COLUMBIA — Taxpayer concerns about last fall’s hacking of a South Carolina state agency are expected to lead to fewer online tax filings, potentially adding several hundred thousand dollars to the debacle’s nearly $22 million price tag.

While insisting that it is safe to e-file, Department of Revenue officials are preparing for concerned taxpayers opting for the more time-consuming paper route.

“We envision we’ll have to hire part-time people with more paper files coming in,” interim Director Bill Blume said after a recent hearing before a Senate panel.

On Friday, the agency estimated needing 25 part-time workers to key in information, though spokeswoman Samantha Cheek stressed that the exact number will depend on the number of paper returns filed. She noted that 2013 processing has just begun.

Under current projections, the agency expects to spend an additional $300,000 to $400,000 on paper processing. Beyond the two dozen employees, costs include additional postage, paper and printing of correspondence, Cheek said.

“We hope to see individuals continue to choose electronic filing, as it is the most efficient for both the taxpayer and DOR,” she said.