Petuna's hatchery in Cressy can be upgraded in an environmentally sustainable and acceptable manner, Environment Protection Authority chair Andrew Paul announced on Wednesday.
The proposed development will see a third recirculating aquaculture system added to the hatchery, allowing for more salmon to move from flow-through ponds to the controlled environment of the system.
Existing flow-through ponds will also be partially reconfigured to provide more space for wastewater treatment.
Mr Paul said the EPA had considered several environmental issues, including the quality of effluent discharged to Brumbys Creek and the levels of wastewater treatment from the flow-through and recirculating systems.
"The use of a third recirculating system at Cressy means a significant proportion of biomass on the site can be moved from the existing flow-through ponds, where there is minimal treatment of wastewater, to the more controlled environment of a RAS where water is reused and treated prior to discharge," Mr Paul said in a statement.
Conditions have been imposed requiring regular monitoring and reporting of water flow and quality at a number of locations both within the hatchery and upstream and downstream of the hatchery, the EPA chair added.
"The proposed upgrades will also cause a doubling in the volume of solid wastes being removed from wastewaters during treatment and requiring removal from the hatchery," Mr Paul said.
"Requirements in the licence have been included which are intended to manage risks associated with odours, and for the longer term management of sludge generation from wastewater treatment."