New Emphasis on Sediment Quality Objectives Water Board, SCCWRP, SFEI RMP Annual Meeting 2007 Water Board Policy Development 1989 Legislature amended Water Code Sec Sediment Quality Objectives reasonable protection of beneficial uses November Water Board hearing Chemistry - Biology Toxicity Process driven by Scientific Steering Comm Conceptual Framework Direct Effects Severity of Effect Potential for Chemically Mediated Effect Station Assessment BenthosToxicityChemistryToxicity Three lines of evidence (LOE) needed to assess direct effects of sediment contamination Toxicity Line of Evidence Benthic Community LOE - Steps Compile Data Standardize taxonomy Calculate abundance and other metrics Calculate Benthic Indices Benthic Response Index (BRI) Index of Biotic Integrity (IBI) Relative Benthic Index (RBI) River Invertebrate Prediction and Classification System (RIVPACS) Combine Index Scores Benthic Community LOE - Steps Compile Data Standardize taxonomy Calculate abundance and other metrics Calculate Benthic Indices Benthic Response Index (BRI) Index of Biotic Integrity (IBI) Relative Benthic Index (RBI) River Invertebrate Prediction and Classification System (RIVPACS) Combine Index Scores Chemistry Line of Evidence Sediment Quality Lines of Evidence RESPONSE CHEMISTRY (Exposure) TOXICITY (Toxicity) BENTHOS (Disturbance) Equivalent to reference or control condition (1) Minimal Exposure NontoxicReference Slight change of uncertain statistical significance (2) Low Exposure Low Toxicity Low Disturbance Reliable difference generally regarded as significant (3) Moderate Exposure Moderate Toxicity Moderate Disturbance Highly reliable response of high magnitude (4) High Exposure High Toxicity High Disturbance Direct Effects Station Assessment Unimpacted Likely Unimpacted Possibly Impacted Likely Impacted Clearly Impacted Inconclusive Six assessment categories 64 LOE Combinations 6 Assessment Categories MLOE Integration Framework MLOE Conceptual Framework Direct Effects Severity of Effect Potential for Chemically Mediated Effect Station Assessment BenthosToxicityChemistryToxicity Severity of Effect NontoxicLow ToxicityModerate Toxicity High Toxicity ReferenceUnaffected Low Effect Low Disturbance UnaffectedLow Effect Moderate Disturbance Moderate Effect High Disturbance Moderate Effect High Effect Benthos Toxicity Potential Effects are Chemically Mediated NontoxicLow ToxicityModerate Toxicity High Toxicity Minimal Exposure Minimal Potential Low Potential Moderate Potential Low Exposure Minimal Potential Low Potential Moderate Potential Moderate Exposure Low Potential Moderate Potential High Exposure Moderate Potential High Potential Chemistry Toxicity MLOE Conceptual Framework Direct Effects Severity of Effect Potential for Chemically Mediated Effect Station Assessment BenthosToxicityChemistryToxicity Station Categories Unimpacted - no significant adverse impacts. Likely Unimpacted - some uncertainty from small disagreement among the LOE. Possibly Impacted - Small impacts or LOE disagreement cause substantial uncertainty. Likely Impacted - Evidence persuasive, some disagreement among LOE. Clearly Impacted - clear and severe adverse impacts Inconclusive - Large disagreement among the LOE Station Assessment UnaffectedLow EffectModerate Effect High Effect Minimal Potential Unimpacted Likely Unimpacted or Inconclusive Low Potential Unimpacted Likely Unimpacted Possibly Impacted Moderate Potential Likely Unimpacted Possibly Impacted or Inconclusive Likely Impacted High Potential Likely Unimpacted or Inconclusive Likely Impacted Clearly Impacted Potential that Effects are Chemically Mediated Severity of Effect Sec 305 (b) Report Test Common Approach in Regions RegionToxicityBenthosChemistry NorthEohaustoriusRBI CA LRM CSI SFBEohaustorius RBI, IBI, RIVPACS, BRI CA LRM CSI SouthEohaustorius RBI, IBI, RIVPACS, BRI CA LRM CSI Common Tools: Eohaustorius, RBI, CA LRM & CSI Results LOE Responses (% Area) RegionResponseBenthosToxicityChemistry NorthAffected27171 SFBAffected SouthAffected Affected: Moderate or High response Chemistry:Toxicity Relationships Effect of Tool Differences on % Area Estimates RegionResponseToolsBenthosMLOE NorthAffectedAll2718 NorthAffectedCommon2718 SFBAffectedAll3896 SFBAffectedCommon85100 SouthAffectedAll2338 SouthAffectedCommon3640 Affected Benthos: Moderate or High response Affected MLOE: Possibly, Likely, or Clearly Impacted RMP Response Implement Sediment Triad Regional Consensus on Indices Assessment of Toxicity Causes Sediment Chemistry Classification Steps Compile Data Calculate sums, estimate nondetects Calculate Chemistry Indicators (SQGs) Chem-Tox: CA LRM (maximum probability of toxicity) Chem-Benthos: CSI (weighted mean score) Combine Indicator Scores to Determine Chemistry LOE Category Toxicity Classification Steps Compile Data Normalize to control response Statistical significance tests Apply Toxicity Classification Criteria Amphipod survival (Eohaustorius estuarius) Determine Toxicity LOE Category Statewide Condition California Regions North 139 km 2 11% n = 27 SFB 1020 km 2 79% n = 40 South 135 km 2, 10% n = 314 Total = 1295 km 2 North 139 km 2 San Francisco Bay 1020 km 2 Unimpacted Likely Unimpacted Possibly Impacted Likely Impacted Clearly Impacted Inconclusive South 135 km 2 Regional Condition