On March 28th-29th, TIS mobilized to Cahokia, IL to clean a fuel storage tank for a major pipeline company. The 33-foot gasoline storage tank featured a steel internal floating roof (IFR), with CBI-designed legs.
After the internal floating roof legs were set in high position by TIS, the tank was diesel-flushed twice and emptied by the client. It was then isolated to prepare for cleaning. TIS accessed the tank dike and set up tank-entry equipment.
A vacuum truck was used to remove the remaining liquid through the tank’s water draw. Once the tank was completely emptied and isolated from outside piping, the entry manways were removed. Workers used self-contained breathing apparatuses (SCBA’s) to prevent respiratory exposure to vapors during this process. The tank was then ventilated with an air venturi horn and brought below 10% Lower Explosive Limit (LEL) to facilitate entry by workers.
Two-man teams entered the tank to remove sludge, build three crib towers for roof support, clean the tank interior and necessary piping, and install four scissor jacks for IFR anti-rotation support. Once the tank was cleaned, photo-documentation was taken and the tank was gas-checked for any hazardous vapors. TIS then loaded equipment and demobilized from the site April 4th-5th.