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  Exhibit 10.6    
    





					
	 	 	 	 	Serial Number

    WYW8385

Date Lease Issued
 March 1, 1971
	
 [SEAL]	
 	
 United States Department of the Interior
 Bureau of Land Management

Wyoming State Office	
 	
 [SEAL]
	

 	
 	
 Coal Lease Readjustment	
 	

 






 PART I: LEASE RIGHTS GRANTED  


This
lease, entered into by and between the United States of America, hereinafter called the lessor, through the Bureau of Land Management, and (Name and
Address)






Cordero
Mining Company

P.O. Box 1449

Gillette, WY 82717-1449 







hereinafter
called the lessee, is readjusted, effective (Date) March 1, 2001, for a period of 10 years and for so long thereafter as coal
is produced in commercial quantities from the leased lands, subject to readjustment of lease terms at the end of each 10-year period. 


Sec. 1.
This lease readjustment is subject to the terms and provisions of the: 


	ý
	Mineral
Lands Leasing Act of 1920, Act of February 25, 1920, as amended, 41 Stat. 437.30 U.S.C.
181-287, hereinafter referred to as the Act:



	o
	Mineral
Leasing Act for Acquired Lands, Act of August 7, 1947, 61 Stat. 913.30 U.S.C.
351-359: 



and to the regulations and formal orders of the Secretary of the Interior which are now or hereafter in force, when not inconsistent with the express and specific provisions
herein. 


Sec. 2.
Lessor, in consideration of any rents and royalties to be paid, and the conditions and covenants to be observed as herein set forth, hereby grants to lessee the exclusive right and
privilege to drill for, mine, extract, remove or otherwise process and dispose of the coal deposits in, upon, or under the following described lands: 





							
	T. 46 N., R. 71 W., 6th P.M., Wyoming 	 	T. 46 N., R. 71 W., 6th P.M., Wyoming 
	 	 	Sec. 2: Lots 5-16;

Sec. 3: Lots 5-11;	 	 	 	Sec. 13: Lots 1-8, 10-16;

Sec. 14: Lots 1-15, NWNW;

Sec. 15: Lots 1-16;

Sec. 22: Lots 1-16;

Sec. 23: Lots 1-15, SWNW;

Sec. 24: Lots 1-8;

Sec. 25: Lots 6-9;

Sec. 26: Lots 1-11;

Sec. 27: Lots 1-16;

Sec. 34: Lots 1-16;

Sec. 35: Lots 1-11.






        Containing
6,600,530 acres, more or less, together with the right to construct such works, buildings, plants, structures, equipment and appliances and the right to use such
on-lease rights-of-way which may be necessary and convenient to the exercise of the rights and privileges granted, subject to the conditions herein provided. 







 

 PART II: TERMS AND CONDITIONS  


Sec. 1.
(a) RENTAL RATE - Lessee shall pay lessor rental annually and in advance for each acre or fraction thereof during the continuance of the lease at the rate of $3.00 for
each lease year. 


(b)
RENTAL CREDITS - Rental shall not be credited against either production or advance royalties for any year. 


Sec. 2
(a) PRODUCTION ROYALITIES - The royalty shall be 121/2 per cent of the value of the coal produced by strip or auger methods and 8 per cent of
the value of the coal produced by underground mining methods. The value of the coal shall be determined as set forth in 43 CFR 3480. Royalties are due to lessor the final day of the month
succeeding the calendar month in which the royalty obligation accrues. 


(b)
ADVANCE ROYALTIES - Upon request by lessee, the authorized officer may accept, for a total of not more than 10 years, the payment of advance royalties in lieu of continued
operations, consistent with the regulations. The advance royalty shall be based on a percent of the value of a minimum number of tons determined in the manner established by the advance royalty
regulations in effect at the time the lessee requests approval to pay advance royalties in lieu of continued operation. 



Sec. 3.
BONDS - Lessee shall maintain in the proper office a lease bond in the amount of $2,092,000. The authorized officer may require an increase in this amount when additional
coverage is determined appropriate. 


Sec. 4.
DILLIGENCE - This lease is subject to the conditions of diligent development and continued operation, except that these conditions are excused when operations under the lease are
interrupted by strikes, the elements, or casualties not attributable to the lessee. The lessor, in the public interest, may suspend the condition of continued operation upon payment of advance
royalties in accordance with the regulations in existence at the time of the suspension. Lessee's failure to produce coal in commercial quantities at the end of the 10 years shall terminate the
lease. If not submitted already, lessee shall submit an operation and reclamation plan pursuant to Section 7 of the Act no later than 3 years after the effective date of this lease
readjustment. 


The
lessor reserves the power to assent to or order the suspension of the terms and conditions of this lease in accordance with, inter alia, Section 39 of the Mineral Leasing Act, 30 U.S.C.
209. 


