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HomeMy WebLinkAbout07.a.1) (Handout)7 Board Meeting of July 19, 2012 H a ndo�.�f Additional Written Announcement: Sacramento Regional NPDES Permit g) General Manager Ann Farrell Testifies at Workshop on Sacramento Regional Wastewater Treatment Plant Waste Discharge Requirements On July 18, 2012, General Manager Ann Farrell testified at the workshop regarding the State Water Resources Control Board's review by its own motion of the Waste Discharge Requirements Order No. R5- 2010 -0114 for the Sacramento Regional Wastewater Treatment Plant. This was a somewhat unusual step in that the State Board does not typically review permits on its own motion. State Board staff issued a draft order in advance of the workshop partially vacating the original Order by relaxing the nitrate requirement. The permit was originally issued by the Central Valley Regional Water Quality Control Board and there has been quite a bit of controversy regarding the very aggressive new requirements contained in the permit, thus the State Board felt it important to provide a venue to hear comments from the public on the permit. This controversy was reflected by the comments at the workshop. Those associated with the water supply and fisheries communities were firmly in favor of the permit requirements and took issue with the relaxation of the nitrate requirement. They also suggested that even more strict requirements should be considered in some areas, such as temperature and metals. Those associated with the wastewater discharger community, such as BACWA, CASA and ourselves, suggested that some of the requirements were overreaching given the state of the science regarding Delta water quality. All five members of the Board were present and listened attentively. They are expected to take several months to review the material and make any decisions with respect to changes to the order. Ms. Farrell's testimony is attached. Ann Farrell, General Manager, Central Contra Costa Sanitary District, Martinez, CA SWRCB Workshop Testimony July 18, 2012 Sacramento Regional Wastewater Treatment Plant Waste Discharge Requirements Central San serves approximately 450,000 persons and discharges about 40 mgd to Suisun Bay near the Carquinez Strait. Introduction: We and our rate payers have a vested interest in the outcome of these proceedings because we too contribute to the ammonia and nutrient loads in the system. As stewards of our rate payers dollars, we simply want to do the right thing. To us, this means having sound science to justify installing advanced treatment that will cost us on the order of $100 -$200 million, depending on the level of treatment required, as well as adding substantially to our energy consumption, green house gas generation, and operation and maintenance costs. For these reasons, we are currently participating in the San Francisco Bay NNE process as well as providing funding for a number of collaborative studies to attempt to advance the understanding of nutrient impacts to the Bay Delta System. We have three brief comments on the state of the science. 1) Further experimental data is needed to conclusively define the ammonia toxicity threshold for P. Forbesi. CCCSD statistical analysis using accepted data analysis procedures calculates much higher toxicity thresholds. ....for example a threshold of 3.23 mg /I for 31 day reproduction in adults as compared to the .36 mg /I threshold contained in correspondence from U C Davis to the Central Valley Regional Board and cited in the draft Order. This calculation difference occurs because the researcher averaged the replicates for each ammonia concentration instead of entering the individual values in the statistical calculation. Due to the high variability of the results, when individual values are analyzed instead of averages, the toxicity threshold is an order of magnitude higher. The occurrence of levels of ammonia exceeding .36 mg /I up to 30 miles downstream was one of the key reasons for denying the mixing zone for ammonia. If the toxicity threshold is actually an order of magnitude higher, then this conclusion comes into question. We believe additional statistical analysis and studies on ammonia toxicity to P. Forbesi are needed and are working to refine the study plan and fund additional work in this area. 2) Recent phytoplankton trends show increases in phytoplankton. Dr. Alan Jassby of UC Davis reported in the San Francisco Estuary and Watershed Science in February 2008 that median phytoplankton biomass in the Delta increased by about 30% from the early 1990's to the early 2000's. This occurred during a time when ammonia discharges were increasing substantially due to increases in population. The Spring 2011 IEP Newsletter notes that phytoplankton numbers in 2010 were much higher overall when compared to the previous 2 years.....this occurred without any reduction in ammonia discharges. Studies underway in the San Francisco Bay region on the toxicity of ammonia to phytoplankton, which have been partially funded by CCCSD, have been inconclusive to date. 3) Grazing of phytoplankton in Bay Delta by clams should be examined as a likely cause of phytoplankton reduction. Phytoplankton increase in the South Bay has been correlated with clam population decline by Jim Cloern of USGS. Clam population increases in the other parts of the Bay may correlate better with phytoplankton decreases than ammonia increases. This correlation needs to be developed and studied in parallel with ongoing studies regarding ammonia toxicity to phytoplankton. Conclusion: Our review of the evidence suggests that more work is needed before we can say conclusively that removing ammonia from the Delta will result in measureable improvements in phytoplankton and copepod production and resulting improvements in the productivity of pelagic organisms. There are many stressors in the Bay Delta system and ammonia may play a role, but is it a controlling factor? Similar efforts in the Chesapeake Bay and the Narragansett Bay have not shown that millions of dollars spent on advanced treatment of wastewater discharges to remove nutrients to ever lower levels result in measureable improvements in water quality. We do not want to find ourselves in the same situation in ten years from now having spent millions to achieve little. Therefore we urge you to review all of the scientific data and be convinced that it is adequate to support the expenditures of resources that will result if you uphold the proposed order. Our rate payers as well as all who benefit from a healthy Bay Delta system are depending on you.