Impacts from surface-disturbing activities, resource uses, and proactive management actions may result in adverse and beneficial impacts to the Heart Mountain Relocation Center National Historic Landmark.
The BLM complies with NHPA Section 106 for all actions with the potential to adversely impact historic properties (i.e., cultural resources eligible for, or listed on, the NRHP, including those designated as National Historic Landmarks). If historic properties are present, the BLM consults with the SHPO and other interested parties in developing mitigation measures for adversely affected properties. These measures would minimize adverse impacts to the Heart Mountain Relocation Center National Historic Landmark under all of the alternatives.
Under all of the alternatives, the BLM pursues a withdrawal from appropriation under the mining laws for the 72 acres of BLM-administered mineral estate underlying private and other federal agency-administered surface lands in the Heart Mountain Relocation Center National Historic Landmark. Preventing mining activities on areas in the National Historic Landmark would result in beneficial impacts by maintaining the historic setting of the area to its historical significance.
Surface-disturbing activities and ROW development would have similar impacts on the Heart Mountain Relocation Center National Historic Landmark under all alternatives, but their intensity is likely to vary. Therefore, these impacts are analyzed under each alternative. Proactive management would result in varying beneficial impacts to the National Historic Landmark under each alternative.
Oil and gas development, mining, and other surface-disturbing activities would threaten the historical landscape and viewshed around the Heart Mountain Relocation Center National Historic Landmark. Projected surface disturbance under Alternative A (Table 4-1) would result in the potential for alterations of the scenic characteristics in the surrounding landscape that may adversely affect the historical significance of the National Historic Landmark.
ROW authorizations, especially for wind-energy development, also may cause visual impacts that may affect the setting and viewshed of the National Historic Landmark. Under Alternative A, the BLM considers renewable energy development on a case-by-case basis throughout the Planning Area and manages 941,778 acres as ROW avoidance/mitigation areas and 61,416 acres as ROW exclusion areas. Less restrictive ROW management actions would allow for dispersed ROW development and the potential for visual impacts. Therefore, Alternative A would result in potential adverse impacts to the National Historic Landmark from ROW development.
Other than the withdrawal specified under Impacts Common to All Alternatives, no alternative-specific proactive management actions are prescribed for the Heart Mountain Relocation Center National Historic Landmark under Alternative A.
Impacts to the National Historic Landmark from surface disturbance would be similar to, but less than, under Alternative A. Projected surface disturbance under Alternative B (Table 4-1) would result in the smallest potential for alterations of the scenic characteristics in the surrounding landscape that may result in adverse impacts to the setting and viewshed of the National Historic Landmark.
Impacts to the National Historic Landmark from ROW development under Alternative B are similar to, but less than, under Alternative A. Under Alternative B, the Planning Area is open to renewable energy development unless managed as a renewable energy or ROW exclusion or avoidance/mitigation area. The BLM manages 2,717,617 acres as ROW avoidance/mitigation areas and 225,750 acres as ROW exclusion areas, with 246,448 acres open to renewable energy. This alternative consolidates new ROW development more than the other alternatives, which may reduce the potential for impacts to the setting and viewshed of the Heart Mountain Relocation Center National Historic Landmark compared to the other alternatives.
Under Alternative B, the BLM avoids surface-disturbing activities in view within 5 miles (2,736 acres) of the Heart Mountain Relocation Center National Historic Landmark, except within existing utility corridors; manages areas within 3 miles as administratively unavailable for mineral leasing and applies a CSU stipulation in view within 5 miles or the visual horizon; and closes the area within 3 miles and in view within 5 miles to mineral materials disposal. These proactive management actions would provide the greatest benefit to the National Historic Landmark, compared to the other alternatives, by protecting the setting around the National Historic Landmark and contributing to the preservation of its historical integrity.
Impacts to the Heart Mountain Relocation Center National Historic Landmark from surface disturbance would be similar to, but greater than, those under Alternative A. Projected surface disturbance under Alternative C (Table 4-1) would result in the greatest potential for alterations to the viewshed, resulting in adverse impacts to the setting of the National Historic Landmark.
Impacts from ROW development near Heart Mountain Relocation Center National Historic Landmark under Alternative C would be similar to those described for Alternative A, but less than under Alternative A and more than under alternatives B and D. Under Alternative C, the Planning Area is open to renewable energy development unless managed as a ROW exclusion or avoidance/mitigation area. The BLM manages 1,174,335 acres as ROW avoidance/mitigation areas and 7,762 acres as ROW exclusion areas, with 1,425,762 acres open to renewable energy. ROW consolidation under Alternative C would result in fewer adverse impacts than Alternative A, but more than alternatives B and D.
Proactive management under Alternative C would result in fewer beneficial impacts to the Heart Mountain Relocation Center National Historic Landmark than under Alternative B. The BLM does not apply a buffer to prohibit surface-disturbing activities around the National Historic Landmark, but does manage areas within the footprint of the original Heart Mountain Urban Area (912 acres) as administratively unavailable for mineral leasing and closes areas within ¼ mile (255 acres) and in view within 1 mile to mineral materials disposal.
Impacts to the Heart Mountain Relocation Center National Historic Landmark from surface disturbance under Alternative D would be similar to those under Alternative A. Alternative D results in 3 percent more short-term and 17 percent more long-term surface disturbance than Alternative A, with a proportional degree of potential adverse impacts to the National Historic Landmark. Overall, surface disturbance under Alternative D would result in the second highest potential for adverse impacts to the National Historic Landmark.
Impacts to the Heart Mountain Relocation Center National Historic Landmark from ROW development near the National Historic Landmark under Alternative D would be similar to, but less than those under Alternative A, less than under Alternative C, and more than under Alternative B. Under Alternative D, the Planning Area is open to renewable energy development unless managed as a ROW exclusion or avoidance/mitigation area. The BLM manages 2,512,202 acres as ROW avoidance/mitigation areas and 39,003 acres as ROW exclusion areas, with 393,593 acres open to renewable energy. ROW consolidation under Alternative D would be similar to Alternative C, and would result in greater adverse impacts than under Alternative B, but less than under Alternative A.
Proactive management under Alternative D would result in fewer beneficial impacts than under Alternative B, but more than under alternatives A and C. Measures to preserve the viewshed around the Heart Mountain Relocation Center National historic Landmark under Alternative D, including not authorizing undertakings of moderate or strong contrast, except ROWs within the utility corridors (Map 54); requiring all undertakings in the viewshed to have a visual contrast rating and visual simulation, as appropriate; and avoiding or mitigating adverse impacts from all undertakings within the viewshed would protect the National Historic Landmark’s historical setting and contribute to the preservation of its historical integrity. Alternative D also restricts mineral leasing in the vicinity of the National Historic Landmark similarly to, but more than Alternative C, and prohibits mineral materials disposal within the 72 acres of the National Historic Landmark Urban Center. Overall, proactive management actions under Alternative D would protect the historical setting of the National Historic Landmark more than alternatives A and C, but less than Alternative B.