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Significant Impact <br /> Impact 4.3-5: Project construction would require the filling of seasonal drainage channels and in-channel <br /> wetlands. <br /> Finding <br /> Changes or alterations have been required in, or incorporated into,the project which mitigate or avoid the <br /> significant effects on the environment. <br /> Facts in Support of Finding <br /> The City of Pleasanton has adopted the following measures which will reduce potential impacts to <br /> seasonal drainage channels and in-channel wetlands to a less-than-significant level: <br /> Mitigation Measure 4.3-5: The proposed project would impact approximately 0.022 acre of Waters of <br /> the United States(0.016 acre and 243 lineal feet of drainage channel waters,and 0.006 acre of in-channel <br /> wetlands). The connection to Sunset Creek Lane would require approximately 100 linear feet(400 square <br /> feet)of additional impact. While compensation for impacts to Waters of the United States shall occur at a <br /> minimum of a 1:1 replacement ratio,the CDFW and RWQCB generally require a replacement ratio of 2:1 <br /> or better. To the degree possible,the applicant shall replace lost wetland resources in kind. Thus,the <br /> project would create at least 343 feet of channel(1:1 ratio)and 0.031 acres of waters of the US (seasonal <br /> drainage channel), of which would be at least 0.006 acres of seasonal wetlands on the Lund Ranch <br /> property. Creation of new channels can be logistically difficult as there are finite areas within a site to <br /> accomplish this type of mitigation. Therefore, some mitigation for the seasonal channel may have to be <br /> out-of-kind. This could be accomplished by creating additional seasonal wetlands. The creation of not <br /> less than 0.031 acre of wetland and/or seasonal channel would be required. <br /> The site supports sufficient opportunities to accommodate creation of wetland habitat. Even if the project <br /> could not create 243 feet of channel,there are a number of areas along Drainage Areas A and B and <br /> within the non jurisdictional drainage swales on the site that could easily accommodate this type of <br /> constructed wetland mitigation. <br /> The goal of this mitigation should be to create new wetlands and enhance existing wetlands in a way that <br /> replaces the functions and values of the wetlands that are proposed to be filled. A qualified biologist <br /> should develop a restoration plan that identifies the full extent of the impact, location of suitable sites to <br /> create or enhance wetlands of the necessary acreage, and develop success criteria specific to the actual <br /> wetland creation design. The mitigation site should be monitored for at least five years. A detailed <br /> wetland restoration plan should be developed for this mitigation area during the regulatory permitting <br /> phase of the project. The plan will be subject to review by the City of Pleasanton and acquisition of the <br /> required permits through City consultation with the USACE, RWQCB, CDFW. This plan should <br /> incorporate additional studies and details, including the following: <br /> • Type and acreage of wetland to be impacted and goals for wetland creation <br /> • Detailed assessment of soil suitability for wetland creation <br /> • Description of site hydrology, including depth and duration of inundation, potential for scour or <br /> deposit of sediments, etc. <br /> • Site preparation measures, including grading methods,to relieve compaction and/or ensure low <br /> potential for scouring of soils <br /> • Revegetation and erosion control on slopes surrounding the mitigation site <br /> • Description of buffer areas around the mitigation <br /> • Maintenance program <br /> • Long term monitoring program, including performance and success criteria. <br /> LUND RANCH II(PUD-25)RESIDENTIAL PROJECT 9 FINDINGS <br />