Ark. Code Ann. § 14-116-604

If such owner has been given notice by certified mail posted at least thirty (30) days prior to the date of the hearing provided for in § 14-116-603, he shall be construed to have accepted the assessment of damages in his favor made by the assessor or to have acquiesced in the failure to assess damages in his favor unless he gives to the court clerk, not later than the date of the hearing provided for in § 14-116-603, notice in writing that he demands a reassessment of his damages. In this event, the board shall institute an action to condemn the land that will be taken or damaged in carrying out the works of improvement included in the improvement plan.