Introduction

The U.S. Environmental Protection Agency (USEPA) issued the proposed HWIR that will exempt certain low risk, listed hazardous wastes from regulation under Subtitle C of the Resource Conservation and Recovery Act (RCRA). The proposed rule applies to listed hazardous wastes, mixtures of listed hazardous wastes and solid waste, and residues derived from the treatment, storage, or disposal of listed hazardous wastes.

The proposed rule establishes risk-based concentration levels for specific constituents, called exit levels, that must be met before a waste may be exempt from regulation as a hazardous waste. Listed waste that exhibits any characteristic, however, will continue to be regulated as a hazardous waste until the characteristic is removed. Generators who wish to claim a waste as exempt must follow a specific exemption process.

The final version of the rule will be applicable in states without RCRA delegation; RCRA authorized states are not required to adopt consistent regulations.

Key Features:

	Sets Subtitle C exit levels for 376 constituents.
	Designed to be self-implementing.
	Specifies exemption requirements for sampling, analysis, reporting, record- keeping, and public participation; failure to meet these requirements voids the proposed exemptions.
	Sets different risk-based exit levels for waste waters and non-waste waters.
	Requests comments on five conditional management options that could result in higher exit level concentrations.
	Based on a new multi-pathway risk analysis that includes direct and indirect potential exposures via ground water, surface water, air, and soil.
	Encourages pollution prevention to avoid Subtitle C.
	Provides incentive to develop innovative treatment technologies.

Application

	Facilities generating or managing listed wastes with consistently low RCRA constituent concentrations.
	Facilities with available Subtitle D disposal facilities may be able to achieve contingent management.
	TSD facilities may have to amend their waste analysis plans; permitted facilities in unauthorized states should submit a Class I permit modification.
	Units receiving only newly exempted wastes could trigger closure requirements.
	By definition, wastes meeting the exit criteria at the point of generation are not subject to Land Disposal Restrictions (LDRs).
	The proposed exit levels for volatile organic compounds (VOCs) are deemed protective of the environment even where they exceed current RCRA air emission standards.
	CERCLA release notification of wastes exempted under the rule may no longer be necessary.
	Federal RCRA management requirements may no longer be applicable as CERCLA Applicable or Relevant and Appropriate Requirements (ARARs).
	The exemption applies to hazardous debris and media with constituent concentrations below the exit levels. However, USEPA or authorized states may still make site-specific determinations of whether media "contains" a RCRA hazardous waste when concentrations are higher or lower than the proposed exit levels. (The upcoming contaminated media rule will include a "bright line", which will define when hazardous contaminated media will be subject to a modified Subtitle C or more site-specific standards to be implemented by the states.)