After Years Of Testing, Water Plant May Make History

Rialto’s West Valley Water District in California will soon make environmental cleanup history. After years of testing, the district has developed a way to clean up contaminated groundwater in the Colton-Rialto water basin and send it directly to consumers.

According to The Sun, the district will be able to accomplish this task by sending water directly to customers from a $23 million specialized treatment plant at its headquarters. The plant has the ability to provide water for nearly 16,000 of West Valley’s 66,000 customers.

“Other locations are using the same technology, but they are discharging the output of the plant to groundwater or surface water,” Matthew Litchfield, interim general manager, told The Sun.

For the project to work properly, “naturally occurring microbes are placed into giant cylindrical tanks and fed acetic acid, a strong form of vinegar, which helps them grow and multiply.”

When the water from the polluted wells is introduced at the bottom of the tanks it is forced upward through a medium containing the bacteria. Once the microbes have drawn out available oxygen from the water, they go after the oxygen in the water’s nitrates.

Then the bacteria attack the perchlorate, pulling out the oxygen, and destroying it as far as being a public health threat.

“This is a harbinger of what is to come,” Todd S. Webster, a regional vice president of Texas-based Envirogen Technologies Inc., told The Sun.

For higher contamination levels, another approach was needed and the district elected to pursue using perchlorate-eating microbes.

Perchlorate is rich in oxygen, and for that quality is used as a component of solid rocket fuels, flares, fireworks and explosives, a USGS report says, according to The Sun.

In 1998, West Valley and the city of Rialto shut down several wells due to perchlorate detection.

“Some time ago, the leadership of West Valley made a decision to try and solve the perchlorate problem and not to make attorneys wealthy,” Dr. Clifford O. Young, Sr., president of the West Valley Water District, told The Sun.

In 2005, the West Valley district installed ion exchange systems on some wells with low concentrations of perchlorate. This uses a resin to pull out pollution.

The $23-million-dollar treatment plant was paid for largely with grant funding that included $10 million from Proposition 84, the Safe Drinking Water, Water Quality and Supply, Flood Control, River, and Coastal Protection Bond Act of 2006, according to The Sun.

Funding also included $2.6 million from the Santa Ana Regional Water Quality Control Board Cleanup and Abatement Account Fund and $3 million from the state Water Resources Control Board.

A small pilot project was developed and tested before moving onto building the full-scale version, which began in 2011. The final permit for the plant was granted on May 17.