IPR file photo by Amy Mayer

A Labor Department proposal could make some nitrogen fertilizer more expensive or harder to find. That has Sen. Chuck Grassley (R-Iowa) asking the Labor Department some questions about its new guidance on chemical storage.

Clay Masters / IPR

This summer, officials in Iowa have been asking farmers to voluntarily reduce the amount of fertilizer they use. That’s because the fertilizer contains nitrates that are being washed into state waterways and creating environmental concerns locally and nationally. The runoff has been particularly bad this year, and the outcry over typical crop practices is growing. To find if Iowa farmers are complying with the government’s request, Iowa Public Radio’s Clay Masters followed the water trail.

Mike Stone / Reuters

The deadly explosion at a fertilizer plant in West, Texas is prompting questions about regulatory oversight there.  In Iowa, officials say fertilizer is only produced at a handful of sites across the state, but many others store it.

A U.S. Environmental Protection Agency spokesman says the agency regulates 700 retail facilities in Iowa that store more than 10,000 pounds of anhydrous ammonia fertilizer, an ingredient that can be particularly volatile.