Latex/Acrylic Paints are messy - but not hazardous. To dispose of latex paint:
Donate Recolor Paints out of Hanover accepts leftover paint in good condition for a fee of $2.00 per can. "If you would use it, we can use it." Contact: 1-833-RECOLOR (732-6567).
Absorb Large quantities of latex or acrylic paint, stains and wood finishes–more than two inches in the bottom of a can–may be absorbed with clay-based kitty litter, or saw dust or hardening product from a hardware store. Pour kitty litter (or saw dust) into a box or container, then pour the paint into the container and stir. Add kitty litter until you can't stir anymore. Once hardened, place the container with the absorbed paint into your household trash. Recycle open, dry paint cans.
Evaporate Small quantities–less than two inches in the bottom of a can–may be disposed of by allowing the liquid to evaporate. Move the container to a sheltered, outdoor area away from children and pets; remove the lid and allow liquid to dry. Once the liquid evaporates, recycle the open can or discard in the trash. Up to two inches in the bottom of an oil-based paint can may also be disposed of in this manner.
Paint should NEVER be poured down indoor or outdoor drains and is illegal.