October 18 th , 2016 CDPHE - C1E, 1-3pm Time Agenda Topic Lead - PowerPoint PPT Presentation

October 18 th , 2016 CDPHE - C1E, 1-3pm

Time Agenda Topic Lead 1:00pm Introductions/review agenda Sarah Wheeler Assessment of Fe, Mn and SO4 Skip Feeney, Christine 1:10pm Water Supply Standards Johnston, Karl Hermann 2:00pm Break Assessment of data collected Arne Sjodin, 2:10pm after a fire, flood or other Scott Garncarz catastrophic events 3:00pm Adjourn

Topics 1. Background – What problem are we solving? 2. Subgroup involvement 3. Point source evaluation 4. Non-point source evaluation 5. Insufficient data from the year 2000 and increased discharges 6. Overall flow chart 7. Listing Methodology language change

Background The least restrictive of the following two options apply: 1. Existing quality as of January 1, 2000; or 2. Table value criteria Iron 300 ug/l (dissolved) – – Manganese 50 ug/l (dissolved) Sulfate 250 mg/l – The commission essentially grandfathered in existing levels of these constituents Regulation 31.11(6)

Background Issue - Insufficient data to determine existing quality as of the year 2000 Provision - Data generated subsequent to January 1, 2000 shall be presumed to be representative of existing quality as of January 1, 2000, if the available information indicates that there have been no new or increased sources of these pollutants impacting the segment(s) in question subsequent to that date.

Subgroup Karl Herman Christine Johnston Sarah Wheeler Skip Feeney Goals: New or increased pollutant evaluation criteria and process -Point Source -Non-point Sources

Existing Quality as of 2000 – Data from 1995-2009 – Compiled by segment – 85 th percentile of iron and manganese and 50 th percentile of sulfate – If <10 samples exist from 1995-1999, time period is extended in 5 year increments – Data collected after the year 2000 can be used if no new or increased sources exist

Investigation of point sources Task – Determine if there are no new or increased sources of dissolved iron, dissolved manganese and sulfate impacting the segment of interest. – Permits with iron, manganese and sulfate monitoring requirements • New facility (after 2000) = new source • Existing facility (before 2000) = evaluate change in discharge – Short term permits excluded – Located on or 5 miles upstream of segment

Investigation of point sources • DMR data from existing facilities – 45,000 result records from ICIS, but newer than 2005. – Consider other sources, if readily available, of discharge monitoring reports – • Hard copies, scanned copies, discharger provided materials.

Flow Chart Review Refer To Handouts

Investigation of non-point sources Task – Identify new or increased non-point sources of dissolved iron, dissolved manganese and sulfate impacting the segment of interest.

Investigation of non-point sources Question – Can land use be used as a predictor of new or increased non-point sources of dissolved iron, dissolved manganese and sulfate in a watershed? Answer – We don’t yet know that changes in land use cause increases in these parameters

Investigation of non-point sources Conclusion: • Focus on point sources • Continue to research link between land use and Fe, Mn, SO4

Insufficient Data and New Sources Segment Exceeds TVS (n≥10) 2016 303(d) Listing • Methodology – cases with insufficient 2000 data and New or Sufficient NO increased new sources identified = data from source(s) 2000 M&E list, until more data since (n≥10) ? 2000? can be collected M&E LIST

Insufficient Data and New Sources Segment Exceeds TVS (n≥10) • Problem – can’t go back in time • Intent of standard was to New or Sufficient NO increased utilize TVS data from source(s) 2000 since (n≥10) ? 2000? • 2018 303(d) LM – proposing to use 303(d) List where new or increased sources have Use TVS – 303(d) List been identified

Flow Chart Review Refer To Handouts

Draft Language Review Refer To Handouts

Next Steps December 8, 2016 • Existing Quality as of 2000 Data Library • Final modifications / thoughts on LM language

Segment • Point source within 5 mile upstream Starts buffer. WWTF • Original permit issue date 1995. • Current instream data collected from 2012 to 2013. Mn = 151ug/L, n=15 • DMR data from 2009-2016 available. • Manganese not monitored

Background: • 2016 303(d) List – Waldo Canyon Fire (Fountain Creek and tribs) – Post flood data • Statement of Basis and Purpose – The Commission anticipates that the next iteration of the Listing Methodology will address the complexity of listing fire, flood, or other catastrophic event impacts on streams to provide further guidance for these types of decisions, and also acknowledges that there may be many case specific determinations.

2016 303(d) Listing Methodology (pg. 13): Data collected during or immediately after temporary events influencing the waterbody that are not representative of normal conditions shall typically be discounted in making the listing decision. For example, scouring storm flows which lead to diminished aquatic life use or accidental spills of toxic chemicals would not be a basis upon which to list the affected segment.

Division’s assumption: data used in assessment processes are representative of normal conditions If a party asserts that the data are not representative due to an event, then that party will evaluate the following questions

Question for workgroup: 1. What factors do we need to consider when determining whether an event creates conditions that are not representative? 2. When would we expect conditions to be representative again? Each event is unique and thus should be evaluated on a case by case basis with regard to both questions.

Question for workgroup: 1. What factors do we need to consider when determining whether an event creates conditions that are not representative? Group’s Focus: Fire and Floods

Factors to consider for fires: 1. Intensity of fire 2. Distance of waterbody to fire (within 5 miles downstream of affected area/burn zone) 3. Slope 4. Soil types 5. Geology of the area 6. Groundcover

Factors to consider for storms/floods: 1. Intensity of storms (scouring event?) 2. Storms following droughts 3. Hydrology/geomorphology 4. Slope 5. Soil types 6. Groundcover

Question for workgroup: 2. When would we expect water quality to be representative of normal conditions again?

General timeframes when considering whether data are representative after an event: Fires – Six to ten years post event (Ashley Rust research) Allow time for BAER plans or other mitigation • efforts to take effect

General timeframes when considering whether data are representative after an event: Floods/Storm Events – 4 weeks after storm or scouring event USGS Standard Operating Procedure • • Macroinvertebrates Commission supported in 2016 •

After general timeframes, conditions may: 1. Return to pre-event conditions 2. Represent new normal Regardless, listing decisions can now be made.

Listing Methodology Strategy from the 2016 Reg. #93 Statement of Basis and Purpose Condition Prior to Condition After Recommended Listing Event Recommended Action Timeframe Out of Attainment Out of Attainment 303(d) or M&E List as appropriate In Attainment or No Out of Attainment M & E List/No Action Data Out of Attainment In Attainment Remove from list

Conclusion: Division will assess all data submitted • • If a party asserts there has been an event, then we will go through the process described above concerning questions1 & 2 Attainment conclusions will only be based on data • considered representative of normal conditions Outstanding questions will be addressed through the • hearing process

Questions?