Observations/Finding

Purpose of Visit:
At the request of Tyler Baker with Toll Brothers, ASEC representative Ram Mogulla visited the site to provide quality control oversight. Visual inspections were conducted to verify compliance with project drawings, specifications, applicable codes, and material submittals. The following observations were made on site.

Site Observations:

1. Repair Process of Retaining Wall 2A Foundation:
   • Observed at the northeastern section of the site.
2. Cause of Wall Failure:
   • The exact reason for the wall failure has not been determined by ASEC.
   • Based on discussions with Chris Settles of Grounded Engineering Services, the failure was attributed to the clogging of the 30-inch storm drain installed below Wall 2A, which created hydrostatic pressure behind the wall. The obstruction was cleared before demolition.
3. Subsurface Bearing Capacity:
   • The bearing capacity of the subsurface soils where the leveling pad was installed was not assessed, as the repair did not involve replacing the entire height of the wall.
4. Demolition and Preparatory Work:
   • By the time ASEC arrived, demolition was completed. Attached photographs show the demolition and preparatory work for the repair.
5. Repair Process Observation:
   • Over the next two days, ASEC observed the repair and installation process, including quality control testing by an engineering technician from Grounded Engineering Services.
   • Testing results and wall certificates will be provided by Grounded Engineering Services.
6. Compliance with Design Drawings:
   • Observed the installation of geosynthetic reinforcement, drainage aggregate, and the compaction testing of the structural fill, as required by the design drawings prepared by Grounded Engineering Services dated October 5th, 2021.
   • The repair appeared to be performed in accordance with these design drawings.

Conclusions and Recommendations:

The repair work for Retaining Wall 2A appears to have been conducted in accordance with the specified design drawings and standards. For any further questions or detailed discussions regarding our observations or conclusions, please feel free to contact us. We are available to provide additional services or input as necessary to ensure the successful completion of this project.

Attachments:

• Photographs of the demolition and preparatory work for the repair.

Removal of Geosynthetic reinforcement

drainage aggregate

Installation of Geosynthetic reinforcement

drainage aggregate

Geosynthetic reinforcement

Compaction Efforts