Journal of Cold Regions Engineering

“Biogenic interference” is that portion of natural organic matter in soil that cannot be distinguished from petroleum in a standard test for contamination. Biogenic interference is normally a small fraction of total natural organic matter. In organic soils, however, biogenic interference alone can exceed “petroleum” limits set by regulatory agencies. A test using a pyrolysis-gas chromatograph/flame ionization detector (GC/FID) was developed to quantify biogenic interference in soil samples from northern Alaska. The samples had no known history of contamination, so all measured “petroleum” was derived from biogenic interference. The pyrolysis test was found to predict biogenic interference in soil samples more accurately than any combination of standard soil tests, including C:N ratio, pH, percent organic carbon, extractable carbon, humic acids, fulvic acids, low molecular weight acids, hydrophobic neutrals, and hydrophilic neutrals. Analysis of samples contaminated in the laboratory confirmed that the pyrolysis test could quantify biogenic interference in soils recently contaminated by petroleum.

Rural Alaskan communities have special challenges to supply dependable heat and electric power while preserving environmental quality. To help address these issues in a coherent fashion, we have established an energy center at the University of Alaska Fairbanks. Initially, we will evaluate fuel cells and reformers in a test chamber, looking at both performance and reliability. Later, we will study the integration of the electric and other utilities and focus on arctic engineering issues. In designing the test chamber, we were confronted with a number of conflicting heat balance issues related to (1) additional heat for freeze protection and (2) removal of heat generated by people and equipment. This paper discusses some of the details of how we addressed these issues.

This paper presents a numerical model that simulates the dynamic failure and re-formation of an ice jam. The model comprises a simultaneous solution of the 1D, unsteady flow equations (conservation of mass and momentum) for water flow and ice motion. Its use is demonstrated in the routing of flow hydrographs through a channel containing an initial jam or accumulation of broken ice. The model shows the extent to which changes in flow discharge may affect profiles of jam thickness and flow depth for these situations. It also shows how ice momentum may affect the jam-thickness profile. Dimensionless parameters, characterizing initial jam stability and the shape of the hydrograph, are identified to indicate conditions when changes in flow discharge and ice momentum should be taken into account when estimating jam thickness.

This note presents an experimental study on the fracture toughness of frozen soil. Notched bend specimens were used in the test. Some preliminary results are given to describe the effects of temperature, water content, and loading rate on the fracture toughness of frozen soil.