Region
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Korea (South)
2
Little Missouri River
2
Long Island
2
Michigan
2
Minnehaha County
2
Minnesota
2
Mississippi Embayment
2
Naval Base Kitsap (Wash.)
2
New York
2
North Carolina
2
Oklahoma
2
Oregon
2
Pacific Area
2
Sacramento River (Calif.)
2
Santa Barbara County
2
Sheyenne River
2
Slovenia
2
Southern States
2
Wyoming
2
Abū Ẓaby (Emirate)
1
Albert Pike Recreation Area
1
Alviso Region
1
Amargosa Desert (Nev. and Calif.)
1
Arctic Ocean
1
Arkansas River Watershed
1
Arnold Air Force Base
1
Arnold Air Force Base (Tenn.)
1
Assateague Island (Md. and Va.)
1
Atlantic Coast (South Atlantic States)
1
Barnstable
1
Barstow
1
Beaufort Sea
1
Big Cypress National Preserve
1
Big Sioux Aquifer
1
Birch Creek (Lemhi County-Butte County)
1
Biscayne Aquifer (Fla.)
1
Bremerton
1
Breton Sound
1
Breton Sound (La.)
1
Broward County
1
Bushy Park Reservoir (S.C.)
1
Cape Cod
1
Cape Lookout National Seashore
1
Cape Lookout National Seashore (N.C.)
1
Cape May County
1
Carraízo Reservoir Watershed
1
Carraízo Reservoir Watershed (P.R.)
1
Cascadia Subduction Zone
1
Cattaraugus Indian Reservation
1
Cedar Rapids
1
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