Houston-based Plains All-American Pipeline says it has deployed 2,700 booms in response to a Friday pipeline break at a pump station about 40 miles east of St. Louis near Highland.
The company said it contained "a portion" of the 4,200-gallon spill on site before it reached Little Silver Creek, which feeds into Silver Lake. The lake is a municipal drinking water source for Highland and the nearby town of Grantfork.
A May breach at a Plains All-American pipeline near Santa Barbara led to California's largest coastal oil spill in 25 years. An estimated 21,000 gallons reached the Pacific Ocean, with tar balls washing up on beaches 100 miles away.