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Subpart X Permit Writers Technical Resource Document

On December 10, 1987, EPA issued regulations that outlined procedures for issuing permits to miscellaneous units that treat, store, or dispose of hazardous waste. Those regulations, which were codified at title 40 of the Code of Federal Regulations (CFR) part 264, subpart X, created a new category of hazardous waste management unit (known as the miscellaneous unit or subpart X unit). Such units were defined as those that do not meet any of the definitions in part 264 of other types of hazardous waste management units. The purpose of this document is to provide EPA and State permit writers with guidance for reviewing permit applications and establishing permit conditions for Subpart X units.

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