Arrow

Feasibility Study (FS):

On February 17, 2021, NexGen released its independent Feasibility Study (FS) of the Rook I Project. The FS was completed in accordance with NI 43-101 and includes joint work by leading consultants including: Stantec Consulting Limited, Wood Canada Ltd., and Roscoe Postle Associates Inc., with other technical inputs completed by sub-consultants.

Summary of the Feasibility Study Highlights:

The FS considers the environmental and economic merits from the Arrow Deposit and places the Project as one of the leading global resource projects with an elite ESG profile.

The Arrow Deposit’s unique geological profile and location allows for key optimizations development. The Project is designed as an underground mining operation, with conventional long hole stope mining methods.

The economic base case was developed encompassing a fixed price of US $50/lb U₃O_8:

Table 1 – Outstanding Economics Summary of Arrow Deposit Feasibility Study (based on US $50/lb U₃O₈)

	FS($CAD)
After-Tax NPV @ 8%	$3.47 Billion
After-Tax Internal Rate of Return (IRR)	52.4%
After-Tax Payback	0.9 Year
Pre-Commitment Early Works Captial	$157 Million
Project Execution Captial	$1.143 Million
Total Initial Captial Costs ("CAPEX")	$1,300 Million
Average Annual Production (Years 1-5)	28.8M lbs U3O8
Average Annual After-Tax Net Cash Flow (Life of Mine)	763 Million
Nominal Mill Capacity	1,300 tonnes per day
Average Annual Mill Feed Grade	2.37% U3O8
Mine Life	10.7 Years
Average Annual Operating Cost ("OPEX", Life of Mine)	$7.58 (US $5.69)/lb U3O8

1. The economic analysis was based on the timing of a final investment decision (“FID”) and does not include the Pre-Commitment Early Works Capital, which are costs NexGen intends on expending prior to the FID.  Pre-Commitment Early Works scope includes site preparation, initial freeze hole drilling and the supporting infrastructure (concrete batch plant, Phase I camp accommodations and bulk fuel storage) required to support full Project Execution Capital.
2. FS based on CAD $1.00 = US $0.75 and US $50/lb U₃O₈ price.

NPV and IRR Sensitivity to Uranium Price, table 2:

Uranium Price (US$/lb)	Feasibility Study (Q4-2020 Dollars)				Interim Trend Update (Q4-2023 Dollars)
	Average Annual Free Cash Flow (Y1-5) (C$ Bn)	Payback Period (Years)	IRR (%)	NPV (C$ Billion)	Average Annual Free Cash Flow (Y1-5) (C$ Bn)	Payback Period (Years)	IRR (%)	NPV (C$ Billion)
$100	2.11	0.6	81.6	8.13	2.04	1.0	46.9	6.79
$90	1.90	0.6	76.8	7.20	1.82	1.1	43.4	5.84
$80	1.68	0.7	71.5	6.27	1.61	1.2	39.6	4.89
$70	1.47	0.7	65.8	5.33	1.39	1.3	35.4	3.96
$60	1.25	0.8	59.5	4.40	1.18	1.6	30.7	3.04
$50*	1.04	0.9	52.4	3.47	0.97	2.0	25.2	2.10
$40	0.82	1.1	44.0	2.53	0.76	2.6	18.9	1.19
$30	0.61	1.3	33.8	1.59	0.55	3.8	10.5	0.23

1. Figures above are based on Probable Mineral Reserves of 239.6 million lbs U3O8, as outlined in the 2021 Feasibility Study. Exchange rate assumptions are 0.75:1 (US$:C$). All economic disclosure, including IRR and NPV sensitivities, is derived from the 2021 Feasibility Study. The Interim Trend Update (August 2024) is disclosed as an internally prepared trend report for cost sensitivities; it does not constitute material new scientific or technical information, nor does it alter the base case of US$50/lb U3O8 or provide an economic analysis beyond what is included in the Feasibility Study. The Interim Trend Update is intended to illustrate the impact of cost inflation and capital refinement as the project advances toward construction readiness. As noted in the Feasibility Study, IRR and NPV are most sensitive to uranium price, grade, metal recovery, and exchange rates. Sensitivity analyses are provided for illustrative purposes only; they may not be appropriate for other uses and do not represent forecasts of uranium prices or prices at which uranium produced from the Rook I Project can be sold.
2. 
   *2021 FS Base Case

