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HomeMy WebLinkAbout20230094 Ver 1_More Info Received_20230515 (2)Additional Information C.4a. Describe the existing conditions on the site and the general land use in the vicinity of the project at the time of this application. The proposed project extends from Avents Ferry Road to Poplar Springs Church Road in Lee County, North Carolina. The proposed project involves construction of a new pump station, directly adjacent to the existing Sanford Raw Water Pump Station, to support intake capacity upgrades of 30 million gallons per day (MGD). The existing pump station will be demolished, rebuilt in place, and repurposed for equipment storage. Additional upgrades include a new raw water intake structure within the Cape Fear River, an influent line from the intake to the new pump station, and an upgraded raw water line from the new pump station to the existing Water Filtration Facility (WFF) located on Poplar Springs Church Road, southwest of the existing pump station site. Installation of the proposed conveyance line will parallel an existing easement owned and maintained by Enterprise Products, immediately north of the project site. The project site is currently surrounded by undeveloped, forested areas to the north, south, and west. Beyond which, to the north, along Lower River Road, are low density residential housing developments. An existing pump station is located adjacent to the Cape Fear River, abutting Avents Ferry Road. The existing intake associated with the current pump station extends approximately 57-feet into the Cape Fear River. C.4h. Explain the purpose of the proposed project Replacement of the existing pump station, intake, and conveyance line are necessary to meet the demands of projected growth in Lee County and the surrounding area. Additionally, the existing intake is partially buried below the river mud line causing high levels of sediment ingestion. The proposed project consists of replacement of approximately 1.9 miles of 30-inch raw water conveyance line and abandonment of the existing conveyance line, and other related appurtenances per applicable regulations. Additional project components consist of demolishing the existing pump station to rebuild and repurpose for storage. A new pump station and its associated intake and influent line will be built adjacent to the existing pump station to support intake capacity upgrades of 30 MGD. C.4i. Describe the overall project in detail, including indirect impacts and the type of equipment to be use. The project consists of installation of approximately 1.9 miles of a 30-inch raw water main from the existing Sanford Water Filtration Facility to the proposed pump station located off Avents Ferry Road, adjacent to the Cape Fear River. An existing pump station, located off Avents Ferry Road, will be demolished, rebuilt in place, and repurposed for storage. The intake structure associated with the existing pump station will be removed and its associated raw water line will be disconnected and sealed. A new pump station is proposed off Avents Ferry Road, adjacent to the existing pump station to expand intake capacity. The new pump station will include construction of a retaining wall, a new intake structure, and a new raw water influent line joining the pump station to the intake structure. The new intake structure will extend approximately 185-feet into the Cape Fear River. Erosion and sediment control measures will be installed prior to commencing land -disturbing activities. The proposed project's limits of disturbance encompass approximately 15 acres in total. CGIRS46IGtieR phase access te the preject will be pFeVid_cd_ Via _AA eXiStiRg picejee_# eA_.rr*cA_.r with the picepesed PUMP StatieR, Will be used for r-AA1#P1 Gtec)n phase access and pest GeRStFWGti 0 s asseceated with aR engeiRg prejeet that wall be permitted, mitigated, and installed by etheFs PFieF tE) access is picevided the a Construction -phase access to the project will be provided via temporary construction entrances. One temporary construction entrance off Poplar Springs Church Road will be installed for construction phase access and will have no impacts to jurisdictional waters. Following installation of the proposed pipe at S1, the pump around system will be removed and a temporary stream crossing will be installed to provide construction access to northeast areas of the project. An additional temporary construction entrance will be provided via swamp mats at W3, adjacent to the existing pump station off Avents Ferry Road. Additional details related to proposed construction -phase access is provided in the attached design drawings. Installation of the transmission line in jurisdictional areas (wetlands and streams) will be achieved using open -cut techniques. Anti -seep collars will be installed along the transmission line per applicable regulations within jurisdictional wetlands. Crossing of the stream and wetlands by the raw water main will not result in the net loss of jurisdictional waters. Crossing of the streams and wetlands by the proposed pipe will not result in the net loss of jurisdictional waters of the U.S.; however, W1 will undergo conversion impacts from forested to non -forested. Conversion impacts will take place at W1 to ensure proper access for maintenance of the pipe following construction activities per applicable state regulations. Stream crossings will be performed within 15 degrees of perpendicular. Three jurisdictional wetland areas will be traversed by the project corridor accounting for 0.43 acre of temporary impacts. Permanent wetland impacts of 0.53 acre via conversion of forested to non -forested will take place at W1 and will be mitigated accordingly. Two perennial streams, the Cape Fear River and an unnamed stream, will also be traversed by the project corridor accounting for 0-.9-9 0.61 acre of temporary impacts and 0410.005 acre of permanent impacts. Permanent impacts within the Cape Fear River include a new intake structure screens. The proposed raw water influent line connecting the intake to the pump station will result in temporary impacts during construction. Construction associated with the existing pump station, proposed pump station, and proposed retaining wall will not result in impacts to jurisdictional waters as all work will take place in upland areas. impacts * ;,,,-isAi,.