"This report documents the problems that shooting ranges bring to those who use them, their families, their neighbors, and even to entire communities stuck with the considerable costs of cleaning up the hazards that abandoned ranges leave behind." (VPC)
How many "abandoned" ranges are there? The only two indoor ranges I know of near here (Burlington, North Carolina) are still in business. The only organized outdoor ranges near here are police or skeet/trap ranges - and still in business.
There are far, far more abandoned gas stations and dry cleaners - posing far more environmental problems to groundwater.
VPC calls itself a "national" organization - but never even releases claimed membership numbers.
Scandals of antigun politicians - with how-to guide to "outing!"
I have a range in my back yard. There is a lot of lead in the dirt of my backstop. It does not pose an enviromental hazard as lead in the enviroment will quickly form an insoluble coating of lead oxide. However if the lead is exposed to an acidic enviroment it can solubilize and pose a problem. A little chemical magic can solve that. In the case of my backstop the dirt is a mixture of clay and calcium cabonate (the local topsoil in my area). This will form a basic enviroment and the lead will not go into solution. It will be there long after I have assumed room temperature.
In the case of a new range in an area of soil with high organic content and little calcium carbonate a problem could occur (even then it would be minimal) due to the fact this will cause an acidic enviroment when wet. By simply mixing lime in the soil of the backstop a basic enviroment would be assured and the lead would stay put as a lead oxide.