I am a huge fan of writing to my representatives regarding environmental and waste issues.  I always get a personal response (even if it is from their assistant or intern or volunteer, it makes me feel heard!) I think representatives don't get as much mail/email as one might think.  They probably get more form letters (like when you go to a website and select to have the form letter sent to your representative) than anything so I like to think they appreciate it when people take the time to actually write to them about issues they care about in a personal way.