Shafts in Gubkin Mine, KMAruda have been in operation since the late 1940s. The shafts are sunk in difficult hydrogeological conditions. At the present time, due to transition to deeper levels, deeper mine dumps are required. It is necessary to reinforce shaft lining in watered rocks. During long-term service of shaft 1, due to corrosion, thickness of liner plates and horizontal ribs has decreased by 1.5–2 and 3–5 mm, respectively (two-side corrosion). As a result, the load-bearing capacity of the tubbing has lowered by 5–7%. At the same time, the actual stresses are not higher than 22 MPa, which is 10 times less than the design compression resistance of gray cast iron as per Construction Code SP 16.13330.2017. Field studies have been performed in Gubkin Mine toward improvement of operating safety of shafts during mineral mining at deeper levels. Stress state diagnostics of lining in shaft 1 shows that the lining preserves its load-bearing capacity in all types of rocks. Thus, safe operation can be continued without extra expenses connected with the lining reinforcement. The field studies in the cage shaft show that pressure on the lining in frozen rocks is 1.5–2 times higher than the design values. It is recommended to continue the studies to estimate effects of possible rock displacements on the lining during further mining.