SUBJECT:

FROM:

TO:

THRU:

ATTN:

[SSUE:

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION Ill

1650 Arch Street Philadelphia, Pennsylvania 19103-2029

0 EC 1 2 20'14

Approval of a Request for a Removal Action at the Baghurst Drive NPL Site Harleysville, Montgomery County, Pennsylvania

David P. Wright, Director 4{WI/ ~v/'/V .jl'"gvJ Office of Preparedness and~~spon~31 30~

Mathy Stanislaus, Assistl'lnt Administrator Office of Solid Waste and Emergency Response

Reggie Cheatham, Acting Director Office of Emergency Management

Joshua Woodyard, Acting Director Program Operations and Coordination Division

The attached Memorandum is a request for funds to conduct a time-critical Removal Action at the Baghurst Drive Site (EPA ID No. PAN000306939), Harleysville, Montgomery County, Pennsylvania (Site). The Site evaluation documented a threat to public health or welfare or the environment due to a contaminated groundwater plume that is affecting private drinking water wells at the Site. The groundwater plume includes the hazardous substances 1, 1, !-trichloroethane (1,1,1-TCA), 1,1-dichloroethene (I, 1-DCE), I, 1-dichloroethane (I, I-DCA), trichloroethylene (TCE), and I ,4-dioxane.

The work described in this Action Memorandum will be performed pursuant to CERCLA and the NCP. To mitigate the threat, CERCLA funding is necessary to conduct a Removal Action pursuant to Section 300.415 of the NCP, 40 C.F.R. § 300.415, to prevent the release and/or substantial threat of release of hazardous substances from the Site and to protect public health, welfare, and/or the environment. To mitigate the threats identified in this request, the OSC requests a project ceiling of$1,983,750, ofwhich $1 ,733,750 is from the Regional Removal Allowance.

Because conditions at the Site continue to meet criteria set fo1ih in Section 300.415 of the NCP, and the Region finds that conditions at the Site described within the attached Action Memorandum constitute a public health threat warranting immediate attention, I have approved this request for additional funding for the Removal Action. This approval is provided pursuant to EPA delegation of authority 14-2 which gives the Director of the Office of Preparedness and Response, Hazardous Site Cleanup Division, EPA Region Ill, authority to approve CERCLA Removal Actions.

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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION III

1650 Arch Street Philadelphia, Pennsylvania 19103-2029 DEC 1 2 c:Ui4

SUBJECT: Request for Approval and Funding for a Removal Action at the Baghurst Drive Site, Harleysville, Montgomery County, Pennsylvania

FROM:

TO:

THRU: Gerald T. Heston 6. ~ d-r Eastern Response B~3HS31) (T-

I. PURPOSE

The purpose of this Action Memorandum is to request and document approval ofthe time-critical Removal Action described herein for the Baghurst Drive Site (EPA ID No. PAN000306939), Harleysville, Montgomery County, Pennsylvania (Site). The Site is located at and around the intersection ofBaghurst Drive and Hendricks Road and in a rural residential area. Site evaluation activities were performed in June 2014 in accordance with the National Oil and Hazardous Substances Contingency Plan (NCP), 40 CFR Part 300. The Site evaluation documented a threat to public health or welfare or the environment due to a contaminated groundwater plume that is affecting private drinking water wells at the Site. The groundwater plume includes the hazardous substances 1,1, !-trichloroethane (1, 1,1-TCA), 1, 1-dichloroethene (1,1-DCE), 1,1-dichloroethane (1,1-DCA), trichloroethylene (TCE), and 1,4-dioxane. The On­Scene Coordinator (OSC) has determined that the Site meets the criteria in Section 300.415 of the NCP for initiating a Removal Action. Funding in the amount of$1,983,750, ofwhich $1,733,750 comes from the Regional Removal Allowance, is necessary to address the threats identified in this Action Memorandum.

