West Yost was commissioned by the Central Valley Clean Water
Association (CVCWA), to evaluate whether various wastewater
treatment processes can achieve stringent water quality-based
permit limits being applied to municipal dischargers in the
Central Valley of California.
The NPDES permit assistance performed by West Yost for
the City of Vacaville included preparation of a Report of Waste
Discharge and NPDES permit application, and subsequent
negotiations with the Regional Board regarding the NPDES permit
requirements. The NPDES permit adopted was the first permit in
the State to incorporate the requirements of the Policy for
Implementation of Toxics Standards for Inland Surface Waters,
Enclosed Bays, and Estuaries of California, 2005 (SIP).
West Yost provided a facility assessment for the original design
of the 0.16 mgd, Flag City Wastewater Treatment Plant (WWTP).
This work included an evaluation of the disposal capacity of the
onsite storage pond, and an evaluation of several long-term
disposal and reuse options. Through this study, it was determined
that continued land disposal in the short-term was not feasible.
Therefore, this study culminated in the development of an NPDES
permit application and Report of Waste Discharge to allow for
surface water discharge. West Yost provided support services
throughout the permit renewal process, including negotiations
with Regional Water Quality Control Board staff, and data
analysis.
West Yost is assisting the City of St. Helena in the development
of the best compliance solution for several outstanding
regulatory issues associated with their 0.5 mgd Wastewater
Treatment Facility (WWTF), including an evaluation of the City’s
water reuse options.
West Yost was first retained by the City of Atwater (City) to
assist with the development of a formal comment submittal to the
Regional Water Quality Control Board in response to the Tentative
Waste Discharge Requirements (WDRs) for the City’s 6.0 mgd
Wastewater Treatment Plant. West Yost raised several technical
issues identified in the Tentative WDRs, many of which were
resolved through discussions with Regional Board staff. The
permitting team’s remaining concerns caused the Regional Board to
withdraw the Tentative Permit from consideration to give the City
and the Regional Board an opportunity to further evaluate some of
the outstanding technical issues.
West Yost is assisting the City of St. Helena in the development
of the best compliance solution for several outstanding
regulatory issues associated with their 0.5 mgd Wastewater
Treatment Facility (WWTF). One of the major drivers of the
proposed project is the need for expansion of the currently
available disposal operations, which include surface water
discharge to the Napa River from December through April, and land
application on property located adjacent to the treatment
facility. This project has capitalized on West Yost’s
understanding of and experience with wastewater permitting, and
includes ongoing interaction with the San Francisco Bay Regional
Water Quality Control Board.
West Yost has been providing wastewater treatment and disposal
system planning and regulatory compliance services for the City
of Lodi White Slough Water Pollution Control Facility (WPCF)
since the late 1990s. This work has included several planning and
regulatory studies related to the current and future requirements
for surface water discharge, biosolids land application, and
recycled water use on agricultural properties surrounding the
WPCF and an adjacent power plant.
West Yost recently performed a facility reliability, condition
assessment, regulatory compliance evaluation, and recommendations
plan for Mt. View Sanitary District’s Wastewater Treatment Plant
(WWTP).
West Yost completed a BOD Organic Loading Study to evaluate
the site-specific cycle average BOD loading limit that is
appropriate for the City’s land application site to prevent 1)
odorous anaerobic conditions, 2) incomplete removal of organics
in the soil profile, 3) mobilization of iron, manganese, and
other compounds, and 4) increases in bicarbonate in the soil
solution via carbon dioxide conditions.
