UNITED STATES ENVIRONMENTAL PROTECTION AGENCYREGION 2

290 BROADWAYNEW YORK, NY 10007-1866

ACTION MEMORANDUM - RV 4

DATE: AUG 1 5 2019

SUBJECT: Confirmation of a Verbal Authorization, Request for a Ceiling Increase and12-Month Exemption for an Emergency CERCLA Removal Action at the ArsenicMine Site, in the Town of Kent, Putnam County, New York

FROM:

THRU:

TO: Pat Evan ista, Acting DirectorSuperfund and Emergency Management Division

Site ID No.: 022Z

I. PURPOSE

The purpose of this Action Memorandum is to confirm a verbal authorization of funding, requestand document approval of a ceiling increase and 12-month exemption described herein for theemergency CERCLA removal action initiated at the Arsenic Mine Site ("Site") located in theTown of Kent, Putnam County, New York. This is the fourth phase of funding ("RV4") for theremoval action taken by the u.S. Environmental Protection Agency ("EPA") at the Site. Thethree previous phases and funding of the removal action ("RV1, RV2, and RV3") occurred andthe activities were completed to address an arsenic contaminated potable water supply of a singleresidence. Based upon recent investigations, the threat from arsenic contamination has spreadand now includes a total often parcels along Gipsy Trail Road and Mt. Ninham Court. OnApril 1, 2019, the Acting Director of the Emergency and Remedial Response Division, now theSuperfund and Emergency Management Division ("SEMD") granted a verbal authorization offunding for the RV4 activities. The RV4 activities began on April 8,2019 and are ongoing. Theobjective of this RV4 funding is to minimize the threat posed to the public by elevated levels ofarsenic in soils from previous mining activities that took place at the Site.

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The total project ceiling approved for the RV1, RV2 and RV3 activities was $300,000, of which $220,220 was for mitigation contracting. On April 1, 2019, the verbal authorization provided a $200,000 increase to the total project ceiling. This memorandum requests an additional $400,000 total project ceiling increase, of which $258,000 is for mitigation contracting. The proposed new total project ceiling, if approved, will be $900,000, of which $678,220 is for mitigation contracting. Conditions at the Site meet the criteria for a removal action under the Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA”), 42 U.S.C. §§9601-9675, and Section 300.415(b) of the National Oil and Hazardous Substances Pollution Contingency Plan (“NCP”), 40 C.F.R. §300.415(b). The Site is not currently on the National Priorities List (“NPL”) but was proposed to the NPL on June 3, 2019. II. SITE CONDITIONS AND BACKGROUND The Superfund Enterprise Management System (“SEMS”) identification number for this time-critical removal action is NYD982531469. A. Site Description 1. Removal Site Evaluation (“RSE”)

The Site includes ten residential property parcels encompassing approximately 19 acres. The Site includes a former arsenic producing mine located near the intersection of Mt. Ninham Court and Gipsy Trail Road located in a rural residential area in the Town of Kent, Putnam County, New York (see Attachment A). The historical arsenic mine is located on Property P003. The other parcels are located directly adjacent to Property P003 or are surficially downgradient from the mine. Mining activities ceased in approximately 1918. Historical information indicated that no chemical processing occurred on-Site, only ore concentrating. Ore concentrating included crushing, rolling, and slicing the ore to reduce its physical size and to remove less rich overburden rock from the highest concentrations of arsenic found in the arsenopyrite vein. In 1987, at one of the ten residential parcels at the Site, the property owners became ill from ingesting arsenic, which was determined to be from a private drinking water well on that property. The previous removal activities (RV1 – RV3) addressed the drinking water at this one residence, hereinafter referred to as Property P001. In August 2017, EPA began a soil investigation that stemmed from elevated levels of arsenic found in sediments located in a potable water holding tank at Property P001, discovered during the RV3 activities. The soil investigation in August 2017, as well as subsequent investigations in December 2017 and June 2018, indicated the presence of arsenic, a CERCLA hazardous substance as listed in Section 101(14) of CERCLA, 42 U.S.C. § 9601(14), and listed in Table 302.4 of the NCP. Arsenic concentrations were

