Comments on Effluent Dominated Water Bodies CVRWQCB Draft Report September 2000

Transcription

1 Comments on Effluent Dominated Water Bodies CVRWQCB Draft Report September 2000 Submitted by G. Fred Lee, PhD, DEE G. Fred Lee & Associates El Macero, CA ph: (530) fx: (530) October 13, 2000 The Central Valley Regional Water Quality Control Board (CVRWQCB) is in the process of developing a Regional Board policy governing water quality management in wastewater effluent dominated waterbodies. NPDES dischargers to such waterbodies find that they may have to treat the effluent to a greater degree to meet water quality objectives in the receiving waters than similar discharges discharging to larger receiving waters. While some of those who work in California who face this problem claim that this is a problem restricted to the arid west, in fact, this is a national problem that is related to municipalities and other wastewater dischargers attempting to develop urbanized areas where the wastewaters produced by such areas are to be discharged to nearby low flow streams. Since many of these streams are important aquatic resources for the region, conventionally treated domestic wastewaters can have sufficient pollutants in the treated wastewaters to be adverse to the aquatic life beneficial uses of the receiving waters. This is especially true in the Central Valley where many small streams which have seasonal flow are critical habitat for steelhead trout and Chinook salmon as well as other desirable forms of aquatic and terrestrial life. An issue of particular concern in the Central Valley that needs to be addressed is whether entities such as a municipality or a university can expect to continue to develop/expand its wastewater discharges and stormwater runoff to low flow streams and still only provide the level of treatment of the wastewater discharges that is being provided for similar discharges to larger waterbodies. Under the current regulatory requirements at the federal and state level, NPDES permittees should recognize that if they wish to maintain and especially expand their wastewater discharges to low flow streams, they must provide far greater levels of treatment than conventional treatments in order to protect the beneficial uses of the low flow receiving waters. The assimilative capacity of the receiving waters for wastewater discharges must be considered in developing expanding populations serving NPDES permitted facilities. An example of this type of problem occurs with the expansion of the University of California, Davis (UCD). The current UCD administration periodically announces plans for expansion. At the same time, this administration objects to having to treat the campus wastewaters to fully protect the beneficial uses of the receiving waters for the wastewater discharges. These expansion plans fail to reliably address the need for the university to treat the campus wastewaters to ever-increasing degrees prior to discharge to Putah Creek. Putah Creek, at times, can have low flow and thereby provide limited dilution for the residual pollutants in the UCD treated wastewaters. Continued expansion of UCD will require that the university provide extraordinary treatment of its wastewaters before

2 discharge into Putah Creek in order to protect the beneficial uses of this waterbody. The UCD situation is not atypical of many communities in the Central Valley. Presented below are my comments on the CVRWQCB draft report devoted to effluent dominated waterbodies. Staff Recommended Approach The CVRWQCB has recommended Option 3 for developing a CVRWQCB policy governing NPDES permitted discharges to effluent dominated waterbodies. Basically, this option focuses on working with stakeholders in the Placer County area in addressing the concerns of the stakeholders in meeting water quality objectives in the receiving waters for the wastewater discharges. It is suggested that the results of the Option 3 efforts will have some transferability to other watersheds. The recommended approach appears to be required by the fact that the current Regional Board budgeting process does not provide the Board with the necessary funds to carry out the federal and state regulatory requirements in an appropriate and timely manner. There is need for the stakeholders throughout the state who are concerned about the appropriate regulation of wastewater discharges to effluent dominated waterbodies to work with their legislators to obtain the necessary funding for the CVRWQCB and other Regional Boards to reliably implement regulatory requirements in a timely manner. From the discussions at the CVRWQCB Effluent Dominated Waterbody workshop, it appears that several of the current CVRWQCB Basin Plan objectives such as ph, suspended solids, and temperature are more restrictive than necessary to protect the beneficial uses of waterbodies. I support critically reviewing all existing Basin Plan objectives to ensure that they are adequately protective without being unnecessarily overprotective. Additional discussion of issues that need to be addressed in revising the Basin Plan are presented in the subsequent section of these comments. Overall I find that the CVRWQCB staff s Effluent Dominated Water Bodies report presents an appropriate discussion of many of the issues that need to be considered in developing a CVRWQCB policy governing NPDES permitted discharges to low flow streams. Specific comments on issues and the report are presented below. Specific Comments Page 8, first paragraph, first line,...adopt water quality criteria should be changed to adopt water quality standards. There is an inconsistent approach used in how US is presented in some locations without periods and in others, with periods. It should be consistent. This problem occurs in the first full paragraph on page 13 and in the last paragraph of page 12. 2

