Colorado Stone Quarries Addresses Fuel Spill NEWS RELEASE Media Contact: Lisa Sigler For CSQ 303-778-8355 or 303-916-2257 lisa@siglerinc.com Marble, Colo -- In October 2019, the Pride of America Mine operated by Colorado Stone Quarries, Inc. in Marble, CO, (“CSQ”) had an accidental diesel fuel spill at its quarry site in Marble, Colorado. After discovering fuel had overflowed from a storage tank, CSQ promptly began efforts to clean-up and remediate the spill to prevent the fuel from entering Yule Creek. CSQ uses diesel fuel in electric generators that provide power for the mine. The combination of unrelated mechanical and electrical issues allowed the fuel to breach both the primary and secondary containment of the fuel system. The fuel system leaked fuel into road base material beneath the generator. CSQ retained consultants experienced in responding to fuel leaks at transportation, industrial, oil & gas, and mine sites. CSQ reported the incident to regulatory authorities and worked closely with state and federal regulators to develop an approved clean-up plan to prevent migration of the fuel into Yule Creek and remediate diesel contaminated fill material. Daniele Treves, General Manager of CSQ, notes, “After the spill, we shut down operations and diverted our personnel from quarry activities to clean-up. Colorado Stone Quarries has worked hard to ensure no diesel fuel entered Yule Creek, and we are very pleased those efforts succeeded. We take environmental protection at the mine seriously and we are continuing an internal investigation of what went wrong, and how we can work to prevent it from happening in the future. I am grateful for the quick actions and hard work of CSQ’s employees, consultants and mining officials, and appreciate state and federal regulators’ regular communication with us as we worked to protect the creek and clean up the spill.” The spill was reported in October to the Colorado Division of Reclamation, Mining and Safety (DRMS), the Colorado Department of Public Health and Environment (CDPHE), the Mine Safety and Health Administration (MSHA), and the U.S. Army Corps of Engineers (USACE). Additionally, CSQ submitted a comprehensive incident report to the DRMS describing the cause of the spill, CSQ’s clean-up efforts to date and its ongoing monitoring. “We acknowledge there were several days between when the accident occurred and when it was reported to regulators,” said Treves. “Our focus at the time was minimizing any environmental impacts of the fuel release and taking steps to make sure the fuel did not reach the creek. While our company was successful in its emergency response, we are fully reviewing the reasons for the delay and our environmental processes, including our past and current reporting procedures.” The incident report was prepared by the engineering and environmental consulting firm Greg Lewicki and Associates (“GLA”) and was submitted to Colorado regulators. The following actions were taken and are noted in the report: Cleanup Activities: • • • During the evening on October 11, 2019, a diesel fuel storage tank accidentally overfilled and spilled approximately 5,500 gallons of diesel fuel.1 The primary method of remediating the spilled fuel was excavating oil contaminated road base. The secondary method involved flushing the more deeply buried fill materials impacted by diesel with a large volume of water. Flushed liquid was then collected in the sump pit previously put in place to handle storm water.2 The water was pumped from the sump and taken off-site for safe disposal. This process continued until flushed water in the sump pit demonstrated no presence of diesel fuel.3 CSQ also put in place a long-term water sampling plan to confirm there are no impacts on Yule Creek. The work was approved by DRMS prior to initiation of activities. Sampling and monitoring activities to date demonstrate, “No detectable discharge of contaminated water occurred at any time during the initial spill and through mitigation and the start of remediation.”4 GLA expects no future risk to Yule Creek from the spill.5 Factors that Contributed to the Spill: • • The primary factor that contributed to the spill was a complicated electrical issue that caused the fuel supply system to the generator’s “day” tank to overfill, thus breaching its primary containment. The issue involved an undervoltage condition within the power supply to the fuel system. The power supply issue has been resolved and steps were taken to prevent it from occurring again. The secondary factor contributing to the spill was a tank vent extension that had not been reinstalled on the day generator tank. Typically, when the tank reaches over-capacity, the vent and a separate fuel return pipe fill with fuel and settle at a level that returns excess fuel from the day tank back into a larger storage tank. As a result of earlier work on the fuel supply system, the extension pipe of the vent was removed to perform maintenance activities and inadvertently was not replaced.6 When the tank filled to over-capacity on the evening of October 11, 2019, fuel that otherwise would have risen to a stable level in the vent and fuel return pipes spilled out through a vent cap.7 The vent extension pipe has now been reinstalled. 1 GLA Report at 2. GLA Report at 36. 3 GLA Report at 37. 4 GLA Report at 2. 5 GLA Report at 3. 6 GLA Report at 7-8. 7 GLA Report at 7-8. 2 2 Actions Taken Since Immediate Cleanup Activities: • • • • • • CSQ removed the tanks and generators to clean-up diesel contaminated road base and fill. Prior to replacing the tanks and generator, CSQ installed a HDPE liner to provide tertiary containment in the event of a future spill. A photo of the liner is found at page 39 of the GLA Report. Contaminated fill material was disposed of in a permitted facility, South Canyon Landfill in Glenwood Springs. Contaminated flush water was disposed of in a permitted facility, Green Leaf Environmental Services in De Beque. Bioremediation, a common method used to enhance the natural degradation of hydrocarbons, is being used at the site. Microorganisms and nutrients were added to subsurface and surface of the impacted fill material to accelerate naturally occurring processes that enable the organisms to consume hydrocarbons and clean up the fill material. CSQ’s consultants are conducting ongoing surface and sub-surface water sampling starting above the mine site along Yule Creek downstream to the confluence of Yule Creek and the Crystal River. Additional processes and procedures are being added to the regular training of CSQ staff to improve their handling of and response to spills. About Colorado Stone Quarries The white marble of Yule Creek was discovered in the 1880s and soon became known as one of the finest white marbles in the world with quarry operations beginning in 1874. It was selected for the exterior of the Lincoln Memorial in 1916 and the Tomb of the Unknowns in 1936. It has supplied marble for the Lincoln Memorial in Washington D.C. and the Capitol Building in Denver, Colorado. The quarry closed in 1941 and remained a tourist destination until 1990, when it was re-opened by the new Colorado Yule Marble Company (CYMC). The mine has been operating as the Pride of America Mine since April of 2004. CSQ employs 30-40 individuals from surrounding areas, and the management team is sourced from Italy. Quarrying operations at the site utilize mechanical cutting techniques rather than drilling and blasting. Similar techniques are utilized both underground in the galleries and outside in the quarries. Finished blocks are shipped to the historic mill site for transloading onto highway trucks. When possible, waste marble is put to beneficial use by utilizing blocks for erosion protection and to supply crushed road base. Additional waste marble is used to create stable waste rock landforms to remain in final reclamation. Currently underground galleries include the Lincoln and Historic Washington galleries while surface quarries include the Franklin quarry and the soon-to-be-opened Jefferson Quarry. 3