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HomeMy WebLinkAboutU-6020-Scoping;::,.� Environmental Quality OctoUer 5, 2017 MEMORANDUM To Fro m: Stacy Oberhausen, P�, TGS Engineers ROY COOPER Goi�ernnr MICHAEL S. REGAN .sc c iz�nn, S. JAY ZIMMERMAN nr,����r��,� RoU Ridings, NC Division of Water Resources, Transportatiou Peinutting Branch Subject: Scoping comments on proposed improvements to NC 56 and SR 1215 Intersection ii� Granville County, TIP No. U6020 Reference your con-espondence received September 11, 2017 in which yo�i requested conunents for the referenced projcct Prclinvnary analysis ofthc projcct revcals tllc potcntial for possiblc impacts to strcams, buffcrs, and/or jurisdictional wetlands in the project are;a. Mare specifically, impacts to: Ri�er Stream Index Stream Name gasin/Subbnsin Stream Classifications Number 303(c� Listing? LJT Picture Creel< Neuse O1 WS-V; NSW 27-4-7 No Furthcr ulvestigations at a higl�er resolution should bc �indcrtalccn to verify the presencc of othcr sn•ean�s and/or jurisdictional wetlands u� tl�e area. In the eventtbat any j�irisdictional areas are identified, the Division of Water Rcsources rcqucsts thatNCDOT considcrthc following cnvuonmcntal issucs forthc proposcdprojcct: Project Specitic Comments: Picture Creek and its tributaries are class WS-V; NSW waters of the State. The NCDWR is veiy concemed with sediment anderosion iillpacts thatcould result fro�n tl�is project. Tl�e NCDWR recounnends that higl�ly protective sedimei�lt and erosion control BMPs be implemented to reduce the risk of nutrient runoffto Pictnre Creek. Additionally, to meet the reqilue�nents ofNCDOT's NPDES pennit NCS0000250, the NCDWR requests that road des ign plans provide treahnent of the stornl water runoffthrough best i7�anagement practices as detailed in the most recent version of tl�e Nor�th Ca�-oli��cz Depar�t�nentof Trunsportatioi� Szorn��tivaterBest MnrzagerazentPr•actices Toolbox manlial. 2. This project is within the Neuse River Basin. Riparian buffer unpacts sliall be avoided and mininvzed to the grcatcstc�cnt possiblepursuantto 15A NCAC 2B.0233. New dcvelopment activities located in tl�eprotected 50-foot wide riparian arcas witllin thc basin shall bc limited to `uses" idcntificd within and consmicted �� accordance with 15A NCAC .02B .0295. B��ffer nutigation may be required for buffer ulipacts restilting fioin activities classified as "allowable with uutigation" within the "Table ofUses" section of the Buffer Rules or requu-e a variance undertheBuffer R�iles. A buff�er initigation pla�7, u�cludu�g useofthe North Carolina Division of Mitigation Se�vices, must beprovided to the NCDWR prior to approval oftl�e Water Q�iaGty Certification. Buffer nutigation may be requued for buffer unpacts resulting from activities classified as "allowable with mitigation" within the"Table ofUses"sectionoftheBuffer Rules orrequire avariance under the Buffer R�iles. A buffer mitigation plan, coordinated with tl�e Nortl� Carolina Division ofMitigation Services, must be provided to the NCDWR prior to approval of the Water Quality Certitication. `''Ne�Thir�� Cnr��pare� _ Statc ofNorth Carolina I Enviromncntal Quality 1617 Mail Se�vicc Center I Raleigh, North Carolina 27(i99-1617 General Project Comments: The environmental document shouldprovide a detailed and itemized presentation ofthe 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 ofa 401 Water Quality Certification. 2. Environmental impact statement alternatives shall consider design criteria that reduce the impacts to streams and wetlands from stormwater runoff. These alternatives shall include road designs that allow for treatment of the storm water runoffthroughbest management practices as detailed in the most recent version of the North Carolina Department of Transportation StormwaterBest ManagementPractices Tool box manual, such as grassed swales, buffer areas, preformed scourholes, retention basins, etc. 3. 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 rninimization of impacts to wetlands (and streams) to the ma�nxm e�ent practical. In accordance with the Environmental Management Conm�ission's Rules (15A NCAC 2H.0506[h]), mitigation will berequired for impacts of greater than 1 acre to wetlands. In the event thatmitigation is required, the mitigation plan shallbe designed to replace appropriate lost functions and values. North Carolina Division of Mitigation Services may be available for assistancewith wetland mitigation. 