TORRANCE (CBSLA.com) — ExxonMobil says they will re-start a Torrance refinery Monday, after deciding over the weekend to postpone the event.

Company executives told Southland air-quality regulators about the postponement Friday, citing unexpected operational delays.

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ExxonMobil had already begun notifying about 11,000 residences and businesses near the refinery of the planned re-start, which was expected to occur between 7 p.m. Saturday and 7 a.m. Sunday.

As a precaution, ExxonMobil will shut down a pollution control device for six hours during the 12-hour overnight period, from 7 p.m. Monday to 7 a.m. Tuesday. That shutdown will result in up to 600 pounds of excess particulate emissions, but AQMD staff do not expect it to expose residents to unhealthy levels.

“We are taking a number of steps to protect nearby residents when the refinery starts up and resumes operations,” said Wayne Nastri, acting executive officer of the AQMD. “One of those measures includes deploying an air monitoring network to measure fine particulate levels in the air around the refinery during the startup process.”

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ExxonMobil officials said the restrictions imposed by the AQMD on the operation will “minimize impact to the community and the environment as we resume full operations.”

The refinery has been largely out of operation since Feb. 18, 2015, when an explosion caused extensive damage to the facility, injured four people and led to spikes in Southern California gas prices.

Under the re-start agreement approved by the AQMD hearing board, ExxonMobil must pay about $5 million in penalties for air pollution violations that resulted from the February 2015 blast.

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