401 Certification Update. Windy Gap Firming Project

Transcription

1 401 Certification Update Windy Gap Firming Project

2 Windy Gap Project

3 Windy Gap Firming Project

4 Windy Gap Firming Project 90,000 acre-foot reservoir (Chimney Hollow) Reservoir filled directly with WG water or by exchange using C-BT water (Prepositioning) Deliveries by exchange from Carter Lake and Horsetooth or directly, when necessary

5 WGFP Permitting DEIS 2008 FEIS 2011 Grand County 1041 Permit 2012 Carriage Contract - December 2014 USBR ROD December 2014 CDPHE 401 Water Quality Certification 2016 USACE 404 permit (Pending) Spring 2017

6 WGFP 401 Certification Application Public tice May: Comments Response 30 day 401 Certification Public Comment 404 Permit Submitted March 30, 2015 rthern Water to handle comments WQCD to consider/include comments in final permit conditions Conditional March 25, 2016 Pending Spring 2017

7 Regulatory Framework CWA Section 404 : USACE Permit required to construct Chimney Hollow CWA Section 401: Required when Federal (USACE) permit is needed Colorado Reg 82 : address direct and indirect impacts direct impacts = construction activities, addressed in the Stormwater Management Plan For WGFP: WGPF is NOT a discharge = rest of the impacts are indirect

8 Significant Degradation Test For bioaccumulative toxic pollutants: the new or increased loading from the activity is less than 10 percent of the existing total load to that portion of the segment impacted by the discharge For all pollutants: the new activity or increased discharge will consume less than 15 percent of the baseline available increment, provided that the cumulative increase in concentration from all sources shall not exceed 15 percent of the baseline available increment. The baseline available increment is the increment between low-flow pollutant concentrations and the relevant standards for critical constituents for that portion of the segment impacted by the discharge. The baseline low-flow pollutant concentration shall represent the water quality as of September 30, 2000

9 Antidegradation Review Process Review not required PROCEED with certification SIGNIFICANCE DETERMINATION (SCT TEST) New or increased WQ impact from regulated activity in reviewable segment? NECESSITY OF DEGRADATION DETERMINATION (NECESSITY TEST) Important economic or social development? STOP Degradation not significant PROCEED with certification Will significance thresholds be exceeded? Reasonable water quality control alternative available? Select this alternative Degradation not significant: Incorporate enhancements or mitigation PROCEED Impacts offset by env. benefit, WQ enhancement or mitigation measure? Conclusion: Significant Degradation Conclusion: Degradation Necessary PROCEED with certification

10 Significant Degradation Test 1 Model Cumulative Effects (CE) Existing Conditions (EC) Water quality standard 2 Baseline Available Increment (BAI) Significant Concentration Threshold (SCT)= BWQ+15% BAI <SCT? Baseline Water Quality (BWQ)

11 Antidegradation Review Conclusions Summary Quantitative/ Qualitative Significant Degradation Test Mitigation/ Enhancement Measures

12 Water Quality Parameter Temperature Nutrients Total Phosphorus Dissolved Oxygen Geographic Scope Colorado River Fraser Three Lakes Shadow downstream of Mountain Windy Gap Reservoir Monitoring Sites Real Time at: Windy Gap Hot Sulphur Williams Fork Start ASAP or within 1 yr of 404 Permit Effluent (TP and TN), monthly When WWTP upgraded GR-DAM, SM- DAM, GL-MID TP, TN Monthly ASAP or within 1 yr of 404 Permit GR-DAM SM-DAM GR-PUMP Monthly ASAP or within 1 yr of 404 Permit Aquatic Life Mercury Manganese General Colorado River downstream of Windy Gap Annually at: Windy Gap upstream Windy Gap downstream At Pioneer Park +2 TBD ASAP or within 1 yr of 404 Permit Three Lakes, Carter, Horsetooth, Chimney Hollow Fish tissue Biennially all existing lake/reservoirs annually in Chimney Hollow First field season after 404 Permit First field seasons after construction f Chimney Hollow Colorado River from Granby to downstream of Windy Gap TBD Chimney Hollow CH-DAM General chemistry, metals, nutrients, physical parameters, zooplankton, phytoplankton Monthly (except winter) Upon construction of Chimney Hollow Duration At least 5 yrs 2 yrs if after WGFP fully upgrades operational successful At least 5 yrs after WGFP fully operational At least 5 yrs after WGFP fully operational At least 5 yrs after WGFP fully operational At least 5 yrs after WGFP fully operational Chimney Hollow: until levels below TBD At least 5 yrs after WGFP fully operation

13 WGFP 401 Certification Monitoring Requirements Manganese Manganese Water Quality Nutrients (TP, TN) Nutrients (TP, TN) Dissolved Oxygen Dissolved Oxygen Biomonitoring +2 sites TBD Mercury Mercury Temperature Temperature

14 Monitoring Annual Report 12 months Is there impairment? Impairment Investigation Report End of Process Is the WGFP operation primarily responsible? 303d listing & TMDL Actively explore Category 4b Plan 2 years Is a Category 4b Plan feasible? Develop Category 4b Plan 303d listing & TMDL