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HomeMy WebLinkAbout20190201 Ver 1_U-5747-scoping_20170511;�< „, ROY COOPER Gnrernw� MICHAEL S. REGAN Sc•crrtui�r Environmental S. JAY ZIMMERMAN Quality n�,������»� May 11, 2017 MEMORANDUM To From: Zal�id Balocl�, PE, NCDOT Project Developn�ent Rob Ridings, NC Division of Water Resources, Transportation P�i7nitting Branch Subject: Scoping comments onproposed improvements to SR 1635 in Walce County, State ProjectNo. SOl67.l.1, TIP No. U-5747 Reference your correspondence received May 1, 2017 in which you requested conm�ents for tl�e referenced project. Preliminary analysis of the �roject reveals tl�e potential for impacts to strean�s/tributar�ies, riparian buffers, andlor jurisdictional wetlands in tl�e project area. More specifically, impacts to: Stream Name River Basin & Subbasin Stream Classifications Stream Index Number 303(d) Listing? Kit Creek CPF OS WS-V; NSW 16-41-]-17-2-(0.3) No UT Crabtree Creek NEU 02 C; NSW 27-33-(l ) Yes Further investigations at a higher resolutioi� should be undertaken to verify the �resence of otller streams and/or jurisdictional wetlands in the area. In the event that any jurisdictional a�-eas are identified, the Division of Water Resotu-ces requests that NCDOT consider the following environmental issues for the proposed project: Project Spetific Comments: Kit Creelc and its tributaries are class WS-V; NSW waters of the State. The NCDWR is veiy concerned with sediment and erosion im�pacts that could result fi-om this project. The NCDWR recommends tl�at highly protective sedin�ent and erosion conh�ol BMPs be implemented to reduce the risk of nutrient runoff to these streams. Additionally, to meet the requirements of NCDOT's NPDES permit NCS0000250 the NCDWR reqliests that road design plans provide treatment of the storm water runoff tlu•ough best management practices as detailed 'u1 the most recent version of the Noy�tlz C'ar•olirza Depar•tmer�t of' Trarasportatior� Stormtivatei- Best Mnnagen�zent Practices Toolbo_r manttal. Crabtree Creek and its tributaries are class C;NSW; 303(d) iinpaired waters of the State. The NCDWR is very conceri�ed with sedimei�t and erosion i���pacts that could resiilt fi-om this project. The NCDWR recoi��mends that the most protecrive� sediment and erosion control BMPs be i��lplemented in accordance with Desigrz Stczndarcls in Sensitive Wntersheds (15A NCAC 04B .0124) to reduce the risk of further impainl�ent to these waters. Additionally, to �neet the rec�uiren�ents of NCDOT's NPDES pei-mit NCS0000250, the NCDWR rec�uests that road design plans provide treah»ent of the storm water nmoff through best management practices as detailed in the imost recent ver-sion of the Nortla Cczr-olirza De�artment of Tr•ansportatio�a Storrr�waxer Best Manngen�re��t Practices Toolhox manual. 3. This project is within the Neuse River and Jordan Lake bains. Riparian buffer impacts shall be avoided aild minimized to the greatest extent possible pursuant to 15A NCAC 2B.0233 and 15A NCAC 2B.0267. New development activities located ii1 the protected 50-foot wide riparian areas within the basin shall be limited to "uses" idei7tified within and constructed in accordance with 15A NCAC 2B.0295. Buffer mitigarion �."T^Jntf�i��� C:i,�����.are�s _ State of No�tl� Caroli��a I E�vironmental Quality I(17 Mail Service Center I Raleigh, North Carolina 27699-1617 may be required for buffer impacts resulting from activities classified as "allowable with mitigation" within the "Table of Uses" section of the Buffer Rules or require a variance under the Buffer Rules. A buffer mitigation plan, including use of the North Carolina Division of Mitigation Services, must be provided to the NCDWR prior to approval of the Water Quality Certification. Buffer mitigation may be required for buffer impacts resulting from activities classified as "allowable with mitigation" within the "Table of Uses" section of the Buffer Rules or require a variance under the Buffer Rules. A buffer mitigation plan, coordinated with the North Carolina Division of Mitigation Services, must be provided to the NCDWR prior to approval of the Water Quality Certification. General Project Comments: The environmental document should provide a detailed and itemized presentation of the proposed impacts to wetlands and streams with corresponding mapping. If mitigation is necessary as required by 15A NCAC 2H.0506(h), it is preferable to present a conceptual (if not finalized) mitigation plan with the environmental documentation. Appropriate mitigation plans will be required prior to issuance of a 401 Water Quality Certification. 