Igammon: The iceroad is built over rivers, lakes and tundra. Some river and lake areas the ice is grounded; so in those areas all that is really required is to remove the snow. Where the road is built on ungrounded ice then we must thicken the ice by mixing snow and water into a slurry, which then freezes. On some of the river crossings, which have water underneath, the ice must be 12 feet thick to support the drill rig (the rig we moved in here 2 years ago weighed 2.5 million lbs.). The construction of the road (width and ice depth) is based on which drill rig will be used for that year’s program. Where the road is built over the tundra, those areas we have to pre-pack the snow over the tundra, which drives the frost into the tundra. Pre-packing is done with Tucker Sno-Cats and drags so as not to damage the tundra. If we don’t first drive the frost into the tundra it would be like building an ice road over peat moss (extremely unstable). Using GPS coordinates thermistors probes are put in the tundra every few miles and they are used to record the temperatures in the tundra and determine when it is safe to start building the iceroad over the tundra. Dept. of Natural Resources (DNR) keeps track of these temperatures and frost depths and they give the clearance to go or not go. Once the frost is deep enough and clearance is given then the first thing is to ice in the bottom layers of snow that are naturally present on the tundra by flooding them with water. Then using snow and water we start building up the layers to smooth out the top. During the construction phase all snow, ice chips and water is hauled using Caterpillar and Volvo Articulated Trucks. During the final top coating (paving phase) conventional and artic water trucks are used. So BDFT has it just about right; we use the snow in other areas to build up the road and to build ramps up off the rivers and lakes, but we can’t just use snow alone. We mix it with water to form ice. In the areas where we don’t use snow then we grind the surface of the lakes using roto-mills and make ice chips. We are regulated by DNR as to how much water and ice chips we can take from each lake. In regards to your berm comment; berms or windrows up here are a bad deal. With all the blowing snow and wind any berm causes drifting and any drift can quickly get out of hand and plug the road with snow. Any time we clear the road we always use snow blowers so as not to form any berm close to the road.
I hope this helps you to understand some of the process.
Regards, Randy
