United States Environmental Protection Agency Office of Land and Emergency Management July 2021 www.epa.gov/emergency-response Dispersant Monitoring Provisions Under Subpart J of the National Contingency Plan - Final Rule The U.S. Environmental Protection Agency (EPA) is finalizing monitoring requirements under Subpart J of the National Contingency Plan (NCP) for dispersant use in response to major oil discharges and certain other atypical dispersant use situations in the navigable waters of the United States and adjoining shorelines. These provisions will equip the response community with data and information to authorize and use dispersants in a judicious and effective manner. In April 2010, the Deepwater Horizon underwater oil well blowout discharged significant quantities of oil into the Gulf of Mexico. The blowout discharged oil from one mile below the sea surface. Approximately one million gallons of dispersants were deployed on surface slicks over a three-month period on thousands of square miles of the Gulf of Mexico. Additionally, approximately three quarters of a million gallons of dispersants were, for the first time, injected directly into the oil gushing from the well riser. The Deepwater Horizon incident raised questions about the challenges of making dispersant use decisions in response operations for certain atypical dispersant use situations. Summary of Proposed Rule Amendments On January 22, 2015, EPA published a proposed rule to amend Subpart J of the NCP. The proposed amendments are a major component of EPA's effort to inform the use of dispersants and other chemical or biological agents when responding to oil discharges. The proposed amendments were intended to ensure that On-Scene Coordinators (OSCs), Regional Response Teams (RRTs), and Area Committees (AC) have relevant information to support response decision-making regarding dispersant use. They also incorporate lessons learned from the Deepwater Horizon response. Key areas addressed in the 2015 proposed Subpart J amendments included: • Authorization of use requirements for chemical agents; • Toxicity and efficacy testing protocols, information requirements, and procedures for listing products on the Subpart J Product Schedule; and • New monitoring requirements for subsurface, major oil discharges, and prolonged surface application of dispersants. The Agency received public comment submissions from industry, academia, state and local governments, environmental groups, and individuals on the 2015 proposal. The Dispersant Monitoring Provisions Under Subpart J of the National Contingency Plan final action establishes new dispersant monitoring requirements. The remaining provisions addressed in the 2015 proposed rule (i.e., authorization of use, testing protocols, and listing) are currently under consideration. Office of Emergency Management History ------- Subpart J Monitoring Requirements - Final Rule July 2021 Final Dispersant Use Monitoring Requirements Environmental field monitoring data can support decision-making when dispersants are used in response to an oil discharge. The data provide site-specific information on the overall effectiveness, including the transport and environmental effects, of the dispersants and the dispersed oil. Dispersant-use monitoring provides information on the transport of dispersed oil in the water column to inform sampling as well as potential environmental effects. The monitoring provisions are to ensure that the OSC and other agencies with responsibility for authorizing dispersant use have relevant information under certain atypical use situations for decision-making. These monitoring requirements apply to the responsible party of an oil discharge. The amendments establish dispersant monitoring requirements when responding to oil discharges as follows: • Subsurface - Any subsurface use of dispersants, • Prolonged Surface - Any surface use of dispersant for more than 96 hours after initial application, and • Major Oil Discharges - Any surface use of dispersant in response to oil discharges of more than 100,000 U.S. gallons occurring within a 24-hour period. The monitoring elements in the final rule cover several key areas including: • Source Characterization and Information on Dispersant Application - Oil discharge flow rate or volume as applicable, dispersant choice, dispersant-to-oil ratio, application rates, and total amount of dispersant needed. • Water Column Sampling - Background, baseline, and dispersed oil plume water column in- situ sampling for oil droplet size distribution, fluorometry and fluorescence, total petroleum hydrocarbons, dissolved oxygen (subsurface only), methane (subsurface only), heavy metals, turbidity, water temperature, pH, and conductivity. • Oil Distribution Analysis - Characterization of dispersant effectiveness and oil distribution. • Ecological Characterization - Characterization of potential ecological receptors and habitats, and their associated exposure pathways. • Immediate and Daily Reporting - Reporting to the OSC and RRT immediately for specified application deviations, and daily for water sampling and data analyses. For More Information Read the Proposed Subpart J Rule Amendment: http://www.epa.gov/emereencv-response/national-contingencv-plan-subpart-i Visit the EPA Emergency Response Website: http://www.epa.gov/emergencv-response Call the National Contingency Plan Product Schedule Information Line (202) 260-2342 (phone) To Report an Oil or Chemical Spill Call the National Response Center: (800) 424-8802 or (202) 267-2675 TDD (202) 267-4477 Office of Emergency Management ------- |