EPA's Clean Water Act Hazardous Substance Worst Case Discharge Planning Regulations

The Environmental Protection Agency’s (“EPA”) proposed “Clean Water Act (“CWA”) Hazardous Substance (“HS”) Worst Case Discharge (A worst case discharge is the largest foreseeable discharge in adverse weather conditions, including those from climate change.) (“WCD”) Planning Regulations” are under final review and are set to be published as a final rule no later than September 2024. As no final drafts have been published, this article will focus on what will be coming down the pipeline and provide adequate time for the regulated community to start preparing.

Background (https://www.epa.gov/hazardous-substance-spills-planning-regulations/proposed-rulemaking-clean-water-act-hazardous)

On March 21, 2019, the Natural Resources Defense Council, Clean Water Action, and the Environmental Justice Health Alliance for Chemical Policy Reform filed suit in the United States District Court for the Southern District of New York, alleging violations of the CWA section 311(j)(5)(A)(i) and the Administrative Procedures Act (“APA”). The plaintiffs and the EPA entered into a consent decree on March 12, 2020, that resolved the suit's claims. (Read the decree here: https://www.regulations.gov/docket/EPA-HQ-OGC-2019-0667.

On March 10, 2022, EPA Administrator Michael Regan signed a proposed rule to require certain facilities to develop facility response plans (“FRP”) for a WCD CWA HS, as well as for any threat of such a discharge. A WCD is the largest foreseeable discharge in adverse weather conditions, including those from climate change. (Read the rule here: https://www.ecfr.gov/current/title-40/chapter-I/subchapter-D/part-117/subpart-A/section-117.3).

The  FRP requirements would apply to facilities that could reasonably be expected to cause substantial harm to the environment based on their locations. These include industrial facilities with a maximum onsite capacity of a CWA HS that meets or exceeds threshold quantities, located within a 0.5-mile radius of navigable water or conveyance to navigable water, and meets one or more substantial harm criteria.

The proposed action considers the increased risks of WCD from climate change and the impacts on communities with environmental justice concerns.

The public comment period on the proposed rule was closed on July 26, 2022. Comments can be viewed at www.regulations.gov (Docket No.: EPA-HQ-OLEM-2021-0585).

The Federal Register Notice for the CWA HS WCD Planning Regulations Proposed Rule can be viewed here: https://www.federalregister.gov/documents/2022/03/28/2022-05505/clean-water-act-hazardous-substance-worst-case-discharge-planning-regulations 

               Image provided by U.S. EPA Office of Emergency Management September 2023 Update.

Key proposed provisions and applicability determination:

(Information taken from US EPA Office of Emergency Management’s September 2023 Update.)

Proposed CWA HS Reportable Quantity (RQ) Multiplier (subject to change once the rule is published):

• EPA designated 296 CWA HS under 40 CFR 116.
• The RQs were established from categories of quantities EPA deemed harmful based on acute aquatic toxicity, set in 40 CFR 117.3.
• A 10,000x multiplier of the RQ was set as the threshold amount.
• The provisions propose using onsite storage capacity rather than quantity on-site.

Proposed toxicity thresholds:

• Adult fathead minnow tests used to create the original RQ classification; they are available for all 296 CWA HS.
• The provisions propose 10% of the Lethal Concentration 50 (LC50) to extrapolate to lower concentrations than the lethal dose that is more relevant to discharges of hazardous substances to the environment.
• If a facility exceeds the maximum capacity onsite for a CWA HS, the owner/operator must determine proximity to navigable water. The onus for these calculations will be on the owner/operator.
• It is also being proposed that any facility owner or operator whose nearest discharge opportunity is within 0.5 miles of navigable water or conveyance must complete a planning distance calculation.
• Consistent with the approach in 40 CFR 112 for oil (precedent).
  • Location of fish and wildlife and sensitive environments (FWSE) receptors.
• Whether a WCD of CWA HS would result in offsite receptors being exposed to a concentration meeting or exceeding the concentration on the list provided by the EPA.

Similar to an FRP under the EPA’s Oil Pollution Act of 1990 (OPA90) requirements under 40 CFR Part 112.20, under the proposed rule, this FRP would require the following plan to include these components.

•  Specific substantial harm criteria worksheet, including the following new nuances from the oil approach:
  • Public receptor: parks, recreational areas, docks, or other public spaces inhabited, occupied, or used by the public at any time where members of the public could be injured due to a WCD into navigable waters.
    • Same planning distance parameters recommended for FWSE, but toxicity thresholds are set at 10% of the RQ concentration value for mammalian oral toxicity for each RQ category.
    • The operator has had a discharge of a CWA HS above the RQ that reached water within the last five years.
• Facility information
• Owner/Operator information
• Hazard evaluation
• Reportable discharge history
• Contracts
• Notification lists
• Discharge information
• Personnel roles and responsibilities
• Response equipment information
• Evacuation plans
• Discharge detection systems
• Response actions
• Disposal plans
• Containment measures
• Training procedures
• Drills and exercises
• Self-inspection
• Consistent with National Contingency Plan (NCP) and Area Contingency Plans (ACP)

Unlike the EPA’s oil FRP, the new rule proposes coordination with public water systems. Facility owners/operators would need to work with water facilities to determine whether a WCD would result in a concentration at a downstream public water intake that could result in any of the following:

• Violating any National Primary Drinking Water Standard or State Drinking Water Regulation;
• Compromising the ability of the drinking water treatment facility to produce water that complies with any National Primary Drinking Water Standard or State Drinking Water Regulation;
• Posing a risk of adverse health impacts in people exposed;
• Contaminating public water system infrastructure; or
• Impairing the water's taste, odor, or other aesthetic characteristic.

The list above is not exhaustive, nor should it be considered final. However, it provides summaries of what the EPA has shared publicly. Operators with an EPA oil FRP should be able to augment their plan to address these new planning requirements, as much of what is being proposed is already captured in an oil FRP. For those previously exempt under the EPA’s oil FRP rule, this will be a new plan development. 

For now, for operators who have CWA HS onsite, this rulemaking should be on your radar, and you should be prepared to act quickly once the final rule is published. How long will you be given to comply? This, too, has not yet been published.

If you have questions about how this development may impact your business operations, don’t hesitate to contact John K. Carroll III, Associate Managing Director, Witt O’Brien’s/Ambipar, at jcarroll@wittobriens.com. 

About the Author

John K. Carroll III