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remaining deposits on the lots' unimproved areas could experience future soil movement. However, the potential movement would be downslope and away from the improvements, such that the building pads and other upslope improvements would not be affected. The erosion hazard on the hill slopes is severe to very severe where water runoff is rapid. Soils underlying the project site have high shrink-swell potential, which could damage buildings and infrastructure if the potentially expansive soils are not considered in the project design and construction. Corrosive soils, if present, could dissolve or weaken underground utilities and structural components, such as metal and concrete. Mitigations Measures Mitigation measures for the above-described issues are addressed in the draft conditions of approval and include: The applicant is required to undertake a detailed, design-level geotechnical investigation and, based upon this investigation, to submit adesign-level geotechnical report with the tentative subdivision map application. This second evaluation and report is the engineering design report that will address the technical aspects of dragging, drainage, retaining walls, streets, etc. The report will be peer reviewed by a geotechnical consultant selected by the City. The recommendations specified in the report and by the peer review consultant will be incorporated into the development's grading and improvement plan designs for review and approval by the City Engineer before the Planning Commission's action on the tentative subdivision map. During the mass grading of the subdivision, the applicant shall arrange and pay for a geotechnical engineer, the selection subject to the approval of the City Engineer, to be present on-site at all times to inspect and approve all subdivision improvements and to prepare and submit progress reports to the City Engineer. This is considered to be standard City practice on the development of hillside properties in geologically sensitive areas. ^ The applicant is required to create a Geologic Hazard Abatement District (GRAD) for this development covering the public and private areas. The GRAD will administer an ongoing Slope Management Program over these areas, which will include periodic inspections and reports to the City on public land and to the Homeowners Association on private land. The applicant proposes that the GRAD assume the management responsibilities of some areas of the development -fire buffer areas, reforestation areas, etc. -that would otherwise be the responsibility of the Homeowners Association. Staff considers the applicant's request workable and has included this option -Homeowners Association or GRAD where applicable, and subject to the City Engineer's determination - in the draft conditions of approval. The determination would be made prior to the approval of the first final subdivision map. PUD-33 Page 36 of 59 June 13, 2007