Canyon Water Supply Company, and Montana DEQ. The final Instream Flow
Release Plan, incorporating comments received from the consulted
agencies, was filed with the license application.
    During installation and pressure-grouting of the steel penstock
liner, construction of the trifurcation leading to the powerhouse
turbines, and installation of associated valves, minimum flows to the
Beaverhead River would need to be bypassed around the existing
penstock. The applicant estimates that this phase of the construction
process would require approximately 8 to 12 weeks, extending from
October into December. In its Final Instream Flow Release Plan, the
applicant proposes to provide streamflows during this period using
electric pumps mounted on a barge anchored in the project forebay.
After this phase of the construction has been completed, flow would be
released through the existing penstock.
    Prior to the start of construction, the number of primary and
backup pumps would be determined based on the minimum flow release that
would be required by Reclamation during the construction period. The
number of primary and backup pump units would be a function of the
final construction specifications and bypass flow requirements. The
applicant anticipates that one or two pumps would most likely be
required, but it proposes to provide as many pumps as are needed to
pass the minimum flow specified by Reclamation. The applicant provided
cost estimates for the installation of up to four pumps. The applicant
proposes to mount the primary and backup pump units on a platform
anchored in the forebay near the spillway, and to screen the pump
intakes to meet resource agency requirements for fish exclusion.
    Magnetic flow measuring equipment would be installed on each
discharge pipe so that the discharge from each pump can be measured. In
addition, the applicant proposes to install a gaging station
immediately downstream of the project prior to construction.
Reclamation would be consulted prior to construction regarding how the
exchange of flow releases from the regulating outlet to the pumps and
back again would occur, and continuous contact would be maintained
between representatives of the applicant and Reclamation during this
period.
    A diesel generator located above the reservoir shoreline would be
available to provide backup power in the event of a power outage. The
generator would be enclosed in a spill containment unit of sufficient
capacity to handle the diesel generator fuel storage. Additionally, an
earthen berm would be placed around the generator site. The diesel
generator would provide controls for automatic startup and electrical
transfer if an outage occurs. The applicant also proposes to provide
full-time/24-hour staff attendance of the pumping system when flows are
being bypassed around Reclamation's existing intake and outlet works
during construction of the proposed penstock.
Our Analysis
    The applicant's proposal to implement its Final Instream Flow
Release Plan, with provisions to pump flows around the existing
penstock to the Beaverhead River at flows dictated by Reclamation,
would ensure that streamflows and water quality suitable to protect
aquatic life are maintained in the Beaverhead River downstream of the
dam during project construction. Providing stable flow releases would
be especially important to brown trout and mountain whitefish, which
spawn in the Beaverhead River in October and November and rely on
stable river flows for reproductive success.
    The applicant estimates that this phase of the construction process
would require approximately 8 to 12 weeks, extending from October into
December. Elevated flows associated with irrigation demands have
typically ended by late September. The timing of irrigation releases
and the amount of minimum flow to be released after irrigation releases
end are determined jointly by Reclamation and the East Bench Joint
Board of Control, which is composed of the District and the Clark
Canyon Water Supply Company. Minimum flows released during the post-
irrigation season are determined using guidelines based on the amount
of reservoir storage at the beginning of September plus the total
inflow that occurs during July and August (table 3).

Table 3--Clark Canyon Reservoir Release Guidelines (Source: Reclamation,
                                  2006)
------------------------------------------------------------------------
                                                                Minimum
   September 1 Storage Plus  July-August Inflow (acre-feet)       Flow
                                                                 (cfs)
------------------------------------------------------------------------
Less than 80,000.............................................         25
80,000-130,000...............................................         50
130,000-160,000..............................................        100
Greater than 160,000.........................................        200
------------------------------------------------------------------------

    Staff examined the end-of-month storage for Clark Canyon Reservoir
for the years 1965-2016. Over the period of record, end-of-month
storage for the month of September was generally less than 160,000
acre-feet with very few exceptions (Reclamation, 2016). Data for the
most recent three years showed that storage for September ranged from
47,983-59,215 acre-feet (Reclamation,

2016). Given the data, we do not expect that the applicant would be
required to provide a minimum flow above 100 cfs during the pumping
stage of construction. Nevertheless, the applicant commits to being
prepared to release whatever flow is required by Reclamation during the
construction period. Consultation with Reclamation prior to the start
of construction to determine what minimum flows would be required
during the construction period, as the applicant proposes, would ensure
that a sufficient number of primary and backup pumps are installed to
maintain the required minimum release flows. Provision of backup pumps
and a backup generator, as proposed by the applicant, would help to
ensure that the required minimum flow is maintained in the event of a
mechanical failure or power outage. Installation of the backup
generator and fuel storage in a containment unit would help to ensure
that any spills of diesel fuel are contained and do not enter the
waterway.
    Additional provisions proposed by the applicant that would help
ensure flow continuity during project operation include:
     When flows drop below 87.5 cfs (the minimum hydraulic
capacity of the powerhouse), the flow would be gradually transferred to
the main penstock through synchronization between the powerhouse and
the penstock valves. As flow is reduced through the powerhouse valves,
flow would increase correspondingly through the penstock valve, and
vice versa.
     The project is being engineered such that, in the event of
emergency shut down or during a drop in flows that precludes power
generation, the closure of the powerhouse valves and the return of
flows to the normal outlet works would be automatically synchronized to
eliminate the potential for unintended ramping. There would be no
transition between pressurized and non-pressurized flows through the
regulating outlet once the project is operational. Upon completion of
the project, flows exiting the dam would be pressurized at all exit
points except for the spillway.
     A project operator would be on site daily and Reclamation
personnel would be notified immediately in the event of an unplanned
shutdown or in case of any other type of emergency.
    Implementing these measures would help ensure a very low likelihood
of unintended ramping or dewatering of aquatic habitat as a result of
project operation. Also informing Montana DFWP of any unplanned
shutdown would provide that agency with information relevant to its
management of fishery resources downstream of the project.
    Providing 24-hour attendance of the pumping system for the duration
of time that minimum flows are to be maintained by pumping would help
avoid or minimize any adverse effects on aquatic resources caused by
failure or malfunction of any component of the pumping system. Failure
of the pumping system could have catastrophic consequences on fish and
aquatic resources, especially brown trout and whitefish that are known
to spawn during October and November in areas downstream of the dam.
Because the pumps would provide the only means to transfer water from
the reservoir to the river, it is anticipated that streamflows
downstream of the dam would immediately begin to recede in the event of
a pumping system failure. Any potential adverse effects of a pumping
failure would be minimized by having properly trained staff on site to
ensure a return to normal operations as quickly as possible. Further,
installing a water level alarm to detect falling water levels in the
Beaverhead River near the instream flow release point could help alert
onsite staff of any need to activate back-up pumps or address any
unforeseen problems with the pumping system.
    Notifying Montana DEQ and Montana DFWP within 24 hours of any
unauthorized discharge of pollutants, as the applicant proposes in its
CWQMP, would help ensure that best management practices are adhered to
and that any spills are addressed in a timely and thorough manner.
Construction Water Quality Monitoring
    Montana DEQ's condition 2 stipulates the applicant submit a plan to
monitor turbidity, temperature, DO, and TDG during construction. In its
CWQMP, the applicant proposes to monitor DO, temperature, and turbidity
at a site approximately 300 feet downstream of the proposed powerhouse
and parking construction areas while TDG would be monitored immediately
below the spillway pool when flows are being bypassed around
Reclamation's existing intake and outlet works during construction of
the proposed penstock.
    If monitoring indicates that the state of Montana standard for TDG
of 110 percent saturation is exceeded during pumping, the applicant
would reposition the pump outlets until the state standard is met. Data
would be transmitted in real time to the construction manager's trailer
at the construction site, with mean values recorded at 15-minute
intervals. Routine calibration and maintenance of field equipment would
be accomplished in accordance with the manufacturer's guidelines.
    The applicant's plan also includes provisions to take a vertical
profile of dissolved oxygen levels and water temperatures in Clark
Canyon Reservoir prior to commencement of pumping activities to ensure
that reservoir mixing has occurred. If mixing has not occurred, then
the applicant would delay modifying Reclamation's penstock and inlet
works until this determination is made; thereby ensuring that any water
pumped around Reclamation's penstock does not degrade water quality
conditions below the dam.
    For turbidity monitoring, the applicant proposes to use 5 NTU as
background from which to evaluate turbidity levels generated by
construction activities. Should this level be exceeded by more than 5
NTU during construction, the applicant would conduct a ground survey to
determine if there is noticeable sedimentation arising from the
construction area, take a water sample to verify the reading, and also
determine if the probe is functioning properly and clear of algae or
other debris. Any event resulting in a discharge of sediment would be
reported within 24 hours to Montana DEQ and Montana DFWP to determine
the need for corrective measures.
    The applicant proposes to submit annual water quality monitoring
reports to Reclamation, FWS, Montana DFWP, and Montana DEQ by February
15 following each year of construction. Agencies would have 60 days to
review the draft reports and the applicant would submit a final report
to the Commission each year addressing agency comments. The reports
would include the raw data, documentation of any deviations from water
quality criteria, and documentation of procedures to correct any
deviations. In addition to annual reporting, the applicant proposes and
Montana DEQ's condition 7 stipulates that the applicant notify Montana
DEQ and Montana DFWP within 24 hours of any event that results in the
discharge of sediment or pollutants as described above. The applicant
also proposes to file an incident report with the Commission following
the event.
Our Analysis
    Monitoring water temperature, DO, TDG, and turbidity prior to and
during construction as the applicant proposes and as stipulated by
Montana DEQ's condition 2 would ensure that any adverse effects on
water quality are

