FIRST MODIFICATION TO LOAN AND SECURITY AGREEMENT

Exhibit 10.15

FIRST MODIFICATION TO

LOAN AND SECURITY AGREEMENT

This First Modification to Loan and Security Agreement (“First Modification Agreement”) is made and entered into this 27th day of August, 2013, by and between BISON DRILLING AND FIELD SERVICES LLC, a Delaware limited liability company (“Borrower”) and INTERNATIONAL BANK OF COMMERCE (the “Lender”).

WITNESSETH:

WHEREAS, on or about May 31, 2013, Borrower and Lender entered into that certain Loan and Security Agreement (the “Loan Agreement”) pursuant to which Borrower executed and delivered to Lender two promissory notes, as follows (1) that certain Revolving Line of Credit Promissory Note in the face amount of $5,000,000, with a maturity date of June 1, 2014 (“Revolving Note”); and (2) that certain Promissory Note in the face amount of $30,000,000, with a maturity date of April 17, 2013 (the “Term Note”) (the Revolving Note and Term Note are collectively referred to as the “Notes”); and

WHEREAS, Borrower and Lender wish to modify certain terms of the Loan Agreement, as provided for herein; and

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

1. Modification of Collateral: Lender and Borrower desire to amend the descriptions of certain Collateral contained on Schedule 1 of the Loan Agreement as follows:

(a) Schedule 1: Schedule 1 of the Loan Agreement is hereby deleted and replaced with Schedule 1 attached hereto.

(b) Modification of UCC Filings: Lender is authorized to correct any UCC filings made in connection with the Loan Agreement to reflect the replacement of Schedule 1 herein.

2. Replacement of Certain Provisions. Each of Section 2.1(b) and Section 6.20 of the Loan Agreement is hereby deleted and replaced with the following respective provisions:

2.1(b). Term Note Use of Proceeds. Lender agrees to lend to Borrower the Term Loan for the specific purpose of: (i) refinancing Borrower’s current term loan with Amegy Bank with a principal balance of approximately $8,750,000; (ii) providing Borrower funds in the amount of approximately $7,500,000 to upgrade and improve a certain drilling rig known as Rig #80; (iii) providing Borrower funds in the amount of approximately $3,250,000 to upgrade and improve Borrower’s ancillary business activities, including running casing, rathole and mousehole drilling, rental items, hot oil (well service) and vacuum trucks (well service); (iv) provide Borrower funds in the amount of approximately $7,500,000 for purchase of certain equipment, including sixteen (16) new Kenworth trucks, ten (10) trailers, two (2) cranes and providing initial working capital for Borrower’s Heavy Hauling Group; (v) providing Borrower

funds in the amount of approximately $3,000,000 for upgrading and relocating two (2) of Borrower’s existing rigs for deployment in the Utica Shale in Ohio; and (vi) to pay Lender the Loan Fee described in Section 2.3 herein and Lender’s other costs of Closing, including but not limited to Lender’s attorney’s fees, filing fees and appraisal costs.

6.20. Fixed Charge Coverage Ratio. Beginning with the quarter-ending March 31, 2014, Borrower will at all times maintain a Fixed Charge Coverage Ratio of not less than 1.25 to 1, calculated and tested quarterly on a rolling 4 quarters basis. The Fixed Charge Coverage Ratio is calculated as the EBITDA for the period minus Distributions, minus Non-Financed Capital Expenditures, divided by the sum of current maturities plus interest expense.

3. Effectiveness of Loan Documents: Except as specifically modified by the terms and provisions hereof, each and every of the terms and provisions of the Loan Documents (as defined in Section 1.29 of the Loan Agreement) are and shall remain in full force and effect and are hereby assumed, ratified, and confirmed; and the execution, delivery, and effectiveness of this First Modification Agreement shall not, except as expressly provided herein, operate as a waiver of any right, power or remedy of Lender under any of the Loan Documents nor constitute a waiver of any provision of any of the Loan Documents. The parties hereto agree that the modifications herein contained to the Loan Documents shall not affect or impair the Loan Documents or any lien(s) securing the same.

4. Execution Counterparts: This First Modification Agreement may be executed in any number of counterparts, each of which so executed and delivered shall be deemed to be an original and all of which taken together shall constitute one and the same instrument.

5. Governing Law: The terms and provisions hereof shall be governed by, construed, and enforced in accordance with the laws of the State of Oklahoma.

6. Entire Agreement: This First Modification Agreement constitutes the entire agreement of the parties with respect to the subject matter hereof, and may be amended only in writing, executed by all parties herein.

7. Modification Only. This agreement is only a modification of the Loan Agreement and not a novation. All terms and conditions of the Notes and all other Loan Documents executed in connection with said Notes shall remain in full force and effect.

8. Defined Terms. Any term not defined herein shall have the meaning set forth in the Loan Agreement.

IN WITNESS WHEREOF, the parties hereto have executed this First Modification Agreement as of the date first above written.

