According to the
federal government is encouraging farmers to spread a chalky waste from coal-fired power plants
on their fields to loosen and
fertilize soil even as it considers regulating coal wastes for the first time.
The material is produced by power plant "scrubbers" that remove acid rain
causing sulfur dioxide from plant emissions.
A synthetic form of the mineral gypsum, it also contains mercury, arsenic, lead
and other heavy metals
. The U.S. Environmental Protection Agency
says those toxic metals
occur in only tiny amounts that pose no
threat to crops, surface water or humans. But some environmentalists say too
little is known about how the material affects crops, and ultimately human
health, for the government to suggest that farmers use it on their land. The
EPA is expected to announce its proposals for regulation early next year,
setting the first federal standards for storage and disposal of coal wastes.
EPA officials declined to talk about the agency''s promotion of FGD gypsum before
then and wouldn''t say whether the draft rule would cover it. Instead, the
agency released a statement saying the heavy metals
in the material are far less than the amount considered a threat to human
health. Field studies have shown that mercury, the main heavy metal of concern
because it can damage development of the human nervous
, doesn''t accumulate in crops or run off fields in surface water
at "significant" levels, it said.