The City of Chino will apply $25 million in state grant money it has obtained to cover roughly 43 percent of the $58 million cost of a water treatment plant to be located outside its city limits to remove trichloropropane.
The City of Chino has its own water utility division which manages the city’s water, sewer and storm drain system. While most of the Chino municipal water systems wells and other water related facilities are located in the 29.7-square mile city, some of those are on city-owned property outside the city limits such as in neighboring Ontario, Montclair, Chino Hills and on unincorporated county land along Chino’s periphery.
One such facility is the so-called “State Street Water Treatment Facility” located at 10762 Benson Avenue just south of State Street in Ontario, not too distant from Ontario’s border with Montclair.
Water drawn from wells in proximity to that treatment facility contain varying levels of different contaminants. One such contaminant that represents a serious issue for the city’s water division is the chemical 1,2,3-trichloropropane, also known as 1,2,3-TCP.
1,2,3-trichloropropane is a colorless, man-made liquid chemical that does not occur in nature and was previously used as a solvent and in paint and varnish removers as well as a chemical intermediate.
1,2,3-TCP has shown up in two of the Chino Water Utility Division’s wells, Well 12, on the southwest corner of Central Avenue and Phillips Boulevard, and Well 14 on the 10762 Benson Avenue property at the southwest corner of State Street and Benson Avenue, proximate to the treatment plant site.
That 1,2,3-TCP is present in the water drawn from Well 14 is not surprising. State Street, which lies between Holt Boulevard to the north and Mission Boulevard to the south and immediately south of the railroad tracks, runs from Ontario near Ontario Airport in the east, through Montclair and into Pomona. Along much of its length are the industrial areas of Ontario, Montclair and Pomona.
The chemical’s presence in water drawn from Well 12 is potentially explicable because 1,2,3-trichloropropane historically was also used as a soil fumigant. Well 12 is located on a property that served as a residence for the owners of surrounding agricultural land in the 1920s, 1930s, 1940s and 1950s and early 1960s and which thereafter was developed residentially.
There is scientific data to indicate that 1,2,3-TCP is a carcinogen linked to liver, kidney, and other organ tumors in animal studies.
While the federal government has not set a maximum contaminant level for 1,2,3-trichloropropane, the State of California has an enforceable maximum contaminant level of 5 parts per trillion for drinking water.
The state has a permissible exposure limit in an occupational setting of 50 parts per million or 300 milligrams per cubic meter.
Currently, the preferred treatment used on 1,2,3-TCP-saturated water is to run it through granular activated carbon filters.
The $58 million facility would provide adequate treatment capacity to rehabilitate Well 12 and Well 14, as well as to remove some other contaminants from the local water supply, including nitrates.
There are substantial threats to water in the Chino Valley.
Decades of farming activity in the Chino Valley have introduced pesticides into the soil and groundwater and the dairies in Chino which were part of the Chino Agricultural Preserve resulted in a substantial leaching of nitrates and nitrites into and through the soil into the aquifer of the Chino Water Basin. In response, the cities of Chino, Chino Hills, Norco and Ontario, in conjunction with the Inland Empire Utilities Agency, the Jurupa Community Services District, the Santa Ana River Water Company and the Western Municipal Water District formed the joint powers agency Chino Basin Desalter Authority, which operates the Chino I Desalter and Chino II Desalter facilities to purify brackish groundwater extracted from the lower Chino Basin.
In July 2010, while trenching for installation of a storm drain pipeline for a Southern California Edison facility at Chino Airport was ongoing, 51 drums of napalm buried at Chino Airport decades previously were found. Some of those drums had lost their integrity and the contents had begun to seep into the water table.
Another problem with water quality in that area consists of a plume of perchloroethylene (PCE) and trichloroethene (TCE) that originated at Chino Airport migrating south-southwest from the western end of the airport property. The plume more than a decade ago had reached a point about 7,500 feet from the airport, just south of Bickmore Avenue. There are 28 permanent wells in the area and 33 additional sample ground water collection probes that have monitored the extent of contamination and its movement. The highest level of TCE detected is 420 parts per billion. The allowable California safe drinking water standard is 5 parts of TCE per billion, such that some of the water in the basin has tested at a level that is 84 times higher than is considered safe.
Public Works Director Hye Jin Lee told the council on November 18 about the state grant for the construction of the proposed State Street water treatment facility.