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How Does the CLP Work?

The Contract Laboratory Program (CLP) operates through a network of program participants who manage all aspects of sample scheduling, tracking, analysis, data production, contract compliance, and payment. Each sample processed by the CLP is properly documented for timely, accurate, and complete analysis of requested parameters. The following processes ensure CLP customers will be provided with data of known and documented quality.

Sample Scheduling and Shipping

CLP analytical services begin when samples are scheduled for analysis. The CLP user requests the samples through the EPA Regional Sample Control Coordinator (RSCC). The RSCC contacts the Sample Management Office (SMO), a contractor-operated facility, on a weekly basis to initiate sample scheduling. When SMO receives the specific information regarding a site, it assigns a unique Case Number to track sample information.

Once samples are scheduled, SMO assigns a laboratory to perform the required sample analyses. SMO then contacts the RSCC and provides the laboratory assignment information for each case.

The samples are collected by Regional samplers once a laboratory is assigned. They contact SMO to report the number and matrices of the samples, as well as the requested analyses. The samples are shipped to the assigned laboratory after the sample collection process is complete. Samples are delivered in a Sample Delivery Group (SDG). An SDG is a group of 20 or fewer field samples within a Case, received over a period of up to 3 to 7 calendar days, depending on the contract.

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Laboratory Analysis

When the samples arrive at the assigned laboratory, the sample custodian verifies the receipt and condition of the samples and documents it on the CLP Traffic Report/Chain-of-Custody (TR/COC) form. The laboratory contacts SMO for resolution if there are any issues regarding the samples. SMO documents all communication with the laboratory. Unless otherwise directed by EPA, the laboratory proceeds with the sample analyses according to the appropriate CLP Statement of Work (SOW). Laboratories are required to return the SDG Cover Sheets and TR/COCs within three working days from the receipt of the last sample in the SDG. Data from all samples in an SDG are due concurrently to SMO and EPA.

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Analytical Data Inspection

The data must be reviewed by SMO and the EPA Region from where the samples were collected after the laboratory performs the required analyses. The Regions review analytical data using the National Functional Guidelines for Data Review to determine whether additional action is necessary. Individual Regions may supplement the data review process with additional review and validation based on Region-specific or site-specific concerns.

Laboratories are required to submit their data electronically and in hardcopy to SMO. SMO evaluates both electronic and hardcopy data to verify that the analyses have been performed in accordance with the requirements in the SOW. The review results are then delivered to Regional customers via the Internet.

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Invoice Processing

The CLP invoice and payment process provides financial information useful in potential enforcement actions. CLP laboratories submit invoices for payment of the analytical services that they performed to SMO and EPA’s Financial Management Center (FMC) for processing.

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