identified and that appropriate actions are undertaken to protect
aquatic resources in Clark Canyon Reservoir and in the Beaverhead River
downstream of the dam during all phases of construction.
    Available information on water temperature and DO levels in Clark
Canyon Reservoir indicate that the reservoir is typically well-mixed by
late September so that the depth at which water is drawn from the
reservoir during the October start date for pumping flows around the
existing intake and outlet works should have no effect on downstream
water quality conditions. Collecting reservoir profile data prior to
the start of project construction, as the applicant proposes, would
help to determine whether reservoir mixing has occurred and to assess
whether project construction can be initiated without causing any
adverse changes in downstream water quality. If pre-construction water
quality monitoring indicates that temperature and DO are not uniform by
the proposed October start date, delaying the start date of
construction would further ensure that downstream water quality is
protected prior to initiating pumping activities.
    There is some potential that the pumping system used to bypass
flows around the existing intake and outlet works during construction
of the proposed penstock would provide a different level of aeration
than currently occurs in the existing outlet structure, which could
affect DO and TDG concentrations. If the pump discharge lines do not
extend to the base of the spillway, aeration that would occur as flows
pass down the spillway should ensure that DO and TDG concentrations
equilibrate with atmospheric conditions, which would likely improve
water quality for a temporary period compared to existing conditions.
In the unlikely event that water quality conditions during pumping
activities are adversely affected and water quality standards are not
met, this would be detected by the proposed water quality monitoring
program and appropriate measures could be taken (e.g., repositioning
the pump outlets) until Montana DEQ's water quality standards for DO
and TDG are met.
    The proposed temporary pumping facility could affect turbidity
levels downstream by taking in sediment through its intake in the
reservoir, or by disturbance during installation or removal of the
intake. Monitoring turbidity levels downstream of the construction
footprint immediately prior to and during construction as described in
the applicant's CWQMP would alert the construction manager of a spike
in turbidity and the need to determine the cause of the event and any
necessary corrective measures to protect water quality. Because
turbidity levels near the proposed construction footprint are generally
less than 5 NTU during the year, using 5 NTU as a background turbidity
level as the applicant proposes would be more than adequate to identify
when a spike in turbidity has occurred beyond naturally occurring
background levels. Notifying Montana DFWP and Montana DEQ within 24
hours of a discharge of sediment or pollutants would alert the agencies
of these events as they occur and allow for these agencies to provide
timely recommendations to protect water quality and fish resources
downstream during construction.
    Providing annual water quality monitoring reports to the agencies
and the Commission during construction as the applicant proposes would
provide a mechanism to evaluate whether any changes are needed to
achieve water quality standards on a year-to-year basis during
construction. However, in addition to annual reporting, notifying the
agencies within 24 hours of a deviation from water quality criteria,
and submitting an incident report to the Commission following the
incident would enable the Commission and agencies to determine whether
best management practices are being followed and that any needed
corrective actions are addressed in a timely manner.
    Also, notifying Montana DEQ and Montana DFWP within 24 hours of any
discharge of pollutants and submitting an incident report with the
Commission following the event would help ensure that best management
practices are adhered to and that any spills are addressed in a timely
and thorough manner.
Minimum Instream Flows
    The applicant proposes that the project be operated as a run-of-
release project, in which the flows downstream of the project
powerhouse would be dictated by Reclamation, thus the flows would be
identical to the flows that would be released by Reclamation in the
absence of the project. This is consistent with Reclamation's 4(e)
condition 9, which states that the timing, quantity, and location of
water releases and release changes from the facilities would be at the
sole discretion of Reclamation.
    Interior, Upper Missouri Waterkeeper, and Montana Trout Unlimited
recommend that the applicant work closely with water users and federal
and state agencies to improve minimum instream flow conditions in the
Beaverhead River, and support the implementation of the 2006 MOU
between Reclamation and Montana DFWP entitled Betterment of the
Beaverhead River and Valley.
    Interior and Montana Trout Unlimited also recommend that the
applicant contribute to improvements in water use efficiency to enhance
instream flows for fisheries and environmental health of the river.
They recommend that the applicant dedicate 4 percent of the gross
hydropower revenues to funding independent technical studies of water
efficiency improvements or funding on-the-ground water conservation
measures designed to result in instream flow improvements. Interior and
Montana Trout Unlimited recommend that the applicant prepare annual
reports that explain the uses and expenditures of such funds, and the
expected benefits of funded activities. In advance of submitting the
annual report to the Commission, the applicant would provide the report
to Montana DFWP and FWS for a 30-day review, and attach any comments
received on the report when filing it with the Commission.
Our Analysis
    Available information indicates that trout populations in the
Beaverhead River are adversely affected by low flows that occur during
the non-irrigation season and that fish populations in Clark Canyon
Reservoir are adversely affected by low reservoir levels during periods
of drought. Encouraging the implementation of water conservation
strategies in the basin could alleviate adverse conditions that occur
in Clark Canyon Reservoir and in the Beaverhead River during drought
conditions. However, we note that operation of the project as proposed
by the applicant would not cause any changes in the flows in the
Beaverhead River or on water storage levels in Clark Canyon Reservoir.
    The 2006 Reclamation/Montana DFWP MOU includes the following
elements: (1) Identify environmental degradation issues of the
Beaverhead River; (2) investigate possible solutions to correct
degradation issues; (3) review Clark Canyon Reservoir operation to
increase river and reservoir environmental health; (4) explore water
conservation projects; (5) describe fishery goals and fish management
objectives; and (6) work through a collaborative process with
interested groups to develop resource management strategies to improve
the environmental health of Clark Canyon Reservoir and the Beaverhead
River. Implementing the applicant's proposed water quality

