For example, the facility at Pitsea in Britain, on the banks of the River Thames near London, accepts only solid municipal and commercial waste, because European law prohibits the mingling of liquid and solid waste, and of hazardous and non-hazardous waste.

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While the Environmental Protection Agency would prefer to regulate the byproduct that contains arsenic, mercury and lead under stricter federal hazardous waste laws, the utility sector wants it to remain classified as a solid waste that the states now oversee.

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