Amendment No. 1 to Master Lease and Sublease Agreement

Exhibit 10.13

Amendment No. 1 to Master Lease and Sublease Agreement

     This Amendment No. 1 to Master Lease and Sublease Agreement (this “Amendment”), effective as of December 30, 2005, is by and between Ark Land Company, a Delaware corporation (“Ark Land”), Ark Land LT, Inc., a Delaware corporation (together with Ark, the “Land Companies”), Thunder Basin Coal Company, L.L.C., a Delaware limited liability company (“TBCC”), and Triton Coal Company, LLC, a Delaware limited liability company (“Triton” and, together with TBCC, the “Operating Companies”).

Recitals

     A. The Land Companies and the Operating Companies are party to that certain Master Lease and Sublease Agreement, dated effective as of April 1, 2005 (the “Master Lease”).

     B. Pursuant to a School Creek Master Agreement, dated as of December 30, 2005, between West Roundup Resources, Inc., a Delaware corporation (“WRRI”), TBCC, Ark Land, Triton and Western Energy Resources, Inc., a Delaware corporation, WRRI and Ark Land agreed to exchange certain coal reserves specified therein.

     C. The Land Companies and the Operating Companies desire to amend the Master Lease to reflect the reserve exchange referenced above.

Agreements

     NOW, THEREFORE, for and in consideration of the mutual covenants contained herein, and other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, the parties agree as follows:

     1. Schedule A and Exhibit A to the Master Lease are hereby deleted in their entirety and replaced with Schedule A and Exhibit A hereto, respectively.

     2. The parties hereby ratify, adopt and confirm the Master Lease as amended hereby and acknowledge that the Master Lease is valid and in full force and effect.

     3. Except as expressly provided herein, this Amendment shall not, nor shall it be construed to, amend, modify or waive any provision of the Master Lease.

     4. This Amendment may be executed in one or more counterparts, each of which shall be deemed an original and all of which together shall constitute one amendment.

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed effective as of the date first set forth above.

Land Companies:				Ark Land Company
				By:		/s/ ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
						▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
						Vice President
				Ark Land LT, Inc.
				By:		/s/ ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
						▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
						Vice President
Operating Companies:				Thunder Basin Coal Company, L.L.C
				By:		/s/ ▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇
						▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇
						President and General Manager
				Triton Coal Company, LLC
				By:		/s/ ▇▇▇▇ ▇. ▇▇▇▇
						▇▇▇▇ ▇. ▇▇▇▇
						President

SCHEDULE A
TO
1ST AMENDMENT TO MASTER AGREEMENT

Coal Leases

Part 1: Thundercloud Reserves

Property

Base

Control

Lessor

Lease

No.

Date

Base Lessor

Original Lessee

Current Lessee

Lease Lands

Royalty

Federal Coal Lease

BT-120

1/1/99

United States

Ark Land Company

Ark Land

T43N, R70W, 6th PM

12.5

%

WYW-136458

of America

Company

Section 4:

W/2 of Lots 8,

9, 16 and 17;

Section 5:

Lots 5-20;

Section 6:

Lots 8-23;

Section 7:

▇▇▇▇ ▇-▇, ▇/▇ ▇▇ ▇▇▇ ▇, ▇▇▇▇ ▇-▇▇, ▇/▇ and SE/4 of ▇▇▇ ▇▇, ▇▇/▇ ▇▇ ▇▇▇ ▇▇;

Section 8:

Lots 1-16;

Section 9:

W/2 of ▇▇▇▇ ▇, ▇ ▇▇▇ ▇▇, ▇▇▇▇ ▇▇-▇▇.

▇▇▇▇, ▇▇▇▇, ▇▇▇ PM

Section 1:

▇▇▇▇ ▇-▇▇, ▇/▇ ▇▇ ▇▇▇ ▇▇, ▇▇▇▇ ▇▇-▇▇, ▇▇/▇▇▇/▇;

Section 12:

▇▇▇▇ ▇, ▇▇/▇ ▇▇ ▇▇▇ ▇.

▇-▇

Part 1: Thundercloud Reserves

Property

Base

Control

Lessor

Lease

No.

Date

Base Lessor

Original Lessee

Current Lessee

Lease Lands

Royalty

Federal Coal Lease WYW-149156

BT-133

▇▇▇▇▇▇ Land & Livestock Company (Sublessor)

Ark Land Company (Sublessee)

T43N, R70W, 6th PM That part of the east half of lots 8, 9, 16 and 17 of Section 4, which is west of a line running north-south along Wyoming ▇▇▇▇▇ ▇▇▇▇▇ (▇▇▇▇ ▇▇▇▇, ▇▇▇ ▇▇▇▇) coordinate E470, 536.83, with an area of 15.07 acres more or less, and;

12.5

%

Federal Coal Lease WYW-148123

BT-133

▇▇▇▇▇▇ Ranch Coal Company (Sublessor)

Ark Land Company (Sublessee)

That part of the east half of lots 4, 5 & 12 of Section 9, which is west of a line running north-south along Wyoming ▇▇▇▇▇ ▇▇▇▇▇ (▇▇▇▇ ▇▇▇▇, ▇▇▇ ▇▇▇▇) coordinate E470, 536. 83, with an area of 14.14 acres more or less.

