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This update provides an overview of the Total Maximum Daily Load (TMDL) project in the Tygart Valley Watershed. It covers the allocation strategies, impaired streams, and the modeling approach used.
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West Virginia Department of Environmental Protection Tygart Valley Watershed TMDL Status Update May 18 & 19, 2015
Agenda • “Introduction to TMDLs” recap • Overview of TMDL Project & 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 • Pollution Budget - prescribes reductions (where needed) of pollutants that result in the restoration of an impaired stream • TMDL development required by Clean Water Act for streams impaired by a pollutant
TMDL = S WLA + S LA + MOS • S = “sum of” • WLA = “wasteloadallocations” • LA = “load allocations” • MOS = “margin of safety” • WLAs - pollutant loads from “point sources” • Discharge from point • Need NPDES permit • LAs - pollutant loads from “nonpoint sources” and background • Precipitation/runoff driven • No permit required
What’s an impaired stream? • Stream that doesn’t meet water quality standards • West Virginia Water Quality Standards are codified in 47 CSR 2 • http://www.dep.wv.gov/WWE/Programs/wqs/Documents/Rule%20Approved%20Letter%20and%20Rule%20Itself%202014/WVDEP_WQS_2014Tri-Review_FinalRule47CSR2_June_2014.pdf • Standards include “Designated Uses“ for WV waters and “water quality criteria” to protect those uses • Criteria can be numeric or narrative • Impaired streams are enumerated on the 303(d) list
West Virginia Section 303(d) List / Integrated Report
Numeric Criteria of Concern • Total Iron • Aquatic Life/Public Water Supply • Not to exceed 1.5 mg/l as a 4 day average concentration more than once in a three year period (warmwater) • Not to exceed 1.0 mg/l as a 4 day average concentration more than once in a three year period (troutwater) • Public Water Supply - 1.5 mg/l • Fecal Coliform • Water Contact Recreation/Public Water Supply • Shall not exceed 200 counts/100ml as a monthly geometric mean (5 samples/month) • Nor to exceed 400 counts/100 ml in more than 10% of samples in a month
Numeric Criteria of Concern • Dissolved Aluminum • Aquatic Life • Not to exceed 750 ug/l as a 1 hour or 4 day average concentration more than once in a three years (warmwater) • Not to exceed 750 ug/l as a 1 hour average or 87 ug/l as a 4 day average concentration more than one in three years (troutwater) • pH • Aquatic Life/Water Contact Recreation/Public Water Supply (All Uses) • No values below 6.0 nor above 9.0.
Numeric Criteria of Concern • Beryllium • Aquatic Life/Public Water Supply • Not to exceed 130 ug/l as a 1 hour average concentration more than once in a three year period • Not to exceed 4 ug/l (Drinking water) • Birds Creek, Squires Creek, Left Fk/Little Sandy, Cassity Fork • Total Manganese • Public Water Supply • Not to exceed 1.0 mg/l within a 5 mile zone immediately upstream of a water supply used for public or private consumption
Numeric Criteria of Concern • Dissolved Oxygen • Aquatic Life/Public Water Supply/Contact Recreation • Not less than 5.0 mg/l at any time • Not less than 7.0 in spawning area and in no case less than 6.0 at any time (trout)
Based on Benthic Macroinvertebrates (aquatic bugs) Stream scored based on abundance and type of bugs present Streams with impaired communities were placed on the 303(d) list and slated for TMDLs Narrative CriteriaPrevious 47 CSR 2 - 3.2.i Assessment
Narrative Criteria2012 Legislative Changes • Senate Bill 562 passed by the 2012 West Virginia Legislature amended the WV Water Pollution Control Act • Requires DEP to develop and secure legislative approval of new rules to interpret 47 CSR 2-3.2.i • Section 22-11-7b : http://www.legis.state.wv.us/wvcode/ChapterEntire.cfm?chap=22&art=11 • No biological TMDLs are part of this effort • Streams currently listed as biologically impacted will undergo Stressor Identification process
Stressor Identification Process • Method to evaluate stressor/s of biologically impacted streams • Process used to evaluate if numeric criteria TMDLs (iron, fecal) will address biological stressors • Information will be retained and may be used to delist streams in the future
