Moved from Carpenter Ants.

take a look...
http://bugguide.net/node/view/224500#316300
is it the same???

...and even plumper this time--I think you must have had a recent mating flight in your area if you found two queens like this just meandering around within the last couple of days. Tips for recognizing these gals: They're the BIGGEST ants you'll ever see in your region (15-17mm is typical) and the queens of all the carpenter species you'll encounter locally will always have that very diagnostic big boxy thorax with a level topline...viewed from the side, their configuration always reminds me a little of tanker trucks. The biggest or major workers in these species may well have heads that are just as large or even larger than those of the queens, but they never have as much body mass, especially through the thorax. Following is a link to a photo of some (not very good) specimens of pinned Camponotus noveboracensis that'll give you a chance to compare the profiles of a carpenter queen and the two extremes of the worker class...especially note how the thorax toplines differ between the reproductive and the workers, but also how those of the two workers are similar--that smooth, 'wheel-backed' or 'roached' topline is a great way to differentiate the carpenter workers from Formica workers.

http://www.acad.carleton.edu/curricular/BIOL/resources/ant/Cnoveboracensis.html

PS: Unless the foundation or other parts of your house are wooden and actually rotting, I wouldn't worry too much about meandering carpenter queen ants setting up shop in your home.