monitoring program would assist with identifying any environmental
impacts associated with project construction and operation, and
determine whether measures are needed to address project effects. The
monitoring program would also contribute information on water quality
conditions that would be useful to Reclamation and Montana DFWP as they
pursue implementation of the MOU.
    The applicant's proposal to operate the project to provide flows
determined by Reclamation, consistent with Reclamation's 4(e) condition
9, would ensure that any changes in reservoir operation or flow regimes
implemented under the MOU or through any other agreements that
Reclamation enters into would not be impeded by operation of the
project.
    We make our final recommendation for water efficiency improvements
in section 5.2, Comprehensive Development and Recommended Alternative.
Water Quality Operation Effects
    Montana DEQ's condition 3 stipulates that the applicant maintain DO
levels at saturation (approximately 7.5 mg/L or higher, depending on
the temperature of the reservoir water at the intakes) from June 1
through August 31 and 8.0 mg/L the rest of the year while operating.
Condition 5 stipulates that the applicant submit a plan prior to
construction describing any project design engineering modifications
for maintaining DO at these levels. Condition 4 stipulates that the
applicant maintain TDG levels at 110 percent or lower downstream of the
project while operating.
    Diverting water through the applicant's proposed penstock and
turbines at Clark Canyon Dam has the potential to reduce DO
concentrations downstream compared to current conditions by reducing
the turbulence and the entrainment of gases in water exiting the
powerhouse. Reduced DO concentrations may limit salmonid growth and
reproduction and delay embryonic development and hatching of juveniles
if concentrations remain low for extended periods (EPRI, 1990). In
order to address potential DO and other water quality concerns during
project operation and to comply with Montana DEQ's certification
conditions, the applicant proposes to construct and operate an aeration
basin downstream of the powerhouse and to implement its Revised DOEP
during project operation which includes: (1) Procedures for monitoring
and reporting temperature, DO, and TDG levels in project waters for a
minimum of five years following initial project operation; (2)
procedures for enhancing DO concentrations for water exiting the
tailrace; and (3) corrective measures and emergency shutdown procedures
to be implemented if deviations from state water quality criteria occur
during project operation. The applicant states that the plan was
developed in consultation with Reclamation, FWS, Montana DFWP, and
Montana DEQ. Water quality monitoring provisions included in the plan
are evaluated in section <IP_ADDRESS>, Post-Construction Water Quality
Monitoring.
    The proposed aeration basin would consist of three 45-foot-long,
10-foot-wide frames containing 330 diffusers with the capacity to add
additional frames if needed. The diffuser system would feature two
mechanical blowers, an electronic control system, and ducted aeration
diffuser disks to inject fine bubbles of air into the water column to
provide the additional aeration. The applicant states that the blower
and diffuser system would be designed with the capacity to elevate DO
levels by a maximum of 7.5 mg/L before the water enters the Beaverhead
River and could be adjusted based on the level of aeration needed to
meet state criteria. The applicant anticipates that operation of the
aeration basin would likely occur from June through mid-September each
year, which is the time that DO concentrations at the bottom of the
reservoir (i.e., near the depth of the intake) are expected to be at
their lowest levels of the year.
    The blower for the aeration basin would include sensors to monitor
flow rates and could be adjusted by the operator using controls located
both remotely and in the powerhouse. The volume of air supplied by the
blower would be based on the level of DO enhancement that is required
for a given volume of water and would take into account empirically
observed oxygen transfer rates. The applicant states that in early
summer, as DO levels decline, the air diffusers in the aeration basin
would be gradually brought online to maintain DO concentrations in the
Beaverhead River downstream. If DO concentrations decline to such
levels that the diffusers are insufficient to meet Montana DEQ's DO
criteria (i.e., 7.5-8.0 mg/L) during these months, then flows would be
gradually shifted through the cone valves to the existing project works
to provide additional aeration beyond that provided by the aeration
basin alone.\19\ This shift in flow would occur either automatically
based on feedback from the applicant's water quality monitoring probes
or manually by an operator as needed.
---------------------------------------------------------------------------

    \19\ The applicant states the shift of partial flows to the cone
valve can function to aerate water using the existing outlet works
in addition to the proposed aeration basin thereby potentially
further enhancing DO levels beyond what the aeration basin would
provide alone.
---------------------------------------------------------------------------

    In an emergency shutdown or if probes at compliance monitoring Site
3 located approximately 300 feet downstream of the project in the
Beaverhead River (described further below in section <IP_ADDRESS> Post-
Construction Water Quality Monitoring) show that Montana DEQ's DO
criteria cannot be met, the project would automatically trip offline,
triggering the closing of the wicket gates on the turbines and
simultaneously opening the cone valve, transferring all flows through
the cone valves at the existing project works. If blowers malfunction
during the time that the applicant needs to provide additional
aeration, the project would remain offline until the backup blower is
connected or the blowers are replaced. The applicant also proposes to
notify Reclamation immediately in the event of an unplanned shutdown or
any other type of emergency that occurs during project operation.
    Montana DFWP recommends that the applicant's aeration system be
designed to achieve water quality standards downstream when water
entering the project works has DO concentrations of 0 mg/L or the
applicant should be willing to shut the project down. In its reply
comments, the applicant reiterated that its proposed aeration basin is
designed to provide the necessary level of DO enhancement downstream,
but in any case it would shift flows through the existing outlet works
or shut the project down as a last resort to meet water quality
standards.
    In addition, Montana DFWP and Upper Missouri Waterkeeper recommend
that the applicant evaluate the need for dam infrastructure alterations
and/or changes in long-term operations to minimize downstream turbidity
resulting from entrainment of organic material or inorganic fine
sediment from the reservoir into the project works. In its reply
comments, the applicant stated that the Clark Canyon Project would not
alter the depth of the reservoir intake, or the rate, volume, or
velocity of water withdrawn. As a result, the applicant contends that
minimizing entrainment of suspended organic and inorganic material is
not within its operational control.

Our Analysis
    Installation of turbines at the outlet works as proposed by the
applicant has the potential to alter TDG levels downstream of the
project. Under existing conditions, water leaving the outlet structures
is subject to aeration and plunging as it exits the outlet works, which
likely causes supersaturated TDG levels that have been documented in
the dam tailrace during the months of June through September (see
Figure 8). Elevated TDG levels may injure or kill fish that are exposed
depending on the level of TDG supersaturation, species, life stage,
depth, condition of the aquatic organism, and temperature of the water
(Beeman et al., 2003). Passing water through the turbines would reduce
the plunging effect and turbulence that occur under existing
conditions, as well as the potential for entrained air to enter
solution under pressure in the outlet works and in the spillway pool,
thereby reducing the potential for TDG supersaturation. Thus, when
flows are within the operating range of the project (i.e., between 87.5
and 700 cfs), we expect that the potential for TDG supersaturation
would be reduced compared to existing conditions which would benefit
aquatic resources in the Beaverhead River downstream of the dam. Based
on mean monthly flow release data for Clark Canyon Dam, we expect flow
releases to be within this range a majority of the time (see figures 3
and 4). While it is reasonable to expect that TDG levels would be
lowered during project operation (as compared to not operating the
project), it is difficult to predict whether Montana DEQ's criteria of
110 percent saturation could be maintained at all times during project
operation.
    This would especially be the case when flow release requirements
exceed the 700-cfs hydraulic capacity of the powerhouse. Under this
scenario, additional flows would bypass the powerhouse penstock at the
trifurcation and would be discharged through the existing outlet works,
and in rare circumstances, through the spillway. As previously noted,
TDG supersaturation frequently occurs when flows are released through
the existing outlet works at the dam. Therefore, any time that flows
exceed the 700-cfs capacity of the powerhouse which can occur at times
during the peak summer irrigation season (see figures 3 and 4), it
would not be unreasonable to expect that TDG supersaturation could
occur. We would also expect that TDG supersaturation may occur if flows
are partially shifted through the existing outlet works to enhance DO
beyond what the applicant's proposed aeration basin would provide alone
or if the project is shut down and all flows are released through the
existing outlet works.
    According to its Revised DOEP, the applicant plans to take an
adaptive management approach to correct any deviations from state water
quality criteria, including TDG levels that occur during operation. At
this time, we are not aware of any additional potential measures that
could be implemented at the project to minimize TDG levels; therefore,
we assume that the project would be required to cease operation should
TDG levels exceed the 110 percent saturation criteria stipulated by
Montana DEQ's condition 4 similar to what would occur if DO criteria
aren't met. Under a shutdown scenario, supersaturation of gases may
occur at times during the summer and early fall as is typical under
existing conditions until any future corrective actions are identified
and implemented.
    Although reduced turbulence in the tailrace area could benefit
aquatic resources by reducing the frequency and extent of gas
supersaturation, it could also decrease DO concentrations in the
Beaverhead River by reducing the degree of aeration that occurs to
water that is discharged downstream of the dam. Water currently
discharges through the dam's outlet works under turbulent conditions,
which tend to entrain atmospheric gases, thus increasing DO
concentrations relative to Clark Canyon reservoir background levels. In
contrast, discharging water through a powerhouse would reduce the
turbulence and plunging effect and thus capacity for DO entrainment.
The potential to pass water with decreased DO concentrations would be
greatest in July, August, and September when DO concentrations at the
bottom of the reservoir (near the depth of the intake) would be
expected to be at the lowest levels of the year (i.e., approaching 0
mg/L). Since baseline information indicates that DO levels in the upper
Beaverhead River can fall below the 7.5-8.0 mg/L criteria for trout
under existing aeration conditions, it appears likely that some level
of DO enhancement would be necessary to ensure compliance with the
state DO criteria during project operation.
    Early life stages of trout begin to see declines in their growth
rates when DO levels fall below 8 mg/L and cannot survive in extremely
hypoxic conditions when DO levels fall below 1-3 mg/L (EPRI, 1990).
Because baseline information indicates that DO levels in the upper
Beaverhead River can at times fall below the 7.5-8.0 mg/L criteria in
the summer months, providing the necessary aeration to achieve this
criteria throughout the summer would enhance water quality and provide
a benefit to aquatic resources during these months, particularly early
life stages of trout that are typically more vulnerable to low DO
levels (EPRI, 1990). Foust et al. (2008) determined that an air
admission system is a particularly cost-effective method for improving
DO conditions in a hydroelectric project tailrace and EPRI (2002)
states that tailrace diffusers are widely accepted as devices capable
of providing supplemental aeration. A similar aeration basin and
diffuser array was built and operating effectively at the Island Park
Hydroelectric Project (FERC Project No. 2973) in Idaho. Water quality
monitoring reports filed from 2001-2016 confirmed that the Island Park
Hydroelectric Project was successful at meeting state DO standards of
7.0 mg/L approximately 99 percent of the time during that period.\20\
Given the information available, we anticipate that using a similar
aeration basin and tailrace diffuser array to inject air into the water
column to provide at least 7.5 mg/L of DO as the applicant proposes
would maintain DO concentrations downstream to support all life stages
of trout even when source reservoir levels are approaching 0 mg/L.
Shifting flows to the existing outlet structures as needed to either
achieve a level of 8.0 mg/L or shutting the project down and passing
all flows through Reclamation's outlet works would ensure that project
operation does not degrade water quality conditions relative to
existing conditions and ensure that the applicant complies with DO
levels stipulated by Montana DEQ's condition 3 while operating.
Diverting all flows through the existing project works in the event of
a blower failure or during an emergency shutdown would further ensure
that existing water quality conditions are maintained downstream
consistent with Montana DFWP's recommendation.
---------------------------------------------------------------------------

