BP, Valero refineries await return of reliable grid power

Some Texas City refineries and chemical plants continued to limit operations Thursday while the electric utility serving the area worked to resolve drought-related problems on transmission lines.

Although Texas City’s power grid didn’t suffer a repeat Thursday of intermittent power outages that plagued it the three previous days, the massive BP refinery may not have all the outside power it needs until sometime today.

Intermittent power outages Monday, Tuesday and Wednesday caused BP and another refinery operator, Valero, to emit tens of thousands of pounds of sulfur dioxide and other air toxics, according to initial, mandatory reports the companies filed with the Texas Commission on Environmental Quality.

Texas New Mexico Power, which operates the electric grid serving the plants, has blamed the outages on salt and other debris that accumulated on power equipment due to lack of rain that usually washes the material off. The debris can cause lines to short-circuit.

TNMP spokeswoman Cathy Garber said the company is washing the debris from insulators and other equipment, but that the work may require occasional power cutoffs to the refineries as it continues over the next two to three weeks.

CenterPoint Energy, which also serves parts of the area, flew a helicopter with a water cannon Thursday to spray down a power substation on Galveston.

BP said Thursday it still isn’t able to resume all operations at the 473,000-barrel-per-day Texas City refinery and adjacent chemical plant. The complex has its own power generation system, but can’t work at full capacity until it has grid power available as backup, said spokesman Michael Marr.

Valero also was awaiting reliable power connections before restoring its 245,000-barrel-per-day Texas City refinery, spokesman Bill Day said.

Two other plants affected by the power problems — Marathon’s refinery and Dow’s chemical plant – had restored full operations previously.

Winds subdue pollution

High winds helped to mitigate air pollution Tuesday and Wednesday. But a BP monitoring station measured elevated levels of cancer-causing benzene and hydrogen sulfide – a highly toxic chemical that has the odor of rotten eggs – when the average wind speed dipped below 10 mph Wednesday morning.

Neil Carman, air program director for the Sierra Club’s Lone Star chapter, said people can smell hydrogen sulfide at levels as low as 3 parts per billion. The levels reached 98 ppb for about five minutes Wednesday morning, according to BP’s raw data.

TCEQ will not comment on BP’s data until the agency has verified it, spokesman Terry Clawson said.

Some data inaccurate

Already, TCEQ has said its emissions data from Tuesday is inaccurate. It had said levels of volatile organic compounds – a broad class of chemicals found in crude oil, pesticides and common solvents – exceeded the measuring capability of a hand-held monitoring device. But after conferring with the instrument’s manufacturer, the agency invalidated the data.

State Rep. Craig Eiland, D-Galveston, sent letters to the Texas Public Utility Commission and the three power grid operators that serve his district – TNMP, Entergy-Texas and CenterPoint – asking what measures they’re taking to avoid recurrences of the debris accumulation and resulting power outages.

“I know that this is not a new problem or phenomenon during droughts,” Eiland wrote.

tom.fowler@chron.com

matthew.tresaugue@chron.com