3 Page 17, first paragraph mentions land disposal of wastewaters. It is being found that the CVRWQCB, in permitting land disposal of domestic wastewaters, is not adequately evaluating the potential for groundwater and surface water pollution by this practice. All land disposal of wastewaters should be required to reliably monitor groundwaters underlying and downgradient of the wastewater disposal area to ensure that groundwater pollution by TDS, nitrate, and other constituents is not occurring. Further, those who practice land disposal of wastewater should be required as part of the permitting process to define the fate of the constituents present in the wastewaters with particular reference to shallow ground water discharge to surface waters as a mode of transport of wastewater constituents to surface waters. All wastewater dischargers to land should be required to develop comprehensive stormwater runoff monitoring programs to assess whether constituents present in the wastewater that accumulate in the disposal area surface soils are transported to surface waters during stormwater runoff events. Page 18, under Current Status states, Dischargers often have difficulty meeting these water quality objectives in undiluted effluent. In addition, the objectives for turbidity, temperature, and ph are often violated because they are based on allowing only limited changes from background conditions. I agree that the current Basin Plan objectives for these current parameters are likely overprotective in some situations. It appears that at the time that these objectives were adopted in the Basin Plan, inadequate attention was given to diel changes in ph and temperature. Often in small streams, natural diel changes can be several degrees C, and the ph can change by more than one unit. It is important to understand that both steelhead trout and Chinook salmon likely, oversummer in the stream in which they have developed. Relaxation of regulatory water quality objectives during the summer should only be allowed where it has been adequately demonstrated that the cold water fishes that are present in the stream are adequately protected. Another issue that needs to be addressed in clarification of the interpretation of the Basin Plan objectives is whether the absolute maximum ph or minimum DO that occurs at any time in the day/night and at any location in the waterbody including the sediment water interface is the value that is used to evaluate violations of the Basin Plan objectives. The worst-case-based implementation of the DO objectives downstream of the domestic wastewater discharge will cause significantly different allowable discharge loads of constituents than using the average DO. In order to keep the DO from having any excursions below the water quality objective, it could become necessary to treat the wastewater for nitrogen and phosphorus removal in order to reduce the magnitude of the photosynthetic-caused diel DO changes. Page 19, second paragraph states that dischargers have expressed concern regarding the derivation of the ammonia and nitrogen limitations. No information is provided as to what the nature of this concern is and what is meant by nitrogen limitation. The US EPA has updated the ammonia water quality criteria in December These criteria have not changed significantly from previous versions. Ammonia in domestic wastewater discharges to low flow streams, especially during the fall, could readily become a constituent that causes a water quality objective violation when the 3