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found in soils greater than the Removal Management Level (“RML”) of 35 milligrams per kilogram (“mg/kg”) on all ten parcels. A statistically-defensible background study was conducted using data collected by the New York State Department of Environmental Conservation (“NYSDEC”) on the Mt. Ninham Multi-Use Lands, which are adjacent to the ten residential properties. The study included six surface soil samples from each of five identified background study areas. Background threshold values, or “not-to-exceed” values that are used to compare measurements in areas of concern with background measurements, were established as 123.9 to 170.6 mg/kg. EPA selected the most conservative background concentration of 123.9 mg/kg (see Attachment B). At each of the ten residential property parcels, arsenic concentrations were collected in the surface and subsurface soils in six-inch intervals to a depth of two feet. In many areas, it was not possible to obtain samples to that depth due to auger refusal. Samples were collected in a 50-foot by 50-foot grid across properties with a 25-foot by 25-foot grid over suspected high use areas during the first two sampling events (August and December 2017). Some additional samples were collected in other suspect areas such as flood pathways identified by the property owners. During the June 2018 event, samples were collected in 6-inch intervals to a maximum depth of two feet in a 75-foot by 75-foot grid. For all three sampling events, samples were screened using an X-Ray Fluorescence (“XRF”) analyzer. Samples were screened four times and the results were averaged. Fifteen to twenty percent of these samples were additionally selected for Target Analyte List (“TAL”) Metals analysis. XRF results and laboratory analytical results were compared with a 93-98% coefficient value for arsenic. Below are the laboratory and XRF concentration ranges for arsenic for each property sampled. Sampling reports with maps can be found in Attachment C. Site Photographs can be found in Attachment D.

Property # XRF Concentration Range

(mg/kg)

Laboratory Concentration Range

(mg/kg) P001 9 - 54,177 17.5 - 54,900 P002 9 - 34,250 10.3 - 6,820 P003 10 - 30,822 17.6 - 56,000 P004 2 - 3,090 19.6 - 20,600 P005 12 - 131 16 - 181 P006 8 - 320 3.2 - 687 P007 12 - 232 14.5 - 403 P008 10 - 97 9 - 99.5 P009 7 - 4,072 44 - 3,800 P010 4 - 582 3.6 - 364

Mine tailings were observed on properties P001 – P004. Based upon the locations of elevated arsenic surficially downgradient of the mine tailings, it is believed that contamination located on properties P005-P010 is a result of sediment transport from stormwater runoff.

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2. Physical location The Site is located near the intersection of Gipsy Trail Road and Mt. Ninham Road (latitude 41.458245, longitude -73.714458) in the Town of Kent, Putnam County, New York, 10512. The Site consists of ten property parcels, tax IDs: 32.-1-19.2, 32.-1-20, 32.-1-21, 32.-1-22, 32.-1-23, 32.-1-30, 32.-1-31, 32.-1-32, 32.-1-33, and 32.-1-34, totaling approximately 19 acres of which 16 acres were assessed. Three parcels have no structure or residents. These ten parcels are zoned for residential, agricultural, and educational purposes and are bounded by additional mixed use (residential/agricultural) properties to the north, Pine Pond Brook to the east, and Mt. Ninham Multi-Use Properties (New York State Forest Lands) to the west and south. The nearest full-time residences are within the Site boundary, and approximately 75 people live within ½ mile of the Site. Refer to Attachment A for Site Location Maps. This phase of the removal action is only addressing the residential properties with part-time or full-time residents, identified by the following tax IDs: 32.-1-20, 32.-1-22, 32.-1-23, 32.-1-30, 32.-1-32, 32.-1-33, and 32.-1-34. 3. Site characteristics

