The detectable hydrogen sulfide levels were over 100 ppm prior to the introduction of the chemicals and were reduced to non-detectable levels upon completion. The project was performed on the exterior of the vessel by introducing the selected chemicals through a proprietary nozzle and pumping system designed to insure the bottoms agitation. Nozzles were then installed on the external floating roof and through the tank side manways, therefore no manhours were required inside the vessel.

The recovered oil was then processed to the plant coker unit, and the wastewater from the cleaning process was approved for disposal on-site at the wastewater treatment plant. The tank was approved by maintenance staff for a change of service.