Laserfiche WebLink
2.1.1 VAPOR EXTRACTION <br /> • Initiation of a vapor extraction system at the site would include the installation of one or <br /> more extraction wells and a vapor unit. The cost for the <br /> drilling,st for equipment renation and pt.al� <br /> the system would be approximately $15,00(1 to $20,000 r month However, with <br /> maintenance and supplementary fuel could cost up to $7,500 per <br /> such low concentrations of hydrocarbons in the soil it its unlikely that vapor extraction would <br /> effectively reduce existing hydrocarbon concentrations. <br /> 2.1.2 EXCAVATION <br /> ining <br /> Additional excavation of impacted soil at the <br /> excess of 40 feetremove , excavation may not HHowever, because the impacted soil is at depths in <br /> logistically possible. <br /> Approximately 5,000 cubic yards of overburden or "clean" soil would have to be removed <br /> to excavated the remaining 127 cubic yards Additional cost incurred for the removal of the <br /> overburden and impacted soils would be approximately $30,of tee�xcavo $40,000 a bCossts for <br /> great <br /> treatment or disposal of the impacted sail and b g <br /> as $20,000 to $30,000 <br /> soil <br /> as been <br /> from the <br /> Considering that greater than 90 percent °f the ddit nalcoct of as mu h as $70,OOOao removesite at a cost of approximately $140,000, an a <br /> the remaining 10 percent would not be justified Furthermore, the remaining impacted soil <br />• has an average hydrocarbon concentration of only 4 38 parts per million <br /> 3.0 CONCLUSIONS <br /> Approximately 127 cubic yards of hydrocarbon impacted soil remains at the site. The <br /> remaining impacted soil has an average concentration ons Furthennorea the remainingrts per the total <br /> impacted <br /> volume of remaining hydrocarbons is 0 22 gallons <br /> soil is approximately 15 to 20 feet from current groundwater <br /> Based upon soil samples collected from the stockpiled soil from the excavation in October <br /> 1993 (Appendix C of the Quarterly Report - January 1994), the verage oca bon release concentration o <br /> hydrocarbons was 194 parts per million The original volume of they <br /> an <br /> then be calculated to be approximately sed" hydrocarbons havens ed upon these been successfully removed <br /> approximately 99 8 percent of the r <br /> from the property <br /> It should be noted that calculations of the remaining volume of hydrocarbons are based <br /> upon soil samples collected two to threeyears go, it is likely athe o natural ign fic ntly degradation <br /> processes have decreased the volume of remaining hydrocarbons n <br /> 2 <br /> i r <br /> z <br />