By William C. Schillaci
The federal self-implementing cleanup requirements for polychlorinated biphenyl (PCB) remediation waste are, like most self-implementing regulations, a mixed blessing.
EPA's regulations at 40 CFR 761.61(a) allow those responsible for PCB remediation waste to undertake cleanups without prior federal approval. Certainly, there is an advantage in not being told by a regulatory office how to conduct a cleanup. Conversely, responsibility to ensure that the correct cleanup targets are selected and met rests solely with the individuals in charge, who may need to explain and justify their cleanup decisions. A new EPA document, PCB Site Revitalization Guidance Under the Toxic Substances Control Act, provides cleanup managers with direction on making the right choices.
The guidance endeavors to give PCB cleanup decisions concrete form by providing "typical" and "worst case" PCB cleanup situations and discussing how these may be best addressed to comply with the regulations. By definition, PCB remediation waste takes four forms:
- Bulk PCB remediation waste
- Porous surfaces
- Nonporous surfaces
- Liquid PCBs
The guidance offers direction on characterizing, containing, and disposing of this waste.
The guidance was developed in part to help expedite the sale or transfer of properties contaminated with PCBs. Since the Toxic Substances Control Act (TSCA) does not allow the distribution in commerce of PCBs, the statute would also appear to prohibit sale or transfer of PCB-contaminated property. But EPA has decided that "distribution in commerce" does not apply to real properties contaminated with PCBs, for which ownership is transferred. The Agency has taken the position that blocking the sale of such properties would probably also hinder their cleanup. After the property transfer, the new owner becomes responsible for controlling and mitigating any continuing and/or future releases of PCBs.
Determining Cleanup Levels
For properties with soil contaminated with PCBs, the regulations indicate that the cleanup be based on three determinations:
- How the property will be used,
- Which type of waste material is contaminated, and
- Which cleanup level is appropriate.
More specifically, cleanup levels for an area contaminated with PCBs depend on the degree to which people will be exposed to residual contamination. Exposure is measured by the amount of time people will spend in the area, and the type of PCB contamination that will remain in place after remediation. The length of occupancy (how long a person is expected to be exposed to an area of contamination) generally depends on the intended use of the area. Areas in continuous or semicontinuous use, such as residences or schools, are generally classified as high-occupancy areas. Under the self-implementing provisions, areas that are used to a limited extent, such as electrical substations, are considered low-occupancy areas.
All PCB concentrations are based on total PCBs, rather than individual PCB Aroclors (commercial mixtures of PCB compounds). Reuse scenarios for a facility or property may result in a cleanup that utilizes a combination of standards (e.g., high-occupancy and/or low-occupancy area), depending on whether certain conditions are met (e.g., duration of access is limited; entry is secured, for example, by a key or combination lock). Note: In these cases, it is advisable for the individual in charge of the cleanup to consult with EPA's regional PCB coordinator to ensure that the level of protection will withstand regulatory scrutiny. Some states also have PCB regulations, so a call to your state solid waste office is essential.
In addition, PCB provisions at 40 CFR 761.61(c) establish a procedure for individuals to conduct a PCB cleanup or disposal that differs from the prescribed self-implementing requirements. Such a cleanup would have to result in a commensurate level of protection for human health and the environment. This type of cleanup would not be self-implementing, and an individual would need to apply to the EPA regional administrator for approval to conduct the work.
Also, the self-implementing procedures may not be used to clean up surface or groundwaters, sediments in marine and fresh water ecosystems, sewers or sewage treatment systems, any private or public drinking water sources or distribution systems, grazing lands, and vegetable gardens.
Following are explanations of the three steps for determining the applicable PCB cleanup levels for self-implementing cleanups.
Step 1: How Will the Property Be Used?
New uses of a property are classified as high or low occupancy.
A high-occupancy area is defined as any area where PCB remediation waste has been disposed of on-site (including but not limited to any building, any floor/wall of the building, any enclosed space within the building), and where annual occupancy for any individual not wearing respiratory protection is 840 hours or more for nonporous surfaces and 335 hours or more for bulk PCB remediation waste. Examples: residence, school, and cafeteria in an industrial facility, workstation at an assembly line.
A low-occupancy area is generally defined as any area where PCB remediation waste has been disposed of on-site (including but not limited to any building, any floor/wall of the building, any enclosed space within the building), and where annual occupancy for any individual not wearing respiratory protection is less than 840 hours for nonporous surfaces and less than 335 hours for bulk PCB remediation waste. Examples: electrical substation, unoccupied areas outside buildings, non-office space in a warehouse.
Step 2: Which Type of Waste Material Is Contaminated?
The self-implementing regulations cover the four types of PCB remediation waste. PCB remediation waste is sampled and managed at its "as-found" PCB concentrations. Samples should not be based on post-excavation or demolition composite samples collected from waste piles and roll-off containers.
Bulk PCB remediation waste includes existing piles of soil, in-situ soil, sediments, dredged materials, muds, PCB sewage sludge, and industrial sludge.
Porous surfaces include noncoated or coated structural surfaces such as floors, walls, and ceilings made of concrete, brick, wood, plaster, and plasterboard that have been subsequently contaminated by spills from PCB liquids. Porous surfaces also include paints or coatings that have been applied to a nonporous surface such as metal. Determination that a PCB porous surface is clean is made by taking a core sample; wipes used to take surface samples are not appropriate. An appendix in the guidance includes one procedure for taking core samples from concrete.