II. SITE DESCRIPTION AND BACKGROUND

A. Site Description

1. Removal Site Evaluation

In June 2014, a removal site evaluation was performed for the residential drinking water wells that are impacted by the contaminated groundwater plume. The plume is reported to have impacted 27 residential drinking water wells, including a common well that services 10

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residences. The Site location and sample locations are illustrated in Figures 1 and 2 (Attachment 1). EPA tasked the Superfund Technical Assessment and Response Team (START) contractor to collect 13 samples in conjunction with Pennsylvania Department of Environmental Protection (PADEP) semi-annual sampling. The 13 residential groundwater samples, including one duplicate sample, from nine residences were collected at the same locations as a portion of the residences being monitored by P ADEP. Ten samples, one from each residence and one duplicate, were collected from a location prior to the P ADEP installed treatment system. At three homes, an additional sample was collected from a post-treatment system location. All samples were analyzed under the EPA Contract Lab Program (CLP) for trace Volatile Organic Compounds (VOCs) and Semi volatile Organic Compound Modified Analysis 1679.3 for 1,4-dioxane.

Results indicated that concentrations of 1,1, 1-TCA and 1,1-DCE were detected in all samples collected prior to the treatment systems from the nine residential drinking water wells. Concentrations of 1,1,1-TCA ranged from 0.81 to 1,000 micrograms per liter (~g/L) and concentrations of 1,1-DCE ranged from 0.59 to 700 ~g/L. Four ofthe nine residences sampled contained concentrations of 1,1, 1-TCA exceeding the Maximum Contaminant Level (MCL) of 200 ~g/L, and all but one sample contained concentrations of 1 ,1-DCE exceeding the MCL of 7 ~g/L. Concentrations of 1,1,1-TCA and 1,1-DCE were not detected in the three post-treatment system samples. TCE was detected above the quantitation limit of 0.5 ~giL in samples collected prior to the treatment system from six of the nine drinking water wells. Only one of the samples, with a concentration of 8.2 ~g/L, exceeded the MCL of 5 ~g/L. TCE was not detected in the three post-treatment system samples. One pre-treatment sample contained 0.81 ~g/L tetrachloroethene, which is below the MCL of 5 ~g/L.

Both 1,1-DCA and 1,4-dioxane were also detected in the samples; however, there is currently no MCL for these chemicals. The analytical results for 1 ,4-dioxane and 1, 1-DCA were compared with EPA Regional Screening Levels (RSLs) for tap water. Concentrations of 1, I­DCA were detected in eight of the nine residential drinking water wells sampled at pre-treatment system locations. All but one sample location exceeded the EPA RSL of2.7 ~g/L, ranging from 0.8 to 46 ~g/L. Concentrations of 1 ,4-dioxane were detected in all the residential drinking water samples collected from pre-treatment system locations ranging from 2.1 to 36 ~giL, exceeding the EPA RSL of 0. 78 ~giL. A post-treatment system sample collected from one of the residences contained 5.7 ~g/L; this concentration is higher than the concentration detected in the pre­treatment sample at this residence.

These results are consistent with the analytical results from P ADEP for the same locations. Additionally, PADEP sampled eight other residences and found concentrations of 1,1,1-TCA ranged from 44.4 to 1,040 ~g/L and concentrations of 1,1-DCE ranged from 38.4 to 787 ~g/L prior to treatment. 1,1-DCA concentrations ranged from 1.9 to 47.5 ~g/L, TCE concentrations ranged from 0.381 to 12.4 ~g/L, and 1,4-dioxane ranged from 5.63 to 68.6 ~g/L. In addition, three of the eight locations sampled showed an increase in 1 ,4-dioxane concentrations after treatment.

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2. Physical Location/Site Characteristics

The Site is located in a rural, residential area in Harleysville, Montgomery County, Pennsylvania. The geographic coordinates ofthe site are 40° 17' 58.14" (40.299483) north latitude and 75° 27' 18.48" (75.455133) west longitude, as measured at the intersection of Hendricks Road and Baghurst Drive.

