Ants in my pants. Well, not yet, but coming from under baseboard depositing dirt

I'm afraid it's wood from the home's frame too. As you can see I closed off access to the exterior outlet from where there was steady traffic and that was about three weeks ago and they're still coming. This has gradually been increasing over a year. I noticed the dirt from the beginning but didn't take much notice til dead ants were appearing all over the the nearby bathroom(it's a vacant master bedroom) when I noticed they were coming through from the bathroom to the area in the pic. they've been eating from the shown traps but apparently they are super ants and digest poison. Whatever. Someone said they're coming in from under the house where I can't see which makes sense after I closed off that outlet because I haven't found any other trails. Do I gotta get a pro to stick tubes underground to inject some stuff to get them as suggested by friend or do you guys have any suggestions? Thanks

Here's a vid:

https://youtu.be/vE-ESGn9ZRk Oh, and these piles I vacuum up once a week or so.

 

Keep baiting; could be a very large colony or multiple colonies. I suggest putting ant bait stations around exterior as well. They make stations designed for exterior.
Ant bait is only slightly toxic so that the ants can take it back to the colony and spread it around. It works slowly. Maybe add more to the bedroom and bathroom.

Also try the gel baits that come in plastic syringes. You can inject it into the wall voids where the pipes enter/exit. You can inject it under the baseboard, too. Would have been good to inject it in the wall where the outlet is. Don’t seal anything until the problem is solved. You are limiting your access more so than stopping them. Do you have an access panel for the bathtub? If so, remove it and put bait stations in there. That’s always a good spot.

Don’t spray anything as most sprays have a repellency factor which would then be working against the baiting program. If they are eating the bait then it will work.
Keep us posted.

 

Never should have an open outlet like that on the outside like that, it needs a water tight cover and needed to be GFI protected.
Have you seen the ants on the outside of that wall, or just inside?
Scotts® Ortho Bug B Gon Max® Insect Killer Granules (0167050) - Granules - Ace Hardware

 

Yeah, originally, about a month ago I noticed major traffic going in/out of that exterior outlet which is why I gooed it up. Okay, I'll buy some more traps and the syringes. It's just that wherever you read positive reviews on the stuff they're always saying how effective they are, how the ants just flock to them and in two weeks max they're gone, and that's far from what I'm experiencing so far. They're going in the traps, eating I'm assuming, just not like crazy, just like 'mm.. this stuff's okay, queen doesn't like it, but better than nothing'. So maybe it is working but they're just not eating it fast enough. I'll keep trying. Thanx guys