Residential properties are located adjacent and surficially downgradient from one of two historic arsenic mining shafts that have been abandoned for over 100 years. One of the mine shafts is located on a residentially zoned parcel (P003), Tax ID 32.-1-21, that is owned by a non-profit and used for educational purposes. Property P003, is surrounded by other residential properties and is located at approximately 41.457972 latitude and -73.715285 longitude. The second mine shaft is located on a parcel within the New York State Mt. Ninham Multi-Use Lands, identified by Tax ID 32.-1-15, and is located at approximately 41.456468 latitude and -73.713467 longitude. In addition, seven exploratory pits from historical mining activities are located on this tax parcel. Initial mining and exploratory digging began in 1848 in a search for silver. In 1906-1907, arsenopyrite ore was mined. Ore was concentrated on-Site through physical means, but no chemical process was performed on-Site. Concentrated materials were transported to Mamaroneck in Westchester County, New York for processing; however, this processing did not produce a satisfactory quality product. The only other location suitable for processing was located in England and therefore it was determined to no longer be cost effective to mine this arsenopyrite vein. All mining activities ceased between 1917-1918. In the 1950s it was reported that the mine entrance surrounding residential properties was backfilled. During the same time period, a private ski slope was constructed on properties P003 and P004. An A-framed lodge was built on property P002 as a ski in/ski out lodge. Historical reports also indicate that a rock crushing operation existed at the intersection of Mt. Ninham Court and Gipsy Trail Road, which is believed to be property P001. Rocks were crushed for use as road aggregate; however, it is not known what type of rock material was crushed (mine tailings, outcropped gneiss, etc.). This Action Memorandum funds the fourth phase of the removal action, RV4, at the Site.

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

Arsenic is considered a CERCLA hazardous substance as defined in Section 101(14) of CERCLA, 42 U.S.C. § 9601(14), and listed in Table 302.4 of the NCP, 40 C.F.R. § 302.4. The statutory designation for arsenic as a hazardous substance is Section 307(a) of the Clean Water Act and Section 112 of the Clean Air Act. The Site includes a facility as defined in Section 101(9) of CERCLA, 42 U.S.C. § 9601(9), and the presence of arsenic in the soils at the Site constitutes a “release” or threat of release as defined in Section 101(22) of CERCLA, 42 U.S.C. § 9601(22).

Substances Identified

Statutory Source for Designation as a Hazardous Substance

Arsenic 307(a) CWA, 112 CAA 5. NPL status

The Site was proposed for inclusion on the NPL on June 3, 2019, after ATSDR issued a Public Health Advisory on April 30, 2019 (see Attachment E).

6. Maps, pictures, and other graphic representations

A Site location map is included as Attachment A. RSE sample location maps are included as Attachment C, and photographs are included as Attachment D.

B. Other Actions to Date 1. Previous actions

Following the March 16, 1988 NYSDEC request (see Attachment F), EPA investigated and evaluated the drinking water well at Property P001. On March 24, 1988, with verbal funding approval, EPA arranged for weekly deliveries of bottled water to the residence for drinking purposes under an emergency action (RV1). In April 1988, the Agency for Toxic Substances and Disease Registry (“ATSDR”) recommended that the affected residents at Property P001 be provided with a permanent alternate potable water supply (see Attachment F). In July 1988, EPA installed a precipitation collection system to collect, treat, store, and pressurize rainwater and snowmelt from the residents’ roof. Four concrete tanks, each having a capacity of 3,500 gallons, were installed below ground adjacent to the residence to store up to 14,000 gallons of precipitation water. This phase of the removal action (RV1) was completed on September 29, 1988.

