Israeli scientists question need to clean up contaminated river
Environmental protection ministry plan calls for dredging sledge pools along several kilometers of the Kishon river contaminated by run-off from nearby oil refineries, chemical plants and factories.
The initial tenders for a massive cleanup of the Kishon River are due to go out in a few weeks' time, but many scientists close to the NIS 200-million-plus project question its ecological justification.
The plan, which was presented by the Environmental Protection Ministry and received cabinet approval in July, calls for diverting the course of a 500-meter stretch of the river and dredging sledge pools along several kilometers of the waterway, contaminated with heavy metals and petroleum by-products from the runoff of nearby oil refineries, chemical plants and other factories.
The contaminated sludge would be dumped in the 500-meter section of dry riverbed, where it will be treated biologically, primarily to eliminate petroleum residues. The project aims to improve the Kishon's drainage as well as to restore the river's health.
Much of the cost is to be picked up by the companies that polluted the Kishon, with Oil Refineries putting in NIS 90 million and Haifa Chemicals contributing NIS 28 million. .
The Environmental Protection Ministry says the dredging operation is vital to raising the Kishon's water quality to acceptable levels. But a number of scientists say there is no justification for this part of the project.
"According to our knowledge, the riverbed is not contaminated to the point of justifying the treatment planned by the Environmental Protection Ministry," the Volcani Center's Pinchas Fine said. Fine, together with his Volcani Center colleague Prof. Uri Mingelgrin, former chief scientist in the Environmental Protection Ministry, study sediments that were dredged from the Kishon in the past, to improve drainage, and deposited in treatment pools. Fine and Mingelgrin note that the riverbed was very polluted then, but they believe the situation is different now.
"It has been argued that the sludge piles could emit toxic gases from the breakdown of petroleum compounds, and that for that reason they must be treated, but we believe the probability of that happening is low," Fine said. "It didn't happen in the past with the pools to which much more highly contaminated sediments were moved."
Fine and Mingelgrin also say that the plan to line the bottom of the newly dry riverbed section with plastic before dumping the sludge could keep the liquid in the sludge from draining, and create conditions for pollutant emissions.
"We might be wrong in our assessments in regard to certain aspects of the project," Mingelgrin said, "but to test it you'd have to conduct a sludge-treatment trial and hold more thorough discussions with experts."
In response, the ministry said Fine and Mingelgrin were not experts in the issues of the Kishon riverbed and did not have all the information. "They asked to be involved in the project, but their research method is unsuitable to the treatment the riverbed needs," the ministry said. The statement dismissed Fine and Mingelgrin's claims, and noted that environmental impact and feasibility studies, as well as consultations with experts, led the ministry to conclude that the project did not pose a risk to public health.
"We do not have a personal interest in this, but we would be happy to have our knowledge exploited," Fine and Mingelgrin said in response. "Our goal is to improve the decision-making process and to save taxpayers' money."