More than 1,000 people have written to the Department of the Economy in the North to oppose the granting of a licence for fracking in the Fermanagh Lakelands.
The process uses a combination of drilling, blasting, and pumping a chemical slurry to release natural gas from shale rock.
It comes five years after Tamboran Resources had its first application to drill in south Fermanagh turned down.
Scott Coombs from the Love Leitrim group said fracking is linked with serious health concerns in the United States.
Mr Coombs said: "The concerned health professionals in New York issued their sixth compendium of fracking research in the United States in June.
"Now this latest compendium has 1,500 peer-reviewed studies, journalism, government reports - and they all show undeniable links between fracking activity and public health concerns."