CORRESPONDENCE_1993 - 1996 - Laserfiche WebLink

Home Browse Search

ORDER AMENDING WASTE DISCHARGE REQUIREMENTS -3- FOR 3_FOR MUNICIPAL SOLID WASTE LANDFILLS IT IS HEREBY ORDERED that the Dischargers listed in Attachment 1, and their agents, assigns, and successors, in order to meet the provisions of Division 7 of the California Water Code, and the regulations adopted thereunder, shall comply with the following: As of the Federal Deadline, discharges of waste to either an MSWLF that has not received wastes as of that date or to a lateral expansion of an MSWLF unit are prohibited, unless the discharge is to an area equipped with a containment system which meets requirements in B. Specifications, specified below. • As of the Federal Deadline, municipal solid waste shall be discharged to either (1) that portion of a waste management unit which received wastes prior to the Federal Deadline (i.e., that active portion of the waste management unit which is within the boundaries of the Existing Footprint), or (2) to an area equipped with a containment system which meets the additional requirements for both liners and leachate collection systems specified below. 2. All containment systems installed after the Federal Deadline shall either: (1) include a composite liner which consists of an upper synthetic flexible membrane component (SL) and a lower component of soil. The SL shall be at least 40 -mils thick (or at least 60 -mils thick if of high density polyethylene) and shall be installed in direct and uniform contact with the underlying compacted soil component. The lower component shall be compacted soil that is at least two feet thick and that has an hydraulic conductivity of no more than 1 x 10-' cm/sec (this specification is referred to as the Prescriptive Design); or (2) satisfy the performance criteria contained in 40 CFR 258.40(a)(1) and (c) and the criteria for an engineered alternative as provided by 23 CCR 2510(b), where the performance of the alternative containment system's components, in combination, equal or exceed the waste containment capability of the Prescriptive Design. 3. All containment systems installed prior to the Federal Deadline and which will accept wastes after the Federal Deadline shall include a composite liner which features as its uppermost component a synthetic liner (SL). The SL shall be at least 40 -mils thick (or at least 60 -mils thick if high density polyethylene) and shall be installed in direct and uniform contact with the underlying materials. The composite liner shall meet the performance criteria contained in 40 CFR 258.40(a)(1) and (c). For steep sideslopes (as defined in specification 4., below) the composite 40 mil (60 mil if HDPE) specification may be replaced by a non -composite 60 mil (80 mil if HDPE) specification. 4. Containment systems installed in those portions of an MSWLF where an engineering analysis shows that sideslopes are too steep to permit construction of a stable composite liner that meets the prescriptive standards contained in either B.2. or B.3., above shall include an alternative