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Federal Post-Closure Rule State Regulations: FAQs

Addition of Enforceable Documents and Flexibility for
Postclosure Requirements
(Postclosure Rule)

What does the term “postclosure” mean?

When a hazardous waste management unit stops receiving waste and the owner has determined it is at the end of its active life, it must be closed in accordance with federal and state closure requirements. Closure can occur as a “clean closure” or with “waste left in place.”

Clean closure means the owners remove all wastes from the unit and decontaminate or remove equipment, structures, and contaminated soil. These activities avert the risk of future chemical exposures to human health and the environment. Units can also undergo closure that leaves waste in place.

However, owners of these units must conduct postclosure activities such as inspecting, monitoring, and maintaining systems that contain the waste and protect the surrounding environment and community from hazardous waste releases.

What is the Postclosure Rule?

The Postclosure Rule is a Department of Toxic Substances Control (DTSC) regulation based on portions of the Federal Post-Closure Rule of 1998 (Federal Post-Closure Rule). In 2016 Senate Bill (SB) 1325, effective January 1, 2018, amended Section 25247 of the Health and Safety Code, providing DTSC with authority to impose postclosure requirements through the issuance of an enforcement order or an enforceable agreement. DTSC already had authority to require a hazardous waste postclosure facility permit (postclosure permit) at facilities with hazardous waste left in place that are subject to postclosure care requirements.

The Postclosure Rule incorporates selected text and concepts from the Federal Post-Closure Rule, found in 40 Code of Federal Regulations Parts 264, 265, and 270. The Postclosure Rule established sections 66264.121, 66265.121, and 66270.28 and revised sections 66264.90, 66264.110, 66265.90, 66265.110, 66270.1(c), and 66270.14(a) of California Code of Regulations, title 22, Division 4.5.

What is the purpose of the Postclosure rule?

Prior to the Postclosure Rule, DTSC’s only available option to enforce postclosure care activities required postclosure plans to be approved and enforced through either the issuance of a postclosure permit or the modification of an operating permit.

The Postclosure Rule gives DTSC the flexibility to use enforceable documents (typically a corrective action order or a remedial action order, issued pursuant to Health and Safety Code sections 25187 or 25355.5(a)(1)(B), respectively) at facilities with hazardous waste left in place that need or already have a postclosure permit. Enforceable documents require and ensure compliance with federal and State hazardous waste control requirements to mitigate environmental risks at facilities subject to the postclosure permit requirement. The ability to use enforceable documents allows DTSC to use the appropriate authority based on the circumstances of the facility. The Postclosure Rule provides DTSC options to requiring a postclosure permit while providing the same substantive postclosure care and corrective action requirements and ensure continued public participation.

When did the Postclosure Rule become effective?

California’s Federal Post-Closure Rule: Addition of Enforceable Documents and Flexibility for Postclosure Requirements (Postclosure Rule, as opposed to the Federal Post-Closure Rule) became effective on January 1, 2019.  See DTSC’s Postclosure Rule web page.

Who is affected by the Postclosure Rule?

The Postclosure Rule applies to facilities that intend to leave or already have left hazardous waste in place and so are required to conduct postclosure care. Typically, the Postclosure Rule pertains to closed hazardous waste landfills that contain waste and therefore are required to monitor the site and surrounding area for potential contaminant releases in accordance with California Code  of Regulations, title 22, Division 4.5, Chapters 14, 15, or 20.

The Postclosure Rule affects DTSC, as DTSC has the discretion to determine whether application of the Postclosure Rule may be appropriate for a postclosure facility.

What is the history of the Postclosure Rule?

In 1998, the United States Environmental Protection Agency (U.S. EPA) adopted the Federal Post-Closure Rule, which modified the federal Resource Conservation and Recovery Act (RCRA) regulations to allow the use of enforcement mechanisms such as enforcement orders and enforceable agreements. U.S. EPA already had the authority to use postclosure permits to impose requirements on nonpermitted (e.g., Interim Status) land disposal units requiring postclosure care. However, states are not required to adopt the Federal Post-Closure Rule. (63 Fed. Reg. 56710, 56729 (10/22/98).)

In 2003 the California Legislature adopted Assembly Bill 1247 (Stats. 2003, c. 286, §1), allowing DTSC to impose postclosure care requirements through the issuance of an enforcement order, enforceable agreement, or postclosure permit. This legislation also included a sunset provision terminating DTSC’s authority to enter into orders and agreements, effective January 1, 2009. (Former Health & Safety Code, §25247(f)(1).)

