Washington, DC, April 1, 2005, 7 p.m. Eastern time - A team of three U.S. Chemical Safety and Hazard Investigation Board (CSB) investigators entered the BP Texas City refinery isomerization unit for the first time today since the March 23 explosion. The team consisted of Investigation Manager Bill Hoyle, the lead investigator; Investigation Manager Stephen Selk, PE, a chemical engineer; and Investigator John Vorderbrueggen, PE, a mechanical engineer.

Investigators remained in the area for approximately three hours using respirators as well as fire and biohazard protective clothing, including Nomex suits, rubber boots, and gloves. Air-purifying respirators were used to protect against residual benzene vapors. The CSB team was assisted by a BP operator familiar with the isomerization unit. Investigators took approximately 200 photographs in the course of their examination.

Investigation Manager Bill Hoyle issued the following statement: "The isomerization unit equipment is structurally intact for the most part, but calcium silicate insulation and metal cladding litter the area and also dangle overhead. Some areas of the isomerization unit remain unsafe for entry.

"The CSB team inspected the blowdown drum connected to the atmospheric vent stack where the release is believed to have occurred. That drum is an approximately 10-foot-diameter, 20-foot-high vessel that receives hydrocarbons vented from the raffinate splitter and other equipment. We ascertained and documented the position of critical valves on the blowdown drum and other unit equipment. Adjacent and to the west of the isomerization unit is an area of debris where trailers were located at the time of the explosion.

"In the area of debris, we found the demolished remnants of approximately 6 to 10 trailers and about 30 vehicles, including cars and trucks. It is unknown how many vehicles may have been running when the vapor cloud was released from the vent stack. The vehicles and trailers exhibit heavy blast damage, and investigators have not been able to positively identify a diesel pickup truck described by eyewitnesses as over-revving moments before the explosion. Remains of several vehicles were located within 25 yards of the vent stack."

Some CSB investigators are returning to Washington, DC, on Friday afternoon; others will remain in place over the weekend and continue to examine the explosion site. Hoyle said the site examination will be an important component of the CSB's root-cause investigation, together with witness interviews and reviews of applicable regulations, standards, and company procedures and records. A full CSB team will return to Texas City on Monday, April 4.

Media inquiries should be directed to Dr. Daniel Horowitz, CSB Director of Public Affairs, at (202) 261-7613 / (202) 441-6074 cell. No press statements or media availabilities are planned over the weekend.