ASSOCIATED PRESS — The head of the Texas Commission on Environmental Quality says he’s “absolutely” certain a chemical leak occurred to contaminate Corpus Christi’s public water supply although 115 tests have failed to show if an asphalt emulsifying agent made it from an industrial mixing tank to the water supply.

Richard Hyde tells the Corpus Christi Caller-Times (https://bit.ly/2i3wL0K ) that state and federal authorities are looking for the duration, quantity and where the leaked chemical went.

City officials imposed a water ban last Wednesday and lifted it four days later after a rush for bottled water and business and school closings. They later learned the mixing tank held the asphalt chemical.

Hyde says 12 people have complained of symptoms consistent with exposure to the chemical but water samples from those areas show no trace of it.

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