Rainy River Resources' Project Updated With Higher Grades and Lower Costs

RR.TSX

TORONTO, Aug. 29, 2012 /CNW/ - Rainy River Resources Ltd. ("Rainy River" or the "Company" (TSX: RR)) is pleased to announce receipt of an updated and revised positive Preliminary Economic Assessment ("PEA") for its 100% owned Rainy River Gold Project ("RRGP") in western Ontario, Canada.  The information presented below summarizes the results of a conceptual mine and processing scenario based on the February 24, 2012 National Instrument 43-101 ("NI 43101") mineral resource estimate, which includes assay data up to December 31, 2011.  All currency amounts in this press release are expressed in Canadian dollars ($) unless otherwise noted.

HIGHLIGHTS OF THE UPDATED PRELIMINARY ECONOMIC ASSESSMENT

First 10 Years of Production:

• Average annual production of 308,000 gold ounces and 478,000 silver ounces.
• Average mill head grade of 1.45 g/t of gold, an increase of 50% over the first PEA.
• Average open pit grade improves by 39% to 1.25 g/t of gold with stockpiling of low grade material compared to the November 2011 PEA open pit grade of 0.90 g/t of gold.
• Average underground grade improves by 19% to 4.20 g/t of gold compared to the November 2011 PEA underground grade of 3.52 g/t of gold.
• Average cash costs of US$486 per ounce gold (including royalties and net of silver credits).
• Operating strip ratio of 2.5:1 (excluding overburden and capitalized waste) compared to the November 2011 PEA operating strip ratio of 3.3:1.
• Processing throughput averaging 20,000 tonnes per day (tpd).
• Production is anticipated for early 1H/2016 for the open pit and 2H/2018 for the underground.

Economics

Key Metrics

• Life-of-mine pre-tax net present value ("NPV", at a 5% discount rate) of $846 million, internal rate of return ("IRR") of 21.0% and a payback of 3.8 years based on US$1250 per ounce gold and US$25 per ounce silver.
• In the current metal price environment, pre-tax net present value (NPV 5%) of $1.986 billion, IRR of 36.6% and a payback of 2.2 years¹; Metal price sensitivities are summarized in Table 1.
• Life-of-mine metal production of 3.8 million ounces of gold and 6.8 million ounces of silver at 91.0% gold recoveries and 67.4% silver recoveries.

Open Pit

• Initial pre-production capital costs of $694 million (inclusive of $100 million in contingency).
• Open pit total sustaining capital costs of $340 million (tailings, overburden and waste removal, and equipment).
• Total capital costs in the open pit decline by $245 million from the November PEA.

Underground

• Development capital costs of $67 million, commencing in 2016, drawn from operating cash flows.
• Underground sustaining capital costs of $148 million (development, infrastructure and equipment).

Table 1 - Sensitivities to Metal Prices²

Gold, Silver, US$/oz	Base Case $1250 / $25	$1600 / $30	$1800 / $35	$2000/$40
NPV $ millions	846	1,806	2.364	2,922
IRR %	21.0	34.3	41.1	47.5

1.	Discounted cash flow calculated at a gold price of US$1,667 per ounce and silver price of US$30.37per ounce, with a CDN$/US$ exchange rate of $1.0109.
2.	Sensitivities calculated at a CDN$/US$ exchange rate of 1.05.

Raymond Threlkeld, Rainy River's President and CEO, stated: "Over the last five months, our team has investigated and quantified options ranging from a mill having a capacity of 20,000 tonnes per day to 40,000 tonnes per day, conceptual mine plans sized from 4.1 million ounces gold to 5.7 million ounces of gold, and life spans ranging from 13 to 27 years.

Today, we have chosen the option that represents the lowest risk to our shareholders and the strongest internal rate of return in a $1,250 per ounce gold environment.  The resulting project plan represents one of the highest grade open pits, and highest grade mill throughput of any current Canadian open pit mine development story at 1.26 g/t and 1.45 g/t, respectively.

Our mine plan averages 308,000 ounces of gold annually for the first 10 years from open pit and underground, a high mill head grade at 1.45 g/t over 10 years, and a low open pit operating strip ratio at 2.50:1.

The higher grades mined in the open pit and underground enable the cash costs in the first five and ten years to be US$450 and US$486 per ounce gold, respectively, placing the Rainy River Gold Project's costs in the second lowest quartile of cash costs for gold producers worldwide.

