From ottawagreens.ca:

Many thanks to everyone who came out to help clean up Central Park!  I have to admit it is a very clean park to start with - but nonetheless - we still picked up about 7 bags of litter.  Strangely enough, most of the litter was concentrated around the garbage cans (!).  Aside from cigarette butts, the most common litter found was snack bar foils - not the whole slip mind you - just the little corner you rip off first before eating the rest of it.

For the record, from left to right, here are Steven, Paul, Jen, Sarah and Jon.