Remedial Investigation/recommended action-1995

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� Sailors World, Inc. Summit Project No. 922030 - � October 5, 1995 Page 4 � method. Generally, soil vapor headspace readings decreased with depth, indicating the majority of petroleum hydrocarbon impacted soil was present in the upper 4 to 5 feet of soil. � The excavation was limited in a southeasterly direction because of the presence of underground utilities (Figure 2). Subsequently, three hand auger borings were completed in an area southeast � of the excavation. Results of soil headspace screening at these locations indicated soil in this area was impacted with petroleum hydrocarbons. PID readings at these locations ranged from 66 to 150 ,ppm. Observations recorded during the excavation activities and related laboratory � , analytical results are included in the attached excavation report(Appendix II). Impacted soil was transported in May 1993 to C.S. McCrossan, located in Maple Grove, � Minnesota. A total of 130 cubic yards of impacted soil were thermally treated: 60 cubic yazds previously removed by Foth & Van Dyke and 70 cubic yards removed under the observation of Summit. � 3.2 Test Probes and Site Geology � On June 15, 1994, eight Geoprobem test probes, P-1 through P-8, were completed and groundwater samples were collected. Water was not observed at P-7, which was completed to a � depth of 10 below the ground surface. Probe depths ranged from 5 to 10 feet deep and probe locations aze illustrated on Figure 2. � An additional seven Geoprobe� test probes (labeled P-9 through P-15 on Figure 2) were completed on 7une 2, 1995. Four of these test probes were completed on the property owned by Sailors World and three probes were completed on the right-of-way of Counry Road 15. A � Macro-Corem 4-foot long sampling system was utilized to collect soil cores at these test probe locations. Variable soil types were encountered and soil descriptions included silty clay, sand, silty sand, and gravel. Much of the soil that was observed may be fill, as indicated by an asphalt � layer that was encountered at approximately 4 feet below the ground surface at test probe location P-11. Wet soil was encountered at depths ranging from 1.5 to 5 feet below grade. Observations at several test probe locations indicated that the soil was not consistently � "saturated" or wet at depth. "Dry" soil, or soil that appeared to be below saturation, was observed underlying coarser, wet soil at P-9, P-11, P-12, and P-14. Several probes were completed near previous probe locations to evaluate movement of hydrocarbons in the subsurface during the past � year. Probe P-15 was completed in the former UST basin, between the previous probe location that showed the highest benzene concentrations (P-3) and the probable groundwater discharge � area(Lake Minnetonka). Geoprobe�test probe logs that contain soil descriptions are included in Appendix III. � . ' �