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After encountering recurrent weather-related problems, it was determined that a reliable source of water from precipitation was not sustainable, and the precipitation catchment system was disconnected and reconfigured to a system to receive, store, and sterilize bulk tank truck delivered water. This phase of the removal action (RV2) was initiated on March 1, 1989 and completed on January 10, 1990. The homeowner at the time agreed to purchase the water from a vendor of their choice and to maintain the system. EPA expended approximately $130,220 in mitigation costs during the RV1 and RV2 activities. These actions were effective in providing a safe, reliable, potable water supply to the residents identified as being impacted by the arsenic contamination at the Site. In June 2016, the current residents at Property P001 (not the original owners during the installation of tank system) contacted EPA’s Removal Action Branch (“RAB”) stating that their water system was leaking, resulting in the owners needing to purchase water on a more frequent basis. Investigation into the water system revealed sediment in the water filter cartridge and at the bottom of the storage tanks. EPA determined that during periods of rainfall or snow melt, arsenic contaminated soil was entering the drinking water supply through a tank lid that had become unsealed by build-up of eroded soils from upgradient locations. The tanks were cleaned, and that portion of the system that was used to collect water from precipitation was permanently abandoned. The area around the tank lid was also regraded to ensure proper sealing in the future. This phase of the action, RV3, was initiated on July 26, 2016 and completed on March 28, 2017. EPA expended approximately $22,500 in mitigation costs for this phase of the action. 2. Current actions Detection of elevated levels of arsenic in the sediments found at the bottom of the water holding tanks in 2016 led to the assessment of soils on all ten Site properties. Arsenic levels detected in soils on these properties were identified as an immediate threat to the impacted residents. As a result, a verbal authorization of funding was granted on April 1, 2019. The RV4 activities were initiated on April 8, 2019 and are ongoing. The additional funding requested in this action memorandum is necessary to mitigate the arsenic threats posed by the Site. As of May 30, 2019, EPA has incurred $144.817.91 of the RV4 removal activities.

C. State and Local Authorities’ role 1. State and local actions, to date

On March 16 and 18, 1988, NYSDEC requested EPA’s assistance to conduct a removal action to rectify a contaminated water supply problem in a private well on Gipsy Trail Road in Kent, New York. Concurrently, Putnam County Department of Health conducted drinking water sampling at properties P001 – P010 from 1987 through 1992, except for vacant properties P003, P004, and P007, which did not have drinking water wells. The

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County and EPA also collected soil samples at some of these properties in 1988/1989; however, no additional soil samples were collected/analyzed since that time period until 2017. Concurrent with EPA’s more recent soil investigation on the Site residential parcels, which began in 2017, NYSDEC began an investigation into arsenic on the State Multi-Use Lands as part of its Land Management Unit Study. As part of the NYSDEC investigation, samples were collected by NYSDEC to further a background study by EPA. Additional surface water and sediment samples were collected both upgradient of the residential properties (at Pine Pond) as well as downgradient of the residential properties (in Pine Pond Creek) but upgradient of the State Multi-Use Lands. Other co-located samples were collected in the State Multi-Use Lands and downgradient of the state lands in Putnam County Veteran’s Memorial Park. On April 30, 2019, New York State Department of Health (“NYSDOH”) under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (“ATSDR”) issued a health consultation (see Attachment G). In the Health Consultation, NYSDOH documented its review of shallow surface soil samples (0-6 inches below ground surface) collected by EPA in 2017 and 2018. Results were evaluated for short- and long-term health effects on an individual property-by-property basis. As a result of this consultation, NYSDOH and ATSDR concluded that an immediate and significant threat to human health is posed from short-term ingestion exposure of a child to arsenic in shallow soils with the highest arsenic levels at residential properties. Additionally, NYSDOH and ATSDR concluded that long-term ingestion and dermal exposure of children and adults to arsenic in shallow soils pose a significant threat to human health. 2. Potential for continued State/local response

State and local officials will continue to provide educational information on the effects of arsenic to residents in the area; however, they are not planning on performing any further assessment or response activities at the Site at this time. NYSDEC has indicated that the Site does not meet the threshold for a hazardous waste site nor a mining site. NYSDEC supports EPA’s proposal to take appropriate removal actions necessary to reduce residential soil exposures to arsenic.

