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UK ground water assessment regulations receive a small, but welcome simplification

The UK regulations for ground water assessments have had a small, but welcome simplification.  For some years, the suite of models known as the FOCUS models have been used in the UK regulatory system.  There are three FOCUS model used: FOCUS-PEARL; FOCUS-PELMO; and FOCUS-MACRO.  All three models have to indicate a ‘pass’ for the authorisation or approval to proceed.  A pass means that the predicted concentration in ground water is below a certain threshold.

What has changed is that FOCUS-MACRO is required less often than used to be the case.

It is still needed for certain crops (including winter cereals, potatoes and a dozen others, known as the Châteaudun crops).  But for other crops, it used to be mandatory whenever the substances stuck firmly to the soil.  In technical language, it was necessary whenever the sorption Koc was at least 100 mL/g.  That requirement has now gone.

Let’s look at how the new system works:

Ground water assessment

The target concentrations have not changed.  The maximum concentration for active substances remains at 0.1 µg/L; for certain metabolites, a higher threshold may be applicable.  If the concentrations are too high, there are a number of approaches that can be applied, usually involving gathering additional data or placing certain restrictions on use.  Enviresearch is well versed in the options here and would be pleased to help you.

The advice from the UK regulator on this topic can be found here.


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