Leaaf has conducted semi-annual groundwater assessment monitoring at the Recovery 1 Landfill since 2016. The Recovery 1 Landfill is a closed municipal landfill in its 30-year post closure period. Groundwater samples were collected from the nine perimeter monitoring wells in February and June 2019. The assessment monitoring program required the sampling and analysis for the parameters listed in Table 2 of Louisiana Administrative Code (LAC) 33:VII.3005.Appendix C during the first semi-annual monitoring. The parameters listed in Table 1 of LAC 33:VII.3005.Appendix C and any parameters detected during the first semi-annual monitoring events were sampled in the second semi-annual sampling event. Quality Assurance/Quality Control (QA/QC) samples were collected during each monitoring event per the Louisiana Department of Environmental Quality (LDEQ) Risk Evaluation/Corrective Action Program (RECAP). Prior to the collection of groundwater samples, each well was gauged to determine groundwater flow direction and for potentiometric surface map development. Groundwater samples were collected after purging each well with a micropurge flow-through cell that collects real time groundwater monitoring characteristics (pH, temperature, turbidity, conductivity, and oxidation-reduction potential). Samples were collected once groundwater monitoring characteristics were stable to ensure that the samples collected were representative of the groundwater zone. Purge water was containerized onsite.
At the time of sampling, maintenance was required on the monitoring wells, including removal of vegetation in the vicinity of the well pads and replacing well locks. Monitoring well integrity was inspected during each event to determine if more extensive repairs on the wells were needed. Following the receipt of the laboratory results, a semi-annual monitoring report was prepared for each event. The semi-annual monitoring event reports included: a summary of the groundwater event; description of groundwater characteristics and potentiometric flow; summary of analytical results; data quality evaluation; development of Groundwater Protection Standards (GWPS), per RECAP; comparison of analytical results to RECAP Groundwater Screening Standards and GWPS; trend analyses of current and historically detected parameters; potentiometric surface map; and isopleth maps for detected parameters. Leaaf coordinated the disposal of investigative derived waste (monitoring well purge water) following the monitoring events. The semi-annual monitoring event reports were submitted to the LDEQ Waste Permit Division following approval from the City of New Orleans Department of Sanitation.