Mendham, New Jersey, United States [Borough]; population was 4,890 in 1990; housing units was 1,777 in 1990; location is 40°46'N 74°36'W; land area is 6.02 square miles (3,854 acres); water area is 0.02 square miles (14 acres); FIPS code is 45330 [SourceCBP]