EFFECTS OF ALTERNATIVE ROAD SALTS ON SOIL LEACHATE QUALITY
Open Access
- Author:
- Jain, Karan Rishabhkumar
- Graduate Program:
- Environmental Pollution Control
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- March 26, 2018
- Committee Members:
- Shirley Elizabeth Clark, Thesis Advisor/Co-Advisor
- Keywords:
- Deicing salts
Road Salts
Alternative road salts
road salt and soil
deicing salt and soil
deicing salt and groundwater - Abstract:
- In winter, stormwater runoff contains a high amount of salts mainly due to the application of deicing salts such as sodium chloride (NaCl) to melt snow and ice by lowering its freezing point. A mesocosm-scale experiment was conducted over a period of 4 months using (12 artificial stormwater [ASW] runoff events + 7 artificial snowmelt [ASM] runoff events). This research experiment compared the impact of three alternative road salts to the traditional sodium chloride in terms of the flow rate of water through the soils, plus the retention of copper in soil. The salts used in this research were chloride and acetate salts of sodium and calcium. Acetate-based salts were selected to mimic the behavior of organic-based deicers such as desugared beet juice. Turbidity, conductivity, and pollutants such as chemical oxygen demand (COD) and copper were analyzed in the leachate. The results concluded that the application of chloride-based salts reduced the infiltration rate whereas acetate-based salts had minimal impact indicating that the flow rates were influenced by anion. For calcium-based salts especially calcium chloride, there was less retention of influent copper when compared to the sodium-based salts. Application of acetate-based salts increased organic removal (measured as chemical oxygen demand [COD]) which may indicate the growth of the microbial community in the soil. To confirm the water results, at the end of experiment, the soil was tested for parameters affecting soil fertility (calcium, magnesium, potassium, pH, phosphorus), total nitrogen (TN), total carbon (TC), extractable sodium and metals such as copper and zinc. The soils’ results confirmed that less copper in the simulated runoff was retained on the soil after salt application than was retained during “ASW events” where salt was not included in the runoff.