In light of the hazards and uncertainties associated with subsurface waste disposal, deep well injection may create pollutional problems.

由下废水处置的危险性和不可靠性，深井注入也会产污染。

At present, trivalent chromium electroplating process has became one of the mostimportant techniques to taking place of the seriously pollutional hexvalent chromiumelectroplating process.

目前，三镀工艺已经成为取代重污染六镀的最重要技术之一。