Arrow Mineral Resource Estimate, Table 3:

FS Mineral Resource
Structure	Tonnage (k tonnes)	Grade (U3O8%)	Contained Metal (U3O8 M lb)
Measured
A2 LG	920	0.79	16.0
A2 HG	441	16.65	161.9
A3 LG	821	1.75	31.7
Total:	2,183	4.35	209.6
Indicated
A2 LG	700	0.79	12.2
A2 HG	56	9.92	12.3
A3 LG	815	1.26	22.7
Total:	1,572	1.36	47.1
Measured and Indicated
A2 LG	1,620	0.79	28.1
A2 HG	497	15.9	174.2
A3 LG	1,637	1.51	54.4
Total:	3,754	3.1	256.7
Inferred
A1 LG	1,557	0.69	23.7
A2 LG	863	0.61	11.5
A2 HG	3	10.95	0.6
A3 LG	1,207	1.12	29.8
A4 LG	769	0.89	15.0
Total:	4,399	0.83	80.7

1. CIM Definition Standards were followed for Mineral Resources, Mineral Resources are reported inclusive of Mineral Reserves.
2. Mineral Resources are reported at a cut-off grade of 0.25% U₃O₈ based on a long-term price of US$50 per lb U₃O₈ and estimated costs.
3. A minimum mining width of 1.0 m was used
4. The effective date of Mineral Resources is June 19^th, 2019
5. Numbers may not add due to rounding.
6. Mineral Resources that are not Mineral Reserves do not have demonstrated economics.

RPA is not aware of any environmental, permitting, legal, title, taxation, socio-economic, marketing, political, or other relevant factors that could materially affect the Mineral Resource Estimate.

Arrow Mineral Resource Estimate, Table 3:

1. CIM definitions were followed for Mineral Reserves.
2. Mineral Reserves are reported with an effective date of January 21^st, 2021.
3. Mineral Reserves include transverse and longitudinal stopes, ore development, marginal ore, special waste and a nominal amount of waste required for mill ramp-up and grade control.
4. Stopes were estimated at a cut-off grade of 0.30% U₃O₈. 
5. Marginal ore is material between 0.26% U₃O₈ and 0.30% U₃O₈ that must be extracted to access mining areas. 
6. Special waste in material between 0.03% and 0.26% U₃O₈ that must be extracted to access mining areas. 0.03% U₃O₈ is the limit for what is considered benign waste and material that must be treated and stockpiled in an engineered facility.
7. Mineral Reserves are estimated using a long-term metal price of US$50 per pound U₃O₈, and a 0.75 US$/C$ exchange rate (C$1.00 = US$0.75).  The cost to ship the yellow cake product to a refinery is considered to be included in the metal price.
8. A minimum mining width of 3.0 m was applied for all long hole stopes.
9. Mineral Reserves are estimated using a combined underground mining recovery of 95.5% and total dilution (planned and unplanned) of 33.8%.
10. The density varies according to the U₃O₈ grade in the block model.  Waste density is 2.464 t/m³. 
11. Numbers may not add due to rounding.

Stantec is not aware of any environmental, permitting, legal, title, taxation, socio-economic, marketing, political, or other relevant factors that could materially affect the Mineral Reserve Estimate.

Mine Plan and Production Profile:

A detailed mine plan based on conventional long-hole stope mining was engineered using Mineral Reserves only.

During the development of the Feasibility Study, geotechnical studies conducted again supported the conventional long hole stoping mining method, including the use of longitudinal and transverse stopes, 30m level spacing, and the nominal stop strike length of 12 metres to 24 metres.