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Chemical Data Reporting

Data Quality Assurance

EPA conducts a number of activities every reporting cycle to ensure the quality of Chemical Data Reporting (CDR) data reported to EPA, including:

Providing reporting guidance and technical assistance to submitters

  • Each reporting cycle, EPA publishes detailed guidance documents for submitters and other interested parties via the CDR website. These documents provide detailed instructions to help submitters determine and complete their reporting obligations under CDR.
  • EPA also provides support to companies through a range of resources, including the TSCA Hotline, CDX help desk, and the e-CDRweb mailbox. Resource materials are available at How to report to CDR for 2020.
  • E-CDRweb is a web-based, interactive, user-friendly tool that guides users through the CDR reporting process. The tool contains intelligence to prevent submitters from making common data entry errors and alerts users to possible errors so that they can double check their forms before submitting them.
  • CDR data is transparent and accessible to the public, except for information that is claimed as confidential business information.

Data quality checks used to verify the validity of CDR submissions

  • The CDR Program requires each Form U submitted to EPA be signed by an authorized official (e.g., senior manager/owner/operator) of the reporting site.
  • Each Form U submitted using e-CDRweb is immediately loaded into the CDR staging database tables for analysis. The data is queried and examined for any data outliers or data sets that do not comply with the reporting requirements. If any data outliers or unexpected data sets are identified, additional queries are run to verify the data and the submitted forms are compared against the query results to verify accuracy.
  • EPA then performs a technical audit and data quality checks of selected submissions. If potential errors are identified in the forms submitted, EPA sends a Data Quality Alert (DQA) or a Notice of Significant Error (NOSE) to the submitter. These notices indicate what the potential errors are and request that the submitter provide EPA with corrections, if necessary. EPA also makes follow-up telephone calls, as necessary. If a potential error could materially affect the validity of EPA's release of the data, then EPA may contact the submitter for clarification.
  • EPA performs additional data quality checks as it prepares the data for public release.
  • Finally, EPA conducts further analyses when inconsistencies in the CDR data are identified and updates the database as necessary.

Data validation and analysis after the deadline

Forms submitted after the reporting deadline are immediately loaded into the CDR data processing system for analysis and combined with data from previously submitted Forms. Similar to the process for other submissions (e.g., amendments to original Form U), the data are queried and examined for any data outliers and checked for accuracy. EPA performs periodic extractions of the data and posts updated versions of the database to the CDR website.

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