4 objective is determined by the narrative standard of no discharge of toxics in toxic amounts. So long as the State Water Resources Control Board and the CVRWQCB do not adopt water quality objectives for ammonia, the US EPA, December 1999 ammonia criteria will become de facto objectives through the narrative toxicity objective. Since both temperature and ph are important in influencing ammonia toxicity, the CVRWQCB needs to address the worst case vs. averaging issues raised with ph and temperature for ammonia toxicity as well, since toxic conditions can exist in late afternoon, but not exist in early morning. Page 19, under Toxic Chemicals, based on my experience, effluent dominated streams typically have sufficient organics derived from the effluent to complex/detoxify many heavy metals. A discharger that faces limitations on its effluent loadings based on excessive heavy metals compared to the CTR criteria should consider conducting a site-specific evaluation of water quality criteria/objectives. This could provide considerable relief from the worst-case-based CTR criteria and still be protective of aquatic life.. Page 19, under Turbidity, states in the third sentence that the turbidity test is a surrogate for determining the relative levels of suspended and settable [sic] solids in the water column. The turbidity test as practiced is a measure of light scattering in the water column. It is not a reliable measure of settleable solids in the water column. This paragraph needs to be rewritten. Page 19, last paragraph, from the information provided, it appears from having worked on the impacts of turbidity on aquatic life, that the current Basin Plan turbidity objective is too restrictive. Considerable changes in the light scattering properties (turbidity) of a water can occur without significantly adversely impacting the aquatic life-related beneficial uses of a waterbody. Page 20, first paragraph, first sentence, first two lines, the statement that turbidity can be used as an indicator of effectiveness of treatment processes for pathogen removal in WWTPs is not reliable and should be deleted. This approach is reliable only for certain types of pathogens. It is not reliable for all pathogens. Page 20, first paragraph, last sentence, provides reference to a DHS proposed regulation for water recycling. No date is provided with the reference. It should be. Also, if this is an older reference, I understand the DHS has new wastewater recycling regulations available. These were discussed by Bob Hultquist at the recent CA/NV AWWA meeting that was held in Sacramento. Page 22, under Dissolved Oxygen, second paragraph needs to address the issues discussed above of absolute minimum DO at any time and location vs. an average DO. Page 23, third paragraph, I agree with changing the Basin Plan limiting the ph change to no more than 0.5 ph units. This is overly restrictive. Page 23 under Bacteria, I do not understand why the word Americans is used. This risk of illness is not to just Americans. Also at mid-paragraph, 4

5 Indicator organisms are used to assess the sanitary quality of water, because human pathogens in surface waters are too numerous and too difficult to assess on a routine basis. While this statement is often made, it should not be perpetuated by the Regional Board. It is statements like this which have hindered the development of monitoring methods for pathogens. It had been known since the 1940s that the coliform pathogen-indicator organism standard is not protective for several other types of pathogens. Over a thousand people a year die in the US from drinking waters containing pathogens that meet the coliform drinking water standards. The US EPA is finally beginning to develop effective methods for monitoring pathogens because of the unreliability of the coliform standards. The statement in the last sentence of the first paragraph, page 23, under Bacteria, The more resistant total coliform organisms are better indicators of the pathogenic quality of water is not accurate. As discussed at the US EPA West Coast Regional Beach Conference, August 1999, the State of California has made a significant error in adopting the total coliform standard for contact recreation. The CVRWQCB should not perpetuate this error by making such statements. Bottom of page 24, top of page 25, discusses disinfection of wastewaters where the statement is made, Adequate disinfection is defined as wastewater which has a median number of coliform organisms that does not exceed 2.2 per 100 ml. and the number of coliform organisms does not exceed 23 per 100 ml. in more than one sample within any 30-day period. This approach is well known not to be protective from both viral and protozoan cyst human pathogens. Failures in the coagulation infiltration of the wastewater can result in failure to remove viruses and parasites and still meet the coliform standards. If the CVRWQCB is to include a discussion of this out-of-date approach for judging the adequacy of disinfection, then a discussion of its deficiency should also be included. Page 25, under Efforts to Address EDWs, tries to portray the image that the EDW problem is unique to the arid and semi-arid west. As discussed above, this is not true. This is a national problem that occurs throughout the country. Page 30, under Evaluation: mention is made about data collection as part of the evaluation process. It is extremely important that a key component of the data collection is properly conducted aquatic organism assemblage information relative to habitat characteristics. It is only through such studies that it will be possible to develop appropriate degrees of treatment for NPDES permitted domestic wastewater sources that will protect the beneficial uses of effluent dominated waterbodies as well as non-effluent dominated waterbodies in a technically valid cost-effective manner. It is the author s experience, based on an in-depth review of University of California, Davis permitted wastewater discharges to Putah Creek, that the CVRWQCB is not requiring adequate evaluation of the potential impacts of these discharges on the beneficial uses of Putah Creek. Putah Creek is an important recreational resource and sports fishery in Yolo and Solano Counties. It has 5

