It seems there is now way to get rid of your account. Perhaps try the link and ask for deletion.
URLS:
http://www.datamasher.org
http://www.datamasher.org/contact
Please note that AccountKiller.com is not associated with the business listed on this page. AccountKiller provides easy-to-understand instructions and guides on how to cancel charges and relationships from the list of businesses on our site, we have no affiliation with these businesses.