*; . al ,.r *1;4Ad'• will be temperaFy and Temporary impacts to jurisdictional wetlands will include limits of disturbance during construction activities as well as open -cut installation of a 30-inch raw water main. Fully biodegradable rolled erosion control matting may be used for surface stabilization in W3, adjacent to the proposed pump station, resulting in temporary impacts to no more than 0.05 acre. All stream work, including pipe installation and installation of the new intake structure, will be done in the dry and no live concrete shall come in contact with jurisdictional waters. During construction activities, a temporary coffer dam wv 4may be placed upstream and downstream of the area of disturbance and the stream will be pumped around the dammed area. Following installation of the coffer dam, hydrology from W3 will be routed to the Cape Fear River using a pump around system. During construction, any additional dewatering necessary from potential storm events will be left to the contractor to design and implement. The contractor will be required to follow all applicable requirements and obtain any necessary approvals. ` lhmle the coffer .Jaw. n,-,,. ent the h.,dFe'E)gy If deemed feasible by the contractor, installation of the new intake and its associated waterline, as well as demolition of the existing intake, will be completed via trained divers. Utilization of divers to perform in stream construction efforts reduces the necessary footprint of the cofferdam during construction. A turbidity curtain will be used in place of a coffer dam, not to exceed the limits provided for the coffer dam on the attached design plans. If divers are used, any concrete associated with the proposed intake will be constructed from upland areas and allowed to dry prior to installation in the Cape Fear. No permanent fords will be installed at the stream crossing; however, a temporary stream crossing will be utilized at S1. The temporary stream crossing will not have impacts to jurisdictional waters as it will expand from top of bank to top of bank. For additional details related to the temporary stream crossing, please refer to sheet PPD6 of the attached design drawings. Equipment anticipated to be used during installation of the proposed transmission line includes, but is not limited to, excavators, backhoes, front-end loaders, dump trucks, and cranes. Details of proposed activities, such as temporary stream bypass structures and anti -seep collars, are provided on the design drawings submitted in conjunction with this permit application. Indirect impacts associated with installation of the influent conveyance and intake structure are anticipated to be negligible since construction of the proposed project will not induce growth but is required to meet toe current and future demands of the service area. D. 2i. Wetland Impacts Comments During onsite delineation efforts, W1 was identified as palustrine forested. W1, as depicted on the attached Delineation Impact Map 2, will be permanently converted from a forested to non -forested wetland to ensure proper maintenance of the pipe corridor following construction. At current, W2 and W3 are palustrine emergent wetlands; therefore, no conversion impacts are necessary. The permanent maintenance corridor throughout the proposed project site is 45-feet; however, 40-feet is proposed in all wetland areas to minimize impacts to the extent feasible. E.1a. Specifically describe measures taken to avoid or minimize the proposed impacts in designing the project. Delineation of jurisdictional areas and identification of sensitive receptors occurred early in the design process. During design, the project corridor was positioned to avoid regulated areas and sensitive receptors, where feasible, while using existing corridors and easements to the extent practicable. g di e: Although the permit status of Project Blue is unknown, coordination took place with Freese & Nichols to ensure mitigation of onsite wetlands were not duplicative for the City of Sanford. Mitigative measures relative to a permanent maintenance corridor associated with W1 will be purchased prior to construction commencement by either Hazen or Freese and Nichols. Avoidance of all impacts is possible only with a no -build alternative, which does not meet the need of the project. Where avoidance of jurisdictional wetlands was not possible, the limits of disturbance were reduced to the extent practicable. Installation of the new raw water intake and removal of the existing raw water intake cannot be completed without in -water work. Project design includes anti -seep collars along the pipe within and adjacent to jurisdictional wetland areas, per applicable requirements. Avoidance of the streams within the project corridor is not feasible. Stream crossings were designed to minimize the limits of disturbance with crossings within 15 degrees of perpendicular, where feasible. A temporary stream crossing will be utilized at S1. The temporary stream crossing will not have impacts to jurisdictional waters as the dragline bridgemat will expand from top of bank to top of bank. Swamp mats will be used to cross jurisdictional wetlands to minimize impacts from vehicular crossings. E.1b. Specifically describe measures taken to avoid or minimize the proposed impacts through