Page 85 - Yucaipa Valley Water District
P. 85
Workshop Memorandum 18-066
Date: February 13, 2018
From: John Wrobel, Public Works Manager
Subject: Overview of the Total Dissolved Solids (TDS) Discharge Limitation Change to the
Class I Significant Industrial User Discharge Permit Issued to Sorenson
Engineering, Inc. - Permit No. CP-001-03
The District issues permits to significant industrial users (SIU), which outlines the discharge
limitations of the facility. These limitations include byproduct chemicals from production and
manufacturing processes that can contain chemicals such as copper, lead, nickel, other heavy
metals, and Total Dissolved Solids (TDS).
Sorenson Engineering is one of the District’s permitted SIU’s and is requesting an increase to
their TDS limitation. Sorenson’s production has increased and their current TDS limitation is
limiting their sewer discharge. Currently the TDS limitation is 106 lbs/day and Sorenson is
requesting the limitation be increased to 170 lbs/day.
On March 11, 2013 the District requested from the California Regional Water Quality Control
Board (RWQCB), an increase to the TDS limitation. At that time the TDS limit was 719 mg/L and
the request was to increase the limit to 1,523 mg/L.
On July 17, 2013 the Regional Board approved the request.
District Staff is recommending the TDS limitation for Sorenson Engineering be revised from 106
lbs/day to 200 lbs/day.
Yucaipa Valley Water District - February 13, 2018 - Page 85 of 100