The underground portion of the Project, due to be in full production in the fifth year of the open pit operations, adds over 800,000 ounces of gold at a diluted grade of 4.20 grams per tonne for gold and 5.30 grams per tonne for silver, which represents a gold grade increase of 19% from the last PEA.

The Company will continue to review the potential for future operations to be enhanced by increasing throughput or adding mine life, or both.  This project design, with the exploration potential in our district, makes the Rainy River Gold Project stand out in Canada as a low risk, high return project, while retaining the option to mine more ounces in the future."

AREAS OF UPSIDE POTENTIAL FOR PROJECT

• Potential to extend mine life
• Potential to increase mine/mill throughput
• Expansion at depth, underground
• District exploration upside

RAINY RIVER GOLD PROJECT - PRELIMINARY ECONOMIC ASSESSMENT

Contributors
The independent PEA was prepared through the collaboration of a number of industry-recognized consulting firms, including BBA Inc. ("BBA", Montreal, QC), Golder Associates ("Golder", Vancouver, BC), AMEC Environmental & Infrastructure ("AMEC", Mississauga, ON), Merit Consultants International Inc. ("Merit", Vancouver, BC) and SRK Consulting (Canada) Inc. ("SRK", Toronto, ON). These firms provided resource estimates, design parameters and cost estimates for mine operations, process facilities, major equipment, waste storage, reclamation, permitting and operating and capital expenditures.  A summary of contributors to the PEA is included in Table 2 below.

Table 2 - PEA Contributors

Responsibility Area	Contributor
Geology	Rainy River Resources
Resource Estimate	SRK
Mine Planning	BBA, Golder
Geotechnical, Tailings, Hydrogeology	AMEC
Flow sheet and Plant Design	BBA
Tailings Management Facility	AMEC
Infrastructure, Power Supply	BBA
Construction Management	Merit
Environmental Baseline and Permitting	AMEC
Financial Modeling	BBA

Mineral Resources
The study assumes that both open pit and underground mining methods would be used for resource extraction.  Tables 3 (a) and 3 (b) summarize the February 24, 2012 mineral resource estimate, which forms the basis of the PEA.

Table 3 (a).  Mineral Resources Statement at February 24, 2012

Area	Tonnes (millions)	Grade Au g/t	Grade Ag g/t	Au ounces (millions)	Ag ounces (millions)
Open pit (M&I)	135.93	1.12	2.33	4.92	10.16
Open pit (Indicated, out-of-pit)	11.48	0.81	3.37	0.30	1.24
Underground (M&I)	3.17	4.33	4.93	0.44	0.50
TOTAL M&I	150.58	1.17	2.46	5.66	11.91
Open pit (Inferred, in-pit)	22.68	0.93	2.18	0.68	1.59
Open pit (Inferred, out-of-pit)	64.44	0.67	2.35	1.39	4.87
Underground (Inferred)	1.17	4.12	5.82	0.16	0.22
TOTAL Inferred	88.29	0.78	2.35	2.22	6.68

Mineral resources are reported in relation to an elevation determined from conceptual
pit shells, and not all of the inferred resources lie within the optimized pit shell. Mineral
resources are not mineral reserves and do not have demonstrated economic viability.
All figures are rounded to reflect the relative accuracy of the estimate. All assays have
been capped where appropriate.

Open pit mineral resources are reported at a cut-off grade of 0.35 g/t gold;
underground mineral resources are reported at a cut-off grade of 2.5 g/t gold.
Optimized cut-off grades are based on a gold price of US$1,100 per ounce, a silver
price of $22.50 per ounce and a foreign exchange rate of 1.10 Canadian dollars to
1.0 US dollar.  Metallurgical recoveries include gold recovery of 88% for open pit
resources and 90% for underground resources, with silver recovery at 75%.

The mineral resource statement was prepared by Dorota El-Rassi, P.Eng.
(APEO #100012348) and Glen Cole, P.Geo (APGO #1416), of SRK Consulting
(Canada) Inc., both "independent qualified persons" as that term is defined in
National Instrument 43-101.

Table 3 (b).  Mineral Resources Statement at February 24, 2012, Silver Zone.

