Abstract:
There are a number of different types of filter media which are used for stormwater treatment. Compost
is potential media that can be used to filter stormwater runoff by removing heavy metals, oil, grease,
pesticides, sediment, and fertilizers from storm water runoff. The leaching of dissolved organic carbon
(DOC) and nutrients from a compost-based filtration media can have a significant impact on the design
and the performance of the treatment system.
A filtration media tested for this study was comprised primarily of compost, ash and sand. The media
used in the column experiment has a permeability of 3.6* 10-2 cm/s, a porosity of 31% and a uniformity
coefficient of 2.38. The column leaching experiments show an initially high DOC concentration of 264
mg/L drops to below 10 mg/L after 75 pore volumes (PV). The DOC concentration sharply increases to
19 mg/L from the background of 4 mg/L when the flow was turned off. The effluent EC and Colour
have same trendlines as the effluent DOC. The data suggest that the leaching DOC can be significant
over relatively short time periods when compost-based filtration media is used under continuous flow
systems.
