The office environment at Sunoco Logistics is something like out of the 80's/90's in terms of the social and political aspects. Everyone tends to be "defined" by their job title there and for some reason, including a high level manager or exec's name on an email to someone in order for it to get done is the norm here. You have a lot of long-tenured folks - 10+ years and they tend to look at the newcomers as folks that are trying to derail their job. It's constant backstabbing and behind-the-door discussions.
As far as the dress code goes, it's mainly business casual. In 2012 (yes, 2012), they enacted a "casual Friday" which included jeans. Apparently this was a HUGE step for Sunoco Logistics and leadership communicated this and treated this new wave of change as progressive. Really.
Sunoco Logistics was acquired in summer of 2012 by ETP and things went downhill from there. More folks from Sunoco moved over to Sunoco Logistics. Basically, these were the "high performers" that Sunoco Logistics wanted to keep without having to "post out" on open positions. I question this practice as it may border some legality issues. Then our benefits changed. We used to have various options and then we were narrowed down by just 2 or 3 plans. The same-sex benefits were completely wiped away and they essentially went backwards. Oh...but there's still casual Fridays!
If you ever go in for an interview, please be cautious. Your hiring manager will paint this wonderful scenario for you. The first few weeks, everyone is very nice until you decide to question some of their prehistoric processes. That's when the tenured folks will start to resent the newcomer for not conforming with what "already works" and denying a such thing as suggestions, recommendations, or improvements.