# Messer LLC - Cinnaminson Groundwater Contamination
> **Administrative - Formal** · FY2025 · — · Unilateral Administrative Order Without Adjudication
## Case
- **Activity ID:** `3604563527`
- **Case Number:** 02-2025-2021
- **Type:** Administrative - Formal
- **Lead:** EPA
- **Outcome:** Unilateral Administrative Order Without Adjudication
- **Penalty assessed:** —
- **Cost recovery:** —
- **Compliance action $:** —
- **Multimedia (multi-env):** —
## Defendants
- Messer LLC (settlement)
## Summary

This is a Unilateral Administrative Order (UAO) issued to Respondent for the vapor intrusion portion of the remedial action for Operable Unit 3 of the Cinnaminson Groundwater Contamination Site. Under the UAO, Respondent with install vapor intrusion mitigation systems as required and perform operations, maintenance, and monitoring of existing and future vapor intrusion mitigation systems.

UAO modification signed on November 19, 2025.

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*Source: [EPA ECHO](https://echo.epa.gov/) · AI Analytics · CC0 1.0*