Storm Water Technical Support for a Proposed Solar Facility

For a proposed 7,000-acre solar power plant using solar parabolic trough technology in southern California, Geosyntec has provided on-going construction-phase storm water technical support.  Geosyntec was initially contracted to perform a technical review of the Drainage, Erosion, and Sediment Control Plan (DESCP), a stipulated project approval requirement of the California Energy Commission (CEC).  Following acceptance of the DESCP by the CEC, Geosyntec was contracted to prepare the Storm Water Pollution Prevention Plan (SWPPP) for this 1,000MW concentrated solar thermal electric generating facility.

Geosyntec provided the following services:

  • Technical review of DESCP for completeness and consistency with both the CEC requirements and the California NPDES Construction General Permit.
  • Site specific construction storm water risk analysis in accordance with the California Construction General Permit (CGP – Order No. 2009-009-DWQ). Risk analysis includes using RUSLE equation to estimate soil loss over the length of the project, using site specific criteria to optimize risk determination and a review of 303 (d) listed water bodies.
  • SWPPP developed to conform to new regulations under the California Construction General Permit (CGP) and integrate and optimize CEC requirements / mitigation measures from other environmental disciplines (e.g. habitat mitigation requirements and air quality requirements). New CGP regulations include: minimum Best Management Practice (BMP) requirements, storm water sampling, and adherence to Numerical Action Levels for pH and Turbidity.

The facility is being constructed using design build methodology and Geosyntec has worked with the contractor and owner to develop SWPPP phasing to optimize implementation, achieve regulatory compliance and present cost-effective, buildable solutions.