MOSES LAKE - The state Department of Ecology is seeking public comment before it removes a natural gas meter station on Wheeler Road from Washington's hazardous sites list.

Mercury was found in soil and gravel at Northwest Pipeline's Moses Lake Meter Station in 1990 during a site assessment and placed on the state's hazardous sites list, according to an Ecology statement released Monday.

The list ranks contaminated sites in the state on a scale of one to five. One represents the greatest potential threat to human health and the environment, while five represents the least potential threat.

The Moses Lake site ranked a three, according to the news release.

The site is located at 13579 Wheeler Rd. NW and is made up of two meter stations that regulated and metered the distribution of natural gas, according to the release. The two stations, known as the Moses Lake meter station and the U&I Sugar meter station, were adjacent to each other within a fenced enclosure.

Ecology officials said the main source of contamination was likely caused by mercury releases during equipment maintenance, according to the release. Mercury releases from thermowells used to measure gas temperatures was another likely source of contamination.

Since the level of mercury in the soil exceeded state standards at the time of the assessment, site cleanup was deemed necessary.

Northwest Pipeline entered Ecology's voluntary cleanup program, which allowed the company to perform the cleanup independently from the agency.

Fifteen drums of gravel and soil were removed from under and around the meter stand and associated piping at the Moses Lake meter station, and four drums of gravel and soil were removed from under the U&I station.

About 132 tons of soil were excavated and transported off-site for disposal in 2011, according to Ecology.

Follow-up sampling in 2011 indicated all contaminated soil was removed. According to the release, no further actions are required at the site.

The Moses Lake meter station was retired in 2000 and the current Moses Lake meter station is located in the former U&I meter building.

According to Ecology spokesperson Brook Beeler, the agency plans to remove the Moses Lake site from the hazardous sites list after public comment is received and considered.

"We're proposing the site comes off the list as being hazardous," she said Monday.

Beeler said the agency believes the site is no longer a threat to human health or the environment.

However, she said Ecology wants to make sure there is no public concern about the site's safety before the agency moves forward with removing the site from the list.

"The public comment period asks, did this voluntary cleanup company do a good enough job," she said.

According to the news release, residents have until April 15 to send in their comments. Documents related to the cleanup of the Moses Lake site can be viewed on the agency's website at https://fortress.wa.gov/ecy/gsp/Sitepage.aspx?csid=2354.

Comments should be emailed to patti.carter@ecy.wa.gov.