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(Page 2) MINE ID # OR PROSPECTING ID #: ~~-~nOp_ SO rt INSPECTION DATE: 02/»/ns INSPECTOR=S INITIALS: -.AJ.bL OBSERVATIONS This inspection was conducted as the result of a citizen's complaint from Toby Espinosa. The inspection was performed by Tony Wpldron of DMG along with Phil Dorenkamp of Las Animas County. The landowner, Andy Castillo, was also present during the inspection. Mr. Espinosa was offered the opportunity to accompany the inspector during this inspection, but chose not to attend. The site is located approximately 12 miles west of Trinidad, Colorado and sits on an alluvial or colluvial terrace on the south side of the Purgatoire River. The county recently converted an existing 1 l Oc operation to a 1 12c by adding 8.84 acres to the existing 9.90 acres for a new total permitted area of 18.74 acres. The new area was down-slope from the existing disturbed area currently occupying an upland position along a small ridgeline. The focus of the complaint is the presence of an old and poorly marked cemetery near the northwest corner of the permit area. The cemetery is situated on a relatively level part of the terrace, approximately 100 feet before the terrace out-slope drops off into the Purgatoire River valley. The entire terrace is underlain by a gravel layer which is the target of the mining operation. During permitting of this site the landowner and the operator entered into an agreement (per Rule 6.4.19) to protect the cemetery by maintaining a setback of 10 feet on the south and west sides, and mining no closer than the existing fence line on the north and east sides. The operator further delineated the boundaries of the cemetery by means of tee-posts and a single strand of barbed wire to prevent any confusion about where the cemetery boundary was located. The closest disturbance allowed is I O feet from the perimeter of the fenced area. The letter from Mr. Espinosa indicated that excavation was occurring within 16 feet of the nearest grave site in the cemetery, however, no map or directions about where these graves are located was conveyed with the letter. Mr. Dorenkamp had apparently received a map earlier from Mr. Espinosa showing the location of two unmarked graves near the northwest corner of the cemetery. As a result of this information coming forth, the county agreed to expand the perimeter of the cemetery by an additional 5 feet in this area and continue to maintain the 10-foot set-back from this newly delineated boundary. In addition, Mr. Costilla further requested that the county add an additional S foot to the previously agreed upon 10 foot buffer for a new set-back of 15 feet from the county marked perimeter of the cemetery. This was verbally agreed to on the site, furthermore, the county indicated that they would mine through the overburden at 3H:1 V until they exposed the gravel deposit at which time they would mine the deposit vertically followed by backfilling at 3H:1 V. As the overburden appeared to be 4-b feet thick in this area, this would move the actual gravel mining another 12 to 18 feet away from the perimeter of the cemetery for a total distance of approximately 30 feet away from the perimeter fence before any gravel extraction takes place. In addition to these additional setbacks, samples of the overburden and gravel deposit were collected where the underlying gravel has been exposed along the east side of the cemetery. These samples will be used to conduct a stability analysis. A general (and conservative) rule of thumb is that protected structures should be at least twice the distance away horizontally as the depth of the excavation. In other words, if the pit were to be excavated 20 feet deep the horizontal distance from the toe of the slope would be 40 feet to prevent slope failure from extending into the protected structure. Although this is only a "rule of thumb" it would be best for the operator to observe it until the full stability analysis is conducted, which will likely allow mining at a closer distance. Based on conversations with the operator, they are not aware of the exact depth to the bottom of the deposit but estimate it to be 10 to 20 feet. Assuming 15 feet, they wauld need to maintain a distance of 30 feet from the nearest structure, which is approximately the distance to the marked perimeter of the cemetery from the projected toe of the excavated slope of the pit. Once the stability analysis is completed it is likely that the horizontal distance will be reduced and the mining depth could, if necessary, be increased. It is suggested that when mining the area around the cemetery the operator should reclaim the area as contemporaneously as possible to minimize the amount of time the highwall will be exposed. Also, once the