SCHEDULE 1

To Loan and Security Agreement

Equipment Collateral

The Equipment described in Section 1.14( c) of the Loan and Security Agreement includes, but is not limited to:

Capital Equipment

Vehicles

Not in Service Equipment

Draw works: 125 National/Ideal 2000 hp (qty 1) (Ram)

Ingersoll Rand Air Hoist (Kruse)

Gardner Denver Air Hoist (Kruse)

Air Hoist Winch (Yantai)

10’W x 32’L Tool Pusher House (Kruse)

42“H x 4’10”W x 57’L Catwalk w/ Steel Deck (Kruse)

Koomey 6-Station Closing Unit (Kruse)

42“H x 5’W x 50’L Sgl Sec Catwalk (Kruse)

27 1/2” Rotary Table (Kruse)

Rebuilt Rotary Table

Skytop Brewster Drawworks/Deadline Anchor Henderson

Supply

Air Compressors: 185 cfm air compressor Ser. # 11076 (Ram)

Mathey Style Retriever Wireline Machine (kruse)

Torque converters: National C-300 Ser. # 1930 (Ram)

Torque converters: National C-300 Ser. # 1931 (Ram)

Torque Spare (Rebuilt Rig 41) (Rig 62)

3406 w/ Allison Engine (Warren)

Floor Engines (Rig 62 drawworks rebuild)

3408 CAT Diesel Engine

D395 Engine Overhaul

CAT Rebuild (Rig 87 drawworks)

Mud Pump (Gear End)

Pump Motor

Mud Pits - Shale Shaker

Trip Tank (Warren)

Max 2000 10 HP Mud Agitator p/h Elec Mtr. (2) Drk. Vibrators

Shaffer Type B 13 5/8” 3M Dbl w/o Rams

5M# Choke Manifold w/ (1) 3 l/16” (3) 2 l/16” Gates

2002 CAT 435 KW Generator p/b C-16 (3456 hrs)

Genhouse: 3412 cat gensct 525 kw on open wall genhouse Ser·

# 00000klry00572-3f07647 (Ram)

Portable generator: Cummins 180 kw enclosed tandem trailer

Ser. #. rl-19-51838-10/21-1 (Ram)

3406 Generator (Warren)

Electric motors: 75 hp & 40 hp baldor motors (Ram)

7,138 feet of Drill pipe

Drill Collar 5 1/2” to 7” Slips

Type C Drill Collar Safety Clamps (4)

6 5/8” Reg Slick Drill Collars

4 1/2” XH Slick Drill Collars

Pipe Racks: Ass. Pipe racks and steel racks (Ram)

(2) 42“H x 28’L Triangular Pipe Racks

(2) 42“H x 15’L & (2) 42“H x 28’L Triangular Pipe Racks

Set (2) 42“H x 28’L Triangular Pipe Racks (Kruse)

Crown Cluster set of 56’x5” sheave cluster, grooved 1 3/8”

(Ram)

Gardner Denver Traveling Blocks (300 Ton) (From Rig 41)

EMSCO 250 Ton Block

Swivels: Gardner Denver 400 Ton (Ram)

Swivel (Rig 41)

5 1/4” Hex Kelly (38.5’) (Kruse)

5 1/4” Hex Kelly Drive Bushings (Kruse)

Kelly Hoses: 42’x4” gates kelly hoses (Ram)

Kelly Hoses: 20’x4” gates vibrator hoses (Ram)

Kelly Hoses: 10’x4” gates vibrator hoses (Ram)

VARCO 5 1/4” HEX KELLY DRIVE BUSHING

3 1/2” ID Rotary Hose

2 3/4” x 108” Elevator Links (Kruse)

(2) 2 3/4” x 108” Elevator Links (Kruse)

BJ Type B Tongs w/ Heads (Kruse)

WTM Type B Tongs w/ Heads (Kruse)

SDML 3 1/2” to 4 1/2” DRILL PIPE SLIPS W/ Inserts

Flanges: assortment 4”, 6”, 8” (Ram)

Pipe Fittings: assortment of ells forty fives collars/flanges

(Ram)

Ball Valves: 2”, 4”, 6” brass and steel valves (Ram)

Large assortment of nuts, bolts and fittings (Ram)

Sand blaster with hoses and nozzle (Ram)

3 Welders (Warren)

342 Brakes (Warren)

Chemical BBls (Warren)

HPU (Warren)

Pump Expendables (Warren)

MCM cent Pumps (Warren)

(16) Sets of 9“H x 28’L Pipe Runners (Kruse)

5 1/4” Hex Kelly w/ Varco HD Drive Bushing & Shuck (Kruse)

(7) WTM Type A (4) 9 Seg (2) 10-Seg (l) 12 Seg (Kruse)

3 1/2’’ ID x 25’L Steel Flex Hose & 3 1/2“ID x 20’ Vibrator

Hose (Kruse)

(5) Slips (AOT, (2) Varco, Wooley B-long, Wooley 8 Seg)

(Kruse)

(2) Type T DC Safety Clamps (NEW) (Kruse)

(1) 12 Seg, (1) 8 Seg, 7 Seg, 2” Chicksan, (6) Handls, Auto

Drill Sensor (Kruse)

398 Engine Rebuilt (originally from Rig 62)

Mud Pump (>350 HP) Maxium (M-1300)

#2 Generator Engine(Cat D379)

Wilson SD Casing Elevators (Kruse Pittsburgh)

Ancillary Items

MISC Equipment & Supplies

20’ SEA CONTAINER

BLOWOUT PREVENTER 1-1

BLOWOUT PREVENTER 2-1

BLOWOUT PREVENTER 3-1

REPLACEMENT

FLOWBACK TANK 1-1

FLOWBACK TANK 2-1

FLOWBACK TANK 3-1

CLIPPER LINE SCALE

WELDER

CAT WALK

WELDING TOOLS

RAW STEEL

MISC SHOP SUPPLIES

PIPE RACK

3-1/2” SLICK DRILL COLLAR

BJ 50 TON AIR TUBING SLIPS

ELEVATOR LINKS

TUBING ELEVATOR

TUBING AIR SLIPS

ROD ELEVATORS

3 1/8” DRILL COLLARS - 10

3 1/2” DRILL COLLARS- 9

LIFT SUBS- 18

DRILL COLLAR

ACCESSORIES (XOVER)

DRILL COLLARS

TUBING TONGS

PIPE RACKS

SANDLINE

SHAFFER 7 1/16” 3K# BOP

SHAFFER 7 1/16” 3K# BOP (2)

BJ TYPE TBG TONGS