3. Release or threatened release into the environment of a hazardous substance, or pollutant, or contaminant

Both current and historical analytical results demonstrate a migration of contaminated groundwater into the private residential wells. The groundwater plume includes the hazardous substances 1,1,1-TCA, 1,1-DCE, 1,1-DCA, TCE, and 1,4-dioxane. A total of 18 wells are affected, 1 7 private residential wells and one common well that services 10 homes, impacting a total of27 residences. Sampling has consistently shown levels of these hazardous substances above MCLs or EPA RSLs in the residential wells. Additionally, the most recent sampling event detected 1,1,1-TCA concentrations at or above the Superfund Removal Action Level (RAL) of 1,000 ug/L in two residential wells. There is also evidence that the continued use of the residential wells is influencing the direction of the contaminated groundwater plume, possibly resulting in exposure to increasing levels of contamination and impacts to additional residents.

While P ADEP has currently installed water treatment systems that decrease the levels of most of these contaminants, the 1 ,4-dioxane is not being addressed by the systems. Analytical results demonstrate the carbon treatment systems are in some cases increasing the 1 ,4-dioxane levels likely due to the high water solubility of the chemical. As a result of these findings, P ADEP has been providing bottled drinking water to residents but there is still a dermal and inhalation exposure to 1 ,4-dioxane during bathing or washing. Without the continued maintenance ofthe treatment systems and the delivery of bottled water, the residences would be exposed to hazardous substances at concentrations deemed to be harmful to their health.

PADEP has indicated they no longer have the resources to continue to maintain drinking water deliveries or the monitoring and maintenance of water treatments system and have requested EPA assistance.

4. National Priorities List

The Site was added to the National Priorities List (NPL) on September 16, 2014.

B. Other Actions to Date

In 1999, a homeowner submitted a water sample to the Montgomery County Health Department (MCHD) as required to receive a permit for a residential drinking water well. Analytical results of the water sample indicated concentrations of 1, 1,1-TCA above the EPA

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National Primary Drinking Water Standard Maximum Contaminant Level (MCL) of200 micrograms per liter (!!g/L). As a result, the MCHD collected samples from several surrounding residential drinking water wells in the area and found the wells contained one or more VOCs, such as 1,1-DCE; 1,1,1-TCA; TCE; and vinyl chloride, as well as 1,1-DCA and 1,2-dichloroethene (1,2-DCE), at concentrations above MCLs. In November 1999, MCHD contacted P ADEP regarding the presence of chlorinated solvents in residential wells. PADEP immediately began supplying 27 residences with bottled drinking water and subsequently equipped the homes with carbon filtration systems.

Since 2000, P ADEP has been periodically collecting water samples from homes and the common well with treatment systems to monitor performance and system efficiency. In 2004 this sampling was expanded to include analyzing for 1 ,4-dioxane, which was subsequently detected in some of the affected wells. Because ofthe high water solubility of this compound, the treatment systems were not effectively removing the 1 ,4-dioxane. Based on these findings, P ADEP has been supplying bottled water for drinking purposes to the affected 27 residences.

In April2001, PADEP began an investigation into the source ofthe VOC contamination. This investigation included several sampling events over time including soil borings, collecting soil samples, installing bedrock monitoring wells, collecting ground water samples from the monitoring wells between July 2001 and January 2003, and the collection of surface water samples from seeps and streams in February, March-April, and November 2002. The investigation focused on a 29-acre farm property located on Hendricks Road. While analytical results indicated the presence of chlorinated VOCs (primarily 1,1,1-TCA, 1,1-DCE, 1,1-DCA, vinyl chloride, and TCE) in soil, ground water and surface water, EPA has concluded that there is not yet enough evidence to identify the farm property as a primary or significant source of the ground water contamination.

Additionally, PADEP also investigated options for an alternate local water source in 2007 and 2012. The investigation included upgradient well installation and pump testing. Analytical results of the potential supply wells revealed naturally occurring lead and arsenic concentrations above their respective MCLs. As a result, any water supply from these sources would require additional treatment before use. Pump testing also revealed a large pumping influence in nearby residential drinking water wells.

C. State and Local Authorities' Roles

The Commonwealth of Pennsylvania has requested EPA assistance in continuing to respond to conditions at the Site and will continue to be involved. P ADEP and local authorities have requested that the OSC continue assessment and response activities in order to ensure protection of human health in a timely manner. The OSC will continue to coordinate with PADEP, Pennsylvania Department of Health (PADOH), and local authorities.

