GrIT Situation Report 2

March 13, 2016GrIT_logo_2016 SCAT UPDATE

The SCAT team has continued to make good progress.  They started on their overnight trips into the Crevasse Zone March 7th, setting up their first camp at the B3 area, and moving just a few days later to B5a.  When camping, they take along their living modules, which provide berthing, cooking facilities and heated shelter.  The Crew Quarters has solar power capability; however, at this time of year, the sun angle is so low that the solar panels mounted on the top of the roof don’t fully charge. So the SCAT team relies on non-renewable energy sources as well.  The Crew Quarters has bunks for four people, a kitchen and dining area, and a shower room.  It is akin to an RV, but is missing the pop-out living room.

Once a route is found, hauling heavy loads through the crevasse zone is still a difficult task. Hills require ‘double hauling’—attaching two tractors to a load of cargo to pull it uphill, and  connecting  a tractor in the back to keep a cargo load from gaining too much speed on the downhills. In addition, part of the route goes along the side of a hill, requiring extra vigilance to prevent cargo from tipping.

One of the sleds we have to haul this year is intended to provide a moveable base for a mobile science structure at Summit.  The sled has been named the ‘Smobile’ (Small Mobile) sled and was delivered to Thule via cargo ship last summer from Norfolk, VA.  At Summit, the sled will support the Smobile building, an insulated 14' x 40' multipurpose building  which has been used as a laboratory, berthing, recreation space and a workshop. The Smobile sled is mounted on a more traditional ski base versus GrIT's standard black plastic HMW sheets.  This ski set-up works for short distances around Summit, but it is not as suitable for long hauls through the deeper snow on the ice sheet.  Hauling the Smobile behind our sled train through the crevasse zone could also prove difficult.

GrIT Operator Ben Toth showing Smobile sled's low clearance.

Knowing this, we decided to take advantage of the hauling capacity of the SCAT team and have them move the Smobile sled using their more nimble tractor set-up to eliminate some of the towing weight for the heavily laden GrIT tractors.  We loaded the Smobile with plywood and tractor parts, making it as light to tow as possible (though it still weighed in at nearly 20,000 lbs).  The sled was then staged at the SCAT camp B3, where the SCAT team would pick it up and drop it off after they’d reached the top of the area known on the map as Dog Lady Hill.

SCAT team adjusting GPR boom – mounted on an arm in front of the Tucker, it is our first method of crevasse detection. Photo: Robin Davies

The SCAT team continued forward, and moved to their third camping spot, B6, late in the week. There they staged to begin the tricky B8 section of the route. The B8s have traditionally been heavily crevassed, causing lots of trouble.  This year it seems the area has continued to change, as the SCAT team has come up against some difficult crossings, and started looking NW of the planned route in hopes of finding a safe path through.  They continue to explore forward.

Route view with SCAT camping spots noted.


The team based in Thule has also made great progress getting cargo and sleds ready for transport.  A necessary part of any traverse is fuel, and in our case, we require fuel for our tractors as well as fuel to deliver to Summit Station.  Fuel is hauled via 3000-gallon bladders that ride on top of a black HMW sled.  Each year, we have to inspect each bladder to be sure there are no holes or abrasions that could cause leaking.  The bladders are unwieldy and difficult to store, and they don’t respond well to cold temperatures. Due to our limited storage space, we have to roll them up and keep them in our cold warehouse between use, and this can often cause rubbing/cracking along the seams.

We have found that working with fuel bladders inside heated buildings allows for the best inspection and patching, but heated buildings are at a premium in cold environments.  The Air Force Base has been kind enough to allow us to work inside one of their giant aircraft hangars (a building big enough for a C-17 to park inside), giving us the space needed to lay out and inspect our bladders.

The crews inflated each bladder using a whitewater raft pump, allowed the bladders to sit for several days, and then observed their inflation pressure to identify leaks. They also visually inspected the bladders for holes, and prepared some patches in the warm environment. The true test will come once we haul the bladders to the transition and load them with fuel, but we have to wait for the SCAT team to verify the safe route has been found before that last step can be done.

Julie Raine telling Thule residents about GrIT transport and Air Ride Cargo decks Photo: Allan Delaney

In addition to the work done for the GrIT, the crew invited Thule residents out to see our operations at the edge of the ice sheet. About 100 people visited the transition to see what we have been doing. Many were curious about our tractors and cargo sleds and found our wind/solar-powered emergency shelter quite keen. They also enjoyed walking just over a quarter mile on to the ice sheet via our GPR’d route despite the frigid temperatures and windchill hovering at -23F!

--Julie Raine, GrIT Manager

The Arctic Research Support and Logistics Program within the National Science Foundation’s Division of Polar Programs funds the GrIT.  CH2M HILL Polar Services and Cold Regions Research and Engineering Laboratories are working together with the NSF to develop the traverse infrastructure and route to Summit Station. The 2016 spring traverse delivers fuel and cargo to Summit Station, and continues efforts to optimize mobility, GrIT will provide direct science support to several projects, retrieving instruments for a soon-to-be-completed effort, and laying fuel caches for upcoming projects.