Oil and tar that leaked from an off-shore storage tanker almost two weeks ago continues to wash up on beaches in Wyre, the council said.
Although the clean-up operation has ended in Blackpool, specialists are still working to remove clumps of thick substance in the borough, mainly at Knott End, The Gazette understands.
Some 15 tonnes of waste, including oil, sand, and stone have been removed in Wyre since early last week, while four tonnes have been collected at Bispham and Blackpool.
The Fleetwood to Knott End ferry service remains suspended because the slipway is too treacherous, while the slip is also closed for boats and jet ski access.
The shellfish beds at Knott Spit and Sea Centre South in Knott End also remain closed.
"The tide continues to wash up more oil and tar which we are removing with the help of specialist oil pollution contractors," a spokesman for Wyre Council said this morning.
"We are concentrating the clean up operation Over Wyre, which is the worst affected area, and also have officers monitoring Cleveleys, Rossall and Fleetwood beaches."
The clear up began last Sunday, when oil washed up at Bispham in what was initially described as a 'small' problem by the Coastguard service.
It escalated the following day when oil began washing up as far south as the mirror ball in Blackpool, and as far north as the River Wyre.
The oil giant said between two and 20 tonnes of oil leaked there last Monday, and said it informed authorities 'immediately'.
A specialist group has been set up to monitor any impact on marine and wildlife, though there have been no reports of any as yet. One expert said the effect could be devastating.