Groups demand EPA action on dispersants

Alan Bailey

Petroleum News

Environmental groups and some people from Alaska communities have sent a letter to the Environmental Protection Agency, giving the agency 60-day notice of a lawsuit if the agency does not issue new rules for the use of dispersants in response to an offshore oil spill, according to a report from the Associated Press. The notice refers to a proposed rulemaking that the EPA announced in the Federal Register in January 2015, the report says.

The new rule would revise criteria for listing dispersant products that may be approved for use in a response and would clarify the criteria for removing an item from the schedule of products in the National Contingency Plan. There would also be amended requirements for authorization, notification, monitoring and data reporting when using chemical agents during an oil spill response. There was a 60-day public comment period following the announcement of the proposed rule, but the EPA never published a final rule.

Dispersants work by breaking an oil slick into minute oil droplets that spread out through the water column. These droplets are consumed by naturally occurring microbes much more quickly than if the oil persists in the form of a slick. Thus, the use of a dispersant can greatly speed up the rate at which spilled oil breaks down into relatively harmless material, potentially reducing the environmental impact of the spill. However, there are concerns about both the toxic impact of dispersed oil on the marine environment, and the toxic impact of the dispersants themselves. Some Alaska coastal communities worry in particular about potential impacts on marine subsistence resources.

The use of dispersant during a spill response requires approval from the U.S. Fish and Wildlife Service and the National Marine Fisheries Service. The National Contingency Plan includes a schedule of dispersants that have been reviewed by the EPA. Listing of a dispersant in this schedule requires, among other things, the submission of technical data on the product. Data must include the results of toxicity tests and dispersant effectiveness testing. However, the approval of the use in a response of a specific dispersant in this list requires approval, based on the circumstances of that particular response.

- ALAN BAILEY