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EPA Nutrient Criteria Mandates EPA Nutrient Criteria Mandates and Strategies to Avoid and Strategies to Avoid
Misallocation of State ResourcesMisallocation of State ResourcesJohn C. HallJohn C. Hall
Hall & AssociatesHall & AssociatesWashington, D.C.Washington, D.C.
PERSISTENT REGULATORY PERSISTENT REGULATORY THEMESTHEMES
• Federal Program Expanding Reach (via Policy)
• Complex Science In Search of Simple Solutions
• Economic Impacts-Dwindling Consideration
• State Resources Stressed/Decisions Data Poor
• Environmental Groups Controlling Judicial Agenda
Observation: Staying on the sidelines isn’t helping
SIGNIFICANT DEVELOPMENTSSIGNIFICANT DEVELOPMENTS•• Nutrient PetitionsNutrient Petitions
----Secondary Treatment Secondary Treatment ----Gulf of Mexico TMDL/StandardsGulf of Mexico TMDL/Standards----Florida Nutrient StandardsFlorida Nutrient Standards----Wisconsin NOIWisconsin NOI
•• State/EPA Call to Action Report/IG ReportState/EPA Call to Action Report/IG Report
•• Chesapeake Bay Initiative/LegislationChesapeake Bay Initiative/LegislationObjectiveObjective: Mandate State: Mandate State--ofof--thethe--Art Nutrient Removal for All; Art Nutrient Removal for All;
EPA Seems Favorably DisposedEPA Seems Favorably Disposed
FLORIDA WQS PROPOSALFLORIDA WQS PROPOSAL
•• Employs Unprecedented MethodsEmploys Unprecedented Methods
•• EPA Agreed No Cause/Effect Demonstration for EPA Agreed No Cause/Effect Demonstration for Streams/Canals Set Low WQS AnywayStreams/Canals Set Low WQS Anyway
•• Used Used ““Impact on Downstream WatersImpact on Downstream Waters”” as Basis for as Basis for Lowering Stream Standards Lowering Stream Standards –– Generic TMDLGeneric TMDL
•• Regulated Nutrients BELOW Natural BackgroundRegulated Nutrients BELOW Natural Background
•• Applies Chl Applies Chl ‘‘aa’’ and and BOTH TN/TP IndependentlyBOTH TN/TP Independently for for All WatersAll Waters
THE CHALLENGE WE FACETHE CHALLENGE WE FACE
•• Refocus Expenditures On Truly Beneficial Refocus Expenditures On Truly Beneficial Environmental Projects and Remediation Environmental Projects and Remediation EffortsEfforts
•• Promote the Most CostPromote the Most Cost--Effective Approach Effective Approach and Consideration of Siteand Consideration of Site--Specific ImpactsSpecific Impacts
•• Develop Solutions Develop Solutions BeforeBefore OneOne--SizeSize--FitsFits--All All ImposedImposed
EPA GUIDANCE ON ALGAL EPA GUIDANCE ON ALGAL GROWTH RELATIONSHIPGROWTH RELATIONSHIP
“The difficulty associated with understanding predictive relationships between nutrient loading and algal biomass is perhaps the biggest challenge to establishing meaningful nutrient criteria.”
(2000 Nutrient Criteria Technical Guidance Manual–Rivers and Streams at 73)
1996 1997 1998 1999 2000 2001 2002 2003
2004 2005 2006 2008 20092007
EPA Nutrient Criteria Development Timeline
EPA - Ecoregional Approach to Nutrient Criteria Development
EPA Publishes Approach for Lakes, Rivers and
Streams
Dissolved Oxygen Endpoint
Nuisance Algae Endpoint Macroinvertebrate Endpoint
PADEP/EPA issue draft Nuisance periphyton TMDLs
using Dodds regressionEPA withdraws Nuisance Algae TMDLs (science
flawed)
EPA Memo to States on Nutrient Criteria Development (5/25)
ASIWPCA Letter to EPA (7/18)
EPA/PADEP unveil revised
endpoints applying Empirical Approach
for PA TMDLs
SAB Review request
Overview of Water Quality Model Kinetics
ASIWPCA LETTERASIWPCA LETTER(July 18, 2007)(July 18, 2007)
““Many States are Many States are failing to find a strong linkagefailing to find a strong linkage between between the EPA recommended cause variables (N and P) and the EPA recommended cause variables (N and P) and response variables ... These problems can only lead to response variables ... These problems can only lead to miscues in impairment identification and miscues in impairment identification and misdirection of misdirection of scarce management and implementation resourcesscarce management and implementation resources..””