Silver Zone	Tonnes ('000 t)	Grade Au g/t	Grade Ag g/t	Grade AuEq g/t	Au ounces ('000)	Ag ounces ('000)	AuEq ounces ('000)
Open pit (Indicated)	126	0.23	48.07	1.07	3.18	654.79	14.57

*Excluded from previous table. Mineral resources are reported in relation to conceptual
pit shells.  Mineral resources are not mineral reserves and do not have demonstrated
economic viability. All figures are rounded to reflect the relative accuracy of the estimate.
All composites have been capped where appropriate.

**Open pit mineral resources are reported at a cut-off of 0.35 g/t gold-equivalent.
Gold-equivalent grade is based on a gold price of US$1,100 per ounce, a silver price
of $22.50 per ounce and a foreign exchange rate of 1.10 Canadian dollar to 1.0 US dollar. 
Metallurgical recoveries include gold recovery of 88% with silver recovery at 75%.

Qualified persons - The mineral resource statement was prepared by Dorota El-Rassi,
P.Eng. (APEO #100012348) and Glen Cole, P.Geo (APGO #1416), of SRK, both
"independent qualified persons" as that term is defined in National Instrument 43-101.
Rainy River's exploration program in Richardson Township is being supervised by Kerry
Sparkes, P.Geo. (APEGBC #25261), Vice-President Exploration and a Qualified Person
as defined by National Instrument 43-101. The Company continues to implement a
rigorous QA/QC program to ensure best practices in sampling and analysis of drill core.

The above section summarizes mineral resources and excludes the impact of mining dilution, which is the incidence of waste rock extracted together with mineralized material.

For the PEA, open pit mining dilution is calculated as 10.23% at 0.17 g/t gold and 1.00 g/t silver. Underground mining dilution is calculated as 10% at 0.32 g/t gold and 0.81 g/t silver.  Open pit resources have been calculated assuming a material loss of 5%. Underground resources have been calculated assuming a material loss of 5%.  With an open pit cut-off grade of 0.30 g/t gold-equivalent, and an underground cut-off grade of 2.5 g/t gold-equivalent, the resulting tonnages and grades for the open pit and underground conceptual mine plans are shown in Table 4:

Table 4.  In-Pit and Underground Mineral Resources in PEA (diluted)

Area	Tonnes (M)	Grade Au g/t	Grade Ag g/t	Au Moz Contained	Ag Moz Contained
Open pit (M&I)	101.2	0.94	2.55	3.060	8.287
Underground (M&I)	6.20	4.22	5.06	0.923	1.107
TOTAL M&I	107.37	1.13	2.69	3.982	9.394
Open pit (Inferred)	8.1	0.65	2.21	0.168	0.573
Underground (Inferred)	0.60	3.95	7.92	0.083	0.168
TOTAL Inferred	8.66	0.88	2.61	0.251	0.741

In-pit and underground Mineral Resources are exclusive of Mineral
Reserves. Mineral Resources that are not Mineral Reserves do not
have demonstrated economic viability.

In-pit Resources have been estimated using a cut-off grade of 0.30
g/t AuEq and Underground Resources have been estimated using a
cut-off grade of 2.5 g/t AuEq.

In-pit Resources have been estimated using a dilution of 10.23% at
0.17 g/t Au and 1.00 g/t Ag and Underground Resources have been
estimated using a dilution of 10% at 0.32 g/t Au and0.81 g/t silver.

In-pit Resources have been estimated using a mine recovery of 95%
and Underground Resources have been estimated using a mine
recovery of 95%.

Mining
The PEA assumes the processing of an average 20,000 tonnes per day of material from a combination of open pit, underground and stockpile reclaiming operations.

The open pit mine and stockpiling reclaim plan is a 16-year plan that utilizes a stockpile strategy to maximize grade to the mill and mines to a depth of 400 metres below surface.

The RRGP open pit is designed as a conventional surface mining operation producing mill feed at a rate of 18,000 to 20,000 tonnes per day. The primary equipment fleet would consist mainly of two 26 m³ hydraulic shovels, two 30 m³ wheel loaders, 220 tonne-class haul trucks, and a fleet of support equipment. Production drilling will be carried out by diesel-powered track-mounted units.  Operating bench heights of 10 metres have been assumed for mining operations.

