instance_of blue hole 
Underwater refers to the ___MASK94___ below the ___MASK80___ of ___MASK45___ where the ___MASK45___ exists in a natural feature ( called a body of ___MASK45___ ) such as an ocean , ___MASK87___ , ___MASK42___ , pond , or river . Texas is the second largest ___MASK41___ in the United States by both area and ___MASK59___ . Geographically located in the south central part of the country , Texas shares borders with the U . S . states of Louisiana to the east , Arkansas to the northeast , Oklahoma to the north , New Mexico to the west , and the Mexican states of Chihuahua , Coahuila , Nuevo León , and Tamaulipas to the southwest , while the Gulf of Mexico is to the southeast . The Pecos ___MASK78___ is a ___MASK78___ that originates in eastern New Mexico and flows into Texas , emptying into the Rio Grande . Its headwaters are on the eastern slope of the Sangre de Cristo ___MASK54___ in Mora ___MASK47___ north of Pecos , NM , at an ___MASK51___ of over 12 , 000 feet ( 3 , 700 m ) feet . The ___MASK78___ flows for 926 miles ( ___MASK95___ , 490 km ) before reaching the Rio Grande near Del Rio . Its drainage basin encompasses about 44 , 300 square miles ( 115 , 000 km ). A ___MASK21___ is the procedure of systematically acquiring and recording information about the members of a given population . It is a regularly occurring and official count of a particular population . The term is used mostly in connection with national population and housing censuses ; other common censuses include agriculture , business , and traffic censuses . The United Nations defines the essential features of population and housing censuses as " individual enumeration , universality within a defined territory , simultaneity and defined periodicity ", and recommends that population censuses be taken at least every 10 years . United Nations recommendations also cover ___MASK21___ topics to be collected , official definitions , classifications and other useful information to co - ordinate international practice . The Blue Hole of Santa ___MASK39___ is a circular , bell - shaped pool east of Santa ___MASK39___ , New Mexico that is one of the most popular dive destinations in the US for SCUBA diving and training . The Blue Hole is an artesian well that was once used as a fish hatchery . It is a clear blue body of water with a constant 64 ° F ( 18 ° C ) temperature and constant inflow of 3000 gallons per minute . While the surface is only 80 feet ( 24 m ) in diameter , it expands to a diameter of 130 feet ( 40 m ) at the bottom . Since Santa ___MASK39___ , New Mexico is at an elevation of 4 , 616 feet , it is necessary for divers to use high - altitude dive tables to compute the dive profile and decompression stops when diving in the Blue Hole . A diving permit is required to use the pool and can be obtained from the city of Santa ___MASK39___ ( $ 8 for a one - week permit ) . Tanks may be filled or rented as well as some equipment at a private dive shop located at the site . Llano Estacado (( meaning Palisaded ___MASK61___ ) Texas / local pronunciation : [ yano estakaðo ], New Mexico / local pronunciation : [ jano estakaðo ]) commonly known as the Staked ___MASK61___ , is a region in the Southwestern United States that encompasses parts of eastern New Mexico and northwestern Texas . One of the largest mesas or tablelands on the North American ___MASK26___ , the elevation rises from in the southeast to over in the northwest , sloping almost uniformly at about . Scuba ___MASK99___ is a ___MASK43___ of underwater ___MASK99___ in which the scuba diver uses a self - contained underwater breathing apparatus ( scuba ) which is completely independent of ___MASK80___ supply , to breathe underwater . Scuba provides the diver with the advantages of mobility and horizontal range far beyond the reach of an umbilical hose attached to ___MASK80___ - supplied ___MASK99___ equipment ( SSDE ). Scuba divers engaged in ___MASK79___ covert operations may be referred to as frogmen , combat divers or attack swimmers . Santa ___MASK39___ is a city in and the county seat of Guadalupe County , New Mexico , United States . The population was 2 , 848 at the 2010 census . It lies between Albuquerque and Tucumcari , situated on the Pecos River at the intersection of Interstate 40 , U . S . Route 54 , and U . S . Route 84 . The city is located west of , but not within , the Llano Estacado or " staked plains " of eastern New Mexico and west Texas . New Mexico is a ___MASK41___ located in the southwestern region of the United States of America . It was admitted to the union as the 47th ___MASK41___ on ___MASK63___ 6 , 1912 . It is usually considered one of the ___MASK70___ States . New Mexico is fifth by area , the 36th - most populous , and the sixth - least densely populated of the 50 United States . A ___MASK77___ is a large and permanent human ___MASK56___ . Although there is no ___MASK89___ on how a ___MASK77___ is distinguished from a town in general English language meanings , many cities have a particular administrative , legal , or historical status based on local law . U . S . ___MASK15___ 54 ( US 54 ) is an east  west United States ___MASK76___ that runs northeast - southwest for ___MASK95___ , 197 miles ( ___MASK95___ , 926 km ) from western Illinois to El Paso , Texas . It enters and leaves Texas twice . The Union Pacific Railroad ' s Tucumcari Line ( former Southern Pacific and Rock Island Lines " Golden State ___MASK15___ ") runs parallel to US - 54 from El Paso to Pratt , Kansas , which comprises about two - thirds of the route . Underwater ___MASK99___ is the ___MASK10___ of descending below the ___MASK45___ ' s surface to conduct underwater activities . In ambient pressure ___MASK99___ , the diver is exposed to the pressure of the surrounding ___MASK45___ , and uses breathing apparatus for scuba ___MASK99___ or surface supplied ___MASK99___ , or when freediving , ___MASK35___ breath - hold . The saturation ___MASK99___ technique reduces the risk of decompression sickness after long duration deep dives . Atmospheric ___MASK99___ suits may be used to isolate the diver from the effects of high ambient pressure . Although not usually considered to be ___MASK99___ , crewed submersibles can extend depth range , while remotely controlled or robotic ___MASK99___ machines can reduce the risk to human divers . A ___MASK14___ is an administrative center , seat of ___MASK16___ , or capital city of a county or civil parish . The term is used in the United States , Canada , Romania , China and Taiwan . In the United Kingdom and Ireland , county towns have a similar function . U . S . ___MASK15___ 84 ( US 84 ) is an east  west U . S . ___MASK76___ . It started as a short Georgia  Alabama route in the original 1926 scheme , but by 1941 it had been extended all the way to Colorado . The ___MASK76___ ' s eastern terminus is a short distance east of Midway , Georgia , at an interchange with Interstate 95 . The ___MASK57___ continues toward the nearby Atlantic Ocean as a county ___MASK57___ . Its western terminus is in Pagosa Springs , Colorado , at an intersection with U . S . 160 . Interstate 40 ( I - 40 ) is a major east - west Interstate ___MASK76___ running through the south - central portion of the United States generally north of Interstate 10 and Interstate 20 but south of Interstate 70 . The western end is at Interstate 15 in Barstow , California ; its eastern end is at a concurrency of U . S . Route 117 and North Carolina ___MASK76___ 132 in Wilmington , North Carolina . It is the third longest interstate in the United States , behind Interstate 80 and Interstate 90 . Much of the western part of I - 40 , from Oklahoma City to Barstow , parallels or overlays the historic U . S . Route 66 , east of Oklahoma City the route generally parallels U . S . Route 64 and U . S . Route 70 . I - 40 runs through many major cities including Raleigh , North Carolina ; Nashville , Tennessee ; Memphis , Tennessee ; Little ___MASK64___ , Arkansas ; Oklahoma City , Oklahoma ; Amarillo , Texas , and Albuquerque , New Mexico .