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Home My WebLink AboutOC Pest County MeetingSAN DIEGO CREEK, UPPER AND LOWER NEWPORT BAY ORGANOCHLORINE TMDL Shelly Anghera, Ph.D. Susan Paulsen, Ph.D. PE June 7, 2018 1 OVERVIEW 2 Regulatory requirements for OC compounds have changed over time (SQOs for benthic organisms and human health) and TMDL targets are questionable (NWRI findings) Available data were re-evaluated to assess current conditions High detection limits complicate data analysis Concentrations in all media are generally declining Toxicity is largely gone, and, when present, not correlated with OCs In attainment with draft SQOs for human health and with SQOs for benthic life at many stations in Lower Newport Bay Additional data will be required to confirm current condition and better quantify rate of change RECOMMENDATIONS Continue implementation of watershed and Bay BMPs Proceed with planned sediment removal actions (will remove associated contaminants, improve sediment control in watershed) Enhanced erosion controls on agricultural lands where OCs may have been applied historically Continue watershed BMP implementation Others? Develop work plan for future monitoring Confirm resolution of analytical issues Bay: Optimize sample collection for SQOs (random stratified design for sediment, fish for HH SQO) Watershed: Continue watershed monitoring Build upon existing data collection efforts (e.g., Bight ‘18) Recommendations for regulatory process Extend TMDL compliance deadline to allow for additional data collection Bay: use SQOs (benthic organisms and HH) Watershed: Continue to monitor OCs in water, sediments, and fish of watershed for trends analyses Establish triggers for additional implementation actions if needed 3 EVALUATION OF AVAILABLE DATA Water column Freshwater Bay Sediments Freshwater Bay Chemistry Toxicity SQO for benthic organisms Biota Freshwater portions of watershed (fish, bird eggs) Bay (marine fish, SQO for HH, bird eggs) Trends in time 4 WATER QUALITY 5 WATER DATA SUMMARY FOR WATERSHED 6 Organo- chlorine Average concentration (2013-2017) below CTR Freshwater Aquatic Life criteria at all stations? Acute (CMC)Chronic (CCC) PCBs1 N/A Yes Chlordane1 Yes Yes 4,4’-DDT Yes No Toxaphene N/A N/A •Majority of samples below MDLs for all organochlorines •All toxaphene samples below MDLs, but many MDLs above CTR limits (2017 samples < CMC) •High number of non-detects generally prevented meaningful trend analysis 1 Informational TMDL targets BAY -WIDE WATER CONCENTRATIONS Average water concentrations for PCB, DDT, and chlordane were below acute and chronic criteria in Upper and Lower Newport Bay. Most samples were non-detect. Average PCB concentrations in water were slightly above the HH criterion TMDL target in both Upper and Lower Newport Bay PCB TMDL target HH criterion = 0.17 ng/L Upper Newport Bay = 0.35 ng/L Lower Newport Bay = 0.30 ng/L Average DDT concentrations in water were slightly above the HH and chronic criteria TMDL targets in Upper Newport Bay DDT TMDL target HH criterion = 0.59 ng/L DDT TMDL target chronic exposure = 1.0 ng/L Upper Newport Bay = 1.45 ng/L 7 SEDIMENT CHEMISTRY 8 SEDIMENT CHEMISTRY SUMMARY FOR WATERSHED 9 •Majority of samples below method detection limits (MDLs) •Only one DDT sample exceeded TMDL target of 6.98 ug/kg •PCBs and toxaphene concentrations below MDLs, but many MDLs above TMDL targets. •High number of non-detects generally prevented meaningful trend analysis Organo- chlorine Average concentration (2013-2017) below TMDL target at all stations? PCBs1 N/A Chlordane1 Yes Total DDT No Toxaphene N/A 1 Informational TMDL targets SEDIMENT CHEMISTRY SUMMARY FOR BAY 10 Based on last 5 years of data PCBs and chlordane below TMDL targets DDT TMDL target = 3.89 ppb (same as ERL) Upper Newport Bay average DDT = 8.1 ppb Lower Newport Bay average = DDT 12.9 ppb LNRHIRLNBRIN LNBTUB DDT IN BAY SEDIMENTS LNRHIR LNBRIN LNBTUB UNBSDC UNBJAM UNBNSB UNBCHB Filled circles = DDT detected Open circles = Non detect (1/2 detection limit) High number of non-detects generally prevented usability of data (2011-2015) SEDIMENT TOXICITY