Excavation trenching

A "pipe trench" is an installation of process and utility piping on supports within a below grade, open excavated trench. Pipe trenches may provide some protection from damage due to explosion overpressures or explosion fragments or missiles. 

That which is termed Pecton, i.e., concreted and congealed Vitriol which forms in caves and grottos, and brought afterwards by a simple process into excavated trenches, assumes a concrete form. 

If a slurry wall cannot be keyed into an impervious stratum at its base, a bottom barrier may be required. Such barriers may be constructed by horizontal drilling from excavated trenches, or by directional drilling from the ground surface as shown in Figure 22.2. (Bottom barriers made with directional drilling are generally done by grouting). Both methods are costly. See References [2] and [3] for details of bottom barrier construction. 

A. High-Emphasis Hazards are targeted and include fall hazards and hazards identified from the following National Emphasis Programs (NEPs) amputations, combnstible dnst, crystalline silica, excavation/trenching, lead, and shipbreaking. See section XII. (p. 5). 

J. Excavation/trenching hazards specified below that are covered by the Special Emphasis Program— Trenching and Excavation (See CPL 02-00-069)... 

Steel sheet piles are Interlocked steel sections driven into the ground to resist side pressure on the excavation trench. 

Well point is a long thin tube which is installed vertically into the ground and through which groundwater is pumped. A well point system is a system of well points situated around the excavation area and used to pump out groundwater and reduce the flooding risk in the excavation trench. 

Excavate trench and use bentonite slurry to support excavation... 

Emergency response and planning Ergonomics Excavations/Trenches Fall protection... 

Have barricades been placed around excavation/trench 3 ft. from the edge ... 

The most common method for locating material that will provide information regarding sea-level change is the use of a vibrating sampler, provided that samples are sfightly moderately disturbed. The method of excavation trenches is also often used for smaller depths. 

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