Union -- U.S. County in New Jersey Population (2000): 522541 Housing Units (2000): 192945 Land area (2000): 103.289164 sq. miles (267.517696 sq. km) Water area (2000): 2.171768 sq. miles (5.624852 sq. km) Total area (2000): 105.460932 sq. miles (273.142548 sq. km) Located within: New Jersey (NJ), FIPS 34 Location: 40.657752 N, 74.301654 W Headwords: Union Union, NJ Union County Union County, NJ