An inventory and assessment of the Carissa Gold Mine property was conducted that included a detailed review of existing environmental investigation and historical documents pertaining to the environmental impact that the Carissa Gold Mine and Mill has had in the past. Also, an overview of surface owners and lessees; mineral owners, mineral lessees and claimants; determination of drilling permitees and site eligibility was made. In addition, geomorphology and localized hydrology, mining, structural and environmental engineering, geology, soils and vegetation, and limited on-site GPS surveying and mapping of the features were conducted.

Land Management's (BLM) General Land Office Records. In general, the date of the title transfer of public A review of land patents was conducted using available files listed within the United States Bureau of land to private ownership can indicate the general time period of the mine operation. Typically, public land is patented after 10 years of continuous occupation and development by a private entity. There are 17 individual patented lode-mining claims of interest associated with the Carissa Gold Mine property. Seven (7) mineral surveys were conducted in determining the various patent boundaries. Research revealed that no active, inactive or terminated mine permits exist or are listed for the lands included within this project. This information indicates that all large-scale mining activities within the project area ceased operation prior to 1973 making them eligible for reclamation under Title IV of the Surface Mining Control and Reclamation Act of 1977.

PHC-REC and AML carried out a thorough review of all existing environmental information available for the Carissa Gold Mine property in an effort to more completely assess the site and to streamline the field investigation phase of the project. Information was obtained from the Carissa Mining Company, AML, Wyoming Game and Fish Department, Wyoming DEQ/Water Quality Division (WQD), Wyoming DEQ/Land Quality Division, Wyoming DEQ/Solid and Hazardous Waste Division, Wyoming Department of State Parks & Cultural Resources (State Parks), and the BLM.

This review indicated that existing environmental data for the Carissa Gold Mine property are fairly extensive in nature, have been collected over an extended period of time, and offer several observations and conclusions to the environmental condition on this property.

Soil, tailings, and sediment sampling have shown that the historic Carissa Mill tailings contain several heavy metals and compounds as a result of not only the milling process, but also the geochemical composition of the ore processed. Arsenic has repeatedly been found to be the primary constituent of concern in the soils and tailings. The Carissa Tailings Disposal Project (AML Project 9B) was carried out to minimize human health and environmental hazards from this finely ground tailings material.

Sediment in the Willow Creek riparian area, adjacent to the Carissa Gold Mine property has been shown to contain elevated levels of total mercury. Mercury has not been shown to be a constituent of concern in the groundwater on the Carissa Gold Mine property.

Information from the WQD indicates that none of the waters within the Carissa Gold Mine property are listed as Impaired or Threatened to become Impaired. There are no data that indicate that the Carissa Gold Mine property is causing impairment to Willow Creek or any other surface water in the area.

The groundwater in the immediate vicinity of the Carissa Mill tailings disposal area does have total arsenic concentrations that exceed the human health drinking water standard. The drinking water well at South Pass City State Historical Site has not shown any metals contamination.

The mitigation of hazards at the Carissa Gold Mine property to acceptable levels of public safety can be accomplished without adverse impact to the environment and will not effect any of the areas of environmental concern described above. There will be environmental improvement as a result of eliminating toxic materials that could become airborne or transported into surface waters by major storm events. The proposed mitigation of high concentrations of heavy metals found in the mill processing waste material, mine ore waste and tanks can be done cost effectively resulting in safe access for the public.

Surface investigations were conducted in the field of each feature within the project site to locate, identify the type and the extent of hazards to public safety. Each feature was investigated by key members of the project team related to their areas of expertise.

All features were inventoried, investigated, evaluated, photographed digitally, and video taped. Surveying and mapping was done for identification and relocation of each mine feature. Each feature was documented on Site Inventory Data Forms and assigned a site name specific to the area investigated. Sampling of mine waste dumps and tailings and of waste material in the mill, including wood structures, floors and tanks, was conducted. Samples of these materials were collected and assayed to identify locations, types and concentrations of hazardous materials.

Fourteen (14) distinct areas of disturbance were investigated, the hazards and existing conditions for each area were identified and inventoried, and preliminary costs to remediate all hazards to an acceptable level of public safety were developed. All identified hazards and potential hazards to public safety are described in the ROI. The hazards were grouped into three (3) categories:

Hazardous materials. This group includes outside mine waste dumps and processing waste material inside the mill. Samples of these materials were collected and assayed to identify locations, types and concentrations of hazardous materials.

During the field investigations, PHC-REC noted on the Site Inventory Data Forms the presence or indication of “historic debris and/or structures,” if observed, at a particular inventoried area. A meeting was held with AML and State Parks personnel in South Pass City on August 20, 2003 for the purpose of discussing possible mitigation methods of the hazards to acceptable levels of public safety at the Carissa Gold Mine property. Issues involving cultural resources, threatened/endangered species, wetlands, and migratory birds of high federal interest that have a direct bearing on final reclamation designs were reviewed. In an effort to provide the Governor and state legislature with as accurate a cost estimate as possible, AML and PHC-REC needed an understanding of the State Parks' management philosophy and post-purchase vision for the property. Additionally, this meeting also presented State Parks with information on potential work at the site that would not be included in the mitigation plan because of non-eligibility. The results of that meeting, as well as several subsequent meetings, are discussed in detail in the ROI.

Final mitigation plans will be influenced by several factors including the State Parks' Master Plan, threatened and endangered species surveys (T&E), and cultural resource surveys. In addition, they will be influenced by the availability of financial grants through the AML and the U.S. Department of the Interior, Office of Surface Mining Reclamation and Enforcement (OSM).

Meetings and conversations between the State of Wyoming and the engineer and concurrence will all impacted parties will be a prerequisite to initiating any final design work. State Parks' considerations must be incorporated into the 95 percent designs to eliminate or minimize disturbance to potentially historic features. Based upon their Master Plan and concerns, areas designated as historically significant will not be reclaimed. In addition, special provisions to utilize the Carissa Mill as an interpretive site will be incorporated into the specifications to ensure compliance with the State Parks' Master Plan.

The mitigation plan recommended in the ROI addresses methods to obtain acceptable levels of public safety, stability, effect of the mitigation plan on the environment, and cost. Engineering design criteria will include risk assessment, environmental and structural engineering analysis, surface water impacts, material strength and stability, and site access.

The investigation considered the cost of three (3) mitigation scenarios based on the level of public access to the Carissa Mill Building. The Carissa Mill Building contains significant historic gold ore processing artifacts and high levels of hazardous materials. The scenarios and associated costs include:

Cost estimates include closure of all hazardous mine openings, stabilization and repair of all buildings to prevent further deterioration of historically significant features and to eliminate the potential for collapse, and removal and off-site disposal of hazardous materials. Cost estimates do not include costs of design, administration, or construction management; these will add approximately twenty five percent (25%) to the cost.