Over the life of the open pit, a total of 311 million tonnes of waste rock and 72 million tonnes of overburden material would be moved.  During the pre-production period, 19 million tonnes of overburden material and 13 million tonnes of waste rock would be removed as part of development work, with overburden stripping completed within the first 4 years of mill operations.  Waste rock-to-mill-feed operating strip ratios average 2.50 during the first ten years of operations, after capitalizing waste material. Waste material totalling 38 million tonnes ($65.0 million) is to be capitalized during the mine life where the strip ratio exceeds the average waste rock-to-mill-feed ratio of 2.84 for the pit. Mined waste rock and overburden material would be stored in nearby stockpiles or used in dyke construction activities associate with the tailings impoundment.

Underground mining would be conducted with mechanized cut-and-fill (MCAF) methods with 5 metre high lifts, designed to deliver 2,000 tonnes per day of feed to the processing plant.  Underground workings would be developed from a primary 5-by-5 metre ramp access and, over time, from the open pit, as the pit deepens.  A fleet of 5.4 m³ scooptrams and 22 m³ trucks would load and haul the material to surface. Development of the underground mine would start in Year 1 of open pit mine operations, commence small scale production by Year 3, and begin producing at full rates by Year 5.

Both mine areas would deliver material to a central gyratory crusher for primary reduction and delivery to the processing plant.

Metallurgy and Processing
Metallurgical testing has been conducted over a period of almost three years at SGS Canada Inc. in Lakefield, Ontario.  Based on the results, BBA has developed a conventional flow sheet including:

• primary crushing and grinding;
• gravity recovery;
• whole-ore leaching followed by a carbon-in-pulp circuit;
• electro-winning and smelting to produce gold doré.

Major equipment for the processing facility includes a gyratory crusher sized for 20,000 tpd, a 34' x 20' semi-autogenous ("SAG") mill and a 24' x 40' ball mill.  Mill feed would be ground to a P₈₀ size of 75 µm before entering a leaching circuit for final metal recovery.

Metallurgical recoveries for gold and silver over the life of the mine are expected to average 91.0% and 67.4% respectively. One tailings pond is envisioned.

Infrastructure

The RRGP benefits from world-class infrastructure, services and available labour in the immediate area.  The project site is located only 65 km from the town of Fort Frances (population 8,000) and is accessible year-round by a network of sealed provincial highways.

Infrastructure is anticipated to include:

• Plant site and haul roads, gate house, parking, bus station and weigh station;
• Separate administration building;
• Assay lab;
• Mine maintenance garage, warehouse;
• Fuel storage facilities;
• Fresh water supply and fire protection;
• Sewage treatment;
• One tailings pond;
• Construction camp for the project development phase. A camp is not anticipated during operations.
• Power to the project supplied by a new 17 km long 230-kV transmission line connecting to the provincial grid, with total power draw expected to be 54.2 MW at peak production.

Operating and Capital Costs
Total operating costs for the RRGP are summarized in Table 5 (a) as follows:

Table 5 (a) - Average Life of Mine Operating Costs (in Canadian dollars)

Cost Structure	Unit	Costs per Unit
Open pit mining (mineralized and waste rock)	C$ / t mined	$1.89
Underground mining (cut & fill)	C$ / t mined	$70.00
Open pit mining (mineralized and waste rock)	C$ / t milled	$6.36
Underground mining (cut & fill)	C$ / t milled	$4.11
Processing	C$ / t milled	$8.73
General & Administrative	C$ / t milled	$1.00
Refining expenses	C$ / t milled	$0.14
Royalties	C$ / t milled	$0.30
Total	C$ / t milled	$20.64

Total cash costs for the RRGP are summarized in Table 5 (b) as follows:

Table 5 (b): Average Gold Cash Costs¹

Area		Initial 5 Years $US/oz Au	Initial 10 Years $US/oz Au	LOM $US/oz Au
Mining (Open Pit and Underground)^2		$248	$295	$307
Processing		205	194	256
General and Administrative		23	22	29
Refining Expenses		3	4	4
Royalties		3	9	9
Silver Credit		(32)	(39)	(45)
Total Cash Costs		$450	$486	$560

Notes:

1. Includes silver credit and royalty payments.
   
2. During years with high stripping ratios (>2.84), the operating costs associated
   with rock waste material have been capitalized.

The breakdown of open pit and underground pre-production and sustaining capital costs is supplied in Tables 6 and 7, respectively.

Open pit pre-production capital costs include overburden stripping, which is necessary to expose the bedrock material to be mined, as well as waste rock stripping.  Open pit sustaining capital costs include the construction of a tailings dam and certain ongoing overburden stripping to expose mineralized material as the pit expands.

