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EPA requires water systems use EPA-approved laboratories for the analysis of the 25 contaminants. All laboratories conducting analyses for Unregulated Contaminant Monitoring Regulation 2 (UCMR 2) must be approved by EPA.

The Laboratory Approval Program is voluntary and applies only to laboratories intending to analyze UCMR 2 samples. Laboratories planning to conduct analyses must first successfully complete the registration and application process according to the specified schedule, and receive formal written approval from EPA. Laboratories are encouraged to apply for approvals as early as possible.

Step-by-Step Laboratory Approval Process

The laboratory approval process is designed to assess whether laboratories meet the required equipment, laboratory performance, and data reporting criteria described under UCMR 2. With the exception of EPA Method 525.2, the methods do not currently have an established certification program. Applicants already certified by their state, primacy entity, or accredited through the National Environmental Laboratory Accreditation Conference (NELAC) to conduct drinking water analyses using Method 525.2 must still perform the UCMR 2 approval steps, including the related Proficiency Testing (PT).

The steps for the laboratory approval process are:

Maintaining Laboratory Approval

Approved laboratories must adhere to the quality assurance/quality control (QA/QC) procedures and criteria outlined in the method(s) and rule language to maintain their approval status. Laboratories must also post occurrence data, and required QC data electronically via the Safe Drinking Water Accession and Review System (SDWARS) within 120 days of sample collection date. Failure to post data using SDWARS may result in EPA revoking the laboratory's approval status. Once a laboratory is disapproved, it cannot be re-approved during the UCMR 2 monitoring period. Laboratories applying for approval and laboratories conducting analyses may be subject to on-site laboratory audits.

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