Researchers at UC Riverside have found several wells are polluting groundwater in central Cherry Valley, the city of Beaumont announced Thursday.
"The evidence suggested that human waste is entering the groundwater system in unincorporated Cherry Valley," a city announcement stated.
The UCR findings are in a 93-page document dated Feb. 3 and titled:
"Final Report: Water Quality Assessment of the Beaumont Management Zone: Identifying Sources of Groundwater Contamination Using Chemical and Isotopic Tracers"
A public meeting will be held next week to discuss the UCR report.
"We are concerned that development outside the city could be impacting our water supply in Beaumont," Beaumont Mayor Roger Berg said in a prepared statement.
The UCR water quality report sampled 40 wells and surface water in 11 locations in Beaumont and Cherry Valley, city officials said.
"In Cherry Valley, the report found elevated levels of nitrate in the drinking water supply. Each year, about 30,000 lbs. of nitrates from Cherry Valley’s septic systems end up in the area’s groundwater supply," the city's announcement stated.
"Nitrate is one of the most common groundwater pollutants in rural areas and comes largely from fertilizers and septic systems. The report also found that nitrate levels in Cherry Valley could decline by as much as 30 percent if septic systems were phased out and a sewer system was installed."
In the past, the Beaumont Cherry Valley Water District has proposed a sewer system for the unincorporated area, city officials said.
Riverside County presently has a moratorium on new, private septic systems - unless those systems remove 50 percent of nitrogen in the waste, city officials said.
Within Beaumont city limits, UCR scientists found the wastewater treatment plant removes a "large majority" of nitrates from the sewage and the water flowing through city sewers.
The UCR report introduction begins:
"Nitrate contamination from human activities adversely affects both surface and groundwater in the United States, however determining sources of nitrate is often difficult due to non-point pollution sources and complex groundwater systems within watersheds.
"A prior study (Wildermuth 2007) identified elevated nitrate levels in some groundwater wells within the Beaumont Management Zone (BMZ) in Riverside County.
"Subsequent action by the Riverside County Board of Supervisors placed a moratorium on new on-site waste disposal systems (i.e., private septic systems) unless they were designed to remove 50% of the nitrogen in the effluent stream.
"The . . . Board of Supervisors formed the Ground Water Quality Evaluation Committee (GWQEV) and directed them to review technical data on groundwater quality and express their concerns regarding groundwater regulation in the Beaumont Management Zone.
"The Committee disputed the findings of the Wildermuth 2007 report and has identified potential shortcomings in sampling design and project execution (GWQEC 2009).
"In the Committee's report to the Supervisors dated June 15, 2009, they make the following findings and recommendations:
"1. Findings: The Wildermuth report titled: Water Quality Impacts from On-site Waste Disposal Systems in the Cherry Valley Community of Interest March 2007 Wildermuth Environmental Inc. had parameters that were too narrowly focused; used well water sources located in close proximity to on-site wastewater disposal systems and used exaggerated build out approximations.
"Recommendation: An independent third party study conducted by someone other than Wildermuth Environmental, who conducted the initial report, is needed to evaluate this perceived regional issue.
"The study should evaluate beyond those areas studied in the initial report, consider reasonable build-out projections and consider other possible sources of groundwater contamination such as septic systems in the Cherry Oaks Tract and beyond to the Hidden Meadows Tract area and the surrounding communities including the City of Beaumont."
To view the complete UCR report, please visit www.rivcoeh.org.
The Beaumont Cherry Valley Water Quality Committee will meet at 6 p.m. Monday Feb. 27, 2012 at the San Gorgonio Pass Water Agency, 1210 Beaumont Ave.