Table 6 - Open Pit Capital Costs

Open Pit Pre-Production Capital	C$M
Overburden Stripping	32
Waste Stripping	27
Process Plant	279
Tailings and Water Management	21
Equipment	27
Site and Mine Infrastructure	85
Indirect Costs	123
Contingency	100
Total	694
Open Pit Sustaining Capital	C$M
Equipment Lease	136
Waste Stripping Costs	65
Overburden Stripping Costs	61
Tailings Dam Construction	88
Other: Closure and Salvage value, net	(10)
Total	340

Table 7 - Underground Capital Costs

Underground Capital	C$M
Development	67
Sustaining	148
Total	215

Environment
The environmental baseline assessment was initiated in 2008, and was followed by extensive annual regional field assessments.

As noted in the November 2011 Preliminary Economic Assessment, AMEC's environmental study to-date suggests that 'no fatal flaws' are indicated for the RRGP.

Rainy River recently commenced the project environmental assessment with the filing of a draft Terms of Reference for the provincial process, and the filing of the draft Project Description for the federal process.

Community
The Company is an active member of the local community supporting a variety of community events and initiatives. Regular public information meetings combined with site tours are some of the ways in which the Company continues to engage and inform the local population as to the project's progress.

The Company has local offices situated both near the project site in the town of Emo, and in Thunder Bay.

In support of aboriginal engagement, the Company announced in April 2012 that it had signed a Participation Agreement ("PA") with the six member nations of the Fort Frances Chiefs Secretariat First Nations. Additional consultations in support of Mine permitting are well underway.

The peak construction workforce would total 480 during the 21-month construction period. Employment levels at the RRGP during operations would vary according to production requirements, but would peak at 571 employees.

Project Economics
The first five years of mining yields cash costs (including royalties and net of silver credits) of US$450 per ounce of gold, placing RRGP in the first quartile of global gold projects, based on published industry cost curves.  In Years 1 - 10, cash costs are US$486 per ounce of gold, placing the RRGP within the second quartile of global gold projects. Life-of-mine cash costs, net of silver credits, after the processing of low-grade stockpiles in years 11 to 16, are calculated to be US$560 per ounce of gold. This life-of-mine average places the project within the second quartile of global gold projects, based on published industry cost curves.

Production volumes and cash costs are shown in Tables 8(a) and (b) and 9 below.

Table 8(a) - Gold and Silver Production Profile: Open Pit ¹

OPEN PIT
Year	Tonnage	Gold Grade	Silver Grade	Gold Production	Silver Production
	000's tonnes	g/t	g/t	000's oz	000's oz
1	6,418	1.37	2.45	260	340
2	7,218	1.37	1.98	293	309
3	7,193	1.46	1.86	311	290
4	7,006	1.20	2.57	247	389
5	6,575	1.02	3.55	198	506
6	6,569	1.11	4.44	215	633
7	6,569	1.13	4.50	220	643
8	6,576	1.24	3.73	243	531
9	6,577	1.22	1.92	239	273
10	6,567	1.38	1.68	270	238
11^2	6,570	0.56	1.94	107	276
12	6,570	0.35	2.01	65	286
13	6,729	0.35	2.01	66	293
14	7,300	0.35	2.01	65	317
15	7,300	0.35	2.01	65	317
16	7,300	0.35	2.01	65	317
17	196	0.35	2.01	2	9
	109,232	0.92	2.52	2,931	5,968

Note:

1. Open pit material is comprised of 68.6 Mt @ 1.26 g/t Au, 2.83 g/t Ag material and a
   stockpile of 40.6 Mt @ 0.35 g/t Au, 2.00 g/t Ag.
2. Stockpile material processing begins.

Table 8(b) - Gold and Silver Production Profile: Underground

UNDERGROUND
Year	Tonnage	Gold Grade	Silver Grade	Gold Production	Silver Production
	000's tonnes	g/t	g/t	000's oz	000's oz
1	-	-	-	-	-
2	-	-	-	-	-
3	100	4.13	2.57	12	6
4	300	4.13	2.57	37	17
5	730	4.13	2.57	89	41
6	730	4.13	2.57	89	41
7	730	4.14	13.69	89	217
8	730	4.13	7.14	90	113
9	730	4.13	6.74	89	106
10	730	4.32	5.73	94	90
11	730	4.36	6.30	92	99
12	730	4.22	2.01	88	32
13	571	4.28	1.67	69	21
14	-	-	-	-	-
15	-	-	-	-	-
16	-	-	-	-	-
17	-	-	-	-	-
	6,811	4.20	5.30	837	782

