State of California s23

STATE OF CALIFORNIA

CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD

SAN FRANCISCO BAY REGION

STAFF SUMMARY REPORT (Ken KatenLinda Rao)

MEETING DATE: JULYNovember 28, 2001April 1616, 2003

ITEM: 1895.A.

SUBJECT: Cities of San Jose and Santa Clara, Water Pollution Control Plant, Santa Clara County- Hearing to Receive Testimony on Reissuance of NPDES Permit

CITY OF MILLBRAE, WATER POLLUTION CONTROL PLANT, MILLBRAE, SAN MATEO COUNTYNOVATO SANITARY DISTRICT, NOVATO, MARIN COUNTY – Reissuance Amendment of NPDES Permit

CHRONOLOGY: May and June 2003 – NPDES Permit Reissuance Status Report

to the Board

June April 1994May 25, 19991998 – Permits Rreissueed

June 1993 – Permits Reissuedd

January 1995 – Permit amended

DISCUSSION:

The Discharger owns and operates the San Jose/Santa Clara Water Pollution Control Plant which provides tertiary treatment of wastewater from domestic, commercial and industrial sources from the cities of San Jose, Santa Clara, and Milpitas; County Sanitation District 2-3; the West Valley Sanitation District including Campbell, Los Gatos, Monte Sereno and Saratoga, and the Cupertino, Burbank, and Sunol Sanitary Districts. The Discharger’s service area has a present population of about 1.3 million.

Novato Sanitary District (District) owns and operates two wastewater treatment plants, the Ignacio Treatment Plant and the Novato Treatment Plant. The treatment plants use a combined outfall into to the intertidal mud flats of San Pablo Bay. adjacent to the former Hamilton Air Force Base. This discharge is classified as a shallow water discharge. During the discharge season (September 1 – May 31) annually) the District discharges an annual average dry weather flow of about 5.4 million gallons a day of fully treated, disinfected, dechlorinated wastewater through a multi-port diffuser about 950 feet offshore. Between June 1 and August 31, annually, the effluent is held in reclamation ponds for sprinkler irrigation on District-controlled pasture lands.

In 1999, the District petitioned their permit to the State Board, and it is currently in abeyance.

In 2002, the District requested certain amendments to the existing NPDES permit. The amendments requested by the District are consistent with NPDES permits adopted for other, similar treatment plants. With this permit amendment the District plans to withdraw their pending petition at the State Board.

Process and Schedule

Staff began negotiating the three South Bay permits through the WMI stakeholder process more than a year ago through participation in over 25 meetings, two administrative drafts of NPDES permits for WMI review and additional meetings regarding discharger specific issues and complex technical topics. Board staff released the Tentative Order for public comment in late June with the comment period ending in late July. Board staff plans to bring the Tentative Order for the Board’s consideration at the August Board meeting.

Significant differences between the 1998 Permit and the 2003 Permit (Tentative Order) are illustrated in Table A. Major issues that have been resolved include the following:P

Mercury Mass Limits:

The same mercury mass limits have been in the South Bay permits since early 1990. We are revising the mercury mass limits for this permit reissuance using the same statistical approach as in similiarly, recently adopted permits.

The new proposal to address interim mass limits include a mercury interim mass limit effective only during the dry weather, aggressive pollution prevention efforts, and implementation of a watershed-based mercury study.

The new interim limits are much lower than the current limits (as detailed in Table X), this is a reflection of improved plant performance, effective pollution prevention, and better sampling and analysis methods.

Table X

Facility / Current Mercury Mass Limit (kg/year) / Proposed Interim Mercury Mass Limit (kg/year)
Cities of San Jose and Santa Clara / 32 / 0.72
City of Sunnyvale / 25 / 0.12
City of Palo Alto / 11 / 0.31

The South Bay Dischargers may propose alternatives to the proposed interim mass limit, such as a mass trigger paired with watershed-based mercury studies (i.e., treating first flush stormwater from sites contaminated with mercury, advanced pollution prevention at dentist offices, and abating the production of methylmercury from treatment plant processes).

Copper and Nickel Limits:

At present, Dischargers have agreed to the inclusion of effluent limits in the permits under the condition that with new information, the Board will reevaluate the need for effluent limits for copper and nickel.

South Bay Habitat Issues:

This permit amendment proposes the following:

1. re-evaluates the need for effluent limits for copper, nickel and mercury based on recent effluent data and the SIP;

2. re-calculates final water-quality based effluent limits for copper and mercury based on the SIP;

3. omits the nickel effluent limit as no reasonable potential was triggered;

4. gives a new performance-based effluent limit for mercury based on the 2001 Pooled Mercury Staff Report;

5. moves the compliance point for ammonia to the combined outfall to be consistent with how other water-quality based effluent limits are monitored.

