An employee was reclaiming a liquid lye mixture from the containment area using a shop vac. The employee removed the lid to the shop vac and was attempting to pour the reclaimed potassium hydroxide mix from the shop vac into the reclamation area when he lost his grip on the shop vac and spilled the mix onto his legs. He was not wearing PPE. He suffered a chemical burn to the lower half of his left inner thigh and left inner ankle area.