English to Spanish Tech/Engineering Chemistry; Chem Sci/Eng

Operations that involve mixing, loading, rinsing, or washing of this product into or from pesticide handling or application equipment or containers within 50 feet of any well are prohibited unless conducted on an impervious pad constructed to withstand the weight of the heaviest load that may be positioned on or moved across the pad.
This setback does not apply to properly capped or plugged abandoned wells and does not apply to impervious pad or properly diked mixing/loading areas.

Hola a todos:
El texto es sobre las precauciones en el uso de un pesticida, sé que impervious es impermeable, pero no logro encontrar nada que tenga que ver con el tema.

Gracias a todos