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HomeMy WebLinkAbout20161200 Ver 1_USACE eApproval Letter_20200601Strickland, Bev From: Browning, Kimberly D CIV USARMY CESAW (USA) <Kimberly.D.Browning@usace.army.mil> Sent: Monday, June 1, 2020 9:55 AM To: Baumgartner, Tim Cc: Barbara A Doll; Allen, Melonie; Tugwell, Todd J CIV USARMY CESAW (US); Haupt, Mac; Davis, Erin B; Haywood, Casey M CIV USARMY CESAW (USA); Merritt, Katie; Wilson, Travis W.; Bowers, Todd; kathryn_matthews@fws.gov; Crumbley, Tyler A CIV USARMY CESAW (USA); McLendon, C S CIV USARMY CESAW (USA); Lastinger, James C CIV USARMY CESAW (USA) Subject: [External] eApproval Letter/ NCDMS Millstone Creek Mitigation Site/ Randolph County/ SAW-2019-01363 Attachments: eApproval Letter -Millstone Creek_SAW-2019-01363.pdf, Draft Mit Plan Comment Memo -Millstone Creek_2019-01363.pdf, Response to Comments Final.pdf Follow Up Flag: Follow up Flag Status: Completed 1111910AMernal email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to 1vort.spam@nc.gov Mr. Baumgartner, Attached is the Millstone Creek Mitigation Site Draft Plan approval letter and copies of all comments generated during the project review. Please note that this letter approves the Draft Mitigation Plan provided that the Final Mitigation Plan adequately addresses all comments on the attached memo. Please provide a copy of the Final Mitigation Plan when you submit the Preconstruction Notice for the NWP 27. Also, please ensure that a copy of the Final Mitigation Plan is posted to the NCDMS project documents so that all members of the IRT have access to the Final plan. Please let me know if you have any questions about the process or the attached letter. Respectfully, Kim Browning Mitigation Project Manager, Regulatory Division I U.S. Army Corps of Engineers 3331 Heritage Trade Dr, Ste. 105 1 Wake Forest, NC 27587 1 919.554.4884 x60 BUILDING STRONG REPLY TO ATTENTION OF: Regulatory Division DEPARTMENT OF THE ARMY WILMINGTON DISTRICT, CORPS OF ENGINEERS 69 DARLINGTON AVENUE WILMINGTON. NORTH CAROLINA 28403-1343 June 1, 2020 Re: NCIRT Review and USACE Approval of the NCDMS Millstone Creek Site Draft Mitigation Plan / Randolph Co./ SAW-2019-01363/ NCDMS Project # 204 Mr. Tim Baumgartner North Carolina Division of Mitigation Services 1652 Mail Service Center Raleigh, NC 27699-1652 Dear Mr. Baumgartner: The purpose of this letter is to provide the North Carolina Division of Mitigation Services (NCDMS) with all comments generated by the North Carolina Interagency Review Team (NCIRT) during the 30-day comment period for the Millstone Creek Draft Mitigation Plan, which closed on March 7, 2020, and a response to comments was received May 17, 2020. 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, which is considered approved with this correspondence. However, several minor issues were identified, as described in the attached comment memo, which must be addressed in the Final Mitigation Plan. The Final Mitigation Plan is to be submitted with the Preconstruction Notification (PCN) Application 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. All changes made to the Final Mitigation Plan should be summarized in an errata sheet included at the beginning of the document. 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 construction 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 construction 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 919-554-4884, ext 60. Sincerely, Digitally signed by BROWN ING.KIMBERLY• BROWN ING.KIMBERLY.DANIELLE. DAN I E LLE.152768351 O 1527683510 Date: 2020.06.01 09:08:16-04'00' Kim Browning Mitigation Project Manager for Tyler Crumbley Enclosures Electronic Copies Furnished: NCIRT Distribution List Melonie Allen—NCDMS Barbara Doll—NCSU DEPARTMENT OF THE ARMY WILMINGTON DISTRICT, CORPS OF ENGINEERS 69 DARLINGTON AVENUE WILMINGTON, NORTH CAROLINA 28403-1343 REPLY TO ATTENTION OF: CESAW-RG/Browning MEMORANDUM FOR RECORD March 27, 2020 SUBJECT: Millstone Creek Mitigation Site - NCIRT Comments during 30-day Mitigation Plan Review PURPOSE: The comments listed below were received during 30-day comment period in accordance with Section 332.8(g) of the 2008 Mitigation Rule in response to the Notice of NCDMS Mitigation Plan Review. NCDMS Project Name: Millstone Creek Mitigation Site, Randolph County, NC USACE AID#: SAW-2019-01363 NCDMS #: 204 30-Day Comment Deadline: March 7, 2020 DWR Comments, Mac Haupt & Erin Davis: 1. Page 7, Table 1.1 — The 1:1 ratio proposed for NT R2, UTA R2 and UTB do not appear appropriate for the outlined E1 level approaches. However, DWR appreciates that proactive enhancement activities, such as cattle exclusion, have been implemented and are contributing to functional uplift. DWR would support a 1.5:1 ratio for the three proposed E1 / R equivalent reaches. 2. Page 28, Section 5.1 — The USFWS website was consulted on August 27, 2007. Please revisit this source to confirm that there have been no changes to listed species. 3. Page 35, Section 8.2 — Should Header be labeled as UTA R1 instead of UTA R2? 4. Page 36, Section 8.2.1 — DWR is concerned that by raising the channel bed by 5-6 feet at the top of UTA R1 and NT R1 that flow may not be maintained, and jurisdictional stream status may be lost. Flow documentation in the upper sections of these reaches will be critical. 5. Page 39, Section 8.2.4 — Please correct UTA R2 and UT R2 to UTA R1. 