Those who think the nation's water pollution problems are solved may be unaware of the dead zones that form in the Gulf of Mexico every summer. They are just an extreme example of what happens as a result of the cumulative loading of diffuse pollutants like fertilizer on lakes, streams, and estuaries. But industries and some states resist EPA's push to enforce a little-known Clean Water Act provision known as total maximum daily loads (TMDLs).
Writing about TMDLs will be easier once reporters get a new tool previewed at the TRI conference -- known as the DMR Pollutant Loading Tool. It is currently in beta and not publicly released. But EPA engineer Carey Johnston held out hope that the public will see the beta release within months and be asked to comment. It's a tool that's been available to EPA in-house for some time.
Nothing like this has been publicly available before. What's new: it gives reporters themselves the ability to estimate the cumulative impacts of pollution on water bodies.
- A fairly recent and complete description of the Pollutant Loading Tool can be found in a technical support document (see page 35).