Setting Standards: The Science of Setting Standards: The Science of Water Quality CriteriaWater Quality Criteria

EA Engineering, Science, EA Engineering, Science, and Technologyand Technology

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PresentedPresented byby: : James B. WhitakerJames B. Whitaker

Review of Annex 1 of the GLWQAReview of Annex 1 of the GLWQA

IJC Great Lakes Science Advisory BoardIJC Great Lakes Science Advisory Board

21 March 200121 March 2001

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IntroductionIntroduction

Setting standardsSetting standards

Standards are a necessityStandards are a necessity

The ideal vs. the realityThe ideal vs. the reality

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IntroductionIntroduction

Confusion introduced by terminologyConfusion introduced by terminology

Water Quality StandardsWater Quality Standards

Water Quality CriteriaWater Quality Criteria

Specific ObjectivesSpecific Objectives

GuidelinesGuidelines

Action LevelsAction Levels

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IntroductionIntroduction

Do all of these terms mean the same thing?Do all of these terms mean the same thing?

Are the numerical values comparable?Are the numerical values comparable?

Can a single value be used for each chemical?Can a single value be used for each chemical?

What is the best approach based on current What is the best approach based on current science?science?

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Water Quality StandardsWater Quality Standards

Consist of two partsConsist of two parts

Designated UseDesignated Use

Water Quality Criteria to protect that Water Quality Criteria to protect that useuse

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Water Quality StandardsWater Quality Standards

Designated UsesDesignated Uses

Aquatic lifeAquatic life

Warm water/cold waterWarm water/cold water

Survival/propagationSurvival/propagation

Human HealthHuman Health

Drinking/non-drinkingDrinking/non-drinking

WildlifeWildlife

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Water Quality StandardsWater Quality Standards

Designated Uses (continued)Designated Uses (continued)

RecreationRecreation

AgriculturalAgricultural

IndustrialIndustrial

Existing vs. attainable usesExisting vs. attainable uses

Use attainability analysisUse attainability analysis

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Water Quality CriteriaWater Quality Criteria

Narrative: “No toxics in toxic Narrative: “No toxics in toxic amounts”amounts”

Numeric: Chemical concentrations to Numeric: Chemical concentrations to protect designated usesprotect designated uses

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Water Quality CriteriaWater Quality Criteria

Ohio WQC for Total Chromium (ug/l)Ohio WQC for Total Chromium (ug/l)

Aquatic life (acute) Aquatic life (acute) 1,800 1,800

Aquatic life (chronic) Aquatic life (chronic) 86 86

Human Health (drinking)Human Health (drinking) 140 140

Human Health (non-drinking) Human Health (non-drinking) 14,00014,000

AgriculturalAgricultural 100 100

Annex 1 Specific ObjectiveAnnex 1 Specific Objective 50 50

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Water Quality CriteriaWater Quality Criteria

Three ComponentsThree Components

Magnitude (How much?)Magnitude (How much?)

Duration (How long?)Duration (How long?)

Frequency (How often?)Frequency (How often?)

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Aquatic Life CriteriaAquatic Life Criteria

US EPA GuidelinesUS EPA Guidelines

Virtually unchanged since 1985Virtually unchanged since 1985

Stringent data requirements (e.g., 8 Stringent data requirements (e.g., 8 families)families)

Basis for GLWQG, most statesBasis for GLWQG, most states

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Aquatic Life CriteriaAquatic Life Criteria

MagnitudeMagnitude

Protect 95th percentile most sensitive Protect 95th percentile most sensitive speciesspecies

Acute and chronic criteriaAcute and chronic criteria

May be expressed as function of water May be expressed as function of water hardness, pHhardness, pH

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Aquatic Life CriteriaAquatic Life Criteria

Key Drivers of MagnitudeKey Drivers of Magnitude

Acute toxicity of four most sensitive Acute toxicity of four most sensitive speciesspecies

Number of speciesNumber of species

Acute-chronic ratioAcute-chronic ratio

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Aquatic Life CriteriaAquatic Life Criteria

DurationDuration

Acute: 1-hour averageAcute: 1-hour average

Chronic: 4-day averageChronic: 4-day average

How do these compare to actual exposures in How do these compare to actual exposures in toxicity tests?toxicity tests?

Are these appropriate for all chemicals?Are these appropriate for all chemicals?

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Aquatic Life CriteriaAquatic Life Criteria

FrequencyFrequency

Once every three yearsOnce every three years

Basis?Basis?

Is it dependent on magnitude of exceedance?Is it dependent on magnitude of exceedance?

Is this appropriate for all chemicals?Is this appropriate for all chemicals?

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Aquatic Life CriteriaAquatic Life Criteria

Site-Specific CriteriaSite-Specific Criteria

Recalculation Recalculation

Water Effect RatioWater Effect Ratio

Resident speciesResident species

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Human Health CriteriaHuman Health Criteria

US EPA GuidelinesUS EPA Guidelines

Updated in 2000Updated in 2000

Similar to GLWQCSimilar to GLWQC

Carcinogens and non-carcinogensCarcinogens and non-carcinogens

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Human Health CriteriaHuman Health Criteria

Key Drivers of MagnitudeKey Drivers of Magnitude

Fish consumption rateFish consumption rate

BAF vs. BCFBAF vs. BCF

Cancer risk levelCancer risk level

Uncertainty factorsUncertainty factors

Relative source contributionRelative source contribution

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Human Health CriteriaHuman Health Criteria

DurationDuration

Lifetime (70 years)Lifetime (70 years)

FrequencyFrequency

Not expressedNot expressed

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Wildlife CriteriaWildlife Criteria

Introduced in GLWQGIntroduced in GLWQG

Protect birds and mammals that Protect birds and mammals that consume fishconsume fish

Similar to human health proceduresSimilar to human health procedures

Limited data, few criteriaLimited data, few criteria

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Emerging CriteriaEmerging Criteria

Aquatic life criteria for metals Aquatic life criteria for metals

DissolvedDissolved

Biotic Ligand ModelBiotic Ligand Model

Tier 2 “values”Tier 2 “values”

Nutrient criteriaNutrient criteria

Tissue-based criteriaTissue-based criteria

Sediment criteria/guidelinesSediment criteria/guidelines

BiocriteriaBiocriteria

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Key Considerations for Deriving Key Considerations for Deriving CriteriaCriteria

What are you trying to protect?What are you trying to protect?

Appropriate and attainable usesAppropriate and attainable uses

Individuals or populations?Individuals or populations?

What is actual exposure?What is actual exposure?

What is “acceptable” level of risk?What is “acceptable” level of risk?

Where do criteria apply?Where do criteria apply?

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Key Considerations for Deriving Key Considerations for Deriving CriteriaCriteria

National, regional, watershed, or site-specific?National, regional, watershed, or site-specific?

What chemicals do you set criteria for?What chemicals do you set criteria for?

What do you do when minimum data requirements What do you do when minimum data requirements are not met?are not met?

How do you assess compliance?How do you assess compliance?

Many of these are policy, rather than scientific issues.Many of these are policy, rather than scientific issues.

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Characteristics of “Quality” CriteriaCharacteristics of “Quality” Criteria

RobustRobust

Based on extensive data base across range of species to Based on extensive data base across range of species to minimize effects of statistical analyses and uncertainty factorsminimize effects of statistical analyses and uncertainty factors

LocalizedLocalized

Appropriate for ecosystem and designated useAppropriate for ecosystem and designated use

FlexibleFlexible

Adjustable using reasonable site-specific proceduresAdjustable using reasonable site-specific procedures