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Dave had kindly arranged for and accompanied me on a tour of the larger of the land-bound dredging operation a couple of miles west of town.

Being a life-long “left-coaster,” my sense  of direction was continually challenged by the geography of Nome. The Seward Peninsula juts so far westward from the rest of Alaska that, at it’s extreme, at Point Barrow, a mere 35 miles of water separate it from Siberia. Nome is situated on a coastline that is predominantly south-facing—a difficult thing to reconcile for a person accustomed to seeing the sun set in the west.

Getting a tour of the dredge was a fascinating experience. I’d heard of dredges when, as a youth, my father had told me about them and how they were responsible for the rows of neatly piled rocks still visible in certain places along the Tuolumne River and elsewhere in the Mother Lode region where I grew up.  By the time I’d come along, the dredges were long gone, having been dismantled and hauled off as scrap metal during the Second World War. But I’d never actually seen a dredge before.  

Dredging is, unlike traditional hard-rock mining, a placer operation similar to gold-panning; both seek to retrieve gold that was separated from its native rock by natural forces in prior geological epochs. Gold-mining as employed by dredges such as those in Nome amounted to gold-panning on an industrial scale.

The dredge we toured retrieved gold from the ground by means of a huge conveyor-belt apparatus supported on a derrick and equipped with large bucket-like scoops that were inserted to depths ranging from 50 to 65 feet into the earth to in order to gather up material and bring it to the surface, where it was then sorted with pressurized water in large sluices to separate the gold from the surrounding muck. After the area immediately adjacent to the dredge was worked out, the entire apparatus was moved to a new location where the process began anew.

The dredges were working the same plain the early miners worked in the Gold Rush of 1898, only in those days the gold was reached by tunneling down to the ore-bearing strata hidden some 50-plus feet below. The dredges at times encountered some of these early tunnels, snagging in their buckets bits of track, ore cart and other paraphernalia left behind.

Before a dredge could penetrate the permafrost, it first had to be thawed out. To do this, tracts of land designated for subsequent mining were equipped months beforehand with a matrix of pipes inserted deep in the earth and lined with perforations to allow steam to be pumped into them to soften the surrounding material.

When it came time to move, the entire apparatus was winched along on skids to its new location. The areas the dredge had worked previously were identifiable by rows of neatly piled rocks similar to  those I’d seen along the rivers back home—the detritus of industrial-scale mining operations.

Permafrost isn’t something people in California would have occasion to experience. Encountered chiefly in polar regions, permafrost is a thick sub-surface of soil that essentially never completely thaws out. The implications of this can be profound, affecting the surrounding vegetation in dramatic ways. The  frozen   ground limits the coexistence of trees except in places where hot springs have softened the soil.  

Permafrost also affects the placement of buildings: As the spring thaw softens the soil’s upper layers, undulations result that wreak havoc on their foundations. To counter this, the older houses in Nome were set to rest on large beams supported by piers set atop the ground. This allowed the houses to be adjusted back to level in the springtime through the use of hydraulic jacks.

By way of illustrating the folly of ignoring the physics of fluid dynamics, one overly-optimistic individual had erected a structure with a cement foundation on the east side of town a few years before my visit. Jutting perilously aslant and unusable, it stood as a silent yet graphic commentary on the do’s and don’ts of tundra settlement.  

Tim Konrad

(To be continued . . )