A provincial government union is urging P.E.I.'s environment minister to ensure a gas exploration company doesn't ruin the Island's groundwater.

The Union of Public Sector Employees wants Richard Brown to ensure PetroWorth doesn't carry out a procedure called fracking.

That's where millions of gallons of water, sand and chemicals are pumped into a natural gas well. The extreme pressure fractures the sandstone, enabling the gas to flow better.

But there are concerns the chemicals could contaminate drinking water. Also, the process uses a lot of water.

"It certainly shows that there's a lot of things that people need to be concerned about," said Shelly Ward, UPSE president.

"The mixture of water and chemicals that are going into the ground and that are left there, we don't know what the residual effects of that is, and has on the environment or our water."

Ward said the provincial government has given PetroWorth exploration rights to a third of the Island, without enough rules to protect groundwater.

In 2007, Corridor Resources carried out fracking on P.E.I.

No one from the province or from PetroWorth could be reached for comment.