Sec. 5.
LOGICAL MINING UNIT (LMU) - Either upon approval by the lessor of the lessee's application or at the direction of the lessor, this lease shall become an LMU or part of an LMU,
subject to the provisions set forth in the regulations. 


The
stipulations established in an LMU approval in effect at the time of LMU approval will supersede the relevant inconsistent terms of this lease so long as the lease remains committed to the LMU. If
the LMU of which this lease is a part is dissolved, the lease shall then be subject to the lease terms which would have been applied if the lease had not been included in an LMU. 


Sec. 6.
DOCUMENTS, EVIDENCE AND INSPECTION - At such times and in such form as lessor may prescribe, lessee shall furnish detailed statements showing the amounts and quality of all
products removed and sold from the lease, the proceeds therefrom, and the amount used for production purposes or unavoidably lost. 


Lessee
shall keep open at all reasonable times for the inspection of any duly authorized officer of lessor, the leased premises and all surface and underground improvements, works, machinery, ore
stockpits, equipment, and all books, accounts, maps, and records relative to operations, surveys or investigations on or under the leased lands. 


Lessee
shall allow lessor access to and copying of documents reasonably necessary to verify lessee compliance with terms and conditions of the lease. 


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While
this lease remains in effect, information obtained under this section shall be closed to inspection by the public in accordance with the Freedom of Information Act (5 U.S.C. 552). 



Sec. 7.
DAMAGES TO PROPERTY AND CONDUCT OF OPERATIONS - Lessee shall comply at its own expense with all reasonable orders of the Secretary, respecting diligent operations,
prevention of waste, and protection of other resources. 


Lessee
shall not conduct exploration operations, other than casual use, without an approved exploration plan. All exploration plans prior to the commencement of mining operations within an approved
mining permit area shall be submitted to the authorized officer. 


Lessee
shall carry on all operations in accordance with approved methods and practices as provided in the operating regulations, having due regard for the prevention of injury to life, health, or
property, and prevention of waste, damage, or degradation to any land, air, water, cultural, biological, visual, and other resources, including mineral deposits and formations of mineral deposits not
leased hereunder, and to other land uses or users. Lessee shall take measures deemed necessary by lessor to accomplish the intent of this lease term. Such measures may include, but are not limited to,
modification to proposed siting or design of facilities, timing of operations and specification of interim and final reclamation procedures. Lessor reserves to itself the right to lease, sell or
otherwise dispose of the surface or other mineral deposits in the lands and the right to continue existing uses and to authorize future uses upon or in the leased lands, including issuing leases for
mineral deposits not covered
hereunder, and approving easements or rights-of-way. Lessor shall condition such uses to prevent unnecessary or unreasonable interference with rights of lessee as may be
consistent with concepts of multiple use and multiple mineral development. 


Sec. 8.
PROTECTION OF DIVERSE INTERESTS AND EQUAL OPPORTUNITY - Lessee shall pay when due all taxes legally assessed and levied under the laws of the State or the United States; accord
all employees complete freedom of purchase; pay all wages at least twice each month in lawful money of the United States; maintain a safe working environment in accordance with standard industry
practices; restrict the workday to not more than 8 hours in any one day for underground workers except in emergencies; and take measures necessary to protect the health and safety of the
public. No person under the age of 16 years shall be employed in any mine below the surface. To the extent that laws of the State in which the lands are situated are more restrictive than the
provisions in the paragraph, then the State laws apply. 


Lessee
will comply with all provisions of Executive Order No. 11246 of September 24, 1965, as amended, and the rules, regulations, and relevant orders of the Secretary of Labor. Neither
lessee nor lessee's subcontractors shall maintain segregated facilities. 


Sec. 9.
(a) TRANSFERS 


	ý
	This
lease may be transferred in whole or in part to any person, association or corporation qualified to hold
such lease interest.



	o
	This
lease may be transferred in whole or in part to another public body, or to a person who will mine the coal
on behalf of, and for the use of, the public body or to a person who for the limited purpose of creating a security interest in favor of a lender agrees to be obligated to mine the coal on behalf of
the public body.



	o
	This
lease may only be transferred in whole or in part to another small business qualified under 13 CFR 121. 



Transfers of record title, working or royalty interest must be approved in accordance with the regulations. 


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(b)
RELINQUISHMENT - The lessee may relinquish in writing at any time all rights under this lease or any portion thereof as provided in the regulations. Upon lessor's acceptance of the
relinquishment, lessee shall be relieved of all future obligations under the lease or the relinquished portion thereof, whichever is applicable. 


