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Site Number: |
A6R3 |
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Contract Number: |
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D.O. Number: |
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Action Memo Date: |
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Response Authority: |
CERCLA |
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Response Type: |
PRP Oversight |
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Response Lead: |
PRP |
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Incident Category: |
Removal Action |
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NPL Status: |
Non NPL |
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Operable Unit: |
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Mobilization Date: |
10/6/2015 |
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Start Date: |
10/7/2015 |
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Demob Date: |
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Completion Date: |
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CERCLIS ID: |
ARN000607042 |
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RCRIS ID: |
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ERNS No.: |
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State Notification: |
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FPN#: |
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Reimbursable Account #: |
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1.1.1 Incident Category
Time Critical Removal Action - RP-lead
1.1.2 Site Description
The North Little Rock Auto Salvage site is located at 600 Dixie Street in North Little Rock, Arkansas.This site was a former vermiculite exfoliation facility which was operated by the W.R. Grace Corp. from 1966 to 1986. This Site was assessed by EPA region 6 in multiple phases over the period of 2011 to 2013, as part of an Agency-wide initiative to investigate current and former vermiculite facilities. This site received approximately 85,000 tons of vermiculite ore from the W.R. Grace vermiculite mine in Libby, Montana. As a result of soil sampling conducted by EPA in July 2012, as well as Activity-Based Sampling (ABS) conducted in June 2013, several residential properties (i.e., "Lots") located along Dixie Lane were determined to contain levels of asbestos requiring removal. This includes various portions of Lot 9 (commercial) and the front yards of (residential) Lots 40, 42 and 55. Following negotiations with W.R. Grace, and an executed Administrative Order on Consent (AOC), W.R. Grace agreed to conduct additional ABS in the backyards of Lots 40. 42 and 55 and to remove soil from the impacted properties, followed by confirmation soil sampling, additional ABS and site restoration. This removal work in the residential area south of the former exfoliation site is referred to as Phase 1 under the AOC. Additional onsite removal work (on and around the former exfoliation facility) will be conducted by W.R. Grace, with EPA oversight, in phases 2 and 3 planned for later in 2015 and 2016.
1.1.2.1 Location
The four properties (i.e., "Lots") included in the Phase 1 Dixie Lane Removal Action are located directly south of the former exfoliation facility located at 600 Dixie Lane, in North Little Rock, Pulaski County, AR.
1.1.2.2 Description of Threat
As a result of the soil sampling and ABS sampling conducted by EPA along Dixie Lane, the properties included in the Phase 1 Dixie Lane Removal Action were impacted by asbestos either in soils at levels at or above 0.25% or in air samples at levels at or above target screening levels of 0.002 structures per cubic centimeter (s/cc) for residential properties (Lots 40, 42 and 55) or 0.001 s/cc for commercial properties (Lot 9). The target screening levels were generated through a site-specific risk assessment completed by EPA.
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2.1.1 Narrative
2.1.2 Response Actions to Date
The Consultant to the Responsible Party (RP), O'Reilly, Talbot and Okun (OTO), along with the EPA and START mobilized to the site on October 6, 2015. In an effort to determine whether additional soil removal would be required, OTO conducted additional ABS in the backyards of the residences at Lot 40, 42 and 55. The ABS consisted of a 2-hour "Raking" scenario and a 2-hour "Childs Play" scenario. During the ABS, air samples were collected from cassettes placed on personnel performing the activity, as well as upwind, downwind and background locations, and analyzed for asbestos by ISO 10312. For all scenarios and lot locations, the results did not indicate the presence of asbestos at levels requiring removal.
Following the backyard ABS activity, OTO initiated excavation of 12 inches of soil at Lot 55, followed by Lot 42, Lot 9 West, Lot 40 and Lot 9 East (South and North). The excavations at the residential Lots (40, 42 and 55) primarily encompassed the portion of the Lot in front of the residence along Dixie Lane. The exception was Lot 40, where the excavation area encircled the residence. Following completion at each of the Lots, OTO conducted two, 2-hour ABS scenarios (i.e., "Raking" and "Childs Play") within the base of the excavation at 12 inches bgs. During the ABS, air samples were collected from cassettes placed on personnel performing the activity, as well as upwind, downwind and background locations, and analyzed for asbestos by ISO 10312. For Lots 40, 42 and 55, asbestos was not detected during ABS at levels requiring additional excavation, and the excavation areas were backfilled with certified clean soil to original grade, followed by placement of sod and restoration of landscaping.
For Lot 9 West, confirmation air samples at the bottom of the 12 inch excavation showed asbestos in soil at levels above the industrial action level of 0.001 s/cc. As a result, OTO continued the excavation and removed an additional 6 inches of soil, resulting in a total excavation of 18 inches bgs. Following completion of the additional 6 inch excavation, OTO conducted two, 2-hour ABS scenarios (i.e., "Raking" and "Childs Play") within the base of the excavation at 12 inches bgs. During the ABS, air samples were collected from cassettes placed on personnel performing the activity, as well as upwind, downwind and background locations, and analyzed for asbestos by ISO 10312. Results from this second round of post-excavation ABS sampling did not detect any asbestos at levels requiring additional excavation, and the excavation areas were backfilled with certified clean soil to original grade, followed by placement of sod and restoration of landscaping.
Following the initial (to 12 inch bgs) Lot 9 West excavation, the North Little Rock area experienced a rain event which resulted in accumulation of a modest volume (approximately 8,000 gallons) of rainwater within the excavation are of Lot 9 West. Due to the nature of the area and potential for this accumulated storm water to come into contact with asbestos impacted soil, the storm water was pumped into a temporary storage tank to allow for the conduct of the excavation of an additional 6 inches of soil. This storm water was sampled and the results did not indicate the presence of any contamination, however the RP still directed OTO to dispose of the storm water at a controlled facility. As a result, the storm water was filtered with a 0.5 micron filter and pumped into vacuum trucks for disposal at a West Memphis, AR water treatment facility.
In an effort to restore the properties at or close to their original condition, OTO arranged for placement of gravel (for driveways) and backfill to the original grade, The top of the backfill was prepared with a soil amendment prior to placement of Sod in Lots 40, 42 and 55, seed and straw in Lot 9 West and no topping in the eastern portion of Lot 9 East. Where appropriate, additional landscaping treatments (i.e., plants and shrubs) comparable to those removed were planted. Following completion of the restoration of all Lots, OTO conducted general housekeeping activities along Dixie Lane.
All contract personnel demobilized from the Phase 1 site activities on November 7, 2015.
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