Filter Media for Nutrient Removal in Natural Systems and Built Environments: II—Design and Application Challenges

Both surface and groundwater systems can be contaminated by treated or untreated wastewater discharged from improper on-site wastewater treatment systems, nutrient-laden agricultural runoffs, landfill leachate disposal with high nutrient concentrations, and increasing use of fertilizer in residential communities. This elevated nutrient level in surface and groundwater systems burdens the operation and maintenance cost of water treatment plants when the contaminated source water is to be made available for drinking water use. Most of the nutrient removal techniques using sorption media are based on laboratory experiments and limited field applications. The objective of this article was to investigate the current design and application challenges of using sorption media for nutrient removal in this field based on the basic understanding gained through a critical and thorough review of all relevant laboratory work. Retention and detention pond techniques for stormwater treatment, permeable reactive barriers for groundwater treatment, and passive on-site wastewater treatment are among the few examples in this emerging area. It is notable that these field applications have demonstrated some success for nutrient removal. Even at its simplest, identifying the general design features specific to different applications is by no means an easy task, and critical comparison and evaluation of the potential use of sorption media is essential. In this article, relevant technologies with future research potential are systematically reviewed to illuminate the design and application challenges.