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Appendix D <br />Standard Specifications for Grading <br />Page D-9 <br />Roof, pad and slope drainage should be directed away from slopes and areas of structures to <br />suitable disposal areas via non -erodible devices (i.e., gutters, downspouts, and concrete swales). <br />For drainage in extensively landscaped areas near structures, (i.e., within four feet) a minimum <br />of 5 percent gradient away from the structure should be maintained. Pad drainage of at least 2 <br />percent should be maintained over the remainder of the site. <br />Drainage patterns established at the time of fine grading should be maintained throughout the life <br />of the project. Property owners should be made aware that altering drainage patterns could be <br />detrimental to slope stability and foundation performance. <br />Section 10 - Slope Maintenance <br />10.1 - Landscape Plants <br />To enhance surficial slope stability, slope planting should be accomplished at the <br />completion of grading. Slope planting should consist of deep -rooting vegetation <br />requiring little watering. Plants native to the southern California area and plants relative <br />to native plants are generally desirable. Plants native to other semi -arid and and areas <br />may also be appropriate. A Landscape Architect should be the best party to consult <br />regarding actual types of plants and planting configuration. <br />10.2 - Irrigation <br />Irrigation pipes should be anchored to slope faces, not placed in trenches excavated into <br />slope faces. <br />Slope irrigation should be minimized. If automatic timing devices are utilized on <br />irrigation systems, provisions should be made for interrupting normal irrigation during <br />periods of rainfall. <br />10.3 - Repair <br />As a precautionary measure, plastic sheeting should be readily available, or kept on hand, <br />to protect all slope areas from saturation by periods of heavy or prolonged rainfall. This <br />measure is strongly recommended, beginning with the period prior to landscape planting. <br />If slope failures occur, the geotechnical consultant should be contacted for a field review <br />of site conditions and development of recommendations for evaluation and repair. <br />If slope failures occur as a result of exposure to period of heavy rainfall, the failure areas <br />and currently unaffected areas should be covered with plastic sheeting to protect against <br />additional saturation. <br />STANDARD SPECIFICATIONS OF GRADING <br />Page 9 of 26 <br />