Visual resources

The project is located in Inyo National Forest and is surrounded by tall mountain peaks. With rugged topography, expansive forest landscapes, and numerous lakes, the visual character of the region is one of the primary attractions for visitors.

The proposed plant would be located on vacant land vegetated with pine trees. Nearby, US Highway 395 and State Route 203 (SR 203) provide mountain views and are designated as scenic routes.

Other locations where viewer sensitivity is high are Shady Rest Park and the National Forest System Roads. The US Forest Service (USFS) recognizes that the area possesses many scenic qualities, which need to be conserved.

Visual Quality Objectives for the Proposed Project

Jurisdiction

Federal: The USFS Visual Management System, the Inyo National Forest Land and Resource Management Plan, and the Bureau of Land Management (BLM) Geothermal Leases all require scenery management and preservation.

State: At the state level, the California Scenic Highway Program attends to the preservation of the natural beauty of California.

Local: Local regulations in the Mono County General Plan and Mammoth Lakes General Plan govern development in scenic areas.

Environmental consequences

The proposed power plant would have a base elevation of 50 ft (15.24 m) higher than the existing ones.

The site can be seen from 4-8 miles (6.44-12.87 km) away in certain directions, thereby taking over the landscape from Antelope Springs in the foreground and causing negative visual impacts. Well facilities and pipelines will be visible from certain roads and the foreground.

Construction and related traffic will be visible from several points in the project area throughout the construction period (up to 16 months).

Nighttime construction lighting may be visible from the Mammoth Lakes community.

Under Alternative 4, exploratory wells will not meet “retention,” but instead “partial retention” under the Visual Quality Objective (VQO).

Cumulative impacts

None mentioned.

Mitigation

A Landscape Plan will be implemented by ORNI 50 LLC. The plan will include planting native trees and shrubs at certain places to better hide the well site facilities and pipeline.

The height of pipeline crossovers and expansion loops (square bends so that the pipeline can “flex” as it lengthens and shortens due to heating and cooling) will be decreased in instances where one pipeline crosses over another.

Residual Impacts

Visual impact related to project construction, operation and maintenance of wells and pipelines in areas designated by the USFS with a Visual Quality Objective (VQO) of “retention.” However, these impacts would disappear after decommissioning.

Critique

The Landscape Plan will serve as a useful tool to implement the suggested measures that involve planting vegetation to better hide the project.

Existing geothermal power plant near Highway 395 junction and SR 203 looking West.

View from Highway 395 junction and SR 203 looking North. White arrow indicates new power plant location to be constructed behind the forested knoll. Existing power plant is visible to the right.