An engineering problem, while being eaten by bugs

The erosion and slumping at Walakpa had left a large overhanging of sod, which was putting a lot of weight on the exposed house structure.  The weight had already caused a crack in the sod on the surface up on the top of the site, and I was pretty worried that the whole thing could fall.  We wanted to get that overhang cut back flush with the bluff.  It was really hard to get to it, and we couldn’t just use shovels to cut the sod off, since there was nowhere to stand that didn’t risk knocking the whole thing down.  It was more of an engineering problem than a regular excavation.  We trimmed some of it off from below, standing on either side of the house, while others worked from on top.

Early stages of cutting back the overhang
Early stages of cutting back the overhang

The overhanging sod had seemed pretty thin, but it had apparently lost some soil off the bottom, since it proved to be over 30 cm (about 1 foot) thick when we cut into it.  Getting all that heavy wet sod off reduced the weight on the structure

Overhang removed
Overhang mostly removed

Once that was taken care of, we moved on to trying to strip the sod from the top of the house back about 1.5 meters (5 feet) from the bluff, so we can begin excavating the house.  Trina Brower & I did surface topos of the north half of the mound with the total station, and then we started.  We still couldn’t use a shovel along the edge, since the crack went too deep, so we started away from the bluff.  We hadn’t gotten very far when some buried Visqueen showed up!

Initial sod cut, with VIsqueen showing at the south end.
Initial sod cut, with VIsqueen showing at the south end.

Obviously, everything above the Visqueen is quite recent and can just be set aside for re-sodding the site.  As far as I can tell from the profile, it is all a redeposited layer, maybe from Dennis Stanford‘s nearby excavations.  Anne Garland is trying to excavate the Visqueen out, so we can at least get a surface that was exposed prior to the deposit of the plastic, and maybe figure out if this is an old test unit or something else.  My husband Glenn has vague recollections of a group from the Utkiavik Project hiking to Walakpa and backfilling some disturbances they found, and using Visqueen in the process, so this may be from that.

On Friday, we had a cameraman from PBS along.  PBS is in Barrow interviewing a number of scientists (and some other folks) for a program they are doing on sea ice retreat.  That is part of the reason why sites are eroding so fast up here.  They wanted to interview me about the Nuvuk Archaeological Project.  They had already planned to go out to the point with another scientist, and since we aren’t digging there this summer (it was supposed to be all lab work), it didn’t seem to be that useful to go again.  So we discussed going to Walakpa so they had something to film, and it was also a good example of the issues that arise from sea ice retreat.  It was terribly buggy the last few days, which made for some unpleasant working conditions.  It was quite difficult not to swat mosquitoes for the entire interview, but apparently I did OK.  We had to shoot a bit more in the lab on Saturday, due to changing light in the field (and the fact the producer had caught a stomach bug on the way to Barrow and wasn’t able to leave her room, let alone go to Walakpa).  I think I was able to make some points about how retreating sea ice increases coastal erosion and what we lose when that happens.  We will see what if anything makes it through the editing.

Even if it was buggy, Walakpa was still pretty.

Walkapa Lagoon looking inland from the site.
Walakpa Lagoon looking inland from the site.
Looking at the eroding house from the total station.
Looking west at the eroding house from the total station while doing surface topo.  Anne Garland in yellow on the bluff edge, and Trina Brower with the stadia rod.

 

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