Most forecourt retailers would think twice about ignoring a faulty pump or wetstock controls, and underground tank and pipework systems – while they might be out of sight – require the same attention to detail because neglected tanks and pipes could lead to costly clean-up bills.
Raymond King, managing director of King Tanktechnic, says: “Forecourt retailers are responsible for ensuring that steps are taken to protect the public and environment from any spillage or incident on their site. This can include matters of safety such as stopping use of mobile phones, smoking and any other protective measures that ensure total control of the infrastructure.
“The hidden items such as tanks and pipework require the same TLC given to shiny pumps and posh forecourt facilities,” he adds. “Tank owners are still required to undertake a risk assessment of tankage and pipework and decide on a maintenance regime including tank and line testing, and removal of contaminants such as water and sludges.”
Retailers must undertake a written risk assessment and keep it available at all times. It must be reviewed after any changes to the site or equipment. “It must be reviewed at ‘reasonable intervals’ and written records kept,” says King. “What is a reasonable interval is a matter for discussion with, or advice from, the site retailer’s petroleum officer.”
It is important for retailers to clean and inspect tanks to assess any tank corrosion patterns on both double-skin and single-skin tanks. “This should be undertaken using contractors who can prove that they have the required trained and certified personnel,” says King. “The equipment used in this operation must also be certified for use in hazardous areas and be able to contain any petroleum sludges and washings for disposal.”
The cost of leaking tanks is unlimited – it could cost you your business and reputation. But tank replacement is costly and disruptive, so lining offers retailers an alternative. In most cases, a tank can be relined without major civil works and the site can therefore remain operational.
Paul Brettell, linings manager at Graphite UK, says: “Tank lining is a cost effective way for a site operator to give his tanks environmental protection with minimum site disruption. Retailers should look at tank lining as a proactive and cost effective step to protect themselves and their site from the costs and possible site closure linked to environmental contamination and remediation. Taking this approach would demonstrate a positive attitude towards site safety to the regulatory authorities.”
Remediation of tanks by lining must be undertaken if the corrosion reaches 40% of the shell wall thickness – that is 6mm tank wall with a 2.4mm deep corrosion. “Perforated tanks will result in the Environmental Agency taking legal action and a fine can be in excess of £20,000,” warns Raymond King at King Tanktechnic. “Remediation costs run into hundreds of thousands of pounds so it is a false economy to delay tankage infrastructure upgrades. Why pay the Environment Agency a big fine when it can be invested on your facility to increase the value of the site? Pollution issues always decrease the value of any site.
“Tank lining upgrades the tanks to given longevity of use – 25 years in most cases,” adds King. “It completely stops any further internal corrosion and protects your investment. It is a fallacy to believe tanks all corrode and perforate from outside to inside. Our experience – some 12 years lining and cleaning tanks – indicates 90% of all perforated tanks leak from the inside of the tank to the outside.”
There are a number of companies that line tanks in the forecourt environment but Graphite’s patented lining system, for example, enables an operator to initially install a three-layer system and upgrade to a five-layer system with continual real-time interstitial monitoring at a later date. The tank lining process includes degassing, cleaning and shot blasting, followed by multi layers of lining.
Graphite’s Paul Brettell says: “In our experience, while some tanks have been very badly perforated, Graphite has been able to repair and reline all tanks that we have been commissioned to work on.”
According to Nigel Plumb, director of tank cleaning company David Plumb & Co, oil companies and forecourt owners are wasting millions of pounds a year by disposing of perfectly serviceable fuel storage tanks instead of cleaning them when they have a sludge problem.
“This is done for the best of reasons – safety – but over the years we have proved time after time that tank cleaning can be done in perfect safety as well as cost effectively,” says Plumb. “The problem is that the only real way to clean a fuel storage tank is for a person to go inside and physically clean it.
“As even empty tanks contain an explosive mixture of fuel vapour and air, many companies have adopted a policy, where they have a sludge problem, of solid filling their tanks, removing them, expensively disposing of them and replacing them with new ones. In our view this is like changing the car because the ashtray is full.”
The technique David Plumb & Co uses starts with filling the tank with inert foam to drive out all the residual fuel vapour. Once this foam dissipates it leaves behind an easily removable residue. The inspection hatch is then removed and an operative, wearing full respiratory protection and personal protection equipment, goes into the tank to clean it manually. “The whole procedure, which can cost as little as £1,000, can be carried out overnight if necessary, thus causing minimum disruption,” says Plumb.
In some cases, water can be used instead of foam. When pumped out, the resulting oil-water mix is put through a separator, which cleans up the water to the point where it can be returned to the water cycle, with just the dregs needing disposal – therefore making considerable savings on disposal costs.
The system can also be used to cut out the separating baffle plates in dual compartment tanks. “These were commonly installed in low capacity sites in previous years, when most garages sold two-star, three-star and five-star as well as four-star petrol,” says Plumb. “Now that larger tanks are required, these old duel compartment tanks can be made into a single unit and re-used.”
All underground pipework must be manufactured from a non-corroding plastic material and be sufficiently flexible to allow for ground movement to occur without placing stress on joints or end connections, according to pipework expert PetroTechnik, which supplies Universal Petro Pipe (UPP) and the FuelBank bunded fuel storage system which provides a total self-contained unit comprising end cabinet, pump, management system, valve and gauges.
“Thankfully today’s environmental legislation is tougher than ever, and UPP’s commitment to 100% safe and efficient fuel delivery means that sometimes even UPP Extra single wall pipe is not enough,” says a spokesperson for PetroTechnik. “The UPP secondary contained pipework system has been designed to comply with regulatory bodies throughout the world for use in high-risk environmentally-sensitive situations.”
The system features a 40mm co-axial sleeve which is co-extruded over the 32mm UPP Extra primary pipe leaving an interstitial space between the tank and the pipe termination, allowing for leak detection connections to be made if required.
“The semi-flexible UPP Extra and secondary containment pipe systems are both superior alternatives to copper and iron supply and return lines in fuel oil applications,” says the spokesperson. “One continuous length of semi-flexible UPP pipe can be used from storage tank to an above ground, or building termination, and even with joints the electrofusion welding principle behind the UPP system means that once welded the pipe-run is one homogeneous structure with no possibilities for leakage.
“Manufactured from high-density polyethylene, the UPP system is extremely tough, corrosion resistant, and, once installed, should need no further maintenance.” UPP is equally suited for suction or pressure pump systems and comes in a range of sizes and combinations. There are now more than 15,000 installations of the UPP piping system in 118 countries.
PetroTechnik also supplies the PetroFast complete forecourt system, and supermarket chain Morrisons has recently chosen the modular filling station package for its site in Keighley, West Yorkshire. According to PetroTechnik, PetroFast makes it possible to transform a bare site into a filling station in just three days. The underground tanks, UPP pipework and canopy are all factory assembled for rapid on-site installation.
A spokesperson for the company says: “With PetroFast customers can specify the level of pre-build. You can choose from just the basic tank and mounted canopy support to a full pressure-tested underground system with canopy in place. The modular nature of the system makes it suitable for any size of site, whether it is new-build or refurbishment.”
For Morrisons, two 81,800-litre tanks were manufactured complete with canopy supports, man-way chambers and base frames. “Once the excavation had taken place, PetroFast was off-loaded and lifted into place within minutes,” says the spokesperson. “The concrete pouring was complete in less than two hours and the backfilling started immediately after that.”
Operating in an increasingly environmentally conscious society, it has never been more important to give tank and pipework installations the attention they require.