6. Page 48, Table 8.9 — Are live stakes included in the stem counts (e.g. silky dogwood)? If not, please include live stake species and estimated quantities. 7. Page 52, Section 8.7 — Are sod mats still being proposed? They do not appear in the design sheets. If proposed, please add a typical detail. 8. Page 53, Section 8.9 #3 — The proposed transition from perennial single thread channel to wetland will be an area to monitor for signs of instability. Additionally, with the wetland ditch plugged and the previously proposed log -step outfall not included in this design version, monitoring any concentrated flow areas developing between the wetland and Mill Creek for instability will also be important to address. 9. Page 56, Section 9.5 — The proposed wetland enhancement is based on hydrologic functional uplift, as such DWR recommends the hydrologic performance criteria of a minimum 8 percent hydroperiod. DWR also requests an additional wetland groundwater gauge, for a total of two wetland monitoring gauges. 10. Page 56, Section 10 — Please confirm that the record drawings and baseline monitoring report will be submitted after completion of Phase 2 construction. Phased monitoring periods are not proposed, correct? 11. Design Sheets - Please include the following items: a. Location of existing and proposed fencing; b. Details: ford crossing, BMP wetland feature, ditch plug (specify minimum plug width), ditch filling/partial filling (specify maximum depth from ground surface to be filled), live stake installation, bare root and container planting 12. Figure 10.1 a. In order to monitor the minimum 30-day consecutive flow performance standard, please add flow gauges to NT R1 and UTA R1, within the upper one-third of each reach. b. DWR requests an additional cross section along the lower section of MC R1 and an additional wetland groundwater gauge. c. Please show the easement boundaries. USACE Comments, Kim Browning: 1. When submitting the PCN, please include an estimate of the number of trees, or acres, to be cleared for the NLEB 4(d) Rule. 2. Please QA/QC this document for grammar and typos. 3. There is conflicting information throughout the plan: Page 12 states that Millstone Creek is the only perennial channel on site, while pages 22 and 39 indicate that all channels are perennial. Page 31 states that tributaries have little to no flow. NCSAM forms indicate channels are perennial. Please adjust the text for consistency. 4. Table 1.1: a. The 2016 NCIRT Guidance specifies that additional credit of up to 2% may be generated for each tributary to be monitored for water quality. At a minimum, water quality and macroinvertebrate sampling must be conducted to receive the additional credit. Additional credit is eligible on restored and enhanced reaches of stream channels with the intent of linking stream mitigation and functional uplift. The IRT will authorize 4% additional credits for streams only on this site. b. Water Quality credits are not authorized for wetlands. c. The 2% increase proposed for success on At -Risk Tribs is not authorized. d. Please carry out stream credits to at least two decimal places, and avoid rounding. e. Please show how the credits are being calculated by reach length, total credits, and 4% increase per reach. For example, Reach NTR1 is proposed for 326 LF (existing 303 LF), 326 SMUs, and 13.04 additional credits at 4%. Please see example revision at the end of this document. 5. Reaches proposed for El with a R Equivalent should be credited at 1.5:1, not 1:1 as proposed. The proposed work appears to be standard Enhancement I, defined as any stream mitigation activity that does not involve restoration of the entire stream channel. The only section that appears to meet restoration activities is on UTB near the bend at station 16+00. Additional credit for WQ monitoring is already being awarded on these reaches, and therefore is not justification for a 1:1 ratio. Bank grading, in -stream structures, and buffer planting meets the criteria for El at 1.5:1. Additionally, NTR1 is already receiving a 1:1 ratio, and the WQ treatment on that reach is not justification to increase the ratio on other reaches. Since cattle are currently excluded from project reaches, that is not justification for an increased ratio. 6. Categorical Exclusion Documents should be updated. The response letter from SHPO dated December 12, 2003 is sufficient. However, please update the NCWRC and USFWS documents with current T&E species. I did receive an email response to the Public Notice from FWS on Aug. 13, 2019 stating that they have no significant concerns with this project. 7. Page 32: Is there a WQ monitoring station downstream of the ford crossing? 8. Table 7.1 indicates that livestock exclusion fencing will be installed. It is unclear where fencing currently exists. Please indicate on a map or in the plan sheets. 9. Please include the water quality monitoring locations on the Monitoring Map. 10. Wetland enhancement area should demonstrate functional uplift. The performance standard for the wetland should be a minimum of an 8% hydroperiod, and pre -well data should be provided in order to show uplift. Additionally, a discussion of the NCSAM functional assessment rating as LOW for habitat might be helpful. a. Please add a vegetation monitoring plot to the wetland area to ensure that with increased hydrology the vegetation is not negatively impacted. 11. Please address how fescue will be treated/removed. 