Manteca has been effectively  removing TCP from municipal well water over the past decade.

Described by the state as a “potent carcinogen”, it has been detected in a handful of city wells over the years as the plume of contamination spreads hundreds of feet below ground.

Most of the city’s wells aren’t impacted.

The effective removal of the containment TCP — 1,2,3-trichloropapne — from municipal water has been a priority for the city since it was first detected in a well in 2013.

The next well that will have the TCP treatment process added is in the park serving the Yosemite Village neighborhood south of Lincoln Center anchored by Hafer’s Furniture and to the southeast of Union Road and Yosemite Avenue intersection.

The Manteca City Council last week approved moving forward with the $3.96 million project.

When completed, the city will reconfigure the baseball field as well as improve the surface of the park’s basketball court.

Council also directed staff to look at other park improvements that could be done at the same time such as installing surveillance cameras.

The above ground tanks needed for the TCP treatment process will be secured by a  wrought iron fence and surrounded with landscaping that, as it matures, will block the view of the tanks form the general public.

Extremely small traces of the chemical TCP  used in pesticides for orchard crops as well as in industrial solvents has been detected in several Manteca municipal water wells over the years.

The State of California mandatory reportable threshold is 5 parts per trillion while the federal Environmental and Protection Agency’s reporting threshold is 30 parts per trillion.

The first well TCP was detected in was in July 2013 in the Manteca  Industrial Park along Vanderbilt Circle near Main Street and the 120 Bypass.

The well at the time had 38  parts per trillion of 1,2,3-TCP.   

 To put that in  perspective, 38 parts per trillion is the equivalent of 38 drops of water diluted into 20-Olympic-sized swimming pools.

Federal environmental laws do not require any action  to be taken unless the 1,2,3-TCP contamination reaches 500 parts per trillion or 13 times higher than what was detected July 2013.
That said the state acting out of an abundance of caution in July 2017, the California State Water Resources Control Board, Division of Drinking Water, adopted a new, enforceable regulatory standard, called a Maximum Contaminant Level, for 1,2,3-trichloroporane (“TCP”), which the State describes as a “potent carcinogen” that “poses a significant carcinogenic risk when it occurs in drinking water” at low levels. 

In the latest notice posted by the city regarding TCP, it notes “our water system recently violated a drinking water standard. Although this is not an emergency, as our customers, you have a right to know what you should do, what happened, and what we are doing to correct this situation.”:

It goes on to state just one additional well — the Yosemite Village well — has been found with TCP issues.

The notice indicates:

*You do not need to use an alternative water supply  such bottled water.

*This is not an emergency. If it had been, you would have been notified immediately. However, some people who drink water containing 1,2,3-trichloropropane in excess of the MCL over many years may have an increased risk of getting cancer.

*If you have other health issues concerning the consumption of this water, you may wish to consult your doctor.

 TCP has already been detected in hundreds of water wells in California.

Manteca is among more than 100 entities that have filed litigation over the years against Shell Oil and Dow  Chemical that manufactured and sold products with TCP in them.

To contact Dennis Wyatt, email dwyatt@#mantecabulletin.com