Investigators now know what caused a chemical leak earlier this month at the Port of Catoosa.
Officials with Solkatronic Chemical blame the incident on human error and a change in the manufacturing process. They say a valve on a canister of arsine was mistakenly left closed which led to over pressurization.
More than one hundred people were sent to area hospitals because of the leak. The U.S. Occupational Safety and Health Administration will review the companyâ€™s findings.