12. It appears that the majority of the site has buffer widths that exceed the minimum 50 feet. Since there is only one crossing on the site and you are capturing the terminal ends of the tributaries, you may want to consider running the Buffer Tool on the project to see if you can get the additional 2% buffer credit. The crossing and the wetland area will need to be clipped from the buffered area for credit. If it turns out to be beneficial, please include the GIS map and corresponding table. 13. Design sheets: Several sheets are upside down and out of order, and there are three sheets labeled page 4.5. Please correct. a. Please include a ditch plug detail. 14. There is concern for hydrologic trespass to occur since the ditch entering the wetland will be plugged and there is no planned outlet for the wetland. 15. Page 39, Section 8.2.4: Please QA/QC this paragraph for stream labeling. Also, to be clear about phased construction over a two-year period, the initial credit release will not occur until the Record Drawing/As-Built is received and approved. 16. Ford Crossing: There is some concern with the amount of sediment coming into the system. Without seeing the design detail it's difficult to discern whether the structure will have an upstream and downstream sill to hold elevation and retain substrate in place. Will it be designed to incorporate reinforcing underlying material? 17. Page 53, #1: with the amount of sediment coming into the system, is there a concern that the pools will fill in over time, decreasing bedform diversity? 18. Beaver were mentioned in the document, please add this t the Risks/Uncertainties section. At the end of this memo there are some EXAMPLE risks to consider. 19. Page 54, Section 9: Please remove the statement "If all performance standards have been successfully met, NCDMS may propose to terminate stream, wetland and/or veg monitoring after MY5." 7 years of monitoring is required. 20. Section 9.4: There will be no loss of credits if this performance standard is not met; however, the additional 2% for NTR1, NTR2, UTAR1 and UTB are not approved. 21. Table 10.1: The section that discusses exclusion of livestock from channels is unclear whether fencing is existing or planned. The treatment for this section should be to install or maintain livestock exclusionary fencing. The discussion of the conservation easement establishment should be under site protection. 22. Section 10.4: Please see the end of the document for example phrasing for the Adaptive Management section. 23. Section 11: Please revise based on correct ratios. 24. General note: It's helpful when all maps and figures are located in one section of the plan. BROWNING.KIM Digitally signed by BROWN ING.KIMBERLY.DANI Kim Browning BERLY.DANIELLE ELLE.1527683510 Mitigation Project Manager Date: 2020.03.27 15:26:33 .1527683510-04'00' Regulatory Division Example of how to revise Table 1.1: Reach Existing Length Approach Proposed Len th Mitigation Ratio Proposed Credit 4% WQ Monitoring NTR1 303 R 326 1:1 326.00 13.04 NTR2 103 El 103 1.51 68.67 2.75 UTAR1 505 R 523 1:1 523.00 20.92 UTAR2 100 El 100 1.5:1 66.67 2.67 UTB 529 El 529 1.51 352.67 14.11 MCR1 1462 El 1462 1.5:1 974.67 38.99 MCR2 553 R 533 1:1 533.00 21.32 TOTAL 3555 3576 2844.68 113.80 W-1 1.323 E 1.320 2:1 0.660 0 EXAMPLE Project Risks and Uncertainties Listed below are identified project risks and uncertainties that have been evaluated in the development of design plans for the site, along with methods that have been/will be used to address these concerns. Methods to address may be presented as adaptive management. 1. Land use development: There is potential for increased land development around the site in the future that could lead to additional runoff and changes to watershed hydrology. Methods to Address: The project area has seen little development in recent years and it is unlikely that development will threaten the site in the foreseeable future. Restoration of the site to reconnect streams to their floodplains will reduce the likelihood of future degradation from watershed changes, as increased flows will spread over a wider floodplain. Grade control (in the form of constructed in -stream structures and natural bedrock outcrops) will decrease the chances of future channel incision. 2. Easement Encroachment: Any encroachment to the conservation easement. (Including road widening, culvert maintenance, utility easements, etc.) Methods to Address: The sponsor has had considerable discussions with the landowner regarding the project requirements and limitations of easement access and is confident that the landowner fully understands and will maintain the easement protections. The easement boundaries will be fenced with barbed wire fencing and clearly marked per NRCS standards. Any encroachments that do occur will be remedied by the sponsor to address any damage and provide any other corrections required by the IRT. 3. Drought and Floods: There is potential for extreme climatic conditions during the monitoring period of the project. • Methods to Address: The sponsor will apply adaptive management techniques as necessary to meet the site performance criteria. Such adaptive management may include replanting, channel damage repair, irrigation, or other methods. If adaptive management activities are significant, additional monitoring may be required by the IRT. 4. Beavers: While there was no evidence of recent beaver activity during recent assessments, there is potential for beavers to colonize the site during the monitoring period of the project. • Methods to Address: Due to the watershed size, beaver colonization is unlikely. However, the sponsor will take steps to trap and remove beaver if they colonize the Site during the monitoring period. 