Table 9 - Combined Open Pit and Underground Production, Cash Costs

Year	Tonnes Milled	Gold Grade	Silver Grade	Gold Production	Silver Production	Cash Costs^1
	000's tonnes	g/t	g/t	000's oz	000's oz	US$/oz
1	6,418	1.4	2.5	260	340	$            415
2	7,218	1.4	2.0	293	309	$            379
3	7,293	1.5	1.9	323	295	$            367
4	7,306	1.3	2.6	284	406	$            495
5	7,305	1.3	3.5	287	547	$            606
6	7,299	1.4	4.3	305	674	$            573
7	7,299	1.4	5.4	310	860	$            533
8	7,306	1.5	4.1	332	644	$            544
9	7,307	1.5	2.4	328	380	$            511
10	7,297	1.7	2.1	364	329	$            441
11^2	7,300	0.9	2.4	199	376	$            663
12	7,300	0.7	2.0	152	317	$            825
13	7,300	0.7	2.0	135	313	$            859
14	7,300	0.3	2.0	65	317	$         1,206
15	7,300	0.3	2.0	65	317	$         1,206
16	7,300	0.3	2.0	65	317	$         1,206
17	196	0.3	2.0	2	9	$         1,206
	116,043	1.11	2.7	3,768	6,750	$            560

Note:

1. Cash costs are inclusive of Royalties and net of silver credits
2. Stockpile material processing begins.

The updated PEA study returns a 21.0% IRR and a pre-tax NPV of $846 M, at a 5% discount rate. Parameters are provided in Table 10 below with sensitivities in Table 11.  The PEA assumes that capital costs commence upon the initiation of construction.

Table 10 - Economic Parameters and Summary of PEA Results

Economic Parameter	Units	PEA Base Case Assumptions
Metal price - Au	US$ / oz	$1250.00
Metal price - Ag	US$ / oz	$25.00
Currency exchange rate	C$ / US$	$1.05
Discount Rate for NPV	%	5%
Development Capital - Open Pit	$ millions	$594
Contingency	$ millions	$100
Sustaining Capital - Open Pit	$ millions	$340
Development Capital - Underground	$ millions	$67
Sustaining Capital - Underground	$ millions	$148
5 year cash cost / oz Au^1	US$/oz Au	$450
10 year cash cost / oz Au^1	US$/oz Au	$486
Net Present Value, pre-tax	$ millions, 5% discount	$846
Internal Rate of Return	%	21.0
Payback period	Years	3.8

1. Including royalties and net of silver credits.

All scenarios in the Preliminary Economic Assessment are preliminary in nature and include Measured, Indicated and Inferred Mineral Resources. Inferred Mineral Resources are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as Mineral Reserves. There is no certainty that the Preliminary Economic Assessment will be realized.

Table 11 - Sensitivities to Metal Prices¹

Gold, Silver, US$/oz	Base Case $1250 / $25	$1600 / $30	$1800 / $35	$2000/$40
NPV $ millions	846	1,806	2.364	2,922
IRR %	21.0	34.3	41.1	47.5

1. Assumes constant exchange rate of 1.05 C$/US$.

Comparison Table
Table 12 below compares metrics from the new PEA against the November 2011 PEA.

Table 12 - PEA Comparison

Parameter	Units	November 2011	August 2012
Mine Life	years	13.3	16
Open Pit Depth	m	500	400
Mill Throughput	ktpd	32	20
Mine plan - open pit		143.9Mt @ 0.9 g/t Au, 1.9 g/t Ag	68.6 Mt @ 1.26 g/t Au, 2.83 g/t Ag
Mine plan - stockpile		--	40.6 Mt @ 0.35 g/t Au, 2.00 g/t Ag
Mine plan - underground		6.36Mt @ 3.5 g/t Au, 5.7 g/t Ag	6.81 Mt @ 4.20 g/t Au, 5.30 g/t Ag
Contained gold	Moz	4.3	4.2
Waste	Mt	586	311
Overburden	Mt	91	72
Waste+Overburden/Mineralized Material	Strip ratio	4.7	3.50
Waste/ Mineralized Material	Strip ratio	4.1	2.84
Waste-Capitalized Waste (Operating)/ Mineralized Material	Strip ratio	3.3	2.50
Recoveries - gold	%	88.5	91.0
Recoveries - silver	%	65	67.4
Year 1 - 10 mill Au grade	gpt	0.97	1.45
Year 1 - 10 Au production	koz/y	311	308
Year 1 - 10 cash costs	USD/oz Au	569	486
Open pit, Pre-production capital	C$ M	681	694
Open pit, Sustaining capital	C$M	598	340
Underground, Development capital ^1	C$M	67	67
Underground, Sustaining capital ^1	C$M	110	148
Pre-tax NPV @ 5%	C$M	786	846
Pre-tax IRR	%	19.4	21.0
Payback	Years	3.4	3.8

