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property boundaries, right-of-way, and easements will be provided based on available plat <br /> maps and record data. A formal boundary field survey will not be conducted. Finished floor <br /> elevations for identified houses will be collected for inclusion in evaluation of the floodplain <br /> limits. HDR will provide the COSM a map of identified houses for finished floor survey for <br /> concurrence prior to collecting data. Topographic data scope and fee can be seen in <br /> Attachment A. <br /> c. The City will provide HDR with the latest drainage design concepts proposed for the Mystic <br /> Canyon development located northwest of Castle Forest including stormwater detention pond <br /> characteristics to incorporate into the project hydrologic model. <br /> d. HDR will manage the utility identification and location of conflicting existing franchise utilities <br /> in the project area with the owner of each utility including requesting utility mapping. <br /> e. HDR will conduct on-site delineation survey of aquatic sites to document extent of potential <br /> waters of the U.S., including streams, excavated channels, and wetlands. The routine on-site <br /> delineation will be conducted in accordance with the U.S. Army Corps of Engineers (USACE) <br /> 1987 Wetland Delineation Manual and 2010 Great Plains Regional Supplements. <br /> f. HDR will prepare delineation report and proposed Jurisdictional Determination (JD) report <br /> summarizing the findings of the delineation of potential waters of the U.S. The proposed JD <br /> will be based on the pre-2015 rules currently in effect (i.e., Rapanos Guidance). <br /> g. HDR will perform evaluation of vegetation community types with the potential to serve as <br /> suitable habitat for Migratory Bird nesting areas. <br /> III. Texas Water Development Board(TWDB) Flood Infrastructure Fund(FIF) Environmental <br /> Documentation <br /> a. HDR will prepare and submit the Categorical Exclusion (CE)/Determination of No Effect <br /> Request Form for the COSM to submit to the TWDB for the FIF application. <br /> b. HDR will prepare and submit up to five agency letters on the proposed project with a <br /> description and map to get information for the TWDB environmental review. <br /> c. HDR will respond to up to two rounds of questions and/or requests for information from <br /> TWDB on the environmental documentation. <br /> IV. Update Hydrology and Hydraulic Models <br /> a. HDR will utilize drainage plans by others (provided by COSM)for the upstream development <br /> to verify offsite flows and re-configure pond size and outfall size using InfoWorks ICM (ICM). <br /> HDR will compare existing and proposed flows and utilize the proposed development plans to <br /> create the proposed conditions and make recommendations to modifications. <br /> b. HDR will update the ICM modeling developed during the PER including: <br /> L Update the proposed channel, storm drain, and detention pond design elements for <br /> the chosen alternative with new information from upstream development. <br /> ii. Update the model with survey data <br /> iii. Update the model with Atlas 14 data <br /> c. HDR will verify that the proposed model updates still address flooding as defined in the PER. <br /> d. HDR will verify proposed design does not increase flows or WSEL's downstream of the <br /> channel to the next confluence. <br /> e. HDR will make minor modifications (e.g., minor adjustment to manhole locations, pipe <br /> diameters, etc.)to the chosen alternative design if necessary to meet COSM criteria. If major <br /> revisions are required, HDR reserves the right to renegotiate the scope and fee. <br /> f. After updating the upstream detention pond configuration, HDR will evaluate the Alternative 2 <br /> design as outlined in the PER and add or remove design components as necessary, If <br /> additional flood mitigation infrastructure is added, the total OPCC must not exceed what is <br />