Laserfiche WebLink
URS <br /> Mr. Robert McClellon <br /> October 22, 2004 <br /> Page 4 <br /> 27 CCR 20919.5 Explosive Gas Control: <br /> (a) Owners or operators of all municipal solid waste landfill <br /> (MSWLF) units must ensure that: <br /> (1) The concentration of methane gas generated by the facility <br /> does not exceed 25 percent of the lower explosive limit <br /> (LEL)for methane in facility structures (excluding gas <br /> control or recovery system components); and <br /> (2) The concentration of methane gas does not exceed the <br /> LEL for methane at the facility property boundary. <br /> (c) If methane gas levels exceeding the limits specified in(a)are <br /> detected, the owner or operator must: <br /> (1) Immediately take all necessary steps to ensure protection <br /> of human health and notify the local enforcement agency <br /> (LEA). <br /> (2) Within seven days of detection,place in the operating <br /> record the methane gas level detected and a description of <br /> the steps taken to protect human health. <br /> (3) Within 60 days of detection, implement a remediation <br /> plan for the methane gas releases,place a copy of the plan <br /> in the operating record, and notify the LEA that the plan <br /> has been implemented. The plan shall describe the nature <br /> and extent of the problem and the proposed remedy. <br /> (4) The LEA with concurrence by the CIWMB pursuant to 40 <br /> CFR 258.23(c)(4)may establish alternative schedules for <br /> demonstrating compliance with(c)(2)and(c)(3). <br /> REMOVAL ACTION OBJECTIVES <br /> The removal action objectives are to reduce the methane concentration along the property boundary to <br /> less than its lower explosive limit(5% by volume). <br /> ALTERNATIVES EVALUATION <br /> Remedial action alternatives for landfill gas control were identified, screened,and evaluated.Ten <br /> alternatives were identified. The alternative treatment methods, considered for use at the site,are <br /> identified and evaluated in Table 1. <br /> As shown in Table 1, several methane control alternatives were identified as potentially viable for <br /> reducing the methane concentrations in the soils along the northern site boundary to below the LEL. <br /> These remedial action alternatives could be divided into the following three categories: source removal <br /> (waste excavation),air injection, and venting(passive or active) with the use of wells or trenches. The <br /> following factors were used to select the recommended remedial alternative: <br /> K:\Wprocess\25532\WorldEnterprise\Remediation Plan\L.ettendoc <br />