The following story was written and reported by Talli Nauman. All content © Native Sun News.

BROWNING, MONTANA -- The Environmental Protection Agency’s Criminal Investigation Division is reviewing oil company failure to report a pipeline spill into the Cut Bank River in the Blackfeet Nation of north-central Montana.

The incident occurred about a week before the July 1 break on ExxonMobil’s tar-sands crude-oil pipeline drew federal emergency response teams to a larger spill on a stretch of the Yellowstone River near the Apsáalooke (Crow) Nation territory in south-central Montana.

FX Drilling Inc., based in Oilmont, Montana, did not report the spill into the Cut Bank, so it was not until an anonymous caller alerted officials on July 12 that the tribal government advised the federal authorities, according to the Blackfeet Environmental Office (BEO).

As of July 21, the Blackfeet Tribe was still awaiting a response from FX Drilling Inc. as to why BEO and the tribe were not notified when the spill took place, the office informed Native Sun News.

The EPA requires a company to report a waterway oil spill within a 24-hour time-frame. The Cut Bank and the Yellowstone are tributaries of the Missouri River, which drains several South Dakota tribal territories.

The Blackfeet Tribe admonished the company to be more careful, saying, “FX Drilling, Inc. as well as any other oil and gas company working within the exterior boundaries of the Blackfeet Indian Reservation need to communicate to the Blackfeet Tribal Business Council, BEO, and other pertinent tribal departments as soon as possible when these types of events occur.”

The business council, headquartered in Browning, Montana, is the highest federally recognized tribal authority of the Blackfeet Nation.

“Immediate communication to the proper authorities would ensure that the appropriate containment, mitigation, and clean-up measures take place in a timely manner,” the environmental office stated.

A seven-member delegation of the Apsáalooke Nation toured the Yellowstone River cleanup project on July 21. Tribal administrators are entitled to involvement in all aspects of the 440-person EPA-led Unified Command clean-up process, including recommendations and sign-off, the EPA said. It said ExxonMobil Pipeline Co. is the party being held accountable for assessment and cleanup. However, at the agency’s request, the company has agreed to provide health and safety training to Apsáalooke Nation members so they can fully participate in the response.

Montana’s state government urged citizens to report effects of the rupture on ExxonMobil’s Silvertip Pipeline that dumped toxic sludge into the Yellowstone at Laurel, Montana, about 20 miles upstream of Billings.

ExxonMobil’s estimate of the amount released was about 1,000 barrels (42,000 gallons). The volume of the Cut Bank spill remains a mystery, according to the BEO. However, reports are that it was a very small fraction of the amount spilled into the Yellowstone.

The Cut Bank joins Two Medicine River to form the Marias River about 100 river miles upstream from the Missouri. The Marias is known as a prime boating and fishing waterway.

On July, 20, Montana Gov. Brian Schweitzer established an Oil Pipeline Safety Review Council to advise him on “the status of all existing oil pipelines running underneath Montana’s rivers and streambeds,” as stated in Executive Order No. 10-2011.

Cleanup crews have completed the initial stage of work on four of 25 identified spill sites on the Yellowstone, which were chosen due to large quantities of easily accessed debris and vegetation.

The crews also have completed assessment of more than 1,200 acres in and along the river corridor. However, effective cleanup methods are hard to find, the EPA said last week.

On July 20, crews tested a high water-pressure device for cleansing flood debris. “This method proved to be ineffective for removing oil and will not likely be used as a cleanup technique,” the EPA said in a written statement.

The agency said it is not considering burning flood debris piles at this time, but might in the future. “This is primarily due to technical and logistical constraints specific to the sites currently under review,” it said.

An S-61 heavy-lift helicopter was tested in preparation for transporting equipment, such as loaders, chippers and small dumpsters to the river’s islands to support upcoming efforts, the EPA reported.

Administrators expected to make decisions on ExxonMobil’s July 19 revised work plan early in the week of July 24.

Officials evacuated 140 people from Laurel on July 16, as a precaution against a possible explosion. The people were allowed to return on July 17. Water and air quality monitoring are underway.

Rescue efforts for oiled birds and other wildlife are ongoing. The river banks serve as nesting areas for migratory birds.

The polluted stretch of the Yellowstone River is home to the pallid sturgeon, an endangered fish species.

Oil has spread onto thousands of acres of wetlands outside the of river banks, “contaminating the primordial mix of microbes that spawns life itself,” the state government said.

(Talli Nauman is Health and Environmental Editor for Native Sun News. Contact her at talli.nauman@gmail.com)