6 been found to support reproduction of Chinook salmon. It is an effluent dominated waterbody where the UCD campus wastewater effluent discharges, at times, is the primary source of water for the lower reaches of the Creek. While recently this situation has been alleviated to some extent with a court order requiring that upstream agricultural interests must maintain a certain minimum flow in the Creek, there still will be times, especially under drought conditions and with the proposed expansions of UCD s campus, where the campus wastewaters will be the dominant source of water for the lower Creek. The CVRWQCB, as part of permitting the UCD campus wastewater discharges to the Creek, refused to support the public s request that UCD conduct the necessary monitoring programs to determine if constituents discharged in the wastewaters are leading to excessive bioaccumulation of hazardous chemicals in Putah Creek fish. It was found as part of US EPA Region 9 and ATSDR studies that under low flow conditions, UCD s discharge of its wastewaters to Putah Creek was contributing to excessive mercury bioaccumulation in fish taken from the Creek in the vicinity of the discharge (Lee, 1998). Some of the mercury found in Putah Creek fish was radioactive mercury which almost certainly was derived from UCD s laboratory activities. Further, the level of treatment being provided by UCD during the low flow conditions was such that sludge deposits were developed near UCD s campus wastewater discharge. These deposits could readily have been a significant factor in contributing to the methylation of mercury from UCD and other sources, which contributed to the high levels of mercury found in Putah Creek fish near the point of campus wastewater discharge. The UCD campus wastewater discharge is not unique. The CVRWQCB has adopted a policy that it will be precedent setting to require the NPDES dischargers to conduct the necessary monitoring program to reliably evaluate whether constituents in the wastewaters cause water quality use impairments through bioaccumulation or aquatic life toxicity. There can readily be situations, especially in effluent dominated waterbodies, where a nontoxic wastewater discharge will become toxic downstream of the discharge. Lee (1996, 1997) has discussed the problems with CVRWQCB s permitting UCD s campus wastewater discharges of chromium to Putah Creek. The concentrations of chromium in the campus wastewater discharges have been found to be toxic to zooplankton if the chromium is in the form of chromium VI. The conditions that exist in Putah Creek are such that chromium III in the campus wastewater effluent could be converted to chromium VI downstream of the discharge (Lee and Jones-Lee, 1997, 1998a,b). The CVRWQCB refused, as part of renewal of an NPDES permit, to require that UCD adequately monitor Putah Creek to be certain that the high levels of chromium III in the wastewater effluent were not converted to chromium VI downstream of the discharge. As part of developing a protective policy for NPDES discharges to effluent dominated waterbodies, the CVRWQCB should not only relax overly stringent Basin Plan objectives, but also require that NPDES dischargers conduct comprehensive monitoring programs of the receiving waters including downstream toxicity and bioaccumulation to determine whether the constituents in the wastewater discharge, especially under low receiving water flow conditions, are contributing to beneficial use impairment of these waters. The approach of resisting proper wastewater impact evaluation based on it being precedent setting should be terminated. 6

7 References Lee, G. F., Supplement/Addendum to Petition of Order No Issued by the Central Valley Regional Water Quality Control Board on August 9, 1996 to the University of California at Davis for the UCD Campus Landfill Ground Water Cleanup System to Address the New Information Provided by the University of California at Davis and the CVRWQCB Staff at the CVRWQCB September 20, 1996 Hearing Devoted to Chromium Technical Issues, G. Fred Lee & Associates, El Macero, CA, 19pp, October 17 (1996). Lee, G. F., Comments on Tentative Waste Discharge Requirements and Cease and Desist Order NPDES No. CA for University of California, Davis Campus Wastewater Treatment Plant Yolo and Solano Counties Dated August 27, 1997, Report of G. Fred Lee & Associates, El Macero, CA, October (1997). Lee, G. F., Excessive Mercury Bioaccumulation in Putah Creek Fish, Report of G. Fred Lee & Associates, El Macero, CA (1998). Lee, G. F. and Jones-Lee, A. Chromium Speciation: Key to Reliable Control of Chromium Toxicity to Aquatic Life, Presented at the American Chemical Society National Meeting poster session, San Francisco, CA, April (1997). Lee, G. F. and Jones-Lee, A., Under-Regulation of Chromium in Ambient Waters, Learned Discourses: Timely Scientific Opinions, SETAC News 18(4):22 July (1998a). Lee, G. F. and Jones-Lee, A., Under-Regulation of Chromium in Ambient Waters - Expanded Discussion, Report, G. Fred Lee & Associates, February (1998b). 7