The board of ATH subsidiary Aardvark TMV, which has its opencast mining operations in Scotland, has decided to voluntarily wind up the business and appoint KPMG as joint liquidators.
Hargreaves, also preferred bidder for Scottish Coal's assets, had previously acquired ATH's debt from private equity firm Better Capital through subsidiary Hargreaves Surface Mining (HSM).
The deal for the Aardvark assets was said to have been met through a combination of cash and settlement against the secured debt which amounted to £13.1m.
HSM also has an agreement in place to buy the Netherton and Duncanziemere mines in Ayrshire, although they will remain owned by Aardvark until discussions on outstanding restoration liabilities are resolved. Until then HSM will provide mining services and sell the coal produced.
A similar agreement has been struck with Buccleuch Estates to provide restoration and mining services at Glenmuckloch, near New Cumnock in Ayrshire, with operations expected to start in the early summer.
Durham-based Hargreaves expects to produce one million tonnes of coal in Scotland in its next financial year.
It signalled it is planning to make further acquisitions of plant and equipment in the coming weeks and is looking at a number of other sites.
Aardvark also has further sites in Ayrshire plus one in Fife while ATH had its headquarters in Doncaster.
Gordon Banham, Hargreaves chief executive, said the company will use the staff and operations acquired to "continue to invest in developing a profitable and sustainable surface mining business in Scotland".