A representative of the order Chordeumatida, a millipede, but I can't tell the family from the photo. Not many chordeumatidans are native to that part of the US, and even fewer are as big as this one seems to be, although there is not a scale measurement in the photos. Conotylidae is the only native family of decent size in that area, but the specimens evidently lack the dorsolateral knobs that conotylids have. Could this perhaps be an introduced chordeumatidan, a new chordeumatida introduction to the US and North America? Can't really say from just these photos. Rowland Shelley