West Virginia American Water Co. customers living in the designated zones -- part of the areas in nine counties under a do-not-use order since Thursday -- were cleared to begin flushing their home plumbing under a proscribed process Monday, MetroNews radio network reported Tuesday.
An estimated 7,500 gallons of the chemical 4-methylcylohexane methane, used in the coal-cleaning process, leaked from a storage tank at Freedom Industries and into the Elk River in Charleston Thursday. More than 300,000 residents in nine counties were advised not to use their tap water because of concerns about possible contamination.
Four zones in the Charleston area were cleared on Monday and two were added Tuesday, and included much of the downtown from the Elk River, as well as the Capitol and several of the city's neighborhoods, the water utility said.
"We're finally at a point where the do-not-use order is being lifted in certain areas," Gov. Earl Ray Tomblin said Monday.
"Only customers located within zones that have been lifted should begin flushing. If we have problems with pressure in the system, we will not be able to open up additional zones until those pressures are restored," Jeff McIntyre, West Virginia American Water president, said Monday.
He said the timetable for fully restored water service for all customers depends on chemical tests in individual zones and demands on the system as more homes and businesses resume normal water usage.
Officials with the West Virginia National Guard said tests confirmed chemical levels were low or non-existent in many parts of the system by Monday, MetroNews said.
Water company officials said water quality was being monitored in Huntington as the chemical migrated downstream, but so far results confirmed only trace amounts of the chemical entering and exiting the treatment plant there.