““Because no two waterbodies are the same, siteBecause no two waterbodies are the same, site--specific specific evaluations and, most probably, evaluations and, most probably, sitesite--specific criteria are specific criteria are requiredrequired that reflect their uniqueness and protect their that reflect their uniqueness and protect their natural trophic tendencies.natural trophic tendencies.””
Suggested possible technologySuggested possible technology--based approachbased approach
So what was EPASo what was EPA’’s response?s response?
PLANT GROWTHPLANT GROWTH
2008 EPA APPROACH TO STREAM 2008 EPA APPROACH TO STREAM NUTRIENT STANDARDSNUTRIENT STANDARDS
•• Ignore Plants, Assume Nutrients Directly Impair Ignore Plants, Assume Nutrients Directly Impair Macroinvertebrate/Algal CommunitiesMacroinvertebrate/Algal Communities
•• Claim Literature Review Sufficient to Impose Claim Literature Review Sufficient to Impose Stringent Limits (Stringent Limits (no siteno site--specific cause/effect specific cause/effect evaluation)evaluation)
•• Conditional Probability Conditional Probability ““ConfirmsConfirms”” Stressor Stressor Relationship (low RRelationship (low R22 acceptable acceptable -- 0.1)0.1)
•• EPA Wants Nationwide Implementation of New EPA Wants Nationwide Implementation of New MethodsMethods
2008 NUTRIENT TMDLs2008 NUTRIENT TMDLsTP Limit/Reduction RequirementsTP Limit/Reduction Requirements
TMDL WWTP MS4
Goose Creek 0.04 mg/L(>98% reduction)
53.9% Reduction
Indian Creek ~0.05 mg/L(90-97% reduction)
62-70% Reduction
Southampton Ck 0.08 mg/L(92% reduction)
>90% Reduction
Paxton Creek CSO Long Term Control Plan
89% Reduction
Sawmill Run 98% Reduction from CSOs
55-96% Reduction
CONSEQUENCES OF TMDLSCONSEQUENCES OF TMDLS
•• NonNon--Point Load Reduction Targets UnattainablePoint Load Reduction Targets Unattainable
•• Freeze on New Projects/New ConnectionsFreeze on New Projects/New Connections
•• At Least $200 Million in Local ExpendituresAt Least $200 Million in Local Expenditures
•• Additional Round of Reductions Will Be MandatedAdditional Round of Reductions Will Be Mandated
•• No Material Change in Ecological Condition BecauseNo Material Change in Ecological Condition BecauseNutrients Were Not Causing the ImpairmentsNutrients Were Not Causing the Impairments
OVERVIEW OF EPA SCIENCE OVERVIEW OF EPA SCIENCE ADVISORY BOARD DECISIONADVISORY BOARD DECISION
PRESENTATION TO SABPRESENTATION TO SAB•• How We Got HereHow We Got Here –– John C. HallJohn C. Hall
•• Major ConcernsMajor Concerns –– Dominic M. Di ToroDominic M. Di Toro
•• Empirical ApproachEmpirical Approach –– William T. HallWilliam T. HallEvaluation Evaluation
•• Appropriate Methods ToAppropriate Methods To –– Thomas W. GallagherThomas W. GallagherReduce UncertaintyReduce Uncertainty
•• Recommended ApproachRecommended Approach –– Dominic M. Di ToroDominic M. Di Toro
NATIONAL GUIDELINES NATIONAL GUIDELINES PRINCIPLESPRINCIPLES
•• Established at Level Established at Level ““Necessary to Protect UsesNecessary to Protect Uses””•• Must Ensure Use Protection with Small Probability of Must Ensure Use Protection with Small Probability of
Considerable Over/UnderConsiderable Over/Under--ProtectionProtection•• Only Derive Criteria if Adequate Appropriate Data are Only Derive Criteria if Adequate Appropriate Data are
Available to Provide Reasonable Confidence in CriteriaAvailable to Provide Reasonable Confidence in Criteria•• Criteria Must Be Consistent With Sound Scientific EvidenceCriteria Must Be Consistent With Sound Scientific Evidence--
Demonstrated Dose/ResponseDemonstrated Dose/Response•• Must Account for Major Factors Influencing Pollutant ImpactMust Account for Major Factors Influencing Pollutant Impact•• Confounded Studies Should Not Be Used for Criteria Confounded Studies Should Not Be Used for Criteria
DerivationDerivation
AMMONIA CRITERIAEffect of pH
EPA 1998 Update of Ambient Water Quality Criteria for AmmoniaEPA 822-R-98-008 August 1998
REGRESSIONS PROVIDE NO REGRESSIONS PROVIDE NO SOUND BASISSOUND BASIS
Empirical Approaches for Nutrient Criteria DerivationUSEPA Office of WaterScience Advisory Board Review DraftAugust 17, 2009
More More
PreciselyPrecisely
There is No There is No
Mechanistic Mechanistic
RelationshipRelationship
Empirical Approaches for Nutrient Criteria Derivation
BOD CRITERIA BOD CRITERIA –– PREDICT DO PREDICT DO All StreamsAll Streams
Total Phosphorus Vs. River Chlorophyll(From Van Nieuwenhuyse, E. E. and Jones, J.
