation and other environmental protections. However, the termination right expires at the end of the due diligence period, underscoring the importance of completing the Phase II ESA and reaching a resolution with Blackthorn before July 14, 2025.
C. Impact on Construction Loan and Lender Requirements
The construction lender syndicate — Summit National Bank, N.A. (Administrative Agent), Cascade Commercial Lending Corp., and Harborview Trust Company — will require delivery of satisfactory Phase I and Phase II ESA reports as conditions precedent to closing the $390,000,000 senior secured construction loan facility. The loan closing is currently targeted for October 15, 2025. Any material environmental findings in the Phase II ESA could affect the lender syndicate's underwriting and approval process.
The Environmental Indemnity Agreement to be executed by Stonebridge Campus Holdings LLC (the borrower entity) and Ironhaven Data Centers LLC (as guarantor) in favor of the lender syndicate will cover environmental liabilities associated with the campus parcels. The scope and terms of the Environmental Indemnity Agreement should be reviewed by C&H to ensure that IHDC's indemnification obligations are appropriately bounded and that any carve-outs for pre-existing conditions or seller-allocated environmental liabilities are preserved.
Lender's counsel, Redmond & Calloway LLP (Victor Redmond), should be kept apprised of the Phase II findings and any remediation requirements on a timely basis. It is our recommendation that a summary of the Phase I ESA findings be provided to the lender syndicate and lender's counsel as part of the due diligence reporting process, with the full Phase II ESA report to follow upon its completion. Proactive communication with the lender syndicate is advisable to avoid surprises that could delay the loan closing.
If enrollment in the Virginia DEQ Voluntary Remediation Program is ultimately required, or if an environmental covenant or other AUL must be recorded against the Property, the lender syndicate will likely require review and approval of any such instrument. Activity and use limitations recorded against the Property could affect the lender's assessment of its deed of trust collateral, and the lender may impose conditions regarding the form and substance of any environmental covenant. The interaction between the environmental covenant and the lender's title insurance policy should be carefully evaluated.
D. Impact on Title Insurance
Fidelitas Title & Escrow, Inc. ("Fidelitas") is serving as the title agent for the Stonebridge Parcel acquisition, with the owner's policy being underwritten by Sovereign Title Insurance Company. The title commitment for the Stonebridge Parcel, with an effective date of April 3, 2025, provides for an owner's policy in the amount of $58,500,000. A lender's title insurance policy in the amount of $390,000,000 will also be required by the construction lender syndicate.
If the Phase II ESA results lead to the recording of any environmental liens, environmental covenants, or other AULs against the Property, these instruments would constitute additional title exceptions that would need to be reflected in both the owner's and lender's title policies. C&H should coordinate with Fidelitas and Sovereign to ensure that: (a) any environmental covenants are properly reflected as exceptions in the title policies; (b) the title insurer does not take an overly broad exception that would undermine the coverage provided by the policies; and (c) any endorsements that may be available to insure over or limit the impact of environmental exceptions are obtained.
Given the lender's significant collateral interest in the Property, the form of any environmental covenant and its treatment in the lender's title policy should be coordinated among C&H, Redmond & Calloway LLP (lender's counsel), Fidelitas, and Sovereign prior to loan closing.
E. Impact on Entitlements / ZMOD
The ZMOD application for the Stonebridge Parcel (expected Docket No. ZMOD-2025-0038, filing target May 30, 2025) may need to address environmental conditions on the Property as part of the site plan narrative or supporting documentation submitted to Loudoun County. While the ZMOD process is primarily a zoning entitlement proceeding, Loudoun County staff and the Board of Supervisors may inquire about environmental conditions, particularly given the agricultural history of the Property and the potential for public scrutiny of a large-scale data center development.
C&H should coordinate with Ashcroft & Wynn, P.C. (Thomas Ashcroft, land use counsel) and Cornerstone Land Use Consulting, LLC (Alan Mercer, land use consultant) regarding any Loudoun County requirements for disclosure of environmental conditions in the ZMOD application package. The team should assess whether the ZMOD narrative should proactively acknowledge the environmental due diligence process and any remediation commitments, or whether it is preferable to address environmental matters only if raised by County staff during the review process.
