ARCHIVED REPORTS_XR0009512 - Laserfiche WebLink

Home Browse Search

F _ BTEX & TPH-G in MW-2; levels were lower than first recorded. 12-1 & MW-3 still below detection levels as shown on TABLE I . Gradient is still to the north. SE9 tember 1994 - Second quarterly monitoring measured continued lower levels of BTEX; however, TPH-G had increased significantly. MW-1 & MW73 still below detection limits. Hydraulic gradient has shifted about 40 degrees to the northeast. DETAILS OF LATEST WORK DONE: On December 19, 1994, personel from Jim Thorpe Oil, Inc. arrived on site at 0900 hours, and began cutting concrete in the area proposed for soil excavation. Because of restricted work space, the concrete was placed in a dump truck by the backhoe as it was removed. The final size of the area from which the concrete was removed measured 19' x 191 . Wm. Hunter, RG from Wm. J_ Hunter & Associates, (WJH, ) arrived at 1045 hours to supervise operations. After removing the concrete the backhoe began removing soil from the west end of the hole; some minor contamination was noted below 9' on the west & south walls. The soil was primarily a sandy clay with lenses of harder clay; no distinct bedding was noted. Removed spoil was stored on the concrete adjacent to the hole, and then was moved with the backhoe into the empty building immediately to the south of the excavation. Due to darkness, work was stopped at 1630 hours. The fence was replaced, and the removed spoil which had not been placed in the empty building was covered with plastic. On December 20, work began at 0830 hours; Jim Thorpe Oil personel began transferring the removed soil into the adjacent building to allow room for further excavation. The material had a strong Petroleum odor, and there were portions which had visible discoloration. The backhoe was relocated to the north side of the site, and began removing soil from the southwest & west side. Groundwater began to slowly enter the hole; it was measured at about 16'below grade before being covered with soil from the side of the hole. Excavation continued as directed by Mr. Hunter; sediments were a mix of sandy clays, silty clays, silts, & very silty, clayey sands_ As expected, contamination appeared to be stronger in the more permeable portions. Removed soil was placed on the concrete adjacent to the work site, and then moved by the. backhoe into the empty building next to the excavation. Because of the possibility of structural damage, it was not considered wise to excavate beneath the building on the south. . Space constraints prevented the backhoe from cleaning up the 3