Here is a quote from a document that was approved by Rome, but you will find it on the USCCB site:When there are extraordinary ministers of Holy Communion, they may consume what remains of the Precious Blood from their chalice of distribution with permission of the diocesan bishop.
To the best of my knowledge, this **portion **of the document, called *Norms for the Distribution and Reception of Holy Communion Under Both Kinds in the Dioceses of the United States of America, *still obtains. Other portions, however, might not. There was a question asked and answered in, oh, maybe 2006 about the purification of vessels. EMHC may not do the purification of vessels.
Here is a page on the USCCB site to help you. You must get an answer that is no older than the end of 2006. An answer before that might not be right. I believe that page was posted after 2006. There is
a pdf here that is from the right time period as well, with Q and A at the end.
Thus, it depends on your bishop. You need to find out for your bishop, I assume. Unless there has been more said since 2006 that I have forgotten about, or that I missed.