The proffer statement for the ZMOD application, which is estimated at approximately $2,400,000 (based on a rate of $5.00 per square foot of approximately 480,000 square feet of gross floor area), may potentially include commitments related to environmental remediation or environmental stewardship. If the proffer statement includes environmental-related commitments, these should be carefully drafted to ensure consistency with the Phase II ESA findings and any remediation strategy that may be adopted. IHDC should avoid committing to remediation measures in the proffer statement that exceed what is required under applicable environmental regulations, as such commitments would become legally binding conditions of the zoning approval.
VI. COORDINATION WITH OTHER DUE DILIGENCE WORKSTREAMS
The environmental due diligence findings intersect with several other workstreams associated with the Stonebridge Data Center Campus development. Coordination among the various consultants, contractors, and professional advisors is essential to ensure that environmental considerations are properly integrated into the overall project plan.
A. Geotechnical Investigation
Brannigan Geotechnical Engineering, LLC ("Brannigan") is conducting geotechnical investigations on the Stonebridge Parcel for the purpose of foundation design and site preparation planning. The geotechnical borings are being performed across the entire 62.0-acre parcel, including the northwest quadrant. Neil Brannigan, PE, the firm's principal, should be asked to report any observations from the geotechnical borings in the northwest quadrant that may be relevant to the environmental assessment, including unusual soil odors, discoloration, staining, or the presence of debris that could indicate historical chemical storage or disposal. Similarly, the Pendleton team should be made aware of the geotechnical boring locations and logs to avoid unnecessary duplication of effort and to maximize the information gained from subsurface investigation activities on the Property. Coordination between Brannigan and Pendleton should be facilitated through IHDC's development team or C&H to ensure that data sharing occurs promptly and completely.
B. Civil / Site Design
Lumen Ridge Engineering, PLLC ("Lumen Ridge") is the civil and site design engineer for the Stonebridge Data Center Campus. Carlos Esteban, PE, is the project engineer. The site plan for the Campus should be reviewed and, if necessary, modified to accommodate any environmental controls that may be required in the northwest quadrant as a result of the Phase II ESA findings. Specifically, Lumen Ridge should be prepared to:
• Incorporate an impervious cap design (e.g., structured parking pad, stormwater basin liner, or hardscape) in the northwest quadrant area if a soil capping strategy is adopted as a remediation measure.
• Designate locations for permanent groundwater monitoring wells, if required, ensuring that these locations do not conflict with planned improvements, utilities, or grading plans.
• Address stormwater management considerations associated with any soil disturbance or remediation activities in the northwest quadrant, including erosion and sediment control during any excavation work.
• Coordinate the wetlands delineation (being conducted by Lumen Ridge under the civil scope) with the environmental assessment to confirm that any wetland areas near the northwest quadrant are properly buffered and protected during remediation activities.
C. EPC Contract
The Engineering, Procurement, and Construction ("EPC") Agreement with Titan-McAllister Construction Group, LLC ("Titan-McAllister") provides for a Guaranteed Maximum Price ("GMP") of $412,000,000 for the construction of the Stonebridge Data Center Campus. The EPC scope includes demolition of existing structures and site work.
Any environmental remediation required in the northwest quadrant should be carefully evaluated with respect to the EPC Agreement to determine whether it will be treated as: (a) a pre-construction activity to be performed directly by the owner (IHDC) prior to Titan-McAllister's mobilization to the affected area, or (b) a change order under the EPC Agreement, with the work performed by Titan-McAllister or a designated subcontractor under the GMP framework.
We recommend that any required remediation be designated as an owner-directed pre-construction activity performed prior to the commencement of EPC work in the northwest quadrant. This approach has several advantages: it avoids triggering the GMP change order mechanism and the associated markup and fee provisions in the EPC Agreement; it allows IHDC to retain direct control over the remediation contractor selection and scope; and it avoids potential disputes with Titan-McAllister regarding scope, schedule, and cost impacts associated with encountering environmental contamination during construction activities. IHDC's development team (Leonard Castellano) should be consulted regarding the feasibility of this approach from a construction scheduling perspective.
Additionally, the demolition of remnant agricultural structures in the northwest quadrant, which falls within the EPC scope, will need to address the lead-based paint and potential asbestos-containing materials identified in the Phase I ESA. Titan-McAllister's demolition subcontractor should be required to conduct a pre-demolition asbestos inspection and to implement appropriate abatement procedures for both lead-based paint and any ACM identified.
D. Insurance. The builder's risk insurance policy for the Project ($412,000,000 in coverage, through Great Basin Surety & Insurance Corp.) typically contains a pollution exclusion that would preclude coverage for losses arising from the discovery, removal, or remediation of environmental contamination on the Project site. Given the identification of a REC in the Phase I ESA and the pending Phase II investigation, it is prudent to evaluate whether supplemental environmental insurance coverage is warranted.
