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2.7 Additional Excavation If additional excavation beyond the limits shown on Figures 4 and 5 is required due to the results of the initial confirmation sampling, the excavation work will be conducted immediately. The excavation will be extended in the direction of the compound detection to the practical limits of the excavation equipment or to within the lateral boundary as defined by the site investigation borehole locations. If detected underneath the building foundation, as much soil as ' practically possible will be removed. The excavated soil will be stored, sampled and disposed in the same manner as the soil excavated initially. The same ' equipment and site clean-up procedures will be used. After the additional soil is excavated, confirmation samples will be taken in a manner similar to the initial sampling described in Section 2.6 above for the area in which the extra excavation was conducted. If sampling from beneath the - building slab is required, samples will be obtained from soils collected in the excavation or backhoe bucket. Sample locations will be selected depending on the configuration and size of the newly excavated area. 2.8 Restoration ' Upon the determination that the confirmation soil samples contain concentrations less than 1.0 mg/kg of DBCP or if the compound presence extends beyond the practical boundaries of the excavation (i.e. underneath the building foundation), the excavation will be backfilled to achieve the original surface grade. ' The excavation will be backfilled with soil similar to the native soil in the area or with pea gravel. The backfill will be compacted to 93% Standard compaction to ' within two feet of the surface and 95% Standard compaction for the last twenty inches. A four inch layer of asphalt will be placed on top of the backfilled soil to ' match the existing site surface. s