The SWP site is located at the corner of Miller Street and Covington Drive in Canton, Madison County, Mississippi in a predominantly commercial and residential area. Specifically, the geographic coordinates for the SWP site are 32.6180611 degrees north latitude and -90.0181889 degrees west longitude. The site covers approximately 20 acres and includes an abandoned wood preserving plant and a former lagoon waste treatment cell. The site is bounded to the north by Batchelor Creek and the Illinois Central Gulf Railroad, which is no longer in operation. The site is bounded to the east by an abandoned industrial area and to the west by residential properties. To the south, the site is bordered by Covington Drive, which extends from Miller Street in the west to Hargon Street in the east. The City of Canton operates a drinking water well field just south of Covington Drive.
Wood treating operations at the SWP site began in 1928 and ended around 1979, when the owner filed for bankruptcy. During operations, southern yellow pine timbers were debarked and placed in retort cylinders for drying. Hot creosote and pentachlorophenol were used as wood preservatives. Three on-site, unlined wastewater treatment surface impoundments were constructed for disposal of treatment sludges and process wastewater. During the 1970’s, the facility received several notices of violation and fines for gross contamination of the process area, releases of hazardous substances to Batchelor Creek, and inadequate treatment of process wastewater prior to discharge into the city sewage treatment facility. Prior to 1977, when the Clean Water Act was passed, the facility reportedly discharged approximately 50,000 gallons of wastewater directly into Batchelor Creek, which flows through a city park, a residential area, and downtown Canton before flowing into Bear Creek. When operations ceased, there were large areas of contamination in the treatment and storage areas. There were also piles of contaminated soil, creosote sludge storage tanks, and three unlined wastewater surface impoundments that had been filled by a previous owner at an unspecified time.
Based on analytical results for ground water, soil, and sediment samples collected from the site during previous investigations, further action at the SWP site was initiated by EPA to address contamination present in Batchelor Creek along the northern boundary of the site.
On August 25, 2009, the EPA Emergency and Rapid Response Services (ERRS) contractor WRScompass, Inc. (WRScompass) mobilized to the site. Site preparation activities consisted of clearing and grubbing the site of vegetation, construction of an access road to Batchelor Creek, and the construction of a temporary staging area to stockpile contaminated soils and sediments excavated from the creek. Other activities include the removal and segregation of riprap from the banks of Batchelor Creek and the establishment of a site office.
During site clearing and grubbing activities, WRScompass discovered two drums of used oil and one electrical transformer. The drums and transformer were staged near the site trailer and were sampled and profiled for disposal by WRScompass. On September 23, 2010, the drums and transformer were transported off site by The Environmental Quality Company for disposal.
WRScompass began excavation of contaminated soil and sediment from Batchelor Creek in September 2009. Water in the creek was controlled by using a pump system and earthen dams to divert the flow of water around the section of creek requiring excavation. Personnel used 6-inch and 8-inch pumps and approximately 2,200 linear feet of 12-inch polyvinyl chloride (PVC) pipe to divert the water around the area of excavation. During installation of drainage piping at the site, WRScompass encountered two underground storage tanks (USTs) near the south bank of the creek on November 3, 2009. The USTs were subsequently removed from the site and disposed off-site during creek excavation activities.
Contaminated soil and sediment excavated from Batchelor Creek were stockpiled at the SWP site in an area located to the west of the former lagoon waste treatment cell. During creek excavation activities, Tetra Tech START was tasked to periodically mobilize to the site and collect post-excavation soil samples from the bottom of the excavation for laboratory analysis. Tetra Tech START collected post-excavation samples on four separate dates: November 18, 2009, January 15, 2010, January 26, 2010, and March 11, 2010. A total of 12 post-excavation samples and one field duplicate sample were collected from 11 locations along the excavated bottom of Batchelor Creek, which extended for a distance of approximately 1,100 linear feet. Specifically, Tetra Tech START collected one (1) five-point composite sample for approximately every 100 linear feet of excavated creek bottom. The five aliquots for each composite sample were collected at depths ranging from 0 to 6 inches below the excavated ground surface.
