Child support? tax refund? arrears?

ok my husband owes arrears in child support. his ex lives in washington state and we live in california. he owes about 1500. we filed our taxes and found out that there is an offset so child support will intercept and take what he owes. now my question is will this amount go straight to his ex? or will washington state take the money? because she has received welfare. we dont know if she still is. but she has received help from the state. from what am aware if there is any back support owed to her but the state has been helpin her, does the state keep that money? depending on how much help they gave her, and then she will get the remainder ? hope i didnt confuse anyone. and please save all the negativity with negative comments. you dont know our situation. i just need a plain answer. am all for child support and i agree with it only to a certain extent. now i dont care if they are takin money from our refund. less debt my husband will be in. am just concerned about how the money will distributed. thanks!