    \20\ See annual water quality monitoring reports for the Island
Park Hydroelectric Project (FERC Project No. 2973) filed on November
2, 2001; April 22, 2002; August 25, 2003; July 9, 2004; August 8,
2005; June 27, 2006; October 3, 2007; December 31, 2008; November
12, 2009; December 6, 2010; and March 16, 2016.
---------------------------------------------------------------------------

    In regard to Montana DFWP's and Upper Missouri Waterkeeper's
recommendations that the applicant evaluate the need for dam
infrastructure alterations and/or changes in long-term operations to
minimize downstream turbidity, we echo the applicant's reply comment
that it wouldn't alter the depth of the reservoir intake, or the rate,

volume, or velocity of water withdrawn as these are determined solely
by Reclamation. Therefore, we are not aware of what changes to dam
infrastructure or operations would result from the recommended
evaluation to be able to sufficiently evaluate this measure. The
applicant already proposes to implement other soil and erosion control
measures during construction (i.e., implementing its ESCP and CWQMP)
which should inform how construction of the proposed penstock and
outlet works affects downstream turbidity. Given these measures and the
restrictions listed above, it is unclear what additional water quality
benefit would be gained by requiring the applicant to conduct the
recommended evaluation.
Post-Construction Water Quality Monitoring
    Montana DEQ's condition 1 stipulates that the applicant conduct
water quality monitoring for temperature, DO, and TDG for a minimum of
the first five years of project operation and each year thereafter
while discharging from July through October, unless Montana DEQ
determines that additional monitoring is not warranted based on a
review of the monitoring results for the first five years of project
operation. Condition 6 stipulates that the project shut down
automatically if DO levels fall below Montana DEQ standards and that a
second, redundant DO probe be deployed at site 3 to ensure compliance
with DO criteria during project operation. Condition 6 also stipulates
that in the event that automated alarms indicate that water quality
standards may have been exceeded (i.e., TDG or temperature criteria),
that an on-call operator be required to arrive within 30 minutes to
evaluate the causes of the non-compliance reading. Condition 11
stipulates that the applicant meet annually with all watershed
stakeholders to discuss water quality monitoring efforts associated
with project operation.\21\
---------------------------------------------------------------------------

    \21\ Montana DEQ clarified in a phone conversation with staff
that ``watershed stakeholders'' includes state and federal agencies,
non-governmental organizations, and any interested members of the
public. See telephone record summary between FERC and Montana DEQ
filed on June 9, 2016.
---------------------------------------------------------------------------

    In its Revised DOEP, the applicant proposes to continuously monitor
TDG, DO and water temperature for at least the first five years of
project operation consistent with Montana DEQ's condition 1. The
applicant would monitor DO and temperature at three sites and TDG at
two sites during this initial monitoring period (table 4).

           Table 4--Water Quality Monitoring During Operation
           [Source: License application as modified by staff]
------------------------------------------------------------------------
                                    Monitoring
            Parameter                site \a\    Frequency and duration
------------------------------------------------------------------------
Temperature ([deg]C).............      1, 2, 3  Continuous for a minimum
                                                 of first five years of
                                                 project operation.
Dissolved Oxygen (mg/L and             1, 2, 3  Continuous for a minimum
 percent saturation) \b\.                        of first five years of
                                                 project operation.
Total Dissolved Gas (percent              2, 3  Continuous for a minimum
 saturation).                                    of first five years of
                                                 project operation.
------------------------------------------------------------------------
Notes: [deg]C--degrees Celsius; mg/L--milligram per liter.
\a\ Site 1 is small chamber located upstream of proposed turbines. Site
  2 is located in the proposed aeration basin. Site 3 is located about
  300 feet downstream of the project in the Beaverhead River.
\b\ Site 3 would also contain a second redundant probe to monitor DO
  levels in the Beaverhead River for the first year of project operation
  and then each year thereafter from June 1-September 14, subject to
  approval from Montana DEQ and Montana DFWP.

    Temperature and DO levels of the intake water would be monitored by
diverting small amounts of water from the project penstock upstream of
the turbines into a small pressurized chamber containing a monitoring
probe (Site 1) that would continuously transmit data to the powerhouse.
Probes would also be deployed in the aeration basin (Site 2) and at a
site approximately 300 feet downstream of the project in the Beaverhead
River (Site 3). A second redundant probe to ``double-check'' DO
concentrations would also be deployed at Site 3 consistent with Montana
DEQ's condition 6 for the first monitoring year and then from June 1
through September 15 each year thereafter or until the DO criteria is
met for 14 consecutive days without supplemental aeration, whichever
date is later, subject to approval from Montana DEQ and Montana DFWP.
The applicant also states that Montana DEQ or Montana DFWP can request
to extended or shortened deployment of the redundant probe at Site 3 if
necessary.
    As discussed in section <IP_ADDRESS>, Water Quality Operation Effects,
blower controls would include a bypass that would allow full flows to
be automatically routed through the existing cone valves in the event
of an emergency shutdown, or if DO criteria cannot be met. If probes at
Site 3 indicate that DO levels are lowering and approaching Montana
DEQ's DO criteria, flows would gradually shift to the cone valves in
the existing outlet works to provide additional aeration beyond what
the aeration basin could provide alone. If either probe at Site 3
registers DO levels that fall below compliance levels, the project
would automatically trip offline, and all water would be diverted
through the cone valves consistent with Montana DEQ's condition 6.
    In addition to the automatic shutdown procedures described above, a
powerhouse operator would oversee compliance with Montana DEQ's water
quality standards and would take action in the event of a non-
compliance reading for temperature, TDG, or if only one of the probes
at Site 3 indicate that DO criteria is not being met. The operator
would visit the powerhouse at least once daily during all phases of
operation and would determine the ability of the aeration basin to
provide sufficient aeration. If a non-compliance reading for
temperature or TDG occurs at Site 3 or if only one probe indicates non-
compliance with DO criteria, the operator would immediately investigate
and determine if corrective actions, such as shutting the project down,
is warranted.
    Whenever the operator is not at the powerhouse, a series of
automated alarms would dispatch an on-call operator to the powerhouse
within 30 minutes following a non-compliance reading consistent with
the procedures stipulated by Montana DEQ's condition 6. If the operator
is not able to reach the powerhouse for any reason, or if the cause of
any noncompliance reading cannot be determined, the project would be
manually shut down either at the powerhouse or remotely and all water
would be diverted through the cone valves at the existing project
works. Thus, the applicant states that whenever