R., 1996)
Chl-a=30 ug/L
TP=60 ug/L
TP=600 ug/L
Total Phosphorus Vs. Benthic Chlorophyll-‘a’(From Dodds. W. K., Smith, V. H., and
Lohman, K., 2006)
TP=20 ug/L
TP=500 ug/L
CONDITIONAL PROBABILITYEPT Taxa; Change Point = 38 ug/L
CONDITIONAL PROBABILITYTP < 0.1 MG/L
Raw data scatter plot
Conditional Probability Plot
Change Point > 95 ug/L
0.00.10.20.30.40.50.60.70.80.91.0
0.001 0.01 0.1 1TP (mg/L)
EPT
Taxa
< 8
02468
101214161820
0.001 0.01 0.1 1TP (mg/L)
EPT
Taxa
MBSS EPT DATAANALYSIS OF VARIANCE
05
101520253035
4 - 6 7 - 8 9 - 9 10 - 10 11 - 11 12 - 12 13 - 14 15 - 16 17 - 19 20 - 24 25 - 29 30 - 39 40 - 59 61 - 97 107 - 682
Obs
erva
tions
0
2
4
6
8
10
12
14
16
18
4 - 6 7 - 8 9 - 9 10 - 10 11 - 11 12 - 12 13 - 14 15 - 16 17 - 19 20 - 24 25 - 29 30 - 39 40 - 59 61 - 97 107 - 682
Bin (TP Range - ug/L)
Avg
EPT
No Significant Difference; p=0.40Significant; p=0.03
SITE-SPECIFIC DATAGOOSE CREEK
Goose Creek/Chester Creek Periphyton Data versus TP Concentration
0
100
200
300
GC-1 GC-2 GC-3 GC-4 CC-1 CC-2 CC-3 CC-4 CC-5Station
Chl
-a (m
g/m
2 )
0.0
0.5
1.0
1.5
2.0
2.5
3.0
TP (m
g/L)
Chl-a AvgTP
EPA Nuisance Algae Threshold
TP Not Causing Nuisance Periphyton Growth
PAXTON CREEK(Concrete Lined Channel)
PAXTON CREEKPaxton Creek - 2007 SRBC Data
Growing Season Average
0.00
0.05
0.10
0.15
0.20
0.25
1 3 2 4 5 6 7 8 9 10 11 12 HW
Station
TP (m
g/L)
TP Impaired Segments Sediment Impaired Segments Un-Impaired Segments
TP WQS - 0.025 mg/L
Concrete Channel
Paxton Creek - 2006-2007 SRBC Data
y = 0.10x - 4.76R2 = 0.47
0
2
4
6
8
10
12
14
16
0 20 40 60 80 100 120 140 160 180 200
Habitat Score
EPT
Taxa
Habitat Impaired
Sediment Impaired
Un-Impaired
No TP: Impairment Relationship
SAB CONCLUSION OVERVIEWSAB CONCLUSION OVERVIEW
•• Regression Approach Not Scientifically Defensible; Lacks Regression Approach Not Scientifically Defensible; Lacks Cause/Effect DemonstrationCause/Effect Demonstration
•• Need to Confirm Need to Confirm ““ImpairmentImpairment”” Thresholds Are Thresholds Are Biologically SignificantBiologically Significant
•• Need to Account for Factors Influencing Nutrient Need to Account for Factors Influencing Nutrient Dynamics and Invertebrate MetricsDynamics and Invertebrate Metrics
•• Loading Approach May Be Better Than ConcentrationLoading Approach May Be Better Than Concentration
•• Failure to Consider SiteFailure to Consider Site--Specific Data May Yield Specific Data May Yield Inappropriate ResultsInappropriate Results
•• Conditional Probability Unreliable For Criteria SelectionConditional Probability Unreliable For Criteria Selection
GENERAL OBSERVATION ON USE OF GENERAL OBSERVATION ON USE OF GUIDANCE GUIDANCE
SAB ReportSAB Report
• The Committee finds that improvements in the Guidance are needed prior to implementation to enable development of technically defensible criteria (at 2)
• A clear framework for statistical model selection is needed. This framework should include: 1) an assessment of whether analysis indicate that the stressor-response approach is appropriate; 2) selection criteria to establish models of cause/effect and direct/indirect relationships between stressors and responses; 3) consideration of model relevance to known mechanisms and existing conditions; 4) establish of biological relevance; and 5) ability to predict probability of meeting designated use categories. (at 30; exec sum at xiv)
BIOLOGICAL SIGNIFICANCE/USE BIOLOGICAL SIGNIFICANCE/USE IMPAIRMENT THRESHOLD RELATIONSHIPIMPAIRMENT THRESHOLD RELATIONSHIP
SAB ReportSAB Report
• The Committee emphasizes the importance of choosing the biological endpoints (i.e., response variables) that respond specifically to nutrients. We note that responses of benthic indices can be related to many types of stress. We question why periphyton would not be a better receptor to measure. (at 15)