Sec. 10.
DELIVERY OF PREMISES, REMOVAL OF MACHINERY, EQUIPMENT, ETC. - At such time as all portions of this lease are returned to lessor, lessee shall deliver up to lessor the land
leased, underground timbering, and such other supports and structures necessary for the preservation of the mine workings on the leased premises or deposits and place all workings in condition for
suspension or abandonment. Within 180 days thereof, lessee shall remove from the premises all other structures, machinery, equipment, tools, and materials that it elects to or as required by
the authorized officer. Any such structures, machinery, equipment, tools, and materials remaining on the leased lands beyond 180 days, or approved extension thereof, shall become the property
of the lessor, but lessee shall either remove any or all such property or shall continue to be liable for the cost of removal and disposal in the amount actually incurred by the lessor. If the surface
is owned by third parties, lessor shall waive the requirement for removal, provided the third parties do not object to such waiver. Lessee shall, prior to the termination of bond liability or at any
other time when required and in accordance with all applicable laws and regulations reclaim all lands the surface of which has been disturbed, dispose of all debris or solid waste, repair the offsite
and onsite damage caused by lessee's activity or activities incidental thereto, and reclaim access roads or trails. 


Sec. 11.
PROCEEDINGS IN CASE OF DEFAULT - If lessee fails to comply with applicable laws, existing regulations, or the terms, conditions and stipulations of this lease, and the
noncompliance continues for 30 days after written notice thereof, this lease shall be subject to cancellation by the lessor only by judicial proceedings. This provision shall not be construed
to prevent the exercise by lessor of any other legal and equitable remedy, including waiver of the default. Any such remedy, or waiver shall not prevent later cancellation for the same default
occurring at any other time. 


Sec. 12.
HEIRS AND SUCCESSORS-IN-INTEREST - Each obligation of this lease shall extend to and be binding upon, and every benefit hereof shall inure to the heirs,
executors, administrators, successors, or assigns of the respective parties hereto. 


Sec. 13.
INDEMNIFICATION - Lessee shall indemnify and hold harmless the United States from any and all claims arising out of the lessee's activities and operations under this lease. 


Sec. 14.
SPECIAL STATUTES - This lease is subject to the Federal Water Pollution Control Act (33 U.S.C. 1151 - 1175; the Clean Air Act (42 U.S.C. 1957 et. seq.); and to all
other applicable laws pertaining to exploration activities, mining operations and reclamation, including the Surface Mining Control and Reclamation Act of 1977 (30 U.S.C. 1201 et. seq.). 



SEC. 15.
SPECIAL STIPULATIONS - In addition to observing the general obligations and standards of performance set out in the current regulations, the lessee shall comply with and be
bound by the following special stipulations. These stipulations are also imposed upon the lessee's agents and employees. The failure or refusal of any of these persons to comply with these
stipulations shall be deemed a failure of the lessee to comply with the terms of the lease. The lessee shall require his agents, contractors and subcontractors involved in activities concerning this
lease to include these stipulations in the contracts between and among them. These stipulations may be revised or amended, in writing, by the mutual consent of the lessor and the lessee at any time to
adjust to changed conditions or to correct an oversight. 


(a)   CULTURAL RESOURCES -  


(1)
Before undertaking any activities that may disturb the surface of the leased lands, the lessee shall conduct a cultural resource intensive field inventory in a manner specified by the authorized
officer of 


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the
BLM or of the surface managing agency, if different, on portions of the mine plan area and adjacent areas, or exploration plan area, that may be adversely affected by lease-related activities and
which were not previously inventoried at such a level of intensity. The inventory shall be conducted by a qualified professional cultural resource specialist (i.e., archeologist, historian,
historical architect, as appropriate), approved by the authorized officer of the surface managing agency (BLM, if the surface is privately owned), and a report of the inventory and recommendations for
protecting any cultural resources identified shall be submitted to the Assistant Director of the Western Support Center of the Office of Surface Mining, the authorized officer of the BLM, if
activities are associated with coal exploration outside an approved mining permit area (hereinafter called Authorized Officer), and the Authorized Officer of the surface managing agency, if different.
The lessee shall undertake measures, in accordance with instructions from the Assistant Director, or Authorized Officer, to protect cultural resources on the leased lands. The lessee shall not
commence the surface disturbing activities until permission to proceed is given by the Assistant Director or authorized officer. 


(2)
The lessee shall protect all cultural resource properties within the lease area from lease-related activities until the cultural resource mitigation measures can be implemented as part of an
approved mining and reclamation or exploration plan. 


(3)
The cost of conducting the inventory, preparing reports, and carrying our mitigation measures shall be borne by the lessee. 



(4)
If cultural resources are discovered during operations under this lease, the lessee shall immediately bring them to the attention of the Assistant Director or Authorized Officer, or the Authorized
Officer of the surface managing agency, if the Assistant Director is not available. The lessee shall not disturb such resources except as may be subsequently authorized by the Assistant Director or
Authorized Officer. 


