By P.K.Balachandran/Daily Express
Colombo, April 20: A scientific study of garbage disposal in Colombo done by EML Consultants Pivate Ltd.,for the Central Environment Authority (CEA) had concluded that sanitary land filling would be the only practical way of disposing Municipal Solid Waste (MSW) in Colombo, the Ministry’s former Secretary, Gotabaya Rajapaksa, said here on Thursday.
Speaking to Daily Express, Rajapaksa said that the final report released by the Ministry of Urban Development in August 2015, had recommended that sanitary land filling should take place at Aruwakkalu in Puttalam district, 170 km from Colombo.
The garbage, collected and stored at Meetotamulla in the outskirts of Colombo, should be transported to Aruwakkalu by rail on a daily basis. Taking it by road was ruled out. At Aruwakkalu it was to be dumped in a disused limestone mine which was attached to the Holcim cement factory. The disused mine has a capacity of 4,700,000m3.
The Aruwakkalu project was to be implemented in two phases. Phase I was to be implemented over 17 hectares for five years. Phase II, over 13 ha, was to cover the next five years. The final height of the landfill was to be 40 m from the ground level.
The bottom of the landfill would be formed by laying down gravel or crushed stone for 30 cm and a 1,000 g/㎡non-woven fabric. Further, a Bentonite mixture of 30 cm and 1.5 mm and an HDPE sheet would cover the top of the non-woven fabric. The top of the HDPE sheet would be covered with 1,500 g/㎡ of non-woven fabric. Leachate collection and treatment systems were incorporated in the design.
The Aruwukkalu site was found to be geologically safe as it was already a mine. Hydrological date showed that there was no danger of ground water pollution. Dirty water could be recycled and diverted to the fields around to support wild life.
Environmentalists who examined the Aruwakkalu site found that there was no threat to the flora and fauna in the adjacent Wilpattu Wildlife Sanctuary, except one species of flora “dendrophtho ligulata”. It is in the Red List of threatened flora, but adequate measures can be taken to conserve it.
Compost produced at the Aruwakkalu dumping site could be sent to the vegetable growers in Kalpitya and also nearby Mahaweli areas, the report said.
The Meetotamulla dumping site was to remain but only as a collection and transit station for the garbage en route to the Aruwakkalu land fill.
The consultants suggested that the Meetotamulla site be sanitized so that the garbage put there temporarily did not become a health hazard and a threat to the environment. Today it is even polluting the ground water and the Kelani river.
According to the environment assessment report, the cabinet sub-committee appointed to go into the issue had accept the recommendations, and the cabinet itself had approved it. However, it is reported that the necessary clearance from the Wild Life Department could not be obtained.
Gotabaya Rajapaksa firmly ruled out the conversion of municipal solid waste into composed on a large scale as this is not practical when the daily addition to the garbage mound is of the order of 1000 mt. He also said that it would be senseless to talk of generating electricity from garbage as it would be too expensive.
“Sanitized land filling is the most practical in Sri Lanka’s case. In my travels abroad as Secretary Defense and Urban Development, I had enquired about garbage disposal methods and I was convinced that given the conditions prevailing in Sri Lanka, sanitized land filling is the best,” Rajapaksa said.
(The featured image at the top shows former Defense and Urban Development Secretary Gotabaya Rajapaksa)