Observations/Finding

Our ASEC representative was on-site as requested by the client and/or contractor to observe the installation of a geosynthetic drainage system (referred to as a ‘burrito’) designed to facilitate water drainage and stabilize the wetland area.

Site Conditions and Work Observed:

• Project dimensions: The specified excavation spanned 100 feet in length and 20 feet in width, to a depth of 4 feet.
• Subgrade evaluation: Probing techniques identified subgrade materials as red, gray silty fine to medium sands interspersed with rock fragments and clay strata.
• Geotextile installation: A layer of Terratex N04 non-woven geotextile was positioned over the probed subgrade.
• Aggregate placement: #57 stone was laid to a uniform depth of 3 feet over the geotextile layer.
• French drain installation: Concurrent with the stone placement, a French drain system was integrated within the aggregate layer to enhance subsurface water drainage.
• Geotextile encapsulation: The aggregate and embedded French drain were then covered with a second Terratex N04 Nonwoven geotextile layer, make sure the two layers were overlapped.
• Initial backfill: Following the geotextile encapsulation, a 3-foot bridge lift of tan, red-gray silty medium to coarse soils with rocks and boulders was placed. The included rocks and boulders ranged in size from 8 inches to 20 inches.
• Upper layers backfill: Over the boulder fill, 6-inch lifts of Red to Brown Micaceous Sandy CLAY were compacted.

AS Engineering and Consulting, LLC. Appreciates the opportunity to be of service to you on this project. If you have any questions regarding this letter, please contact us.