CASEMENT Park could be restored to a working capacity of up to 18,000 spectators at a cost of £1 million.
The refurbishments could be completed without the need for significant additional planning approval, according to Stormont officials.
However, this would not include renovation of the main stand, which would remain sealed off due to safety concerns.
The basic work would allow fans to use concrete seating or stand on terracing.
The long-awaited redevelopment has been recommended for approval by the infrastructure minister in what GAA fans hailed as a "major step forward".
Ulster GAA previously insisted there was no "plan B".
Read More: GAA must cough up more cash for Casement says communities minister
However, a report on the planning recommendation from the Department for Infrastructure (DfI) outlines how the existing venue could be refurbished.
It said that had the new stadium plans been refused, Ulster GAA indicated the existing grounds would be brought back into use.
The GAA project board's position in 2016 was that "if necessary £500,000 could be spent on minor works" which could achieve a safe capacity in the region of 18,000.
Due to further deterioration and rising costs, the conservative estimate was last year increased to £1m.
A report submitted on behalf of the GAA outlined how the majority of the terrace and bleacher areas would be repaired in this scenario.
The main stand would not be reopened under this fall-back position, but would be made available for teams, press facilities and the social club.
DfI's case officer said the majority of the repairs – such as resurfacing, reinstatement of turnstiles, weed removal, fencing, painting, plumbing and electrics – would not require planning approval.
"Those works requiring planning permission are likely to include the replacement of ball-stop nets and their supporting structure and a container to house maintenance equipment," the official said in the report.
"I would view such planning applications as ancillary to the land use of the site and relatively minor proposals which should in principle be capable of approval."
The case officer said they were "satisfied that there is a lawful fall-back capacity for crowds up to 18,000".
This would be of a similar capacity to rugby's Kingspan Stadium and soccer's Windsor Park, although they provide much more covered seating.
The GAA wants Casement to be capable of hosting provincial finals, which can attract more than 30,000.
