Laserfiche WebLink
GEOMATRIX <br /> ORC REPLACEMENT ESTIMATE <br /> Based on the information provided by the ORC vendor Regenesis Bioremediation Products <br /> (Regenesis), each 2-inch diameter ORC sock weights 1.0 pound, contains 75 percent ORC, <br /> and ORC contains 10 percent of oxygen. For estimating the cost for Alternative 3, we <br /> assumed that 10 socks would be placed across the screened interval in each of wells MW-6, <br /> MW-7, MW-8, and MW-12. Using this information, 10 ORC socks in each well would sup- <br /> ply 0.75 pound of oxygen. The frequency of ORC replacement was estimated using this in- <br /> formation and the previous estimates of oxygen demand. As shown below, it was estimated <br /> that the frequency of ORC change out would range from 3 to 5 times per year. <br /> Estimated Frequency of <br /> Well ORC Replacement per year <br /> MW-6 5.1 <br /> MW-7 4.9 <br /> MW-8 1.7 <br /> MW-12 2.9 <br /> The frequency of ORC replacement is anticipated to become less as the petroleum concentra- <br /> tions in the wells decline with time. Therefore, it was conservatively(from a cost estimation <br /> standpoint) that an average of an average of three ORC change outs per year would be re- <br /> quired for the estimated remediation duration of 15 years for Alternative 3. <br /> \\oakI\deptdata\Doc_Safe\2000s\C2463\2463 resp RWQCB App A.doc A-2 <br />