OET-69 INTERFERENCE STUDY BASED ON A 1 KM CELL SIZE AND 0.5 KM TERRAIN DISTANCE INCREMENT ALONG WITH A STRINGENT MASK. A COPY OF PAGES 1-2 OF THE OET-69 INTERFERENCE STUDY, WHICH INCLUDES THE STUDY PARAMETERS AND STATIONS STUDIES, IS ATTACHED. THE PROPOSED OPERATION WILL PROVIDE THE NECESSARY PROTECTION TO RADIO ASTRONOMY INSTALLATIONS AND FCC MONITORING STATIONS. A NOTIFICATION LETTER FOR THE PROPOSED FACILITY IS BEING SENT TO THE ARECIBO OBSERVATORY (SEE ATTACHMENT).