The Mammoth Lake 2021 event is about a 3 and 1/2 hour drive from Tom's Dive & Swim. Below is a Google Maps link of possible routes.
Unless you know someone who is already going, most folks just meet at Mammoth Lake around 10:00 AM or so. I usually arrive an hour earlier to setup and claim our spot. We usually finish up around 3:00 PM so that we can get back to Austin at a decent hour and don't have to drive too much at night.
We will be bringing our grill and the dive club will provide snacks, drinks, and lunch. Usually burgers, hotdogs, or something similar. Please let us know if you have any dietary restrictions and we'll do our best to accommodate. Naturally, you are welcome to bring anything else to eat or drink if desired.
This is where the $15/$25 dive club fee comes from. The $20 entrance fee is something that would still need to be paid directly to Mammoth Lake. Note, that there are a few events that may include entrance fees which would be noted in the flyer. Not this one though.
Most places prohibit glass containers for obvious reasons and Mammoth Lake is one of them. Their rules are noted at the below link;
I've never noticed anyone drinking alcohol there but, as an instructor I would recommend waiting a few hours before having alcohol.
Oh, and while you're on their web site, you could complete their release form online to speed up your entry process.
The Tom's Dive and Swim waiver can be found at the below link and can be printed and brought with you, Naturally, we will have extras on site as well.
Please let me know if you have additional questions.