compliance with state water quality standards for DO, TDG, and
temperature cannot be met due to project operations, the project would
be offline and all flows would be diverted through the existing project
works until further corrective actions, in consultation with the
agencies, could be identified and implemented.
    Although water quality would be monitored continuously, the
applicant proposes to log and store hourly data for reporting purposes
and to submit annual monitoring reports to Reclamation, Montana DEQ,
Montana DFWP, and FWS for review by March 1 for the prior calendar
year.\22\ The reports would include the raw data, identify any
deviations from water quality criteria, and recommended actions to
correct any deviations. At the end of the five-year monitoring period,
the applicant would file a report that includes recommendations for any
potential future monitoring, and identify which parameters, if any,
should be monitored. The applicant's Revised DOEP states that
monitoring of any parameter could be extended beyond the initial five-
year monitoring period at the discretion of Montana DEQ following
review of the five-year monitoring results. In addition, the applicant
includes a provision in its Revised DOEP to notify Reclamation, Montana
DEQ, and Montana DFWP within 24 hours of any deviation from water
quality criteria.
---------------------------------------------------------------------------

    \22\ The applicant agreed to send all post-construction annual
water quality monitoring reports to FWS in addition to the other
agencies in their reply comments filed on April 8, 2016.
---------------------------------------------------------------------------

    Upper Missouri Waterkeeper recommends that the applicant tier
operation of oxygen supplementation systems to ongoing monitoring of
hypolimnion conditions in the reservoir to ensure the system in fact
discharges water that achieves water quality standards and to consider
immediate shutdown of diversions if water quality is shown through
monitoring to be negatively affected downstream. In its reply comments,
the applicant states that implementation of its Revised DOEP, which
includes water quality monitoring compliance sites and corrective
measures that would be taken, would ensure that adequate DO
concentrations are maintained during project operation.
    Upper Missouri Waterkeeper recommends that the applicant support
ongoing studies evaluating turbidity and nutrient pollution events
occurring in the project vicinity and to develop and implement an
adaptive management plan that addresses these concerns based on the
results of those studies. In its reply comments, the applicant states
that the proposed project has no nexus to the upstream land-use
practices and subsequent nutrient loading to the Clark Canyon Reservoir
and that it is beyond their control to eliminate or mitigate water
quality impacts manifested from upstream land-use practices and
reservoir operations.
    Montana DFWP recommends that the applicant conduct water quality
monitoring at three additional sites for a minimum of three years to
empirically assess water quality dynamics within the mixing zone in the
Beaverhead River downstream of the project prior to selecting a
permanent site in consultation with Montana DEQ and Montana DFWP.
Specifically, Montana DFWP recommends the additional sites be located:
(1) Immediately downstream of the cone valve; (2) 100 feet downstream
of the project; and (3) 200 feet downstream of the project. Upper
Missouri Waterkeeper also recommends that the applicant consider
additional upstream and downstream monitoring sites as part of its
water quality monitoring program. In its reply comments, the applicant
states that its water quality compliance sites were selected in
consultation with Montana DEQ under the previous licensing process but
that it would collaborate with Montana DFWP and Montana DEQ as needed.
Our Analysis
    Monitoring TDG, DO, and water temperature for a minimum of five
years during project operation as proposed by the applicant and as
stipulated by Montana DEQ's condition 1 would document compliance with
state water quality criteria and help identify whether the project is
adequately protecting and enhancing water quality conditions and
aquatic resources of the Beaverhead River over a range of hydrologic
and meteorological conditions encountered during the monitoring period.
This would be especially important for TDG and DO, two parameters that
are expected to be affected by project operation.
    Monitoring DO concentrations of reservoir water at Site 1 as the
applicant proposes and as recommended by Upper Missouri Waterkeeper
would alert the project operator of the need to operate the aeration
basin to maintain adequate water quality downstream. Monitoring DO at
Site 2 in the aeration basin would confirm the amount of additional
aeration being provided by the diffusers when the aeration basin is
operating. Monitoring DO at Site 3 in the Beaverhead River downstream
of the project would help confirm that DO enhancement measures are
effective at maintaining adequate DO levels downstream of the project.
Deploying a redundant probe at Site 3 as proposed by the applicant and
as stipulated by Montana DEQ's condition 6 would ensure that the
equipment is working properly for the first year of project operation
and each additional year it is deployed.
    However, if monitoring ceases after the first five years of project
operation, it is unclear how the applicant would ensure compliance with
Montana DEQ's DO, TDG and temperature criteria beyond the initial
monitoring period. The applicant and Montana DEQ did not identify what
criteria would be used to determine that further monitoring would not
be necessary, leaving that to occur in consultation with the agencies
based on the five-year monitoring results. Presumably, the annual
reports would show that with supplemental aeration that DO and TDG
levels are always meeting or better than state water quality criteria.
Consequently, the applicant would then be able to identify a set
timeframe for operating the diffusers each year rather than tying
operation of the diffusers to the results of DO monitoring. Operating
the diffusers on this as-yet unidentified set schedule may cause DO
levels to fall below state standards at certain times outside of this
set period. Thus, extending the DO monitoring period through the term
of any license issued would provide a means to track that DO
enhancement equipment is working properly and that adequate DO levels
are maintained at all times downstream for the protection of aquatic
resources.
    Monitoring TDG levels in the aeration basin at Site 2 and in the
Beaverhead River downstream of the project at Site 3 would confirm
whether the project reduces TDG levels from October through April and
also determine whether the project complies with Montana DEQ's TDG
standard at other times to protect fish and other aquatic resources
downstream. Our analysis in section <IP_ADDRESS>, Water Quality Operation
Effects, indicates that the project may still cause exceedances of
Montana DEQ's TDG criteria during certain times of the year (i.e., when
DO enhancement is occurring and when flow release requirements exceed
the 700 cfs capacity of the project). Thus, extending the monitoring
period for TDG through the license term would allow the applicant,
resource agencies and Commission staff track these events as they
occur, and make informed decisions on the need for corrective measures.

