Laserfiche WebLink
Mr George Takemori Project OF90-002 05 <br /> ! August 15, 1996 <br /> Page 5 <br /> the sort borings and soil samples collected from the limits of the excavation Analytical <br /> results are presented in Appendix C <br /> VI =3 14x(10ft)2x6ft= 1,884 ft3 <br /> Hydrocarbons remaining =720 mg/kg x i x 10'6 kg/mg x 1221b/ft3 x 1,884 ft3 <br /> = 165 lb of hydrocarbons remaining between 25 and 40 feet bgs <br /> Based on the analytical results of the soil samples collected from soil borings MW-9, MW-12, <br /> MW-13, and MW-14, residual hydrocarbons remain in soil beneath the UST excavation from <br /> 41 to 50 feet bgs TPHG was detected at a concentration of 6,200 ppm in boring MW-13 at a <br /> depth of 41 feet bgs Due to the absence of analytical data on soil samples collected <br /> laterally from soil boring MW-13, EMCON used the actual TPHG concentration detected <br /> in soil boring MW-13 and a conservative affected radius of 10 feet The total pounds of <br /> hydrocarbons remaining in soil from 41 to 50 feet bgs has been estimated using a concentration <br /> of 6,200 ppm, a bulk density of 122 lb/ft3, and assuming an affected radius of 10 feet <br /> • Analytical results are presented in Appendix C <br /> V2 = 3 14x (10ft)z x9ft=2,826 ft' <br /> Hydrocarbons remaining=6,200 mg/kg x 1 x 10-6 kg/mg x 122 lb/ft' x 2,826 ft' <br /> =2,138 Eb of hydrocarbons remaining between 42 and 50 feet bgs <br /> Based on analytical results of soil samples collected from soil boring MW-14, residual <br /> hydrocarbons remain in the soil beneath the central portion of the UST excavation from 51 to <br /> 65 feet bgs TPHG was detected at a concentration of 1,400 ppm at a depth of 55 feet bgs <br /> Due to the absence of analytical data on soil within the immediate vicinity of soil boring <br /> MW-14, EMCON used the actual TPHG concentration and a conservative affected radius <br /> of 10 feet The total pounds of hydrocarbons remaining in soil from 51 to 65 feet bgs has been <br /> estimated using a concentration of 1,400 ppm, assuming a bulk density of 145 lb/ft', and <br /> assuming an affected radius of 10 feet Analytical results are presented in Appendix C <br /> V3 =3 14x (10ft)2x 14ft = 4,396 ft' <br /> Hydrocarbons remaining= 1,400 mg/kg x 1 x 10-6 kg/mg x 145 lb/ft' x 4,396 ft3 <br /> =892 lb of hydrocarbons remaining between 51 and 65 feet bgs <br /> SAON\PJftF9MF9OW20SAS 95Spm 1 <br />