Since January 2003, staff has worked to coordinate meetings with the Discharger, U.S. Fish and Wildlife Service, CAalifornia Department of Fish and Game, environmental groups and interested parties to bring closure to historical mitigation required of the City of San Jose from previous State Board Remand Order and Regional Board Resolutions.

Because the Moseley Tract was found unsuitable for salt marsh mitigation, the Discharger submitted a general proposal for an alternate wetlands mitigation project. This proposal was found suitable to USFWS and CDFG. The Discharger plans to work with resource agencies to finalize details of an agreement before permit reissuance. In this Tentative Order Board staff have written findings requiring the Discharger to continue meeting with USFWS, CDFG, and Board staff to finalize details to fund the purchase and restoration of an alternative salt marsh mitigation project within one year from the date of permit reissuance. Board Staff will continue to hold meetings between the Discharger and the resource agencies to ensure a permit consistent with the Endangered Species Act. Board Staff expects to present a resolution for an alternate wetlands mitigation project to the Board soon, for its adoption.

The attached permit amendment proposes final effluent limits for copper and mercury, and interim effluent limits for these pollutants. It also continues the current permit’s mass discharge limitation for mercury. Finally, it changes the monitoring point for compliance with the ammonia effluent limitation from the individual plants’ discharges to the combined outfall. The attached permit amendment also increases the monitoring frequency for total suspended solids in effluent and influent from once per week and three times per week, respectively, to five times per week in both influent and effluent, increases the monitoring for biochemical oxygen demand (BOD) in influent from once per week to three times per week, and decreases the monitoring frequency for settleable matter from five times per week to monthly.

The City of Millbrae, Water Pollution Control Plant, currently processes an average dry weather flow of about 2.2 million gallons per day (MGD) of treated wastewater. The present service area population is approximately 22,000 within the City of Millbrae. Fully treated and disinfected wastewater is discharged into the North Bayside System Unit (NBSU) joint force main, thence to the NBSU dechlorination facility in South San Francisco and discharge through the NBSU outfall. Dechlorinated combined effluent is discharged into Lower San Francisco Bay northeast of Point San Bruno through a submerged deep water diffuser located 5,300 feet offshore at a depth of 20 feet beneath mean lower low water.

The attached Tentative Order proposes effluent limitations for the following pollutants: copper, lead, mercury, nickel, zinc, cyanide, TCDD equivalents (dioxin and dioxin-like compounds), tetrachloroethylene, bis(2 ethylhexyl)phthalate, 4,4-DDE, dieldrin, and PCBs. Interim limits are proposed for copper, mercury, TCDD equivalents, cyanide, tetrachloroethylene, bis(2 ethylhexyl)phthalate, and PCBs. The proposed permit has fewer toxic effluent limits than the previous permit because no reasonable potential was found for other pollutants using the State Implementation Policy methodology.

Written cComments were submitted by the City of Millbrae Novato Sanitarythe District, and wand the Bay Area Clean Water Agencies. Most of the comments are similar to those for the permits considered by the Board in recent months. We have responded to them in the Response to Comments.

RECOMMEN -

DATION: Receive public testimony for Board’s consideration and action in August

File No. 2159.50222189.8014 (LRKK)

Appendices: Tentative Order

Table A: Appendices:

A.: Tentative Order

B. Fact Sheet

C. Comments

D. Response to Comments

E. Facility Location Map Differences Between the 1998 Permit and the 2003 Permit (Tentative Order).

Table A: South Bay Mercury Mass Limits.

Table A: Differences Between the 1998 Permit and the 2003 Permit (Tentative Order).

1998 Permit

/ 2003 Permit (Tentative Order)
Applicable Regulations and Policies / 1995 Basin Plan,
WQ Order 90-5,
Federal Regulations / 1995 Basin Plan,
WQ Order 90-5,
SIP, CTR,
Federal Regulations
Effluent Limitations
(concentration) / Five (5) Pollutants:
Copper, Mercury, Nickel, Tributyltin, and Zinc / Eight (8) Pollutants
Copper, Mercury, Nickel, 4-4’DDE, Dieldrin, Heptachlor Expoxide, Benzo(b)Fluoranthene, and Ideno(1,2,3-cd)Pyrene
Effluent Goals
(concentration) / Fourteen (14) Pollutants:
Aldrin, Chlordane, DDT, Dieldrin, Endrin, etc. / None
Effluent Limitations (Mass) / Thirteen (13) Pollutants:
Arsenic, Cadmium, Chromium, Lead, etc. / One (1) Pollutant
Mercury
Mercury mass limit / 2.66 kg/month / 0.231 kg/month + watershed-based study
Site –Specific Translators / None were used / Site-Specific translators were used for Chromium, Copper, Nickel, and Zinc
Bacteria Limitations / Total Coliform / Enterococcus

Appendix A: Cities of San Jose and Santa Clara, Water Pollution Control Plant

Tentative Order