The removal of approximately 4,000 cubic yards of arsenic-contaminated ash from various sites on the island has been completed, Cabinet Minister Arden McLean said Friday.
The toxic ash, which was created by the burning of certain Hurricane Ivan debris such as pressure-treated wood, posed a long-term threat to ground water had it not been removed.
A special polyurethane-lined pit was created at the George Town Landfill to accommodate the ash, which was trucked under contract by Scott’s Heavy Equipment.
Mr. McLean said the ash removal was completed on 25 February, and that process took about a week and a half.
The public was not made aware of the transportation of the ash at the time.
‘We did not want to panic people,’ Mr. McLean said, stressing, however, that the transportation process was done properly and in a safe manner.
In the end, Scott’s Equipment was the only company that tendered a bid for the contract to truck the hazardous material, Mr. McLean said.
Stanley Scott, of Scott’s Equipment, said all the necessary precautions were taken to ensure the safety of his staff and the public.
Any of his staff that was near the toxic ash wore face masks, he said.
To ensure the public was not at risk, the ash was wetted first. After loading into trucks, the ash was covered with a layer of sand, wetted again, and then covered with a tarp, Mr. Scott said.
In addition, foam was used to seal the trucks to ensure none leaked out.
Then the trucks were cleaned before they left the landfill.
‘The trucks were washed out after each load at the landfill, with a power washer,’ Mr. Scott said.
Altogether, some eight to 10 trucks were used in the operation by Scott’s Equipment.
Mr. McLean reported there had been some concern raised by at least one individual that the trucks carrying ash were not covered properly, but he said that was not the case.
‘There were a number of trucks coming from the area that were carrying different materials,’ he said.
Although there was an estimated 4,000 cubic yards of toxic ash, Mr. Scott said he trucked just more than 5,000 cubic yards of material to the landfill pit.
Mr. McLean said that at some sites where the ash was stored, the loaders dug deeper into the ground to make sure they got all of the arsenic.
Over time and with repeated rainfalls, arsenic-tainted ash can leach into the ground and eventually in to ground water. The Frank Sound ash-storage site was located close to a main underground fresh water lens.
Water Resources Engineer Hendrik van Genderen of Water Authority said tests will be conducted on the various sites where the toxic ash was stored to detect levels of arsenic in the soil and groundwater.
‘We have quite a lot of work cut out for ourselves,’ he said. ‘Hopefully we can start [the testing] in March, and if there’s any carryover, complete it April.’
Mr. van Genderen said test samples had to be sent off island for analysis.
The toxic ash at the landfill is in the process of being covered with a layer of fine crusher-run aggregate, about eight to 12 inches in depth, Mr. McLean said.
Once that task is completed, a representative from the liner’s manufacturer will come to Cayman to oversee the pit’s covering with a sheet of polyurethane.
‘That will happen within the next two weeks,’ Mr. McLean said.
Finally, the pit will then be covered with more aggregate.
Once completed, Mr. McLean said the pit will safely hold the toxic ash for ‘200 years or so’.