Method of exposing agricultural substrates (plant matter 10, animal matter 12) to agrochemicals (A) method of decreasing or preventing sub-surface geological matter (20, 22) contamination resulting from exposing agricultural substrates to agrochemicals composition [(A)/(T)] 30 used therein article-of-manufacture including the composition. Includes exposing agricultural substrates to composition including combination (mixture) of an agrochemical and at least one transforming agent capable of decreasing or eliminating concentration of the agrochemical which contacts sub-surface geological matter (at temporally varying times, and at spatially varying depths). Before entering sub-surface geological matter, transforming agent exhibits inactivity for decreasing agrochemical concentration, and inactivity for affecting or/and interfering with agrochemical functionality with respect to agricultural substrates. Transforming agent co-migrates and is co-distributed with agrochemical within and throughout sub-surface geological matter, and exhibits activity for decreasing or eliminating agrochemical concentration therein. Transforming agent activity is exhibited at spatially varying depths, at temporally varying times, within sub-surface geological matter.