A Burnaby city councillor is accusing B.C.'s Ministry of the Environment of playing politics with an ongoing oil leak from a Burrard Inlet oil refinery by not collecting samples from the site.

Chevron Canada Limited discovered oil seeping into the inlet in April, but after nearly eight months of testing the company still doesn't know exactly where it's coming from, why it's leaking and how much has made its way into the ecosystem.

The company says it's concerned about the leak and is co-operating with government officials.

"The site is proving to be very challenging," said Chevron spokesman Ray Lord. "We also continue to work with the designated authorities who are monitoring our progress on the clean up activity."

Lord said the company is working under difficult circumstances to clean up the leak.

"We're equally as frustrated with the progress this is taking. The efforts to identify a source within the refinery of any new current contributing sources are ongoing. We're working with a refinery that's actually functioning. it's a heavy industrial site so drilling wells and sampling within the site is challenging," said Lord.

Source of leak not identified

But area residents and environmentalists doubt the company's findings and they're not the only ones asking questions

"The frustration has been not to find a source, not to find a resolution," Burnaby engineering director Deepak Dattani told CBC News.

'Litigation isn't always the most appropriate manner to ensure environmental quality is maintained and restored.—Statement issued by the Ministry of the Environment

"We've asked Chevron what's the quantity that been released and we've not had an answer to date."

Chevron maintained in April that the oil leak is small -- about 100 millilitres, or seven tablespoons, per day. The company also said the leak results not from flaws at the facility, but from an historical seep from the ground. But none of the data appears confirmed.

Burnaby city councillor Dan Johnston said that the province, as the regulator, has to step up with answers.

Samples not collected

Johnston also wants the ministry to explain the meaning of an internal environment ministry email obtained under a Freedom of Information request by the Burnaby Now newspaper.

In the email Ministry staff overseeing Chevron appeared to have made the decision not to collect samples for investigative purposes, so as not to "compromise a cooperative working relationship with Chevron."

"The ministry seems to make its priority on politics rather than human need," said Johnston.

"Chevron's corporate image seems to be impacting the ministry's decision and I think that's pretty scary."

The ministry did issue a written statement on Monday evening, saying it has chosen to work collaboratively with Chevron since "litigation isn't always the most appropriate manner to ensure environmental quality is maintained and restored."

With files from the CBC's Priya Ramu