Found this:
5-6City Manager.
[Amended 12-11-2006 by Ord. No. 1707]
A.
The City Manager shall be the chief administrative officer of the City of DuBois, appointed by a majority vote of the City Council. He/she shall serve at the discretion of the City. In addition thereto:
(1)
The Manager shall be responsible to direct, supervise and manage the administration of all departments, offices and agencies of the City, except the Volunteer Fire Department, which shall report directly to the Mayor and City Council.
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So looks like the City council can just meet & vote to get rid of him, since he serves at their discretion.