Tygart River Basin including mainstem • 84 TMDL Watersheds
Tygart River Basin • 336 sample sites on 227 streams • 520 Subwatersheds • MDAS model
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
Modeling Approach • Segment watershed • Configure model to represent all sources • Calibrate model for hydrology (flow) and water quality • Metals • Iron Dis. Aluminum Manganese Beryllium • pH • Fecal • Dissolved Oxygen • Sediment • Run MDAS for Baseline conditions (existing) • Run MDAS for TMDL scenario(s)
Completed: Monitoring Source tracking Baseline Modeling Bio. Stressor Ids Status Update Meeting Next Steps: Allocations Draft Document Public Meeting EPA Approval Tygart Valley River WatershedProject Status
Allocation Methodology • Universal Reduction of targeted sources • Streambank erosion, Failing Septics, etc • 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 in general • Critical conditions must be considered • Sometimes only one significant source in sws • Always some amount of professional judgement
Fecal Coliform/Dissolved Oxygen Sources • Point sources • HAUs • Package Plants • Combined Sewer Overflows • Municipal Sewage Plant • Mining Bathouses • MS4 areas • Nonpoint source • Failing septic systems and/or straight pipe illicit discharges • Stormwater runoff from urban/residential lands • Stormwater runoff from agricultural lands
Fecal Coliform/Dissolved Oxygen Strategy • 100% reduction of all untreated sewage discharges (failing septics, straight pipes) as required by WV Bureau for Public Health regulations • Sensitivity analysis to address severity of agricultural vs. urban/residential impacts • Assess impacts to D.O. from organic enrichment reductions required by fecal TMDLs
Streambank erosion Abandoned Mine Lands and seeps Bond Forfeitures Lands and seeps Upland Sediment Sources Harvested Forest Oil and Gas Agriculture Urban Residential outside MS4 areas Roads Active Mining MS4 areas Construction Stormwater General Permits Iron Sources
Iron Allocation Strategy • Streambank erosion loadings reduced to best available in watershed • Sediment sources set to iron loadings equivalent to 100 mg/l TSS • Future growth for Construction Stormwater area initially allocated at 2.5% of subwatershed area • AML seeps set to WQ criteria at discharge
Iron Allocation Strategy continued • Sensitivity Analysis based reductions, if needed • mining permits / bond fortfeiture reduced below baseline • sediment sources reduced below 100 mg/l TSS • Construction stormwatergrowth allowance reduced
Dissolved Aluminum/pH Sources & Strategy • Sources • AML • Bond Forfeiture • Active Mining • Strategy • Evaluate effects on pH and Al(d) of any concurrent iron TMDLs being developed • Add alkalinity to counter acid effects of AML seeps, and evaluate Al(d) attainment • Sensitivity – increase alkalinity and/or reduce aluminum to attain both pH and Al(d) criteria
Beryllium • New impairment for TMDL process • Initial data review seems to indicate Be impairments correlated with low pH discharges (<5.0 s.u.) • Currently evaluating additional instream chemistry processes • Additional information will be available for draft TMDL meeting this fall
Manganese Sources & Strategy • Tenmile Creek is impaired for manganese based on proximity to drinking water intake • Sources • Active Mining • AML • Strategy • AML seeps reduced to water quality standards end of pipe • Permitted outfalls currently at water quality standards end of pipe
WVDEP TMDL Process (4 yrs) • Stream Selection - (4/2012) • Pre-TMDL monitoring, source identification and characterization - (7/2012 – 6/2013) • Contract to model water quality and hydrology – (1/2014) • Determine baseline condition and allocate pollutant loads • Draft Report development • Finalization and EPA approval
Tygart Valley River Watershed TMDL Path Forward • Allocate loads and wasteloads and develop draft report • Formal public comment period and public meeting on the draft TMDLs in Fall 2015 • 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, Mike McDaniel • (304) 926-0499 • David.A.Montali@wv.gov, James.C.Laine@wv.gov, or Michael.L.McDaniel@wv.gov