In all results from the SimaPro 8 model, CMA Deicer was the least impactful to the environment whereas NaCl Deicer was the most impactful to the environment. The single score, represented in Ecopoints (MPt), was calculated first and broken down in to impacts to human health, ecosystems, and resources. As displayed in Figure 7, NaCl Deicer had the highest total Ecopoints
score, followed by CaCl2 Deicer, then OBPE Deicer, and CMA Deicer had the fewest total
Ecopoints. The total Ecopoint scores received for each deicer are found in Table 14. NaCl Deicer also scored the highest in the categories of human health, ecosystems, and resources and CMA Deicer also had the fewest Ecopoints in all three categories. To better understand the relative impacts of all deicers in terms of Ecopoints, Table 15 shows the relative magnitude of impact of each deicer as compared to CMA Deicer. Table 15 indicates that NaCl Deicer has a score 11.45
times greater than CMA Deicer. CaCl2 Deicer has a score 11 times greater than CMA Deicer.
Figure 8 displays the relative percentage of impact in terms of Ecopoints for each Deicer. This information coincides with the single scores of Ecopoints associated with each deicer and serves to visually demonstrate relative impact in terms of Ecopoints and categorized by impacts to human health, ecosystems, and resources. Table 16 provides the specific data per category from which the Ecopoints were derived. Ecopoints were calculated within SimaPro 8 and are intended to be a single metric of aggregated impact information that allows for easy comparison. Table 16 displays some of the information from which the Ecopoints were determined. Human health is reported in DALYs, impact to ecosystems is reported in species-years, and impact to resources is reported in USD. DALY (Disability-Adjusted Life Year) is a measure that equates to one lost year of healthy life. This is calculated by summing the average years of life lost as a result of premature death with the years of life lost due to health conditions. Species-year is a measure of the extinction rate of species by determining the extinction rate of a set number of species over a set number of years (World Health Organization, 2016).
Table 17 indicates the relative impacts of each deicer, per category, as based upon the original units. Each deicers magnitude of impact relative to CMA Deicer (the least impactful deicer) is displayed. In the categories of human health and ecosystems, impacts relative to CMA Deicer range from 12-18 times more impactful. In the category of resources, the difference is less profound, ranging from 4-6 times more impactful than CMA Deicer.
In all results from the SimaPro 8 model, transportation and application of the deicers were the least impactful to the process. As displayed in Appendix C, total transportation accounts for
approximately 0.52% of the NaCl Deicer process, 0.54% of the CaCl2 Deicer process, and 0.60%
of the OBPE Deicer process. The exception is that transportation accounts for approximately 24.22% of the CMA Deicer process. From this information, it is assumed that the production and mining processes are the largest contributors to a deicer’s pre-application environmental effects. This is discussed more in Section 7.
Figure 7: Total Ecopoints for Each Deicer
Table 14: Total Ecopoint Scores Received
Figure 8: Relative Percentage of Impact
Table 16: Individual Ecopoint Category Data
The impacts specifically in terms of Climate Change and Ozone Depletion are displayed in Figures 9 and 10. In Figure 9 all deicers are characterized and normalized to best display relative impacts to climate change. NaCl Deicer has the greatest impact to climate change and therefore represents 100% of the total impact and all other deicer impacts are displayed relative to NaCl
Deicer. CalCl2 Deicer will have 96.1% of the impacts from NaCl Deicer to climate change.
OBPE Deicer will have 81.5% of the impacts from NaCl Deicer to climate change. And CMA Deicer will have 10% of the impacts from NaCl Deicer to climate change.
In Figure 10 all deicers are characterized and normalized to best display relative impacts to ozone depletion. Again, NaCl Deicer has the greatest impact and therefore represents 100% of
the total impact and all other deicer impacts are displayed relative to NaCl Deicer. CaCl2 Deicer
will have 96.1% of the impacts from NaCl Deicer to ozone depletion. OBPE Deicer will have 81.5% of the impacts from NaCl Deicer to ozone depletion. And CMA Deicer will have 13.6% of the impacts from NaCl Deicer to ozone depletion.
Figure 10: Normalized Results of Ozone Depletion Contributions from SimaPro 8
Tables 18 and 19 display the impacts to climate change and ozone depletion for each deicer based upon the quantity of units released. Figures 9 and 10 are derived from the data in Table 18. Table 19 uses the raw data from Table 18 to also display the impacts of each deicer to climate change and ozone depletion relative to the deicer of least impact (CMA Deicer). This data coincides with information displayed in Figures 9 and 10 but serves to provide another metric with which to compare all deicers during the post-application model analysis.
Table 19: Relative Impacts of Climate Change and Ozone Depletion