This German concept is impossible to translate concisely because it is a specific class of persons which is unknown and unused in Common Law jurisdictions. The closest analogous concept of disruption or danger is in the area of "nuisance". In many nuisance cases, the person causing the nuisance in the US is called "responsible party" or himself called a "nuisance". In the context of environmental law, the person causing the problem will typically be referred to as "polluter" or "owner". We therefore recommend using this neologism with a short definition (like the one here) entered in a parenthetical immediately after the first time the German term is encountered in the source text being translated.