503 EM 385-1-1 SECTIONS 20-26

25.A.02 Excavation Testing and Documentation.

> See Table 25-1.

1. When workers will be in or around an excavation, a CP for Excavation must inspect the excavation, the adjacent areas, and protective systems daily. Inspections must also be completed: before each work shift, throughout the work shifts as dictated by the work being done; after every rainstorm; when fissures, tension cracks, sloughing, undercutting, water seepage, bulging at the bottom or similar conditions occur; when there is a change in size, location or placement of the spoil pile; where there is any indication or change in adjacent structures; and after other events that could increase hazards (e.g., snowstorm, windstorm, thaw, earthquake, etc.).

2. The CP must be able to demonstrate:
• (1) Training, experience, and knowledge of soil analysis, use of protective systems, and requirements of this Section and 29 CFR 1926 Subpart P;
• (2) Ability to detect conditions that could result in cave-ins, failures in protective systems, hazardous atmospheres, and other hazards including those associated with confined spaces; and
• (3) The authority to take prompt corrective measures to eliminate existing and predictable hazards and stop work when required.

4. Testing for soil classification must be of an approved method: pocket penetrometer, plasticity/ wet thread test or visual test and must be conducted at a minimum of once prior to the start of each work shift or, if conditions warrant, as described in Section 25.A.02.a.
5. All testing for soil classification must be determined by the CP, documented , and maintained for the life of the project (i.e., QC daily reports, excavation inspection log, etc.). > See Table 25-1.
Table 25-1 - Soil Classification

Soil Type	Criteria	Other Considerations
Stable Rock	Natural solid mineral that can be excavated with vertical sides and remain intact while exposed.
Type A	Cohesive soil with an unconfined compressive strength of 1.5 tons per square foot (tsf) (144 kPa) or greater.	Can not be Type A if soil is: 1) fissured; 2) subject to vibration from heavy traffic, pile driving, etc.; 3) previously disturbed; 4) part of sloped, layered system where layers dip into excavation on a slope of 4H:1V or greater; or 5) subject to other factors requiring it to be classified as less stable material.
Type B	Cohesive soil with an unconfined compressive strength greater than 0.5 tsf (48 kPa) but less than 1.5 tsf (144 kPa).	Type B soil can also be: 1) granular cohesionless soils such as angular gravel, silt, silt loam, sandy loam, and in some cases, silty clay loam and sandy clay loam; 2) previously disturbed soils except those which would otherwise be classed as Type C soil; 3) soil that meets the requirements of Type A, but is fissured or subject to vibration; 4) dry rock that is not stable; or 5) part of sloped, layered system where layers dip into excavation on a slope of 4H:1V , but only if the soil would otherwise be classed as Type A.
Type C	Cohesive soil with an unconfined compressive strength of 0.5 tsf (48 kPa) or less.	Type C soil can also be: 1) granular soils including gravel, sand, and loamy sand; 2) submerged soil or soil from which water is freely seeping; 3) submerged rock that is not stable; or 4) part of sloped, layered system where layers dip into excavation on a slope of 4H:1V or steeper. Can NOT be benched!

6. If evidence of a situation that could result in possible cave-ins, slides, failure of protective systems, hazardous atmospheres, or other hazardous condition is identified, exposed workers must be removed from the hazard and all work in the excavation stopped until all necessary safety precautions have been implemented.
7. In locations where oxygen deficiency or gaseous conditions are known or suspected, in excavations 4 ft (1.2 m) or greater in depth, air in the excavation must be tested prior to the start of each shift or more often if directed by the GDA. A log of all test results must be maintained at the work site. > See Sections 5 and 6.

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