Adroit took over the site in May after it fell in to disrepair following an ill-fated attempt to stage the British Grand Prix by the previous owners.
The contractor started relaying the track immediately and it passed a crucial safety inspection by the motorsport authorities earlier this month.
The track hosted a three-day classic motorcycle race this weekend which involved 400 bikes.
David Broome, managing director of Adroit Group, said: “We intend to bring the site back up to a world class standard.
“The entire site needed attention whilst much of it required a total overhaul from the track itself to the medical centre, hospitality suites, phone, radio and PA systems, IT systems, CCTV and general ground work.
“Through a calm, cautious, credible and sensible approach we know that we have the experience, expertise and absolute commitment to bring the glory years back to Donington.”