Mill the grains and mix with 3.3 gallons (12.4 liters) of 163°F (73°C) strike water to reach mash temperature of 152°F (67°C). Hold the temperature for 60 minutes. Vorlauf until the runnings are clear, then run off into kettle. Sparge the grains with 4 gallons (15 liters) and top up as necessary to obtain 6 gallons (23 liters) of wort. Boil for 60 minutes, adding hops and lactose according to the schedule. Stir the lactose until completely dissolved. Chill the wort to slightly below fermentation temperature, about 60°F (16°C). Aerate with pure oxygen or filtered air and pitch the yeast. Ferment at 60°F (16°C) for 7 days, then allow temperature to rise to 70°F (21°C) and hold for 3–4 days. Upon completion of fermentation, crash to 35°F (2°C), then bottle or keg and carbonate to approximately 1.75 volumes.