Observations/Finding

Observations/Finding

As requested, the site was visited by our AS Engineering and Consulting (ASEC) representative for the purpose of providing quality control inspection and testing services.  Visual observation techniques were employed to verify compliance with project drawing/specifications, applicable codes, and materials submittals. The following observations were observed on site this day.

Construction Activities Monitoring Report

On the mentioned date, the AS Engineering and Consulting LLC engineering representative was on site to observe the construction activities in progress at the project site. The work took place from 10:00 AM until 17:00 PM and included the following activities:

• Embankment work in Lots #7–9.

• Drilling of holes between Manhole 9 and 9A was performed.

• Excavation and placement of sewer pipe and manholes with backfilling of the sewer line from 2A to 3A.

1. Embankment Work
Embankment activities were ongoing in Lots #7, 8, and 9 with the depths 7, 11, and 13 feet respectively, below finished grade. Rock sizes encountered varied, with some boulders exceeding 2 feet in diameter. Our ASEC representative recommended breaking down the oversized boulders into smaller diameters as per project specifications. It was further advised to thoroughly mix these crushed, smaller boulders with fine-grained material – with an even mixture of the two – and compact each lift using a Caterpillar 815K roller.  The boulder fill should not be placed within 4-feet of the bottom of the footings.

Due to the onset of rain, the embankment contractor only worked until 13:00 only.

2. Drilling between Manhole 9 to 9A and lot#23
The drilling crew of advance explosive company worked between manhole 9 to 9A and Lot #23, drilling holes spaced approximately 7 ft x 7 ft apart at a bit diameter 3.5inch, continuing until 05:00 pm. The drilled holes were randomly checked for depth which was drilled as per the log sheet recorded by the drill operator. The drilling results were as follows.

• Drill #1: 51 holes, depth of 15 ft, rock encountered at 2–8 ft   between Manhole 9-9A.

• Drill #2: 57 holes, depth of 15 ft, rock encountered at 6–8 ft between Manhole 9-9A.

• Drill #3: 98 holes, depth of 11 ft, rock encountered at 0-6 ft at Lot #23.

3. Excavation, Placement of sewer pipes and manhole, and backfilling of the sewer line from 2A to 3A

On the mentioned date, excavation, placement of sewer pipes and manholes, and backfilling of the sewer line from 2A to 3A were in progress. The contractor placed 8-foot-long concrete sewer pipe sections with a 2-foot inner diameter, which were placed by the assigned crew. A plug check was conducted to verify the moisture contents of the backfill material placed over the sewer pipes, and the results were within the acceptable optimum moisture content range for achieving compaction. It was advised that backfill layers should not exceed 8 inches in loose lift thickness. The backfill material was checked using a probe rod for a stability check. Additional compaction was recommended by the ASEC engineering technician to the crew. During the observation, the backfill on both sides of the sewer pipes and manholes was found to be significantly soft and loose; therefore, further compaction was recommended.

4. Equipment in Operation
The following machinery was used for the day’s activities:

a. Embankment crew equipment

• 1 Dozer

• 1 Roller, Caterpillar 815K

• 2 Trucks

• 2 Excavators

b. Drilling crew equipment

• 3 Drill machines

c. Sewer line  crew equipment

• 1 Excavator
• 1 big roller
• 1 small remote-control roller
• 1 jumping jack compactor
• 1 Loader with fork

The work progressed smoothly, and all activities were completed without major issues.

We appreciate the opportunity to be of service to you on this project. If you have any questions regarding this report, please feel free to contact us. We will be more than happy to discuss it with you.

Rock fill Embankment work in progress

Rock fill Embankment work in progress

Rock fill Embankment work in progress

Rock fill Embankment work in progress

Mass rock drilling in progress

Mass rock drilling in progress

Mass rock drilling in progress

Mass rock drilling in progress

Sewer line back filling in progress

Sewer line back filling in progress

Sewer line back filling in progress

Sewer line back filling in progress

Sewer line back filling in progress

Sewer line back filling in progress

Sewer line back filling in progress