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Ms. Jean Olson - 2 - June 1, 1989 If you are in disagreement with the Board's decision whether or not to uphold our decision then you may appeal the Board's decision to your local county District Court. As you can see, there will be numerous opportunities for you to provide input concerning potential impacts to your water rights. Hypothetically, damage to your well could result from blasting impacts to either the aquifer or the well casing or from migration of salty water from the backfilled spoil. The following paragraphs address each of these three potential impacts. Ms. Begej believes that the likelihood of blasting damage to the aquifer supplying your well would be minimal due to the distance between your home and the mine pit (6800') and the strong likelihood that the aquifer supplying water would be far below the Wadge coal to be mined. At this time, her preliminary evaluation of the documentation suggests that the top of the Wadge coal (the lowest seam which Peabody plans to mine at Seneca II W) could be between 6770' and 7200' in elevation, while your home is roughly at 6790'. The bottom of your well would therefore be located at 6140' by these calculations. Ms. Begej will visit you in June to inspect the well documentation you have to determine the elevation of the source of water. Once we have received additional information concerning the specific formation in which your well is completed, we will re-evaluate this potential for impact. We believe the probability of damage to your well casing by blasting to be very small as well. We regulate the potential for blasting damage through standards set in Rule 4.08 on distance, noise, flyrock dispersal and peak particle velocity. Peak particle velocity is a measure of vibration and is limited by Rule 4.08.4(10) to less than one inch-per-second at any dwelling near the mine site. This limitation has been found to provide adequate protection for most man-made structures. The Division checks the blasting records on a regular basis to confirm that blasts are being conducted in accordance with Rule 4.08. You have the right to request that the Division require Peabody to perform a pre-blast survey of your dwelling and the well in accordance with Rule 4.08.2. Your home is located roughly 900' from the northern end of the permit area where the haul road intersects the county road, which is within the one-half mile zone stipulated in Rule 4.08.2(1). This survey would determine the pre-blast condition of the well and the quantity and quality of the water. A report of the survey would be submitted to the Division and a copy would be provided to you for comment. I have enclosed a copy of Rule 4.08.2 for your use. The probability of quality diminution from the migration of salty water from the reclaimed pits is so low that we believe there is no cause for concern. Between 1985 and 1988 the Colorado Mined Land Reclamation Division commissioned Mr. Stan Robson of the United States Geological Survey (USGS) to evaluate projections of bedrock migration in Twentymile Park. This study found that the Wadge and surrounding formations were so impermeable that water moved only 1-30 feet per year.