# Council Directive 1999/31/EC of 26 April 1999 on the landfill of waste, Division 3: Emission data: water, leachate and gas control

Extent: E+W+S+N.I.

Sampling of leachate and surface water if present must be collected at representative points. Sampling and measuring (volume and composition) of leachate must be performed separately at each point at which leachate is discharged from the site. Reference: general guidelines on sampling technology, ISO 5667-2 (1991).
Monitoring of surface water is present shall be carried out at not less than two points, one upstream from the landfill and one downstream.
Gas monitoring must be representative for each section of the landfill. The frequency of sampling and analysis is listed in the following table. For leachate and water, a sample, representative of the average composition, shall be taken for monitoring.
The frequency of sampling could be adapted on the basis of the morphology of the landfill waste (in tumulus, buried, etc). This has to be specified in the permit.
The frequency of sampling could be adapted on the basis of the morphology of the landfill waste (in tumulus, buried, etc.). This has to be specified in the permit.
The parameters to be measured and the substances to be analysed vary according to the composition of the waste deposited; they must be laid down in the permit document and reflect the leaching characteristics of the wastes.
If the evaluation of data indicates that longer intervals are equally effective, they may be adapted. For leachates, conductivity must always be measured at least once a year.
Thease measurements are related mainly to the content of organic material in the waste.
CH4, CO2, O2, regularly, other gases as required, according to the composition of the waste deposited, with a view to reflecting its leaching properties.
Efficiency of the gas extraction system must be checked regularly.
On the basis of the characteristics of the landfill site, the competent authority may determine that these measurements are not required, and will report accordingly in the way laid down in Article 15 of the Directive.
2.1 and 2.2 apply only where leachate collection takes place (see Annex I(2)).
Operating phase
After-care phase
2.1. Leachate volume
monthly
every six months
2.2. Leachate composition
quarterly
every six months
2.3. Volume and composition of surface water
quarterly
every six months
2.4. Potential gas emissions and atmospheric pressure(CH4, CO2, O2, H2S, H2 etc.)
monthly
every six months

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Source: https://www.legislation.gov.uk/eudr/1999/31/annex/III/division/3 (the official version)
Page: https://openlegislation.uk/eu-directive-1999-31/annex-III/division-3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.