As many as 500 Scottish mining jobs are to be saved after five open-cast sites abandoned in the wake of the collapse of Scottish Coal were handed over to a new company.

Mining operator Hargreaves is to give them a lease of life following the deal, but questions remain about the restitution of the landscape in other sites across the country.

The sites to be re-opened with the immediate saving of 300 jobs are at Broken Cross in South Lanarkshire and House of Water and Chalmerston in East Ayrshire, while restoration work will be carried out at Damside in North Lanarkshire and St Ninians in Fife.

But it leaves the restoration of some two dozen sites across the country in doubt. Scottish Liberal Democrat leader Willie Rennie was critical of the deal between Hargreaves and the liquidators of Scottish Coal and its subsidiary Castlebridge Plant, claiming: "Although it is helpful to see some of the sites bought and jobs secured I am disappointed Hargreaves have opted to cherry-pick the sites they want and dump the rest."

"It is imperative the Scottish Government agrees to a public inquiry to get to the bottom of what went wrong and the conduct of the industry. [Energy] Minister Fergus Ewing must now see we desperately need that inquiry, as I fear we are simply building on the mistakes of the past rather than learning from them."

However, Mr Ewing insisted: "The news today that Hargreaves Plc are to assume operation of five former sites, leading to the recovery of 300 jobs increasing over time to 500 jobs in the coal industry in Scotland, is very welcome news.

"As chairman of the taskforce I have appreciated the unstinting contribution that Hargreaves have made towards securing its aims."

The minister said he had met some of those made redundant following April's collapse of Scottish Coal, and described them as highly skilled, hard-working people who just want to get back to work. "This is all positive activity and we are heading in the right direction to secure the future of this industry and the restoration of sites," he said.

"In addition to the commitment to restore these sites, Hargreaves have indicated that they intend to invest a further £25 million in the coal industry in Scotland. This is a substantial and very welcome investment."

He said work in the coming months to tackle the challenges of restoration would further protect jobs in the sector.

"The taskforce will meet again in September and will continue in collaboration with stakeholders to ensure that together we secure the optimum outcome for all concerned," he said.

Iain Cockburn, group finance director of Hargreaves Services Plc, said: "It has taken a lot of hard work by many stakeholders to reach this agreement, given the complexities involved following the collapse of Scottish Coal, and today's announcement marks a new start for coal production in Scotland, creating the opportunity for 300 much-needed mining jobs in the next three months and up to 500 as production increases.

"Today's agreement also provides wider development and regeneration opportunities to help address the legacy of unfulfilled restoration obligations. We will work collaboratively with our local communities, key stake- holders and regulators."

Aedan Smith, of conversation charity RSPB Scotland, said: "We need clear guarantees that restoration will actually happen. This industry has let us down badly in the past, with revelations that restoration bonds were tens of millions short of what was needed, and we are far from convinced that this will not happen again."