Abstract:
Compost is used in bio-retention systems to mend soil quality, water permeation, and retention of contaminants. However, compost contains dissolved organic matter, nitrate, and phosphorus, all of which can leach out and potentially contaminate ground and surface waters. To lessen the leaching of nutrients and dissolved organic matter from compost, granular activated carbon (GAC) and sand may be mixed into the bio-retention systems. Objective of this study was to test whether granular activated carbon (GAC) and sand mixed into water washed vermi-compost can reduce the leaching of organic carbon, nitrogen, and phosphorus.
This study was divided into two phases. Phase-1 was control run in which pure media was used in the columns. Phase-2 was the main run in which two media combinations were used, compost + sand and compost + granular activated carbon. Both phases were run continuously for 24 hours and samples were collected after every 2 hours. Afterwards, samples were analyzed for different parameters, which include pH, electrical conductivity (EC), total dissolved solids (TDS), ortho-phosphates (OP), nitrates, organics and total organic carbon (TOC).
