Observations/Finding

At the request of the client’s representative, AS ENGINEERING AND CONSULTING, LLC (ASEC) representative, Amin Azimi visited the job site to observe he contractor’s work activities from a quality standpoint to verify compliance with project drawings/specifications, applicable codes, and materials submittals and conducted QC testing per the project drawings and specifications.  The following observations were made on site this shift:

Upon arrival to phase 7, Kelly Construction was on site with a 329 excavator, 336 excavator and Ham H12I ride on vibratory smooth drum compactor.

Starting at A1, 7 pieces of 30-inch reinforced concrete pipe (RCP) were placed on this day with approximately 18 inches of 89 stone. M10 sand was used for backfilling.  A discussion was held with the foreman from Kelly Construction on lift sizes recommending 6 inches for the trench packer and 12 inches for the full-sized compactor. The storm drain trench was not ready for compaction testing on this day.

A proof roll was performed at approximately 11:30 AM with a loaded (with 89 stone) tandem dump truck with the presence of QC, QA, ATLNext. Lane 4 and lane 3 exhibited pumping (with the exception of the west side at approximately easterly 13841.71 and beyond which could not be checked due to equipment in the way). The entire lanes 2 and 1 also exhibited severe pumping. The south 50 feet of lanes 5,6,7, and 8 were checked and also were found to be unacceptable due to pumping. All parties that observed the proof-roll QA, QC, and ATLNext agreed the entire area was unacceptable and required full remediation due to high in-situ moisture contents (possibly caused by a clogged under drain). Using a 3/8-inch probe rod it was observed that penetration of 4 to 12 inches occurred in some areas.

A discussion was held with CW Matthews who stated that the owners did not have the budget for remediation of the entire area. The owners requested further investigation with another proof-roll later in the afternoon with additional personnel including CW Matthews, the owners, Michael-baker engineer, ATLNext, QA, QC (approximately 15 people). A loaded (with M10 sand) tandem dump truck was used. QA/ATLNext managers requested that probe rods not be allowed to be used by the QA. Then a request was made initially by ATLNext to scarify and aerate some areas to lower the moisture content. Then discussions were held by several groups, and this was rescinded. A decision was made by ATLNext,  QA(including Nova and 2Mnext), Kelly Construction, and CW Matthews to re-compact the majority of the area and only complete remediation on areas approximately 22 feet x 130 feet x 6 inches and 121 feet x 27 feet x 6 inches (this was not completed while on site). CW Matthews and ATLNext discussed using P-209 in these areas (a possible RFI was going to be filed). This is not the standard for remediation according to C7.2.2 which calls for low slump in this situation. Excavation has started, but remediation was not completed by 9 pm (end of shift).

Excavation/placement storm drain pipe

storm drain

excavation

proof roll