The EPA removal action which was initiated in August 2005 and halted in January 2006 was re-started on June 1, 2006. The scope of work for Phase 2 activities involves construction of a cap and a sheet pile wall to isolate an area of high VOC contamination in soil (total VOCs in soil > 10,000 ppm), and to cutoff the offsite migration of contaminants discharging into a nearby storm drain. (See Previous POLREPs and the Action Memos approved for this Site for a more complete description of site background).
Above average rainfall in July 2006, and the discovery of additional areas of contamination necessitated authorization to continue the removal action beyond the one year statutory deadline. The Statutory Exemption Action Memo was signed in August 2006, authorizing additional removal activities to continue through September 2007, allowing for a response to any possible discoveries of contamination encountered during construction activities by the prospective purchaser for re-use of the Site. The U.S. District Court for the Eastern District of Kentucky has granted access to the Site to EPA and it's contractors during this period.
All site personnel and equipment were demobilized on October 5, 2006. All areas onsite (with the exception of the former railroad spur) were covered with geotextile, graded and seeded prior to demobilization. The chain link fence surrounding the Site was repaired and secured prior to demobilization. Completion of final capping and grading of the Site will resume, once the necessary upgrades to the SD1 system have been completed by the utility.
The following paragraphs contain a summary of highlights and other important findings observed during the reporting period:
EPA OSC Smith onsite on 08/03 to inspect the work, and to discuss issues including:
(1) options for capping the significant additional volumes of contaminated soil encountered during Phase 2 of the removal action, and;
(2) construction of the perimeter drainage system to re-route the surface and subsurface drainage running onto the site along the east property line.
OSC Smith approved a plan to double the size of the existing sheet pile cell, which will accommodate additional volumes of soil to be capped, and also serve as a barrier to subsurface water intrusion through the cap. This change necessitated an exemption to the 12 month statutory limit, and obligation of an additional $375,000 in ERRS funding. The Exemption Request Action Memo was approved on 08/18, and the ERRS ceiling increase was processed on 08/30.
Construction on the extension of the existing sheet pile cell began on 08/16, and was completed on 09/11. The sheet pile cell is about 17,000 sq. feet in area and contains over 1000 cy of contaminated soil. These soils were excavated from areas where contact with subsurface runoff resulted in leachate generation and subsequent discharge to the municipal sewer system. During the period when pile driving operations were conducted, deteriorated (and empty) metal drums were encountered at the north end of the site on the west side of the old receiving dock. These materials were disposed of as solid waste, and soils were excavated to a depth of 6 –7 feet, and placed into the cell for capping.
Construction of the perimeter drainage system was completed on 08/31. Over 480 linear feet of drainage system was installed along the eastern (upgradient) perimeter of the Site to intercept and control subsurface water flow. Prior to construction, all visibly discolored soils were removed down to the top of a continuous clay layer found at an average depth of 3' below land surface. The system operates as a french drain, and consists of 4" diameter perforated pipe bedded in gravel. The drain was joined to a 6" diameter PVC pipe which passes through the sheet pile cell and is connected to a foundation drain on the west side (downgradient) area of the Site.
Final placement of soils into the cell occurred on 09/19, and capping of the cell and all other areas where visibly contaminated soils appear at the surface was partially completed on 09/21. Construction was halted on 09/22, due to a significant rain event, which dropped over 3 inches of rain on the Site in a 48 hr. period.
On 10/4, the OSC and KYDEP met with the Sanitation District No. 1 (SD1) and received permission to tie in the perimeter drainage system to a sewer manhole onsite. Conditions for receiving approval to discharge into the SD1 system include quarterly monitoring of stormwater quality for a period of 1 year, ending in June 2007.
- connect perimeter drainage system to existing sewer manhole onsite.
- raise existing manholes and drop inlet rim elevations to allow for re-grading of the Site
- complete construction of clay cap within former railroad spur right of way, and tie into recently completed clay cap onsite.
- re-seed the newly graded areas to prevent soil erosion.
- construct a shallow and a deep monitoring well at the site perimeter in order to evaluate for potential contaminant migration offsite. EPA ERT's contractor issued an RFP on 10/20 for the construction of these wells.
EPA will prepare a "comfort letter" for the City of Ludlow, as a means of clarifying liability concerns for the prospective purchaser of the property, and to outline the future land use restrictions to be imposed.
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