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Home My WebLink About20130223 Ver 7_Self reporting non-compliance_20190306Carpenter,Kristi From: Sent: To: Cc: Subject: Norton, Apri) R Thursday, March 07, 2019 2:55 PM Thomson, Nicole J Eason, Patty P; Parker, Jerry A; Moon, Chris D; Cvijetic, Bojan; Snell, William H; Della Moore; Cheely, Erin K; Chapman, Amy; 'Bailey, David E CIV USARMY CESAW (USA)' RE: U-2524C/D; Greensboro Western Loop; WBS 34820.3.30 The Division of Water Resources acknowledges your self-reporting non-compliance. The project Certi�i_caticr_n.._crF._Ccr_rrr�.�a.leticr_n shall be completed within 30 days. April From: Thomson, Nicole J Sent: Wednesday, March 06, 2019 3:37 PM To: David.E.Bailey2@usace.army.mil; Norton, April R<april.norton@ncdenr.gov> Cc: Eason, Patty P<peason@ncdot.gov>; Parker, Jerry A<jparker@ncdot.gov>; Moon, Chris D<cdmoon@ncdot.gov>; Cvijetic, Bojan <bcvijetic@ncdot.gov>; Snell, William H <wsnell@ncdot.gov>; Della Moore <dmoore@rkk.com>; Cheely, Erin K <ekcheely@ ncdot.gov> Subject: U-2524C/D; Greensboro Western Loop; WBS 34820.3.30 Importance: High Good afternoon — The Division became aware last week (02/26/19) that the USACE and DWR Authorizations for the above project expired on 12/30/18. After discussion with Division staff, we are confidant that all permit sites (i.e. stream and wetland areas — aka "bottom work") have been completed for this project. In other words, the Division is aware and will be reiterating to its contractors that there cannot and will not be any work within any areas that are subject to the Federal 404 and State 401, without requesting authorization from your respective agencies. As a reminder, this project was determined to be "exempt" from the Jordan Riparian Rules in locations within the project study area (see attached FEIS mapping 1995 PDF). As was also discussed, on U-2524 C there is one lateral ditch that has not been constructed at this time; this ditch conducts flow from the Hazardous Spill Basin (HSB) located on the "D" phase of the project. Originally, this ditch was to tie in to Horsepen Creek with rip rap placed below the ordinary high water mark (OHWM) which would be a regulated activity. The Division is exploring other options (i.e. rip rap dissipater pad, matting, etc.) in upland areas to avoid this impact to the resource. In October, the Division became aware of stream instability near Permit Site 4(STA 477+50 to 478+25 Left). The culvert was constructed and buried 1-foot below the existing stream bed elevation (per the approved plan). This culvert also has no sills or baffles. The bed load of the system is very silty and loaded with mica, typical of the urban streams in this area. During the late summer/early fall Greensboro experienced record rain falls including 2 tropical storms and 1 hurricane. The entire area has seen extensive flooding and overtopping events which have caused many wash outs not only on this project, but numerous others in the Division. The material in the culvert ultimately scoured out to the concrete floor. Upstream of the culvert, the system has begun to erode — the original stream was 2.5 to 3.5 feet wide. Class I rip rap was installed along the embankment per the approved plans and stoped just before a transition to pre-existing Class B bank stabilization (put there by others prior to the project beginning). The flows this system has seen have effectively stripped the embankment away. The system is now much wider as a result and has a vertical head- cut located near the 4-inch ductile iron pipe for sewer clean out (just upstream of the culvert inlet). The utility work did not cause the instability. The 8-inch sewer main was installed via an open cut (per the approved plans) and is buried approximately 5 feet below the stream bed. Ultimately, the poor bed material and significant flooding have resulted in scour which has now created elevation and velocity issues which has resulted in further stream instability for a distance of approximately 70-feet above the inlet of the culvert crossing. Attached is a PDF of the original Site 4 Permit Drawing and a Photo log showing before and after images. In review of the authorizations issued for this project, the Division found the following: From the USACE Authorization "Special Conditions" — 3. MAINTAIN CIRCULATION AND FLOW OF WATERS: Except as specified in the plans attached to this permit, no excavation, fill or mechanized land-clearing activities shall take place at any time in the construction or maintenance of this project, in such a manner as to impair normal flows and circulation patterns within waters or wetlands or to reduce the reach of waters or wetlands. 16. TEMPORARY IMPACTS RESTORATION MEASURES: Temporary discharge of excavated or fill material into wetlands and waters of the United States will be for the absolute minimum period of time necessary to accomplish the work. All authorized temporary wetland, stream, and tributary impacts will be returned to pre-disturbance grade and contour, and re- vegetated. In wetland areas where pipeline installation via trenching is authorized, wetland topsoil will be segregated from the underlying subsoil, and the top 6 to 12 inches of the trench will be backfilled with topsoil from the trench. 21. CULVERTS: B. Measures will be included in the construction/installation that will promote the safe passage of fish and other aquatic organisms. The dimension, pattern, and profile of the stream above and below a pipe or culvert should not be modified by widening the stream channel or by reducing the depth of the stream in connection with the construction activity. The width, height, and gradient of a proposed opening should be such as to pass the average historical low flow and spring flow without adversely altering flow velocity. Spring flow should be determined from gauge data, if available. In the absence of such data, bankfull flow can be used as a comparable level. From the NC DWR Authorization, "General Permit Conditions" — � 22. Unless otherwise approved in this certification, placement of culverts and other structures in open 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, adjacent to or upstream and down stream of the above structures. The applicant is required to provide evidence that the equilibrium is being maintained if requested in writing by NCDWQ. If this condition is unable to be met due to bedrock or other limiting features encountered during construction, please contact NCDWQ for guidance on how to proceed and to determine whether or not a permit modification will be required. 25. The dimension, pattern and profile of the stream above and below the crossing shall not be modified. Disturbed floodplains and streams shall be restored to natural geomorphic conditions. Therefore, in order for the Division to be compliant with the above specific conditions at Site 4, the Division proposes the following repairs to correct the stream instability (see attached "Revised Sheet 12a of 25" and "Engineering Response" PDFs): • Create a series of step-downs utilizing 4 x 3 x 2 foot boulders at this location to address the bankfull shear stress (approximately 3.4 Ibs/sf) • Bury the steps approximately 6 inches • Key the steps into the banks • Utilize geotextile fabric under the boulders to insure long-term stability • Replace the missing and/or Class B rip rap with Class I rip rap along the stream bank between the in-stream structures and the culvert inlet. All of this proposed work falls within the 70 linear feet described between the 4-inch sanitary sewer cleanout pipe and the culvert inlet. The Division believes this proposal will address the instability issues (similar to Site 7) and successfully restore the normal flow regime in this system (i.e. re-stablish a stable pattern, dimension and profile). Please advise with your thoughts and/or concurrence on our approach. Thank you in advance — Nikki Nicole J. Thomson, PWS Division Environmental Supervisor Assistant Division Environmental Office 919-754-7806 Mobile Nithomson2(c�ncdot.qov PO Box 14996 Greensboro, NC 27415-4996 � } �: ��. � ��..x a�� ,��s�� `��,� ��,�,� �,� ,��.�� `�� 'J��`� �°�� .�� :�,� ��W�r �� .� �� ,��,�� :s��,�. I rr�7all �:urrc,��u � � � � � � � � y I�c rli��;lu�e,rl �u �C�h•ih�rl I i� ci��;e, Cu ai� rur°r7 �mii;, ;;e,i� cr i;, ;;u� ��;� �u Cmie, ,..,u� i�; ta�:ur�: ;, ..,aw ai� ir7a, I�arti��,