Specialist contractors scaled the rock cutting at Aughton Park station in West Lancashire over several weekends.
The work involved removing loose material, inspecting drainage and monitoring the ground conditions on a slope beside the busy railway line.
Rope access teams and engineers carried out the essential safety work while maintaining a 2m distance from each other, in line with government guidelines for essential workers during the COVID-19 pandemic.
Tony Butler, route asset manager for geotechnics at Network Rail, said: "Our teams are working around the clock to make sure people who cannot work from home can still get to their jobs.
"This includes NHS staff who use the railway to get to work in hospitals in Liverpool, Aintree and Ormskirk.
"I'm proud of the hard work our staff continue to deliver, even during this incredibly difficult time."