1. Funded from free cash flow.
2. Including royalties, net of silver credits.

Opportunities and Risks
Opportunities to improve RRGP project economics include the following:

• The PEA is based on the February 24, 2012 mineral resource cut-off date and does not include subsequent infill drilling completed to date in 2012.  The next resource update is planned for Q3/2012 and is expected to include assays from metreage drilled in the first half of 2012. New data will be incorporated into the upcoming feasibility study and is primarily expected to increase confidence levels of existing ounces. Potential impacts are to mining grade, which improves with confidence levels, and the possible conversion of waste material to mineralized material.

Risks requiring mitigation strategies include:

• Management of construction/engineering and procurement costs, and cost containment.
• Operating risks related to recruitment and training of open-pit and underground workforces
• Currency risk relating to equipment purchases denominated in US currency.

Next Steps
Technical:

• Updated NI 43-101 resource estimate;
• Initiate Basic Engineering.

Exploration

• Focussed exploration of district targets;

Community and Environment:

• Ongoing community engagement programs and consultation with the First Nations to continue;
• Begin development of the Project Environmental Assessment report in support of Mine permitting.

The full NI 43-101 Technical Report for the PEA will be filed on SEDAR within 45 days, and will be posted to Rainy River Resources' website at www.rainyriverresources.com at that time.

Rainy River will hold a conference call on Thursday August 30, 2012 at 9:00 a.m. Eastern Daylight Time.  During the call, senior management will be available to discuss the study and respond to questions from analysts and investors.  To join the call, please dial:

• 1-800-319-4610 in Canada and USA toll-free
• 1-604-638-5340 outside Canada and USA

The conference call will be recorded and available until September 28, 2011. Playback details are as follows:

• 1-800-319-6413 in Canada and USA toll-free
• 1-604-638-9010 outside Canada and USA
• Passcode: 5589 followed by the # sign.

Independent Qualified Persons ("QPs")
Independent QPs from BBA, Golder, AMEC and SRK who have prepared or supervised the preparation of the technical information relating to the Preliminary Economic Assessment include:

• David Runnels, Colin Hardie (BBA)
• Donald Tolfree (Golder)
• David Ritchie, Sheila Daniel (AMEC)
• Glen Cole, Dorota El-Rassi (SRK)

The mineral resource statement was prepared by Dorota El-Rassi, P.Eng. (APEO #100012348) and Glen Cole, P.Geo (APGO #1416), of SRK, both "independent qualified persons" as that term is defined in National Instrument 43-101.

Forward Looking Statements
This news release contains "forward-looking information" as defined in applicable securities laws (referred to herein as "forward-looking statements"). Forward looking statements include, but are not limited to, statements with respect to the cost and timing of the development of the Rainy River project, the other economic parameters of the project, as set out in its preliminary economic assessment; the success and continuation of exploration activities; estimates of mineral resources; acquisitions of additional mineral properties; the future price of gold; government regulations and permitting timelines; estimates of reclamation obligations that may be assumed; requirements for additional capital; environmental risks; and general business and economic conditions. Often, but not always, forward-looking statements can be identified by the use of words such as "plans", "expects", "is expected", "budget", "scheduled", "estimates", "continues", "forecasts", "projects", "predicts", "intends", "anticipates" or "believes", or variations of, or the negatives of, such words and phrases, or statements that certain actions, events or results "may", "could", "would", "should", "might" or "will" be taken, occur or be achieved. Forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause the Company's actual results, performance or achievements to be materially different from any of its future results, performance or achievements expressed or implied by forward-looking statements. These risks, uncertainties and other factors include, but are not limited to, the assumptions underlying the preliminary economic assessment not being realized, decrease of future gold prices, cost of labour, supplies, fuel and equipment rising, changes in equity markets, actual results of current exploration, changes in project parameters, exchange rate fluctuations, delays and costs inherent to consulting and accommodating rights of First Nations, title risks, regulatory risks and uncertainties with respect to obtaining necessary surface rights and permits or delays in obtaining same, and other risks involved in the gold exploration and development industry, as well as those risk factors discussed in the section entitled " Description of Business-Risk Factors in Rainy River's 2011 Annual Information Form and its other SEDAR filings from time to time. Forward-looking statements are based on a number of assumptions which may prove to be incorrect, including, but not limited to, the availability of financing for the Company's exploration and development activities; the timelines for the Company's exploration and development activities on the Rainy River Property; the availability of certain consumables and services; assumptions made in mineral resource estimates, including geological interpretation grade, recovery rates, and operational costs; and general business and economic conditions. All forward-looking statements herein are qualified by this cautionary statement. Accordingly, readers should not place undue reliance on forward-looking statements. The Company undertakes no obligation to update publicly or otherwise revise any forward-looking statements whether as a result of new information or future events or otherwise, except as may be required by law.

