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Laura Alvey
Environmental Science Specialist
Remediation Division
(406) 841-5062 or call toll free (800)-246-8198 during business hours

Lisa Peterson
Public Affairs Coordinator
Director's Office
(406) 444-2929

Yellowstone River Oil Spill
Yellowstone River Oil Spill Assistance & Information

Silvertip Oil Spill

The Montana Department of Environmental Quality (DEQ) continues to monitor the site of the Silvertip Pipeline spill into the Yellowstone River this past summer. On Friday night, July 1, 2011, an estimated 1,500 barrels, or 63,000 gallons of crude spilled into the fast-moving, flood-stage river when ExxonMobil’s Silvertip Pipeline broke near Laurel. The 12-inch pipeline was buried about four feet under the river bed. What caused it to sever is still under investigation.

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At the time, the high water was over-bank, so oil reached shoreline properties, riparian areas, fields and pastures. People were evacuated from their homes as the worst of the crude chemicals vaporized into dangerous fumes. Some people sought medical care. At least 150 property owners suffered setback. Lives and livelihoods were disrupted.

The DEQ was appointed the official response agency for the State. DEQ Deputy Director Tom Livers left Helena over the weekend and rushed to the Incident Command Center in Billings to valiantly serve as State Incident Commander for the response, a position requiring 24/7 focus.

On July 5, Montana Governor Brian Schweitzer issued an Executive Order declaring an emergency in Yellowstone, Treasure, Rosebud, Custer, Prairie, Dawson and Richland Counties along the Yellowstone River due to the oil spill. Governor Schweitzer made it clear he’ll hold ExxonMobil accountable, and the cleanup will be done to Montana’s strict standards.

“The cleanup is done when the State of Montana says it’s done,” said Governor Schweitzer as he toured the site early on, and then again to a packed public meeting in Billings, one week after the spill. In addition, the US EPA issued an Administrative Order for ExxonMobil for clean up.

Governor’s Billings Office
The week following the spill, Governor Brian Schweitzer set up a special office in Billings for public information. Citizens were invited to visit the office, voice concerns and ask questions. Within the first two weeks, the office had received more than 200 calls, visits and emails. The State also set up a website

Emergency Response and Cleanup
The pollution was worse near the source of the spill at Laurel, 20 miles upstream from Billings. However, scoping, or SCAT teams, for Shoreline Cleanup Assessment Technique, found oil as far as 72 miles downstream from the spill site. Officials estimate that only 1 % of the oil released can be recovered because the swift current swept much of it away.

In the first weeks, crews mopped up free-floating oil with booms and absorbent pads. That left oil-saturated soil and sediment, and hard-to-reach, crude-laced debris piles to treat with a dust fixative, or by other means. If traversing or getting equipment to an area would cause more harm to the eco-system than do good, we won’t go there. The oil will be monitored as it naturally attenuates, or breaks down.

DEQ works with EPA to check, monitor and dog the scoping, sampling and cleanup done by ExxonMobil and its contractors. DEQ staff joined SCAT teams. The State did its own testing of crude, and started its own sampling program for landowners.

One month after the spill, more than 1,000 were being employed on the effort. Thirty percent were Montanans. It was at the insistence of the State that more Montanans were hired. Eventually, the emergency response and cleanup will yield to long-term remediation and restoration of the river system. DEQ will be the lead in that oversight.

Montana Scientists Helping Montana Landowners
By the first week in August, state sampling results were ready. Analysis of crude oil taken from a section of pipeline shows the petroleum components are consistent with what’s found in crude oil. It did not contain a lot of heavy metals or toxic additives that persist for long periods in the environment.

In mid-July, the Governor launched a sampling program “Montana Scientists Helping Montana Landowners.” Property owners, or upon their request, DEQ scientists and contractors sampled drinking water, irrigation water, surface water, and oiled soil. The program served 40 properties. At the time, at least 14 drinking water wells and 6 irrigation wells had been tested. In addition, at least seven samples were collected from surface water bodies such as oxbows, sloughs or puddles. Four of the wells had trace concentrations of various chemical constituents, though none raised undue concern.

“We’re happy that none of the petroleum-related chemicals we tested for exceed drinking water standards,” DEQ Director Opper said. “As an extra precaution, we do intend to resample the four wells.”

Out of 87 soil samples taken from 23 properties, at the time, nine of those properties showed no risk from crude oil. Low concentrations of petroleum constituents were found at seven properties, and seven properties had petroleum concentrations that required cleanup.

“We encouraged people to sample the worst parts of their property, so we’re not surprised to find evidence of crude oil in their soil,” Governor Schweitzer said. “But it appears that what we did find was the heavier components of the oil. The lighter, smellier, more toxic elements of the oil have largely evaporated or weathered away, which may be comforting news for the affected landowners.”

Pipeline Safety Council
By Executive Order on July 20, 2011, Governor Schweitzer established the Montana Oil Pipeline Safety Review Council to investigate pipeline river crossings in Montana and recommend steps to prevent pipeline breaks and spills. The Council has held two meetings and will meet again on Wednesday, February 8, 2012, 9 a.m. – noon, room 137, Montana State Capitol, Helena. DEQ Director Richard Opper chairs the Council. Department of Natural Resources and Conservation Director Mary Sexton and Department of Transportation Director Tim Reardon serve. DEQ will make reasonable accommodations for people with disabilities who wish to participate in the meeting. For more information about the Pipeline Council, please visit the Montana Oil Pipeline Safety Review Council web page. 

“We need to know every pipeline, its diameter, shut-off valves, pressure levels, what product it’s carrying, and inventory all regulations,” said Governor Schweitzer. “We need regulatory agencies with teeth.” He said accidents happen, but we must work to prevent them.

The Governor stressed that Montana will continue to drill for oil and gas. “We don’t want to slow down energy production but we need to do it right,” said Governor Schweitzer.

The Yellowstone River spill drew worldwide attention, grabbing national and international headlines for weeks. The incident opened the nation’s eyes to pipeline safety and triggered a collective promise of lasting resolve.