    Deploying probes at the cone valve and 100, 200, and 300 feet below
the project, as recommended by Montana DFW and Upper Missouri
Waterkeeper would permit the applicant to determine the extent of the
mixing zone and potentially the best place to document compliance with
DO and TDG levels. According to Urban et al (2008), the factors
contributing to TDG concentrations in river systems downstream of a dam
changes with distance. Elevated TDG levels in hydropower releases are
generally caused by the entrainment of air in spillway releases and the
subsequent exchange of atmospheric gasses into solution during passage
through the stilling basin. Aerated water plunging off steep drops into
pools is the typical mechanism by which entrained air is forced into
solution causing gas supersaturation. These interactions cause TDG to
fluctuate for a short distance downstream of the plunge or release
point before TDG levels plateau and remain plateaued often for several
miles downstream. This was consistent with the applicant's water
quality sampling results from 2009 which showed that TDG saturation
levels slightly reduced as water moved downstream from the dam but
quickly plateaued and still remained above state criteria at times as
much as 5.7 miles downstream of the project. Given the documented small
changes in TDG levels and because conditions downstream are likely to
be better represented by the applicant's proposed monitoring site than
the turbulent mixing zone, it is unclear what additional benefits to
aquatic resources would be derived from monitoring DO and TDG levels
within the mixing zone.
    Because the project would be operated run-of-release and would
withdraw water from the same depth and through the existing intake
structure, operation of the project should not cause any change in
water temperature in the Beaverhead River downstream of the project. If
initial project operation causes any unforeseen adverse effects on
downstream water temperatures, consulting with the agencies on the
annual reports and extending the monitoring program beyond the initial
five-year monitoring period would help ensure that any modifications
needed to protect beneficial uses could be developed and implemented,
if warranted.
    Conducting additional water quality monitoring at upstream sites as
recommended by Upper Missouri Waterkeeper would provide general
information on water quality conditions within the Clark Canyon
Reservoir above the intake as well as possibly in tributaries feeding
the reservoir but it is unclear what nexus this would have to the
project as these areas would not be affected by the project.
    Supporting ongoing studies evaluating turbidity and nutrient
pollution events occurring in the watershed and participating in the
development of an adaptive management plan with other regional entities
as recommended by Upper Missouri Waterkeeper would likely provide some
information on specific land-use practices and upstream sources of
nutrient loading of project waters to support ongoing watershed
management efforts. However, it is unclear what nexus this effort has
to the effects of the project and at this time we are not able to
evaluate specific actions that would be required by the as-yet
undeveloped adaptive management plan. However, implementing the
applicant's proposed water quality monitoring program would assist with
identifying any effects associated with project construction and
operation, and determine whether measures are needed to address project
effects. The monitoring program would also contribute information on
water quality conditions that would be useful to entities as they
conduct future studies addressing nutrient pollution events and their
effects on aquatic resources in the project area.
    Also, the applicant's proposal to operate the project to provide
flows determined by Reclamation, consistent with Reclamation's 4(e)
condition 9, would ensure that any changes in reservoir operation or
flow regimes implemented under any future adaptive management plan that
Reclamation enters into would not be impeded by operation of the
project.
    Submitting annual water quality monitoring reports to the agencies
would provide a mechanism to evaluate whether any changes are needed to
achieve water quality standards on a year-to-year basis during the
initial few years of project operation. Holding an annual meeting with
watershed stakeholders to discuss water quality monitoring efforts as
stipulated by Montana DEQ's condition 11 would provide another
mechanism to evaluate whether any changes are needed on a yearly basis.
    Notifying Reclamation, Montana DEQ, and Montana DFWP within 24
hours of any deviation from water temperature, DO, or TDG requirements
as the applicant proposes would allow the agencies to provide timely
input on corrective actions needed to protect aquatic resources as they
occur. However, also submitting an incident report with the Commission
within 30 days following any deviation from water quality criteria
would enable the Commission to review actions taken by the applicant in
the short-term when these deviations occur and would facilitate
Commission administration of the license.
    Also, notifying Montana DFWP in addition to Reclamation immediately
in the event of an unplanned shutdown or other operating emergency
would ensure that Montana DFWP provides input on any corrective actions
needed to protect water quality and fish resources in the event of an
unplanned shutdown.
Fish Entrainment
    Entrainment of fish from Clark Canyon Reservoir during project
construction and operation could cause some reduction in fish
populations in Clark Canyon Reservoir, and installation of the proposed
Francis turbines could increase the mortality rate of entrained fish
and reduce the number of fish that are recruited to downstream fish
populations.
    During project construction, the applicant proposes to screen the
pump intakes to meet resource agency requirements for fish exclusion
using 0.5-inch mesh screens of sufficient size to limit approach
velocities to a maximum of 1.0 foot per second.
    Interior and Montana Trout Unlimited recommend that the applicant
prepare, in consultation with Montana DFWP and FWS, a feasibility
assessment of technical procedures to evaluate the effects of fish
entrainment (including pressure differential effects) and impingement
of the dam outlet and project works, to include monitoring a range of
water supply and operating conditions. These entities recommend that,
based on the feasibility assessment, the reviewing agencies and the
Commission determine whether monitoring or preventive measures to avoid
or minimize damage and mortality of native fish would be required.
Our Analysis
    Although the applicant does not specify the depth from which the
pumps would withdraw water from Clark Canyon Reservoir during project
construction, it is expected that the water would likely be withdrawn
from a shallow depth to minimize pipe length and pumping costs and to
facilitate the inspection and maintenance of the proposed intake
screens. Because the depth of the intakes would be much shallower than
the existing dam intake, the potential for fish entrainment would

differ from existing conditions and from project operation, when flows
would pass through the existing dam intake structure.
    Screening the pump intakes as proposed by the applicant would limit
the potential for increasing the entrainment rates of fish species that
use shallower areas of the reservoir, and would limit the potential for
adversely affecting fish populations in the reservoir during project
construction.
    The fish entrainment feasibility assessment recommended by Interior
and Montana Trout Unlimited would determine what, if any, procedures
are possible to study the magnitude of fish entrainment and the
mortality rate of fish passing through the outlet works, with the
ultimate goal of determining whether measures to reduce entrainment are
warranted to minimize injury and mortality of fish.
    Numerous studies of resident fish entrainment and mortality have
been conducted at hydroelectric projects over the past several decades.
Comprehensive reviews of these studies have been done by FERC (1995),
the Electric Power Research Institute (EPRI, 1997, 1992), and Winchell
et al. (2000). While none of these studies specifically evaluated the
entrainment potential of resident trout, CH2M HILL (2007) summarized
the results of several trout entrainment studies conducted at
hydropower projects in the Pacific Northwest. The study reports
summarized in the document suggest that the type of analysis requested
by Interior and Montana Trout Unlimited could be conducted at the Clark
Canyon Dam Project, and may be effective at developing estimates of
entrainment and mortality if baseline information is lacking. In this
instance, however, sufficient information appears to exist to describe
how entrainment rates might change between baseline conditions and
proposed project operation. Project operation would have no effect on
the rate of fish entrained from Clark Canyon Reservoir because the
project would not alter the timing, rate, or volume of water
withdrawals, and all water passing the dam would pass via the existing
deep intake and outlet structure (and by the spillway during spill
events), as it does under existing conditions. During project
operation, however, it is possible that the mortality rate of fish that
are entrained into the intake facilities on the dam may increase due to
the routing of fish through the turbines instead of the existing outlet
works.
    The best available information suggests that the mortality rate of
entrained fish under existing conditions appears to be quite high. In
its comments under the previous license issued for the Clark Canyon
project (i.e., P-12429), Montana DFWP stated that adult burbot
entrained and sampled in 1984 exhibited a very high incidence of
mortality, with most of the dead fish exhibiting extremely distended
swim bladders. Further, Montana DFWP indicated that it is highly
unlikely that brown or rainbow trout entrained under existing
conditions can survive the pressure differential that occurs when fish
are entrained into the deep intake in the reservoir and discharged
through the existing outlet works (Clark Canyon Hydro, LLC, 2006).\23\
---------------------------------------------------------------------------

    \23\ See section E.4 of the final license application filed on
July 7, 2006 under FERC Project No. 12429.
---------------------------------------------------------------------------

