Trinidad Rancheria - Trinidad Pier Reconstruction Project - Sediment and Water Sampling, Characterization, Reporting and Consulting Services
Partially funded by a grant from the State Water Resources Control Board (SWRCB) to reduce pollution to the Trinidad Head Area of Biological Significance (ASBS), the Trinidad Pier Reconstruction Project will replace the existing wooden pier (owned by the Trinidad Rancheria) with non-toxic cast-in-steel-shell concrete piles and pre-cast concrete decking. Indirectly, the project will improve water quality conditions and provide additional habitat for the biological community in the ASBS. ADH was contracted by Trinity Valley Consulting Engineers (TVCE) to implement monitoring and assessment requirements of the SWRCB Grant Agreement No. 10-409-550, including preparation of a Project Assessment and Evaluation Plan (PAEP), Quality Assurance Project Plan (QAPP), and preparation and execution of a Monitoring Plan (Sampling and Analysis Plan). Monitoring tasks include pre-construction seawater and subtidal sediment sampling and post-construction seawater, stormwater and subtidal sediment sampling.
Based upon the Trinidad Pier Reconstruction Project Water Quality Monitoring Plan (MP), ADH developed and performed all technical aspects of the monitoring project including installation of stormwater flow monitoring and sampling equipment and contracting with a National Environmental Laboratory Accredited Program (NELAP) certified analytical laboratory for sample analysis. In accordance with the PAEP, QAPP and MP, ADH staff performed all pre-construction seawater and sediment grab sampling from a single composite area around the pier within Trinidad Harbor. Post-construction sediment sampling and flow-weighted stormwater sampling for three storm events will be performed following construction completion.
All water and sediment samples collected were subjected to analytical testing for a comprehensive suite of physical and chemical analyses as specified by the QAPP and MP. Analytical results were evaluated to determine pre- and post-construction water and sediment quality characteristics. Results were evaluated in relation to applicable state and federal criteria and guidelines, including the California Ocean Plan and National Oceanographic and Atmospheric Administration (NOAA) Sediment Quality Guidelines. An interim pre-construction sampling and analysis report has been prepared by ADH for TVCE and a final report on all pre- and post-construction monitoring, including stormwater quality, flow monitoring and pollutant loading will be prepared upon project completion.