If the hon. Gentleman has constituents who live near operations like this or has visited such operations, he will understand that the dampening down process is highly valuable for local residents because it reduces the dust that lorries introduce into the local environment. It is an additional process with a valuable environmental impact and it is right that we take it into account as a process not related to extraction. We have developed our proposals on that in consultation with the industry, which has broadly welcomed them.
If I may say so to the hon. Member for Epsom and Ewell, the principal environmental impact of the levy lies in its very purpose, which is twofold. Its purpose is, first, to reduce reliance on the quarrying and extraction of virgin aggregates and, secondly, to do that principally by encouraging, through building in fiscal incentives, the industry and its customers to find recycled and alternative materials, which will allow us to scale down the quarrying of virgin aggregates. Alongside that is a determination to build some of the environmental costs of quarrying into the price and cost of quarrying, as I explained to the Committee during the last sitting.
That is the purpose and rationale of the levy and we are starting to see its impact. I quoted the response of McAlpine. A number of other companies are responding to the new regime in a similar way and that is, I think, helping us to feel confident that the levy will achieve its environmental objectives following its operation from 1 April this year.