5. Hydrologic Trespass: There is potential for the stream restoration to create conditions under which hydrologic trespass on adjoining landowners is more likely. • Methods to Address: The majority of the project has been designed and will be constructed utilizing a priority 2 restoration approach, which will greatly reduce the potential of hydrologic trespass outside of the conservation easement boundary. Along UT1 Reach 3 where the stream transitions to a priority 1 restoration approach, the conservation easement boundary is located up the adjacent hill slopes. The ground elevations along the conservation easement boundary in this area are approximately 2 to 3 feet above the bankfull elevation. Based on Manning's equation, the cross section from easement boundary to easement boundary along UT1 Reach 3 will convey approximately 689 cubic feet per second (cfs). Using USGS regression equations, which utilize drainage areas and impervious surface, the estimated discharge from the 500-year recurrence interval is 185 cfs. Based off this information, the possibility of hydrologic trespass is extremely unlikely and is not expected to be an issue. 6. Invasive/Nuisance Species: Numerous invasives, such as kudzu and Chinese privet currently exist in the easement area. There is potential for these species to jeopardize buffer vegetation establishment. • Methods to Address: The sponsor will locate invasive vegetation. It will be visually assessed, photographed, and mapped. These areas will be treated by mechanical or chemical methods, so that invasive species are no more than 5% of the easement acreage, and zero tolerance for kudzu. Any vegetation requiring herbicide application will be performed in accordance with NC Department of Agriculture rules and regulations. EXAMPLE Adaptive Management An integral part of a successful compensatory mitigation project is early detection of problems during implementation, determining the cause(s) of those problems, and attempting to correct those problems so that the compensatory mitigation project achieves its objectives and ecological performance standards. Interim performance standards are crucial to ensuring compensatory mitigation performance follows a trajectory to attain final compensatory mitigation success. In the event the mitigation site or a specific component of the mitigation site fails to achieve the necessary performance standards as specified in the mitigation plan, the sponsor shall notify the members of the IRT and work with the IRT to develop contingency plans and remedial actions. Large scale corrective measures may require an Adaptive Management Plan. Large scale corrective measures may include, but are not limited to, re -grading part of the mitigation site, replanting more than 20% of the site to improve composition or species diversity, or the addition of stabilization structures. The Adaptive Management Plan review will follow Section 332.8(o)(9) of the 2008 Mitigation Rule, part of the streamlined review process, which requires an IRT review period of 15 calendar days. Once the Adaptive Management plan is prepared, the sponsor will: 1. Notify the USACE as required by the Nationwide Permit 27 general conditions. 2. Notify NCDWR if necessary for 401 conditions. 3. Revise performance standards, maintenance requirements, and monitoring requirements as necessary. 4. Obtain other permits as necessary. 5. Submit the Adaptive Management Plan for IRT review and approval. 6. Implement the Adaptive Management Plan. 7. Provide the IRT a Record Drawing/As-Built of corrective actions. The Final Mitigation Plan should include: 1. Identify responsible parties who will identify problems. 2. Potential problems that may arise during the monitoring period, particularly if performance standards are not met. 3. Potential causes of those problems. 4. Identify a process for determining measures to correct deficiencies in compensatory mitigation projects, such as site modifications, design changes, revisions to maintenance requirements, and revisions to monitoring requirements (see 33 CFR § 332.7(c)(3)) DEPARTMENT OF THE ARMY WILMINGTON DISTRICT, CORPS OF ENGINEERS 69 DARLINGTON AVENUE WILMINGTON, NORTH CAROLINA 28403-1343 REPLY TO ATTENTION OF: CESAW-RG/Browning MEMORANDUM FOR RECORD March 27, 2020 SUBJECT: Millstone Creek Mitigation Site - NCIRT Comments during 30-day Mitigation Plan Review PURPOSE: The comments listed below were received during 30-day comment period in accordance with Section 332.8(g) of the 2008 Mitigation Rule in response to the Notice of NCDMS Mitigation Plan Review. NCDMS Project Name: Millstone Creek Mitigation Site, Randolph County, NC USACE AID#: SAW-2019-01363 NCDMS #: 204 30- Day Comment Deadline: March 7, 2020 DWR Comments, Mac Haupt & Erin Davis: 1. Page 7, Table 1.1 — The 1:1 ratio proposed for NT R2, UTA R2 and UTB do not appear appropriate for the outlined E1 level approaches. However, DWR appreciates that proactive enhancement activities, such as cattle exclusion, have been implemented and are contributing to functional uplift. DWR would support a 1.5:1 ratio for the three proposed E1 / R equivalent reaches. DMS has revised the proposed mitigation for these reaches, per IRT input during the 4/24/2020 Millstone Mitigation Plan meeting, to restoration with a 1:1 credit ratio based on work proposed, 2. Page 28, Section 5.1 — The USFWS website was consulted on August 27, 2007. Please revisit this source to confirm that there have been no changes to listed species. The USFWS website was consulted on 3/30/2020; there have been no changes to listed species; this section of the plan has been updated with current information. 