An investigation into a crude oil spill in Bastrop County that discharged more than 87,000 gallons will examine the circumstances surrounding the accident as well as review the resulting cleanup, state Rep. John Cyrier said Monday.

The representative’s announcement is the first time officials have mentioned a "substantial increase" in the reported volume of crude oil spilled along FM 20, just south of Shiloh Road, on July 13. Initially, Magellan Midstream Partners, which owns the pipeline, reported 1,457 barrels spilled, or about 50,000 gallons.

On Monday, Cyrier said new estimates indicate the Longhorn pipeline, which carries crude oil from the Permian Basin in West Texas to Houston, released 2,084 barrels of oil or 87,528 gallons. "This is a substantial increase from earlier reports," Cyrier said.

Thomas Byers, a spokesperson for Magellan, said Tuesday the initial oil spill volume reported to state and federal authorities was the company’s best estimate at the time the information was provided. He said the new estimates were gathered after the pipeline was fixed and allowed to gradually return its operation.

"The refilling and repacking of the pipeline is first conducted to ensure the integrity of the pipeline and to confirm that proper repairs were made. Static pressures are monitored and analyzed before the pipeline is allowed to gradually return to operational status," Byers said. "Technical analysis of the data collected includes final calculations of volumes added to refill the line. Management review and approval of the final calculations typically occurs a few days after the line is returned to service."

Byers said Magellan and its environmental experts are continuing the cleanup process and will continue to do so for as long as necessary. The company has maintained that the crude oil spill has not impacted any water source in Bastrop County.

The oil spill occurred when one of Magellan’s excavators hit the pipeline while conducting routine maintenance. Following the rupture, officials closed the roadway for about 24 hours as crews worked to contain the spill and begin cleanup efforts. Fifteen families with homes nearby were evacuated to emergency shelters but were allowed to return to their houses the same day.

The damaged portion of the pipeline was repaired in a couple days and it resumed normal operations on July 16.

The soil that was contaminated from the spill zone has been removed and is being shipped to a landfill equipped to handle hazardous waste, officials said.

Cyrier said the Railroad Commission as well as the Texas Commission on Environmental Quality are continuing to monitor the site and are providing updates on the progress of the cleanup.