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EPA Update on Yellowstone River Oil Spill (Silvertip Pipeline), July 28, 2011

Release Date: 07/28/2011
Contact Information: Matthew Allen, (720) 237-7414; Libby Faulk, (406) 351-9014

EPA Update on Yellowstone River Oil Spill (Silvertip Pipeline), July 28, 2011
Matthew Allen, (720) 237-7414; Libby Faulk, (406) 351-9014

(Billings, Mont --, July 28, 2011) EPA continues to oversee the response to the ExxonMobil Silvertip Pipeline Spill on the Yellowstone River. At this point, there are nearly 900 personnel engaged in cleanup and shoreline assessment efforts. Unified Command has conducted helicopter lift operations to get equipment into areas that were previously inaccessible to cleanup crews and to remove contaminated debris. This has accelerated cleanup efforts and will enable contaminated debris piles to be removed more effectively. 
EPA is working with a team of local, regional, and national experts in an Agricultural Impact Subcommittee to develop a fact sheet for agricultural questions that will be made available to the public as soon as it is completed. This fact sheet will provide guidance to landowners on remediation techniques and will serve as a framework to address their concerns.
Sampling data results will be made available as quickly as validated results permit. A decision was made by Unified Command early on to ensure that all the response data associated with this incident be consistent with Montana DEQ methodology and standards. As such, we are using only certified labs in Montana and those businesses have been working diligently to process samples and data packages. When data becomes available it will immediately be posted to the maps section of the EPA website.
“Even though we’re all awaiting final testing results from the samples, this has not impeded our decision making for the cleanup or the speed of our response efforts,” said Steve Merritt, EPA On-Scene Coordinator. “Everyone is working diligently to get this data out to the public as soon as possible. Nevertheless, the preliminary results continue to support the conclusions drawn already about surface water, drinking water, and air throughout the area.”
Of greater significance, SCAT teams have surveyed most of Divisions A and B, and will continue working through Division C in the next several days. The SCAT process includes 3 phases: survey and develop cleanup instructions, clean the assessed area, and reassess the area to ensure that the instructions have been followed completely. The following is data related to the survey phase of Divisions A and B:
Division A includes the first 10 river miles downstream of the pipeline break. 561 acres, roughly 79% of the area in this first section, has been surveyed by the SCAT teams. Of those areas surveyed, approximately 39.8% of the shorelines had no oil observed, 7.9% had very light oil impacts, 15.8% had light oil impacts, 33.8% had moderate oil impacts, and 2.7% had heavy oil impacts. 
Division B includes the next 18 river miles beyond Division A. 1367 acres, roughly 78% of the area, has been surveyed by SCAT teams. Of those areas surveyed, approximately 39.2% of the shorelines had no oil observed, 22.4% had very light oil impacts, 32.4% had light oil impacts, 5.8% had moderate oil impacts, and 0.1% had heavy oil impacts. 
These figures reinforce the previous aerial and non-SCAT observations that impacts diminish as the distance from the pipeline break location and that the oil impacts are predominantly associated with the south bank of the river and on islands that were submerged during the flooding within Divisions A and B.

BACKGROUND: At approximately 11:00 PM on Friday, July 1 a break occurred in a 12-inch pipeline owned by ExxonMobil that resulted in a spill of crude oil into the Yellowstone River approximately 20 miles upstream of Billings, Montana. EPA's primary concern is protecting people's health and the environment. EPA will remain on-site to ensure cleanup and restoration efforts do just that. EPA continues to hold ExxonMobil, the responsible party, accountable for assessment and cleanup.

PLEASE NOTE: The next Media Availability Call will be held on Friday, July 29th at 3:30 p.m. For dial-in information please contact the individuals listed on this press release for more information.
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