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

Arsenic is a hazardous substance as defined by Section 101(14) of CERCLA, 42 U.S.C. § 9601(14), and is listed in Table 302.4 of the NCP, 40 C.F.R. § 302.4. Analytical data from samples collected at the seven Site residential properties indicate that arsenic is present in the surface and subsurface soils at concentrations greater than the EPA RML of 35 mg/kg. Arsenic is also present on six of the residential properties in concentrations greater than the statistically-

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defensible background concentration of 123.9 mg/kg. Arsenic in these concentrations is considered a public health hazard. Arsenic is a carcinogenic compound (human cancer-causing agent), causing skin cancer or the cancer of the liver, bladder, skin, and lungs. Arsenic can be absorbed through the skin, inhaled, or ingested. Arsenic is typically found in seafood in the organic form. This organic form of arsenic is considered non-toxic and is typically excreted from the human body within 48 hours of consumption. Inorganic arsenic, a much more toxic form of arsenic, is typically found in drinking water and soils near previous mining operations. The inorganic form of arsenic, which vegetable plants (fruiting, root, and leafy) may uptake, presents another exposure route for arsenic ingestion. Arsenic may accumulate in the human body in nails, hair, and other keratin-rich tissues. Chronic, or low dose, long-term exposures typically result in skin lesions and peripheral neuropathy when arsenic is either ingested or inhaled. Arsenic exposures also cause issues with dermal, neural, gastrointestinal, and cardiovascular systems. Acute, or high dose, short-term exposures typically result in gastrointestinal, respiratory, hepatic, renal, and hematologic distresses. In acute arsenic poisoning, death can result from cardiovascular collapse. Further details describing the health threat can be found in a collaborative NYSDOH and ATSDR Health Consultation document (Attachment G) and the ATSDR Health Advisory dated April 30, 2019. EPA has determined that the limitation on response to naturally occurring arsenic in its unaltered form as stated in Section 300.400(b)(1) of the NCP, 40 C.F.R. § 300.400(b)(1), does not apply, and that the Site meets the requirements of Section 300.415(b)(2) of the NCP, 40 C.F.R. § 300.415(b)(2), which indicate that a removal action is warranted. Site conditions that correspond to factors that provide a basis for a removal action include: (1) Actual or potential exposure to nearby human populations, animals, or the

food chain from hazardous substances, or pollutants, or contaminants [300.415(b)(2)(i)];

There are actual or potential exposures to human populations from a hazardous substance, arsenic, that was released to the environment. The ten Site parcels contain, are adjacent to, or are surficially downgradient from the historic mine entrance. Four of these properties have mine tailings visible on the ground surface. The remaining six properties are downgradient from the mine tailings and have received sediment transport as a result of stormwater runoff contamination. The Health Consultation prepared by NYSDOH in conjunction with ATSDR, the two agencies jointly concluded that short-term ingestion exposure of a child to arsenic in shallow soils with the highest arsenic levels at residential properties pose an immediate and significant threat to human health.

(2) High levels of hazardous substances, or pollutants, or contaminants in soils largely at or near the surface that may migrate [300.415(b)(2)(iv)];

Surface and near surface soil samples collected by EPA from 2017 through 2018 from the ten Site parcel properties contained arsenic at concentrations as high as

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56,000 mg/kg. Concentrations on all ten properties included arsenic found in concentrations greater than EPA’s RML. Additionally, EPA conducted a statistically-defensible background investigation in which EPA determined that background in this area is to not exceed 123.9 mg/kg. Arsenic was found in concentrations above this statistical background study on nine of the ten parcel properties.

(3) Weather conditions that may cause hazardous substances, or pollutants to

migrate or to be released [300.415(b)(2)(v)]; and

The ten Site parcel properties are located in a rural, residential portion of Kent and received an average precipitation of over 50 inches per year. During past periods of rainfall or snow melt, arsenic-contaminated sediments migrated as a result of stormwater runoff from elevated high concentration areas to lower lying areas. These lower lying areas are the additional residential properties being addressed under this Action Memorandum.

