The Environmental Protection Agency is working to remove hundreds of containers of hazardous chemicals from a Craftsman home in Seattle's Green Lake neighborhood.
The EPA said it first learned of the chemical containers on March 25 from King County officials. Fire crews responding to a 911 call at the house noticed the chemicals and alerted the EPA. Agency experts visited the property a few days later and said the home could have more than a thousand containers, of various sizes, both inside and outside of the home.
Many of the chemicals were stored in food jars and juice jugs. Some of the metal containers were rusted.
Officials say the substances could pose a substantial threat to public health and the environment if released. The EPA found arsenic; carbon tetrachloride, a potential carcinogen; sodium hydroxide, which may react with water to generate sufficient heat to ignite combustible materials; and different acids which can cause severe burns.
Some of the chemicals posed a fire hazard, although the EPA also noted that many of them were so old they had lost their potency.
The owners — an elderly brother and sister — have been relocated while responders work to clean up the site. One of the property owners had a background as a research chemist.
"He just seemed to be — maybe get over-involved in collecting and stockpiling all these chemicals," said Jeffrey Rodin, who is with the agency's emergency response unit.
Attempts to contact the homeowners were not successful on Wednesday.
The cleanup is expected to take until next week. On Wednesday, a worker repaired the home's front steps so crews could enter safely. Chemical detection devices around the site sniffed the air for harmful chemical releases and sounded no alarms.
The EPA says the costs of removing the chemicals could be $125,000. The agency generally does not try to recover cleanup costs from homeowners.
Editor's note 4/17/2014: This story has been modified to clarify concerns over sodium hydroxide. EPA documents said sodium hydroxide may react with water to cause spontaneous combustion. When asked to clarify they later stated sodium hydroxide may react with water to generate sufficient heat to ignite combustible materials. This story now includes that clarification.