In February 2009, EPA and CSX Transportation, Inc. (CSXT) entered into an agreement where CSXT would perform the remaining removal activities under EPA oversight. CSXT is prepared a Removal Action Work Plan (RAP) to address remaining contamination at the Site where total arsenic exceeds 160 ppm in soil. Additionally, CSXT is required to mitigate off-site discharge of stormwater to an extent where acute water quality criteria for arsenic, chromium, and copper are not exceeded. OSC Smith approved the RAP on 08/17/09.
(See POLREP Nos. 1-13 for details of EPA's Fund-Lead Removal Action for this Site).
CSXT and their contractors began the PRP-lead phase of the removal action on Aug. 17, 2009.
(See POLREP No. 14 for background on PRP-lead removal action)
Full-Scale stabilization of arsenic-contaminated soils began during the week of 09/14/09 after results from the pilot test passed the Toxicity Characteristic Leaching Procedure (TCLP) for arsenic and chromium.
From 09/14 through 11/10 over 3000 cubic yards (c.y.) of soils were treated. Areas which were treated were covered with layers of geotextile materials and crushed gravel.
During this period a total of 320 c.y. of F035 hazardous waste/debris were shipped offsite to the appropriate EQ facilities in Wayne MI for disposal/treatment.
The storm water conveyance ditch onsite was also scraped to remove loose sediments and approximately two inches of clay soils below. XRF screening was used to guide removal of clay. Soil and sediments were collected in a roll-off box, tested, and disposed of as non-hazardous waste.
On 11/10/09, CSXT's contractors demobilized the site, marking the completion of construction activities. The site is secured, fenced and marked with signage indicating the appropriate CSXT person to contact for additional information regarding the site.
CSXT will continue to monitor surface water conditions at the storm water outfall and a short distance downstream to evaluate for exceedances of acute surface water quality criteria for arsenic, chromium, and copper. The sampling event conducted on 12/03/09 revealed copper in surface water at 82 ug/l, which exceeds the hardness adjusted limit of 54 ug/l. The next scheduled surface water sampling event is planned for February 2010.
CSXT will apply for a restrictive covenant with KDEP to ensure that future land use is compatible with environmental conditions at the site.
Post-excavation samples of the storm water conveyance ditch subgrade revealed arsenic at a concentration of 418 mg/kg, which exceeds the limit of 160 mg/kg, as established in the Administrative Order on Consent. CSXT will prepare a technical memo to specify by what means they intend to address residual arsenic contamination in the stormwater ditch.
NOTE: "Costs to Date" and "Disposition of Wastes" Section of this Polrep are cumulative figures for the EPA-lead portion of this removal action only
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