Aerius and the ever-expanding nitrogen bump

New nitrogen-sensitive plant species and habitats have probably been added as input for the model, as has been the case in recent years. The result is that the PAS detectors waiting for legalization then buy even more nitrogen than they already saw on their plates.

At first glance, nothing has changed for the PAS reporters since the moment they got their fingers in the door - thanks to the government. They need to be legalized, but cannot because they often lack a minimal amount of nitrogen. This is known, but is mentioned again for clarity.

The sad thing is that something does change in their situation, because over the years they often get further and further away from their goal. They are getting worse with every Aerius update.

Goalposts kept moving
The reason is that the provincial implementation unit BIJ12, in coordination with nature organizations, continually adds new and sensitive nature to feed the model. This means that the hurdle for farmers is growing into a mountain. In Gelderland situations are known where PAS detectors had to purchase additional nitrogen several times over the years and each time they came up short because, with yet another Aerius update, the goal posts had shifted again. This is how the system is set up. Interested citizens are still unable to verify whether the changes are justified. The NDFF database is still not freely accessible.

What also does not help is that farmers who purchase additional nitrogen have to deal with two skimmings: a national one of 30% and a provincial top of 35% to 50%, depending on the specific province. Everything to maintain the downward trend in nitrogen depositions.

Speeding between 0 and 200 kilometers per hour
And all this thanks to legal practice that no longer has any relationship with reality, argues modeling expert Wouter de Heij, mentioned earlier here. First of all, he is very surprised that Aerius ever ended up in the law, because according to him, the uncertainties in the model are absurdly large, from 25% to 124%. The RIVM even admits this himself. Mainly due to great uncertainty about dry deposition. No one knows how big it is or even if it exists. Estimates about this from the RIVM are also not calibrated. De Heij: "If you lose your permit in court due to exceeding the critical deposition value (KDW), which is set at 0,0049 mol, you can compare this with receiving a traffic fine for speeding, somewhere between 0 and 200 kilometers."  

Fertilize the field and watch
He shrugs his shoulders in a similar way about determining the nitrogen sensitivity of habitats according to the method of Bobbink and Van Dobben. "Those people are going to fertilize fields and then see what happens. You cannot attach a KDW to that with the accuracy of a few dozen mills." He attributes the fact that it does happen and that even the judge goes along with it to the fact that people without substantive knowledge started working on it. "The judge judges the procedures, but cannot delve into everything."

Preliminary test is a deceased document
Farmers do not immediately benefit from this science. They have to fend for themselves in court. Action group MOB and friends also promise a new offensive. They also want to keep the permits that have already been issued in Brabant under review. According to them, permits must have been tested with an 'appropriate assessment' and this has not always happened. To demonstrate that an appropriate assessment has been made, the government has drawn up a Nitrogen Preliminary Test Guide, now managed by BIJ12. The sad thing about this guidance is that it sends farmers completely into the woods. The document is supposed to be a so-called 'living document', but in practice it has already died in 2021. It has not been updated and most of the references in it are outdated. Not something to go to court with. Fortunately for the government, it also rejects all liability in advance for errors in the piece. Unfortunately, this is not good for trust, but it is typical of the level of many governments.

Cut-off limit and Aerius from the law
In fact, the only solution to this bizarre situation is for the Netherlands, like Germany, to set a cut-off limit for nitrogen deposition, at a level that is still connected to reality. That would be two digits before the decimal point rather than two digits after it. This is also reflected in TNO reports. Moreover, Aerius must not only leave the RIVM, but also from the law, because the law must be pure and just.
Breaking this impasse requires a fresh look and political will.