Top of bedrock definition

Top of bedrock means the top of firm rock as deter- mined by a change in the action of the drilling machine or a change in the type and size of the drill cuttings. The presence of bedrock shall be indicated when a majority of the drill cuttings consist of either angular rock fragments, as in the case of crystalline bedrock, or rock fragments composed of individual grains or rock particles that are cemented together to form an aggregate, as opposed to single sediment particles, such as in sand.

Top of bedrock means the elevation of the bedrock surface at the location in question. If site-specific information is available, the site-specific information shall be utilized. Otherwise, regional map(s) of the top of bedrock approved by the Department shall be utilized.

Top of bedrock or “top of firm rock” means at least seventy percent (70%) of the drill cuttings being either:

Examples of Top of bedrock in a sentence

• The horizontal and vertical extent of contaminant plumes including the relative density and thickness of any separate phase liquids (SPL) present.• Top of bedrock contour (if encountered).A conceptual site model should be developed and refined as information is gathered during the site characterization.

• Top of bedrock was encountered in borings at depths ranging from 26 feet bgs near the southeastern end of Building 101 to 58 feet bgs near the southeastern end of Building104.

• Figure 9 – Top of bedrock maximum zinc plus lead values over the Toggenburg project area.

• Top of bedrock for the purpose of this Item will be where the cased hole pre-drilled through the overburden ends (see Item 944.2).

• Top of bedrock elevations in the Piedmont physiographic province vary considerably over short horizontal distances and, dependent on differential weathering and bedrock type, pinnacles of rock may be encountered above auger refusal depths.

• Top of bedrock in the vicinity of the project is estimated to be 300 to 400 feet below ground surface (Sweet-Edwards/EMCON 1991).

• Top of bedrock surface shown on Figure 3 is an average rock surface, localized high and low areas exist.

• Top of bedrock soil auger sampling completed at several sites previously sampled by shovel sampling indicate that past soil data may contain a significant proportion of false-negative values.

• Top of bedrock sampling by RAB drilling and deeper reverse circulation drilling is planned this financial year, depending on drill rig availability.

• Top of bedrock elevations were relatively consistent and ranged from elevation 3,800 to 3,780 feet at the Murphy Road Bridge (sloping down toward the east) and ranged from elevation 3,800 to 3,790 feet at the 3rd Street Bridge (sloping down toward the east).