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• (Page 2) • MINE ID # OR PROSPECTING ID # M-86-109 INSPECTION DATE 11-16-98 INSPECTOR'S INITIALS ACS On November 12, 1998, B & B Excavating notified the Division of Minerals and Geology that two or three 55-gallon drums of herbicide had been emptied onto a crushed gravel stockpile at the Montgomery PiC. This inspection was conducted to gather information on this incident, and to develop a corrective action plan to assess and address any potential adverse environmental impacts. Initially, a meeting was held at the B & B office in Edwards. Representing B & B at the Meeting and at the subsequent site inspection were Scott Hoover, B & B's General Manager, Peter Rudy, General Counsel, and Chris Thorne and Paul Phillips, attorneys with the firm of Holland and Hart. Information on the herbicide in question was distributed, including the Material Safety Data Sheet. The herbicide dumped onto the gravel pile is believed by B & B to have been REPCO KILL II manufactured by Amrep, Inc., Cartersville, Georgia. Repro Kill II is a soil sterilant of 2 percent 2,9-D and 2 percent Bromacil in a petroleum distillate base. 2,4-D breaks down relatively quickly in water and has low soil persistence. However, 2,4-D has been detected in ground and surface water throughout the United States, and the Colorado Water Quality Control Commission has established a ground water standard of 70 micrograms per liter. 2,A-D does not bioaccumulate, and is slightly toxic to wildfowl and slightly to moderately toxic to birds. Some formulations of 2,4-D are highly toxic to fish while others are less so. Bromacil is a persistent and highly mobile herbicide. It binds, or adsorbs, only slightly to soil particles, does not readily volatilize, nor does it break down in sunlight. Bromacil can be expected to leach quite readily through the soil and contaminate ground water. Bromacil is practically nontoxic to birds, slightly to practically nontoxic to fish, and nontoxic to aquatic invertebrates. No ground water standard has been established for bromacil, but EPA has established a lifetime health advisory level at 90 micrograms per liter. A written chronology of events was distributed and discussed at the meeting. A description and summary of events, as the Division understands them, is provided here. Currently, the crusher is located on the west side of the Montgomery Pit permit area, and the hot plant is located to the east. '/. inch minus crushed gravel is hauled from the crusher to a stockpile area just north of the asphalt plant where it is screened into ',5 inch minus road base to feed the plant and '/. inch rock. In July 1998, two or three drums of Repro Kill II, which was past its expiration date, were reportedly emptied into the top of the y. inch minus crushed gravel stockpile. The contaminated gravel was then screened to make ',5 inch road base, which remained in a stockpile until November 6, 1998. On November 6, 1998, B and B asphalt crew workers reported weed killer smell coming from the asphalt. On November 7, 1998, the asphalt plant was shut down and the stockpile suspected to contain the herbicide was cordoned off with caution tape. Notifications were made to the national Response Center, the Colorado emergency response center, and Eagle County. On November 9, 1998, the consulting firm of Dames and Moore was engaged to complete an environmental and health evaluation of the incident. Dames and Moore personnel were on-site November 11 and 12, 1998 and collected characterization samples on November 12, 1998. On November 12, 1998, silt fence was installed to further barricade the potentially contaminated stockpile. B and B reports that their air emission permit for the hot plant allows oil stained soils resulting from incidental spills to be run through the plant for disposal. Apparently, a worker or workers at the Montgomery Pit decided that it would be acceptable to dump the herbicide onto the hot plant feed gravel since the herbicide carrier is #2 diesel, so running diesel soaked gravel into the plant would be similar to running oil stained soil. Obviously, to the extent possible all petroleum products must be contained in drums or tanks and all spills cleaned up when they occur. The faulty logic that led to application of 2 or 3 drums of herbicide in diesel fuel to a gravel pile on a potentially pervious substrate adjacent to the Eagle River indicates that there must be additional environmental training of B and B employees. This issue is discussed further below. A t~che request of the Division, B and B provided copies of the Montgomery Pit Storm Water Management Plan and Spill Prevention Control and Countermeasure Plan. An inspection of the Montgomery Pit was conducted, and the following observations were made: