In a costly hiccup for Pomona Valley Hospital Medical Center, the Los Angeles-based institution has agreed to cough up almost $2.1 million in a settlement over accusations of Medi-Cal overbilling. The Justice Department made the announcement today, putting a price on errors made in prescription medication charges. According to the settlement agreement released on Wednesday, this hefty sum is the consequence of a self-reported blunder, where the hospital overcharged a federal drug pricing program for five years.