The company behind the old mine near West Wyalong has lowered its intake of workers to fight the spread of coronavirus.
Evolution Mining Limited said it had designed and implemented "a range of additional site-specific responses" for the Lake Cowal mine, including keeping workers from entering West Wyalong.
The specific Lake Cowal measures will be added on top of company-wide policies to limit face-to-face interaction and promote hand hygiene.
Mine interim general manager Greg Walker said there had been no recorded case of coronavirus for any employee or contractor at Cowal.
"The need to restrict the number of people coming to site will have some impacts to local businesses due to reduced economic activity which is regrettable," he said.
"For example, an upcoming plant shutdown that would have brought more than 65 external contractors into the town has been scaled back.
"One piece of safety-critical electrical maintenance will now be undertaken by a small specialist crew from the Hunter Valley, during a 48-hour period.
Mr Walker said Lake Cowal was following company polices and directions from NSW Health.
"We're doing everything we can to maintain our local procurement expenditure and minimize the impact of COVID-19 on the local community and our people," he said.
"We urge everyone to stay safe and continue to strictly adhere to the advice of NSW Health throughout this challenging period."