Underground Delineation Drilling at Northgate Minerals’ Young-Davidson Mining Project Confirms Zone Geometry and Grade

Results Show Potential for Higher "As Mined" Grade from the Underground

VANCOUVER, May 26, 2011 /PRNewswire/ - Northgate Minerals Corporation (TSX: NGX, NYSE Amex: NXG) is pleased to announce results from a highly successful underground delineation drill program at its 100% owned Young-Davidson Mining Project located in northern Ontario.

Delineation drilling was initiated to define the stope limits for underground mining within the Upper Boundary Zone ("UBZ"). Results from the drill program have confirmed the grade, continuity and width of the UBZ, which contains 3.64 million tonnes of ore and is scheduled for mining in the early years of underground production. Young-Davidson is currently forecasting an initial 15-year mine-life with production commencing in 2012 from a small open pit before mining moves underground in 2014. The area of delineation drilling covers approximately half of the ore tonnage in the UBZ.

UBZ Drill Highlights

• The UBZ delineation drill program consisted of 66 holes with much closer-spaced drilling than what was used to develop the initial reserve. When combined with the historic "as mined" ore grade on the property of 3.39 grams per tonne (g/t), results continue to suggest a strong probability that the ore grade will be closer to the historic "as mined" grade when the underground orebody is actually mined. 
• Of the 66 holes that were drilled in the UBZ, 26 holes returned a significant result of greater than 95 gram-metres and 70% of the holes returned greater than 50 gram-metres.
• Hole YR-36: returned 11.13 g/t uncut over 44.0 metres ("m") (estimated 37.0 m true thickness).
• Hole YR-17: returned 6.34 g/t uncut over 44.0 m (estimated 43.6 m true thickness).
• Hole YR-16: returned 5.32 g/t over 54.8 m (estimated 45.9 m true thickness).
• Hole YM10-16: returned 4.64 g/t over 58.8 m (estimated 51.3 m true thickness).
• Drill results reported herein will be used to update reserve and resource estimates at the end of the year.

"The delineation drill program within the Upper Boundary Zone has been extremely successful" commented Ken Stowe, President and CEO. "Results from this delineation program are essential as we move closer to our first gold pour in 2012, as this information gives us confidence in the orebody, confirming the grade, continuity and width of the zone. In addition, the comparison between cut and uncut drill results from the recent drilling continues to indicate that there is strong potential for the actual "as mined" grade of the current underground reserve to be up to 10% higher than our current reserve grade, which we will look for when the first underground ore is delivered to the mill in 2014."

UBZ Delineation Drill Program

The UBZ delineation drill program began in 2008. Results from the 2008 drill program were used in the current reserve and resource estimate, but have not been individually reported before. The program was put on hold in 2009 and part of 2010 as Northgate had sufficient drill information to form its initial proven and probable reserve estimate of 2.8 million ounces of gold¹. Drilling re-commenced in the fall of 2010 with approximately 6,350 m drilled. In total, 66 holes have been completed (28 NQ and 38 BQ diameter core holes) in the near-surface portion of the UBZ.  These holes are required to define final stoping boundaries with increased resolution and to plan for an efficient and safe mining sequence over the life of the mine.

The UBZ in relation to the current Young-Davidson reserve is shown on the longitudinal section in Figure 1.  The UBZ is located on the structural footwall of a steeply south-dipping syenite contact with meta-sediments over an area equivalent to three hectares. The area of infill drilling covers approximately half of the ore tonnage in the UBZ (see Figure 2). The mineralization style is disseminated with pyrite associated with sheeted quartz-pyrite veinlets in well developed potassic alteration.  Delineation drilling has been conducted on sections spaced 15 m to 30 m apart from ramp access located 50 m - 70 m in the footwall of the mineralization. Previous drilling completed to develop the current reserve was wider-spaced (30 m to 45 m centres).

Of the 66 holes completed from the UBZ delineation program, 26 holes returned intervals greater than 95 gram-metres and are presented in Table 1 (in bold). Complete drill results can be found in Appendix 1 at the end of this press release.  Results are presented as interval totals for cut (to 20 g/t gold) and uncut analyses. Delineation drilling for the near-surface sector of the UBZ has been highly successful confirming the grade, continuity and widths of the original resource model and has added new resource potential in the footwall of the UBZ (see Figures 3 - 7) as shown by the red lines appearing outside of the resource outline (in magenta).

Uncut delineation drill results averaged 3.76 g/t gold or 3.39 g/t gold when cut to 20 g/t.  The 11% difference between cut and uncut assays is consistent with the difference noted in the wider-spaced exploration drilling that was used to generate the 2.8 million ounce reserve at Young-Davidson. Capping is a technique that is employed in the estimation of resources and reserves to apply a margin of conservation to these estimates in the event that higher grade nuggets are disproportionately represented in the sparse sampling. The fact that the difference between cut and uncut grades continues to be the same in the closer-spaced delineation drilling that was recently completed combined with the fact that the historic "as mined" grade on the property was 12.7% higher than the current reserve grade, suggests the strong possibility that "as mined" ore grades from the underground orebody will exceed the current reserve grade.

Next Steps

Results from this drill program will be incorporated into the annual reserve and resource update at the end of the year. Delineation drilling on the property is ongoing and future efforts will focus on the upper part of the Lucky Zone ore lenses.

Figure 1 - Young-Davidson Longitudinal Section (looking north). UBZ in red with black outline.

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig1.JPG

Figure 2 - Young-Davidson Upper Boundary Zone

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig2.JPG

Figures 3 - 7 illustrate each drilling section through the UBZ confirming the original geometry and widths determined from the initial 2008 resource work. The red lines are the mineralized portions of the drill holes reported in Table 1 and Appendix 1, while magenta shows the resource outline for the UBZ. Mineralized portions of the drill holes appearing outside of the resource outline demonstrate new resource potential in the footwall of the UBZ. At the west end of the resource, there is a post-mineral diabase dyke, which is actually located in a slightly lower position than originally modeled.

