AUSTIN, Texas -- The Houston-based barge operator that spilled nearly 170,000 gallons of tar-like oil into one of the nation's busiest seaports will be fined by Texas regulators, regardless of the outcome of state or federal investigations.

Investigators are still trying to pinpoint the cause of last weekend's accident in the Houston Ship Channel.

But the Texas General Land Office says Kirby Inland Marine Corp., which owns the barge, will be penalized because state law considers the company carrying the oil a responsible party.

State records show that the company has been fined more than $51,000 for at least 77 spills since 2008, most of which were minor incidents.

The channel was fully reopened late Thursday. It typically handles 70 ships and hundreds of tugboats and barges each day.