Over 140 people have called for planning permission for a mast in Rossmore Park to be refused.
Cignal Infrastructure is intending to build a 39 metre mobile and broadband tower on the Coillte-owned land.
The application was submitted at the end of March, with the applicant previously saying the areas around the Monaghan town forest had been identified as coverage blackspots.
It added it was committed to an open dialogue with local residents to explain the plans.
23 submissions have been received by Monaghan County Council in objection to the plans.
This includes two local councillors, nearby businesses, residents of adjacent Traveller accommodation, the Friends of Rossmore Park group and a residents association representing 121 people.
In 150 pages of submissions, it was questioned if the development was in itself needed, and if the height and precise location was also required.
Concern was also raised about the potential health impacts of such a mast operating so close to residential areas and business premises, as well as the impact it will have on the value of nearby properties.
Members of the Traveller community said Cellnex Ireland didn't inform them of the plans in ways they would understand and that it will be distressing to them to have a mast less than 200 meters from their homes.
Other submissions opposed it on the basis of the visual impact it could have on the local landscape, and how the site notices were displayed.
A decision on the application is due on Tuesday.