3. Page 35, Section 8.2 — Should Header be labeled as UTA R1 instead of UTA R2? This was mislabeled and has been fixed. 4. Page 36, Section 8.2.1 — DWR is concerned that by raising the channel bed by 5-6 feet at the top of UTA R1 and NT R1 that flow may not be maintained, and jurisdictional stream status may be lost. Flow documentation in the upper sections of these reaches will be critical. Surface gauges have been included in the monitoring plan to address this concern. 5. Page 39, Section 8.2.4 — Please correct UTA R2 and UT R2 to UTA R1. This comment has been addressed. 6. Page 48, Table 8.9 — Are live stakes included in the stem counts (e.g. silky dogwood)? If not, please include live stake species and estimated quantities. The revised document specifies live stake quantities in Section 8.6 Re -Vegetation Plan, Table 8.9. 7. Page 52, Section 8.7 — Are sod mats still being proposed? They do not appear in the design sheets. If proposed, please add a typical detail. Sod mats are proposed as an option in Section 8.7 of the revised Mitigation Plan, detail on page 6.1 of the plan sheets. 8. Page 53, Section 8.9 #3 — The proposed transition from perennial single thread channel to wetland will be an area to monitor for signs of instability. Additionally, with the wetland ditch plugged and the previously proposed log -step outfall not included in this design version, monitoring any concentrated flow areas developing between the wetland and Mill Creek for instability will also be important to address. The existing transition from single thread to wetland at the bottom of Ut B is currently stable due to very low gradient at the bottom of Ut B, the design will not cause instability. The transition between the wetland and Millstone Creek will be visually assessed twice annually throughout the monitoring phase of the project; the lack of excessive erosion or scour on the current ditch indicates a low energy system. 9. Page 56, Section 9.5 — The proposed wetland enhancement is based on hydrologic functional uplift, as such DWR recommends the hydrologic performance criteria of a minimum 8 percent hydro period. DWR also requests an additional wetland groundwater gauge, for a total of two wetland monitoring gauges. A hydrological performance standard of 8% along with an additional groundwater gauge has been included in the revised mitigation plan. 10. Page 56, Section 10 — Please confirm that the record drawings and baseline monitoring report will be submitted after completion of Phase 2 construction. Phased monitoring periods are not proposed, correct? Phased monitoring is required for the paired watershed study to document efficacy of RSC as designed. Record drawings will need to be completed on phase I project components upon completion of construction and planting. A complete record drawing and baseline monitoring report including phase I and phase II project components will be submitted for IRT review when both phases have been completed. The required seven-year monitoring phase will begin after the finalization of the baseline monitoring report. 11. Design Sheets - Please include the following items: a. Location of existing and proposed fencing; The fencing component of this project has been completed; DMS funded the design and installation of the easement fencing. Construction access will require small areas of existing fencing to be removed and replaced. The existing and proposed locations of fencing have been included on design sheets. b. Details: ford crossing, BMP wetland feature, ditch plug (specify minimum plug width), ditch filling/partial filling (specify maximum depth from ground surface to be filled), live stake installation, bare root and container planting Details have been included for the ford crossing, BMP wetlands, ditch (to include plug and fill specifications) and plant installation. 12. Figure 10.1 a. In order to monitor the minimum 30-day consecutive flow performance standard, please add flow gauges to NT R1 and UTA R1, within the upper one-third of each reach. Gauges have been included in these locations on the monitoring map. b. DWR requests an additional cross section along the lower section of MC R1 and an additional wetland groundwater gauge. An additional cross section has been added in this area. c. Please show the easement boundaries. The easement boundary has been included on maps and plan sheets. USACE Comments, Kim Browning: 1. When submitting the PCN, please include an estimate of the number of trees, or acres, to be cleared for the NLEB 4(d) Rule. The PCN will include the requested information. 2. Please QA/QC this document for grammar and typos. The revised document has been reviewed. 3. There is conflicting information throughout the plan: Page 12 states that Millstone Creek is the only perennial channel on site, while pages 22 and 39 indicate that all channels are perennial. Page 31 states that tributaries have little to no flow. NCSAM forms indicate channels are perennial. Please adjust the text for consistency. The revised mitigation plan clarifies that all project reaches are currently perennial; however, UTA R1 and NT R1 were likely intermittent prior to historic land conversion. UTA R1 and NT R1 are anticipated to be intermittent post construction. 