Four sites have been shortlisted for a new girls' secondary school in Tuam, Co Galway.
However, the Department of Education is not disclosing the location of the sites because of "commercial sensitivity".
The school will cater for more than 700 students after the planned amalgamation of the Presentation College, Currylea, and Mercy Convent.
However, numbers attending may rise considerably given the amount of new homes built in the town over recent years and large number of new families who have moved into the area.
Even the current enrolment for the two schools is closer to 800 pupils.
Tuam is also to get a new amalgamated boys secondary school from the joining of the existing St Jarlath's College and St Patrick's College.
This new school will be located on the site of St Jarlath's College and will involve the refurbishment and extension of the existing school, which was founded over 200 years ago.
The rationalisation of the four secondary schools into one boys and one girls school, excluding the co-ed Tuam Vocational School, was agreed nearly four years ago but the plans haven't significantly progressed until now.
The Office of Public Works, which acts on behalf of the Department of Education in relation to site acquisition, has now identified four possible sites for the new girls school.
A spokesperson for the Department said that a report on these sites is currently being examined by officials.
The OPW says the sites have been technically assessed and they are in the process of assessing the valuation figures.
It is not known whether the two existing girls school sites are included in the shortlist of possible sites.
The Department's spokesperson said that because of the commercial sensitivities of site acquisitions it is not proposed at this stage to identify the sites.
The Department states that a review of all projects, which were not part of this year's School Building Programme, is currently under way with a view to including them as part of a multi-annual programme from 2005, details of which will be announced later in the year.
"The projects for Tuam, together with the procurement process of sites, will be considered in the context of this review," the Department spokesperson said.