2009-09-21_INSPECTION - M1980183

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(Page 2) MINE ID # OR PROSPECTING ID #: M-19Rn-1R3 INSPECTION DATE: 26 Aiig?ist 2009 INSPECTOR'S INITIALS: ngZ OBSERVATIONS This inspection was conducted by David Bird and Tony Waldron of DRMS in response to complaints received from seven members of the Zigan Homeowners Association, an organization of homeowners who live around the lake located southeast of the intersection of 126`h Avenue and Brighton Road in Adams County. The homeowners and the lake are located south of Brannan's Pit 29. The citizen complaints included wet crawl spaces, inundated leach fields and septic tanks, submerged docks and recreational equipment, and washed out beaches. The Division met Greg Gerganoff and Fred Marvel of Brannan Sand & Gravel Company at the Brannan Pit 29 site on 26 August 2009 to explain the situation and discuss options. The citizens reported that they first started noticing elevated ground water and lake levels about four years ago coincident with installation of slurry walls at Brannan's Pit 29 and Lafarge's Stagecoach Pit, now operated by Albert Frei and Sons, Inc. (Frei). DRMS believes that the two slurry walls have created a barrier to ground water flow, which is known to have a gradient in a northwesterly direction in this area. The barrier prevents ground water in the South Platte alluvium from following its natural course to the South Platte River. This causes ground water mounding and elevated water levels at the residences and in the Zigan Lake located hydrologically u pgrad lent. DRMS considers the ground water mounding a problem, and this has been cited on page 4 of this report. Specifically, the ground water mounding problem constitutes a disturbance to the prevailing hydrologic balance of the affected land and of the surrounding area and to the quantity of water in the groundwater systems during mining. If left unabated, it could constitute a violation of § 34-32.5-116(4)(h) C.R.S. of the Colorado Land Reclamation Act for the Extraction of Construction Materials, and Rule 3.1.6(1) of the Mineral Rules and Regulations of the Colorado Mined Land Reclamation Board for the Extraction of Construction Materials. If left unabated, the mounding situation could further escalate to include off-site damage, whereupon the problem would become a violation of § 34-32.5-116(4)(i) C.R.S. and Rule 6.3.3(1) for failure to protect areas outside of the affected land from being damaged during mining or reclamation operations. DRMS believes the solution to the problem must involve a means of relieving the mounding on the upgradient side of the barrier to flow created by the two slurry walls. Toward that end and as a long term solution, Frei and the Zigan homeowners have proposed a ditch draining the Zigan Lake at an elevation designed to prevent the lake from exceeding some maximum level, yet to be determined, with the ultimate goal of preventing excessively high water levels that could adversely impact the residences around the lake. In the interim, Frei has been pumping water from the Zigan Lake and has lowered the lake level sufficiently that the immediate threat of property damage has been alleviated. DRMS is of the opinion that the Stagecoach pit and Pit 29 are equally to blame in the creation of the mounding situation, and therefore DRMS believes that the financial burden of abatement should be shared equally by the two operators. If the ditch proves not to be feasible in the long term for whatever reason, then the Operators must consider alternative means of relieving the mounding situation. The solution for this scenario will likely involve installation of a French drain around at least one of the pits with the financial burden shared by both parties. The long-term abatement plan will require the submittal, review, and approval of either a Technical Revision or an Amendment, depending on the magnitude of the abatement, prior to implementation.