(4) The availability of other appropriate federal or State response mechanisms to

respond to the release [300.415(b)(2)(vii)]. No other federal or State response mechanism is available to timely address the threats

posed by the hazardous substances at the Site. IV. ENDANGERMENT DETERMINATION

Actual or threatened releases of hazardous substances from the Site may present an imminent and substantial endangerment to public health, or welfare, or the environment. V. EXEMPTION FROM STATUTORY LIMITS A. Consistency Exemption

The RV4 activities are consistent and appropriate with any future remedial action because they will not interfere with actions that will be needed to address long term threats presented by soil contamination and other potential environmental impacts in and around the Site. The RV4 activities are also appropriate in that they will reduce the direct contact threat to the property owners and occupants and reduce migration of contaminants from overland flow.

VI. PROPOSED ACTIONS AND ESTIMATED COSTS A. Proposed Actions 1. Proposed action description

The RV4 activities were initiated on April 8, 2019. The purpose of this removal action is to reduce the release or threat of release of arsenic in soil that could impact public health and the

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environment through direct contact, ingestion, and inhalation. EPA has begun implementing or plans to implement the following actions:

• Provide residential properties with measures to reduce migration of arsenic dust to the

interior of the residence; • Install physical barriers necessary to reduce direct contact and the migration of high levels

of arsenic in high use areas such as driveways, walkways and other areas frequented by the residents;

• Remove and replace impacted vegetable gardens; • Remove and replace ground cover in areas of elevated concentrations and by use of pets

and livestock; • As necessary and through consultation with risk assessors and health agencies, provide for

the cleaning of occupied interior space or provide measures to minimize exposures; • As necessary and through consultation with risk assessors and health agencies, perform

property maintenance activities or provide measures to minimize exposure; • Maintain all interim actions taken until the Remedial Program has mechanisms in place to

assume responsibility for these actions. Dispose off-Site any additional hazardous substances identified as impacting the public health during the course of the removal action;

• Provide for the disposal of waste generated while implementing this action at facilities that are in compliance with the EPA Off-Site Rule, 40 C.F.R. § 300.440;

• Continue to provide educational information to the impacted residents on how to reduce their potential exposures to arsenic contaminated soils; and

• Document all findings, actions taken, and any contaminated material left in place. 2. Contribution to remedial performance

The response measures documented in this Action Memorandum will address the immediate threat of exposure to arsenic from the Site. The action is consistent with the requirement of Section 104(a)(2) of CERCLA, 42 U.S.C. § 9604(a)(2), in that it will contribute to the efficient performance of any long-term remedial action with respect to the release or threatened release concerned. The planned removal action would be consistent with any future remedial action. Currently there are no long-term remedial actions planned for the Site, although the Site has been proposed for inclusion on the NPL and will be

evaluated as such. 3. Applicable or Relevant and Appropriate Requirements (“ARARs”)

ARARs within the scope of this removal action will be met to the extent practicable. Other ARARs from New York State may be forthcoming in response to a request for ARARs from EPA to NYSDEC via letter.

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4. Project schedule

Field activities were initiated on April 8, 2019. The majority of the remaining removal activities are expected to take approximately one month to complete, while some vegetative measures will need to be checked before the next growing season (greater than 12 months). This schedule is contingent upon weather conditions, availability of disposal facilities in compliance with the EPA Off-Site Rule, and un-interrupted Site access. The 12-month exemption is requested because of additional time that will be necessary to complete and maintain actions described within this Action Memorandum.

B. Estimated Costs The estimated costs for the completion of this project are summarized below. A confidential independent government cost estimate is included as Attachment D.

