Member List Go back to directory. Add to Address Book. Matthew L. McCahan Stahl Sheaffer Engineering, LLC Work 301 Science Park Road, Suite 333 State College PA 16803 work Work Phone: 814.733.4402work Cell Phone: 814.233.4200cell Work Fax: 814.233.0046workfax Work Email: mmccahan@sse-LLC.comINTERNET Categories: Members Updated 3 months ago.