Oneline successfully won the tender for a tank cleaning project at Weymouth Sewage Treatment Works.
All work to be undertaken was underground, and with a tank size of approx. 60m x 25m x 9m deep, the method of work, safety plan and equipment all had to be carefully thought through.
Once the client had emptied the tank to a depth of 400 – 500mm, the task was to remove sludge and rag that had built up over a number of years. Oneline used one of their recycling units and their deep suction tanker to suck out liquid and rag/grit. Once they had separated out the rag, the liquid was decanted back into the works, and the rag/grit was transported to Avonmouth STW for recycling.
To complete the project efficiently and on time, Oneline had 6-8 people on site working in shifts of approximately one hour in the tank.
Oneline used specialist equipment such as two Davit lifting devices, extra gas monitors, extra escape kits and additional air movers.
Because Oneline were successful with the outcome of the works, we will be invited to tender for the works to clean out the next SBR tank requiring attention.