Table 1: Selected Assay Results from UBZ Delineation Drill Program (>95 gram-metres in bold)

Figure 3 - UBZ Drill Section 23510

(Red lines are mineralized portions of the drill holes reported in Table 1. Magenta shows the resource outline for the UBZ. Red lines appearing outside of the resource outline represent new resource potential).

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig3.JPG

Figure 4 - UBZ Drill Section 23540

(Red lines are mineralized portions of the drill holes reported in Table 1. Magenta shows the resource outline for the UBZ. Red lines appearing outside of the resource outline represent new resource potential).

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig4.JPG

Figure 5 - UBZ Drill Sections 23570

(Red lines are mineralized portions of the drill holes reported in Table 1. Magenta shows the resource outline for the UBZ. Red lines appearing outside of the resource outline represent new resource potential).

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig5.JPG

Figure 6 - UBZ Drill Section 23600

(Red lines are mineralized portions of the drill holes reported in Table 1. Magenta shows the resource outline for the UBZ. Red lines appearing outside of the resource outline represent new resource potential).

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig6.JPG

Figure 7 - UBZ Drill Section 23630

(Red lines are mineralized portions of the drill holes reported in Table 1. Magenta shows the resource outline for the UBZ. Red lines appearing outside of the resource outline represent new resource potential).

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig7.JPG

Appendix 1: Complete Assay Results from UBZ Delineation Drill Program

Qualified Persons
The program design, implementation, quality assurance/quality control and interpretation of the results are under the control of Northgate's geological staff, which includes a number of individuals who are qualified persons as defined under NI 43-101. Carl Edmunds, PGeo, Northgate's Exploration Manager, is responsible for the overall supervision of the program.

* * * * * * *

Note to Investors:
The terms "Qualified Person", "Mineral Reserve", "Proven Mineral Reserve", "Probable Mineral Reserve", "Mineral Resource", "Measured Mineral Resource", "Indicated Mineral Resource", and "Inferred Mineral Resource" used in this news release are defined in accordance with NI 43-101.

* * * * * * *

Northgate Minerals Corporation is a gold and copper producer with mining operations, development projects and exploration properties in Canada and Australia.  Our vision is to be the leading intermediate gold producer by identifying, acquiring, developing and operating profitable, long-life mining properties. 

* * * * * * *

Cautionary Note Regarding Forward-Looking Statements and Information:
This Northgate press release contains "forward-looking information", as such term is defined in applicable Canadian securities legislation and "forward-looking statements" within the meaning of the United States Private Securities Litigation Reform Act of 1995, concerning Northgate's future financial or operating performance and other statements that express management's expectations or estimates of future developments, circumstances or results. Generally, forward-looking information can be identified by the use of forward-looking terminology such as "expects", "believes", "anticipates", "budget", "scheduled", "estimates", "forecasts", "intends", "plans" and variations of such words and phrases, or by statements that certain actions, events or results "may", "will", "could", "would" or "might" "be taken", "occur" or "be achieved". Forward-looking information is based on a number of assumptions and estimates that, while considered reasonable by management based on the business and markets in which Northgate operates, are inherently subject to significant operational, economic and competitive uncertainties and contingencies. Northgate cautions that forward-looking information involves known and unknown risks, uncertainties and other factors that may cause Northgate's actual results, performance or achievements to be materially different from those expressed or implied by such information, including, but not limited to gold and copper price volatility; fluctuations in foreign exchange rates and interest rates; the impact of any hedging activities; discrepancies between actual and estimated production, between actual and estimated reserves and resources or between actual and estimated metallurgical recoveries; costs of production; capital expenditure requirements; the costs and timing of construction and development of new deposits; and the success of exploration and permitting activities. In addition, the factors described or referred to in the section entitled "Risk Factors" in Northgate's Annual Information Form for the year ended December 31, 2009 or under the heading "Risks and Uncertainties" in Northgate's 2009 Annual Report, both of which are available on the SEDAR website at www.sedar.com, should be reviewed in conjunction with the information found in this press release. Although Northgate has attempted to identify important factors that could cause actual results, performance or achievements to differ materially from those contained in forward-looking information, there can be other factors that cause results, performance or achievements not to be as anticipated, estimated or intended. There can be no assurance that such information will prove to be accurate or that management's expectations or estimates of future developments, circumstances or results will materialize. Accordingly, readers should not place undue reliance on forward-looking information. The forward-looking information in this press release is made as of the date of this press release, and Northgate disclaims any intention or obligation to update or revise such information, except as required by applicable law.

Cautionary Note to US Investors Regarding Mineral Reporting Standards:
Northgate prepares its disclosure in accordance with the requirements of securities laws in effect in Canada, which differ from the requirements of U.S. securities laws. Terms relating to mineral resources in this press release are defined in accordance with National Instrument 43-101-Standards of Disclosure for Mineral Projects under the guidelines set out in the Canadian Institute of Mining, Metallurgy, and Petroleum Standards on Mineral Resources and Mineral Reserves. The Securities and Exchange Commission (the "SEC") permits mining companies, in their filings with the SEC, to disclose only those mineral deposits that a company can economically and legally extract or produce. The Company uses certain terms, such as, "measured mineral resources" "indicated mineral resources", "inferred mineral resources" and "probable mineral reserves", that the SEC does not recognize (these terms may be used in this press release and are included in the Company's public filings which have been filed with securities commissions or similar authorities in Canada).

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¹ See press release dated January 25, 2010.

SOURCE Northgate Minerals Corporation

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