| 1 | Cascade Drilling L P | 96 | 163 | 2,827 |
| 2 | Martell Water Systems Inc. | 78 | 652 | 1,094 |
| 3 | Pacific Coast Well & Pump Inc. | 52 | 92 | 183 |
| 4 | Corrpro Companies Inc. | 52 | 52 | 737 |
| 5 | American Construction And Supply Inc. | 50 | 182 | 1,697 |
| 6 | Castle Well Drilling Inc. | 44 | 44 | 294 |
| 7 | Hennings Bros Drilling Co. Inc. | 34 | 323 | 6,824 |
| 8 | Gregg Drilling LLC | 30 | 30 | 564 |
| 9 | Environmental Control Associates | 25 | 26 | 277 |
| 10 | Gregg Drilling & Testing Inc. | 23 | 521 | 4,828 |
| 11 | Cascade Drilling LP | 22 | 26 | 830 |
| 12 | Altamont Water Well And Pump | 21 | 22 | 90 |
| 13 | National E W P Inc. | 13 | 28 | 431 |
| 14 | Canepa And Sons Inc. | 12 | 29 | 3,178 |
| 15 | Exploration Geoservices Inc. | 11 | 12 | 956 |
| 16 | Weeks Drilling And Pump Co. | 10 | 42 | 14,795 |
| 17 | T S A Drilling Inc. Dba Penecore Drilling | 10 | 26 | 582 |
| 18 | Signal Drilling Company | 9 | 121 | 8,301 |
| 19 | Clear Heart Drilling Inc. | 8 | 27 | 694 |
| 20 | Confluence Environmental Inc. | 6 | 6 | 65 |
| 21 | Maggiora Bros Drilling Inc. | 5 | 35 | 4,676 |
| 22 | Dan's Water Well & Pump Service Inc. | 5 | 15 | 37 |
| 23 | Kvilhaug Drilling & Pump Inc. | 4 | 156 | 328 |
| 24 | Pitcher Drilling Co. | 4 | 137 | 1,232 |
| 25 | Guardino Well Drilling Inc. | 4 | 8 | 1,756 |
| 26 | Farwest Corrosion Control Company | 4 | 7 | 2,667 |
| 27 | Castle Construction & Well Drilling Inc. | 4 | 5 | 142 |
| 28 | Modern Technology Resources Inc. | 4 | 5 | 44 |
| 29 | Gregory Drilling Incorporated | 4 | 4 | 143 |
| 30 | Woodward Drilling Company Inc. | 1 | 149 | 1,542 |
| 31 | Eaton Drilling Co. LLC | 1 | 7 | 3,792 |
| 32 | Masellis Drilling Inc. | 1 | 1 | 6,093 |
| 33 | Sullivan Drilling Inc. | 1 | 1 | 1,390 |
| 34 | Well Industries Inc. | 1 | 1 | 559 |
| 35 | Wildrose Drilling LLC | 1 | 1 | 102 |
| 36 | Pitcher Services LLC | 1 | 1 | 117 |
| 37 | Taber Drilling | 1 | 1 | 87 |
| 38 | Dejesus Pump & Well Drilling Inc. | — | 1,010 | 1,157 |
| 39 | Cascade Drilling Inc. - California | — | 283 | 3,167 |
| 40 | Motheral Well Drilling | — | 179 | 198 |
| 41 | Dejesus Ernest Pump And Well Drilling Service | — | 175 | 178 |
| 42 | Pacific Coast Drilling | — | 158 | 262 |
| 43 | Mel Meyer | — | 155 | 101,127 |
| 44 | H A M Drilling Inc. | — | 123 | 273 |
| 45 | Glenn Martell & Son Inc. | — | 116 | 164 |
| 46 | James P Treadway | — | 86 | 87 |
| 47 | W D C Exploration & Wells | — | 74 | 2,421 |
| 48 | Canada Pump Sales & Service Inc. | — | 63 | 73 |
| 49 | S A Andresen All Terrain Exploration | — | 62 | 468 |
| 50 | Tom Hunt Drilling Co. | — | 55 | 418 |
| 51 | Dodson Contracting Co. | — | 55 | 113 |
| 52 | Westervelt Well Drilling | — | 54 | 122 |
| 53 | American Drilling | — | 53 | 970 |
| 54 | Vironex, Inc. | — | 42 | 649 |
| 55 | Calwater Drilling Company Inc. | — | 41 | 5,429 |
| 56 | Western Well Drilling Co. Ltd | — | 35 | 842 |
| 57 | Kenn Alexanderson | — | 33 | 33 |
| 58 | Moss Roscoe Company | — | 29 | 1,220 |
| 59 | W T Page | — | 29 | 31 |
| 60 | Huckfeldt Well Drilling Inc. | — | 28 | 1,883 |
| 61 | V & W Drilling | — | 28 | 310 |
| 62 | Toxicological & Environmental Associates Inc. | — | 26 | 26 |
| 63 | Layne Christensen Company | — | 25 | 2,363 |
| 64 | Coastside Drilling & Pump Company | — | 25 | 131 |
| 65 | Fisch Brothers Drilling, Inc. | — | 23 | 6,397 |
| 66 | Canada Bros | — | 23 | 25 |
| 67 | Resonantsonic International Inc. | — | 20 | 397 |
| 68 | West Hazmat Drilling Corp | — | 19 | 1,702 |
| 69 | Jim's Pump & Drilling | — | 19 | 157 |
| 70 | Aqua Science Engineers Inc. | — | 19 | 131 |
| 71 | Boart Longyear Company | — | 17 | 172 |
| 72 | Spectrum Exploration Inc. | — | 16 | 307 |
