INSPECTION & LEAK DETECTION
Founded in 1935 to blend and sell lube oil, Coast Oil Company - based in San Francisco Bay, Northern California - is today one of the largest distributors of gasoline, diesel fuel, and lubricants in the USA. To meet Regional Water Quality Control Board standards for the prevention of ground water pollution, the company recently installed new leak detection equipment at its San Jose tank farm. The particular challenge was to retro-fit an exiting facility with stare-of-art leak detection to monitor the soil below the above ground storage tanks while keeping the normal day-to-day business running smoothly. The solution chosen was Tyco Thermal Controls' TraceTek 5000 sensor cable installed in slotted PVC pipe. The sensor cable is a popular AST leak detection solution, but in the past has been installed in large facilities with widely spaced tanks where manoeuvring the construction equipment was not a serious challenge. In Coast Oil's San Jose facility, the cable was being fitted to 12 tanks that were relatively small in diameter and very tightly packed. The standard technique for installing the sensor cable is to position slotted PVC conduit beneath the tank floor plates using horizontal boring equipment. For the Coast Oil project, the limited working space proved to be a major problem. The installation contractor - CorrPro Companies Inc - used its smallest and most manoeuvrable horizontal drilling machine, operating an air-ram boring tool rather than a rotating drill bit. At the perimeter of the tanks, the horizontal conduit was fitted with a vertical riser and a small junction box.