LNRHIR LNBRIN LNBTUB UNBSDC UNBJAM UNBNSB UNBCHB SUMMARY OF AVAILABLE TOXICITY DATA IN BAY •When present, toxicity occurs at low levels (60 to 80% survival) •No pattern related to OC concentrations (when toxicity occurred, OCs weren’t elevated) •No pattern in toxic events. However, out of 76 samples represented in the figure there was a higher frequency of occurrence of samples with less than 80% survival in the wet season (9) than dry (4) season 0% 20% 40% 60% 80% 100% 2013 2014 2015 2016 2017 Recent Annual Trends in Amphipod Toxicity Testing Results LNBHIR LNBTUB UNBCHB UNBJAM UNBNSB UNBSDC SEDIMENT QUALITY OBJECTIVES 14 BIGHT ‘13 SQO SCORES 15 B13-8269 B13-8292 B13-8291 B13-8290 B13-8275 B13-8279B13-8280 B13-8274 B13-8273 SEDIMENT QUALITY OBJECTIVES - SUMMARY OC Monitoring and Bight ‘13 Green = SQO score of likely unimpacted or unimpacted. Sediments are protective of benthic health. Upper Bay: 1 out of 6 samples (17%) meets SQOs Lower Bay: 6 out of 8 samples (75%) meet SQOs (excluding Rhine) 16 Data less than 5 years old BIOTA – FISH AND BIRDS 17 FISH DATA SUMMARY FOR WATERSHED 18 •Average PCBs concentrations below TMDL target at all but one station •Average total DDT concentrations below TMDL target at three of seven stations Organo- chlorine Average tissue concentration (2013-2017) below TMDL target at all stations? PCBs No Chlordane1 Yes Total DDT1 No Toxaphene Yes 1 Informational TMDL targets FISH DATA SUMMARY FOR BAY DDT and PCB are above human health and/or wildlife TMDL targets for fish tissue for certain species. Only 3 species and 17 individual fish tissue samples are available since 2011. SWRCB is adopting Part 2 SQO to evaluate human health impacts from OCs (fish and sediment data <5 yrs old) Chlordane meets Tier I screening DDT and PCB meet Tier II assessment 19 Waterbody Assessment Unit Analyte Final Outcome Category Upper Newport Bay Total DDT Unimpacted Total PCB Likely Unimpacted Lower Newport Bay Total DDT Unimpacted Total PCB Likely Unimpacted BIRD EGG DATA SUMMARY FOR WATERSHED 20 •No standards for bird egg data •Averages calculated using ½ MDL for all analytes •PCBs, chlordane, and DDTs detected in most bird egg samples •Toxaphene was not detected in the majority of samples •No trends over time were discernible Station Average bird egg concentration (2013-2017) (ng/g dry weight) PCBs Chlordane DDTs Toxaphene BCGC 1,580 150 1,660 44 IRWD 200 11 2,560 100 SDC 100 16 1,610 530 UCI 480 7.9 2,530 58 BIRD EGG DATA SUMMARY FOR BAY Sampling Dates 6/23/2013 5/21/2014 6/16/2017 ng / g d r y w i e g h t 0 2,000 4,000 6,000 8,000 10,000 12,000 14,000 16,000 18,000 20,000 Total PCB Aroclors in Forster's Tern Eggs UNB is the only site in Newport Bay Aroclor data are subjective Minimal data collected to assess trends Analytical methods have varied Note: MDL = 0 for calculating average PCB concentration for current condition 21 TREND ANALYSES 22 LNRHIRLNBRIN LNBTUB DDT IN SEDIMENT TREND ANALYSIS: UPPER NEWPORT BAY LNRHIR LNBRIN LNBTUB UNBSDC UNBJAM UNBNSB UNBCHB 0 10 20 30 40 50 60 70 80 90 100 20 0 5 20 0 6 20 0 7 20 0 8 20 0 9 20 1 0 20 1 1 20 1 2 20 1 3 20 1 4 20 1 5 20 1 6 20 1 7 20 1 8 20 1 9 20 2 0 20 2 1 20 2 2 20 2 3 20 2 4 20 2 5 Av e r a g e T o t a l D D T C o n c e n t r a t i o n ( p p b ) Monitoring Year UNBCHB UNBJAM UNBNSB UNBSDC UNBCHB R2=0.47 UNBJAM R2=0.22 UNBNSB R2=0.46 UNBSDC R2=0.23 Measured values for monitoring years 2011-2015 were non-detect. Removed for trend analysis •DDT is reducing in Upper Newport Bay •Given current trends, expect to meet TMDL targets in next 15 years, but additional data needed to confirm 0 10 20 30 40 50 60 70 80 20 0 5 20 0 6 20 0 7 20 0 8 20 0 9 20 1 0 20 1 1 20 1 2 20 1 3 20 1 4 20 1 5 20 1 6 20 1 7 20 1 8 20 1 9 20 2 0 20 2 1 20 2 2 Av e r a g e T o t a l D D T C o n c e n t r a t i o n ( p p b ) Monitoring Year LNBHIR LNBTUB LNBHIR R2=0.64 LNBTUB R2=0.74Measuredvalues for monitoring years 2011-2015 were non-detect. Removed for trend analysis LNRHIRLNBRIN LNBTUB DDT IN SEDIMENT TREND ANALYSIS:LOWER NEWPORT BAY LNRHIR LNBRIN LNBTUB UNBSDC UNBJAM UNBNSB UNBCHB •DDT is reducing in Lower Newport Bay •Given current