Executive Summary
The Goleta Water District (GWD) is currently in compliance with all State and Federal drinking water
quality standards, including the four-quarter Locational Running Annual Average (LRAA) total
trihalomethanes (TTHM) standard of 80 micrograms per liter (μg/L).
Water quality has been declining in Lake Cachuma, GWD’s surface water supply, as a result of drought
and wildfire impacts to its watershed. Increasing levels of organic matter are anticipated to exceed
GWD’s current treatment capabilities persist at high levels into the foreseeable future. Accordingly,
one of the District’s top priorities is to maintain water quality, specifically to upgrade treatment to
reduce organic matter and reduce the formation of THMs in the Corona Del Mar Water Treatment Plant
(CDMWTP) treated water and in the distribution system.
This proposed plan serves to notify the California State Water Resources Control Board Division of
Drinking Water of GWD’s intent to perform a full-scale plant test at CDMWTP of JC9450 as an alternative
to sodium hypochlorite, with the goal of reducing THM formation. Manufactured by Jenfitch, LLC,
JC9450 is a proprietary, NSF 61-approved water treatment chemical with properties similar to chlorine.
Jenfitch NSF-approved products have been used for a number of water quality improvements by other
water treatment plants, including Stenner Surface Water Treatment Plant (SSWTP) in San Luis Obispo,
California and the City of Martinez Water Treatment Plant in Martinez, California.
Jar testing of JC9450 was performed by GWD staff in October 2017 to simulate CDMWTP treatment
processes. GWD observed a 95% reduction of TTHM and a 21% reduction in the seven-day TTHM
formation level in samples that were treated with a low dose of JC9450 as an oxidizing agent in lieu of
sodium hypochlorite. Sodium hypochlorite was still used as the disinfectant.
Based on these promising results of the jar testing, GWD proposes a limited duration, low throughput,
full scale plant test of JC9450. In addition to being NSF 61 approved, the JC9450 chemical has been used
successfully at SSWTP and other plants, with one adverse impact reported: a turbidity increase at the
filters, which was overcome by renewing the adsorption capacity of the filters. GWD is heeding the
lesson of SSWTP’s experience by proposing to super-chlorinate the filters in advance of the CDMWTP
full-scale test.
A preliminary full scale plant test of up to two weeks’ duration is tentatively scheduled for January 2018.
The test will allow GWD to evaluate the efficacy of JC9450 to reduce THM levels and formation potential
and to monitor impacts to CDMWTP processes. During this test, GWD expects to operate CDMWTP at
approximately three million gallons per day (MGD) throughput. GWD also anticipates meeting the
balance of customer demand in the distribution system via groundwater production.
Full-scale plant testing will be conducted with extensive process monitoring, cooperation from the
chemical manufacturer, and routine plant sampling and monitoring by GWD Operators. If the initial twoweek test shows promising results and no adverse impacts, the District expects to prepare for an
additional full-scale testing of up to three months to allow for more comprehensive testing while
primarily on surface water. During this longer full-scale plant test, groundwater production may be suspended, and water quality changes will be monitored within CDMWTP and throughout the
distribution over a longer period to evaluate the suitability of JC9450 as a long-term treatment solution
for reducing THM formation.
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