C&H should direct Northgate Insurance Brokerage, LLC (William Keane, lead broker) to evaluate the following insurance products:
• Contractor's Pollution Liability ("CPL") Policy: A CPL policy would provide coverage for third-party claims and cleanup costs arising from pollution conditions discovered or exacerbated during construction activities. This coverage may be particularly relevant if Titan-McAllister's construction work in or near the northwest quadrant disturbs contaminated soils and causes or exacerbates the migration of contaminants.
• Environmental Insurance (Pollution Legal Liability) Policy: A broader environmental insurance policy could provide coverage for pre-existing contamination conditions on the Property, including cleanup costs, third-party bodily injury and property damage claims, and business interruption losses associated with environmental contamination. The availability and cost of such coverage will depend on the Phase II ESA findings and the insurer's assessment of the environmental risk profile of the Property.
The insurance evaluation should be coordinated with the Phase II ESA results, as the underwriting for environmental insurance products will typically require review of the ESA reports and any remediation plans.
VII. PENDING ACTION ITEMS AND RECOMMENDATIONS
Based on the Phase I ESA findings and the pending Phase II ESA investigation, C&H recommends the following action items and next steps:
1. Await Phase II ESA Final Report. The Phase II ESA final report is targeted for receipt on or before July 1, 2025. Dr. Renata Volkov of Pendleton Environmental Associates is to deliver the final report directly to C&H and IHDC (Leonard Castellano). Upon receipt, C&H will review and analyze the findings and update this memorandum accordingly. Any preliminary results or interim communications from Pendleton should be forwarded to C&H immediately upon receipt.
2. Brief the Client. C&H should schedule a call or meeting with IHDC's management team — Marcus Thorne (CEO), Priya Dasgupta (CFO), and Leonard Castellano (EVP of Development) — to advise them of the Phase I ESA findings, the Phase II ESA status, and the range of potential outcomes and their implications for the acquisition, development budget, and construction timeline. This briefing should include a discussion of IHDC's risk tolerance with respect to environmental conditions and its preferred strategy for remediation cost allocation (e.g., purchase price adjustment, seller indemnity, or absorption within the project contingency budget).
3. Due Diligence Extension Contingency. The First Amendment to Stonebridge PSA (Due Diligence Extension) has been prepared and is available for execution in the event that the Phase II ESA results are delayed, inconclusive, or require additional investigation beyond the July 14, 2025 due diligence expiration date. If it becomes apparent that an extension may be needed, C&H should coordinate promptly with Harrison Poole at Whitfield, Poole & Stratton LLP (Blackthorn's counsel) to obtain Blackthorn's consent to the extension. Early engagement with WPS is recommended to preserve goodwill and maximize the likelihood of a cooperative outcome.
4. Lender Communication. C&H should provide a summary of the Phase I ESA findings to the construction lender syndicate — Summit National Bank, N.A. (Karen Ellsworth, relationship manager), Cascade Commercial Lending Corp. (David Rennick), and Harborview Trust Company (Susan Applegategate) — and to lender's counsel, Redmond & Calloway LLP (Victor Redmond), as part of the ongoing due diligence reporting process. The full Phase II ESA report should be delivered to the lender syndicate and lender's counsel promptly upon its completion. Proactive and transparent communication with the lenders is essential to maintaining their confidence in the Project and avoiding delays to the October 15, 2025 loan closing target.
5. Remediation Cost Analysis. Upon receipt of the Phase II ESA results, C&H should coordinate with Pendleton to develop a detailed, site-specific remediation cost estimate. This estimate should be compared against the available budget allocations within the Project budget, including the $14,200,000 entitlements and soft costs line item and the $34,900,000 contingency and reserves line item, to assess the financial impact of remediation. The team should also evaluate the feasibility of allocating remediation costs to Blackthorn through a purchase price adjustment, seller-funded remediation, or post-closing environmental indemnity. The appropriate allocation strategy will depend on the magnitude of the remediation costs, IHDC's negotiating leverage, and Blackthorn's willingness to participate in the cost.
6. Environmental Insurance. C&H should direct Northgate Insurance Brokerage, LLC (Willi

PRIVILEGED AND CONFIDENTIAL ATTORNEY WORK PRODUCT

MEMORANDUM

I. EXECUTIVE SUMMARY

II. BACKGROUND AND SCOPE OF ENGAGEMENT

V. IMPLICATIONS FOR THE STONEBRIDGE PARCEL ACQUISITION

VI. COORDINATION WITH OTHER DUE DILIGENCE WORKSTREAMS

VII. PENDING ACTION ITEMS AND RECOMMENDATIONS

Record

Parties

Dates

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