construction techniques. Best management practices for erosion and sediment control measures are specified in the project design. Measures include perimeter silt fence, minimization of tree removal, and stabilized construction entrances. The contractor shall perform weekly inspections of erosion and sediment control devices and perform maintenance as needed to ensure maximum efficacy of all devices in use. Vehicle and equipment maintenance activities are required to be performed outside of jurisdictional areas. Disturbed soils will be temporarily stabilized if the disturbed area will not be final graded and permanently stabilized within a reasonable timeframe. Impacts to jurisdictional areas during construction will be limited to the extent feasible by performing as much work as is possible from upland areas. Disturbed areas, including temporary wetland and stream impacts, will be returned to original grade and seeded with an appropriate native seed mix as soon as possible, not to exceed 90 days of completion of the project. In wetlands, the contractor shall remove and stockpile the top 12" of material. The stockpiled material shall be used to backfill the top 12" of the trench in wetlands during backfill operations. Trenches will be constructed and backfilled per applicable regulations to ensure waters of the U.S. are not subject to drainage during construction activities. Please refer the erosion control section on sheet C001 of the attached design plans for additional details relative to the restoration of temporarily disturbed wetland areas following construction. Swamp matting will be used where appropriate in wetland areas. Excavation of the pipe trench will be performed as prescribed by the USACE in jurisdictional areas, and side casting of excavated material into abutting wetland areas will be avoided to the extent feasible. Assessment of alternative methods versus using open -cut installation was performed. Most of the areas of disturbance within jurisdictional features are either very small or are in areas that are already disturbed, such as abutting existing maintained transmission corridors. Due to the small size of the areas of disturbance and the existing disturbed condition within jurisdictional areas, use of trenchless installation techniques will not be used to traverse jurisdictional wetland areas or the perennial stream abutting Lower River Road. Installation techniques associated with the new raw water intake line in the Cape Fear River will be at the contractor's discretion. Directional drilling will be utilized where feasible to limit disturbance and will adhere to applicable regulations; however, the contractor may use open -cut techniques as deemed fit. In the event that directional drilling takes place, the contractor will be provided a frac-out detail which can be found in the attached design drawings for reference. G.3b. If you answered "no", provide a short narrative description. Development within the Sanford WFF service area is anticipated to occur. The proposed project will not promote growth but will support the development that will occur regardless of the project and will provide state of the art municipal treatment of drinking water. Existing ordinances and regulations, including the Clean Water Act, erosion and sediment control regulations, and stormwater ordinances, are expected to prevent impacts to downstream water quality due to future development in the pump station's service area. G.Sj. Endangered species within project area. Hazen biologists reviewed the FWS online IPaC tool to determine species and/or critical habitat within the vicinity of the proposed project on October 3, 2022 and December 14, 2022. The proposed project is not located within range of critical habitat for any federally listed species. Onsite field investigations were conducted by Hazen staff in October 2022 and no evidence of federally listed species was observed. Additional field surveys were conducted on December 12, 2022 to investigate for presence and/or absence of the red cockaded woodpecker (Picoides borealis). No evidence of red cockaded woodpeckers or their preferred habitat, in the form of mature pines, were observed within the project's vicinity. Additionally, no cavities exuding sap were observed within the proposed project limits. G.7a. What data sources did you use to determine whether your site would impact historic or archeological resources? Hazen biologists reviewed HPOWEB on December 19, 2022 to determine potential impacts to historical or archeological resources. No historic districts have been documented in the National Register within the project's vicinity. At present, Memphis Methodist Church and Cemetery (Site ID LE0242) is shown on the National Register study list. No determinations have been made regarding the site. Memphis Methodist Church and Cemetery is located approximately 396-feet east of the proposed project site. The Methodist Church and Cemetery site will not be utilized for any construction activities related to the proposed project. At current, the 396-feet between the proposed project site and Memphis Methodist Church and Cemetery is undeveloped, providing a forested area as a buffer. At present, no additional structures are documented within, surrounding, or visible from the proposed project site. G.Bb. If yes, explain how project meets FEMA requirements. The proposed project is within a FEMA-designated 100-year floodplain according to North Carolina's FEMA GIS data reviewed by Hazen. An additional flood study within the proposed project's limits of disturbance will be necessary to determine if the project will result in a rise. The documentation required (i.e. County Floodplain Permit, conditional letter of map revisions, etc.) to build within a FEMA- designated 100-year floodplain will be acquired prior to construction.