PC-98-31 - Laserfiche WebLink

H7. The final geotechnical report for the grading plan for proposed projects within the Specific Plan Area shall be prepared by a professional engineer and approved by the City of Pleasanton. The report shall address the potential for delayed consolidation within deep fills and associated land sur- face subsidence. The report shall provide specific recommendations for: . Fill compaction specifications that consider the likelihood of eventual saturation and wetting and drying cycles for the fill materials; . Removal of colluvial material or weathered rock that may be subject to consolidation under the , load of proposed fills; , . Design that minimizes the variability of fill thickness within fills that underlie structures or other improvements at the project site; and . Design and operation of adequate subsurface drainage systems for fills (particularly beneath heavily irrigated areas or other water sources such as swimming pools or detention basins). Drainage systems for the fills shall be designed to minimize maintenance and ensure long-term performance. Flow from the drainage system shall be controlled so as not to cause or contrib- ute to erosion of existing drainage channels. Timing: Prior to approval of grading plans. H8. On expansive soils, building foundations and improvements shall consist of drilled pier and grade beams, deepened footings (extending below expansive soil), or post-tensioned slabs. Alterna- tively, expansive soil shall be removed and replaced with compacted non-expansive soil prior to foundation construction. The plan requires that sub grade soils for pavements consist of moisture- conditioned, lime-treated, or non-expansive soil, and that surface and subsurface water be directed away from foundation elements to minimize variations in soil moisture. Timing: Foundations and improvements to be specified in building plans prior to issuance of building permits. I. PUBLIC HEALTH AND SAFETY II. Complelion of a Phase I Environmental Site Assessment by a qualified environmental professional in accordance with the requirements of the American Society for Testing and Materials (ASlM, 1997) is required. Timing: Prior to approval of grading permits for the Golf Course and Spotorno properties. U. Completion of a Phase II Environmental Site Assessment is required if the findings of the Phase I Envi- ronmental Site Assessment indicate the presence of, or potential for, use of hazardous materials in ass0- ciation with current or historical land uses. The Phase II Assessment, to ascertain whether past or cur- rent land uses have contributed to soil and groundwater contamination at the site, must be conducted by a qualified environmental professional. Soil and groundwater samples collected during the Phase II Assessment shall be submitted to a Califomia-certified laboratory for analysis. Timing: Prior to approval of grading permits for the Golf Course and Spotorno properties. 15