What is "grain valley"

Population (2000): 5160
Housing Units (2000): 2022
Land area (2000): 4.800180 sq. miles (12.432409 sq. km)
Water area (2000): 0.006115 sq. miles (0.015838 sq. km)
Total area (2000): 4.806295 sq. miles (12.448247 sq. km)
FIPS code: 28090
Located within: Missouri (MO), FIPS 29
Location: 39.008733 N, 94.207465 W
ZIP Codes (1990): 64029
Note: some ZIP codes may be omitted esp. for suburbs.
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