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HomeMy WebLinkAbout20120748 Ver 1_USACE Approval Letter SAW 2012-01101_20120824DEPARTMENT OF THE ARMY WILMINGTON DISTRICT, CORPS OF ENGINEERS 69 DARLINGTON AVENUE WILMINGTON, NORTH CAROLINA 28403 -1343 REPLY TO ATTENTION OF August 24, 2012 Regulatory Division Re: NCMT Review and USACE Approval of the Junes Branch Mitigation Plan (SAW 2012 - 01101) Ms. Suzanne Klimek North Carolina Ecosystem Enhancement Program 1652 Mail Service Center Raleigh, NC 27699 -1652 Dear Ms. Klimek: The purpose of this letter is to provide the North Carolina Ecosystem Enhancement Program (NCEEP) with all comments generated by the North Carolina Interagency Review Team (NCMT) during the 30 -day comment period for the Junes Branch Mitigation Plan, which closed on August 8, 2012. These comments are attached for your review. Based on our review of these comments, we have determined that no major concerns have been identified with the Draft Mitigation Plan. However, the minor issues with the Draft and discussed in the attached comments, must be addressed in the Final Mitigation Plan. The Final Mitigation Plan is to be submitted with the Preconstruction Notification (PCN) for Nationwide permit approval of the project along with a copy of this letter. Issues identified above must be addressed in the Final Mitigation Plan. Please be sure that all updates to the Mitigation Plan are specifically identified in a table at the front of the Mitigation Plan. This helps expedite our review of the Final Mitigation Plan and issuance of the Nationwide Permit. If it is determined that the project does not require a Department of the Army permit, you must still provide a copy of the Final Mitigation Plan, along with a copy of this letter, to the appropriate USACE field office at least 30 days in advance of beginning constriction of the project. Please note that this approval does not preclude the inclusion of permit conditions in the permit authorization for the project, particularly if issues mentioned above are not satisfactorily addressed. Additionally, this letter provides initial approval for the Mitigation Plan, but this does not guarantee that the project will generate the requested amount of mitigation credit. As you are aware, unforeseen issues may arise during constriction or monitoring of the project that may require maintenance or reconstruction that may lead to reduced credit. Thank you for your prompt attention to this matter, and if you have any questions regarding this letter, the mitigation plan review process, or the requirements of the Mitigation Rule, please call me at 919- 846 -2564. Sincerely, Dlg pally slg ned by A 01 M I ,CRUMB LEY.TYLER.AUTRY.10 ��9r.07509975 Ito', l 4'sbV �i jDate:2012.082413:23:39 04'00' Tyler Crumbley Regulatory Specialist Enclosures Electronic Copies Furnished: NCIRT Distribution List CESAW -RG -A /Brown Jeff Jurek, NCEEP Paul Wiesner, NCEEP REPLY TO ATTENTION OF DEPARTMENT OF THE ARMY WILMINGTON DISTRICT, CORPS OF ENGINEERS 69 DARLINGTON AVENUE WILMINGTON, NORTH CAROLINA 28 403 -1 343 CESAW- RG /Crumbley August 8, 2012 MEMORANDUM FOR RECORD SUBJECT: NCIRT Comments During 30 -day Mitigation Plan Review Purpose: The comments and responses listed below were posted to the NCEEP Mitigation Plan Review Portal during the 30 -day comment period in accordance with Section 332.8(g) of the 2008 Mitigation Rule. NCEEP Project Name: Junes Branch Mitigation Project, Jackson County, NC USACE AID #: SAW- 2011 -01101 30 -Day Comment Deadline: August 8, 2012 1. Eric Kulz, NCDWQ, July 24, 2012: • 1 have questions regarding the rationale and explanation for P1 restoration of Bumgarner Branch Reach 1a. The designer states that due to livestock and herbaceous vegetation on the banks the stream bed is narrow. It is not excessively incised and has connection to its floodplain. I have not been able to find the bank height ratio in the report. It says that the channel will widen and become unstable and overwiden once cattle are excluded and woody vegetation replaces herbaceous vegetation. This appears contrary to generally- accepted stream assessment and restoration principles. • The permanent seed mix consists of white clover, orchard grass, creeping red fescue, Korean lespedeza, and birdsfoot trefoil. All but red fescue are exotic and are not listed as noxious, but the USDA plants database says they all have the potential to become weedy or invasive. DWQ recommends using a native riparian seed mix, a number of which are available through native plant nurseries. NCEEP Response, August 1, 2012: The following is a response from the project designer (Wolf Creek Eng.) to DWQ's 7/24/12 comments: • The reviewer states that he is unable to find the bank - height- ratios, however, the bank - height- ratios are stated in Section 2.2.6 of the narrative. Specifically for the reach in question in paragraph 4 under the "Bumgarner Branch" subsection of 2.2.6, the report states that the bank - height- ratios range from 1.1 to 1.5. Additionally, the field data collected for this project can be found in Appendix C4. Specifically, the table titled "Site Assessment Calculations" has data collected on the upstream end of Bumgarner Branch (Section Numbers 6, 7 and 16 and designated in the "Reach" and "Location" rows as "Bumgarner -U /s of road ", "Bumgarner -mid horse pasture" and "Bumgarner -u /s end ") indicates bank - height- ratios of 1.5, 1.1 and 1.5. The reviewer states that the report claims the channel will "over -widen once the cattle are excluded" and that this is "contrary to generally accepted stream assessment and restoration principles." First, there is no claim in the report that the channel will "over- widen," simply that the width of the bed of the channel will increase from its present excessively