Dear …
Allow me to take this opportunity to personally congratulate you for being awarded the __(name of award/medal)__. This prestigious award not only recognizes you for your integrity and honor, but also for the loyalty and commitment that you have diligently exhibited throughout all your duties. It’s an honor for us to have someone in our __(unit/organization/etc.)__ who goes beyond the call of duty as you do. Your dedication to your __(fellow colleagues/team/etc._) __ is admirable.
Without a doubt, many people have benefited from your tireless efforts. It is little wonder that there are multitudes thrilled to see you honored in this way. Your contributions have been outstanding and you are exceedingly deserving of this award.
On behalf of __(name of department/organization/etc.)__ and in appreciation of your exceptional efforts, __(name)__, I extend my congratulations to you on this prestigious honor.
Yours very truly,