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III. THREATS TO PUBLIC HEALTH OR WELFARE OR THE ENVIRONMENT, AND STATUTORY AND REGULATORY AUTHORITIES

There have been, and continue to be, releases and threatened releases of hazardous substances from the Baghurst Drive Site into the environment which, under current conditions, present a threat to public health, welfare and/or the environment.

Section 300.415 ofthe NCP lists the factors to be considered in determining the appropriateness of a Removal Action, Paragraphs (b) (2) (i), (ii), and (vii) of Section 300.415 directly apply as follows to the conditions as they exist at the Baghurst Drive Site.

A. 300.415 (b)(2)(i) "Actual or potential exposure to nearby human populations, animals, or the food chain from hazardous substances or pollutants or contaminants"

The Site is characterized by elevated levels of chlorinated VOCs including 1,1, 1-TCA, 1,1-DCE,1,1-DCA, TCE, and 1,4-dioxane in the well water of nearby residences that rely on groundwater as the sole source of drinking water. These contaminants are hazardous substances as defined in Section 101(14) ofCERCLA, 42 U.S.C. § 9601(14), and are listed as such in 40 C.P.R.§ 302.4. Several ofthe contaminants including 1,1-DCE, 1,4-dioxane and TCE are classified by EPA as probable human carcinogens. The most recent sampling event shows 11 wells have 1,1,1-TCA concentrations exceeding the current MCL of200 ~-tg/L, 16 wells have 1,1-DCE concentrations exceeding the current MCL of7 ~-tg/L, and 2 wells have TCE concentrations exceeding the current MCL of 5 ~-tg/L. No MCLs exist for 1,1-DCA or 1,4-dioxane but a comparison to EPA RSLs show 12 wells have 1,1-DCA concentrations exceeding the RSL of2.7~-tg/L and 17 wells have 1,4-dioxane exceeding the RSL of0.78 ~-tg/L.

The source of the contaminated groundwater continues to be investigated and has not yet been fully identified. Groundwater samples collected upgradient of the residential wells have shown 1,1, 1-TCA with a maximum concentration of 18,000 flg/L, 1, 1-DCE with a maximum concentration of2,300 J.tg/L, TCE with a maximum concentration of 58 J.tg/L and 1,4-dioxane with a maximum concentration of 220 J.tg/L. The plume is likely to continue to infiltrate the affected residential wells and could possibly affect additional downgradient residences in the future if current levels of groundwater use continue in the area.

B. 300.415(b )(2)(ii) "Actual or potential contamination of drinking water supplies or sensitive ecosystems"

A cluster of27 residences located to the south and downgradient of the suspected plume area are the focus of the Removal Action. A total of 17 private residential wells and a common well that services 10 homes are affected by contaminated groundwater. Approximately 55 people reside in the affected homes and rely on groundwater as their primary source for drinking

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water. Current and historical sampling demonstrate several hazardous substances including 1,1,1-TCA, 1,1-DCE, 1,1-DCA, and 1,4-dioxane have been routinely detected above MCLs or RSLs in the affected area. In addition, the most recent sampling event showed 1,1, 1-TCA has been detected about the removal action level in two of the wells.

C. 300.415 (b) (2) (vii) "The availability of other appropriate federal or state response mechanisms to respond to the release"

P ADEP has been investigating this Site since 2000, has installed treatment systems in the affected residences and has investigated other potential sources of drinking water in the area. In 2013, PADEP referred the Site to EPA site assessment for potential listing on the NPL and continued to negotiate with local officials in an effort to establish another drinking water source for the Site. In March 2014, PADEP indicated it did not have the resources to continue to maintain treatment systems and drinking water delivery indefinitely and asked for EPA assistance. There are no other state or federal response mechanisms to respond to this situation.

