Comparison of a modified and traditional rapid infiltration basin for treatment of nutrients in wastewater effluent

A traditional rapid infiltration basin (RIB) has been compared to a modified RIB constructed with manufactured biosorption-activated media (BAM) to evaluate nitrate removal from wastewater effluent. The RIBs are used for reclaimed and excess stormwater disposal. In this work, a mixture of clay, tire crumb, and sand (CTS) was selected to serve as the BAM material (Bold and Gold™ CTS media). Each RIB was constructed with two feet of either sand or BAM, covering more than 43,600 square feet of surface area. Over an eight-month period, loadings to the BAM RIB and traditional RIB each approximated 5.4 million gallons (MG) per acre. Water samples collected from lysimeters installed below the 2 foot of sand or BAM materials were analyzed for nutrients. Results suggest that under the conditions of the study BAM removed approximately 31% more nitrate-nitrites and total phosphorus than the traditional RIB. Additionally, BAM removed approximately 18% more total nitrogen than the traditional. PRACTITIONER POINTS: Biosorption-activated media (BAM) removed nitrate-nitrites from reclaimed water more effectively than sand in rapid infiltration basins. BAM could serve as an alternative media for nutrient removal from water prior to release to the environment. Total nitrogen removal was most influenced by NO_x removal, with a few removals influenced by TKN. Nutrients could not be effectively removed using BAM or sand from reclaimed water at threshold concentrations below two parts per million.