August 10, 1943: Air Warning Service Station "Jig 4-9" was inactivated. The station used existing facilities operated by the State and private land. The AWS added a portable 14 by 32 cabin to the improvements. At the end of service the State retained the site for continued use for fire detection, the portable cabin was moved to Goodwater where the State desires to retain the building. (Report of the Aircraft Warning Service Stations, May 1, 1944)
1956-58: A lookout was completed on Grass Mountain during the biennium. (1st Biennial Report of the Washington Department of Natural Resources)
National Geodetic Survey
DESIGNATION - GRASS MTN LO PID - SX1580 STATE/COUNTY- WA/KING COUNTRY - US USGS QUAD - CYCLONE CREEK (1986)
DESCRIBED BY US GEOLOGICAL SURVEY 1955 LOCATED ABOUT 9.0 MI E. OF ENUMCLAW, 4.5 MI SSW. OF EAGLE GORGE, 2.0 MI N. OF WHITE RIVER. AT STATE DEPT. OF FORESTRY GRASS MOUNTAIN LOT.
TO REACH FROM INTERSECTION OF COLE AND GRIFFIN STREETS IN ENUMCLAW, DRIVE 0.5 MI SE. ON GRIFFIN STREET TO JCT. WITH U.S. HWY. 410. TURN LEFT 5.5 MI E. ON U.S. HWY. 410 TO SCATTER CREEK TRUCK TRAIL LEFT LEADING N. PASS THROUGH YELLOW STEEL GATE OF WEYERHAUSER TIMBER CO. ALONG SCATTER CREEK TRUCK TRAIL 9.7 MI FOLLOWING MAIN RD. TAKE LEFT FORK UPHILL 0.3 MI. TAKE RIGHT FORK 0.1 MI. TAKE RIGHT FORK 1.2 MI TO TOP OF RIDGE IN PROMINENT SADDLE. TAKE SHARP LEFT TURN UP RIDGE ALONG RD. 0.6 MI TO STATION. (KEY AND PERMISSION TO USE SCATTER CREEK TRUCK TRAIL OBTAINED AT WHITE RIVER MILL ABOUT 3 MI E. OF ENUMCLAW ON U.S. HWY. 410