C OPPER AND N ICKEL TMDL D EVELOPMENT: L OWER S OUTH B AY

CCOPPER AND OPPER AND NNICKEL ICKEL TMDLTMDL DDEVELOPMENT:EVELOPMENT:

LLOWER OWER SSOUTH OUTH BBAYAY

CCOPPER AND OPPER AND NNICKEL ICKEL TMDLTMDL DDEVELOPMENT:EVELOPMENT:

LLOWER OWER SSOUTH OUTH BBAYAY

2

Presentation OverviewPresentation OverviewPresentation OverviewPresentation Overview

Scientifically Defensible Site Specific Objectives

Key Elements of the TMDL Process

Lessons Learned and Recommendations

3

Proposed SSOs for Copper and Nickel Proposed SSOs for Copper and Nickel for San Francisco Bay South of the for San Francisco Bay South of the Dumbarton BridgeDumbarton Bridge

Proposed SSOs for Copper and Nickel Proposed SSOs for Copper and Nickel for San Francisco Bay South of the for San Francisco Bay South of the Dumbarton BridgeDumbarton Bridge

Chronic6.9 g/l dissolved copper12 g/l dissolved nickel

Acute10.8 g/l dissolved copper62.4 g/l dissolved nickel

4

Key Elements of the TMDL ProcessKey Elements of the TMDL ProcessKey Elements of the TMDL ProcessKey Elements of the TMDL Process

Stakeholder Involvement and City of San Jose Funding and Commitment

Source Characterization

Conceptual Model Development

Impairment Assessment

Copper and Nickel Action Plans

Task 1Task 1Conceptual Model Conceptual Model Report for Copper Report for Copper and Nickel in and Nickel in Lower South San Lower South San Francisco BayFrancisco Bay

Task 1Task 1Conceptual Model Conceptual Model Report for Copper Report for Copper and Nickel in and Nickel in Lower South San Lower South San Francisco BayFrancisco Bay

6

Role of the Conceptual Model in Role of the Conceptual Model in the TMDL Projectthe TMDL ProjectRole of the Conceptual Model in Role of the Conceptual Model in the TMDL Projectthe TMDL Project

Summarize current understanding of Cu and Ni in Lower South San Francisco Bay

Communicate information to wide audience

Provide technical basis for project planning

Conceptual Model for Copper Conceptual Model for Copper Concentrations in the South BayConcentrations in the South BayConceptual Model for Copper Conceptual Model for Copper Concentrations in the South BayConcentrations in the South Bay

Average Average Total and Total and Dissolved Dissolved Copper Copper ConcentratioConcentration n (1993-1997 (1993-1997 Data)Data)

Average Average Total and Total and Dissolved Dissolved Copper Copper ConcentratioConcentration n (1993-1997 (1993-1997 Data)Data)

Copper Inventories and Loadings Copper Inventories and Loadings in in Lower South San Francisco BayLower South San Francisco Bay

Copper Inventories and Loadings Copper Inventories and Loadings in in Lower South San Francisco BayLower South San Francisco Bay

Copper Concentrations in Copper Concentrations in Lower South San Francisco BayLower South San Francisco BayCopper Concentrations in Copper Concentrations in Lower South San Francisco BayLower South San Francisco Bay

Copper Mass Balance ModelCopper Mass Balance ModelCopper Mass Balance ModelCopper Mass Balance Model

Simplified but realistic: Hydrodynamics generated from 3D model

Calculates Internal Loadings

Calculates Loading – Concentration Response

12

How Would Bay Respond to a 250 How Would Bay Respond to a 250 kg Loading Change During Wet kg Loading Change During Wet Season?Season?

