December 24, 2007

Demolition

Experimental demolition method may make asbestos removal safer

Texas city tests ‘wet’ removal

FORT WORTH, TEX.

The city of Forth Worth and the federal Environmental Protection Agency knocked down an asbestos-laden building recently using a controversial “wet” demolition method.

The demolition at the Oak Hollow apartments on the city’s east side was the first test of the new method in a populated area. The city notified the local media about the demolition after work had begun.

A spokesman for a national environmental group called the test “the height of irresponsibility,” but a local politician defended it.

“The tests have been done a couple of times before. If they didn’t feel, from those tests, it was safe to bring into a populated area, they wouldn’t be here,” said city councilman Danny Scarth, whose district includes the building.

Only one building, the complex’s office building, was demolished. The rest of the complex will be taken down using methods already approved by the EPA. Regulations in Ontario allow both methods of removal, with specific safety conditions.

The provincial labour ministry requires three different levels of safety and site preparation for workers on sites with asbestos. From removing parts of a ceiling to demolition, whether using wetted or dry removal methods, different types of respirator apparatus are required.

Recent additions to Ontario’s asbestos regulations included a definition for asbestos-containing material and a new training program for asbestos abatement workers and supervisors.

New and updated requirements for bulk sample analysis, respiratory protection, glove bag operations, use of negative air pressure to prevent dust leakage and air clearance sampling, cleaning and testing have also been put in place.

Health Canada has encouraged provincial occupational health authorities to adopt strict workplace exposure limits for asbestos. It recommends that construction and maintenance workers should avoid creating asbestos dust by scraping, brushing, rubbing or cutting damaged insulation.

In the Texas test, Dave Bary, an EPA spokesman, said the EPA and the Department of State Health Services agreed not to enforce regulations so that the experiment could take place.

That test was the latest in a long-running national debate over how best to demolish asbestos-contaminated structures.

The city wanted to use a similar process to demolish a local hotel in 2005, but called off that project because of concerns from environmentalists and health officials.

The federal government now requires that asbestos be removed from buildings before they are demolished. The alternative method calls for soaking the walls and ceilings with a special foam and tearing down the building with heavy equipment without removing the asbestos. If proven effective, the alternative method would make it much less costly for municipalities across the country to demolish old asbestos-laden buildings that attract crime and lower property values.

Critics have said the new method could allow asbestos fibers into the air, endangering nearby residents. They argued last week that the EPA should move the test to an isolated location. Two previous tests have been conducted in relatively isolated areas in Fort Smith, Ark.

“I think it was the height of irresponsibility to proceed with this human experiment in a populated area,” said John Walke, clean air director for the Natural Resources Defense Council, a national environmental group.

Scott Frost, a trial lawyer associated with Public Justice, said EPA officials’ “only agenda is to get their test results.”

Demolition work began at about 7 a.m. Monday as people nearby walked to school and work. An hour later, an excavator began flattening the building. The EPA had set up rows of air-sampling monitors at the site.

The crews planned to remove about 3 inches of dirt to catch any fibers that soaked into the ground. It would have taken a specially trained crew two days just to remove the asbestos under the old method, said EPA project manager Adele Cardenas Malott.

Terry Lynch, the health hazard administrator for the national asbestos workers union, said there’s no way to know whether any asbestos was released.

DCN News Services

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