DNA fingerprinting for groundwater quality is used when traditional tracer components cannot be used to link groundwater contamination to the presence of the landfill.
The technique is based on artificial contamination of groundwater samples in the lab. After artificial contamination, the bacterial population growing on the contamination is analysed at genetic level.
In a next stage, the microbial DNA in the lab is compared to microbial DNA in the groundwater on site. Statistical analysis can reveal possible correlation.
Above shown example shows no correlation between the lab samples (dilution 1 and 0.1) and the sampled monitoring pits, meaning no impact of the landfill.