James Nusrala

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Oregon Municipal Permitting IssuesACWA Workshop
December 1, 2005
Reasonable Potential Analysis for Toxic
Pollutants Internal Management Directive
James Nusrala Marty Fitzpatrick Oregon
Department of Environmental Quality, Water
Quality Division
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Overview

• Topics covered
• Why, How, and Whos Affected
• The Process
• Implications of IMD
• Q A

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Topics Covered in RPA IMD

• Information Gathering
• NPDES Application Review
• Antidegradation
• Receiving Water/Effluent Characterization
• Calculations
• RPA/Limits for Toxic Pollutants
• Whole Effluent Toxicity
• Documentation

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Toxics RPA IMD Why How

• Revised Toxics rules (incl. criteria) May 2004
• RPA IMD development
• Drafts (internal/external review)
• Training
• Authorization in September 2005

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Which Point Sources are Affected

• Domestic Facilities
• Average Dry Weather Design Flow gt 1 million
  gallons per day (MGD) All toxic pollutants
• Design flow greater than 0.1 MGD, but less than 1
  MGD Chlorine and Ammonia

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Which Point Sources are Affected

• Industrial Facilities with Toxic Monitoring
  Requirements
• Primary Industries Metals required for all,
  organic fractions by industrial category
• Secondary Industries At discretion of permit
  writer, considering potential for toxic impacts
  to receiving water

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Two Questions Being Asked of Point Sources

• When will a limit be needed for a toxic
  pollutant? (when will there be reasonable
  potential?)
• If a limit is needed, what should that limit be?

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Key Features

• Reasonable Potential Analysis for Toxics-Numeric
  Criteria
• Calculating Effluent Limitations for Toxics
  Numeric Criteria
• Whole Effluent Toxicity

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• Reasonable Potential Analysis

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Effluent Characterization- Ch.5

• RPA Methodology ? 1991 U.S. EPA TSD
• Minimum data requirements
• Effluent toxics data
• Background toxics data
• Dilution information

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Data Requirements - Domestics
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Permit Renewal Application Meet Minimum
Requirements?

• If sufficient data
• Conduct RPA
• If insufficient data
• Reject application, or
• Reissue permit, with a compliance schedule for
  monitoring and re-opener clause to perform RPA

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• Effluent Limit Calculation

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Limit Development Ch. 6

• WQBEL methodology ? 1991 EPA TSD
• Decision matrix ? most stringent limit
• Compliance schedule provision

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• Whole Effluent Toxicity

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Whole Effluent Toxicity Characterization Ch. 7

• Who? All domestic sources with a dry weather
  design flow gt 1 MGD
• How Much? Minimum of 4 WET tests of 3 species
  for both acute and chronic endpoints 10
  Recommended for larger sources

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Whole Effluent Toxicity Evaluation

• Insufficient data? Reissue permit with
  compliance schedule
• Sufficient data?
• IF WET test no toxicity no limits, yearly
  monitoring
• If WET test toxicity increased frequency of
  testing, possible Toxicity Identification/Reductio
  n Evaluation

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Implications Increased Monitoring

• Required to adequately characterize
  effluent/receiving water environment
• Costs spread throughout life of permit
• Frequency decreases if non-detect
• Advance notice will be given for planning/budget
  allocation

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Implications Potential for Additional Effluent
Limits

• Toxic pollutant limits if reasonable potential to
  exceed instream toxics criteria
• Interim limits/compliance schedules a possibility
  
• Need to re-evaluate pretreatment local limits
  with lower criteria

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Anticipated Means to Comply

• Implement strengthened pretreatment local limits
• Proactive industrial waste surveys
• Invigorated pollution prevention outreach and
  education
• Improved capability of detection limits

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For More Information

• Location of Toxics RPA IMD www.deq.state.or.us/w
  q/wqpermit/wqpolicies.htm
• Contact Information
• James Nusrala
• DEQ Water Quality Division
• [phone]
• Nusrala.james_at_deq.state.or.us
• Martin Fitzpatrick
• DEQ Water Quality Division
• [phone]
• Fitzpatrick.martin_at_deq.state.or.us