PLS is stored in a stainless steel lined concrete tank at the ASARCO Ray Mine. During construction, the tank was inspected by several techniques but approximately 35 leaks were detected and attributed to defective and substandard welds. These were repaired, retested and passed inspection, but after the tank was put in service, it began to leak again. Bowman was asked to inspect and catalog the weld where leaks developed and to work with a specialized welding firm to implement a plan to repair the tank permanently.