320 likes | 451 Views
West Virginia Department of Environmental Protection. Draft TMDL Public Meetings April 21, 2014. West Fork River Watershed TMDLs. TMDL/ water quality standards recap Overview of this TMDL effort Explanation/demonstration of electronic documents, spreadsheets, tools
E N D
West Virginia Department of Environmental Protection Draft TMDL Public Meetings April 21, 2014 West Fork River Watershed TMDLs
TMDL/ water quality standards recap • Overview of this TMDL effort • Explanation/demonstration of electronic documents, spreadsheets, tools • Questions and Answers Agenda
“Total Maximum Daily Load” • How much pollutant a stream can receive and remain healthy • A Pollution Budget – prescribes reduction of pollutants (where needed) that result in the restoration of an impaired stream • TMDL development is required by the Clean Water Act for all streams impaired by a pollutant What’s a TMDL?
Stream that doesn’t meet water quality standards • WV Water Quality Standards are codified in 47CSR2 • ttp://apps.sos.wv.gov/adlaw/csr/ruleview.aspx?document=8208 • Standards include “Designated Uses” for WV waters and the criteria to protect those uses • Water Quality Criteria can be numeric or narrative What’s an Impaired Stream?
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 • 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
Additional Criteria of Concern • Dissolved Aluminum • Aquatic Life • Not to exceed 750 ug/l as a 1 hour average concentration more than once in a three year period • Not to exceed 750 ug/l (warmwater) as a 4 day average concentration more than once in a three year period • pH • Aquatic Life/Water Contact Recreation/Public Water Supply • No values below 6.0 nor above 9.0.
Additional criteria of concern(Bingamon Run & tribs) • Chloride • Aquatic Life/Water Contact Recreation/Public Water Supply • Not to exceed 230 mg/l as a 4 day average concentration more than once in a three year period
Based on Benthic Macroinvertebrates West Virginia Stream Condition Index (WVSCI) Standardized method for assessing benthic macroinvertebrates (aquatic bugs) WVSCI stream scores normalized to 0 - 100 range Streams scoring less than the 60.6 threshold value labeled as “impaired” and placed on the 303(d) list Streams listed as impaired slated for TMDLs “Biologically Impaired” streams evaluated for source/s of impairment during the TMDL development process (Stressor Identification Process) Narrative CriteriaPrevious 47 CSR 2 - 3.2.i Assessment
Senate Bill 562 passed by the 2012 West Virginia Legislature amended the WV Water Pollution Control Act • Requires “evaluation of the holistic health of the aquatic ecosystem” • 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 Narrative Criteria2012 Legislative Changes
Method to evaluate stressor/s of biologically impacted streams • Process used to evaluate if numeric TMDLs (iron, fecal) will address biological stressors • Information will be retained and may be used to delist streams in the future (see Table 4.1) Stressor Identification Process
S = “sum of” • WLA = “wasteload allocations” • LA = “load allocations” • MOS = “margin of safety” • WLAs - pollutant loads for “point sources” • Discharge from point • Need NPDES permit • LAs - pollutant loads for “nonpoint sources” and background • Precipitation and runoff • No permit required TMDL = S WLA + S LA + MOS
Project Timeline: • Proposed streams advertised for public comment April 2010 • Initial Public Meetings (TMDL Intro) July 2010 • Watershed Monitoring and Source Tracking July 2010 - June 2011 • Draft TMDL Public Meeting Today TMDL Development History
Impaired Waters 305 named streams – See Table 3-3 beginning on page 11 of Draft Report for a complete list of streams and impairments
MDAS (Mining Data Analysis System) • Fecal Coliform, iron, chlorides, Al and pH • Can handle point and nonpoint sources (representation and allocation) • Recognizes exposure duration and exceedence frequency components of criteria Modeling
Modeling • 52 TMDL watersheds • 700 subwatersheds • West Fork mainstem is included
Design precipitation period Hourly precipitation data for a six-year period Design period includes wet and dry years Applied to present day land uses Permitted discharges equal to permit limits Baseline Condition
