United Group Insurance

PIPELINE LEAK IN MISSOURI RIVER FLOOD PLAIN IN MONONA COUNTY

News

August 14th, 2011 by Ric Hanson

ONAWA, IA – A pipeline carrying natural gasoline developed a leak over the weekend,
with the potential to lose about 140,000 gallons of gasoline in the Missouri River
floodplain southwest of Onawa.

Enterprise Products of Houston, Tex., reported a drop in pipeline pressure to the
Iowa Department of Natural Resources at 4:30 a.m. Saturday. The pressure drop
occurred at 2:30 a.m. in a section of 8-inch pipe that runs under the Missouri River
from Decatur, Neb., east to Interstate 29 just west of Onawa.

Company officials were able to shut the pipeline down on both sides of the river,
estimating the maximum amount of gasoline in the pipe to be 140,742 gallons. They
had teams searching for the leak by 4:30 a.m. The company tried to verify and locate
the break on the ground, from a plane and from a boat.

By 4 p.m., they suspected the break was on the Iowa side of the river in the flood
plain, but still did not have a specific location. The company is pumping the
gasoline that remains in the pipeline into trucks. If flood water shows up as they
pump, that may help the company locate the break. If not, officials plan to send
divers to look early next week.

Natural gasoline is not natural gas. It is an unrefined light-weight liquid, clear
to light amber in color. It smells of petroleum and floats on water. It is heavier
than air. The product has likely floated on down river. Even if the gasoline is
found, it would be dangerous and difficult to recover in the turbulent flood
conditions.

The DNR notified downstream water supplies in Council Bluffs, Iowa, and Blair and
Omaha, Neb., to alert the operators of possible petroleum contamination. The DNR
also notified the Nebraska Department of Environmental Quality. The company notified
the U.S. Environmental Protection Agency and the state of Nebraska.

A second pipeline carrying propane runs in the same trench as the natural gasoline.
Company officials are using a flare to burn off propane on the Nebraska side of the
river as a precaution.

The DNR is not considering enforcement actions.