Following a decorahnews.com news story about a hog confinement application, Anne e-mailed, "People ask me what 'master matrix' means exactly."
Mr., Answer Person says, "The master matrix is a scoring system used to evaluate proposed confined animal feeding operations, known as "CAFOs." These can be cattle or cows, but most commonly in Iowa are hogs.
In 1995 the Iowa Legislature ended local control over the permitting process for such operations, giving it to the Iowa Department of Natural Resources instead. It also created "the master matrix," which wrote down a set of standards which would be used in evaluating any application. Since 1995, any proposed CAFO above a certain size must submit a construction permit application, manure management plan, and a master matrix scoring sheet, with points awarded for complying with various standards. The maximum score possible is 880 points, with 440 points being the minimum passing score.
The Iowa Legislature also included a requirement that the DNR must issue a permit to any application which claims to have earned 440 points on the self-scored master matrix form.
The master matrix has been controversial in many Iowa counties because it limits the influence local officials have. Occasionally proposed confinement operations have not been built, but this has largely been because the company proposing to build the CAFO has withdraw its application, not because of a negative ruling by the DNR.
There is currently an effort underway to get next year's Iowa Legislature to modify the master matrix, but that is not a sure thing by any stretch of the imagination.