Proposed Action Plants

The Proposed Action is not expected to negatively affect federally or state-protected plants. All known records of these species occur beyond the proposed construction areas. Also, the extended drawdown is not expected to diminish or significantly alter the prime habitat for these species, which includes bluffs and wooded side slopes.

Aquatic Animals

The Proposed Action is not expected to affect federally or state-protected aquatic fauna, as no protected aquatic species are known to occur within Boone Reservoir or its tailwater.

Terrestrial Animals

The Proposed Action is not expected to affect bald eagle, common barn owl, common raven, least weasel, southern bog lemming, and southeastern shrew. It is possible that lower fish

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densities in the reservoir during the first 1 to 2 years following refilling might reduce foraging success of bald eagles on fish, but eagles are opportunistic feeders that commonly predate or scavenge from terrestrial sources. As a result of the drawdown, exposure of rock, and drying of shoreline wetlands, least weasel, southern bog lemming, and southeastern shrews may migrate to lower elevations to the exposed rocky habitat (least weasel) or wet habitats along the existing shoreline (southern bog lemmings and southeastern shrews). These species would be

displaced when reservoir levels return in 5 to 7 years. However this is not expected to impact populations of these species.

The reservoir drawdown has exposed a number of cliff-side cave openings that previously were submerged. These cave openings are relatively common along the steep rocky shoreline areas that occur at locations around Boone Reservoir, with many becoming seasonally exposed every winter during the lower headwater elevations targeted under a normal operating schedule. Under the Proposed Action, these caves would persist above water for the 5- to 7-year project duration, before being inundated following the dam remediation. Gray bats, Indiana bats, and northern long-eared bats each have very specific cave requirements, and it is unknown whether these exposed caves would satisfy any of those criteria. However, any bats that colonized these caves during the Interim Operations period would have ample time to displace as the reservoir filling process occurs very gradually over the course of weeks and months, after the completion of the project. Two exceptions would be non-volant (non-flying) juvenile gray bats and bats of all three species in torpor that are not fully awake or aware of their surroundings during winter. Gray bats give birth during late May or early June and are non-volant for

approximately one month following birth. All three of these species of bat can be in torpor from November to March. TVA will monitor these caves periodically to determine if listed bat species utilize these caves and will consult with USFWS under Section 7 of the Endangered Species Act should listed bat species be observed. .

Suitable summer roosting habitat for Indiana bat and northern long-eared bat was observed within the proposed Construction Support Area 2 and the proposed expansion of the

Construction Zone. In early 2015, suitable habitat was also observed within the current Construction Zone and is not being impacted by ongoing activities. TVA has marked the suitable summer roosting habitat in these areas and would avoid any impacts to those trees. Therefore, there would be no impacts to potential summer roosting habitat for Indiana bat or northern long-eared bat in association with the proposed actions.

3.9 HISTORIC AND CULTURAL RESOURCES

3.9.1 Affected Environment

Cultural resources include prehistoric and historic archaeological sites, districts, buildings, structures, and objects, as well as locations of important historic events that lack material evidence of those events. Cultural resources that are listed, or considered eligible for listing, on the National Register of Historic Places (NRHP) are called historic properties. Cultural

resources become historic properties when they possess both integrity and significance. A historic property’s integrity is based on its location, design, setting, materials, workmanship,

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feeling, and association. The significance is established when historic properties meet at least one of the following criteria: (a) are associated with important historical events or are associated with the lives of significant historic persons; (b) embody distinctive characteristics of a type, period, or method of construction; (c) represent the work of a master, or have high artistic value; or (d) have yielded or may yield information important in history or prehistory.

Section 106 of the National Historic Preservation Act (NHPA) requires federal agencies to consider the effects of their proposed undertakings on historic properties and provide the Advisory Council on Historic Properties an opportunity to comment on those effects. TVA determined that the proposed action is an undertaking for purposes of Section 106 compliance. Further, 36 CFR Part 800.3(a) requires agencies to consider whether the proposed undertaking is a type of activity that has the potential to cause effects on historic properties. If the

undertaking is such an activity, then the agency must follow steps outlined in 36 CFR Part 800.4 through 800.13. These steps can be summarized as (1) involving the appropriate consulting parties; (2) defining the area of potential effects (APE); (3) identifying historic properties in the APE; (4) evaluating possible effects of the undertaking on historic properties in the APE; and (5) resolving adverse effects. At 36 CFR Part 800.16, APE is defined as the “geographic area or areas within which the undertaking may directly or indirectly cause alterations in the character or use of historic properties, if any such properties exist”.

Different types of undertakings can have different types of effects. TVA anticipates the

undertaking could have direct physical effects; indirect visual effects; and cumulative effects to historic properties. TVA defined the APE for direct physical effects (D-APE) to be the current Construction Zone (43.6 acres), the proposed expansion of Construction Zone (19.1 Acres), Construction Support Area 1 (71.2 Acres), and Construction Support Area (12.8 Acres) (Figure 1-6). TVA defined the APE for indirect visual effects (V-APE) to be those areas within a ½-mile radius of and with a direct line of site to the D-APE. TVA defined the APE for indirect effects (I- APE) to be the current reservoir “drawdown zone” between 1,382 feet (summer pool elevation) and 1,350 feet (extended drawdown elevation), which is based on the potential for effects to occur later in time.

Archaeological Sites

TVA has completed an archaeological inventory of the entire D-APE and identified no archaeological sites (Pietak and Holland 1998; Wampler 2015; Wells 2015a, 2015b). The V- APE did not warrant an archaeological survey since visually adverse effects to archaeological sites are not anticipated. Multiple archaeological surveys have been conducted within the I-APE (Pietak and Holland 1998; Watkins 2014; S.D. Dean personal communication, 2014). The Pietak and Holland (1998) and Watkins (2014) surveys identified a total of 67 archaeological sites within the I-APE. Of those sites, TVA determined (in consultation with SHPO) that 31 are NRHP ineligible and 36 are potentially eligible. The Dean (2014) survey results will be

documented as part of the PA. TVA estimates that 500 acres will require an archaeological survey to complete the inventory of the I-APE.

Historic Buildings and Structures

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(Prybylski 2015). The Boone Hydroelectric Project is comprised of 10 contributing resources including the Boone Dam Hydroelectric Plant including the Powerhouse, Control Building, Visitors Overlook, Switch Yard, Water Storage Tank, Oil Purification/Storage Building, Recreation Area, and 2 Maintenance Buildings. As noted in Table 1-1, the dam’s earthen embankment is being lowered by 10 feet to allow for initial exploratory grouting activities; because that portion of the embankment is not part of the original design of the dam, the alteration does not detract from the Boone Hydroelectric Project’s historic integrity.

TVA identified 48 buildings within a ½-mile radius of the D-APE which are greater than 45 years of age. TVA determined that 42 buildings are not eligible for the NRHP, and the six remaining buildings may be eligible for the NRHP.

No historic buildings or structures were identified within the I-APE.