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History Well 19-2 • Gas flow was monitored for approximately 2 weeks and controlled by pumping heavy mud downhole. Following the control of the flow and recovery of both the NQ and HX steel that was in the hole, a plug was installed at about 200 ft. The hole was reamed to accept 200 ft of 4.5-inch outside diameter casing. The surface casing was cemented in, and a blow-out preventer (BOP) and stripping head were used for the continuation of drilling to total depth (TD). • Cleanup of the site, replacement of the drill rig, and resetting of surface casing was completed by April 24, 1998. Core drilling resumed on April 25, 1998, and proceeded smoothly to TD at 2820 ft on May 5, 1998. • The core hole was advanced with HX drilling tools to a depth of 1479 - bgs. • Smaller diameter NX drilling tools were used to advance the core hole from 1479 ft bgs to TD at 2820-ft bgs. • Rock core was recovered using a 10-ft-long Christensen double-tube core barrel, • Drilling fluid consisted of light polymer. • Core loss was limited to a 126-ft section at the location of the gas blowout. • Core was recovered but not logged or photographed, from 2017- to 2143- ft bgs, due to the fire following the gas blowout. An attempt was made to record a suite of geophysical logs but was unsuccessful. The geophysical tools were initially run in the hole May 6, 1998. The tool stuck at a bridge in the hole at 1610-ft bgs. Several retrieval techniques were attempted, and the geophysical tool was successfully recovered May 9, 1998. • The monitoring well completion was initiated May 10, 1998, but was hampered by gas flowing from the hole. • The gas flow was eventually contained by pumping cement grout into the hole from TD of 2820-ft bgs to 1280-ft bgs. The monitoring well installation was completed May 16, 1998. The core hole was completed as an Upper Aquifer monitoring welt installation as shown in the completion diagram for Well 19-2. • The well completion was constructed with 2' inch, Schedule 80, flush- threaded, )-ring sealed, PVC well casing and 2-inch, Schedule 80, 0.02- inch slotted (20-slot) well screen to a depth of 1280-ft bgs. • A 10-ft screen was placed at the base of the well completion interval from 1270- to 1280-ft bgs. This corresponds to a depth of 72 ft above the top of the A Groove. • Sand pack (clean, #8) was placed from 1280- to 1260-ft bgs. • A bentonite seal was placed above the sand pack interval from 1260- to 1240-ft bgs. • The core hole was cement-grouted from the top of the bentonite seal (1240-ft bgs) to land surtace using a 1-inch tremie pipe to assure complete grout placement. • A steel, flush-threaded extension with a locking steel cap was added to the top of the 4.5-inch surface casing. • A water level measurement was taken on September 21, 1998. The water was 477 ft below the top of the casing at an elevation of 6145.86 ft.