Many cleanup standards are intentionally flexibility to allow common sense to play a role. Use this built-in flexibility to your benefit. For instance, one of the most common pollutants in agricultural settings is nitrates. The cleanup limit for nitrate in groundwater is 10 parts per million. But there is no law or regulation limiting nitrates in soil.
Governmental agencies differ wildly in what they require concerning nitrates.
The same flexibility applies to other common contaminants such as diesel. Multiplied over a large site, the savings can add up quickly. In sum, do not just react to governmental demands for further testing, cleanup and monitoring. Plan an active role in your case. Establish your business as one that's careful with money.