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West Virginia Department of Environmental Protection. Middle Ohio South Watershed TMDL Status Update Meeting. August 31, 2011 Ravenswood High School. Agenda. “Introduction to TMDLs” recap Overview of Middle Ohio South Watershed Project and Status Overview of Allocation Strategies
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West Virginia Department of Environmental Protection Middle Ohio South Watershed TMDL Status Update Meeting August 31, 2011 Ravenswood High School
Agenda • “Introduction to TMDLs” recap • Overview of Middle Ohio South Watershed Project and Status • Overview of Allocation Strategies • Discussion – Free form questions and answers
What’s a TMDL? • “Total Maximum Daily Load” • How much pollutant a stream can receive and remain healthy • TMDL is a pollution budget – prescribes reduction of pollutants that result in the restoration of an impaired stream • TMDL development required by Clean Water Act for all impaired streams
What’s an impaired stream? • Stream that doesn’t meet water quality standards • West Virginia Water Quality Standards are codified in 47 CSR 2 • Standards include designated uses for WV waters and water quality criteria to protect those uses • Criteria can be numeric (concentration less than certain number) or narrative (nothing in toxic amounts to man or aquatic life) • Impaired streams are on the 303(d) List
West Virginia Section 303(d) List / Integrated Report
Numeric Criteria Examples Iron • Warmwater Aquatic Life use - 4-day average concentration not to exceed 1.5 mg/l more than once every three years Fecal coliform • Not to exceed 400/100ml (10% monthly samples) • Nor greater than 200/100 ml geometric mean (5/month)
Narrative Criterion • Biological Impairment • Conditions Not Allowable in State Waters • (47 CSR 2-3.2i) “.....no significant adverse impact to the chemical, physical, hydrologic or biological components of aquatic ecosystems shall be allowed.”
Biological Impairment • WV Stream Condition Index (WVSCI) • Standardized sample collection and analysis methodology for aquatic bugs • Multimetric – multiple types of information are evaluated • Rating Scale – 0 to 100
Biological Impairment • Streams with WVSCI scores < 60.6 are considered biologically impaired • Biological impairment TMDL –development process includes a “Stressor ID” preliminary step to identify the pollutant(s) causing the impairment • TMDL then developed for causative stressor
Stressor – TMDL Link • Organic Enrichment – Fecal Coliform surrogate • Sedimentation – Total Iron surrogate
Middle Ohio South Watershed Impairments • Approximately 88 impaired streams (monitoring) • Approximately 200 impairments - Fecal Coliform, Total Iron, Biological Integrity • Does not include mainstem Ohio River
TMDL Components TMDL =WLA +LA+MOS • Pollutant allocations to point sources are called wasteload allocations (WLA) • Pollutant allocations to nonpoint sources are called load allocations (LA) • TMDLs must include a margin of safety (MOS); Explicit 5% MOS is used
WVDEP TMDL Process (4 yrs) • Stream Selection • Pre-TMDL monitoring, source identification and characterization • Contract to model water quality and hydrology • Determine baseline condition and allocate pollutant loads • Report development • Finalization and EPA approval
MDAS Model • Watershed Model • Runs dynamically on a 1-hour time step • Represents land use (hydrologic processes) and river processes • Can include nonpoint and point sources • Streambank Erosion component - Bank Pin Study
Bank Erosion Pin Study • December 2009-March 2011, ongoing • 87 total sites with 4-10 pins/site • 5 measurements/site • Total Erosion rate: 0 - ~300 mm (11.8 in) • Most erosion occurs after freeze-thaw cycle (barren banks) • Correlate erosion rate with bank conditions & land use.
Modeling Approach • Segment watershed • Configure model to represent all sources • Calibrate model for hydrology (flow) and water quality • Iron • Fecal • Sediment • Run MDAS for Baseline conditions (existing) • Run MDAS for TMDL scenario(s)
Middle Ohio South Watershed Approximately 88 impaired streams Approximately 200 impairments 486 subwatersheds delineated where model makes water quality predictions Project does not include mainstem Ohio River
Completed: Monitoring Source tracking Baseline Modeling (ongoing) Bio. Stressor Ids Status Update Meeting Next Steps: Allocations Draft Document Public Meeting EPA Approval Middle Ohio South Project Status
Allocation Methodology • Top-down approach • Headwater subwatersheds analyzed first • Allocation strategy dictates order and magnitude of reduction • If necessary, loads are reduced then routed to downstream subwatershed
Allocation Methodology • WVDEP priorities: • Ensure criteria compliance at all sws outlets • Target the primary causative sources • Strategy is general • Sometimes only one significant source in sws • Critical conditions must be considered • Always some amount of professional judgement
Fecal Coliform Sources • Point sources • Municipal Facilities (WWTP) • Package Plants • Home Aeration Units • CSO (Combined Sewer Overflow) • MS4 entities including DOH (Municipal Separate Stormwater Sewer Systems) • Nonpoint source • Failing septic systems and/or straight pipe illicit discharges • Stormwater runoff from Non MS4 urban/residential lands • Stormwater runoff from agricultural lands
Fecal Coliform Strategy • 100% reduction of all untreated sewage discharges (failing septics, straight pipes) as required by WV Bureau for Public Health regulations • Reduction of CSO sources to criterion value • Reduction of MS4s to criterion values • Sensitivity analysis to address severity of agricultural vs. urban/residential impacts
Metals (Fe) Sources • Point sources • Discharges from active mining operations • Non-mining industrial discharges • Construction Stormwater • MS4 discharges • Nonpoint sources • Abandoned Mine Lands • Bond forfeiture sites • Sediment sources (forestry, oil and gas, roads, agriculture, non MS4 urban/residential, streambank erosion)
Total Iron Strategy • Reduction of AML to practical limits (undisturbed forest loading for surface disturbances; water quality criteria values for seeps • If metals are strongly associated with TSS, reduction order is AML, sediment sources including MS4 entities, then active mining permits and bond forfeiture sites • If no metals/TSS correlation, proposed order is AML, bond forfeiture sites and active mining permits
Middle Ohio South WatershedTMDL Path Forward • DEP/Tetra Tech will allocate loads and wasteloads and develop draft report • Formal public comment period and public meeting on the draft TMDLs in first quarter of 2012 • DEP will address comments, prepare final draft and submit to EPA for approval (final draft will include Response Summary)
Contact Information • Comments should be submitted to Steve Young at Stephen.A.Young@wv.gov(10 meg limit for email) • Questions - contact Dave Montali, Jim Laine, Ben Lowman, Mike McDaniel • (304) 926-0499 • David.A.Montali@wv.gov, James.C.Laine@wv.gov, Benjamin.M.Lowman@wv.gov, or • Michael.L.McDaniel@wv.gov