4. Table 1.1: a The 2016 NCIRT Guidance specifies that additional credit of up to 2% may be generated for each tributary to be monitored for water quality. At a minimum, water quality and macroinvertebrate sampling must be conducted to receive the additional credit. Additional credit is eligible on restored and enhanced reaches of stream channels with the intent of linking stream mitigation and functional uplift. The IRT will authorize 4% additional credits for streams only on this site. The credit ratios proposed have been revised to reflect a 4% credit increase on stream reaches subject to water quality monitoring only. b. Water Quality credits are not authorized for wetlands. No Water Quality credits have been proposed on wetland in the revised mitigation document. c. The 2% increase proposed for success on At -Risk Tribs is not authorized. This request has been modified to include a success metric to address IRT comment during 4/24/20 meeting. A 20% Total-N reduction on stream reaches subject to water quality monitoring as compared to baseline Total-N is proposed. d. Please carry out stream credits to at least two decimal places, and avoid rounding. All stream credits have been to two decimal places. e. Please show how the credits are being calculated by reach length, total credits, and 4% increase per reach. For example, Reach NTR1 is proposed for 326 LF (existing 303 LF), 326 SMUs, and 13.04 additional credits at 4%. Please see example revision at the end of this document. The project asset table has been revised to follow the requested format. 5. Reaches proposed for El with a R Equivalent should be credited at 1.5:1, not 1:1 as proposed. The proposed work appears to be standard Enhancement I, defined as any stream mitigation activity that does not involve restoration of the entire stream channel. The only section that appears to meet restoration activities is on UTB near the bend at station 16+00. Additional credit for WQ monitoring is already being awarded on these reaches, and therefore is not justification for a 1:1 ratio. Bank grading, in -stream structures, and buffer planting meets the criteria for El at 1.5:1. Additionally, NTR1 is already receiving a 1:1 ratio, and the WQ treatment on that reach is not justification to increase the ratio on other reaches. Since cattle are currently excluded from project reaches, that is not justification for an increased ratio. The restoration level and ratios have been revised for these reaches to reflect work proposed and completed. This approach was discussed at the 4/24/2020 Millstone Meeting where previously undisclosed pertinent information such as DMS having funded the design and construction of the cattle exclusion fencing was clarified. 6. Categorical Exclusion Documents should be updated. The response letter from SHPO dated December 12, 2003 is sufficient. However, please update the NCWRC and USFWS documents. with current T&E species. I did receive an email response to the Public Notice from FWS on Aug. 13, 2019 stating that they have no significant concerns with this project. These documents have been updated as requested and appear in Appendix E of the revised mitigation plan. 7. Page 32: Is there a WQ monitoring station downstream of the ford crossing? The only water quality monitoring station to be located downstream of the crossing is a macroinvertebrate sampling location; a gauge to document overbank events will also be located on this reach. 8. Table 7.1 indicates that livestock exclusion fencing will be installed. It is unclear where fencing currently exists. Please indicate on a map or in the plan sheets. The plans sheets have been updated to include existing livestock exclusion fencing. The only additions/changes to the existing fencing installed by NC DMS are along the single ford crossing on Millstone, areas where existing fencing will be removed and replaced to allow for construction access and on terminal project boundaries across Millstone Creek. 9. Please include the water quality monitoring locations on the Monitoring Map. Water quality monitoring stations have been included in figure 10.2 Supplemental Monitoring Map. 10. Wetland enhancement area should demonstrate functional uplift. The performance standard for the wetland should be a minimum of an 8% hydro period, and pre -well data should be provided in order to show uplift. Additionally, a discussion of the NCSAM functional assessment rating as LOW for habitat might be helpful. An 8% hydrology performance standard has been included in the revised mitigation plan, all existing wetland data has been included in Appendix E, and a pre -construction gauge will be installed in the wetland. The NC WAM rating has been included in Section 3.2.5 Wetland 1 discussion. a Please add a vegetation monitoring plot to the wetland area to ensure that with increased hydrology the vegetation is not negatively impacted. A vegetation monitoring plot has been included in the wetland. The wetland is not to be planted per IRT guidance. 11. Please address how fescue will be treated/removed. Fescue has been addressed in Section 8.6. Re -Vegetation plan; fescue will be treated with herbicide prior to planting. 