    It is unlikely that the addition of a penstock and turbines would
alter the existing pressure-induced mortality rates of fish entrained
into the dam. As previously noted, the project would not alter the
depth of the intake, or the rate, volume, or velocity of water
withdrawal. Therefore, similar to existing conditions, fish would pass
through the turbines having been acclimated to the pressures of the
deep reservoir and would experience rapid depressurization when they
are exposed to atmospheric pressures in the relatively shallow
tailrace. Because the mortality rate of fish passing through the
existing outlet works likely approaches 100 percent based on the
available information, any additional turbine-induced injury caused by
mechanical strike or shear effects would not result in additional fish
losses.
    The fish entrainment feasibility assessment recommended by Interior
and Montana Trout Unlimited would ultimately determine whether measures
to reduce entrainment are warranted to minimize damage and mortality of
native fish. The probable outcome of this evaluation would be to
determine whether a fish screen to preclude fish from exiting the
reservoir would be appropriate. However, installing and maintaining a
fish screen at the existing intake structure would be a substantial
undertaking given the depth of the intake.
    Finally, the fishery in the Beaverhead River consists of self-
reproducing populations of brown and rainbow trout. Any increase in the
mortality rate of fish that are entrained from Clark Canyon Reservoir,
if it were to occur, is unlikely to affect the fishery for these
species. Brown trout, the dominant trout species in the Beaverhead
River, are not abundant in Clark Canyon Reservoir, and as a result,
only small numbers of this species are likely to be entrained. Any
rainbow trout that survived passage through the existing outlet works
would likely be stocked fish that were hatched and reared in a hatchery
environment, and are not likely to be as well adapted to conditions in
the Beaverhead River as naturally spawned fish recruited from the
existing, self-sustaining population.
Cumulative Effects
    Montana DEQ put the Beaverhead River as well as several tributaries
to Clark Canyon Reservoir on the list of impaired waterbodies (CWA
section 303[d]) for violations of state water quality standards. The
listing of these waterbodies on the 303(d) list triggered the
development of a TMDL for each parameter listed. TMDLs are designed to
limit the inputs of potentially degrading agents to waterbodies by
limiting the sources responsible for the degradation. Future
implementation of TMDLs for tributaries to Clark Canyon Reservoir and
the Beaverhead River could have a cumulative benefit of reducing
harmful algal blooms caused by excessive nutrient inputs from several
upstream and downstream sources within the watershed. However, because
the project would not contribute to or affect such inputs, constructing
and operating the project would not directly or cumulatively affect
nutrient levels within the tributaries or the reservoir that may cause
algal blooms.
    DO in the tailrace has been shown to fall below the state criteria
of 8 mg/L at times during the summer and early fall when early life
stages of fish are present. Project operation could further reduce DO
concentrations in the tailrace. However, implementing the applicant's
DO enhancement program would maintain adequate DO concentrations in the
project tailrace throughout the year and potentially enhance DO levels
in the summer months compared to existing conditions. Monitoring DO
levels in the aeration basin and downstream would ensure that DO
enhancement measures are successful at meeting state DO criteria during
project operation.
    The proposed project would likely cumulatively contribute to
efforts to improve water quality in the Beaverhead River by lowering
TDG concentrations in the project tailrace at least during the months
of October through April. Monitoring TDG levels within the aeration
basin and downstream would inform whether additional corrective actions
need to be taken to maintain compliance with state TDG criteria.
    Overall, construction and operation of the project is likely to
cause cumulative enhancement to aquatic resources within the area
defined for our

cumulative analysis due to DO enhancement in the summer months and the
lowering of harmful TDG concentrations during the late fall compared to
existing conditions.

3.3.3 Terrestrial Resources

<IP_ADDRESS> Affected Environment
Vegetation
    Clark Canyon Dam and Reservoir are located within the Beaverhead
Mountains Ecoregion, which extends from the Centennial Mountains south
of Red Rock Lakes National Wildlife Refuge in southwestern Montana,
west to the Continental divide along the Beaverhead Mountains, and
includes the headwaters for the Beaverhead, Madison, and Big Hole
rivers.
    Shrub steppe is the prevalent vegetation type in the Clark Canyon
Reservoir area. Big sagebrush and green rabbitbrush are common shrubs.
Rocky areas support mountain mahogany and broom snake weed. Perennial
bunch grasses such as bluebunch wheatgrass, fescue, and Indian
ricegrass occupy the understory alongside drought-adapted forbs.
    The proposed powerhouse site, at the base of Clark Canyon Dam, is
characterized by low to mid-height grasses and forbs.
    The proposed transmission line route would extend over 7.9 miles to
the south to the Peterson Flat substation. This area consists primarily
of basin big sagebrush and bluebunch wheatgrasss. Other vegetation
types found along the right-of-way (ROW) are Rocky Mountain juniper/
bluebunch wheatgrass woodland, quackgrass herbaceous vegetation, and
wetland areas along the two small creeks west of the reservoir.
Hayfields occur at the western end of the proposed transmission line
ROW.
    The Montana Natural Heritage Program (Montana NHP) lists 93 plant
species within Beaverhead County that are species of concern or
potential species of concern. Eleven of these species are listed as
sensitive species by BLM. Five of these plant species occur near the
project: bitterroot milkvetch, scallop-leaf lousewort (at high risk of
extirpation in Montana), hoary phacilia (a BLM watch species), chicken
sage, and limestone larkspur. The known populations of bitterroot
milkvetch, chicken sage, limestone larkspur, and hoary phacilia are
located outside of the area that would be affected by the project. The
scallop-leaf lousewort, which is known to occur in wetland and river
bottom areas, is located along the Beaverhead River riparian zone
downstream of Clark Canyon Dam.
Wetlands
    Wetlands are transitional land areas between terrestrial and
aquatic systems where the water table is usually at or near the land
surface or the land is covered by shallow water.
    The Beaverhead River at the base of the dam consists of a mix of
open water and emergent and shrub-scrub wetland habitats. A narrow
riparian corridor with a diversity of wetland plants along the river
bottom land borders the Beaverhead River downstream of Clark Canyon
Dam. Common riparian species include Baltic rush, hardstem bulrush, and
coyote willow. Immediately downstream of the tailrace and along the
original river channel, seepage has created a marsh wetland adjacent to
the Beaverhead River.
    Wetlands within the bottomlands of Horse Prairie Creek and Medicine
Lodge Creek along the transmission line ROW are dominated by cultivated
grasses such as quack grass, Kentucky bluegrass, and redtop, as well as
native species such as Baltic rush, sedges, and cattail. Coyote willow
was also present in the Horse Prairie Creek bottomland wetlands.
Wildlife
    The marsh wetland and riparian areas provide feeding and nesting
habitat for gulls, cormorants, sandhill cranes, and waterfowl. The open
water of Clark Canyon Reservoir and the Beaverhead River provide
feeding areas for waterfowl, bald eagles, and osprey, as well as
breeding habitat for amphibians. Mule deer, moose, pronghorn antelope,
and elk occasionally use the riparian meadows along the river and are
commonly found in the upland sagebrush steppe. Song birds nest and feed
in these habitats. The upland steppe provides feeding, breeding, and
nesting habitat for songbirds, game birds such as sage grouse, and
raptors such as ferruginous hawk.
    Common big game mammals in the area include mule deer, white-tailed
deer, elk, pronghorn, moose, and black bear. Mule deer comprise most of
the big game take in management districts of Montana DFWP Region 3,
which includes the project area. Pronghorn and mule deer also feed and
rear young in sage steppe habitats. Upland game birds popular with
hunters in the region include blue grouse and sage grouse. Other upland
game birds include chuckar, ruffed grouse, spruce grouse, Hungarian
partridge, pheasant, and sharp tailed grouse.
    Several furbearing mammals that occur in the region include coyote,
beaver, mountain lion, bobcat, wolverine, otter, marten, skunk, weasel,
mink, muskrat, raccoon, badger, and fox. Many of these species are
highly mobile, with large home ranges incorporating many habitat types.
Mink and muskrat and rodents such as voles may den along the banks of
the tailrace and meadow habitats. Others such as beaver, muskrat, and
otter are more restricted to the riparian corridor.
    The ferruginous hawk is a BLM special status species, a Montana
DFWP S2 species of concern (SOC), and is considered at risk for
extirpation from the state by Montana NHP. In Montana, ferruginous
hawks breed in the shortgrass foothills and steppe-habitat east of the
Rocky Mountains. These hawks commonly migrate south in the fall.
Ferruginous hawks are found on semi-arid plains and in arid steppe
habitats and prefer relatively unbroken terrain. In Montana they
inhabit shrub steppe and shortgrass prairie. Ferruginous hawks prefer
tall trees for nesting, but will use a variety of structures including
mounds, short cliffs, cutbacks, low hills, haystacks, and human
structures. Ferruginous hawks feed on ground squirrels, rabbits, pocket
gophers, kangaroo rats, mice, voles, lizards, and snakes. Populations
can be adversely influenced by agricultural activities. The Montana NHP
has records of 14 nest locations in the vicinity of the proposed
transmission ROW; however, no breeding birds have been documented by
the Montana NHP database since 2000. Nonetheless, there is suitable
nesting habitat in the project vicinity, and breeding pairs may use the
area for foraging. Call (1978 in Travsky and Beauvais, 2005) identified
the breeding season of ferruginous hawks to be March 10-July 2 with
nest building taking place from 10-16 March; egg laying from 17 March-
1April; incubation from 21 March-21 May; hatching from 16 April-21 May;
and fledging from 4 June-2 July.
    Montana NHP has one local record of occurrence of a sagebrush
sparrow (S2 SOC in Montana and a BLM sensitive species) from a couple
of miles north of the proposed transmission ROW in 2002. Southwestern
Montana is near the northern extent of the species' breeding range, and
sagebrush sparrows are generally uncommon. Nonetheless, there is
abundant suitable habitat in the vicinity of the proposed transmission
ROW and sagebrush sparrows could be present in the area during the
breeding season.
    Trumpeter swans are a Montana S2 and BLM sensitive species that
utilize the Clark Canyon reservoir as migration stopover and winter
habitat. A great

