The Precision National Plating Site is located at 198 Ackerly Road, Clarks Summit, Pennsylvania, which is approximately 10 miles north of Scranton, Pennsylvania. The property measures 46 acres, approximately five acres of which were used for site operations and the remainder of which are undeveloped and largely wooded. A 45,000 square foot operations building was the principal structure on the site.
The site began operation as a chromium electroplating facility for locomotive crankshafts in 1956. This operation continued when Precision bought the facility in 1971. Precision operated an industrial component reconditioning facility on site from 1971 until 1999.
Site operations ceased in April 1999. With PADEP and USEPA oversight, the former plating building was demolished in the Fall of 2000.
EPA approved the Remedial Action Plan (RAP), submitted on behalf of Precision National Plating by the Retec Group in September of 2005. The RAP details plans to use calcium polysulfide to reduce the hexavalent chromium in the soils and groundwater to trivalent chromium.
In July 2006, Precision injected calcium polysulfide into source areas at the site to reduce hexavalent chromium to a relatively non-toxic form which will precipitate and remain in the soil matrix. The goal of the treatment was to reduce hexavalent chromium levels in soil to below 60 mg/Kg, and hexavalent chromium levels in Ackerly Creek to below 11 ug/L.
In March 2007, Precision began excavation of the basement of the former facility (see "Images"). The purpose of the removal was to mitigate impacts by potentially contaminated soils beneath the basement. Any contaminated concrete unearthed during the excavation was taken to an appropriate disposal facility.
Further site investigation activities were performed in the Fall of 2007 and February/March 2008. The soil boring, rock coring and groundwater sampling activities completed in October 2007 and March 2008 confirmed that residual contaminant sources remain at the Site in the weathered rock and shallow competent bedrock (18 - 30 feet below the ground surface).
In August 2008, in-situ chemical injections began using calcium polysulfide to treat these residual areas of contamination in the shallow bedrock. Chemical injections were completed on January 9th, 2009.
Hexavalent Chromium levels have dropped in Ackerly Creek due to chemical injection treatments in July 2006 and the basement excavation in March 2007, and subsequent injection activities beginning in August 2008 and continuing through the December 2010, however they still remain above the target ecological goal of 11 ug/L.
On Tuesday, October 11, 2011 Precision began the fourth round of injection activities at the site. This is the third round of injections into shallow bedrock. The current round of injections are scheduled to be completed in early December.
During the week of October 31st, a total of 1,097 gallons of 1% concentration calcium polysulfide, and a total of 9,110 gallons of 2% concentration solution was injected into a total of 5 wells. A total of 15,358 gallons of 1% and 12,832 gallons of 2% concentration calcium polysulfide has been injected into a total of 30 wells during this round of injections.
Air monitoring is being conducted for hydrogen sulfide every hour during injection activities along Arch Ave and the perimeter of the site from the time injections begin in the morning to one hour after injections are completed each day. Arcadis is continuously recording hydrogen sulfide values between the lagoon and the homes on Arch Avenue 24 hours a day. Hydrogen sulfide readings from hand held monitors ranged from non-detect to 7 parts per billion throughout the week at Arch Avenue and perimeter monitoring locations.
Arcadis has been preparing the injection system for colder temperatures installing insulation and heating materials on the portions of the system which handle liquids. Arcadis is also conducting general maintenance on the system during injection activities.
PADEP and EPA representatives were onsite throughout the week conducting oversight of ongoing injection activities.
Injections of calcium polysulfide are currently scheduled to be completed in December 2011.
Perimeter air monitoring will continue around the injection site with the use of the remote monitors (continuously) and hand held units (every hour) during injection activities by EPA and Precision contractors, and will continue for one week after the injections have ceased.
Results from the sampling activities conducted in September 2011, are expected to be received in November 2011.
Calcium Polysulfide injections are scheduled to begin into three newly installed wells in the near future: MW13-S, OMW 21, OMW 22.
EPA will be meeting with the township the week of November 14th regarding ongoing activities at the site.