The second stratigraphic test well, DB-2, drilled at the Blue Mountain Geothermal Project 30 kilometers (20 miles) west of Winnemucca, Nevada, was successfully completed on April 29, 2004. The hole was drilled under a cost sharing agreement between Noramex Corp. and the US DOE under the GRED II program to explore the geothermal resource to the west of Blue Mountain in an area previously explored for gold.

Noramex drilled DB-1, the first deep stratigraphic test well, to 672.1 meters (2205 feet) in 2002. DB-1 intersected economic temperatures of 145?C (292.5?F) at a depth of 645 m (2115 ft). DB-1 had lost circulation and indications from the temperature survey of high permeability in the almost 366 m (1200 ft) of hole with high temperatures.

DB-2 encountered higher temperatures, 167?C (333?F) at 585.2 m (1920 ft), also with good indication of permeability from lost circulation and from the temperature surveys from 201.17 m (660 ft) to bottom.
Both wells were drilled with close cooperation and assistance from Sandia National Laboratories. The first well tested the resource along a major north-south trending fault. DB-1 was planned with 7î casing cemented to a depth of 120 m (400 ft) and 4 ?î casing cemented to a nominal depth of 250 m (820 ft). Dynatec Drilling Inc. drilled the hole using a Universal Drill Rig 1500, capable of drilling both the rotary and core sections. The upper part of the hole in the cased intervals was planned for rotary drilling and cementing by the displacement method.

Massive zones of lost drilling circulation required constant remedial work and attention in the upper part of DB-1. The loss zones caused difficulty in cementing both the 7" and the 4 ?" casing strings. Shallow, hot fluid was later found to be migrating down behind the 4 ?î casing from a zone near the bottom of the 7î casing indicating that a complete cement bond was not achieved. Drilling of DB-1 took 43 days from spud to completion.

The second well, DB-2, tested faults to the north of DB-1 in a second area of high temperature anomaly closer to the range front. DB-2 was planned to use flooded reverse circulation technique for the single string of 4 ?" casing to be cemented to 200 m. (650 ft.) using the tremmie pipe method.

This method would allow the hole to advance despite lost circulation. Although cementing with tremmie pipe requires an oversize hole, it allows cementing to surface despite the presence of severe loss zone. Below the cemented casing, the hole was to be HQ cored to total depth of 1000 m (3281 ft) using a different rig set up for wireline coring. Noramex relied on information gained from Sandia's research into the use of these techniques to combat the problems of lost circulation, to help make the decision to change the drilling strategy for DB-2.

This plan was very successful and smooth progress allowed DB-2 to be drilled to a depth of 1128 m (3700 ft) or 11% deeper than originally planned in a total of 33 days from spud to completion. Circulation problems in the open hole below the cemented casing, but above the temperature target for the well were controlled using lost circulation materials. A cement plug was finally set after coring through this zone to reduce the potential for down-flow of cool water.

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