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f 3; e*cavat ion and that the SJLHD be r.ot i f ied in t irnc to Zvi mess a I 1 sampling. Af ter Nva i t ing tint i ! February , 1989 , cxcavat ion was carrrnenced without DHS approvai , althoul;h thev were notified that such activities were going to CtSrrtnen(_e. The i�e.c. 9 , 1955 proposal was never approved by the DHS, pres;:mcabIV owing to the fact that " 1e have found the plan inadequafeer.rifir-aIIv addressuorfl� definec, tIle as ttie work plan does not - p lateral and vertical extent of soi ! and/or groundwater contamina- tion. " , quotcd from Appendix A- ! 1 , %lay, 1959. It would seem that a proposed additional 5 , 335 cu. ft . of sail removal at the site of contamination, which encompassed an area from the surface to the groundwater vertically and horizontally to surrounding moni - toring wells , which had tested clean, could be presumed to remove all contarninated material , not just define extent . However , the proposal did not include the use of either a registerd geologist or engineer as is required by County and Tri-Regional guidelines . Based on the above premise, that all contaminated soil could be removed, the DHS was informed that owing to many considerations , including safety, protection of the groundwater from on through the open pit that still had contaminated soil in it and time considerations , JTO was going ahead with excavation. During February, 1959 the pit was dug to its approximate size today, about 160 ' to 150' across at the outer perimeter and 4 1 delep;4 ) t was later refilled to about 30 ' , its current depth Access ramps and erosion gulleys extend farther OUT. eoriginal dug depth of about 45' below ground level (9- 1 . ) , put bottom of the pit well into the ground water table, which had been found t at about -3S to -40 ft g. l . by GTI . (Apendix A-7) . During exca- vation, he sides were cut with lifts ( terraces) to help prevent caving of the sidewalls , leaving the bottom of the pit about 10' to 60' smaller than the top periphery. The total spoil removed now totaled about 15,000 cu. yds. %li clean spoil '-Vas placed on plastic sheeting over asphalt in file # 3 , contaminated spoil was placed either in Pile ,1 1 or Pile # 2 , also over plastic sheeting lying either on asphalt paving or concrete slabs . Segregation was achieved by a combination of visual inspect-i-on and odor . JTO re- ported that water did not immediately ediaely enter the hale when digging below the -39' groundwater level . A ckayey sand was penetrated at about -40g. l . , at the south end o{'the excavation and ground- water entered the hole thereafter . This clayey sand was logged in The GTI boring ,f 5 . Water gradually filled the excavation to a 10' seep at the south end of the excavation depth of about - 35' , (See Appendix 14 map) . The level of the water was measured by a surveyor and JTO from the top of the asphalt surface at the top of the entrance ramp, about 50' above mean sea level . This would put the standing water level about 5 ' higher than either County !eve_1 s mea s u r ed in t h e ---- - Control-records - {Fi 5 _, or- _ -F3 ood 5•-- _ - - - - monitoring wells . The -35' g • 1 . elevation was taken in Aper,,_ 1959, at a time when there had not been any recent rainfall . The 4