IV. ENDANGERMENT DETERMINATION

Actual or threatened releases ofhazardous substances from this Site, if not addressed by implementing the response action selected in this Action Memorandum, may present an imminent and substantial endangerment to public health, welfare, or the environment. The source of the groundwater contamination at the Site has not yet been sufficiently identified. While the currently installed water treatment systems are reducing levels of many of the identified contaminants, the systems require constant maintenance and monitoring and they do not address the 1 ,4-dioxane contamination. There is also evidence that the treatment systems might be increasing the levels of 1 ,4-dioxane in the treated water. As a result, P ADEP is currently supplying bottled drinking water to residents. The Site was recently listed on the NPL and additional investigation will occur to identify the source of hazardous substances and to restore the aquifer to beneficial use. This process has just begun but it is not anticipated to be completed quickly given the timeframes required at similar sites. In the meantime, a removal action to extend a public waterline will eliminate the direct exposure of the nearby residences to the contaminated groundwater as well as removing the need for bottled drinking water delivery and continued treatment system monitoring, maintenance, and sampling.

V. PROPOSED ACTIONS AND ESTIMATED COSTS

A. Proposed Actions

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The proposed removal action consists of the following:

1. Mobilize personnel and equipment, including support equipment, to the Site to implement response actions;

2. Provide additional Site security and other measures as necessary to secure the Site;

3. Conduct additional investigation and sampling as needed to determine if additional residential wells are affected by the contaminated groundwater plume;

4. Conduct air monitoring and sampling as needed during the removal action to ensure both worker safety and the safety of the neighboring community;

5. Engineer and extend the public water line to affected residences with hazardous substances detected in well water above MCLs and/or EPA RSLs;

6. Provide bottled drinking water and maintain and monitor currently installed drinking water treatment systems until a public water line is installed;

7. Arrange for the proper abandonment and sealing of existing contaminated wells as required by substantive standards of applicable or relevant and appropriate requirements of State regulations; and

8. Conduct restoration of ground or other facilities disturbed by removal activities (to include backfilling with clean fill/stone, revegetation, damage repair, etc.).

9. Legal transfer (e.g. abandonment, donation) ofwater line to appropriate local authorities.

B. Contribution to Remedial Performance

The proposed Removal Action will contribute to the efficient performance of any long term remedial action at the Baghurst Drive Site. The Site was included on the CERCLA NPL in September 2014 and a final remedial action has not yet been determined. The Removal Action will focus on removing the threat currently posed by the exposure of residents to the contaminated groundwater. This threat will be abated by eliminating this exposure but the Removal Action will not investigate or address the source ofthe hazardous substances.

C. Applicable or Relevant and Appropriate Requirements (ARARs)

The proposed Removal Action will comply with Federal and State ARARs to the extent practicable given the exigencies ofthe situation. The OSC will coordinate with PADEP regarding State ARARs for the Baghurst Drive Site. A letter was sent to P ADEP on December 1, 2014 requesting the identification of State ARARs.

D. Estimated Costs

The proposed distribution of funding is as follows:

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Extramural Costs Proposed Ceiling

Regional Allowance Costs $1,475,Q90 (This 'cost category includes esilinate_s for ERRS contractors, sub~ontractors, letter contracts, orders for services notices to proceeq) aJrernati:ve teGbnol0gy contracts, and inter-agency agreements with other Federal Agencies)

Other Extra.m,uraJ Costs Not Fwtded $250,009 from the Regional Allowance START Contractor Total CLB

Subtotal, Extramural Costs $1,725,000

ExtrronuraJ Costs Contingency ~15% of Subtetal, $258,150 Extramural Costs)

TOTAL REMOVAL PROJEG:T CEILING $1,983,750

VII. EXPECTED CHANGE IN SITUATION SHOULD ACTION BE DELAYED OR NOT TAKEN

If no action is taken or the action is delayed, there may be an increased public health risk due to the prolonged exposure of residents to contaminated drinking water from the Baghurst Drive Site.

VIII. OUTSTANDING POLICY ISSUES

There are no outstanding policy issues related to the proposed Removal Action.

