In 1988 a joint research program was developed and implemented by the Alberta Research Council and ESSO Resources Canada Limited to identify the impact of different loading rates of KCl, NaCl, and freshwater gel drilling wastes landspread on Luvisolic soils occurring in the Cold Lake area.
During 1992 four site visits were made to complete various tasks. The plots were harvested on June 22 and 23 and, again, on August 17 and 18 at which time soil sampling was also completed. Plant tissue was collected for analytical purposes on June 22.
In 1992 the highest mean pH value recorded was 7.5 for treatment FW5 which represents the upper limit of the good rating when considering soil quality associated with a forage crop end land use. The CaCO3 equivalent values indicated that none of the treatments would be limiting to plant growth as a result of CaCO3 levels.
The saturated paste extract data illustrated the changes that occurred in the soils as a result of waste application and the changes that occurred between the 1988, 1989, 1990, 1991, and 1992 sampling events. The mean EC values for all plots and all depths prior to waste application were well below 1.0 dS/m suggesting that there was no limitation to plant growth on the basis of EC (Alberta Soils Advisory Committee 1977). Data from the 1992 sampling program indicated that no limitations to plant growth should occur in the 0 to 15 cm depth interval for any of the treatments as a result of EC level.
The mean SAR values for all plots and all depths, prior to waste application, were below 1.0, suggesting that on the basis of SAR levels, the soils presented no limitation to plant growth. The 1992 data indicated that there were no limitations to plant growth on the basis of SAR for all treatments, except a slight limitation associated with the NaCl 10 treatment.
The effect of the addition of drilling wastes on the elemental enrichment of the brome grass was demonstrated by the enrichment ratio (ER). The tissue from the treated plots exhibited slightly elevated levels of sodium and chloride for all waste types. Tissue copper and zinc levels were improved (increased) by the addition of the drilling waste materials. The application of the different wastes at various rates had both positive and negative impacts on the soils and the plants grown thereon. Some conclusions with respect to waste application rates that can be applied were drawn. Determining maximum tolerable loading rates was difficult to do in the absence of guidelines as to how "tolerable" is defined. It was also concluded that liming potential as well as chloride addition should be used for assessing application rates for freshwater gel wastes.