What's New for Whole Effluent Toxicity (WET) - PowerPoint PPT Presentation

About This Presentation
Title:

What's New for Whole Effluent Toxicity (WET)

Description:

Whole Effluent Toxicity (WET) = total toxic (poisonous) effect of an effluent on ... Nothing. Annual WET monitoring (permit app requirement) WET Monitoring ... – PowerPoint PPT presentation

Number of Views:224
Avg rating:3.0/5.0
Slides: 41
Provided by: dimo6
Learn more at: https://www.mi-wea.org
Category:

less

Transcript and Presenter's Notes

Title: What's New for Whole Effluent Toxicity (WET)


1
What's New for Whole Effluent Toxicity (WET)
  • Bill Dimond
  • MDEQ Aquatic Toxicology Laboratory

2
Outline
  • Introduction to WET
  • How MDEQ regulates WET in the NPDES Permit
    Program
  • Whats new
  • Maximizing Effect/Minimizing Cost
  • MDEQ Aquatic Toxicology Laboratory

3
Introduction to WET
  • Whole Effluent Toxicity (WET) total toxic
    (poisonous) effect of an effluent on aquatic
    animals
  • Measured by WET test
  • Aquatic animals exposed to effluent
  • Measures
  • Mortality
  • Growth or reproduction (sub-lethal effects)

4
Introduction to WET
  • Bay Harbor CKD Leachate

5
Introduction to WET
  • WET Test

6
Introduction to WET
  • Definitions
  • TUa acute toxic unit. Amount of acute toxicity
    measured
  • TUc chronic toxic unit. Amount of chronic
    toxicity measured
  • Toxic units vary from 0 (not toxic) to as many as
    1,000 (paper product spill) or more

7
Introduction to WET
  • WET test animals
  • Fathead minnow
  • Daphnia magna
  • Ceriodaphnia dubia

8
Introduction to WET
  • WET test animals are surrogates for all animals
    in the aquatic ecosystem

9
Introduction to WET
  • Objective is to prevent toxicity to aquatic life

10
Introduction to WET
  • All aquatic life (mussel)

K. S. Cummings of the Illinois Natural History
Survey
11
Introduction to WET
  • Something new Ceriodaphnia is not the most
    sensitive aquatic animal!

12
Introduction to WET
  • More sensitive to sulfates Amphipod Hyalella
    azteca

13
Introduction to WET
  • More sensitive to sodium chloride, ammonia
  • (mussels)

Barnhart, M. C.  2006. Unio Gallery 
http//unionid.missouristate.edu.  Accessed 4 11
07
14
Introduction to WET
  • Mussel egg sacs

Barnhart, M. C.  2006. Unio Gallery 
http//unionid.missouristate.edu.  Accessed 4 11
07
15
Introduction to WET
Barnhart, M. C.  2006. Unio Gallery 
http//unionid.missouristate.edu.  Accessed 4 11
07
16
Introduction to WET
Barnhart, M. C.  2006. Unio Gallery 
http//unionid.missouristate.edu.  Accessed 4 11
07
17
Introduction to WET
  • Something new Ceriodaphnia is not the most
    sensitive aquatic animal!
  • More than ever, Michigan considers Ceriodaphnia
    dubia to be a reasonable surrogate WET test
    organism

18
Michigan Regulation of WET
  • WET regulation required by rule
  • R1057(1), Michigan Natural Resources and
    Environmental Protection Act
  • Toxics shall not be present at levels which are
    or may become injurious...
  • R1057(6)
  • Whole-effluent toxicity requirements may be
    used to ensure... requirements are met

19
Michigan Regulation of WET
  • R1219 Whole Effluent Toxicity
  • Interprets 1057(6) narrative criterion
  • Allows 1 TUa at point of discharge
  • Allows 1 TUc after mix

20
R1219 Flow Diagram
MIXED
1.0 TUc
FLOW
MIXING
1.0 TUa
DISCHARGE POINT
21
Michigan Regulation of WET/Recent Changes
  • Reasonable Potential (RP) (2000)
  • Statistical determination of potential to exceed
    allowable WET level
  • Comparison of worst-case toxicity x multiplier
    against allowable WET
  • A finding of RP requires a WET Limit by Rule

22
Michigan Regulation of WET/Recent Changes
  • Reasonable Potential (RP)
  • Only representative data are to be used
  • More tests reduce uncertainty, and therefore
    multiplier
  • But if any representative result gt allowable
    level RP