• The use of non-parametric change point analysis and discontinuous regression analysis must be associated with biological significance and the designated uses to be protected by numeric nutrient criteria. …However, although these methods may be able to identify and characterize breakpoints, such breakpoints may not necessarily have any biological significance, nor will they necessarily be related to designated uses that are to be protected by numeric nutrient criteria. Use of these methods must be associated with designated uses. (at 22)
CAUSE AND EFFECT DEMONSTRATION CAUSE AND EFFECT DEMONSTRATION NECESSARYNECESSARY
SAB ReportSAB Report
• [T]he final document should clearly state that statistical associations may not be biologically relevant and do not prove cause and effect. (at 2) Without a mechanistic understanding and a clear causative link between nutrient levels and impairment, there is no assurance that managing for particular nutrient levels will lead to the desired outcome. (at 4); The Guidance needs to clearly indicate that the empirical stressor-response approach does not result in cause-effect relationships; it only indicates correlations that need to be explored further. (at 39)
• Large uncertainties in the stressor-response relationship and the fact that causation is neither directly addressed nor documented indicate that the stressor-response approach using empirical data cannot be used in isolation to develop technically defensible water quality criteria that will “protect against environmental degradation by nutrients.” (at 37; see also 22)
Consideration of Factors Influencing Consideration of Factors Influencing Nutrient Dynamics/Impairment MetricNutrient Dynamics/Impairment Metric
SAB ReportSAB Report
• In order to be scientifically defensible, empirical methods must take into consideration the influence of other variables. …The statistical methods in the Guidance require careful consideration of confounding variables before being used as predictive tools. … Without such information, nutrient criteria developed using bivariate methods may be highly inaccurate. (at 22)
• For criteria that meet EPA’s stated goal of “protecting against environmental degradation by nutrients,” the underlying causal models must be correct. Habitat condition is a crucial consideration in this regard (e.g., light [for example, canopy cover], hydrology, grazer abundance, velocity, sediment type) that is not adequately addressed in the Guidance. Thus, a major uncertainty inherent in the Guidance is accounting for factors that influence biological responses to nutrient inputs. Addressing this uncertainty requires adequately accounting for these factors in different types of water bodies. (at 36,37) Numeric nutrient criteria developed and implemented without consideration of site specific conditions can lead to management actions that may have negative social and economic and unintended environmental consequences without additional environmental protection. (at 37)
STREAM CONSIDERATIONSSTREAM CONSIDERATIONSSAB ReportSAB Report
• The examples provided in the Guidance generally do not demonstrate a strong nutrient stressor linkage to beneficial use impairment. The stream examples show very weak correlations that have high levels of uncertainty, and lump data from distinctly different ecosystems where multiple factors in addition to nutrients will contribute to biotic responses. (at 14,15)
• Single variable stressor-response relationships (e.g., those derived using the simple linear regression approach discussed in the Guidance) that explain a substantial amount of variation are likely to be uncommon for most aquatic ecosystems (in particular, streams). (at 10); As previously discussed, relationships for streams may be more complex than for lakes and must account for multiple stressors/conditions and/or stream ‘types’or conditions, and then be applied appropriately. (at 23)
