Incineration is Bermuda's chosen solution for disposing of that portion of Bermuda's waste stream which is burnable but will not be recycled or composted. The incinerator, one of the most modern and tested systems developed, will shrink Bermuda's volume of burnable waste by 90 to 95 percent.

And according to the Proposed Comprehensive Waste Management Plan for Bermuda by the Ministry of Works and Engineering, the ash will be bound in concrete to virtually eliminate environmental impact.

This process for elimination has been tested abroad for almost a decade. And Dr. Robbie Smith, assistant research scientist at the Bermuda Biological Station is pioneering Bermuda's own experiments concerning the performance of ash blocks in the water.

"Ash contains some toxic material ,'' said Dr. Smith. "And our main goal is to seal the harmful substances in the concrete so they don't interact with marine life.'' When the Development Applications Board approved the incinerator, they set down conditions that the Ministry of Works and Engineering continually monitor the ash blocks in the ocean. The Ministry asked the biological station to perform the observations.

"We started testing the blocks nine months ago,'' said Dr. Smith. "And thus far, we have no results. But it's early yet. We need five to ten years to fully evaluate the ash blocks and how they function in water.'' Dr. Smith and his research team are comparing ash blocks, which are a mixture of ash and concrete, to pure concrete blocks.

"Ash is an inconsistent substance whereas concrete is very homogeneous. We must determine whether or not the ash block is strong enough to keep its form.

And we've built a set of artificial reefs by stacking blocks together in both Castle Harbour and Tyne's Bay to do so,'' said Dr. Smith.

The Government plan is to dispose of the ash in Castle Harbour. But it may one day be discarded near the incinerator. "Castle Harbour is significantly different than the North Shore so we're testing the blocks in both bodies of water now,'' said Dr. Smith.

The Biological Station is importing ash from the United States for the experiments which are being done conservatively to minimise any risks. "We mix the ash with more concrete than suggested,'' said Dr. Smith.

Experimental blocks are one foot cubes made up of about 85 percent ash. The Government has planned the manufacturing of 28 cubic metres of ash per day.

"But the estimate was made before Government established recycling in Bermuda,'' said Dr. Smith. "The figure could be much lower.'' Environmental impact on marine life is a big question. "A host of different animals will colonise the blocks and bore into the concrete. Over a long period of time, this could lead to the ultimate breakdown of the blocks,'' said Dr. Smith.

"And an abundance of these boring organisms can be found in Castle Harbour,'' he added.

"We must also determine if other species living between the artificial reefs will accumulate toxins. And we can use that information to see how much harmful material is emanating from the blocks.

"If we can't detect any over time, we'll know we've been effective in preventing any toxin loss,'' said Dr. Smith.

"But it's hard to predict what might happen in 50 or 100 years. So it's essential that we monitor the marine environment to make sure we're not polluting it,'' he said.

Toxic ash, however, can be reduced to a minimum by controlling what goes in the incinerator. "By instituting good measures, we'll not only reduce the volume of ash but the amount of toxins in the ash,'' said Dr. Smith.

Bermuda's not alone in its decision to discard incinerator ash in the ocean.

"We're riding on the strength of other people's work -- especially researchers in Long Island, New York,'' said Dr. Smith. "And quite a few other places are adopting this technology.'' Eventually cement-stabilised ash could create land -- depending on the way it's placed in the water -- and ultimately be a valuable asset to the Island.

TESTING TIMES -- Dr. Robbie Smith experiments with incinerator ash mixed in concrete blocks to see if they will affect the marine environment.