In recent days, West Virginia residents increasingly have been asking why the state Department of Health and Human Resources or the National Guard are testing water for MCHM only at the water treatment plant, at fire hydrants and in some public buildings, such as schools.
Outside experts have expressed concern that the MCHM and other chemicals from the leak could have been absorbed by home plumbing systems, where it could continue to leach into water -- even if in very small amounts -- for some undetermined amount of time. Whelton compares the pipes to a sponge, in which the chemicals would be quickly absorbed, but perhaps not so quickly expelled over time.
U.S. Environmental Protection Agency officials said Wednesday they have a study that disputes this theory, but they have not released a copy of the study. EPA regional drinking-water chief Bill Arguto suggested a reporter could get a copy from West Virginia American Water. The water company has not responded to a request for the study.
A West Virginia University scientist who also received a National Science Foundation grant to study the Elk River leak said Thursday she agrees with Whelton that it's not clear yet how the leak impacted home piping and tanks.
"We do not know how these chemicals will interact with different plumbing materials," said Jennifer Weidhaas, an assistant professor of civil and environmental engineering.
Before the governor's change of position Wednesday, Tomblin administration officials had rejected the idea of testing homes by saying there was no way they could possibly test all potentially impacted homes.
"There's not a hesitancy to do it, but there's a cost to it," Tomblin said Wednesday. "Trying to test a hundred thousand customers could be in the tens of millions of dollars."
During a breakfast with representatives of the West Virginia Press Association, Kessler suggested Thursday the state could test three or four homes in each of West Virginia American Water's 24 distribution districts. By one estimate of $675 per test, Kessler said, that would cost the state only about $65,000.
"If we would go out and do that and they would come back clean, it would go a long way toward restoring the public's faith in the water system," Kessler said.
Asked how reliable testing fewer than 100 homes would be scientifically, Kessler conceded that he is not an expert and said the state needs to find experts who can help design an appropriate and properly sized study.
"I'm not the expert in the subject area, but I think it would be a start to do something," Kessler said. "I don't know what that study sample needs to be. If we had to do 2,000 to make it statistically sound, then so be it. We need facts."
Dr. Tanja Popovic, director of the U.S. Centers for Disease Control and Prevention's National Center for Environmental Health, said any decision to test homes must be made carefully.
"That decision needs to be made with a little bit more thinking and deciding what kind of data we're going to have, what validity we're going to have," Popovic said. "One of the things we all have to do is be very honest about what we do know, what we do not know, and not promise to do things where expectations or outcomes or results are just so that we don't know whether we can do it.
Popovic added, "Conducting studies without having the knowledge that there will be a statistical power, that there will be an ability to make a conclusion, is not advisable."
Whelton said he has hesitated to estimate how large of a study is needed or how many homes should be sampled. State officials need to consult with outside experts, Whelton said, to figure out exactly what they hope the study will find out, and then design the study to meet those goals.
For example, he said, the study needs to make note of the types of pipes in each house, and when the plumbing was flushed, so that experts can draw conclusions about how the chemicals interacted with plumbing systems and how flushing impacted the chemical's presence in homes.
"I really don't think you need to test thousands of homes," Whelton said. "You're probably looking at hundreds. It can be done."
Whelton added, "The approach the governor is now moving toward is excellent. It's a step in the right direction. The next step is to figure out the breadth and depth of this examination."
Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.