How Would Bay Respond to a 250 How Would Bay Respond to a 250 kg Loading Change During Wet kg Loading Change During Wet Season?Season? 250 kg would be a Significant

Change

Dissolved Concentrations:See bar chart

Conclude:Lower South Bay is Buffered for Cu

13

Uncertainties and Uncertainties and Recommendations Recommendations for Additional Studiesfor Additional Studies

Uncertainties and Uncertainties and Recommendations Recommendations for Additional Studiesfor Additional Studies Limited Understanding of Processes in South

Bay• Sedimentation/Resuspension Dynamics• Adsorption/Desorption Kinetics• Biogeochemical processes influencing metal speciation• Effects of speciation and competing metals on

phytoplankton uptake and toxicity• Biological cycling in sediments and water column

Direct Data Limitation• Limited Sediment Core Data• Nonpoint source tributary loads • Food web transfer• Resuspension fluxes and other sediment-water

interactions

Task 2Task 2Impairment Impairment Assessment Report Assessment Report for Copper and for Copper and Nickel in Lower Nickel in Lower South San South San Francisco BayFrancisco Bay

Task 2Task 2Impairment Impairment Assessment Report Assessment Report for Copper and for Copper and Nickel in Lower Nickel in Lower South San South San Francisco BayFrancisco Bay

15

Task 2: Impairment AssessmentTask 2: Impairment AssessmentTask 2: Impairment AssessmentTask 2: Impairment Assessment

Compile and evaluate data on ambient concentrations and toxicity information

Identify, evaluate and select indicators of beneficial-use impairment

Develop endpoints for the selected indicators

Assess levels of uncertainty

Recommend numeric values for site-specific objectives

Purpose: To present new information and to re-evaluate the determination that the beneficial uses of the South Bay are impaired due to ambient concentrations of copper and nickel.

Goals:

Strategy to Assess Impairment of Strategy to Assess Impairment of Beneficial UsesBeneficial UsesStrategy to Assess Impairment of Strategy to Assess Impairment of Beneficial UsesBeneficial Uses

17

Proposed IndicatorsProposed IndicatorsProposed IndicatorsProposed Indicators

Individual Species Toxicity Tests

Aquatic Ecological Risk Assessment Protocol (AERAP)

Site-Specific Studies

Phytoplankton

Benthic Macroinvertebrates

Ratio of Simultaneously Extracted Metals to Acid Volatile Sulfides (SEM/AVS)

Charismatic Macrofuna: Harbor Seals and Birds

18

Phytoplankton ToxicityPhytoplankton ToxicityPhytoplankton ToxicityPhytoplankton Toxicity

Phytoplankton in laboratory experiments are sensitive to concentrations of free ionic Cu that have been measured in the South Bay

Several site-specific water quality variables that must be taken into account to predict the toxicity of free ionic copper

Insufficient data to predict the effects of free ionic Cu in the South Bay

Several unanswered questions regarding the applicability of the test results to developing water quality objectives

Conceptual Model for Copper Conceptual Model for Copper Concentrations in the South BayConcentrations in the South BayConceptual Model for Copper Conceptual Model for Copper Concentrations in the South BayConcentrations in the South Bay

Copper Copper Uptake and Uptake and Toxicity in Toxicity in PhytoplanktoPhytoplanktonn

Copper Copper Uptake and Uptake and Toxicity in Toxicity in PhytoplanktoPhytoplanktonn

Range of pMRange of pM++ Values in Oceanic Values in Oceanic and Estuarine Environmentand Estuarine EnvironmentRange of pMRange of pM++ Values in Oceanic Values in Oceanic and Estuarine Environmentand Estuarine Environment

Spatial and Temporal Variability in Spatial and Temporal Variability in Picocyanobacteria in San Picocyanobacteria in San Francisco BayFrancisco Bay

Spatial and Temporal Variability in Spatial and Temporal Variability in Picocyanobacteria in San Picocyanobacteria in San Francisco BayFrancisco Bay

24

Lessons LearnedLessons LearnedLessons LearnedLessons Learned

Substantial amount of data and information required to implement science-based approach

Additional technical information required to support regulatory decision making process

Comprehensive monitoring programs do not meet all the information requirements of the regulatory decision-making process