WORK PLANS - Laserfiche WebLink

Home Browse Search

Following sampling on April 22, 1997,additional soil was removed to depths ranging from 1 to 3 '/2 feet. Soil was then sampled on April 25, 1998 at four locations within the excavated area, (Figure 2)and analyzed for TEPH as hydraulic oil. Results indicated that hydraulic oil was detected at 5,800 mg/kg at a depth of 3 Meet below surface grade at one location nearest the wellhead. Of the three other locations, one contained hydraulic oil at 120 mg/kg and two did not contain hydraulic oil at detectable levels. Further excavation and sampling activities were focused on the location near the wellhead which contained the highest level of hydraulic oil. Results of soil samples are listed in Table 2. On June 11, 1997,soil samples were collected using an Extended Soil Probe at depths ranging from 4 '/2 to 9 feet below surface grade and analyzed for TEPH as hydraulic oil. Hydraulic oil was detected at 4,900 mg/kg(4 '/2 to 5 feet)and at 390 mg/kg(8 '/2 to 9 feet)at location#1 (Figure 3), sample date June 11, 1997. Location#2 at 4 Meet was non detect for hydraulic oil. Results of soil samples are listed in Table 3. Groundwater was encountered at 9 Meet. Soil samples collected between October 21, 1997 to October 30, 1997, at 10, 11, and 12 feet contained 240, 140, and 100 mg/kg consecutively for hydraulic oil. A background sample of the native soil was taken on October 30, 1997 to aid in characterizing the peat dirt in the pit. The native soil resulted in 86 mg/kg as TEPH. Results of soil samples are listed in Table 3. Soil sampled on December 2, 1997,at 13 feet below the surface grade resulted in 65 mg/kg of hydraulic oil. Results for groundwater tested on the same date indicated that hydraulic oil was detected at 6.3 mg/l. Groundwater was removed from the excavation pit and placed in the facility's oil-water separator. Results of soil samples are listed in Table 3. In continuance of sampling on April 21, 1997,two samples were taken at 14 feet to confirm results of analysis for hydraulic oil,that being 450 mg/kg and 1700 mg/kg. Another sample at 15 feet resulted as 43 mg/kg, and two additional samples at 16 feet resulted as 1600mg/kg and 450 mg/kg(Figure 2), sample dates October 28, 1997 to April 28, 1998, show locations of samples taken. A silica-gel cleanup was performed in order to characterize interference from naturally occurring hydrocarbons present in native peat soils resulting in 900 mg/kg and 170 mg/kg. A standard run for TPH-oil resulted in 840 mg/kg and N.D. It is believed that during the period between December 2, 1997 and April 21, 19/97 rain flowed down the walls of the pit and created pockets of high concentrations of oil. Results of soil samples are listed in Table 4. 562 1-98 100.doc 4