Transcript Water Quality Standards-based Effluent Limitations: Fate

Water Quality Standards-based
Effluent Limitations:
Fate versus Self-determination
Bill Van Derveer
Objectives
• Describe water quality standards (WQS) development
process
• Characterize potential effects of water quality
standards-based effluent limits (WQSBELs) on
WWTFs, ratepayers, & industrial users
• Describe how WQS can be refined to increase sitespecificity and achieve statutory objectives
• Demonstrate benefits of discharger participation in
WQS adoption processes
• Propose an approach for discharger involvement in
WQS adoption processes
Environmentalists
Premise
Ratepayers
Ratepayers
Convert
a Societal
Waste to a
Resource
Provide
Service at
Minimal Cost
& Impact
Statutes/Regulations
Industrial Users
Regulators
Ratepayer, Environmental,
& Industrial Objectives
Achieved
Involvement in WQS process facilitates objectives achievement
Avoiding
Environmental
Protection
Fate vs. Self-determination
Conventional Definitions
Fate
An inevitable and often
adverse outcome
Self-determination
Determination of one's own
fate or course of action
WQS Context Definitions
Fate
WQS defined by regulators,
environmental groups, and
special interests, although
WWTF may be most affected
through WQSBELs
Self-determination
WWTF participation yields
WQS that reflect site-specific
conditions and assure
environmental protection:
– Improving WQSBEL accuracy
– Controlling WWTF cost/risk
Pathway to WQSBELs
Federal Clean
Water Act
National Water
Quality Criteria
State Water
Quality Act
State Water
Quality Standards
State Use
Classifications
Segment Water
Quality Standards
Segment Use
Classifications
TMDLs &
Antidegradation
Reasonable
Potential Analysis
WQSBELs
Parameters Subject to WQSBELs
•
•
•
•
•
Ammonia
Metals/metalloids
Some anions (e.g., sulfate & chloride)
Nutrients (nitrogen & phosphorus)
Future
– Organic compounds (e.g., consumer pesticides)
– Pharmaceuticals & personal care products (e.g., antibiotics)
– Endocrine distruptors
WWTFs are not
designed to
treat most
WQSBEL
parameters
Potential Effects of WQSBELs on
WWTFs
No Effect
(WQSBEL >>
Effluent Conc.)
Increased
Noncompliance
Risk
Require
Capital
Improvements
WQSBELs
Reduced
Operational
Flexibility
Decreased
Infrastructure
Value/Life
Stringent
Pretreatment
Local Limits
Sophisticated
Compliance
Systems
Anatomy of a WQSBEL
Stream +
Effluent
Flow
Effluent
Limit
Water
Quality
Standard
Stream
Low
Flow
QrCr  QsCs
Cd 
Qd
Effluent
Design
Flow
Stream
Background
Regional Importance of WQSBELs
• WQS is only parameter in WQSBEL equation that can
be significantly modified
• Effluent dominated/dependent waters common in
arid/semi-arid West
– WQS applied with little or no dilution
Why Refine WQS?
• Clean Water Act: “Restore & maintain the physical,
chemical, & biological integrity of the Nation’s waters”
• Aquatic life WQS tend to be most stringent
• Most WQS are one-size-fits-all
– Intended to protect nearly all species in U.S.
