Cal Am test well could be turned back on next week, officials say
By KELLY NIX
6.26.15 Carmel Pine Cone Page 5A
THE HYDROGEOLOGISTS who investigated the drop in groundwater levels near California American Water’s desal test well in Marina have concluded that the cause was probably due to agricultural pumping and not the company’s test operation.
On June 5, Cal Am turned off the test well after the hydrogeologists determined that the water level in a nearby monitoring well had dropped more than a foot. But in a follow-up report released June 22 that was also sent to coastal commission executive director Charles Lester, the group backed its original theory that the dip in groundwater level is not a result of the test well.
The data “shows that the regional trends and fluctuation cycles in [the monitoring well], are most likely due to inland pumping and/or seasonal fluctuations, and are expected to continue,” the report said.
The conclusion is good news for Cal Am and the entire Monterey Peninsula, since a drop in groundwater levels could have meant that the test well was drawing too much fresh water from the Salinas Valley, and not enough seawater from the Pacific Grove.
Cal Am spokeswoman Catherine Stedman told The Pine Cone that the company expects to hear from the coastal commission next week. “They could give us the go-ahead to turn the well back on, or could request more data,” she said.
The test allowed the hydrogeologists to collect more data while the test well was turned off, a crucial step in determining the reason for the groundwater dip. “If the test well caused the drawdown, you would expect to see a rebound in inland groundwater levels” when the pump was turned off, Stedman explained. “We haven’t seen that.”
The hydrogeologists also concluded that “even under a worst case scenario relating to factors/causes of the regional water level
declines and slight changes in the downward trend of those declines (i.e. not caused by inland pumping or outside influences), it seems clear from the data collected so far that if there is any drawdown [at the monitoring wells] — it is less than 0.5 feet and probably closer to 0.2 feet to 0.3 feet.” As a condition of the coastal commission permit issued to Cal Am for the test operation, the company must stop pumping from the well if the water level goes below 1.5 feet. Cal Am opted to turn it off before it got that low, however.
Given the coastal commission’s permitted drawdown of 1.5 feet, the “water levels are well within the allowable limit,” according to the hydrogeologists. Though Cal Am wasn’t required to turn off the test well, Stedman said the move was done out of caution. “Everyone is exercising caution to ensure the test proceeds according to the permit conditions, the basin is protected, and that the test period yields valuable and accurate information,” she said.