CHARLESTON, W.Va. (AP) -- An independent research group suggests sampling water in 720 West Virginia homes for a chemical that spilled into the water supply in January.
Using state taxpayer dollars, the group WV TAP already tested 10 homes in February for crude MCHM. Each house contained traces of the chemical, but the concentrations were about 675 times weaker than what federal officials call safe to drink.
The researchers say sampling 720 homes would provide a better idea of whether affected households are now chemical-free. The spill spurred a ban on using tap water for 300,000 people for four to 10 days. The impact spread across nine counties.
"Without the larger scale tap water sampling program, chemical levels in the affected area will remain unknown," WV TAP wrote in a report.
In March, the group discovered that one of the first homes in the water company's distribution still had some chemicals flowing from the tap. West Virginia American Water responded with its own tests, and found the chemical was leaving its plant's filters at a level about 2,000 times less than the CDC's safe drinking water mark.
Many researchers say the chemical won't disappear completely until the water company finishes changing its filters. That's scheduled to conclude this week, said West Virginia American Water spokeswoman Laura Jordan.
It is unclear how much additional testing would cost. The group used $765,000 from the state to test the first 10 homes, along with conducting other related studies.
Gov. Earl Ray Tomblin spokesman Chris Stadelman says the administration is awaiting WV TAP's final report before determining next steps.