On January 1, 2009, the sunset provision went into effect, essentially prohibiting DTSC from using alternative enforcement mechanisms for postclosure permit requirements.

On May 12, 2011, DTSC adopted a portion of the 1998 Federal Post-Closure Rule that gives DTSC discretion and the ability to use corrective action requirements, rather than closure requirements, to address hazardous waste land-based disposal units, including regulated units with a release that is commingled or mixed with a groundwater release from another solid waste management unit. (Cal. Code of Regs., title 22, §§ 66264.90 & 66265.90 et seq.; see DTSC Water Quality Monitoring Requirements for Hazardous Waste Land Disposal Units, R-2004-11, adopted 4/12/11).) For a copy of the regulations, go to the following link: https://dtsc.ca.gov/wp-content/uploads/sites/31/2018/07/Final-Text-of-RegulationsWater-Quality-Monitoring.pdf.

In 2016, Governor Brown approved SB 1325 (Stats. 2016, c. 676, §1.5), which amended Section 25247 of the Health and Safety Code to restore DTSC’s authority to impose postclosure requirements through the issuance of an enforcement order or enforceable agreement at facilities with hazardous waste left in place that are also subject to a postclosure permit. In addition, SB 1325 required DTSC to adopt regulations to impose postclosure plan requirements through alternative enforcement mechanisms.

The Postclosure Rule regulations adopted pursuant to SB 1325 became effective January 1, 2019.

How is the Postclosure Rule different than the 1998 Federal Post-Closure Rule?

The 1998 Federal Post-Closure Rule applies only to interim status facilities and facilities that have not received a hazardous waste operating or postclosure permit. The Postclosure Rule, however, applies to facilities that have or have not received a hazardous waste permit.

By allowing the option for alternative mechanisms at both permitted and unpermitted facilities, the Postclosure Rule provides DTSC with the ability to use enforceable documents to authorize required hazardous waste postclosure care activities based on a particular facility’s conditions and the risks posed by that facility.

DTSC’s authority to adopt portions of the Federal Post-Closure Rule was limited by SB 1325. SB 1325 did not provide an option for DTSC to enforce the closure portion of the Federal Post-Closure Rule; however, flexibility currently exists based on existing closure regulations and U.S. EPA guidance that allows a facility to move to closure through corrective action if a release occurs or clean closure is not practicable.

What types of units and materials undergo postclosure care?

During closure, some hazardous waste management units are closed with hazardous wastes left in place. These units include landfills, land treatment units, surface impoundments, and other units that require postclosure care. In addition, the associated equipment, structures, and soils that cannot be fully decontaminated or clean-closed will also require postclosure care.

Postclosure care activities consist of maintaining the integrity of the waste containment units, monitoring and reporting unit activities, preventing or controlling contaminant releases, and ensuring that monitoring equipment is working properly.  Owners and operators of a facility are required to ensure appropriate monitoring and maintenance activities are conducted to protect human health and the environment.  The owners and operators are required to cover costs for postclosure care that includes long-term maintenance of the unit or facility, monitoring, record keeping, providing detailed written cost estimates and a financial mechanism to pay for postclosure care in case the facility is abandoned.

What is the purpose of an enforceable document?

Issuing an enforceable document such as an enforcement order, enforceable agreement, or postclosure permit allows DTSC to impose postclosure care requirements based on the circumstances of a facility.

The Postclosure Rule provides alternatives to the postclosure permit while providing the same substantive postclosure care and corrective action requirements as a postclosure permit, and with continued public participation.

What are the benefits of the Postclosure Rule?

Under the Postclosure Rule, DTSC is not limited to using postclosure permits as an authorization mechanism. The Postclosure Rule allows DTSC to choose an enforceable document such as an enforcement order, enforceable agreement or postclosure permit that best fits the particular needs at a facility that is applicable to federal and state requirements and provides continued protection of human health and the environment. DTSC may opt for an enforceable document over a permit in situations that include, but are not limited to, when a facility does not meet financial assurance requirements, its owners or operators are recalcitrant or out of compliance, or an approved alternative Cleanup Authority is available (Cleanup Authority; California Hazardous Substance Account Act, also known as the State Superfund Law; Chapter 6.8 of Division 20 of Health and Safety Code).

