Guidance

Contaminated land exposure assessment (CLEA) tool

Handbook and software to help assess the risks of contaminated land exposure for human health.

Documents

CLEA Software (Version 1.05) Handbook

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CLEA Software Version 1.071

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Details

You can use the CLEA software to:

  • derive generic soil assessment criteria using generic assumptions about the characteristics of contaminants and people likely to be present on site
  • derive site-specific soil assessment criteria by entering your own data on the characteristics of contaminants and people likely to be present on site or using a non-generic approach
  • assess whether a measured concentration in soil (and where available, measured site concentrations for contaminants within soil air, ambient and indoor air, and fruits and vegetables) would present a potential risk to human health for a particular set of circumstances

The handbook explains how you can do all of these things. Although it refers to version 1.05, the handbook is still valid for later software versions.

An update (1.071) to the software was published on 04/09/2015. The update includes the library data sets from the Defra research project SP1010 (Development of Category 4 Screening Levels for assessment of land affected by contamination). It also fixes a problem in version 1.07 with the adding of new chemicals. The revised software (version 1.071) has been published under the Government Open Licence and you should refer to this agreement for terms of use. While the software has undergone some additional testing, please report any further errors to the Environment Agency.

Published 27 May 2014
Last updated 7 September 2015 + show all updates
  1. The Contaminated land exposure assessment (CLEA) tool has been re-uploaded and is available to use.

  2. The Environment Agency has been alerted to a problem with the recent version of the CLEA tool. We are working to correct this and a revised version will be published as soon as possible. Until this time the CLEA tool has been removed.

  3. The CLEA software licence agreement (LIT 10168) is no longer valid. CLEA software version 1.07 is published under the Open Government Licence.

  4. CLEA Software update. Version 1.07 incorporates the approach and library data sets to support the outcome of the Defra Category 4 Screening Levels research project and is now Open Government Licence.

  5. First published.