A clean up company started evaluating a Plum Creek neighborhood home Monday morning after it was condemned when Castle Rock police officers found explosive devices inside on Halloween.

Professional decontamination is required before the residents are allowed to move back.

Environmental Testing Company based in Parker is doing an initial assessment before a hazardous material company will remove the chemicals.

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Unknown chemicals in the home on West Prestwick Way were found in glass beakers and jugs. Firefighters said combined, they could be deadly.

When it comes to clean up, hiring the company and paying for the work is the responsibility of the homeowner. When that is completed and approved by the fire department, the family will be able to move back.

The cost could go as high as $10,000.

Since firefighters and clean-up crews don't know what the chemicals are, everything needs to be tested, logged, decontaminated and throw away at a hazardous waste landfill. That could take anywhere from one to four weeks.