Appendix A: Rosemont Project Mining Plan of Operations

File Code: 2810
Date: October 19, 2007

For the ground and surface water portions of the MPO, there needs to be a description of the potential for mine dewatering, potential for a post mining pit lake with the geochemical characteristics that could be expected, and a water balance plan describing all water sources and uses, including groundwater withdrawals in the area of the mine site itself. There is sufficient information provided for the west side of the project area for the CAP water, pipeline routes, production wells, etc., but very little groundwater information is included on the mine site itself.

The following specific information is needed concerning water in and around the project area:

• General information on the location of any dewatering wells. This information would probably be based on local geology and what is currently known of the groundwater regime, and locations may change as the project develops.

• A conceptual groundwater model based on current information. This model will be recalibrated regularly, probably annually, for the first few years, and will be utilized for estimating impacts to ground and surface water in the vicinity.

• A conceptual groundwater monitoring plan. There should be at least four or five wells just outside the ultimate pit perimeter before any mine operations begin. Recording of water levels should begin well before any mine operations commence, and the recording interval should be no greater than one week. There should be some wells installed at greater distances for monitoring the growth of the cone of depression, four or five to begin with, and plans for more to monitor the horizontal growth of the drawdown. Both shallow and deep aquifers should be targeted.

• All pertinent information on groundwater wells installed for this project, including drill logs, completion logs, screened interval locations and depths, sample intervals, completion depths, materials used in well development, water flow rates, and water quality data.

• Information on existing groundwater levels, direction of flow, gradient, transmissivity and pump testing.

• Water rights data.

• Vertical characterization of groundwater quality, including characterization of different geologic units at different depths, such as fractures, alluvial subflow, and alluvial aquifers.

• Data on existing stream channels and banks, including profile information, cross sections bankfull discharge, pebble count, width to depth ratio, and sinuosity; this is especially important at the Point of Compliance dam area where the project will outfall to the undisturbed stream.

• Data on existing spring characterization, including location, quantity, flow volumes, and water quality, and information on potential spring upwelling under project features such as the leach pad liner.

• Information on sampling protocols, analytical methods, quality assurance and quality control methods for each type of hydrologic and hydrogeologic data collected.

• Design of retention ponds in the area of the waste rock pile. Currently the MPO calls for a 100 foot horizontal setback from the hydrologic grade break to the base of the toe. It appears that the storm water will percolate back into the waste rock pile; what is the design freeboard prior to overtopping into an adjacent drainage such as Oak Tree Canyon?

The following information is needed in order to clarify questions about land status in the project area, and to improve the readability of maps and diagrams in the MPO and support documents:

• Clarification on what is meant by "controlled by Augusta Resource Corporation" (Executive Summary, page 1, third paragraph).

• Clarification as to the number of unpatented claims there are associated with this project. Paragraph 2 of section 1.2 lists 850 unpatented claims, while Appendix A lists 864. In addition to BLM serial numbers, the list of unpatented claims should include claimant information, township range and section, and type of claim.

• Identification of ownership (private, county, state, and federal) administrative status (proclaimed Forest boundary, Las Cienegas National Conservation Area, Santa Rita Experimental Range, etc), and management (Forest Service, BLM, University of Arizona, State Land Department, etc.) on all project maps and diagrams.

• Section, township and range lines on whatever is being portrayed (ancillary facilities, general site arrangements, geology, etc.) on a map or diagram, regardless of scale (from less than an acre to several townships). Maps should have a connection to on the ground features or references; currently many of the maps use only digital elevation model data which is difficult to relate to real world locations.

• Different colors for each ownership or managerial jurisdiction shown on project maps and diagrams. I suggest utilizing the ownership colors used on Forest Service ½" – 1 mile Forest visitor maps. The proclaimed National Forest Boundary should be portrayed on maps as a bold black line.

• A definition, in common terms, of the phrase "Rosemont Land Position". Does this equate to the area including al unpatented mining claims and private land held by the corporation?

• A map showing the individual unpatented lode mining claims in relationship to the private ownership and National Forest system lands.

• A depiction of project study boundary limits (i.e., project footprint) on all project related maps, regardless of scale.

Other information that is needed with the MPO and supporting documents includes the following:

• The state in which Augusta Resource Corporation was incorporated and the articles of incorporation.

• Identification of staging areas and temporary roads needed for the preproduction phase (Figure 2.2 of the MPO).

• Information relative to hazardous material quantities and their specific storage locations.

• Initial designs for the Waste Rock Facility.

• Details on procedures to be implemented in the event of a temporary shut-down in operations.

• A description of the disposition of existing mine workings.