LOADING VERSUS CONCENTRATION LOADING VERSUS CONCENTRATION APPROACH APPROACH
SAB ReportSAB Report
• A basic conceptual problem concerning selection of nutrient concentrations as stressor variables (as illustrated in the Guidance) is that nutrient concentrations directly control only point-in-time, point-in-space kinetics, not peak or standing stock plant biomass. Plant biomass is driven by nutrient supply rates (i.e., nutrient mass loads). Ambient nutrient concentrations are not necessarily good surrogates for nutrient mass loads. Relationships between nutrient mass loads and ambient nutrientconcentrations are highly system-specific and depend on many factors including inflows, hydrology, bathymetry, sediment-water exchanges and chemical-biological processes. Consequently, there may be many systems for which nutrient concentrations will not be appropriate stressor variables. For such systems it may be more appropriate, and scientificallydefensible, to use site-specific mechanistic models incorporating loading to determine the nutrient controls required to attain designated uses. (at 11)
RECENT REGION I ACTIONSRECENT REGION I ACTIONS
•• Applying 1976 Applying 1976 ““Red BookRed Book”” Criteria (0.1 mg/l TP) and EcoCriteria (0.1 mg/l TP) and Eco--regional regional Targets (e.g., 0.63 ug/l chl Targets (e.g., 0.63 ug/l chl ‘‘aa’’) as Adopted Instream Standards) as Adopted Instream Standards
•• Applying LongApplying Long--Term TP/chl Term TP/chl ‘‘aa’’ Targets to 7/Q/10 Conditions Targets to 7/Q/10 Conditions
•• Making Decisions Without Modeling or Any Demonstrated RelationshMaking Decisions Without Modeling or Any Demonstrated Relationship ip Between Nutrient Levels and Use ImpairmentsBetween Nutrient Levels and Use Impairments
Keene, NH Keene, NH –– 0.2 mg/l limit0.2 mg/l limitJaffrey, NH Jaffrey, NH –– 0.16 mg/l TP0.16 mg/l TP
•• Ignoring State Objections on Proper Narrative Criteria ApplicatiIgnoring State Objections on Proper Narrative Criteria Applicationon
•• Great Bay Great Bay –– 0.25 mg/l TN Criteria (seagrass protection); Based on 0.25 mg/l TN Criteria (seagrass protection); Based on Simplified Regression Analyses SAB CriticizedSimplified Regression Analyses SAB Criticized
The scientific basis of all of these decisions is extremely poorThe scientific basis of all of these decisions is extremely poor
SUGGESTED STRATEGY TO SUGGESTED STRATEGY TO PROTECT MUNICIPAL INTERESTSPROTECT MUNICIPAL INTERESTS
•• Comment on Key Federal Proposals/Science ChangesComment on Key Federal Proposals/Science Changes
•• Support State Actions on Developing Reasonable Nutrient Support State Actions on Developing Reasonable Nutrient Standards and Implementation MethodsStandards and Implementation Methods
•• Identify Impairment ThresholdsIdentify Impairment Thresholds
•• Focus on Limiting NutrientFocus on Limiting Nutrient
•• Get Averaging Period CorrectGet Averaging Period Correct
•• Assist in Development of Necessary Technical Information; Assist in Development of Necessary Technical Information; If You DonIf You Don’’t Do It, Conservative Assumptions Applied t Do It, Conservative Assumptions Applied
•• Promote Alternative Regulatory Approaches That Focus Promote Alternative Regulatory Approaches That Focus Resources on Priority Problems/Least Cost SolutionsResources on Priority Problems/Least Cost Solutions
For More Information:For More Information:
John C. HallJohn C. HallHall & AssociatesHall & Associates
1101 151101 15thth Street NWStreet NWSuite 203Suite 203
Washington, D.C. 20005Washington, D.C. 20005202202--463463--11661166
jhall@[email protected]