benchmark, date, observer, organization, receiver, receiver_sn, receiver_type, antenna, antenna_sn, dome, height (m), slant height (m), interval, first_observation (s)
 ashc 81.5_1981_USGS, 2000-08-06,  SEO ,  U So Cal / Ariz Stat,  ASHTECH Z-XII3,  203,  CD00,  ASH700936E_C,  364,  NONE, 0.4421, 0.5133, 0, 30
 ashc 81.5_1981_USGS, 2004-07-08,  DW and BH ,  USGS/Cascades Volcan,  TRIMBLE 5700,  0220290947,  NP,  TRM41249.00,  12560646,  NONE, 0.5499, 0.618, 30, 30
 ashc 81.5_1981_USGS, 2004-07-09,  DW and BH ,  USGS/Cascades Volcan,  TRIMBLE 5700,  0220290947,  NP,  TRM41249.00,  12560646,  NONE, 0.5499, 0.618, 30, 30
 ashc 81.5_1981_USGS, 2011-07-21,  H Bleick T Kent ,  USGS/Cascades Volcan,  TRIMBLE 5700,  0220316024,  2.01,  TRM41249.00,  12560557,  NONE, 0.4127, 0.4876, 15, 30
 ashc 81.5_1981_USGS, 2011-07-22,  H Bleick T Kent ,  USGS/Cascades Volcan,  TRIMBLE 5700,  0220316024,  2.01,  TRM41249.00,  12560557,  NONE, 0.4127, 0.4876, 15, 30
 ashc 81.5_1981_USGS, 2011-07-20,  H Bleick T Kent ,  USGS/Cascades Volcan,  TRIMBLE,  0220316024 ,  5700 2.01,  TRM41249.00,  12560557,  NONE, 0.4127, 0.4876, 15, 18550