Observations/Finding

On August 16th, 2023, an ASEC representative was present on-site to observe the contractor’s field activities related to the proposed Wall A. The primary objective was to visually observe the work in progress, verifying alignment with the Project Plans, Specifications, Codes and Standards, and Material Submittals.

DCP Test Data:

DCP tests were conducted at three distinct locations along the proposed Wall A alignment. These tests were performed in accordance with the data sheet provided and the reference drawing titled “WALL LOCATION PLAN VIEW” on Sheet 3.0. Before the tests, around 1.5 feet of surficial soils were excavated from the existing grade.

• DCP 1: Positioned at the center of the wall alignment, DCP penetration met refusal at a depth of 4 feet below the existing grade.
• DCP 2: Located at the southwest section of the wall alignment, DCP penetration met refusal at a depth of 4 feet below the existing grade.
• DCP 3: Positioned at the center of the wall alignment but offset from DCP 1, DCP penetration met refusal at a depth of 3 feet below the existing grade.

Subsurface Conditions:

The excavation process for the proposed shallow footings revealed loose, wet, red tan micaceous silty fine sands. The DCP measurements suggest that the density and consistency of the subsurface soils are satisfactory to support the planned retaining wall, as detailed in the reference drawing on Sheet RW-4.0.

Site Activities:

• The grading contractor was observed placing sewage pipe for lots numbered #33-37. The depth of the excavations was approximately 4 feet below the existing grade. Notably, no groundwater was detected in the utility trenches.
• The excavation process for Wall A footings was in progress. The contractor indicated that the footings would be excavated the subsequent day.

Recommendations:

The subsurface conditions appear to be conducive for the construction of retaining Wall A footings.  If the excavations become excessively wet or freeze before the concrete is placed, it’s recommended to contact ASEC for a reevaluation of the site conditions. For any further queries or clarifications, please do not hesitate to get in touch directly.