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Calculating EHS quantities within landfills

How are the quantities of the extremely hazardous substances (EHSs) to be calculated in determining if landfills are subject to the section 302 requirements?

EPA realizes the practical problems presented for landfills in complying with the Title III requirements.  Owners of these facilities must determine, based on reasonably available information whether any EHSs are in excess of the threshold planning quantities (TPQ).  However, in making such a determination, owners and operators of landfills should apply the one percent (1%) exclusion (see 40 CFR 355.13).  EPA believes that the one percent (1%) exclusion is applicable to the contents of the entire landfill based on the assumption that such containers will degrade in the landfill environment.

Therefore, if the total weight of an extremely hazardous substance is greater than one percent (1%) of the total weight of the landfill waste and equals or exceeds the threshold planning quantity for that substance, the landfill is subject to Section §302 notification requirements.  If no extremely hazardous substance exceeds this level, the landfill is not subject to emergency planning requirements under Title III unless designated by the Governor or State Emergency Response Commission under Section 302(b)(2).

Following any resulting notification to the State Commission and designation of a facility emergency coordinator (Section 303(d)(1)) the local committee may, depending on their site specific assessment of the hazards posed by the particular facility, request participation of the facility in the Title III planning process.  Even though many landfills may not be required to provide planning notification based on the one percent (1%) exclusion cited above, the landfill owner/operator and the local emergency planning committee should work cooperatively to ensure that potential chemical emergencies are addressed.