Within
two (2) working days of notification, the Assistant Director or Authorized Officer will examine or have evaluated any cultural resources discovered and will determine if any action may
be required no protect or preserve such discoveries. The cost of data recovery for cultural resources discovered during lease operations shall be borne by the surface managing agency unless otherwise
specified by the Authorized Officer of the BLM or of the surface managing agency, if different. 


(5)
All cultural resources shall remain under the jurisdiction of the United States until ownership is determined under applicable law. 


(b)
PALEONTOLOGICAL RESOURCES - If paleontological resources, either large and conspicuous, and/or of significant scientific value are discovered
during surface disturbing activities, the find will be reported to the Authorized Officer immediately. Surface disturbing activities will be suspended within 250 feet of said find. An evaluation of
the paleontological discovery will be made by a BLM approved professional paleontologist within five (5) working days, weather permitting, to determine the appropriate action(s) to prevent the
potential loss of any significant paleontological value. Operations within 250 feet of such discovery will not be resumed until written authorization to proceed is issued by the Authorized Officer.
The lessee will bear the cost of any required paleontological appraisals, surface collection of fossils, or salvage of any large conspicuous fossils of significant scientific interest discovered
during the operations. 


(c)
MULTIPLE MINERAL DEVELOPMENT - Operations will not be approved which, in the opinion of the Authorized Officer, would unreasonably interfere
with the orderly development and/or production from a valid existing mineral lease issued prior to this one for the same lands. 


(d)
OIL AND GAS/COAL RESOURCES - The BLM realizes that coal mining operations conducted on Federal coal leases issued within producing oil and
gas fields may interfere with the economic recovery of oil and gas just as Federal oil and gas leases issued in a Federal coal lease area may inhibit coal recovery. BLM retains the authority to alter
and/or modify the resource recovery and protection plans 


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for
coal operations and/or oil and gas operations on those lands covered by Federal mineral leases so as to obtain maximum resource recovery. 


(e)
RESOURCE RECOVERY AND PROTECTION - Notwithstanding the approval of a resource recovery and protection plan (R2P2) by the BLM, lessor reserves
the right to seek damages against the operator/lessee in the event (i) the operator/lessee fails to achieve maximum economic recovery (MER) [as defined at 43 CFR
3480.0-5(21)] of the recoverable coal reserves or (ii) the operator/lessee is determined to have caused a wasting of recoverable coal reserves. Damages shall be measured on the
basis of the royalty that would have been payable on the wasted or unrecovered coal. 


The
parties recognize that under an approval R2P2, conditions may require a modification by the operator/lessee of that plan. In the event a coalbed or portion thereof is not to be mined or is
rendered unmineable by the operation, the operator/lessee shall submit appropriate justification to obtain approval by the authorized officer (AO) to leave such reserves unmined. Upon approval by the
AO, such coal beds or portions thereof shall not be subject to damages as described above. Further, nothing in this section shall prevent the operator/lessee from exercising its right to relinquish
all or portion of the lease as authorized by statute and regulation. 


In
the event the AO determines that the R2P2 as approved, will not attain MER as the result of changed conditions, the AO will give proper notice to the operator/lessee as required under applicable
regulations. The AO will order a modification if necessary, identifying additional reserves to be mined in order to attain MER. Upon a final administrative or judicial ruling upholding such an ordered
modification, any reserves left unmined (wasted) under that plan will be subject to damages as described in the first paragraph under this section. 



Subject
to the right to appeal hereinafter set forth, payment of the value of the royalty on such unmined recoverable coal reserves shall become due and payable upon determination by the AO that the
coal reserves have been rendered unmineable or at such time that the operator/lessee has demonstrated an unwillingness to extract the coal. 


The
BLM may enforce this provision either by issuing a written decision requiring payment of the MMS demand for such royalties, or by issuing a notice of noncompliance. A decision or notice of
noncompliance issued by the lessor that payment is due under this stipulation is appealable as allowed by law. 


(f)
PUBLIC LAND SURVEY PROTECTION - The lessee will protect all survey monuments, witness corners, reference monuments, and bearing trees against
destruction, obliteration, or damages during operations on the lease areas. If any monuments, corners or accessories are destroyed, obliterated, or damaged by this operation, the lessee will hire an
appropriate county surveyor or registered land surveyor to reestablish or restore the monuments, corners, or accessories at the same location, using surveying procedures in accordance with the
"Manual of Surveying Instructions for the Survey of the Public Lands of the United States." The Survey will be recorded in the appropriate county
records, with a copy sent to the Authorized Officer. 


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Exhibit 10.6