Nonporous surfaces include smooth unpainted solid surfaces that limit penetration of liquid containing PCBs beyond the immediate surface. Nonporous surfaces include smooth uncorroded metal, natural gas pipe with a thin porous coating originally applied to inhibit corrosion, smooth glass, smooth glazed ceramics, impermeable polished building stone such as marble or granite, and high-density plastics.
Liquid PCBs are homogeneous flowable material containing PCBs and no more than 0.5 percent by weight nondissolved material.
Step 3: Which Cleanup Level Is Appropriate?
Upon completion, sampling must be employed for all cleanups to verify that the required level of cleanup has been achieved.
High-occupancy areas. The following cleanup levels apply. When a cleanup activity includes use of a cap, the owner of the site must maintain the cap in perpetuity and an institutional control, such as a deed restriction, must be implemented.
Bulk remediation and porous surfaces:
- Less than or equal to 1 part per million (< 1 ppm) PCBs in the soils, other residual waste, or porous surfaces without further conditions.
- Greater than (>) 1 ppm but < 10 ppm if the area is covered with an appropriate cap.
- Porous surfaces contaminated by an old spill of liquid PCBs where the concentration of PCBs in the spill was > 50 ppm and where the surface concentration of PCBs on the porous surface is currently greater than 10 micrograms per 100 square centimeters (> 10 µg/100 cm2) may continue in their original use or location provided the source of contamination has been removed and other conditions are met (see 40 CFR 761.30(p)). Post-verification sampling is not required. Porous surfaces contaminated by an old spill of liquid PCBs where the concentration of PCBs in the spill was > 50 ppm and where the surface concentration of PCBs on the porous surface is currently < 10 µg/100 cm2 are authorized for use under 40 CFR 761.30(p) without further conditions as long as the level remains at < 10 µg/100 cm2.
- < 10 µg/100 cm2 without further conditions. One of the decontamination procedures at 40 CFR 761.61(a)(4)(ii) must be used to remove or separate PCBs from nonporous surfaces or another appropriate procedure as specified at 40 CFR 761.61.(a)(5)(ii).
Low-occupancy areas. The following cleanup levels apply. When a cleanup activity includes use of a cap or a fence, an institutional control such as a deed restriction must be implemented and remain in perpetuity.
Bulk remediation and porous surfaces:
- < 25 ppm in the soils, other residual waste, or porous surfaces and an institutional control.
- > 25 ppm to < 50 ppm in the soils, other residual waste or porous surfaces provided the site is secured by a fence and posted with a sign that includes a PCB mark and an institutional control is implemented.
- >25 ppm to < 100 ppm provided the site is covered with an appropriate cap and an institutional control is implemented.
- Porous surfaces contaminated by an old spill of liquid PCBs where the concentration of PCBs in the spill was > 50 ppm and where the surface concentration of PCBs on the porous surface is currently > 10 µg/100 cm2 may continue in their original use or location provided the source of contamination has been removed and other conditions are met (see 40 CFR 761.30(p)). Post- verification sampling is not required. Porous surfaces contaminated by old spills of liquid PCBs where the concentration of PCBs in the liquid was > 50 ppm and where the surface concentration of PCBs on the porous surface is currently < 10 µg/100 cm2 are authorized for use under 761.30(p) without further conditions as long as the level remains at < 10 µg/100 cm2.
- < 100 µg/100 cm2 and implementation of an institutional control. One of the decontamination procedures at 40 CFR 761.79(b) must be used to remove or separate PCBs from nonporous surfaces.
Cleanup Levels for Liquid PCBs. Liquid PCB wastes not in compliance with the decontamination levels below must be disposed of in an approved incinerator or by an alternative disposal technology in accordance with 40 CFR 761.60(e).
Water containing PCBs:
- < 200 µg per liter (L) (approximately < 200 parts per billion [ppb] PCBs) for noncontact use in a closed system where there are no releases.
- < 3 µg /L (approximately 3 ppb) or a PCB discharge limit included in a permit issued under Sections 307(b) or 402 of the Clean Water Act for water discharged to a treatment works or to navigable waters.
- < 0.5 µg /L (approximately < 0.5 ppb PCBs) for unrestricted use.
Organic liquids and nonaqueous inorganic liquids containing PCBs:
- < 2 milligrams per kilogram (< 2 ppm) PCBs.
Sampling and Deed Restrictions
Under the self-implementing regulations, post-cleanup sampling is required in accordance with the applicable cleanup verification requirements. EPA advises that responsible individuals contact their regional PCB coordinators for guidance regarding a risk-based approval to use appropriate sampling procedures not listed in the regulations.
Deed restriction requirements listed at 40 CFR 761.61(a)(8) must be implemented for any site where PCBs remain at concentrations above the specified high-occupancy "walk away" level of < 1 ppm for bulk remediation waste and porous surface and < 10 µg/100 cm2 for nonporous surfaces.
Other items of importance addressed in the guidance include proper disposal of PCB remediation waste, cap requirements, recordkeeping requirements, storage of PCB waste, notification and manifesting requirements, marking requirements, PCB use authorizations, and spill cleanup requirements for recent spills.
The guidance should prove particularly useful for managers who can match their contamination conditions to situations described in the real-world examples provided throughout the document.
EPA's PCB Site Revitalization Guidance Under the Toxic Substances Control Act is available at http://www.blr.com/keyword. Type in em668pcb when prompted.
[Source: Environmental Manager's Compliance Advisor. Subscribe today!]