4. In accordance with the Environmental Management Corrmrission's Rules (15A NCAC 2H.0506[h]), mitigation will be required for impacts of greater than 150 linear feet to any perennial stream In the event thatmitigation is required, themitigation plan shallbe designedto replace appropriate lostfunctions 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 ofthe proposedwetland and stream irnpacts 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 nr�pacts that may occur to the aquatic environments and any mitigating factors that would reduce the irnpacts. 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, e�avation 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 needto be included as part ofthe 401 WaterQuality 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 countersunkto 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 mstall the bridge bents in the creek, to the maximum eadent practicable. 10. Wheneverpossible, theNCDWR 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.Fishpassageandnavigationbycanoeistsandboatersshallnotbeblocked. 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 andpre-treatedthroughsite-appropriatemeans(grassedswales,pre-fornied scourholes,vegetatedbuffers,etc.) before entering the stream To meet therequirements ofNCDOT's NPDES permit NCS0000250], pleaserefer to the most recent version ofthe North CarolinaDepartment ofTransportation StormwaterBest Management Practices Toolboxmanual for approvedmeasures. 12. Sediment and erosion control measures should not be placed in wetlands or streams. 13. Borrow/waste areas should avoid wetlands to the ma�mum e�ent 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 theproposed methods for stormwater management. More specifically, stormwater shall notbe permitted to discharge directly into streams or surfacewaters. 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 advisedthata401 WaterQuality Certification requires satisfactoryprotectionof water quality to ensure that water quality standards are met and no wetland or stream uses are lost. Final permit 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 minirnization of wetland and stream impacts to the maximum ea�tent 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 streamwater. 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 ternporary 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, orother mechanized equipment and leaving the stumps and root mat intact allows the area to re-vegetate naturally and minimizes soil disturbance. 18. Unless otherwise authorized, placement ofculverts and otherstructures 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 ofwater and aquatic life. Design andplacement 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, adjacent 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 otherlimiting features encountered during construction, please contact the NCDW R for guidance on how to proceed and to deternvne whether or not a permit modification will be required. 19. If rnultiple pipes or banels are required, they shall be designed to mimic natural stream cross section as closely as possibleincluding pipes orbarrels at flood plain elevation, floodplain benches,and/orsills 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 General 401 Certification Number 3883/Nationwide Pernut No. 6 for Survey Activities. 21. Sediment and erosion control measures sufficient to protect water resources must be implemented and maintamed in accordance with the most recent version of North Carolina Sediment and Frosion Control Planning andDesign Manual andthe most recent version ofNCS000250. 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,rockberms, cofferdams and otherdiversion structures shallbe usedto prevente�avation in flowing water. 23. While the use ofNational Wetland Inventory (NWn maps, NC Coastal Region Evaluation of Wetland Significance (NC-CREWS) maps and soil survey maps are useful tools, their inherent inaccuracies require that qualified personnelperform onsite wetland delineations prior to pern�it 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 shouldbeproperly designed,sized and installed. 26. Riparian vegetation(nativetreesandshrubs)shallbepreservedtothemaximum ea�tentpossible. Riparian vegetation �st 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 rerninded that is suance of a 401 W ater 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 orrequire additional inforn�ation, please contact Rob Ridings at 919-707-8786.