Case study 2
Site Visit on 12th March 2002 - to carry out 13 meter resets, 4 from tank 3 UL.
Not possible to carry out resets on pumps from tank 3 as gauge reading in excess of 240mm of water, some had been drawn up through Pump 12 into a customers car that broke down immediately.
Actions taken by the site
- All UL nozzles were put out of service straight away until they identified that tank 3 was reading such a high level of water.
- Hoses from tank 3 - isolated and arrangements made for contractor to remove water from tank.
- Off set fill opened in the tank manhole - contractor found dipstick in offset fill pipe.
- Tank dipped from this opening - no product detected in the fill pipe some left in the tank but only water detected in fill pipe.
- Water completely removed and almost immediately fluid could be seen entering the tank, the tank viewed for over an hour by which time there was 10mm of product, possibly drained out of the suction lines, and 30mm of water - bubbles and ripples could still be seen when looking down the open fill pipe.
Conclusion
- Identified that dipstick has been left in the off set fill pipe.
- During delivery these dipsticks spin, turning the stick into a drill.
- In the case of this site, 20000 litres may be dropped into one tank at a time. This can drill through the bottom of the tank as the bottom of the dipstick had developed a sharp point due to the rotational friction.