The vote was 4-3 in favor of his appointment with council members Brad Koplinski, Eugenia Smith and President Wanda Williams voting against the move.
Mendez-Saldivia, who comes from the Miami area, is being paid $110,000 annually. The position was part of the recovery plan crafted by former receiver David Unkovic.
The council had refused to approve the appointment after Unkovic resigned. A hearing for Unkovic's replacement, retired United States Air Force Maj. Gen. William B. Lynch, will be held Thursday in Commonwealth Court.
The council will be represented at the hearing by Montgomery County attorney Mark Schwartz, who will be paid no more than $2,500. Schwartz has represented the council since it petitioned for bankruptcy protection in the fall.
Smith and Williams said their vote Tuesday was not personal. They said they wanted to learn more about why Unkovic resigned before confirming a COO, or business administrator and chief of staff.
Unkovic resigned the position in late March, citing "political and ethical crosswinds."
Harrisburg carries more than $326 million of incinerator debt, said Steven Kratz, a spokesman for the state Department of Community and Economic Development. When the city entered Act 47 in December 2010, the debt was $288 million.
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