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NBRI Reports Restoration of Natural Airflow Throughout Tunnel System at Ruby Gold Mine

North Bay Resources Inc. ("North Bay" or the "Company") is pleased to report that the crew at the Ruby Mine tunnel rehab project has successfully breached the last remaining air blockage in the tunnel, thereby achieving a major milestone with the restoration of natural airflow throughout the entire length of the Ruby tunnel system.

The restoration of natural airflow is of critical importance before any mining operations can commence, and was one of our highest priorities when the Ruby tunnel rehab began in November 2011. In addition to providing the full underground ventilation that is so essential to a mining operation, the importance of this milestone is equally significant in that the breakthrough also facilitates access to the secondary exit at the Lawry Shaft, a vital mine safety consideration.

We currently estimate that there remains another 150 feet or so of the serpentinite belt that needs to be mucked and retimbered before the crew can advance to the 4900 level to evaluate the entrances to the Black Channel where we plan to begin mining operations. This work is expected to take several more weeks. As previously explained in a Company press release dated July 23, 2012, the section of the tunnel where the rehab work has been ongoing is on the west side of the Melones Fault, the primary controlling structure that defines the Motherlode system of Northern California. The geological lithology of this western section is characterized by long stretches of serpentinite, which is a brittle rock structure prone to fracturing and cave-ins. To help insure that mining operations are not interrupted from falling rock from the serpentinite roof, a great deal of care has been taken to retimber this part of the tunnel as much as is deemed prudent, and in some areas installing new timbering to further reinforce the roof and ribs of the tunnel. This has been a slow and tedious process done with the utmost of caution to maximize the safety of the miners, but we are now within sight of completing the task.

Upon reaching the 4900 vein, we will cross over to the eastern side of the Melones Fault and into the approach to the Black Channel. It is worth noting that much of the gold produced from vein deposits of the Motherlode has been mined from the eastern side of the Melones Fault, a geological structure that runs through the entire length of the Ruby property. The geological lithology of the eastern side of the Melones Fault is characterized as a slate structure, which has an inherent stability that is more self-supporting. Whether additional timbering or other roof support beyond that point is needed remains to be seen, but we expect any additional rehab work that might still be required will proceed at a much faster pace once we reach that section of the tunnel. Upon reaching the 4900 Vein, we will have installed over 80,000 board feet of new timbering. We will also have installed almost 5,000 feet of new ventilation duct to support the rehab work, most of which will no longer be needed now that natural ventilation has been established.

As always, we will continue to keep shareholders informed of our operational progress as we proceed forward towards completion of the tunnel rehab project and the start of production this summer.

North Bay CEO Perry Leopold commented, "When we first began the rehab project in 2011, we knew there was an obstruction in the tunnel that was blocking the air flow from the secondary exit at the Lawry Shaft. We also knew that whatever was obstructing the natural airflow needed to be cleared before we could begin mining. We thought it would take a minimum of 4 to 6 weeks to clear. What we did not know was whether the first blockage was the only one, or if there were more blockages beyond it. When we got past that first one, there was still no air flow, and we found another obstruction upstream, then another, and another. No one knew and no technology exists to show what was beyond each blockage, and whether the next one was the last one or not. As it turned out, it took almost 2 years to clear and retimber over two dozen blockages, some small and some large, but I am extremely pleased to report that one by one we finally got it done. I can't say enough about the determination and professionalism of our crew who attacked each obstacle head on and carefully cleared it from our path while reinforcing the tunnel to provide for safe mining conditions once we begin production. We are indeed fortunate to have a great team of experienced miners, and we expect that shareholders will benefit for years to come from their tireless efforts."

About The Ruby Gold Project

The Ruby Mine, a/k/a the Ruby Gold Project, is a fully-permitted underground placer and lode mine located near Downieville in Sierra County, California that is known to have produced over 350,000 ounces of gold since the 1850's, and which is considered to be part of the northern extension of the historic Mother Lode system. The Ruby Property covers approximately 1,755 acres, only a small portion of which has been explored to date. The property consists of the subsurface mineral rights of two patented claims totaling approximately 435 acres and 30 unpatented claims containing approximately 1,320 acres. The equipment, fixed assets, and infrastructure in place include a 1,000 yard per day placer wash plant, 50-ton per day quartz mill, 6,000 feet of tracked haulage, and related support equipment needed for underground mining operations. The property also features an excellent system of roads, is accessible via paved highway from Reno or Sacramento, has abundant water and timber available for mining purposes, and has PG&E power available on-site. For further information on the Ruby Mine, please visit the Ruby page on the North Bay website at


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