With the growth of the dairy market in the US, manure management (an unpleasant and unpopular topic I realize) has become a critical environmental issue, as dairy cows are prolific in their production of waste.
The problems caused by poor manure management (spreading excessive amounts of manure on fields, allowing manure to accumulate in inadequately prepared, site, and/or sized lagoons, etc) include methane generation, eutrophication of waterways, bacterial contamination of water and food, and contamination of drinking water with nitrogen, bacteria, antibiotics and growth hormones (where used), and air pollution. Huge problems.
Although this released FRQ focuses on the economics of producing methane from manure as an alternative to fossil fuels for production of electricity, the sequestration of manure not only prevents methane from escaping to the atmosphere, it also helps to protect water quality and reduce contamination of food crops. As always when thinking and educating about the environment, it is important to step back and look at the larger picture.
March 14, 2016 UPDATE!
Here is a link to a reformatted version of this activity, using Angularjs.