12. It appears that the majority of the site has buffer widths that exceed the minimum 50 feet. Since there is only one crossing on the site and you are capturing the terminal ends of the tributaries, you may want to consider running the Buffer Tool on the project to see if you can get the additional 2% buffer credit. The crossing and the wetland area will need to be clipped from the buffered area for credit. If it turns out to be beneficial, please include the GIS map and corresponding table. 13. Design sheets: Several sheets are upside down and out of order, and there are three sheets labeled page 4.5. Please correct. The document has been corrected. a Please include a ditch plug detail. A ditch plug detail has been included in the plan sheets. 14. There is concern for hydrologic trespass to occur since the ditch entering the wetland will be plugged and there is no planned outlet for the wetland. Site topography limits hydrologic trespass potential to the southern easement boundary. The site will be monitored for hydrologic trespass on the southern boundary of the easement between phase 1 phase 2 of the project and if necessary a remediation plan will be developed and implemented during phase 2. 15. Page 39, Section 8.2.4: Please QA/QC this paragraph for stream labeling. Also, to be clear about phased construction over a two-year period, the initial credit release will not occur until the Record Drawing/As-Built is received and approved. Stream labeling has been corrected. Millstone Creek is not subject to annual credit release due to date of project institution. 16. Ford Crossing: There is some concern with the amount of sediment coming into the system. Without seeing the design detail it's difficult to discern whether the structure will have an upstream and downstream sill to hold elevation and retain substrate in place. Will it be designed to incorporate reinforcing underlying material? Sediment load has been considered in the design for the project, both on and off -site sources are being addressed. A ford detail has been included in the plan sheets. 17. Page 53, #1: with the amount of sediment coming into the system, is there a concern that the pools will fill in over time, decreasing bedform diversity? The pools as designed contain log and boulder structures which mimic the functioning pools located upstream and downstream of the project reach. A note to address this has been included in the risk/ uncertainties section of the revised mitigation plan. 18. Beaver were mentioned in the document, please add this to the Risks/Uncertainties section. A discussion about effects of future beaver colonization has been added to the risks/ uncertainties section. 19. Page 54, Section 9: Please remove the statement "If all performance standards have been successfully met, NCDMS may propose to terminate stream, wetland and/or veg monitoring after MY5." 7 years of monitoring is required. This statement has been removed. 20. Section 9.4: There will be no loss of credits if this performance standard is not met; however, the additional 2% for NTR1, NTR2, UTAR1 and UTB are not approved. DMS has revised the proposal based on IRT input to include a measurable metric for the additional 2% credit proposed on water quality monitoring reaches. 21. Table 10.1: The section that discusses exclusion of livestock from channels is unclear whether fencing is existing or planned. The treatment for this section should be to install or maintain livestock exclusionary fencing. The discussion of the conservation easement establishment should be under site protection. The document has been revised to clarify that fencing had been previously installed by DMS. 22. Section 10.4: Please see the end of the document for example phrasing for the Adaptive Management section. The document has been revised to include an adapted version of the example provided. 23. Section 11: Please revise based on correct ratios. The document has been revised as requested. 24. General note: It's helpful when all maps and figures are located in one section of the plan. Example of how to revise Table 1.1: Reach Existing Length Approach Proposed Length Mitigation Ratio Proposed Credit 4% WQ Monitoring NTR1 303 R 326 1:1 326.00 13.04 NTR2 103 El 103 1.5:1 68.67 2.75 UTAR1 505 R 523 1:1 523.00 20.92 UTAR2 100 El 100 1.5:1 66.67 2.67 UTB 529 El 529 1.5:1 352.67 14.11 MCR1 1462 El 1462 1.5:1 974.67 38.99 MCR2 553 R 533 1:1 533.00 21.32 TOTAL 3555 3576 2844.68 113.80 W-1 1.323 E 1.320 2:1 0.660 0 EXAMPLE Project Risks and Uncertainties Listed below are identified project risks and uncertainties that have been evaluated in the development of design plans for the site, along with methods that have been/will be used to address these concerns. Methods to address may be presented as adaptive management. 1. Land use development: There is potential for increased land development around the site in the future that could lead to additional runoff and changes to watershed hydrology. • Methods to Address: The project area has seen little development in recent years and it is unlikely that development will threaten the site in the foreseeable future. Restoration of the site to reconnect streams to their floodplains will reduce the likelihood of future degradation from watershed changes, as increased flows will spread over a wider floodplain. Grade control (in the form of constructed in -stream structures and natural bedrock outcrops) will decrease the chances of future channel incision. 