Existing pollutant sources reduced such that TMDL endpoints are achieved in each modeled subwatershed recognizing • Criteria value, duration and exceedence frequency • Margin of safety TMDL Condition
Required component of TMDLs • Explicit 5% used in most TMDLs • TMDL endpoints for numeric criteria are 95% of criterion value (ex.1.425 mg/l for 1.5 mg/l criterion) Margin of Safety
Streambank erosion Abandoned Mine Lands Upland Sediment Sources Harvested Forest Oil and Gas Agriculture Urban Residential Stormwater Roads Active Mining Construction Stormwater General Permits Pollutant Sources (Iron)
Streambank Erosion reduced to reference stream loadings • Sediment sources, including AML, set to iron loadings equivalent to 100 mg/l TSS • AML seeps set to WQ at end of pipe • Mining point sources set to WQ at end of pipe where needed for modeled attainment Iron Reduction Strategy
Future growth for Construction Stormwater throughout the impaired watershed drainage was initially allocated at 2.5% of subwatershed area • If further reductions needed then based on sensitivity analysis: • CSGP areas were reduced incrementally from 2.5 to 0.5 % and/or • Dominant land sources were reduced incrementally below 100 TSS threshold until endpoint is met or 70 mg/l TSS • If further reductions needed at subwatershed pour points then CSGP areas were reduced to 0% • Nonpoint source reductions did not result in LA lower than background concentrations • Point Source reductions did not result in WLA more stringent than water quality standards end of pipe Iron Reduction Strategy continued
Significant Dissolved Aluminum/pH sources: • Abandoned Mine Land seeps • Atmospheric Acid Deposition • Active mining sources and sediment associated aluminum sources were also represented in the model but no reduction was required Modeled Aluminum Sources
All pH/Dissolved Aluminum impaired streams are also impaired for iron • First step is reduction of total iron sources (e.g. seeps) to meet iron TMDL endpoints since instream dissolved iron concentrations can reduce pH levels and affect instream dissolved aluminum levels • Alkalinity was added to achieve target pH of approximately 6.5 at all subwatershedpourpoints. • If further reductions were needed, total aluminum reductions and/or further alkalinity additions were made until Al(d) and pH TMDL endpoints were met Dissolved Aluminum/pH Reduction Strategy
Fecal Coliform • STP effluents represented at existing limits (200/400) • Failing/nonexistent on-site sewage systems – 100% reduction • Combined Sewer Overflows (CSOs) - reduced to water quality criteria (200/400 cts) • Sensitivity Analysis based reductions • Urban runoff • Agriculture Fecal Pollutant Sources & Strategy
Source allocations developed for all subwatersheds contributing to chloride impaired streams • Individual WLAs were developed for all high volume, pumped discharge, mining outlets (discharges dominated stream flow) • Individual WLA based on chronic aquatic life protection criterion (230 mg/l) • Non appreciable chloride contributions from all other sources are contained in aggregated loads for Background & other Nonpoint sources Chloride Sources and Reduction Strategy
New facility anywhere in watershed if meeting water quality criteria end of pipe • Subwatershed-specific future growth allowances have been provided, where possible, for site registrations under the Construction Stormwater General Permit • Full details on Future Growth can be found beginning on page 86 of the Draft report Future Growth Highlights
Public Comment period ends May6, 2014 • Documents may be reviewed/downloaded from DEP webpage http://www.dep.wv.gov/WWE/watershed/TMDL/Pages/default.aspx • CD available upon request – CD includes GIS Shapefiles and Technical Report • Comments should be submitted to Steve Young at Stephen.A.Young@wv.gov • Questions - contact Dave Montali, Jim Laine • (304) 926-0499 (Ext 1063, 1061,) • David.A.Montali@wv.gov • James.C.Laine@wv.gov Public Comment
TMDL Products • Main Report – Overall description of the TMDL development process for the West Fork River watershed • Technical Report with detailed appendices
TMDL Products • Allocation spreadsheets: • Fecal Coliform, Iron, Dis. Al, pH, Chlorides • TMDL for each stream, WLAs and LAs by SWS • Filterable • GIS shapefiles, along with Technical Report and Appendices, available on CD