Observations/Finding

On October 9, 2023, Vidal Dias from ASEC visited the Kimball Bridge Road project site to perform geotechnical observations. The surficial layer in the planned dam area primarily consisted of wet alluvium. An over-excavation depth of approximately 3 feet was performed to prepare the subgrade. The exposed base of the subgrade was observed to be a composite of tan-gray-red silty medium to coarse sands, which also included rock fragments and a minor fraction of clay.

The area was probed using a 3/8″ diameter probe rod, which revealed a maximum penetration depth of 2 inches. This suggests the presence of a relatively dense subsurface layer. Following these observations, a bridge lift was constructed using red, slightly micaceous sandy clays. The material was subsequently compacted using a sheeps-foot roller.

For any further inquiries or clarification related to this report, please contact ASEC.