2. Environmental impact statement alternatives shall consider design criteria that reduce the impacts to streams and wetlands from storm water runoff. These alternatives shall include road designs that allow for treatment of the storm water runoff through best management practices as detailed in the most recent version of the North Carolina Department of Transportation Stormwater Best Management Practices Tool box manual, such as grassed swales, buffer areas, preformed scour holes, retention basins, etc. After the selection of the preferred alternative and prior to an issuance of the 401 Water Quality Certification, the NCDOT is respectfully reminded that they will need to demonstrate the avoidance and minimization of impacts to wetlands (and streams) to the maximum extent practical. In accordance with the Environmental Management Commission's Rules (15A NCAC 2H.0506[h]), mitigation will be required for impacts of greater than 1 acre to wetlands. In the event that mitigation is required, the mitigation plan shall be designed to replace appropriate lost functions and values. North Carolina Division of Mitigation Services may be available for assistance with wetland mitigation. 4. In accordance with the Environmental Management Commission's Rules (15A NCAC 2H.0506[h]), mitigation will be required for impacts of greater than 1501inear feet to any perennial stream. In the event that mitigation is required, the mitigation plan shall be designed to replace appropriate lost functions and values. The North Carolina Division of Mitigation Services may be available for assistance with stream mitigation. 5. Future documentation, including the 401 Water Quality Certification Application, shall continue to include an itemized listing of the proposed wetland and stream impacts with corresponding mapping. 6. The NCDWR is very concerned with sediment and erosion impacts that could result from this project. The NCDOT shall address these concerns by describing the potential impacts that may occur to the aquatic environments and any mitigating factors that would reduce the impacts. 7. An analysis of cumulative and secondary impacts anticipated as a result of this project is required. The type and detail of analysis shall conform to the NC Division of Water Resource Policy on the assessment of secondary and cumulative impacts dated April 10, 2004. 8. The NCDOT is respectfully reminded that all impacts, including but not limited to, bridging, fill, excavation and clearing, and rip rap to jurisdictional wetlands, streams, and riparian buffers need to be included in the final impact calculations. These impacts, in addition to any construction impacts, temporary or otherwise, also need to be included as part of the 401 Water Quality Certification Application. 9. Where streams must be crossed, the NCDWR prefers bridges be used in lieu of culverts. However, we realize that economic considerations often require the use of culverts. Please be advised that culverts should be countersunk to allow unimpeded passage by fish and other aquatic organisms. Moreover, in areas where high quality wetlands or streams are impacted, a bridge may prove preferable. When applicable, the NCDOT should not install the bridge bents in the creek, to the maximum extent practicable. 10. Whenever possible, the NCDWR prefers spanning structures. Spanning structures usually do not require work within the stream or grubbing of the streambanks and do not require stream channel realignment. The horizontal and vertical clearances provided by bridges shall allow for human and wildlife passage beneath the structure. Fish passage and navigation by canoeists and boaters shall not be blocked. Bridge supports (bents) should not be placed in the stream when possible. 11. Bridge deck drains shall not discharge directly into the stream. Stormwater shall be directed across the bridge and pre-treated through site-appropriate means (grassed swales, pre-formed scour holes, vegetated buffers, etc.) before entering the stream. To meet the requirements of NCDOT's NPDES permit NCS0000250 please refer to the most recent version of the North Carolina Department of Transportation Stormwater Best Management Practices Toolbox manual for approved measures. 12. Sediment and erosion control measures should not be placed in wetlands or streams. 13. Borrow/waste areas should avoid wetlands to the maximum extent practicaL Impacts to wetlands in borrow/waste areas will need to be presented in the 401 Water Quality Certification and could precipitate compensatory mitigation. 14. The 401 Water Quality Certification application will need to specifically address the proposed methods for stormwater management. More specifically, stormwater shall not be permitted to discharge directly into streams or surface waters. 15. Based on the information presented in the document, the magnitude of impacts to wetlands and streams may require a Nationwide Pernut application to the Corps of Engineers and corresponding 401 Water Quality Certification. Please be advised that a 401 Water Quality Certification requires satisfactory protection of water quality to ensure that water quality standards are met and no wetland or stream uses are lost. Final pernut authorization will require the submittal of a formal application by the NCDOT and written concurrence from the NCDWR. Please be aware that any approval will be contingent on appropriate avoidance and minimization of wetland and stream impacts to the maximum extent practical, the development of an acceptable stormwater management plan, and the inclusion of appropriate mitigation plans where appropriate. 