_______(applicant name),

We would like to thank you for your interest in our _____(position, internship program). We regret that we do not have a position we can offer you at this time.
We are honored that you interviewed with us and wish you success in your future endeavors. If you have any questions or concerns, please contact me at (847) 991-6200 ext. xxxx.

Sincerely,

CLEAN AIR ENGINEERING