A Health Canada-funded study found higher than normal levels of certain chemicals in several wells close to the Cache Creek landfill. (CBC)

Three wells currently in use near the Cache Creek landfill in the south central interior of B.C. contain higher than normal levels of chemicals, a study has found.

According to the Health Canada-funded study, chemicals such as arsenic could be leaking from the Cache Creek landfill into groundwater and a nearby river.

The landfill is owned by Metro Vancouver and is the site where up to half a million tons of garbage from the Lower Mainland is dumped each year.

The study was carried out by EcoGen, a North Vancouver company specializing in environmental contamination, on behalf of a First Nations group in the area. It was initially intended to obtain baseline data in case there were problems in the future.

"We had no idea when we started this study that we would actually be finding a significant problem," said Michael Easton, president of EcoGen.

EcoGen tested nine groundwater sites and seven locations on the Bonaparte River, where Cache Creek is located, and found arsenic and selenium at levels higher than B.C. drinking water standards allow.

Representatives at Wastech, the company that runs the landfill, said they have not seen the report yet, but contends it does regular groundwater testing and there has never been a problem with leaching chemicals.

Easton said one of the ways to detect that a landfill is leaking is to test for chemicals such as Poly-brominated dimethyl ethers, or PBDS, which are common in products like computers and upholstery but not in nature.

"We know that they are becoming the new worst contaminant in our environment and they are very, very prevalent in landfills," said Easton.

He said those chemicals were found six kilometres from the Cache Creek landfill and just two kilometres from the main water supply of the Ashcroft Indian Band.