Rinse the smelts in cool running water. Set aside.
Place all of the remaining ingredients, except the ice, into an electric kettle. Bring to a boil. Add the ice and stir until the mixture is cooled. Transfer the liquid to a 1-gallon resealable bag along with the smelts. Seal and place in a container so that all of the fish are covered by the brine. Place in the refrigerator for 30 minutes to 1 hour.
Remove the smelts from the brine, rinse, and pat dry. Place the smelts onto a paper towel-lined half-sheet pan, layering with paper towels if they won't fit in one layer. Allow to dry in the refrigerator overnight.
The next day, place the smelts onto racks, belly-side down, separating them by at least 1/4 inch and place into a smoker. Turn the smoker on so that it maintains a temperature of 150 to 160ºF. Adjust heat, as needed, and cook for approximately 3 hours or until desired level of doneness.