2. Easement Encroachment: Any encroachment to the conservation easement. (Including road widening, culvert maintenance, utility easements, etc.) Methods to Address: The sponsor has had considerable discussions with the landowner regarding the project requirements and limitations of easement access and is confident that the landowner fully understands and will maintain the easement protections. The easement boundaries will be fenced with barbed wire fencing and clearly marked per NRCS standards. Any encroachments that do occur will be remedied by the sponsor to address any damage and provide any other corrections required by the IRT. 3. Drought and Floods: There is potential for extreme climatic conditions during the monitoring period of the project. • Methods to Address: The sponsor will apply adaptive management techniques as necessary to meet the site performance criteria. Such adaptive management mayinclude replanting, channel damage repair, irrigation, or other methods. If adaptive management activities are significant, additional monitoring may be required by the IRT. 4. Beavers: While there was no evidence of recent beaver activity during recent assessments, there is potential for beavers to colonize the site during the monitoring period of theproject. • Methods to Address: Due to the watershed size, beaver colonization is unlikely. However, the sponsor will take steps to trap and remove beaver if they colonize the Site during the monitoring period. 5. Hydrologic Trespass: There is potential for the stream restoration to create conditions under which hydrologic trespass on adjoining landowners is more likely. • Methods to Address: The majority of the project has been designed and will be constructed utilizing a priority 2 restoration approach, which will greatly reduce the potential of hydrologic trespass outside of the conservation easement boundary. Along UT1 Reach 3 where the stream transitions to a priority 1 restoration approach, the conservation easement boundary is located up the adjacent hill slopes. The ground elevations along the conservation easement boundary in this area are approximately 2 to 3 feet above the bankfull elevation. Based on Manning's equation, the cross section from easement boundary to easement boundary along UT1 Reach 3 will convey approximately 689 cubic feet per second (cfs). Using USGS regression equations, which utilize drainage areas and impervious surface, the estimated discharge from the 500-year recurrence interval is 185 cfs. Based off this information, the possibility of hydrologic trespass is extremely unlikely and is not expected to be an issue. 6. Invasive/Nuisance Species: Numerous invasives, such as kudzu and Chinese privet currently exist in the easement area. There is potential for these species to jeopardize buffer vegetation establishment. • Methods to Address: The sponsor will locate invasive vegetation. It will be visually assessed, photographed, and mapped. These areas will be treated by mechanical or chemical methods, so that invasive species are no more than 5% of the easement acreage, and zero tolerance for kudzu. Any vegetation requiring herbicide application will be performed in accordance with NC Department of Agriculture rules and regulations. EXAMPLE Adaptive Management An integral part of a successful compensatory mitigation project is early detection of problems during implementation, determining the cause(s) of those problems, and attempting to correct those problems so that the compensatory mitigation project achieves its objectives and ecological performance standards. Interim performance standards are crucial to ensuring compensatory mitigation performance follows a trajectory to attain final compensatory mitigation success. In the event the mitigation site or a specific component of the mitigation site fails to achieve the necessary performance standards as specified in the mitigation plan, the sponsor shall notify the members of the IRT and work with the IRT to develop contingency plans and remedial actions. Large scale corrective measures may require an Adaptive Management Plan. Large scale corrective measures may include, but are not limited to, re -grading part of the mitigation site, replanting more than 20% of the site to improve composition or species diversity, or the addition of stabilization structures. The Adaptive Management Plan review will follow Section 332.8(o)(9) of the 2008 Mitigation Rule, part of the streamlined review process, which requires an IRT review period of 15 calendar days. Once the Adaptive Management plan is prepared, the sponsor will: 1. Notify the USACE as required by the Nationwide Permit 27 general conditions. 2. Notify NCDWR if necessary for 401 conditions. 3. Revise performance standards, maintenance requirements, and monitoring requirementsas necessary. 4. Obtain other permits as necessary. 5. Submit the Adaptive Management Plan for IRT review and approval. 6. Implement the Adaptive Management Plan. 7. Provide the IRT a Record Drawing/As-Built of corrective actions. The Final Mitigation Plan should include: 1. Identify responsible parties who will identify problems. 2. Potential problems that may arise during the monitoring period, particularly if performance standards are not met. 3. Potential causes of those problems. 4. Identify a process for determining measures to correct deficiencies in compensatory mitigation projects, such as site modifications, design changes, revisions to maintenance requirements, and revisions to monitoring requirements (see 33 CFR § 332.7(c)(3))