The substantive RCRA permitting requirements are not terminated but applied pursuant the enforcement of corrective action or remedial action authorities. (Health & Safety Code, §§25187 & 25355.5(a)(1)(B), respectively.)

The two most common difficulties that DTSC encounters when evaluating postclosure permit applications are:

  • First, some facilities cannot comply with the permitting requirements, particularly groundwater monitoring and financial assurance. If the facility is not able to meet the postclosure care requirements, DTSC cannot issue a postclosure permit. (Health & Safety Code, § 25200.)
  • Second, owners and operators often have little incentive to seek a postclosure permit for a facility that is not generating any revenue because it is not operating. This lack of incentive can cause the permitting process to be significantly prolonged.

What are the fees for an applicant under an enforceable document?

Facilities (open or closed) conducting postclosure activities under an enforceable document are required to enter into a cost reimbursement agreement to pay DTSC’s actual costs through the effective date of the order or agreement. Facilities are also required to pay all applicable annual facility fees. (Health & Safety Code, §25247(d)(3).)

DTSC anticipates minimal cost differences to hazardous waste facilities as a result of the Postclosure Rule. The costs of regulatory or administrative activities tied to enforcement documents may be lower than those associated with postclosure permits or permit modifications.

What type of landfill does the Postclosure Rule apply to?

The Postclosure Rule does not apply to nonhazardous waste landfills, such as municipal landfills. It applies to land-based hazardous waste management units (e.g., landfills, surface impoundments, land treatment, tank systems, and containment buildings) that are closed or are ceasing operations and are subject to hazardous waste postclosure care requirements because waste or residual waste will be left in place.

Does the Postclosure Rule include the closure requirement portions of the Federal Post-Closure Rule allowing (a) the use of corrective action processes for unit closure, and (b) the selection of one remedy for two separate regulatory authorities: regulated units (land-based) and solid waste management units (corrective action)?

No, the Postclosure Rule does not include the closure requirement portions of the Federal Post-Closure Rule. DTSC’s authority to adopt the Postclosure Rule is limited to the postclosure portion of the Federal Post-Closure Rule in accordance with SB 1325, which did not provide an option for enforcing a closure plan. However, DTSC already has some flexibility based on existing closure regulations and U.S. EPA guidance allowing a facility to move from closure to corrective action if a release occurs or clean closure is not practicable.

In addition, U.S. EPA allows risk-based clean closure and allows releases from hazardous waste management units to be addressed by corrective action or by recognized Cleanup Authorities. This allows DTSC to determine if a facility, even with closed units, could be subject to corrective action by determining if the unit could be contributing to a release.

DTSC also has State Superfund authority to address any type of release of hazardous substances under the Hazardous Substances Account Act (Health & Safety Code, §25300 et seq.), which gives DTSC the authority to issue an order or an agreement. Finally, the Postclosure Rule provides DTSC with the additional option of eliminating the requirement that a permit must be issued.

DTSC believes this approach provides an appropriate balance between the expectation that operating facilities in California will address the impacts of their operations with the realities of remediating releases from the past.

Does the Postclosure Rule allow enforceable documents to be issued by other state agencies, such as Water Boards?

Under the Federal Post-Closure Rule, an “enforceable agreement” is specifically defined as “an order, a plan, or other document issued by EPA or by an authorized State” that meets specified enforcement authorities set forth in federal regulations. (40 CFR §270.1(c)(7).) DTSC is the only California state agency authorized to implement a hazardous waste program in lieu of RCRA. Neither the Federal PostClosure Rule, SB 1325, nor the permitting consolidation program established by Health and Safety Code section 25204.6 (SB 1082) authorize the Water Boards (State Water Resources Control Board or the Regional Water Quality Control Boards) or any other agency to implement or enforce the provisions of RCRA.  However, DTSC does coordinate with the Water Boards to address corrective action requirements when the Water Boards are the lead for overseeing corrective action.

In cases where the Water Boards are the lead for corrective action, the facility can choose to request DTSC consider the use of the Postclosure Rule for a specific unit that has waste left in place. Such requests, however, would need to be coordinated with the Water Boards, and the decision whether to utilize the Postclosure Rule is at DTSC’s discretion.

If the complete Federal Post-Closure Rule had been adopted, wouldn’t that have given DTSC more efficient oversight at facilities with solid waste management units and regulated units?

DTSC determined that the flexible use of enforceable documents for postclosure care allowed by the Postclosure Rule, as well as the portion of the Federal PostClosure Rule adopted in 2010 that made changes to water quality monitoring requirements, are sufficient for efficient DTSC oversight.

