Santa Monica Mountains National Recreation Area Boundary Adjustment Study Act This bill directs the Department of the Interior to conduct a special resource study of the lands, waters, and interests of the coastline and specified areas adjacent to the Santa Monica Bay in California to evaluate a range of alternatives for protecting the study area's resources, including: expanding and redesignating the Santa Monica Mountains National Recreation Area as the "Santa Monica Mountains and Los Angeles Coast National Recreation Area," or creating a new coastal recreation area designated as the "Los Angeles Coast National Recreation Area."