Whittier Narrows Operable Unit | Tetra Tech R&D

Data Management Services for Whittier Narrows Operable Unit — California Department of Toxic Substance Control

Whittier Narrows Operable Unit (WNOU) is part of the San Gabriel Valley (Area 1) Superfund Site, a 11-square-mile area of contaminated groundwater in Los Angeles, California. Monitoring of the WNOU includes over 125 monitoring wells, 7 extraction wells, and other locations associated with the treatment plant. Tetra Tech has been successfully performing services for DTSC at the WNOU since 2016, including:

  • Migration of historical site data from various sources into existing DTSC EQuIS database. Effort included resolving some complex issues such as multiple IDs for a single well, identification of duplicate data, and blending reference data with data in existing database.

  • Performing quarterly imports of data from EPA databases and the State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment Program (GAMA) database.

  • Design and set up of a secure Share Point site to manage the entire data flow, including upload of data, download of electronic data deliverable (EDD) templates and access to reporting capabilities.

  • Hosting the system within Tetra Tech’s Azure cloud and managing security for users using multiple levels of user access.

  • Created numerous web-based reports, that can be scheduled to be generated at specific times and emailed to users.

  • Customization of previously developed Chain of Custody software to handle site-specific needs. Software allows users to enter chain of custody data in the field and upload to the database.

  • Customization of previously developed desktop software for data access, which uses a series of wizards to view and graph data such as chemistry, well flows, water levels, well construction and lithology data.

  • For all sampling events, perform completeness checking using previously developed software to compare chain of custody data to data in the database to find any missing data.

  • Creation of a web mapping system to allow users to access and view a subset of the data contained within the large WNOU database.

  • Hosting of periodic training sessions for use of the data management system and software to teach new users and update existing users on new features and capabilities.


Christine Lew


(925) 280-7426