Environmental regulations for substitute construction materials
As long as the draft for the nationwide regulation in form of the “Ersatzbaustoffverordnung (EBV)” (Directive on Alternative Building Materials) is still under discussion, requirements pertaining to substitute construction materials are applicable on a German federal state level. With regard to the recycling possibilities of mineral waste, most federal states refer to the 1997 and 2003 guideline LAGA M20 of the “Länderarbeitsgemeinschaft Abfall” (i.e. the waste working group of the federal states), but there are also federal states with their own regulations, e.g. North Rhine-Westphalia (NRW) has created its own legal basis for use in applications and quality monitoring through a number of decrees.
Differentiation of material classes
The environmental guidelines define specific material quality classes based on the environmental characteristics of recycled aggregates.
- LAGA M20 differentiates between the following assignment values:
- Z 1 with subcategories Z 1.1 and Z 1.2
- Z 2
- In its own decrees for recycled aggregates, NRW distinguishes between two classes of material:
- RCL I
- RCL II
Local conditions for the use of recycled aggregates
The protection of soil and groundwater is the essential condition for the use of recycled building materials. In general, a distinction is made between applications inside and outside of official water protection areas.
- The use outside of water protection areas is permitted.
- The use of recycled aggregates is prohibited in water protection areas WSG I and II.
- The use in water and flood protection areas of the categories WSG IIIA/HSG III and WSG IIIB/HSG IV is permitted, but requires detailed individual consideration.
- The distance to the groundwater level should amount to at least 1 m; it should reach at least 2 m for classification value Z 1.2 according to LAGA M20.
- In individual cases and depending on the federal state, it may be possible to reduce the required distance to groundwater.