As discussed in a memo EPA’s headquarters recently distributed to its regional offices, the Resource Conservation and Recovery Act’s (RCRA) land disposal restrictions (LDRs) do not distinguish between temporary and permanent placement of hazardous wastes in landfills.

Prohibited wastes may not for any duration be placed in landfills unless they meet the applicable treatment standards.  Containers located in or on a landfill are also considered land disposal.  However, RCRA does allow one exception to the prohibition, called the no-migration variance.

In the memo, the director of EPA’s Office of Resource Conservation and Recovery states:  “[I]n regards to the legality of disposing of prohibited wastes before verifying that the treatment standards are satisfied, if the wastes in fact meet the treatment standards, then the disposal is legal.  If the wastes do not meet the treatment standards, then the disposal is illegal—unless the disposal unit is an approved no-migration unit.”

Statutory basis

The no-migration variance is explicitly established under RCRA Sections 3004(d), (e), and (g)(5).  The sections state that a method of land disposal may not be determined to be protective of human health and the environment for a listed hazardous waste that has not met the treatment standards unless “upon application by an interested person, it has been demonstrated to the Administrator, to a reasonable degree of certainty, that there will be no migration of hazardous constituents from the disposal unit or injection zone for as long as the wastes remain hazardous.”

Variance petition

A no-migration variance allows land disposal of restricted wastes not meeting the LDR treatment standards in a specific unit (or engineered subunit within an area of contamination).  The EPA has a long-established process for granting no-migration variances.

Specifically, site managers must produce a demonstration that actual or predicted concentrations of hazardous constituents or emissions rates at the edge or boundary of the unit do not exceed health-based levels or environmentally protective levels for groundwater, surface water, soil, and air for as long as the waste remains hazardous.  Site managers also must ensure that monitoring of all environmental media, including groundwater, surface water, soil, and air, is or will be in place to demonstrate compliance.

No-migration scenarios

The EPA has identified several scenarios in which a no-migration variance would be appropriately granted:

• Placement of compatible nonvolatile wastes in a massive and stable geologic formation, such as a salt dome;
• Placement of a waste consisting of fairly immobile constituents in a monofill (i.e., a waste unit that contains only one hazardous waste) located in an arid area that has no groundwater recharge;
• Placement of a hazardous waste in a land-treatment facility that, through active chemical, physical, biological, or other processes, renders it nonhazardous; and
• Temporary storage of a hazardous waste in a totally enclosed indoor waste pile with a floor or bottom liner for a purpose other than to accumulate sufficient quantities of the waste to allow for proper recovery, treatment, or disposal.

Petition contents

Any petition requesting that the EPA grant a no-migration variance must include the following components (40 CFR 268.6(a)):

• Identification of the specific waste and the specific unit for which the demonstration will be made;
• A waste analysis to describe fully the chemical and physical characteristics of the subject waste;
• A comprehensive characterization of the disposal unit site, including an analysis of background air, soil, and water quality;
• A monitoring plan that detects migration at the earliest practicable time; and
• Sufficient information to assure the Agency that the owner or operator of a land disposal unit receiving restricted waste(s) will comply with other applicable federal, state, and local laws.

Criteria

Further, the demonstration must meet the following criteria (40 CFR 268(b)):

• All waste and environmental sampling, test, and analysis data must be accurate and reproducible to the extent that state-of-the-art techniques allow.
• All sampling, testing, and estimation techniques for chemical and physical properties of the waste and all environmental parameters must have been approved by the EPA.
• Simulation models must be calibrated for the specific waste and site conditions and verified for accuracy by comparison with actual measurements.
• A quality assurance and quality control plan that addresses all aspects of the demonstration must be approved by the EPA.
• An analysis must be performed to identify and quantify any aspects of the demonstration that contribute significantly to uncertainty. This analysis must include an evaluation of the consequences of predictable future events, including, but not limited to, earthquakes, floods, severe storm events, droughts, or other natural phenomena.

No-migration variances may also be appropriate in conjunction with Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) actions involving the injection of hazardous wastes into Class I injection wells.

For a Class I variance, petitioners must demonstrate that wastes do not migrate from the injection zone.

EPA guide