Stove Burner Repair Question

Hi, Everyone -- I'm Cats, new to the list and also to home repair and handymanning generally. I'm a homeowner, and I recently caught the bug. I'm starting from ground zero, and looking forward to learning more about tackling small repairs myself, instead of standing around with my thumb in my ear going, "Duhhh, wot now, Chollie?" Only a day's worth of posts, and already I've learned new things. Looking forward to learning more, and maybe even contributing ... in about ten years, LOL. I have two questions, one big and one small. The big question. One of my stove burners broke bad some time ago ... it heats up RED-hot, no matter what the knob setting. I trolled around on the Net and discovered that it probably means the "switch contacts are shorted closed", unquote. This is the big burner nearest to hand, natch, and I miss it desperately! Is this something that is easy to fix? If so, can you advise how to go about repairing it? Or send me to a website that lays out the steps? Bearing in mind that I'll need it explained in baby-repair-talk. Is there a set of switch contacts for each burner? You think it'd be a good idea to replace them all, once I'm in there? The small question: I have an empty bucket with a snap lid that once held "Acryl-Pro Ceramic Tile Mastic". I want to put the bucket to another use, and so I need to wash it out. I have a septic tank. Can the residue in the bucket wash down the drain without causing damage to my system? Many thanks in advance for your help with these! Cats