Monitoring data for all wells is given in a zipfile with separate csv files per well named by unique SITE_CODE parameter (SITE_CODE.csv), and one long-format table with all wells combined (all_gwl_data.csv).
No crosswalk between SITE_CODE or SWN and WCRNumber exists to link these data to OSWCR, so finding well completion reports for monitoring wells identified in this dataset requires reaching out to the primary monitoring agency.
Data comes from the roughly 1.8 million records in the Periodic Groundwater Level Measurements database, which is regularly maintained and supersedes CASGEM.