Post design-evaluations Sample Clauses

Post design-evaluations. Full-scale tests should be conducted at all sites on a periodic basis where possible. If a source of water is available (e.g. nearby fire hydrants or water trucks), these tests should be conducted using controlled and measured inflow rates that result in significant ponding in the facility. If water sources are not available, inflow rates should be monitored if at all possible. By monitoring inflow rates, relationships can be developed that give infiltration rates as a function of stage or water level in the facility. These types of relationships are particularly valuable if computer-simulations are used to evaluate the design performance, or if continuous hydrographs are used in the design approach. Appendix A describes methods for conducting and analyzing data from the full-scale tests with known inflow rates. In cases where the full-scale tests indicate infiltration rates that are significantly less than the design rates, the facility may need to be modified. If the lower rates are expected to be caused by soil plugging or bio-fouling, then remediation of the existing pond may be possible. For some sites, particularly those where the lower rates are due to unexpectedly high groundwater levels, there may be little that can be done, other than increasing the areal extent of the facility or designing an overflow system. The approaches described in this manual can be used to re-evaluate these facility retrofit options. In many instances, more refined and sophisticated analyses will be warranted.