54. The limit values prescribed by section 53 do not apply to surface water collected within the perimeter of a buffer zone established pursuant to section 18 if an analysis of the surface water shows that there is no compliance with the limit values before the surface water enters the buffer zone.
In that case, the quality of the surface water must not, in relation to the parameters or substances listed in section 53, be deteriorated in any manner before it reaches the outside perimeter of a buffer zone established pursuant to section 18.