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• (Page 2) • MINE ID # OR PROSPECTING ID # M-77-215 INSPECTION DATE 6-1-98 INSPECTOR'S INITIALS SSS This was a partial inspection conducted to evaluate the area of the 9360 portal seal second monolithic concrete block, prior to pouring the concrete. Pouring of the concrete was also observed. The area inside the concrete forms was inspected approximately 2 hours prior to the concrete injection pumping. Most of the lagging was still in place on the ribs except for in the places where a grout injection pipe was placed. All lagging had been removed from a section of the back between two timber sets. The caved area above this section was approximately six feet above the top of the sets. Spreaders and timbers at the base of the sets, running parallel to the adit were all still in place. This condition is of concern as it may provide a continuous flow path through the concrete block that water could conceivably pass through as the timber degrades. During the 4-8-98 inspection, the Division specified that Homestake would need to remove all lagging and timbers from a section of the adit where the first section of the plug was to be constructed, so there would be a full circumference, concrete to earth contact, with no wood passing through it that may provide a flow path for water to channel through the seal. Homestake was directed to photographically document this wood free zone and submit that documentation to the Division. This documentation has not been submitted as of this inspection. Therefore, the Division has no evidence that there is a full thickness wood free zone in the first section of the portal seal. Homestake indicated, during the Division's 5-13-98 inspection, that all the lagging and timber was not removed from the area between two timber sets which was to be cut out to disrupt any potential continuous flow paths through the seal. Homestake indicated that a section of lagging and other timber, around the entire circumference of the adit, would be cut out of the area for the second concrete block of the seal, and that the second block would be the area where the best seal would be provided because there they would get a full thickness concrete to earth seal, free of any wood. inspection of the area of the second concrete block, two hours prior to pumping the concrete revealed that lagging in the back had been removed between two timber sets and caving had occurred to approximately six feet above the sets. Grout, from the injection around the first plug section, was visible in voids and cracks where the back had caved away. Hardly any lagging had been removed from the ribs except where grout injection pipes had been placed to pump grout around the second section of concrete plug. It appeared that no timbers from the floor, oriented either parallel or perpendicular to the adit, had been removed. A few one inch holes had been drilled through each lagging board to aid grout penetration. Homestake was advised of the Division's concern about the amount of wood remaining in this zone. Homestake indicated that regard for the safety of the miners was the reason for not removing all wood between these sets, Steve Philips of Philips Mining, Geotechnical & Grouting, Inc., indicated, contrary to earlier statements from Homestake personnel, that all wood was removed from a zone between two timber sets in the first section of the plug. Homestake personnel indicated that photographic documentation of that area was taken prior to removal of tall the lagging, so it would not verify Mr. Philips statement. Therefore, Homestake is directed to submit an ae-built report for the adit seal construction, upon completion of the structure. Other than the lack of timber removal, the area of the second plug section was clean, loose debris had been removed and the face of the first plug section had been scoured to provide