Mitigation Comparison

Measuring Mitigation

Comparing the emission profiles of facilities in the context of their industry provides insights into the variation in emission mitigation efforts by industry.

The variation in environmental release of harmful chemicals provides insights into a company’s control efforts over time and can highlight risks to the reputation and the operations of companies that have poor environmental controls.

Since our data is collected at the facility level, and since it is broken down by chemical, we can use this granular data to examine closely how companies handle their environmental impact. One other key ingredient of the data is the production ratio of each chemical. Not only do we know how much of a particular chemical was released into the environment and by which disposal method, we also know how much of that chemical was produced at each facility relative to the year before.

We calculate an emission ratio (this year’s emission of the chemical divided by last year’s emission of the same chemical at the same facility) and compare that to the production ratio of that chemical (this year’s production divided by last year’s production).

If an increase in production led to an equivalent increase in releases into the environment, we would expect a scatter chart that plotted production ratios versus emission ratios to show a distribution of data points along a straight line at about a 45 degree angle.

If production increases were wholly unrelated to emission increases, we would expect to see a scatter chatter without a discernible pattern. The placement of each data point would be random.

A random distribution of data points implies that the manufacturer has poor control over the release of chemicals into the environment. A more linear distribution reveals an effort at control, and the slope of the line along which the data points cluster, reveals the efficiency of the control measures. A shallow line shows that an increase in production leads to a proportionately smaller increase in release. A steep line shows the opposite, higher production leads to proportionately higher releases.

Comparing the Hydrochloric Acid releases of two cement manufacturers highlights the difference in environmental controls at the facilities run by these companies. Company A has a linear distribution, Company B a random distribution.

This relationship – between increases in production and increases in environmental release – change over time. A company that used to have more of a linear distribution may change over time to a more random distribution and vice versa. This highlights the importance of historical data because it allows users of the data to judge a company’s behavior not only relative to its peers but also in comparison to its previous conduct.

Comparing production and release ratios over time lets us judge whether companies are doing better or worse than before in minimizing their environmental impact. Taking the same two cement manufacturers, we can see a clear change in mitigation behavior over time, with company A relatively consistent except in the early 2000s, and company B getting worse over time.