Landfills used specifically for the disposal of hazardous waste. These landfills are not used for the disposal of solid waste.
Summary of Federal Requirements
In terms of hazardous waste, a landfill is defined as a disposal facility or part of a facility where hazardous waste is placed in or on land and which is not a pile, a land treatment facility, a surface impoundment, an underground injection well, a salt dome formation, a salt bed formation, an underground mine, a cave, or a corrective action management unit (40 CFR 260.10).
An hazardous waste landfill is a treatment, storage, and disposal facility (TSDF) and as such must be appropriately permitted and the permit will specify all design and operating practices necessary to ensure compliance.
All hazardous waste landfills are required to have a run-on control system, a runoff management system, and control the wind dispersal of particulate matter.
The run-on control system must have the capacity to prevent flow onto the active portion of the landfill during peak discharge of a 25-yr storm and the runoff management system must have an adequate capacity to collect and control water from a 24-h, 25-yr storm and the contents tested to determine correct disposal methodology.
The collection and holding tanks or basins for run-on and runoff control systems must be emptied expeditiously after storms.
For each hazardous waste landfill there must be a map with the exact location and dimensions, including depth of each cell with respect to permanently surveyed benchmarks. The contents of each cell and the approximate location of each hazardous waste type within the cell must be recorded.
Bulk or noncontainerized liquid waste or waste containing free liquids must not be placed in the landfill. The exemption to this rule are that containers holding free liquids may only be placed in a landfill if they meet one of the following standards:
- all free-standing liquid has been:
- removed by decanting, or other methods
- mixed with sorbent or solidified so that free-standing liquid is no longer observed
- otherwise eliminated
- the container is very small, such as an ampule
- the container is designed to hold free liquids for use other than storage (for example, a battery or capacitor)
- the container is a lab pack.
In order to dispose of the sorbents used to treat free liquids in an hazardous waste landfill, the sorbent must be nonbiodegradable.
(NOTE: Approved sorbents include:
- inorganic minerals, other inorganic materials, and elemental carbon
- high molecular weight synthetic polymers, except for polymers derived from biological material or polymers specifically designed to be degradable
- mixtures of nonbiodegradable materials.)
Unless they are very small (such as ampules), containers must be at least 90 percent full and crushed, shredded, or similarly reduced in volume to the maximum practical extent.
The final cover of a hazardous waste landfill must be designed and constructed for the long term to:
- minimize migration of liquids through the closed landfill
- function with minimum maintenance
- promote drainage and minimize erosion or abrasion of the cover
- tolerate settling and subsidence so that the cover's integrity is maintained
- have a permeability less than or equal to the permeability of the bottom liner system or natural subsoil present.
The following documents are required as a part of closure:
- a certification of closure sent to the Regional Administrator by registered mail within 60 days of closure
- a survey plat submitted to the local zoning authorities (or the authority with jurisdiction over local land use) and the Regional Administrator no later than the submission of the certification of closure.
During postclosure the integrity and effectiveness of the final cover must be maintained, including making repairs to the cap (cover) as necessary to correct the effects of settling, subsidence, erosion, or other disruptive events.
During postclosure all leak detection systems and groundwater monitoring system are required to be maintained.
Postclosure care usually lasts 30 yr after closure.
Summary of State Requirements
This is an area in the management of hazardous waste where typically the states simply adopt the Federal requirements.
Laws and Statutes
The Clean Air Act