Direct Extramural Costs Previous Ceilings (“RV1-RV3”)

Funding Verbally Authorized on April 1, 2019 for RV4

Funding Requested in this Action Memorandum (“RV4”)

Revised Total Project Ceiling

Regional Allowance Costs (Total clean-up contractor including labor, equipment, materials, 20% contingency)

$220,220 $200,000 $258,000 $678,220

Total RST 3/START Costs $79,780 $0 $75,000 $154,780

Subtotal, Extramural Costs $300,000 $200,000 $333,000 $833,000

Extramural Contingency 20% (Rounded) $0 $0 $67,000 $67,000

Total Direct Extramural Costs $300,000 $200,000 $400,000 $900,000

VII. EXPECTED CHANGE IN THE SITUATION SHOULD ACTION BE DELAYED

OR NOT TAKEN If the proposed actions described in this memorandum are not implemented, the threats at the Site posed to human health and the environment by arsenic will persist, and residents will continue to come into direct contact with arsenic contaminated soil, which will increase their risk of arsenic exposure.

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VIII. OUTSTANDING POLICY ISSUES There are no known outstanding policy issues associated with the Site at the present time. IX. ENFORCEMENT This removal action was federally funded because no viable Potentially Responsible Party (“PRP”) has been identified, to date. EPA’s investigations into any viable PRPs remain ongoing.

ENFORCEMENT COST ESTIMATE The total cost for this removal action, based on full-cost accounting practices that will be eligible for cost recovery, is estimated to be $1,404,975 and was calculated as follows:

COST CATEGORY AMOUNT Direct Extramural Cost $900,000 Direct Intramural (RV4) Costs $75,000 Subtotal Direct Costs $975,000 Indirect Costs (Indirect Regional Cost Rate 44.10%) $429,975 Estimated EPA Costs Eligible for Cost Recovery $1,404,975 Note: 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 costs from this estimate will affect the United States’ right to cost recovery. X. RECOMMENDATION This decision document represents the selected removal action for the Arsenic Mine Site located in the Town of Kent, Putnam County, New York. This document has been developed in accordance with CERCLA, as amended, and is not inconsistent with the NCP. This decision is based on the administrative record for this decision document.

Conditions at the Site meet the criteria for CERCLA Section 104(c), 42 U.S.C. § 9604(c), consistency exemption, and I recommend your approval of the proposed removal action, ceiling increase, and waiver of the 12-month limitation. The total project ceiling approved for the RV1, RV2 and RV3 activities was $300,000, of which $220,220 was for mitigation contracting. On April 1, 2019, the verbal authorization provided a $200,000 increase to the total project ceiling. This memorandum requests an additional $400,000 total project ceiling increase, of which $258,000 is for mitigation contracting. The proposed new total project ceiling, if approved, will be $900,000, of which $678,220 is for mitigation contracting. There are sufficient funds available in the FY-19 Advice of Allowance to complete this response action.

Please indicate your formal approval of the confirmation of verbal funding authorization, ceilingincrease, and the 12-month exemption for the emergency CERCLA removal action at theArsenic Mine Site, as Delegation of Authority, by signing below.

Date: c?~Approved:Pat Evangelist ,Acting DirectorSuperfund and Emergency Management Division

Disapproved: Date:-------

Pat Evangelista, Acting DirectorSuperfund and Emergency Management Division

cc: (upon approval)P. Evangelista, SEMD-ADJ. Prince, SEMD-DDJ. Rotola, SEMD-RABD. Gaughan, SEMD-RABB. Grealish, SEMD-RABD. Garbarini, SEMD-NYRBM. Granger, SEMD-NYRBT. Lieber, ORC-NYCSFBJ. Doyle, ORC-NYCSFBA. Leshak, ORC-NYCSFBM. Mears, PADC. Echols, PADT. Grier, 5104AB. Schlieger, 5104AH. Freeman, OPM-GCMBL. Graziano, ATSDRP. McKechnie, OIGT. Benton, RSTG. Heitzman, NYSDECK. Carpenter, NYSDECK. Thompson, NYSDECA. Raddant, USDOI

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