Developing Chemical-Specific Water Quality-Based Effluent Limits - US EPA
WQBELs-Part IV
Calculate Chemical-specific WQBELs and Final Limits
Establishing Water Quality-based Effluent Limitations in NPDES Permits:
Part IV--Calculate Chemical-specific WQBELs and Determine Final Effluent Limitations
Today's Speakers
David Hair Environmental Engineer US Environmental Protection Agency Washington, DC
Greg Currey Environmental Engineer Tetra Tech, Incorporated Fairfax, Virginia
WQBELs Part IV-2
NPDES Web-based Training
WQBELs Part IV-1
WQBELs-Part IV
Calculate Chemical-specific WQBELs and Final Limits
Establishing WQBELs in NPDES Permits
Part I: Identify Applicable Water Quality Standards
Part II: Characterize the Effluent and Receiving Water Part III: Determine the Need for WQBELs
Part IV: Calculate Chemical-specific WQBELs and Determine Final Limitations
WQBELs Part IV-3
Part I Review: Relationship Between WQS and Effluent Limitations
Recall from Part I (Identify Applicable WQS):
? Water quality standards apply throughout the waterbody (or segment of a waterbody) as defined by the state, territory, or tribe
? Effluent limitations apply at the compliance point established in the permit (generally "end of pipe")
WQBELs Part IV-4
NPDES Web-based Training
WQBELs Part IV-2
WQBELs-Part IV
Calculate Chemical-specific WQBELs and Final Limits
Part I Review: WQS Implementation Procedures
Water quality standards and their implementing procedures (including NPDES requirements) specify methods for determining the need for WQBELs and for calculating WQBELs that ensure that standards are attained.
Where can these methods be found? ? EPA's Technical Support Document ? state regulations ? state water quality management plans ? state guidance ? past practices ? We never thought about this before!
WQBELs Part IV-5
Part II Review: Step 1--Identify Pollutants of Concern
Recall from Part II (Characterize Effluent and Receiving Water) that pollutants of concern are pollutants:
? With an applicable technology-based effluent limitation (TBEL)
? With a wasteload allocation (WLA) from a total maximum daily load (TMDL)
? Identified as needing WQBELs in the previous permit
? Identified as present in the effluent through monitoring
? Otherwise expected to be present in the discharge
WQBELs Part IV-6
NPDES Web-based Training
WQBELs Part IV-3
WQBELs-Part IV
Calculate Chemical-specific WQBELs and Final Limits
Part II Review: Step 2--Determine the Allowable Dilution or Mixing Zone in the Receiving Water
Also recall from Part II (Characterize Effluent and Receiving Water) that we need to:
Determine whether water quality standards permit dilution allowances or mixing zones
Determine critical conditions (e.g., critical stream flow)
Determine type of mixing under critical conditions
? Rapid and complete mixing ? Incomplete mixing
Determine dilution allowance or regulatory mixing zone size for calculations
WQBELs Part IV-7
Part III Review: Is There Reasonable Potential?
Effluent and Receiving Water Characteristics
(Part II)
Water Quality Model (Steady-state or Dynamic)
Receiving Water Concentration
Limitations must be established in permits to control all pollutants or pollutant parameters that are or may be discharged at a level that will cause, have reasonable potential to cause, or contribute to an excursion above any state water quality standard [40 CFR 122.44(d)(1)(i)].
WQBELs Part IV-8
NPDES Web-based Training
WQBELs Part IV-4
WQBELs-Part IV
Calculate Chemical-specific WQBELs and Final Limits
Developing Chemical-specific WQBELs
Water Quality Criteria ? Magnitude ? Duration ? Frequency
Effluent Limitations ? Magnitude ? Averaging Period
Permit writers calculate end-of-pipe water quality-based effluent limitations where necessary to ensure that water quality standards are attained in the receiving water.
1W-9QBELs Part IV-9
Part IV: Steps in Developing Chemical-Specific WQBELs from Aquatic Life Criteria
Step 1: Determine Acute and Chronic Wasteload Allocations (WLAs) from Aquatic Life Water Quality Criteria
Step 2: Calculate Long-Term Average (LTA) for Each WLA
Step 3: Select Lowest LTA
Step 4: Calculate Maximum Daily Limit (MDL) and Average Monthly Limit (AML)*
*Other averaging periods used where appropriate (e.g., instantaneous maximum and instantaneous minimum for pH)
WQBELs Part IV-10
NPDES Web-based Training
WQBELs Part IV-5
................
................
In order to avoid copyright disputes, this page is only a partial summary.
To fulfill the demand for quickly locating and searching documents.
It is intelligent file search solution for home and business.
Related download
- estimation of queue lengths and their percentiles at signalized
- appendix 8 worksheet calculating pro rated assistance for mixed
- equations for calculating exposure management objectives
- a pocket guide to blood pressure measurement in children
- calculating peq determining a discharger s effluent quality ohio
- using your ti nspire calculator normal distributions
- using the bmi for age growth charts centers for disease control and
- different ways of calculating percentiles using sas
- calculating 95 upper confidence level ucl ohio
- calculating upper confidence limits for exposure point concentrations
Related searches
- water quality activities for kids
- water quality education for kids
- water quality education material
- water quality issues
- water quality issues in us
- water quality activity
- water quality games for kids
- drinking water quality issues
- tap water quality by state
- epa water quality reports
- us water quality by state
- epa local water quality report