16. If concrete is used during construction, a dry work area shall be maintained to prevent direct contact between curing concrete and stream water. Water that inadvertently contacts uncured concrete shall not be discharged to surface waters due to the potential for elevated pH and possible aquatic life and fish kills. 17. If temporary access roads or detours are constructed, the site shall be graded to its preconstruction contours and elevations. Disturbed areas shall be seeded or mulched to stabilize the soil and appropriate native woody species shall be planted. When using temporary structures the area shall be cleared but not grubbed. Clearing the area with chain saws, mowers, bush-hogs, or other mechanized equipment and leaving the stumps and root mat intact allows the area to re-vegetate naturally and minimizes soil disturbance. 18. Unless otherwise autharized, placement of culverts and other structures in waters and streams shall be placed below the elevation of the streambed by one foot for all culverts with a diameter greater than 48 inches, and 20 percent of the culvert diameter for culverts having a diameter less than 48 inches, to allow low flow passage of water and aquatic life. Design and placement of culverts and other structures including temporary erosion control measures shall not be conducted in a manner that may result in dis-equilibrium of wetlands or streambeds or banks, adj acent to or upstream and downstream of the above structures. The applicant is required to provide evidence that the equilibrium is being maintained if requested in writing by the NCDWR. If this condition is unable to be met due to bedrock or other limiting features encountered during construction, please contact the NCDWR for guidance on how to proceed and to deternune whether or not a permit modification will be required. 19. If multiple pipes or barrels are required, they shall be designed to mimic natural stream cross section as closely as possible including pipes or barrels at flood plain elevation, floodplain benches, and/or sills may be required where appropriate. Widening the stream channel should be avoided. Stream channel widening at the inlet or outlet end of structures typically decreases water velocity causing sediment deposition that requires increased maintenance and disrupts aquatic life passage. 20. If foundation test borings are necessary; it shall be noted in the document. Geotechnical work is approved under Genera1401 Certification Number 3883/Nationwide Permit No. 6 for Survey Activities. 21. Sediment and erosion control measures sufficient to protect water resources must be implemented and maintained in accordance with the most recent version of North Carolina Sediment and Erosion Control Planning and Design Manual and the most recent version of NCS000250. 22. All work in or adjacent to stream waters shall be conducted in a dry work area. Approved BMP measures from the most current version of the NCDOT Construction and Maintenance Activities manual such as sandbags, rock berms, cofferdams and other diversion structures shall be used to prevent excavation in flowing water. 23. While the use of National Wetland Inventory (NWI) maps, NC Coastal Region Evaluation of Wetland Significance (NC-CREWS) maps and soil survey maps are useful tools, their inherent inaccuracies require that qualified personnel perform onsite wetland delineations prior to pernut approval. 24. Heavy equipment should be operated from the bank rather than in stream channels in order to minimize sedimentation and reduce the likelihood of introducing other pollutants into streams. This equipment shall be inspected daily and maintained to prevent contamination of surface waters from leaking fuels, lubricants, hydraulic fluids, or other toxic materials. 25. Riprap shall not be placed in the active thalweg channel or placed in the streambed in a manner that precludes aquatic life passage. Bioengineering boulders or structures should be properly designed, sized and installed. 26. Riparian vegetation (native trees and sl�rubs) shall be preserved to the maximum extent possible. Riparian vegetation must be reestablished within the construction limits of the project by the end of the growing season following completion of construction. Thank you for requesting our input at this time. The NCDOT is reminded that issuance of a 401 Water Quality Certification requires that appropriate measures be instituted to ensure that water quality standards are met and designated uses are not degraded or lost. If you have any questions or require additional information, please contact Rob Ridings at rob.ridings@ncdenr.gov or 919-707-8786. Electronic copy only distribution: Teresa Gresham, Kimley-Horn File Copy