Matrix Design Group, LLC: Matrix Carbon Monoxide Sensor Passes Advanced Performance Testing, Receives NRTL Listing, and Becomes First Stationary MSHA-Performance-Tested Sensor on the Market

Matrix Design Group, LLC (Matrix), a subsidiary of Alliance Resource Partners, L.P. (NASDAQ: ARLP), announced today that the Matrix WAMS-S1000 Permissible Wireless Carbon Monoxide (CO) Monitoring Sensor has been listed by Intertek, a Nationally Recognized Testing Laboratory (NRTL). With this listing, the WAMS-S1000 fully complies with 30 CFR 75.351 set forth by the Mine Safety and Health Administration (MSHA) and is the only post-accident, performance-tested, and NRTL-Listed CO sensor on the market today.

"We are proud to deliver the first and only CO sensor compliant with the performance-testing standards set forth by MSHA,” said Aric Pryor, President of Matrix. "This accomplishment demonstrates our leadership in cutting edge development of safety technology for the mining industry.”

As part of the performance testing required by MSHA for new CO sensors, the sensor must pass rigorous tests to prove accurate performance and resistance to Radio Frequency Interference (RFI). CO sensors often experience problems with RFI when used in close proximity to two-way radios. Unlike other sensors, the S1000 was specifically designed for resistance to RFI even in close proximity to two-way radios. The S1000’s resistance to RFI was confirmed by performance testing, which established that the sensor is fully compliant with 30 CFR 75.351 and APOL 2207, with no MSHA blasting clearance requirement.

The WAMS S1000 Sensor previously received MSHA Intrinsic Safety (IS) approval (no. 18-A090002-0), allowing the sensor to remain in continuous operation post-accident or during fan outages.

"At Warrior, safety has always been a top priority. We currently have approximately 110 Matrix S1000 wireless sensors underground,” said Eric Anderson, General Manager of Warrior Coal, LLC, a subsidiary of ARLP. "Installing, calibrating, and relocating these new wireless CO sensors has saved our men significant time. We are excited to have a compliant CO sensor that can accurately monitor air conditions underground after the fan is shut off or during other mine emergencies that require the power to be turned off.”

The S1000 CO sensor is part of Matrix’s Wireless Atmospheric Monitoring System (WAMS), which integrates with Matrix’s Miner and Equipment Tracking System (METS) to provide a single underground infrastructure for atmospheric monitoring, communication, and tracking. Currently, there are over 1,000 S1000 units being utilized in US coal mines. For more information, please visit www.matrixdginc.com or contact Matrix at 812-490-1525.

About Matrix Design Group, LLC

Matrix is a designer, developer and marketer of safety and productivity technology for use in the underground mining industry. The innovative and industry leading products of Matrix include communications and tracking systems, mine atmospheric monitoring systems, belt control, and proximity detection systems. Matrix is a subsidiary of ARLP.

About Alliance Resource Partners, LP

ARLP is a diversified producer and marketer of steam coal to major United States utilities and industrial users. ARLP, the nation's first publicly traded master limited partnership involved in the production and marketing of coal, is currently the fourth largest coal producer in the eastern United States with operations in all major eastern coalfields. ARLP currently operates nine underground mining complexes in Illinois, Indiana, Kentucky, Maryland and West Virginia and is also constructing a new underground mining complex in West Virginia. In addition, ARLP operates a coal loading terminal on the Ohio River at Mount Vernon, Indiana.

News, unit prices and additional information about ARLP, including filings with the Securities and Exchange Commission, are available at http://www.arlp.com. For more information, contact the investor relations department of ARLP at 918-295-7674 or via e-mail at investorrelations@arlp.com.