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SNOWCAP COAL COMPANY South Portal Roadside Refuse Disposal Area Inspection - 3'' Quarter 2002 On September 17, 2002, 1 performed the required quarterly visual inspection of the Roadside Refuse Disposal Area in accordance with Rule 4.10.2. I, J. E. Stover, P.E., have a wide variety of experience in the design and construction of earth fill embankments. Nothing was observed during the inspection that would indicate the pile has a potential for failure. The pile was dry. There is an erosional feature that was noted on September 8`". It is located on the face of the second bench of the north facing slope. The erosion feature is unusual because it originates at mid slope. An ahimal burrow was located near the top of the feature and the cover material immediately to the west was stained grey. Investigation of this erosional feature involved hand excavation of the animal burrow approximately 30-feet to the west. The animal burrow stayed in the dry powdery material which indicates it was not the conduit for water flow. At the end of the hand excavation, the animal burrow was about 1-inch in diameter and it tilted at a sharp angle down toward the refuse material. The soil in the area was damp about 6-inches deep. The most unusual discovery was a black veneer coating of the soil horizon exposed immediately above the erosional feature. My theory regarding the cause of the erosional feature is that flow occurred at the interface of the refuse and soil cover. The water surfaced at a weak point, possibly caused by the animal burrow. The water contained fine refuse particles which caused the grey stain and black veneer coating. I do not know the source of the water. There is no indication of significant seepage on the bench above. I believe there is a good chance that subsequent precipitation events will seal off the source of water. The erosional feature was not repaired but left open for further observation. A significant storm event occurred on September 29`". On October 151, I inspected the erosional feature. There was no indication of additional subsurface flow. The contractor competed covering the outslopes of the pile during the previous quarter. The cover material needs to be shaped and slightly roughened. Installation of the upper diversion ditch was completed during the quarter. The design of the upper diversion ditch is located at Volume 5, Appendix 14-6, beginning on page 14-6-1. Segment A of the upper diversion ditch is a trapezoidal channel with a 3-foot wide bottom, 3% grade and 3.32 feet deep with freeboard. There is one section of this as-built ditch segment that has a grade of 1.5% and numerous sections of the ditch that are only 2-feet deep. I