IX. ENFORCEMENT

Direct Extramural Costs Direct Intramural Costs Total Direct Costs

8

$1,983,750 $ 35,000 $2,018,750

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Indirect Cost (77.56% x Direct Costs) Total Costs (Direct and Indirect)

$1,565,743 $3,584,493

The EPA Region III Removal Enforcement Section has been provided with all background information available to pursue Enforcement Actions pertaining to the Baghurst Drive Site (see attached Confidential Enforcement Addendum).

The total EPA costs for this Removal Action based upon full-cost accounting practices that will be eligible for cost recovery are estimated to be $3,584,493. 1

X. RECOMMENDATION

This decision document represents the selected Removal Action for the Baghurst Drive Site in Harleysville, Montgomery County, PA, developed in accordance with CERCLA as amended, and not inconsistent with the NCP. Conditions at the Site continue to meet the NCP Section 300.415(b)(2) factors for a removal and I recommend your approval of the proposed removal action. The total project ceiling will be $1,983,750, ofwhich $1,733,750 comes from the Regional Removal Allowance.

By signing this Action Memorandum, you are also hereby establishing the documents listed below as the Administrative Record supporting the issuance of this Action Memorandum, Pursuant to Section 113(k) ofCERCLA, 42 U.S.C. 9613(k) and EPA delegation No. 14-22.

1. Final Trip Report for the Baghurst Drive Site (Weston Solutions: November 11, 2014).

2. Hazardous Ranking Score (HRS) Documentation Report (Weston Solutions: May 2014).

3. HSCA Response Justification Document- Baghurst Alley Site (Pennsylvania Department of Environmental Protection: November 1999).

1 Direct Costs include direct extramural costs and direct intramural costs. Indirect costs are calculated based on an estimated indirect cost rate expressed as a percentage of site-specific direct costs, consistent with the full cost accounting methodology effective October 2, 2000. These estimates do not include pre-judgment interest, do not take into account other enforcement costs, including Department of Justice costs, and may be adjusted during the course of a removal action. The estimates are for illustrative purposes only and their use is not intended to create any rights for responsible parties. Neither the lack of a total cost estimate nor deviation of actual total costs from this estimate will affect the United States' right to cost recovery.

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4. Hazardous Sites Cleanup Program, Statement of Decision, Baghurst Alley Site (Pennsylvania Department of Environmental Protection: November 2001 ).

5. Technical Fact Sheet- 1,4-Dioxane. (U.S. Environmental Protection Agency Office of Solid Waste and Emergency Response: January 2013).

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Action by the Approving Official:

I have reviewed the above-stated facts and based upon those facts and the information compiled in the documents described above, I hereby determine that the release or threatened release of hazardous substances at and/or from the Site presents or may present an imminent and substantial endangerment to the public health or welfare or to the environment. I concur with the recommended removal action as outlined in the Action Memorandum.

APPROVED:

DISAPPROVED:

Attachments:

1. Figures

, irector Office of Preparedness and · esponse Hazardous Site Cleanup Division EPA Region 3

David P. Wright, Director Office of Preparedness and Response Hazardous Site Cleanup Division EPA Region 3

2. Enforcement Confidential Memo

11

DATE:

DATE:

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' . '

U,SGS 7 .5-Minute Series-Tqpographic Quadrangles:"· Perkiomenville, Pennsylvania.,,?013 ,. •'

Legend

-k Site Location 6 N

PA State Plane, NADB3 1:24,000

.. -=~ .. ~=---Foot 0 2,000

Map Area~

,,..h l forc1 id•ln··

Baghurst Drive Harleysville, Montgomery County, PA

Figure 1 Site Location

TDD#: WS01-14-05-004 Contract: EP-53-10-05 Prepared: 812512014

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® Residences with treatment systems sampled by PADEP and EPA, June 2014

0 Residences with treatment systems sampled by PADEP only, June 2014

J: Residences connected to common weii1744B

Residences with historical VOC &. Detections below MCLs (no treatment system)

N - - - Feet 0 450

Map Area

Baghurst Drive Harleysville, Montgomery County, PA

Figure 2 Site Layout

TDD#: WS01-14-05-004 Contract: EP-53-10-05 Prepared: 8/21/2014

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