12.5

%

A-2

Part 2: Little Thunder Creek Reserves

Property

Base

Control

Lessor

Lease

No.

Date

Base Lessor

Original Lessee

Current Lessee

Lease Lands

Royalty

Federal Coal

BT-270

3/1/05

United States

Ark Land LT,

Ark Land LT,

T44N, R71W, 6 th PM

12.5

%

Lease

of America

Inc.

Inc.

Section 35:

Lots ▇-▇▇

▇▇▇-

▇▇▇▇, ▇▇▇▇, ▇▇▇ PM

150318

Section 1:

S/2 of Lot 16;

Section 2:

Lots 5-20;

Section 11:

Lots 1-16;

Section 12:

W/2 and SE/4

of ▇▇▇ ▇, ▇▇▇▇ ▇-▇▇;

Section 13:

Lots 1-16;

Section 14:

NW/4NW/4,

Lots 1-15;

Section 24:

Lots 1-16;

Section 25:

Lots 1-16.

A-3

Part 3: Triton Reserves

Property

Base

Control

Lessor

Lease

No.

Date

Base Lessor

Original Lessee

Current Lessee

Lease Lands

Royalty

Federal Coal

BT-248

▇▇/▇/▇▇

▇▇▇▇▇▇ ▇▇▇▇▇▇ ▇▇

▇▇▇ ▇▇▇▇

▇▇▇▇, ▇▇▇▇,▇▇▇ PM

12.5%

Lease W-71692

America

Company

Section 2:

Lots 17, 18;

Section 3:

Lots 17-20;

Section 10:

Lots 1-4; 6-9;

Section 11:

Lots 1-4, and 8;

Section 14:

▇▇▇▇ ▇,▇,▇,▇,

▇▇▇ ▇,

▇▇▇▇▇▇▇ ▇▇▇▇

▇▇-▇▇▇

▇/▇/▇▇

▇▇▇▇▇▇ ▇▇▇▇▇▇ of

Triton Coal

Ark Land

T42N, R70W, 6th PM

12.5%

Lease WYW-127221

America

Company, LLC

Company

Section 4:

Lots 5-16, 19 and 20;

Section 5:

Lots 5-16.

Section 32:

Lots 9-16;

Section 33:

Lots 11-14

Fee Coal Leases

BT-250-1,

Counterpart

▇▇▇▇▇▇▇ ▇. ▇▇▇▇ et

▇▇▇▇▇▇▇ Coal

Ark Land

T42N, R70W, 6thPM

2,3,4

Leases

ux; ▇▇▇▇▇▇▇ ▇.

Company

Company

Section 11:

W/2NE/4.

(▇▇▇▇▇▇▇ -

▇▇▇▇, ▇▇▇▇▇▇ ▇.

12/20/79)

Reno, Jr. et ux, and

(Dorthy, Burton and ▇▇▇▇▇ 12/27/79)

A-4

SCHEDULE B
TO
1ST AMENDMENT TO MASTER AGREEMENT

Surface Lands

Owner		Property Control ▇▇.		▇▇▇▇▇
▇▇▇ ▇▇▇▇		▇▇-▇▇▇		▇▇▇▇, ▇▇▇▇, ▇▇▇ PM
Company				Section 2:		E/2, LESS and EXCEPTING THEREFROM the railroad right of
						way (See Deed recorded in Book ▇▇▇/▇▇▇▇ ▇▇▇, ▇▇▇▇▇▇▇▇
						▇▇▇▇▇▇, ▇▇▇▇▇▇▇):
				Section 14:		W/2, LESS and EXCEPTING THEREFROM the railroad right of way (See Deed recorded in Book ▇▇▇/▇▇▇▇ ▇▇▇, ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇, ▇▇▇▇▇▇▇);
				Section 15:		E/2.
				T44N, R71W, 6th PM
				Section 25:		SW/4.
				Section 35:		All, LESS and EXCEPTING THEREFROM the railroad
						right of way (See Deed recorded in Book 370/Page 381,
						▇▇▇▇▇▇▇▇ County, Wyoming).
Ark Land		BT-187		T43N, R71W, 6th PM
Company				Section 11:		▇▇▇▇ ▇, ▇, ▇, ▇, ▇, ▇▇, ▇▇ & ▇▇ (▇▇▇ E/2).
Ark Land		BT-143		T43N, R71W, 6th PM
Company				Section 1:		▇▇▇▇ ▇, ▇, ▇, ▇, ▇, ▇▇, ▇▇, ▇▇/▇▇▇/▇, ▇▇▇▇ ▇▇, ▇▇, ▇▇,
						▇▇ (▇▇▇ ▇/▇, ▇▇/▇), LESS and EXCEPTING THEREFROM the
						railroad right of way (See Deed recorded in Book
						▇▇▇/▇▇▇▇ ▇▇▇, ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇, ▇▇▇▇▇▇▇);
				Section 12:		▇▇▇▇ ▇, ▇, ▇, ▇ (▇▇▇ ▇▇/▇), ▇▇▇▇ and EXCEPTING THEREFROM the railroad right of way (See Deed recorded in Book 370/Page 396, ▇▇▇▇▇▇▇▇ County, Wyoming).
Ark Land		BT-271		T43N, R71W, 6th PM
Company				Section 3:		ALL;
				Section 10:		W/2;
Ark Land		BT-271		T44N, R71W, 6th PM
Company				Section 34:		▇▇▇ ▇, ▇▇, ▇▇ ▇▇▇ ▇▇ (▇▇▇ ▇▇/▇)

