CERCLA Investigation and Remediation Process
Understanding the CERCLA Site Investigation and Remediation Process at Longhorn Army Ammunition Plant
This flow chart demonstrates the step‐by‐step process that the Army is following to characterize and clean up contamination at the active Environmental Restoration Program sites at the Longhorn Army Ammunition Plant (LHAAP) in accordance with the Comprehensive Environmental Restoration, Compensation, and Liability Act (CERCLA) requirements. It also shows the step each site is at in the process, as of the March 12, 2026 Restoration Advisory Board (RAB) meeting. If you have any questions or concerns, the public is invited to every RAB meeting and you are welcome to come and get additional information. If you can’t make it to a meeting, you can also contact one of the RAB members to get your questions or concerns answered, or email the Army co‐chair, kelly.u.norwood.civ@army.mil. All of the LHAAP sites have completed Phase 1 – Investigation.
There are three sites at the Remedial Design (RD) step (LHAAP‐18/24, LHAAP‐29, and LHAAP‐47). This is the phase in the cleanup process where engineering plans, technical drawings and specifications are developed for the selected cleanup alternative.
Sites LHAAP‐001-R-01, LHAAP‐003-R-01, LHAAP‐04, LHAAP‐12, LHAAP‐16, LHAAP‐17, LHAAP‐35A (58), LHAAP‐35B (37), LHAAP‐46, LHAAP‐50, and LHAAP‐67 are at the Remedial Action (Operations) (RA(O)) step. During RA(O), the only activities being performed are long‐term groundwater monitoring, and operation and maintenance of the remedy. RA(O) will continue until the cleanup levels for Response Complete (RC) and Site Closeout (SC), as specified in the Record of Decision (ROD), are achieved and no further action is required.
Site LHAAP-3 is at Response Complete/Site Closeout (RS/SC), meaning the required cleanup levels have been achieved and the site has been closed with no further action required.
It is important to note that there is no particular timeframe associated with an individual step in the process or for an individual site to achieve RC and SC. The rate at which sites advance through the process is determined mainly by the complexity of the site, the nature of contaminants and contaminated media, and the final remedy specified in the ROD.
Activities undertaken by the Army at all LHAAP sites, regardless of which step in the CERCLA process they are at, are conducted in a manner that is protective of human health and the environment.
This chart will be updated yearly in advance of the RAB meetings to show progress achieved since the previous meeting. The updated charts will be posted on this website.