Goodlettsville, Tenn. -- Dollar General Corp. is not sitting back while rivals Family Dollar and Dollar Tree prepare to merge. Following its failed bid to acquire Family Dollar, Dollar General has accelerated its expansion plans for 2015. The discounter, which already has the retail industry’s most aggressive new store strategy said it will open 730 new stores and remodel 875 existing locations in 2015, translating into a 6% increase in total square footage. And looking ahead, Dollar General plans to grow its square footage by 7% in 2016.