An underground storage tank inspection is often recommended when considering its removal. Will the structure near the tank be affected? What are the risks? What are the approximate costs? Penn Valley Engineering is available to perform an inspection of the structural significance a tank removal’s impact might cause.
This narrative covers an underground storage tank inspection that Penn Valley Engineering performed at a commercial property in Philadelphia, PA 19114. The building’s owner was considering having the underground storage tank (UST) removed. Because the structure is adjacent to other business properties, the removal of the tank could impact others. Markedly an inspection was necessary.
Locating an Underground Storage Tank for Inspection
In this case, the business owner provided design plans from the building’s original construction. Additionally, the owner had the UST located by a company specializing in locating underground tanks before our inspection. This is valuable information for any business or homeowner to have prior to an inspection.
The UST was located in the front exterior of the business. A loading dock was located on the side, near the UST. The original plans detailed a concrete footing supporting the building’s exterior walls. The tank was less than 5 feet from the front wall. It was determined the depth was just over 8 feet below grade. The tank measured approximately 5’ 6” in diameter and 14’ in length.
Risks of Removing an Underground Storage Tank
Based on the conditions at this location, removing the UST would undermine the adjacent foundation of the front wall of the building. If no action is taken before the tank’s removal, it is impossible to know the resulting consequences fully. However, it is far too large of a risk to take without taking the necessary precautions.
If the UST is removed, the adjacent foundation needs to be secured. PVE recommended installing appropriately designed helical piles along the foundation of the front wall. Our structural engineer also recommended installing appropriately designed temporary shoring and bracing during the UST removal.
Cost of Removing an Underground Storage Tank
Costs for removing an underground storage tank vary greatly. Each location and situation demands specific plans and protections to be put into place. In this particular location, the approximate construction costs for the helical pile installation and temporary shoring and bracing were provided to the business owner. The engineering and repair plan (blueprint) fees for the repairs would be an additional expense and would be provided by Penn Valley Engineering. The building’s owner would also need to budget for cosmetic repair and/or restoration that would be needed for the parking and loading dock area for his business.
Option for Tank Removal
The company that located the UST noted that it can remain in place should removal prove burdensome. The tank could be cleaned out and filled with appropriate material. Applicable codes and procedures for UST environmental remediation from an appropriate professional must be consulted. PVE does not specialize in this area but can recommend other professionals.
If filling in the UST instead of having it removed, access to complete the appropriate remediation can be made at the top of the UST. Excavation in this area must be kept to a minimum to avoid disturbance of the soils supporting the adjacent foundation. The contractor must use an associated plan set to complete any excavation. Much care would need to be taken when gaining access to fill in the UST.
Other Considerations for Removal and Inspecting an Underground Storage Tank
Overall, an underground storage tank inspection can present many challenges and difficulties in having it removed. Furthermore, retrofit construction requires all corrective efforts to be properly designed and detailed with construction document blueprints. In some cases, it is even required that all work be monitored and supervised by a professional engineer licensed by the State of Pennsylvania.
In conclusion, if you are considering removing a UST, reach out to us. All work will need to be completed by an experienced and knowledgeable State Licensed contractor, with all necessary permits, approvals, and inspections. We can assist you through the process. If you are located within our service areas contact the PVE office nearest you. We look forward to meeting you!
- (856) 872-3537 SOUTH JERSEY
- (215) 821-7686 PHILADELPHIA
- (321) 394-8026 CENTRAL FLORIDA
“PVE was very professional and a pleasure to work with. They provided guidance, expert insight and remediation for me.”
– C Yayac, reviewing structural engineering in Island Heights, NJ 08732