Nancy was about 2.75 mi from their house. It was an isolated area, not readily visible even from the paved road. Someone driving in there very well might not have seen her. Those of us who went and looked at the dump site all realized how 'hidden in the open' she was...there is an incline down and she was at the base of that, obscured from the road. And the cul-de-sac itself it a good 1/2 mi or more from the houses that are inhabited, at the end of what is a construction site.
Did Brad take a risk in going to LTF? Yes! Yes he did! Let me ask you this: if Brad did the murder then why did he go to LTF at all? Alternatively, if Brad didn't do the murder, and he could see that Nancy did NOT have her LTF card, then why would he think she did go there? According to him she was out on a 'jog,' having taken nothing with her. His visit to LTF makes no sense in either a guilty or innocent scenario, but in a guilty scenario it adds the purpose of trying to see if he can get her scanned in so she appears on the computer.
And I know they weren't getting along, but seriously...the guy is not worried, and does NOT go looking for her until almost 6 hours later (coincidently when her friend calls and wants to come over to watch the kids). Do you not find that just a bit strange?