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As conditioned, the trails would be accessible to pedestrians, equestrians, and bicyclists with the final determination made by the Parks and Recreation Commission with input from the Trails Ad-Hoc Committee in conjunction with their review of the detailed trail plans. Grading/Urban Stormwater Runoff Grading A preliminary grading plan is provided with Exhibit A. The proposed grading to be done with the subdivision would "cut" the top of the main ridge bisecting the site in order to accommodate the main access road from Hearst Drive, the individual courts, and a narrow area adjoining the roads corresponding to the front yards of the building sites, and to stockpile the spoil material on the two stockpile areas shown on the development plan. The proposed grading will result in a total of approximately 620,000 yards of cut and fill material. Of this amount, approximately 390,000 cubic ayards will be moved to the stockpile areas. The stockpile areas will be graded at a 3:1 slope with minimal "benches" and "V"-ditches to minimize the horizontal dimension of the stockpiles, thereby keeping the stockpile away from sensitive habitat areas. These stockpile areas would be for the subdivision grading only and would not be available for the surplus grading generated by the individual lot construction Minimal grading is done with the individual building sites and is limited to the lots' front yard areas with the remaining lot area retained as natural terrain. Individual lot grading would be reviewed with the building design applications. A key point of the building design guidelines is to "step" the building form based upon the site's contour to reduce the amount of individual cut and fill quantities. All graded areas would be re-contoured and re-vegetated in a manner designed to blend in with the natural appearance of the surroundings. Urban Stormwater Runoff A significant feature of this development is its stormwater runoff measures that will pretreat the runoff from the entire development before its entry into the City's stormdrain systems. To achieve this, the applicant will install three detention ponds to pretreat the development's storm water runoff before entering the site's existing drainage areas and/or the City's storm system. The detention ponds would be maintained by the Homeowners Association or by the GHAD. Stormwater runoff from the public street and all lots will be conveyed to the detention pond by a combination of "V"-ditches and/or by underground piping. The applicant's proposal is reflected on the development plan and in the draft conditions of approval. The development's storm water runoff measures will be shown in detail with the tentative subdivision map for review and approval by the Planning Commission. However, some lots because of their location will have to pre-treat their stormwater runoff on-site and then discharge it directly into an existing swale. PUD-33 Page 48 of 59 June 13, 2007