Horticultural waste continued accumulating at Pembroke Dump for about five months while machinery to treat it was broken, Government staff have revealed.Government yesterday confirmed its pro-grinder, the equipment which breaks down plant waste discarded at Marsh Folly, has been out of service since November last year.Staff told The Royal Gazette this caused piles to get excessively high, leading to fears it was becoming hazardous ahead of last Thursday’s massive fire.The huge Marsh Folly blaze of 2007 was blamed on broken grinders, which meant the mound of waste grew to the height of an eight-storey building and eventually self-ignited in hot, dry weather.Shadow Public Works spokesman Mark Pettingill last night cast doubt on Government’s claims last week’s fire could have been started by a carelessly discarded cigarette.Mr Pettingill said spontaneous combustion of composting waste is a more likely cause.The Ministry of Public Works, which insists it has learned its lesson from the mistakes of five years ago, argued this time piles were kept at a manageable level less than six metres tall.A shredder remains operable, said a spokesman, and the piles have recently been turned over with an excavator which did not reveal any hot spots.But yesterday one staff member told this newspaper he had noted piles were getting big due to a broken grinder, adding: “I said it was a hazard waiting to happen.”Responding to our questions yesterday, the Works spokesman said Government owns one pro-grinder, which has been out of service since November 8 and should be available again today.“We are in the process of completing a major repair to the drive fluid coupler, we also have made a purchase of parts as recommended by the manufacturer’s engineer on his last visit to service the unit,” said the spokesman.Asked whether any equipment is dealing with the mounds, he replied: “We have a shredder that is operable.”Asked for a response to staff’s claims that the piles got too high due to one grinder being out of use, the spokesman said: “The piles have been maintained at a manageable height and size so as to minimise the risks of fires.“None of the piles exceeded six metres in height and they had been recently turned over with an excavator. This exercise did not reveal any hot spots in any of the piles.”Mr Pettingill said in a statement last night: “I’m not convinced that the fire was started by arson or by a discarded cigarette, as a Public Works official has claimed.“I think it is far more likely that it was started by the spontaneous combustion of shredded material towards the end of a long period during which there was no rain to dampen the dump down.“This is a hazard that comes with the process of composting horticultural waste. When it decomposes, heat is created which, if left undampened by rain, will eventually cause fire.“These fires are often deep-seated, well below the surface of the material. Spraying water on the top of the material has a limited effect.”Mr Pettingill said the best way to reduce the risk of fire at the dump is to increase the amount of horticultural waste burned in the incinerator.“There is no question that composted horticultural waste is needed in Bermuda, and that our waste plant material cannot all be fed through the incinerator,” he said.“But less composting waste will tend to reduce the risk of fire, and sensible management of the proportion that is left to rot down and the proportion that goes to the incinerator seems to me the way to proceed.”He also spoke on Government’s vow to stop fires at the dump once and for all.“A spokesman declined to elaborate when the press asked how this was to be achieved,” noted Mr Pettingill.“I think Government should come clean with the public on exactly what it has in mind, otherwise the public will feel its statement was just one more in a long line of unfulfilled promises which have little more purpose than to calm people’s anger over the inconvenience and the aggravation to their health.”Meanwhile the Ministry of Health issued the following water safety tips for residents concerned about the quality of their water supply:l Immediately following the fire, residents were advised to block gutters until the arrival of the next hard rain in order to lessen the impact of particles entering the tank. This time has now passed;l Residents have been advised to drink bottled water in the short term as the fine horticultural particulates, although not toxic to the water supply, may dirty the tank;l Homeowners who have not cleaned their tanks in the past six years should take the opportunity to do so now;l Homeowners whose roofs are dirty and have not been painted in the past two years should take the opportunity to do so now;l Testing results from the last major fire indicated that contaminant levels still fell within drinking water quality guidelines. However, current testing arrangements are presently underway, the results of which will be released to the public as soon as testing is completed.l In the absence of regular treatment or disinfection, residents are reminded to always boil tank water before drinking.