Girl Scouts of Tierra del Oro serves nearly 24, 000 girls and 7, 000 adults in the 12, 000 square-mile region of Amador, Calaveras, Colusa, El Dorado, Glenn, Nevada, Placer, Sacramento, San Joaquin, Sierra, Solano, Sutter, Yolo and Yuba Counties. Main Office 3005 Gold Canal Dr. Rancho Cordova, CA 95670 Phone: 916.638.4475 Fax: 916.638.8452 800.322.4475 San Joaquin Service Center 3620 Hammer Ln.