Consistent with Ontario municipal discharge requirements, independent quality assurance (QA) testing has demonstrated that SPI units are effective at reducing total suspended solid (TSS) concentrations within storm sewer effluent by greater than 80% in instances where the initial TSS concentration is greater than 100 mg/L.
SPI removal efficiency is calculated based on the difference in TSS concentrations measured at the inlet of Chamber #1 and outlet of Chamber #2. Where representative effluent samples can be collected down-gradient of the SPI (i.e. outfall), additional samples are collected and analyzed to determine the final removal efficiency.
TSS analyses of all water samples has been conducted by CALA accredited laboratories.
In addition to evaluating TSS removal efficiency, Storm Pal has conducted field studies to determine the particle size distribution of sediments retained by the SPI.
To conduct the analysis, multiple sediment samples were collected from various locations within Chamber #1 of the SPI. The individual samples were then mixed together to produce a representative composite sample and a sieve analysis was conducted to remove all particles greater than 75 microns in size.
The portion of the composite sample passing the 75 micron sieve (i.e. 57% by weight comprised of fine sediments and clay) was then analyzed by computer digital imaging to determine the distribution of finer particles.
Based on the analytical results, the SPI has proven effective at retaining particles less than 5 microns in size as indicated by the distribution curve.
For more information regarding the quality assurance testing, see the particle size distribution results below or contact us directly.
For detailed information pertaining to the distribution of finer sediments retained by SPI, please refer to the link below.