Excavation activities along Batchelor Creek were completed in January 2010. WRScompass subsequently placed backfill in the areas of excavation to provide stability for the creek and prevent collapse. Following completion of excavation and backfill activities, WRScompass dismantled and removed the pump system used to divert the flow of water. PVC piping from the pump system was staged onsite. Tetra Tech START collected one wipe sample (SWP-Wipe-01) from the PVC pipe, which was submitted to the EPA CLP for laboratory analysis of TCL SVOCs. Additional information regarding all samples collected during the removal action can be found in the Final CERCLA Removal Action Report prepared for EPA by Tetra Tech EM Inc., dated March 14, 2011.
Following completion of excavation and backfill activities, WRScompass installed a slurry wall along the south bank of Batchelor Creek during February and March, 2010. The slurry wall consisted of a trench measuring approximately 1,500 feet long, three feet wide, and 30 feet deep. The slurry wall was excavated in sections, with each section backfilled with a cement and bentonite mixture. The mixture, or slurry, was generated on site utilizing a mixing plant assembled at the site by WRScompass, and was pumped into the trench through a four-inch, high density polyethylene (HDPE) pipe system. Slurry wall installation activities, including the dismantling and demobilization of related equipment, were completed by the end of March 2010.
Upon completion of excavation activities, the Batchelor Creek stockpile measured approximately 300 feet from east to west and 100 feet from north to south. On March 11, 2010, Tetra Tech START collected a total of five stockpile samples and one field duplicate sample from the Batchelor Creek stockpile. Specifically, Tetra Tech START divided the stockpile into grids, each measuring approximately 60 feet by 100 feet each, and collected one (1) three-point composite sample from each grid. Each aliquot was collected from near the bottom of the stockpile using heavy equipment operated by WRScompass to access the sampling locations. The following list provides a brief summary of the stockpile samples collected:
♦ SWP-SP-01 (east side of the Batchelor Creek stockpile);
♦ SWP-SP-01D (field duplicate sample of SWP-SP-01);
♦ SWP-SP-02 (east-central portion of the Batchelor Creek stockpile);
♦ SWP-SP-03 (center portion of the Batchelor Creek stockpile);
♦ SWP-SP-04 (west-central portion of the Batchelor Creek stockpile); and
♦ SWP-SP-05 (west side of the Batchelor Creek stockpile).
Stockpile samples were analyzed using the EPA CLP for the following parameters:
♦ TCL SVOCs;
♦ Toxicity Characteristic Leaching Procedure (TCLP) volatile organic compounds (VOC);
♦ TCLP SVOCs;
♦ TCLP pesticides and herbicides; and
♦ TCLP metals (including mercury).
On June 17, 2010, WRScompass mobilized to the site to conduct transportation and disposal activities for the Batchelor Creek stockpile. Road base and asphalt were placed at the site to facilitate the loading of trucks. During this time, Tetra Tech START mobilized to the site on three separate dates (August 17, August 31, and September 16, 2010) to document activities.
Stockpile disposal activities included the transportation and disposal of a total of 61,836.43 tons of soil from the Batchelor Creek stockpile, which were transported offsite for disposal at the Clearview Landfill located in Lake, Mississippi. This total includes soil removed from the footprint of the Batchelor Creek stockpile, which was conservatively excavated to a depth of approximately two feet below ground surface during loading activities to ensure the removal of contaminated materials. Stockpile disposal activities were completed on September 24, 2010.
Concurrent with stockpile disposal activities, WRScompass conducted site restoration activities in various areas of the SWP site. The activities are summarized below.
♦ Approximately two to three feet of clay were placed and graded for proper drainage over the site, including the area of the former Batchelor Creek stockpile area and areas used during historic wood treatment operations. Clean topsoil was subsequently placed over the clay-capped areas of the site and planted with grass seed for erosion control.
♦ Batchelor Creek restoration activities were conducted by Vinton, Inc. under subcontract to WRScompass along the approximately 1,100 linear feet of creek that were impacted by removal activities. Creek restoration activities were completed on September 13, 2010 and included:
o Grading and installation of erosion control fabric along the south bank of the creek.
o Installation of limestone rip rap on the north bank, south bank, and bottom of the creek.
o Installation of sod along the top of the south bank of the creek.
♦ Entrances to the site were blocked to prevent motorized vehicle entry.
Site restoration activities were completed on September 24, 2010. On November 30, 2010, WRScompass returned to the site to ensure grass and sod were growing and document final site conditions. This completed the removal action.
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