▇-▇

SCHEDULE C
TO
1ST AMENDMENT TO MASTER AGREEMENT

Prior Lease Agreements

Property

Agreement

Control No.

Date

Lessor

Lessee

Lands

Amended and Restated

BT-121-1

1/18/02

▇▇▇▇ ▇▇▇▇▇▇▇

▇▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇

▇▇▇▇, ▇▇▇▇, ▇▇▇ PM

Lease and Sublease

Resources, LLC

Company, L.L.C.

Section 36: All.

(State Lease)

Amended and Restated Lease and Sublease

BT-121

1/18/02

Ark Land Company

Thunder Basin Coal Company, L.L.C.

WYW-136458

(Federal Leases)

T43N, R70W, 6th PM

Section 4:

W/2 of Lots 8, 9, 16 and 17;

Section 5:

Lots 5-20;

Section 6:

Lots 8-23;

Section 7:

▇▇▇▇ ▇-▇, ▇/▇ ▇▇ ▇▇▇ ▇, ▇▇▇▇ ▇-▇▇, ▇/▇ and SE/4 of ▇▇▇ ▇▇, ▇▇/▇ ▇▇ ▇▇▇ ▇▇;

Section 8:

Lots 1-16;

Section 9:

W/2 of ▇▇▇▇ ▇, ▇ ▇▇▇ ▇▇, ▇▇▇▇ ▇▇-▇▇.

▇▇▇▇, ▇▇▇▇, ▇▇▇ PM

Section 1:

▇▇▇▇ ▇-▇▇, ▇/▇ ▇▇ ▇▇▇ ▇▇, ▇▇▇▇ ▇▇-▇▇, ▇▇/▇▇▇/▇;

Section 12:

Lots 1, NE/4 of Lot 2.

WYW-148123

T43N, R70W, 6th PM

That part of the east half of lots

C-1

Property

Agreement

Control No.

Date

Lessor

Lessee

Lands

8, 9, 16 and 17 of Section 4, which is west of a line running north-south along Wyoming ▇▇▇▇▇ ▇▇▇▇▇ (▇▇▇▇ ▇▇▇▇, ▇▇▇ ▇▇▇▇) coordinate E470, 536.83, with an area of 15.07 acres more or less, and;

That part of the east half of lots 4, 5 & 12 of Section 9, which is west of a line running north- south along Wyoming ▇▇▇▇▇ ▇▇▇▇▇ (▇▇▇▇ ▇▇▇▇, ▇▇▇ ▇▇▇▇) coordinate E470, 536.83, with an area of 14.14 acres more or less.

Sublease

BT-268

8/20/03, as amended

Ark Land Company

Thunder Basin Coal Company, L.L.C. and Triton Coal Company, LLC

W-71692

T42N, R70W, 6th PM

Section 2:

Lots 17, 18;

Section 3:

Lots 17-20;

Section 9:

Lots 9, 10, 15, 16;

Section 10:

Lots 1-16;

Section 11:

▇▇▇▇ ▇-▇, ▇, ▇, ▇▇/▇ of Lot 10;

Section 14:

Lots 1-8;

Section 15:

Lots 1-8.

WYW-127221

T42N, R70W, 6th PM

Section4:

Lots 5-16, 19 and 20;

Section 5:

▇▇▇▇ ▇-▇▇.

▇▇▇▇, ▇▇▇▇, ▇▇▇ PM

Section 32:

Lots 9-16;

Section 33:

▇▇▇▇ ▇▇-▇▇.

▇▇▇▇

▇▇▇▇, ▇▇▇▇, ▇▇▇ PM

Section 11:

W/2NE/4

C-2