The plant was last inspected by
OSHA in 1985. At the time, according to records obtained by the
Associated Press, OSHA cited the plant for improper storage of
anhydrous ammonia and fined it $30; OSHA could have imposed a fine of as much as $1,000. OSHA also cited the plant for violations of respiratory protection standards, but did not issue fines.
[10]
After a complaint in 2006 about an ammonia smell coming from the facility,
Texas Commission on Environmental Quality investigated and cited the operator for not having obtained a permit for its two storage tanks containing anhydrous ammonia. A permit was issued once the operators brought the facility into accord with the regulations and recommendations made by the agency.
[11][12]
According to an open records request by
Reuters, the plant had a long history of thefts, mostly by people wanting to use the anhydrous ammonia on site to make
methamphetamine. Despite this, the plant had no security guards or burglar alarms, and didn't even have a surveillance system until 2009.
[13]
At the time of the explosion, the facility had a permit to store nearly 54,000 pounds (27 short tons; 24 t) of anhydrous ammonia.
[8] Despite this, company officials filed an emergency planning report with the
EPA stating there was no fire risk or explosion hazard involved at the plant.
[14][15]
According to a filing with the EPA in late 2012, the company stated that it stored 540,000 pounds (270 short tons; 240 t) of ammonium nitrate and 110,000 pounds (55 short tons; 50 t) of anhydrous ammonia on the site.
[16] However,
Homeland Security Secretary Janet Napolitano told
Senate investigators that the company hadn't disclosed its ammonium nitrate stock to her department. Federal law requires the
Department of Homeland Security (DHS) to be notified whenever anyone has more than 1 ton of ammonium nitrate on hand, or 400 pounds if the ammonium nitrate is combined with combustible material.
[13][17]