• Small toxicological data sets for most pollutants
• Driven by most sensitive species
• Data characteristics yield conservative estimates of “safe”
concentrations
– Limited site-specific adjustment
• Hardness-based metals
• pH- & temperature-based ammonia
• National criteria may be a poor fit for some sites
– Regulatory provisions for improving accuracy of WQS at the
site level
Potential Differences Between
National Database & Specific Site
•
•
•
•
•
Simple laboratory exposures vs. complex ecosystem
Different species composition & relative sensitivities
Constituents of natural waters effect bioavailability
Variation in pollutant form or species
Aquatic cycling processes & food web structure
–
–
–
–
–
Waterbody type: Streams vs. Lakes/Reservoirs
Habitat type: Erosional vs. depositional
Hydraulic residence time
Exposure routes, frequencies & duration
Bioaccumulation potential
WQS Refinement Opportunities for
a Hypothetical Population of Sites
True Protective Concentration
40
WQS Refinement
Candidates
30
20
10
National
Criterion
0
A B C D E F G H I
J L K M N O P Q R S T
Site
WQS Refinement Alternatives
• EPA Recalculation Procedure
• EPA Resident Species Procedure
• EPA Indicator Species / Water Effect Ratio Procedure
– Biotic ligand model
• Other scientific basis
– Ambient-based WQS
• Natural or uncontrollable human-caused conditions
– Seasonal implementation or modification (ELS)
– Temporary modification
• Uncertainty regarding appropriate WQS
• Re-segmentation
– To focus WQS refinement efforts
• Change designated use
WQSBEL Sensitivity Analysis
40
~4.2:1
Greater than 1:1
return in WQSBEL
Effluent Limit (ug/L)
35
30
~1.6:1
25
~1.3:1
20
15
10
5
Minimum return is 1:1
0
0
5
10
15
Water Quality Standard (ug/L)
1 mgd
5 mgd
10 mgd
Assumes: Stream low flow = 5 cfs, Stream background = 2 ug/L
20
Recommended Approach &
Resource Allocation
Segment  Federal  State  Segment
• Receiving water monitoring (15% of resources)
Objective
• Understand physical, chemical & biological characteristics
– USGS partnership or watershed association
• National criteria development, adoption, or
modification (10% of resources)
Objectives
• Ensure adequacy of underlying data, analysis, & assumptions
• Promote flexibility for subsequent refinement
– Monitor Federal initiatives
• Federal/trade publications, web sites, & email distributions
– Influence Federal actions
• Provide input to National/regional trade organizations &
coalitions
• Prepare independent comments
Recommended Approach (cont’d)
• Statewide WQS development, adoption, or
modification (35% of resources)
Objectives
• Ensure relevance of National criteria to statewide conditions
• Ensure adequacy of State’s underlying data, analysis, &
assumptions
• Ensure flexibility for site-level refinement
– Monitor Statewide initiatives
• Review State publications and web sites
• Participate in trade associations/councils
• Attend informational hearings
– Influence Statewide actions
• Participate in stakeholder groups
• Participate in trade associations/councils & coalitions
• Submit independent comments and/or provide testimony
Recommended Approach (cont’d)
• Segment WQS adoption or modification
(40% of resources)
Objectives
• Ensure WQS are protective but not over-protective
• Secure site-specific refinement if appropriate
– Plan for upcoming hearings
• Define potential issues
• Identify stakeholders & their perspectives
– Perform site-specific studies
• Plan & execute in advance of hearings whenever possible
• Promote stakeholder involvement
– Participate in hearings
• Seek regulatory agency acceptance in prehearing statement
• Provide independent written & oral testimony
Return on Investment Analysis
4.0
Relatively small cost avoidance = positive ROI
Return on Investment
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
$1,000
$10,000
$100,000
$1,000,000
6-Year WWTF Cost Avoidance
$50,000/yr
$100,000/yr
$200,000/yr
$10,000,000
Potential Outcomes
• Relevant National/statewide standards
– Refinement is unnecessary
• Site-specific WQS refinement
– Less stringent: WWTF, ratepayer, & industrial impacts reduced
– Refinement is effort unsuccessful
– More stringent: greater environmental protection justified
• Regardless of WQS refinement success
– Improved positioning for permit renewal
• More data for reasonable potential analysis, antidegradation
reviews, & WQSBELs
– Greater understanding of compliance risks/priorities
• Information to refine capital improvement plans & budget
– Data availability of other regulatory issues
• 305B reporting, 303(d) list issues, & TMDL development
Conclusions
• WQSBELs can have manifold impacts on WWTFs,
ratepayers, & industrial users
• Involvement in WQS process allows WWTFs to
(partially) determine their regulatory fate
• National or statewide WQS can be a poor fit to a
given site
• Site-specific WQS refinement can help manage
WWTF impacts and achieve statutory objectives
• Portfolio of WWTF efforts is recommended
– Greatest emphasis on segment & statewide levels
• Significant positive return on investment is likely
• Yields peripheral benefits regardless of success at
WQS refinement