Pumping during day-long workshop?

PickyNikki

I'm going to a workshop tomorrow and leaving DD for the first time. I've pumped what I hope is enough for tomorrow while I'm gone (my mom is babysitting). The workshop starts at 10, so I plan to pump at lunch time and any breaks as necessary. I'm not sure I will have a place to go other than the rest room, so may go out to my car if need be. 

I'm not sure I will have time or a place to clean the parts after each pumping session. Is it ok to leave them and use again and clean everything when I get home? Also, will the milk I pump be ok in the cooler alone? (I will not have access to a fridge.) Or should I plan on dumping it? I'm mainly concerned about keeping up my supply, and don't so much need the milk itself (though it would be nice to keep it if I can).

Thanks in advance.