No abstract

Non-hazardous waste disposal and diversion trends in Ontario from 1996 to 2010 were identified using parametric and non-parametric statistical methods, and the temporal variability of its waste diversion practices were examined. Ontario’s diversion was sensitive to waste diversion policy and residential diversion programs. Total waste diversion increased by 85% in 14 years. Results suggested that waste minimization may be more effective than recycling on Ontario diversion rates. Programs targeting non-residential sectors are recommended, specifically for smaller businesses with limited waste management budgets. Linear regression and Mann-Kendall tests detected significant increasing trends for residential waste diversion. In contrast, non-residential diversion had a decreasing trend using linear regression. A significant upward trend (S = +10) was found for Ontario’s total waste diversion using Mann-Kendall tests. Highly significant upward trends were observed for plastic and organic recycling. Mann-Kendall tests were found more appropriate for waste trend analysis in the present study.

In this paper, waste management in Alberta (AB) and British Columbia (BC) from 1996 to 2010 are examined with respect to generation characteristics and management efficiency. The daily average waste generation rates in AB and BC were 3.34 kg/capita and 2.50 kg/capita, respectively. It was found that annual family income has a positive relation with residential waste generation in both provinces, as did the proportion of educated citizens. Gross domestic product was positively related to non-residential waste generation in AB, and negatively related in BC. Annual agricultural farm cash receipts were positively related to non-residential waste generation in both provinces, and AB’s industry earnings were significantly higher. Between 1998 and 2010, the average diversion rate in AB was 15.1%, and BC’s was 32.9%, which place them on opposing sides of the national average (23.4%). Total operating expenditures were similar in both provinces, yet BC’s waste diversion was more than double AB’s.

High Canadian waste disposal rates necessitate landfill gas monitoring and accurate forecasting. CO estimates in LandGEM version 3.02 currently rest on the assumptions that CO is a function of CH, where the two gases make up nearly 100% of landfill gas content, leading to overestimated CO collection estimates. A total of 25 cases (five formulas, five approaches) compared annual CO collection at four western Canadian landfills. Despite common use in literature, the 1:1 ratio of CH to CO was not recommended to forecast landfill gas collection in cold climates. The existing modelling approach significantly overestimated CO production in three of four sites, resulting in the highest residual sum of squares. Optimization resulted in the most accurate results for all formulas and approaches, which had the greatest reduction in residual sums of squares (RSS) over the default approach (60.1 to 97.7%). The 1.4 Ratio approach for L :L yielded the second most accurate results for CO flow (mean RSS reduction of 50.2% for all sites and subsection models). The annual k-modified LandGEM calculated k's via two empirical formulas (based on precipitation) and yielded the lowest accuracy in 12 of 20 approaches. Unlike other studies, strong relationships between optimized annual k's and precipitation were not observed.

Temporal and spatial variations in landfill gas generations and emissions have been observed and reported by others. Real-time gas data between 2008 and 2014 from a municipal landfill located in a cold, semi-arid climate were consolidated to fit a linear-interpolated form of LandGEM. Seasonal variations in gas collection were observed in the landfill. LandGEM's default decay rate k was not applicable for this Canadian landfill due to significant overestimation (32.2% error). Optimal seasonal k and L collection parameters had 8.1% error compared to field data, compared to 8.3% error using optimal annual parameters. The optimal k was 0.0118 year and the k was 0.0141 year (14.7% difference), with a corresponding L of 100.0 m/Mg which changed negligibly between the sets. Three pseudo-second order iterative methods were considered, and evaluated using RSS and generation parameters in the literature. A simple application study was conducted using LFGcost-Web, and found the increased precision of seasonal k's resulted in negligible differences with annual optimized k. The default parameters overestimated the net present worth by 12-155% for three of the four common LFG energy projects.