Evaluating the Impact of Monitoring and Enforcement in the Clean Air Act

Abstract

Although Congress passed the Clean Air Act in 1963 to promote public health and welfare, there has been relatively little research into the effectiveness of its monitoring and enforcement.

This dissertation investigates the impact of monitoring and enforcement on emissions and air quality and examines escalating penalties for repeat violations of environmental regulations.

Chapter I shows that penalties decrease emissions of criteria pollutants—commonly found air pollutants that harm human health and welfare. Previous studies have not examined the impact of monitoring and enforcement on emission of these important pollutants. Using a dataset of nitrogen oxides emissions in California, Chapter I shows that penalties reduce emissions. Facilities that were assessed a penalty in the previous year reduce emissions by 5.60 tons on average, a 7.7% reduction in mean facility emissions. Interestingly, inspections have no significant impact, likely because inspection rates in California are consistently high.

Chapter II shows that penalties improve air quality. Previous studies have found that nonattainment of federal air quality standards, which implies more stringent regulations, improves air quality. No research has directly examined the impact of monitoring and enforcement on air quality. Focusing on California, Chapter II finds that increasing penalties at facilities around an air quality monitor improves air quality. Increasing penalties assessed from the 25th to the 75th percentile of the penalty distribution reduces ambient ozone concentrations by 0.348 parts per billion, a 0.4% reduction in mean ambient ozone concentrations.

Chapter III performs empirical analysis of repeat violations in California and finds limited evidence of escalating penalties. Results show that most facilities are compliant; 71.3% were compliant in at least eight out of the nine years studied. There is no evidence that penalties escalate, and facilities that were in violation for longer periods of time were assessed smaller penalties, on average, per year of violation. This is likely because repeat violations are less severe and do not merit large penalties. Therefore, even though penalties do not escalate, persistent violators might not be the worst actors as their violations are less serious.