Any person who, without a license, takes quahaugs by dredge, or any person who violates any suspension of the director of environmental management made with respect to quahaug dredging or who violates any provisions of this chapter for which a penalty is not otherwise provided, shall, upon conviction for the first offense, be fined two hundred fifty dollars ($250) and the director may seize, hold, and impound, at the owner’s expense, in one of three (3) commercial shipyards submitting the lowest bid, for a period of not less than thirty (30) days nor more than sixty (60) days, any power boat used in the violation of this section together with its dredges, rakes, and equipment. Any person convicted of a subsequent violation, or violations, of the provisions of this section shall be imprisoned for thirty (30) days and the director of environmental management may seize, hold, and impound, at the owner’s expense, in a commercial shipyard for a period of not less than ninety (90) nor more than one hundred twenty (120) days, any power boat used in the violation of this chapter together with its dredges, rakes, and equipment.