St. Paul received a $747,900 grant Thursday from Ramsey County to help pay for cleaning pollution at the site of the new Saints ballpark downtown.

The money will be applied to the $4.25 million balance on a $6 million internal loan that the city made to itself last year when officials found the project was over budget.

Project managers originally estimated that cleaning up the site would cost $5 million. That figure ballooned to $11.2 million last year when borings showed that pollutants had deeply penetrated the soil, requiring more cleaning and stabilization than previously thought.

More than 80 percent of the ballpark’s cost is being paid with public funds. The state is contributing $28 million and a $1 million loan, the city is paying $23.25 million and the Saints are kicking in $2.2 million. The team also will pay off $8.8 million in city bonding with rent payments.

Environmental remediation of the brownfield site, once home to a coal gas manufacturer and a factory, is nearly finished. Construction on the $63 million ballpark began two weeks ago and is expected to be complete in time for opening day in May 2015.

In other City Hall news Thursday, Mayor Chris Coleman named Library Director Kit Hadley to serve as interim planning and economic development director until a permanent director can be hired.

Hadley is replacing Cecile Bedor, whose last day will be May 8.

Hadley, a former commissioner of the Minnesota Housing Finance Agency, will remain as library director while serving as interim planning director.