More than three-fourths of manufacturing facilities that hold environmental permits in the United States conduct compliance audits. The existence of audit privilege and immunity legislation or of a penalty mitigation policy - both of which are designed to encourage greater use of environmental audits - does not appear to be a significant factor in the decision to audit. Facilities conduct audits because they make sense - they help measure compliance with environmental regulations, identify problems internally and correct them before they are discovered by a regulatory agency, provide assurance that waste treatment and control systems are functioning properly, improve a company's overall environmental program, and lower its operating costs and financial risks.
Regulatory agencies routinely work with facilities to help them comply with environmental regulations, whether or not the state has an audit law or policy. Audit legislation or policy may help a regulatory agency monitor the extent of audit activity in a state and allow the agency to focus its limited enforcement resources on facilities that do not audit. The existence of audit legislation or policy does not, however, ensure that an agency is any more aware of the level of audit activity than an agency in a state that has no legislation or policy, except to the degree that the legislation or policy promotes the disclosure of violations. Since facilities that conduct audits do not have to disclose violations, the number of disclosures does not provide an accurate assessment of the level of audit activity. The statutory provision that appears to be most useful in helping an agency track audit activity requiring advance notification that an audit is about to begin.