The water quality monitoring requirements in California Code of Regulations, title 22, sections 66264.90 and 66265.90 et seq., which are also part of the Federal PostClosure Rule, provide DTSC with the authority to address regulated units and solid waste management units based on commingled contaminated groundwater plumes from different regulated units. Typically, different units with commingled plumes are located near each other. The combination of the regulations pertaining to water quality monitoring and the Postclosure Rule allows DTSC to oversee different types of units more efficiently based on administrative and geographic similarities.

Does the Postclosure Rule remove the required activities of the existing permitting process?

The Postclosure Rule is intended to address postclosure activities using enforceable documents but is not intended to change the permitting process itself, nor the requirements of Postclosure Care. The Postclosure Rule does provide flexibility as to which legal mechanism is used when imposing postclosure requirements and ending the 10-year cycle of permit renewals.

As with RCRA permits, does the Postclosure Rule employ enforcement mechanisms that are commensurate with the risk a facility poses?

To address environmental risks at facilities, DTSC already utilizes a variety of legal authorities, including permits, enforceable orders, and other enforceable documents.  Prior to adoption of the Postclosure Rule, DTSC was required to issue a postclosure permit even where the environmental risks associated with the facility were addressed through other authorities.

Does the Postclosure Rule allow the use of existing documents such as waste discharge requirements and land use controls to serve as an enforceable document?

Documents such as waste discharge requirements and land use controls are not appropriate to serve as an enforceable document instead of a postclosure permit because these documents do not include the prescriptive and authoritative requirements of postclosure care. Furthermore, these documents do not meet the regulatory definition of an enforceable document. The requirement to conduct postclosure care does not lapse until the facility removes all hazardous waste contamination caused by the release from a unit subject to postclosure care. Any expiration of a permit or state failure to issue a permit does not change this requirement. (Also, please see U.S. EPA OLEM Guidelines for Evaluating the PostClosure Care Period for Hazardous Waste Disposal Facilities under Subtitle C of RCRA (12/15/16): https://www.epa.gov/sites/production/files/2017-01/documents/pcc_guidance_508_withdateandletterhead.pdf.)

Many facilities and sites in California are already subject to other DTSC enforceable agreements or orders issued under the authority of the California Hazardous Waste Control Law (Chapter 6.5 of Division 20 of Health and Safety Code) and the California Hazardous Substance Account Act, also known as the State Superfund Law (Chapter 6.8 of Division 20 of Health and Safety Code). The Postclosure Rule allows those agreements or orders to include postclosure permit requirements, providing an alternative to issuing the permits themselves.

How does an owner/operator of a hazardous waste facility apply for the Postclosure Rule?

When DTSC determines an enforceable document may be appropriate in lieu of a postclosure permit, it will work with a hazardous waste facility to explore the Postclosure Rule option. However, use of the option is at DTSC’s discretion, even if a facility is potentially eligible.

DTSC’s staff and legal counsel will confer on the type of enforcement document to issue and weigh the benefits and disadvantages relative to the importance of assuring proper long-term postclosure care in accordance with regulations.

Does the Postclosure Rule enforcement document involve public participation?

When issuing enforceable documents instead of postclosure permits, DTSC will
ensure there is opportunity for public involvement which, at a minimum, includes
public notice and opportunity for public comment:

  • When DTSC becomes involved in remediation of a facility;
  • When a preferred remedy is proposed; and
  • When a decision is proposed that remedial action is complete.

As postclosure care activities progress, DTSC will provide, at a minimum, an
opportunity for public involvement during five-year reviews and when it is determined
that changes to the remedy are needed.

How will the Postclosure Rule address the lack of financial assurance by a facility?

DTSC can elect to use enforceable documents instead of a permit when facilities cannot meet postclosure permit financial assurance requirements. When this occurs, the enforceable document needs to account for that facility’s inability to provide financial assurance and lay out a plan for meeting the financial needs for postclosure care of the closed units in perpetuity, as appropriate. This will include provisions for cost recovery from past responsible parties, other  income streams, and other sources.

Does the Postclosure Rule have an interval for renewal or review, like the postclosure permit renewal process which occurs every 10 years?

After a facility is authorized under an enforcement document a remedy will need to be chosen, and five-year reviews will take place after the completion of the remedial action. Such reviews are repeated every succeeding five years as long as future uses remain restricted.