City officials issue advisory following water tank explosion investigation

City officials are also reassuring Lemoore residents that the city’s water continues to be safe to drink.

In the advisory issued by Lemoore City Manager Nathan Olson, the June 21 incident On June 21, 2021, was “an unfortunate and very preventable incident” when a 1.5 million-gallon-water tank exploded. This tank had been in service for many years without problems or incident,” stated Olson in his release.

According to the advisory, the contractor’s employee failed to perform an essential and required safety-check procedure before performing hot work (welding) on the tank. The advisory states that “proper monitoring of the headspace would have alerted the contractor of a condition that existed at a time when he must not perform welding.” 

The city's water tank debris the day after the 1.5 million gallon tank exploded, killing a contractor working on the tank.

Gary Freinstein/Feinsteinfotos

As a result of the City’s ongoing investigation into this incident, local officials are issuing this advisory warning:

• First, people doing plumbing work on water systems or in confined spaces containing municipal water must test the area for the presence of gas before performing work. This must be done as a matter of standard practice when cutting pipe, working in confined spaces with headspaces, or exposing any unknown atmosphere to an ignition source, such as “hot work” (anything that creates a spark or significant heat-producing activity.) 
• Second, industrial facilities with water-holding tanks must check the headspace for the presence of gas and ensure that active-monitoring electronic probes are de-energized or monitored in relation to the gas levels in the headspace; and, before performing any “hot work” associated with this type of equipment and environment. 
• Third, the water is safe to drink as the EPA and California Department of Drinking Water do not require methane testing, the gas identified to have been involved.  After all, a bit of methane comes from us after consuming gaseous foods. The guidance with this advisory is to ensure residents that the water is safe to drink but requires additional steps to maintain water systems.  People must test the work environment atmosphere before performing “hot work.”  

City officials are in the process of getting the town’s new water systems tested and approved by the state. City officials way the water is safe to drink and requires no additional treatment.