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Memo to Joe Dudash Bowie #2 Waste Pile Inspection page 3 specification to analyzing coarse materials. If the amended waste material contains a significant fraction as larger than #4 sieve size, one of the material replacement methods must be used to complete the analysis. If incorrectly applied, selection of the wrong analytical method will also bias the proctor test results. 3. Possible inadequacy ojstock piled subsoil volume. - No response has been made to your concern regarding the diversion of subsoil resources from reclamation to waste material amendment. 4. Inadequacy of compaction [esting throughout the initial 20 foot vertical interval of [he +vaste pile. - I shaze your concem in this regard. The initial toe portion of a valley side slope waste pile is extremely important. It becomes the toe buttress for the entire structure. If it develops any strength problems later on it will impact the entire sttucture. Further, material placement and compaction methodology for any earthen structure is commonly developed and perfected during the initial stages of construction. The engineer is not in attendance through the vast majority of the construction. Preferably, however, the equipment operators can benefit from more intense interaction with the certifying technical specialists during the first phase of construction. Various compactive techniques can be tested and verified in order to perfect the methodology to be applied. This interaction also benefits the certifying professional. The inspecting engineer is certifying the competence of the waste pile, based largely upon his surface observations, performed during a very small portion of the structure's life. Personal observations of the methodology and personnel involved in the structure's construction can be an important component of his certification exercise No response has been presented by the operator or its consultant to your expressed concern regarding the apparent paucity of information with which to verify the important initial toe construction of the waste pile at Bowie #2. If no satisfactory information is forthcoming, it may be necessary to disturb the structure in order to complete appropriate verification of waste material constituency and relative density. 5. Verifica[ion ofspecifiedgradation ofthe underdrain materials. - In response to your request for verification of the underdrain material gradation, the operator's consultant has forwarded a reply memo from the supplier stating that the material was supplied in accordance with the specifications. This opinion should be verified through the submission of appropriate gradation analysis testing results. In my opinion the operator has failed to respond adequately to the majority of your requests for verification information regarding [he construction of the waste pile at the Bowie #2 mine.