trends, expect to meet TMDL targets in next 10 years, but additional data needed to confirm SEDIMENT TOXICITY TREND ANALYSIS:UPPER AND LOWER NEWPORT BAY Upper Newport Bay Lower Newport Bay Toxicity trends (2006 to 2017) show recovery OC MONITORING PROGRAM: SQO ASSESSMENT Trend indicates improvement over time Benthic community response driving Possibly Impacted assessment No to low toxicity observed LNBRIN (Rhine Channel) is consistently driven by benthic community structure and elevated chemistry, not toxicity UNBCHB UNBJAM UNBNSB UNBSDC LNBHIR LNBTUB LNBRIN 2009 Likely unimpacted Likely impacted Possibly impacted Clearly impacted Possibly impacted Possibly impacted NR 2010 Possibly impacted Possibly impacted Possibly impacted Likely impacted Possibly impacted Likely impacted NR 2011 Unimpacted Possibly impacted Likely unimpacted Possibly impacted Possibly impacted Likely impacted Likely impacted 2012 Unimpacted NR Possibly impacted Possibly impacted Possibly impacted Possibly impacted 2014 Unimpacted NR Unimpacted Possibly impacted Possibly impacted Possibly impacted Likely impacted 2016 Unimpacted Likely unimpacted Unimpacted Possibly impacted Likely unimpacted Possibly impacted NR Upper Newport Bay Waterbody Lower Newport Bay Waterbody FISH TISSUE TOXAPHENE TRENDS IN WATERSHED 27 •Three of five stations show downward trends over time. •Two of five stations show consistently low concentrations over time. = Toxaphene detected = Toxaphene not detected FISH TISSUE DDT TRENDS IN BAY Spotted sand bass collected in Lower Bay, except 2 (circled) locations in Upper Bay Spotted sand bass tissues suggest declining concentrations over time, and a significant relationship with sediment DDT, PCB, and chlordane concentrations 28 R² = 0.31520 5 10 15 20 25 30 35 40 45 50 2006 2008 2010 2012 2014 2016 2018 To t a l D D T ( w e t w t . ) p p b Sample Year Total DDT in Spotted Sand Bass FISH TISSUE DDT TRENDS IN BAY Top smelt collected in both Upper and Lower Bay Sample collection and handling may have varied over time Fish at Jamboree in 2014 show higher concentrations Trends over time are weak Lack of relationship between sediment and top smelt tissue 29 R² = 0.019 0 50 100 150 200 250 300 2006 2008 2010 2012 2014 2016 2018 To t a l D D T ( w e t w t . ) p p b Sample Year Total DDT in Top Smelt Jamboree REGIONAL TRENDS IN ORGANOCHLORINE PESTICIDES Total DDTs in Mussels Total chlordane in Mussels 30 Trend in Mussel Tissue Concentrations at the entrance to Newport Bay from NOAA program (SWAMP Mussel Watch Program; copied figures from site NBWJ; located at https://www.waterboards.ca.gov/water_issues/programs/swamp/mussel_watch.html) Natural Recovery: Reduction of Legacy Contaminants is Occurring Throughout Southern California and Newport Bay SUMMARY 31 32 NEWPORT BAY CURRENT CONDITION: TMDL COMPLIANCE SUMMARY Nu m e r i c T a r g e t s Human Health Sediment Quality Objectives DDTs PCBs Chlordane Fish Tissue for Human Health √ Tier II √ Tier II √ Tier I DDTs PCBs Chlordane Toxaphene Sediments NC √√√ Water CMC=√ CCC=NC(UNB) HH=NC CCC =√ HH=NC √na Fish tissue for human health criteria NC NC NC (UNB) √ (LNB)na Fish tissue for wildlife criteria NC √√na All Contaminants Benthos X NC Not yet demonstrated to be in compliance with RWQCB TMDL targets or SQO√ Compliant with TMDL target, below MDLs, or SQOCMC= acute criteriaCCC=chronic criteriaHH=human health criteria •Overall the sediment, water and tissue concentrations are lower than ever before. •The new HH SQOs are predicted to demonstrate sediments are protective of fish tissue for human consumption •Continued source reduction, BMPs, and natural recovery is predicted to bring bay into TMDL compliance •Remaining compliance issues: •DDT in water, sediment, and tissue – when compared to TMDL numeric target •Benthic SQOs score driven by moderately disturbed benthic community structure and low toxicity Benthic Sediment Quality Objectives 33 NEWPORT WATERSHED CURRENT CONDITION: TMDL COMPLIANCE SUMMARY Nu m e r i c T a r g e t s DDTs PCBs Chlordane Toxaphene Sediments NC √√√ Water CMC=√ CCC =NC HH=NC CCC =√ HH=NC CMC=√ CCC =√ HH=NC √1 Fish