Soil

Soil Testing and Soil Contamination

Soil can become contaminated in many ways. A common cause is leakage from an underground oil storage tank. The use of contaminated fill material, especially in older residential areas, has also led to soil contamination. In addition, industrial and commercial activities such as blacksmith shops, chemical laundries, and paint factories may have contributed to soil contamination.

Soil testing determines whether soil contamination is present and to what extent. In cases of severe soil contamination, remediation may be necessary. You may encounter soil contamination in various ways: when buying or selling real estate, applying for an environmental permit, or when reusing or disposing of soil. If you (as a private individual) come across an old underground oil tank that has been decommissioned but has not yet been remediated, you must report this tothe West-Holland Environmental Agency (ODWH) at.

Soil testing for lead has been completed  

During the 2019–2022 period, the province of South Holland commissioned soil surveys to test for the presence of lead at playgrounds and community garden complexes. The results of these surveys, as well as tips and information about lead, can be found here: Be Aware of Lead - West-Holland Environmental Service (odwh.nl)

Do you have any questions about the soil survey for lead? Please feel free to call the West-Holland Environmental Agency at071 - 40 83 100.

Soil Information

All soil data for the municipality has been entered into a digital soil information system. The municipality therefore has information on the soil quality or the presence of an underground tank at many locations. You can contactthe West-Holland Environmental Agency (ODWH)at to inquire whether soil information (including underground oil tanks) is available for a specific parcel. 

Earthmoving

It is not simply permitted to excavate sand, soil, or dredged material from one location and deposit it or use it at another location. This is because there is a possibility that the sand, soil, or dredged material is contaminated. This material can then mix with the cleaner underlying soil, causing the contamination to spread. There is also a risk that the contamination in the soil will be washed out by rainwater and end up in the underlying layer. For this reason, the Ministry of Infrastructure and the Environment has issued theSoil Quality Decree. The purpose of this Decree is to ensure that soil in the Netherlands is managed sustainably. When soil is applied to a site, its quality must be suitable for the (future) use at that location. Furthermore, the quality of the receiving soil must not deteriorate.

The municipalities of Hillegom, Kaag en Braassem, Leiden, Leiderdorp, Lisse, Nieuwkoop, Noordwijk, Oegstgeest, Teylingen, Voorschoten, and Zoeterwoude have established joint regulations for the (temporary) excavation, storage, and use of sand, soil, and dredged material. The joint regulations of these municipalities in the West-Holland region are included in the Soil Management Policy. Information about the Soil Management Policy and the accompanying soil quality maps can be found here: Moving or Reusing Soil and Construction Materials - West-Holland Environmental Agency (odwh.nl).

The Water Board is the competent authority for the disposal of sand, soil, or dredged material into ditches or other surface waters.The Rijnland Water Boardis active in the municipality.