All Zero-Valent Iron (ZVI) or nano and/or micro scale ZVI emulsion (NZVI) types, which have been applied so far to reductively dechlorinate chlorinated volatile organic compounds in contaminated groundwater, are of technical grade, especially regarding Permeable Reactive Barrier (PRBs), which very often are made from scrap metals of different origins, compositions, and so on. Checking different technical ZVI brands and production batches used for applications in PRBs, a wide range of differing trace element contents is encountered for both the average bulk composition of the particles and the surface compositions. If the batch experiment is repeated again using the actual (differing) production batch of ZVI or NZVI to be charged into a field-scale PRB or to be injected into an aquifer, respectively, and it shows nearly the same value of pseudo first-order rate constant, there would be no concern to actually apply it in the field.