tissue for human health criteria NC Info TMDL Info TMDL √ Fish tissue for wildlife criteria √√ NC Not yet demonstrated to be in compliance with RWQCB TMDL target √Compliant with TMDL target or below MDLs1 Detection limit higher than criterionCMC= acute criteriaCCC=chronic criteriaHH=human health criteria •Overall the sediment, water and tissue concentrations are lower than ever before. •Continued source reduction, BMPs, and natural recovery are predicted to bring bay into TMDL compliance •Remaining compliance issues: •DDT in water, sediment, and tissue – when compared to numeric target •In general, fish tissues meet human health consumption risks, therefore, water column concentrations are likely protective SUMMARY 34 PROPOSED APPROACH FOR NEXT PHASE OF THE TMDL Conclusions from data review Provide scientific support for extension of TMDL timeline Significant and effective source reductions have been employed over last 15 years Contaminant trends in all media suggest current management actions have been effective, and attainment will be reached given sufficient time Design and conduct additional monitoring to confirm trends and demonstrate attainment of beneficial uses Next steps: Finalize OC report to summarize and evaluate the current condition Co-permittees to identify past and planned actions and BMPs in the watershed and Bay, including dredging history and plans, for inclusion in report – to include erosion controls and tackifiers for agricultural lands still in production where DDT may have been applied in the past Develop work plan for future monitoring with the goal to: To confirm trends over time (i.e., confirm continued effectiveness of natural recovery and management actions) To provide data and plan for additional management actions based on data triggers for future data collection To explain need for extended timeline for TMDL compliance 35 RECOMMENDED FURTHER DATA COLLECTION EFFORTS: Additional fish tissue samples should be collected to confirm the current condition of fish tissue in Newport Bay using new Part 2 SQOs Update monitoring program to include: Randomized sampling for SQO assessments Appropriate frequency and spatial extent of samples to characterize entire waterbody and to quantify trends Estimate background concentrations to set realistic expectations for further actions 36 ADDITIONAL MATERIALS 37 TMDL TARGETS 38 INFORMATIONAL TMDL TARGETS 39 Date Event May 1998 Newport Bay was included on the Section 303(d) list of impaired waters for metals, nutrients, pathogens, pesticides, priority organics, and sedimentation/siltation; San Diego Creek was included for metals, nutrients, pesticides, sedimentation/siltation, and unknown toxicity Jun 2002 USEPA adopted TMDLs for organochlorines in San Diego Creek and Newport Bay in response to a 303d listing for “unknown toxicity” Jul 2003 USEPA approved California’s 2002 303(d) List Sept 2004 SWRCB adopted State Listing Policy Sept 2007 RWQCB adopted RWQCB OC TMDL, which included targets for sediment, water, and fish; TMDL required development of detailed work plan to study conditions and targets in watershed Sept 2008 Sediment Quality Objectives (SQO) adopted by SWRCB; requires three lines of evidence for assessment, plus stressor identification Aug 2009 NWRI panel issues report finding RWQCB OC TMDL targets to be flawed, recommends ecological risk analysis to determine new targets Sept 2009 USEPA approves SQOs, SQO Policy becomes effective May 2009 OC MS4 permit adopted by RWQCB; includes WLAs from USEPA TMDL for urban runoff (DDT, chlordane, dieldrin, PCBs, toxaphene) Apr 2011 SWRCB modifies SQO Policy to include narrative objectives for resident finfish and wildlife Jul 2011 RWQCB modified OC TMDL to extend final compliance date to Dec 31, 2020 Oct 2012 SWRCB approved RWQCB OC TMDL Jul 2013 OAL approved RWQCB OC TMDL, triggering requirement to submit TRIP workplan within 3 months Oct 2013 TRIP workplan was submitted to RWQCB, as required by 2007 RWQCB OC TMDL; workplan describes extensive special studies but does not provide clear means of demonstrating compliance Nov 2013 USEPA approved RWQCB OC TMDL 40