{"id":176761,"date":"2017-04-28T14:33:05","date_gmt":"2017-04-28T09:03:05","guid":{"rendered":"https:\/\/www.colombotelegraph.com\/?p=176761"},"modified":"2017-05-03T03:05:26","modified_gmt":"2017-05-02T21:35:26","slug":"toxic-dust","status":"publish","type":"post","link":"https:\/\/www.colombotelegraph.com\/index.php\/toxic-dust\/","title":{"rendered":"Toxic Dust"},"content":{"rendered":"

By Ranil Senanayake<\/a> \u2013<\/strong><\/span><\/p>\n

\"\"<\/a>

Dr Ranil Senanayake<\/p><\/div>\n

Watching the black oily sand that is being pumped from the ocean bottom off Kerewalapitiya, is watching yet another tragedy unfolding due to the low level of sensitivity to environmental factors by those who prepared the SEIA. Perhaps they were too young to remember the Tsunami. The sludge that came up with the wave of the Tsunami prompted the following observation published in the press<\/span> <\/b>in 26\/1\/2005<\/span><\/p>\n

\u201c The tsunami also produced many nasty surprises, such as the\u00a0<\/span>Return of our garbage over the last couple of centuries. Witnesses and\u00a0<\/span>survivors spoke of a \u2018stinking black oily mud\u2019 that accompanied the\u00a0<\/span>wave in many areas. The substance covered floors and tiles of houses\u00a0<\/span>after the event. There have been numerous reports of people getting\u00a0<\/span>sick from exposure to it via the flood or from just stepping in puddles\u00a0<\/span>of sludge.\u00a0<\/span>Sri Lanka is an island with a narrow but fairly flat offshore shelf\u00a0<\/span>that extends to the continental shelf. All the garbage, pollutants,\u00a0<\/span>toxins and topsoil that was dumped into the ocean combine with\u00a0<\/span>ship-based oil and organic pollutants to form lenses of toxic sludge\u00a0<\/span>on the flatter plains beyond the reefs. The force of wave creation, as\u00a0the oncoming tsunami entered shallower waters, lifted this deposit\u00a0<\/span>into the oncoming wave.<\/span><\/p>\n

The load of toxic sludge is now deposited on our shoreline mixed\u00a0<\/span>with the debris of the aftermath. Toxic marine sludge from other sites\u00a0<\/span>have been found to contain PCB\u2019S, TBT\u2019s, dioxins, heavy metals and\u00a0<\/span>chlorinated hydrocarbons \u2013 all chemicals that can damage human\u00a0<\/span>health and lead to cancers and other longer-term health effects. It is\u00a0<\/span>important that we do not dispose this debris back into the ocean nor\u00a0<\/span>put it in areas of human habitation.\u201d<\/span><\/p>\n

The colour of the sediment that is being dumped in front of Colombo is disturbing.\u00a0 <\/span>It is reminiscent of the toxic sludge disturbed and brought ashore by the Tsunami. The dredging of the bottom is being done directly in the settling zone of all the pollutants discharged by the city and the river.\u00a0 <\/span>The tragedy is that the SEIA recognizes this fact\u00a0<\/span><\/p>\n

\u201cRecorded maximum concentration is 4mg\/l at the dredging site which is far below the recorded maximum ambient TSS levels during flood event of Kelani River. Therefore, increase in suspended sediment level during dredging operations is negligible and therefore no significant impact occurs during dredging operations. The proposed sand dredging area, experiences high turbidity conditions due to the discharges from Kelani River and hence the existing organisms have higher tolerance level to high turbidity levels.\u201d (Chapter 7 pg. 1. SEIA) <\/span><\/p>\n

By this statement it is obvious that the dredging is going on in the zone where the outflow from the city and the river settle. The SEIA lulls us into a state of false security when it states that it is not a dynamic zone, But, if this is not a dynamic zone where materials move all the time, there will be\u00a0 <\/span>much accumulation of sediment. It is amazing that they did not consider the materials they would be dredging up with the sand.<\/span><\/p>\n

Perhaps they should have considered the studies done on the coastal zones of\u00a0 <\/span>other places. The US Geological Survey report<\/a> is an example:\u00a0<\/span><\/p>\n

They point out that this zone \u201cis impacted by many activities, such as fishing, recreation, housing, sewage and waste disposal, shipping, and preservation. In many cases, especially adjacent to major metropolitan and agricultural areas, the sediments are polluted and the ecosystem has suffered detrimental effects.\u201d <\/span><\/p>\n

In summary, the geochemical studies in a variety of coastal environments show that:<\/span><\/p>\n