procedure twice until clams are very clean and there is no sand in the bottom of the pot. in a small pan, melt butter over low heat, then add lemon juice, salt and pepper and stir well. set aside to keep warm.
in a large pot combine the two and a half cups water, onion, celery, and bay leaf. bring to a boil and cook for 5 minutes; add clams and cover pot. check in about 5 minutes for clams to be open. discard any clams that don’t open after a few more minutes.
transfer opened clams to a large serving bowl; set aside to keep warm. remove and discard onion, celery 