narrow width of approximately 3 ft. to a more geomorphically stable width of at least 8 ft. As stated in the report, this projected dimension is based on data collected on reference and naturalized streams in the surrounding watersheds and in the mountain region. Data on more than 30 locations were collected for this project and is depicted in the graphs in Appendix C1. The concept that a stream will widen from an unsustainably narrow condition to a more appropriate width is neither novel or contrary to generally accepted stream principles. Perhaps what is an encumbrance is the idea that exclusion of livestock will facilitate this process or that the presence of livestock perpetuates the existing condition. However, experience and observation suggest that the presence of livestock can prevent the natural succession from herbaceous vegetation to woody vegetation and without the presence of woody vegetation the herbaceous vegetation will provide a denser ground cover. In some cases, as in the present situation, this denser ground cover can temporarily retard soil erosion. As stated paragraph 3 of Section 7.2.1 of the report, this is demonstrated immediately upstream of the site where livestock access is restricted, woody vegetation in the form of privet and alder have become established, and the channel bed has widened to 6 ft. with every indication that it will widen further. • The reviewer states that the permanent seed mix contains exotic species. The seed mix included in this project is not the standard native mix that we have used in the past. This seed mix was directed by EEP on our last EEP project (Middle South Muddy Creek). There were no unusual soil conditions on that project so my understanding was that this was the preferred seed mix by EEP and was therefore carried over to this project. If this is not the case we would recommend a permanent seed mix containing Broom Sedge, Deer Tongue, Switch Grass, Indian Grass, Eastern Gama Grass and Joe -Pye -Weed. Eric Kulz. NCDWQ. August 7. 2012: • 1 had a productive and interesting discussion with Grant Ginn regarding Bumgarner Branch. The design dimension for this reach is supported by the regional curves, and the proposed design is supported by DWQ. DWQ maintains the recommendation that the permanent seeding mix consist of native riparian species, and not the list proposed in the draft plan. 2. Todd Tugwell, USACE, June 25, 2012: • The performance standards included in Section 9.0 of the Draft Mitigation Plan are generally more specific than required by the 2003 Stream Mitigation Guidelines (SMGs). Additional standards have been included that may result in situations determined to be unacceptable during review of the monitoring reports or at project closeout, such as the standard that the Entrenchment Ration remain below 1.3. Another example is included under "Surface Water Hydrology" where it states that the surface water gauge must achieve bankfull or greater elevations at least twice, but it does not indicate that these events must occur in separate years, as required by the SMGs. Please note that the project will be held to the currently accepted performance standards as stated in the 2003 SMGs, and the project should state so in Section 9.0. • Forested buffer widths along the channel appear to be less than 30 feet in some areas (see Sta 111 +50 on Doris Branch), and just over 30 feet for much of the rest of the project. Be verify that buffer widths are wide enough to meet the minimum standard for mountain counties (30 feet minimum) after project construction and anticipated channel adjustments have occurred. • Based on a review of Figure 7 and Preliminary Construction Plans (Site Plan aerial image), there appears to be a structure that extends into the proposed Conservation Easement area. Please verify whether this structure is located in the proposed easement and revise the plan if necessary. • Wetland areas located within the project boundary should be protected from impact by construction traffic by fencing. If impacts to wetland are anticipated, be sure that all impacts are avoided where possible and minimized where unavoidable. The Preconstruction Notification (PCN) application must account for all temporary and permanent impacts to wetlands. • Please note that due to the location of this project, additional information regarding potential impacts to resources protected under Section 106 of the National Historic Preservation Act, beyond what is listed in the Categorical Exclusion Checklist included in Appendix A, will be required during the permit review. This information should be included in the PCN application, but does not have to be included in the Final Mitigation Plan. NCEEP Response, August 1, 2012: The following is a response from the project designer (Wolf Creek Eng.) to USACE's 7/25/12 comments: • We will revise the performance standards to be consistent with the 2003 SMG and include a statement in the narrative to indicate the intended compliance. All buffer widths have been checked to be 30 ft. or greater. We can revise the alignment at the lower end of Doris Branch to provide slightly more than 30 ft. if required, however, given the small size of this stream it is unlikely that channel pattern adjustments will occur following construction. The structure that appears in Figure 7 to be inside of the easement no longer exists. This is simply an outdated aerial image. If necessary we can photoshop this structure out of the image. There is no need for the construction activities to impact the wetlands. We will add a statement to the report narrative, Section 7.2.2, indicating that the wetlands will be protected from construction activities and final construction plans will indicate locations for protective fencing around these sensitive areas.