Pros
It's really easy work. IE. there isn't much work to do. Most people spend their time chatting it up around the water cooler. If you aspire to underachieve in your life, this is an excellent place to cash in.
Kontras
You have to put in a bunch of time before you can expect to make any money. They don't value education. You start at a low GS and slowly work you way up based on tenure, not job performance. I would not recommend pursuing a career with the EPA if you have a graduate education as they will start you at the same level of an undergrad. They don't have a way to value higher education or outside work experience. Therefore, if you're fresh out of undergrad with no work experience, I would be worth your time to clock-in-clock-out and climb a few GS grades. Otherwise, don't bother.