Measured chemical levels are declining in water samples, but Kanawha Valley residents are still likely "several days" away from being able to use tap water, government officials said Saturday.
"All the numbers are trending in the right direction," said Lt. Col. Greg Grant, chief of a National Guard civil support team that's running the tests.
About 300,000 residents have been told to use water only for flushing toilets since a Thursday chemical spill contaminated the Elk River and the water supply of eight West Virginia counties, and part of a ninth.
The chemical, "Crude MCHM," is used in coal processing and leaked out of a 35,000-gallon tank owned by Freedom Industries, a chemical distributor based in Charleston and Nitro. A retaining wall surrounding the tank, supposed to serve as a failsafe, was scheduled for $1 million in repairs.
The U.S. Centers for Disease Control and Prevention has said that levels of the chemical must be below 1-part-per-million for safe use, but it is not clear how that figure was derived.
Grant said that it initially took them 24 hours to develop a method to analyze the chemical in the water, but they have gotten much more efficient, reducing the time it takes to test one sample from 46 minutes to 18 minutes.
On Saturday afternoon, Jeff McIntyre, president of West Virginia American Water Company, said that they are testing water around the clock to determine the concentration of Crude MCHM but he refused to release the results of those tests.
He said West Virginia American's system, by far the largest water utility in the state, was too big to judge with a limited number of samples.
At a press briefing late Saturday evening, the Tomblin administration reversed course and released water sampling results.
Officials said the most recent tests showed some results that were below the 1-part-per-million level -- 0.75 and 0.62 for example -- but that others had spiked above that amount. One fire hydrant recently tested at 1.39 parts-per-million.
A sheet of test results provided by Tomblin's office showed that eight out of 18 recent test results tested above 1 part per million.
Initial tests, conducted prior to the National Guard's involvement, showed levels as high as 2 to 3 parts per million.
"We're trending in that direction," Grant said. "we initially had some numbers that were 2 to 3 parts per million. Now we're down below one part per million,"
Grant said officials would conduct more than 100 water tests overnight and the same amount throughout the day Sunday.
Dorsey said the cleanup is working.
"The reason the numbers are going down is we believe less of the material is getting into the water," Dorsey said. "We have cut of the source of the leak, the tank. There is still material under the concrete and the soil. We've taken aggressive measures on the shore line below the site."
Public health officials said they need to see 24 straight hours of results below 1 part per million before the water company can begin flushing the system.
"These individual samples are like a puzzle piece and we have a bunch of puzzle pieces but we don't have a picture yet," McIntyre said.
McIntyre said that once water service is returned, the company would offer residential customers a credit for 1,000 gallons of water to allow them to flush contaminated water through their pipes.
Department of Health and Human Resources Secretary Karen Bowling said 73 people had gone to area emergency rooms and five have been admitted to hospitals with chemical-related symptoms.
"I think it's valid that people are beginning to understand that if you have signs and symptoms, we certainly want you to seek medical attention," Bowling said. "But we also want people to understand that, again, if everyone followed the precautions as indicated, ... then we believe there will be less and less people reporting with irritation -- eye irritation, nausea and vomiting."
Mike Dorsey, with the state Department of Environmental Protection, said they now think 7,500 gallons of Crude MCHM leaked into the river.
That's a big increase from previous estimates, which pegged the leak at 2,000 to 5,000 gallons.
Dorsey said the chemical leaked out of a one-inch hole in the 35,000-gallon steel tank.
The chemical has stopped leaking out of the tank itself but could still be in the surrounding soil, Dorsey said.
"You can't see anything coming out anymore, but just given my experience, I would say there's some in the ground," Dorsey said. "I'm guessing there will be some coming out of that bank for some time now...we've cut off the source. There is still material under the concrete and in the soil."