The project is divided up into four drainage areas. At the outlet of each area, a new Stormceptor Water Quality structure will be added. The Stormceptor structures have been designed and analyzed by the Manufacturer based on the total area the structure receives from the respective drainage area along with the percent imperviousness within that area. The manufacturer can then determine the amount of total suspended solids (TSS) that are removed for each structure. The Stormceptor structures, manufactured by Rinker material, have previously been approved by LEED as a sufficient means of meeting Credit 6.2. However, the past approvals have been based on particle size distribution groups (PSD) that differ from the one proposed here. Our project will be designed using a PSD group (OK-110) approved and used in the local community and is as follows: Particle Size (
The applicant is requesting confirmation of whether the particle size distribution (PSD) group used in testing the removal efficiency of the proposed equipment is appropriate. Structural controls, including Stormceptor Water Quality structures, can be an acceptable means of achieving this credit. Based on the data provided, the use of this PSD group is considered acceptable because it appears to conform to accepted protocol for BMP monitoring.