For additional information with respect to the key assumptions, parameters, risks and other technical information underlying to the mineral resource estimates and the preliminary economic assessment discussed in this news release, refer to: (i) the technical report entitled "Technical Report for the Rainy River Gold Project, Northwestern Ontario, Canada", dated April 9, 2012, with respect to the mineral resource estimates, available at www.sedar.com; and (ii) the technical report entitled "Preliminary Economic Assessment of the Rainy River Gold Property, Ontario, Canada", with respect to the preliminary economic assessment, to be filed at www.sedar.com.

This new release uses the terms "measured resources", "indicated resources" and "inferred resources". The Company advises readers that although these terms are recognized and required by Canadian regulations NI 43-101, the United States Securities and Exchange Commission does not recognize them. Readers are cautioned not to assume that any part or all of the mineral deposits in these categories will ever be converted in to reserves. In addition, "inferred resources" have a great amount of uncertainty as to their existence, and economic and legal feasibility. It cannot be assumed that all or any part of an inferred mineral resource will ever be upgraded to a higher category. Under Canadian rules, estimates of inferred mineral resources may not form the basis of feasibility or pre-feasibility studies, or economic studies, except for a Preliminary Assessment as defined under NI 43-101. Investors are cautioned not to assume that part or all of an inferred resource exists, or is economically or legally mineable.

Non-GAAP Measures
Cash cost per ounce has no standardized meaning under IFRS.

Qualified Persons

Rainy River's engineering assessment in Richardson Township is being supervised by Garett Macdonald, P.Eng. (PEO #90475344), Vice-President Operations and a Qualified Person as defined by National Instrument 43-101. Garett Macdonald, P.Eng. (PEO #90475344), is also the person responsible for the content of this news release. Rainy River's exploration program in Richardson Township is being supervised by Kerry Sparkes, P.Geo. (APEGBC #25261), Vice-President Exploration, a Qualified Person as defined by National Instrument 43-101.

About Rainy River
Rainy River Resources Ltd. is a Canadian precious metals exploration company whose key asset is the Rainy River Gold Project, a large gold system centred in Richardson Township (part of Chapple Township). As of June 30, 2012, the Company had approximately $81 million in cash and cash equivalents, and remains well funded for its 2012 plans to 1) commence a feasibility level study on the RRGP; 2) continue growing the existing resource through exploration; 3) conduct a condemnation program in areas identified for potential mine facilities; and 4) continue regional exploration. RRGP is very well located in the southwestern corner of northern Ontario, near the U.S. border. It is accessed by a network of roads and is close to hydro-electric infrastructure. The Rainy River district has a skilled labour force and is one of the lowest-cost areas for mineral exploration and development in Canada. The Company is working to advance the early-stage discoveries at its TPK Joint Venture Property, also in Ontario, where it can earn a 51% interest in the property from Northern Superior Resources Inc. Ontario has low political risk and, according to the annual Fraser Institute global survey of the mining industry, has consistently ranked as one of the top jurisdictions embracing mineral development.

RAINY RIVER RESOURCES LTD.

Raymond W. Threlkeld
President & CEO

SOURCE: Rainy River Resources

Indi Gopinathan
Director, Investor Relations 
Telephone:  [phone]
E-mail: [email protected]