volunteers to/for

[Navi]

Let us say some people have volunteered to clean up the beaches.
Would one call them:
1-Volunteers for cleaning up the beaches
2-Volunteers to clean up the beaches
3-Those who have volunteered to clean the beaches

[Dozy]

#1 and #2 would usually pass, and would not be noticed as an error. However, if I'm being very fussy, I find them both slightly awkward. I can't think of a really neat and perfect way of saying this.

#3 (or "People who have ...") is good English, but of course it is not such a compact noun phrase. I prefer "clean up" to "clean" here, but I assume the omission of "up" in #3 was unintentional and not important to your question.