The age and history of Colfax Avenue tells officials that the long road has pockets of contamination. But who knows how much and how bad?

The U.S. Environmental Protection Agency has awarded the Colfax Mainstreet Coalition a $900,000 grant to help find the answers and determine the best course of action for cleanup along a 15-mile stretch of the street.

The coalition includes Denver, Lakewood and the Denver Urban Renewal Authority.

Although not the only cause of contamination, former gas station and dry-cleaning locations will be targeted for assessment.

DURA officials estimate there are 300 contaminated sites in the city along Colfax. The Denver stretch alone includes 136 gas station sites and 93 dry cleaners that were open along the city’s main drag from 1926 to 1980.

Lakewood officials don’t have an official estimate for the number of trouble spots on their part of Colfax.

“This is not cleanup money. These are funds which will be used to identify where problems may exist, helping landowners,” Lakewood Mayor Bob Murphy said.

Those targeted contaminated areas are referred to as “brownfields.”

“North Lakewood is one of the oldest parts of the city,” Murphy said. “There was a lot of auto-related use along Colfax, including dealerships and gas stations, which may still have underground tanks.”

The money will be used immediately for site identification and assessment.

In order for redevelopment to occur along West Colfax from Yosemite Street in Denver on the east to Indiana Street in Lakewood on the west, brownfields must be located and cleaned up, officials said.

DURA executive director Tracy Huggins said the fact that there were some targets already identified for assessment helped the coalition land the EPA grant.

The coalition requested $1 million.

EPA spokesman Richard Mylott said the $900,000 grant is one of the largest awarded for contamination assessment.

“For many years, Colfax was the only east-west corridor through Colorado, so it would make sense there would a good number of gas stations along the way,” Mylott said.

Because Colfax is so old and changed so frequently through the years, property records will have to be pulled to determine areas that may require attention, but targets are ultimately up to the coalition, Mylott said.

“My guess is West Colfax and Sheridan would be a location, and there have also been talks about the old St. Anthony’s (Hospital) site,” he said.

Huggins said most businesses do their own environmental assessments when they are interested in a property, a “burden” that she said she hopes the coalition’s assessments will eliminate.

Ryan Parker: 303-954-2409, rparker@denverpost.com or twitter.com/yhRyan