When you receive a message from one of the members from the group,you can't directly reply to this individual by using reply function in your email system.
When you reply, this message actually sends to the everyone on the list.
So please remember that if you only want to send a message to this specific person,you have to copy this person's email address from the email heading.

For example, the following is an email heading that you might see when you receive a message:

From: John Shidler

Reply-To: "for testing purpose"

Date: Tue, 18 Apr 2000 10:16:35 -0500 (CDT)

To: "for testing purpose"

Subject: test

In this example, if you only want to send mail to Mr. John Shidler, you can copy shidler.john@epamail.epa.gov, and send your message to him.