23
Michigan Regulation of WET/Recent Changes
  • Reasonable Potential
  • WET Limit not a death sentence
  • WET testing is expensive
  • Monitoring frequency reduction reduces costs
  • Lobby for this is in NPDES permit
  • RP will be recalculated at next permit cycle

24
Michigan Regulation of WET/Recent Changes
  • Promulgated WET methods now required
  • Daphnia magna chronic method unavailable (not
    promulgated)
  • Promulgated methods include

25
Michigan Regulation of WET/Recent Changes
  • Acute methods (survival)
  • Fathead minnow
  • Trouts
  • Daphnids

Courtesy of Indiana University
26
Michigan Regulation of WET/Recent Changes
  • Chronic Methods
  • Fathead minnow
  • Survival
  • Growth
  • Ceriodaphnia dubia
  • Survival
  • Reproduction

27
Michigan Regulation of WET/Recent Changes
  • Alpha 0.01 (ca. 2000)
  • Used for most controversial/sensitive endpoints
  • Ceriodaphnia dubia reproduction
  • Fathead minnow growth
  • Raises the bar for finding toxicity by reducing
    the statistical chance of a false positive
  • Objective use valid data for WET regulation

28
Michigan Regulation of WET/Recent Changes
  • NPDES Permit Application now requires WET data
    (1999)
  • WWTP with
  • gt 1 MGD design flow
  • Or
  • Federal IPP/Requirement to develop Federal IPP
  • Implemented in Michigan NPDES permits

29
Michigan Regulation of WET
  • What youll see in NPDES Permits
  • Nothing
  • Annual WET monitoring (permit app requirement)
  • WET Monitoring
  • WET Limit (RP)
  • Toxicity Reduction Evaluation (TRE)
  • WET consultant generally required, especially for
    TRE work

30
Maximizing Effect/Minimizing Cost/WET Consultants
  • WET Consultant choice
  • Shop around
  • Ask your peers
  • Price isnt everything data quality is essential

31
Maximizing Effect/Minimizing Cost/WET Consultants
  • WET consultant recommendations
  • Contract who pays if test QA/QC fails?
  • Chronic tests Does consultant use Alpha 0.01 for
    statistical analyses?
  • How does consultant address
  • ammonia toxicity exaggeration
  • pathogen interference

32
Maximizing Effect/Minimizing Cost/WET Consultants
  • MDEQ data quality review
  • Consultants arent always right
  • Ammonia toxicity exaggeration
  • Unexplainable concentration-response
  • Pathogen interference
  • QA/QC problems
  • Ask me, anytime. MDEQ wants to use only valid
    WET data

33
Maximizing Effect/Minimizing Cost/WET Consultants
  • Consultants may help with Reasonable Potential
    (RP) concerns
  • If toxicity is detected, ask consultant if RP
    will be indicated
  • Or, you may ask me

34
Maximizing Effect/Minimizing Cost/WET Consultants
  • Does consultant contact MDEQ if there are WET
    test data quality concerns?

35
Maximizing Effect/Minimizing Cost What you Can Do
  • Ensure Data Validity
  • Sample during representative operations
  • But dont game sampling to avoid toxicity

36
Maximizing Effect/Minimizing Cost What you Can Do
  • Use clean sampling equipment/avoid sample
    contamination
  • Ice samples well
  • If ammonia is present in sample, inform WET
    consultant
  • Test design can be modified to reduce ammonia
    toxicity exaggeration

37
Maximizing Effect/Minimizing Cost What you Can Do
  • When toxicity is detected
  • Ensure result is representative
  • Review facility operations
  • Unusual operations or occurrences

38
Maximizing Effect/Minimizing Cost What you Can Do
  • When toxicity is detected
  • Investigate toxicity
  • Contact non-domestic users
  • New water treatment additive?

39
Maximizing Effect/Minimizing Cost What you Can Do
  • When toxicity is detected
  • Ask consultant what can be done
  • To investigate toxicity
  • Effect on next NPDES permit
  • And/or ask my office what can be done

40
MDEQ Aquatic Toxicology Laboratory
  • Lansing
  • Bill Dimond, Aquatic Biology Specialist
  • Diana Butler, Laboratory Technician
  • Contact (Bill)
  • 517-327-2622
  • dimondw_at_michigan.gov
  • Please call or email me anytime
Write a Comment
User Comments (0)
About PowerShow.com