| 73 | Precision Sampling Inc. | — | 16 | 234 |
| 74 | C. Cruse Drilling | — | 15 | 301 |
| 75 | Doshier-Gregson Well Drilling Service | — | 15 | 167 |
| 76 | DE Lucchi Well & Pump, Inc. | — | 15 | 157 |
| 77 | Humboldt Drilling & Pump Co. | — | 15 | 131 |
| 78 | Bertram Drilling Inc. | — | 13 | 1,171 |
| 79 | E E Luhdorff | — | 13 | 155 |
| 80 | Cornerstone Pump & Well Inc. | — | 13 | 90 |
| 81 | Doshier And Gregson Drilling Inc. | — | 12 | 489 |
| 82 | Geoloop Drilling/Tom Moreland | — | 12 | 32 |
| 83 | Guardino Pump & Well | — | 11 | 482 |
| 84 | Datum Exploration Inc. | — | 10 | 223 |
| 85 | Trinity Source Group Inc. | — | 10 | 67 |
| 86 | Layne-Western Co. Inc. | — | 9 | 255 |
| 87 | Mitchell Drilling Environmental Corp | — | 9 | 199 |
| 88 | Bc2 Environmental LLC | — | 8 | 435 |
| 89 | Thomas F Madsen | — | 8 | 128 |
| 90 | R Barrick For Great Sierra | — | 8 | 55 |
| 91 | Mcgann | — | 8 | 34 |
| 92 | Bradley & Sons Inc. | — | 7 | 3,631 |
| 93 | Johnson Drilling Co. | — | 7 | 11,872 |
| 94 | Doshier-Gregson Inc. | — | 7 | 1,156 |
| 95 | All Well Abandonment | — | 7 | 607 |
| 96 | Dyna Drill International Inc. | — | 7 | 115 |
| 97 | Acme Drilling Company | — | 6 | 1,439 |
| 98 | Williams Well Drilling | — | 6 | 376 |
| 99 | Bayland Drillers | — | 6 | 317 |
| 100 | Ase Drilling Inc. | — | 6 | 82 |
| 101 | Enprobe Environental Direct Push & Drilling Services | — | 6 | 76 |
| 102 | Blake Hennings | — | 5 | 1,362 |
| 103 | A A A Drilling Service | — | 5 | 99 |
| 104 | Scott Xxx PC Exploration Inc. | — | 5 | 154 |
| 105 | R E S N A | — | 5 | 37 |
| 106 | Beylik Drilling & Pump Service | — | 4 | 1,267 |
| 107 | R. S. DE Lucohi/ Delucchi Well & Pump | — | 4 | 149 |
| 108 | A R S Fracturing And Drilling Service | — | 4 | 86 |
| 109 | William L Myers | — | 4 | 66 |
| 110 | S I Guardino | — | 4 | 43 |
| 111 | V T S Drilling LLC | — | 3 | 92 |
| 112 | Kile's Well Drilling | — | 3 | 943 |
| 113 | C & N Pump & Well Co. | — | 3 | 697 |
| 114 | Seanaco Inc. | — | 3 | 327 |
| 115 | Fox Loomis Incorporated | — | 3 | 225 |
| 116 | Groundwater Technology | — | 3 | 46 |
| 117 | Taber Consultants | — | 3 | 30 |
| 118 | A B C Liovin Drilling Inc. | — | 2 | 1,282 |
| 119 | Purviance Drillers Inc. | — | 2 | 663 |
| 120 | Hedman Drilling | — | 2 | 126 |
| 121 | Beymer Well Service | — | 2 | 2,921 |
| 122 | Yosemite Falls Well Drilling | — | 2 | 464 |
| 123 | Wayne Drilling Co. | — | 2 | 1,113 |
| 124 | Peter Garicia | — | 2 | 695 |
| 125 | Pacific Gas And Electric Company | — | 2 | 264 |
| 126 | Heer Nar S | — | 2 | 245 |
| 127 | Xxx Soils Exploration SV | — | 2 | 48 |
| 128 | Zim Industries Inc. Dba Bakersfield Well & Pump Co. | — | 1 | 1,721 |
| 129 | Yosemite Falls Inc. | — | 1 | 708 |
| 130 | Fisch Drilling And Pump Inc. | — | 1 | 665 |
| 131 | Myers Brothers Well Drilling Inc. | — | 1 | 2,865 |
| 132 | D & D Drilling Inc. Dba Valley Drilling Co. | — | 1 | 1,282 |
| 133 | Landino Drilling Co. | — | 1 | 151 |
| 134 | Roadrunner Drilling & Pump Company Inc. | — | 1 | 205 |
| 135 | Wilkinson Enterprises Inc. | — | 1 | 445 |
| 136 | Vaca Drilling Co. /Del Crew JR | — | 1 | 2,745 |
| 137 | A & A Gross Drilling | — | 1 | 816 |
| 138 | R & B Drilling | — | 1 | 761 |
| 139 | Freedom General Repair & Pump Shop | — | 1 | 690 |
| 140 | H O Krossa | — | 1 | 681 |
| 141 | John Linn Drilling, Co. | — | 1 | 428 |
| 142 | Maranatha Drilling | — | 1 | 423 |
| 143 | Hunt Tom Drilling & Construction Co. | — | 1 | 112 |
| 144 | V F Bassett | — | 1 | 101 |
| 145 | Precision Drilling Co. | — | 1 | 71 |
| 146 | Lang Pump & Well Company | — | 1 | 60 |
| 147 | Waterwell Plus | — | 1 | 27 |
| 148 | Danville Well Drilling Co. | — | 1 | 27 |