On Thursday, an estimated 300,000 residents of nine counties in West Virginia were told they could not use or drink their tap water after a chemical used to wash coal of impurities spilled from a holding tank into the Elk River. The spill prompted Gov. Earl Ray Tomblin to declare a state of emergency, and 9-1-1 received more than 1,000 calls in the hours after a spill, with four or five people transported to the hospital by ambulance. According to the National Library of Medicine, repeated or prolonged exposure to the chemical, 4-Methylcyclohexane Methanol, can “cause headaches, irritation of the eyes, nose, and throat, and can also cause a skin rash.”

On Friday, West Virginia American Water Co. held a press conference to share what they knew so far about the spill. Unfortunately, they still don’t know much about the spill or the chemical involved.

1. No one knows when water will be safe to drink again. “I can’t ballpark it because I don’t know,” Jeff McIntyre, president of West Virginia American Water Co. said at the conference. The entire water system will have to be flushed and tested, and though the Elk River was the water source immediately impacted by the spill, McIntyre said that the spill impacts the entire distribution of the water system — sending water to a total of 1,500 miles in the area.

Charleston Mayor Danny Jones said that he had hoped to find out a timeline for when residents could use their tap water again at the press conference.

“This has been devastating to the public at large and the people that live in our city,” he said. “The folks out there that just work every day and go to work and who are just regular citizens, they would like an end to this.”

2. No one knows when the leak started or how much has leaked into the Elk River. It was complaints of an odor coming from communities near the river that triggered city and county officials to investigate. They found the source of the spill at 4 p.m. Thursday, but had no way of knowing how long the chemical had been leaking. McIntyre also said he didn’t think the chemical was still leaking, but didn’t know the current status of the spill for sure. According to a Department of Environmental Protection spokesman, the state is “confident that no more than 5,000 gallons escaped,” but only knows that “a certain amount of that got into the river. Some of that was contained.”

3. The water company has had no contact with Freedom Industries, the company that manufactures the spilled chemical. According to McIntyre, the company provided no notice of the spill and hasn’t been in communication with the water company since.

4. There is no standard process for testing the toxicity of the spilled chemical in water. When the water company found out about the spill, it was originally told it was a different chemical than the 4-Methylcyclohexane Methanol that had spilled into the water. But even when the company found out what the chemical was, it couldn’t answer many questions about it. “This not a chemical that’s typical to be in water treatment process,” McIntyre said during the press conference.

5. It’s unclear just how dangerous the diluted chemical is to drink or breathe.According to McIntyre, toxicologists have said that people would have to eat a large amount of the chemical to cause harm, but still, McIntyre said he didn’t know how the chemical had affected the safety of the water. “We don’t know that the water’s not safe, but I can’t say it is safe.” However, Kanawha County Deputy Emergency Services Director C.W. Sigman said during the press conference that the chemical is hazardous, which lines up with the National Library of Medicine information on the chemical.

6. The chemical may have leached into the soil. McIntyre said that when the containment in the chemical holding tank failed, the chemical traveled over land and into the Elk River. That could have caused some leaching, he said.