blue heron (S3 SOC in Montana) rookery is known from the east side of
the reservoir, but was last observed active in 1999. The only wetland
habitats found within the transmission line ROW that could support
nesting, wintering, and migrating birds are associated with Horse
Prairie Creek, Medicine Lodge Creek, and the Beaverhead River.
    The pygmy rabbit, a BLM special status species and a Beaverhead
National Forest sensitive species, is found from the Great Basin region
north to extreme southwestern Montana. Isolated populations are known
from east central Washington and Oregon. The project is located within
the range of pygmy rabbits, but pygmy rabbits have not been documented
in the vicinity of the project. The Great Basin pocket mouse is another
BLM sensitive species and a S1 SOC for Montana FWP. Southwestern
Montana is near the northern extent of the species' range. Occupied
habitats in Montana are arid and sometimes sparsely vegetated. They
include grassland[hyphen]shrubland, stabilized sandhills, and other
landscapes with sandy soils where sagebrush cover exceeds 25 percent.
Elsewhere, they are also known to occur in pine woodlands,
juniper[hyphen]sagebrush scablands, shortgrass steppes, and shrublands.
They tend not to occur in heavily forested habitats. The Montana NHP
does not have records of occurrence near the project, but there are
known populations in Beaverhead County and suitable habitat nearby.
    Preble's shrew and Merriam's shrew, both S2 SOC in Montana, have
not been documented in the project area, but have been known to occur
in Beaverhead County and have suitable habitat that exists in the
project area. Similarly, Southwestern Montana is at the western edge of
the known range for the Dwarf shrew, another S2 SOC in Montana. It is
possible, but unlikely, that this species occurs in the project area.
    The bald eagle is a Montana DFWP S1 species. Bald eagles continue
to be protected at the federal level under the Bald and Golden Eagle
Protection Act of 1940 and the Migratory Bird Treaty Act. The State of
Montana also has regulations that protect bald eagles. The 1994 Montana
Bald Eagle Management Plan developed by the Montana Bald Eagle Working
Group, and their addendum, the 2010 Bald Eagle Management Guidelines,
detail restrictions on human activities near known nest sites. Bald
eagles are found primarily near coastlines, rivers, reservoirs, and
lakes. Eagles principally eat fish, but also feed on carrion,
waterfowl, and small mammals. They use large trees as nest sites and
hunting perches. Eagles winter throughout much of the United States;
both wintering and nesting eagles can be found in the project vicinity.
    Bald eagles are known to nest near the proposed transmission line
ROW and downstream of Clark Canyon Dam. The Montana NHP has one record
of a bald eagle nest attempt in 2011 about 334 feet north of the
proposed project transmission ROW in the Horse Prairie Creek drainage,
west of the reservoir and a pair of eagles were observed at the nest
tree in February 2012. Montana DFW assumes the territory to be occupied
yearly. Bald eagle nests also have been observed downstream of the dam,
one of which was last documented in 2014. Bald eagles also utilize the
Clark Canyon Reservoir area in winter and during migration.
    The golden eagle is a BLM sensitive species, a Montana DFWP S2 SOC,
and a FWS Bird of Conservation Concern that is protected under the
federal Bald and Golden Eagle Protection Act. They are common year
round in open rangelands and mountainous habitats throughout Montana.
Golden eagles prey primarily on small mammals, particularly rabbits and
ground squirrels, but are also known to eat a wide variety of prey,
including birds, snakes, insects, and carrion. They usually nest in
large trees or on cliffs. Since the year 2000, there are no records of
active breeding territories for golden eagles within 0.5 mile of the
proposed project. However, the Clark Canyon Reservoir area does provide
suitable nesting and wintering habitat, and golden eagles may be
present at any time of year.
    On September 22, 2015, FWS determined that the greater sage-grouse
does not warrant protection under the ESA. A landmark landscape-scale
conservation initiative was started with conservation partnerships
instituted between federal and state governments, private land owners,
and others that provided sufficient protections to prevent listing
(FWS, 2015). However, the greater sage-grouse remains a Montana DFWP S1
SOC and a BLM sensitive species. It is the largest grouse species in
North America and a sagebrush[hyphen]obligate, depending on sagebrush
communities for breeding, nesting, brood[hyphen]rearing, and winter
habitat. Seasonal habitat characteristics vary considerably and greater
sage-grouse frequently move over large areas annually to meet their
seasonal needs. Populations are found scattered throughout Montana,
excluding the northwest and extreme northeast portions of the state.
Greater sage-grouse leks generally occur in open areas with sparse
shrub cover, while nests are usually located under sagebrush.
Brood[hyphen]rearing habitat tends to have higher cover of herbaceous
vegetation and abundant insects, which are an important food resource
for juveniles. Greater sage-grouse move to more mesic habitats as
herbaceous vegetation dries out and late summer brood[hyphen]rearing
habitats become more variable.
    In winter, greater sage-grouse feed almost exclusively on
sagebrush, which they also rely on for thermal and escape cover. Winter
habitat is often in areas with moderate cover of tall sagebrush that
emerges at least 10 to 12 inches from snow cover. Predators of adults
and juveniles include hawks, eagles, ravens, weasels, coyotes, and
foxes. Common nest predators include ground squirrels, badgers,
coyotes, ravens, and snakes. Predation can cause low rates of nest
success and juvenile survival.
    The greater sage-grouse population within the project area is
designated as part of the Southwest Montana Population, which occurs in
Madison and Beaverhead Counties. FWS developed a report titled Greater
Sage-grouse Conservation Objectives: Final Report (FWS, 2013). The FWS
(2013) considers the Southwest Montana population populations, which
includes Madison and Beaverhead Counties, to be at a low level of risk
considering the population size, limited habitat threats, and ties to
Idaho's birds. The proposed transmission ROW runs alongside Highway 324
and through the Montana DFWP-designated greater sage-grouse core area
identified as ``Beaverhead 3.'' Active and historic leks are known to
exist within four miles of the highway.
    As of 2012, greater sage-grouse had not been observed close to
Highway 324 and the proposed transmission ROW; however, they may
utilize the area during the late brooding season, when food resources
become scarce in more xeric habitats, or during migration to and from
breeding grounds. Any movement between breeding grounds in the Horse
Prairie and Medicine Lodge drainages would entail crossing the highway
and proposed transmission ROW. Movement to and from breeding grounds in
Montana and wintering areas in Idaho would also entail crossing through
the project area.
<IP_ADDRESS> Environmental Effects
Vegetation and Wetlands
    Approximately 0.10 acres of upland habitat near the dam would be
permanently converted for project features: 0.07 acres for the
powerhouse

and 0.03 acres for the substation. A staging area of approximately
8,000 square feet located adjacent to the access road would be used to
store materials, equipment, and fuels during the construction period. A
200 square foot area located near the east end of the downstream side
of the dam would be designated for the temporary containment of spoils
until it is either used as backfill or permanently removed from the
project site. The existing access roads would be improved for use
during project construction, operation, and maintenance. Vegetation
would be temporarily removed from this area until vegetation is re-
established following construction.
    The proposed access road currently appears to be little more than
an infrequently used track through perennial grasses and sagebrush
steppe vegetation. The increase in traffic associated with the project,
including heavy construction vehicle traffic, would likely cause soil
compaction and remove the existing perennial grasses from the roadway.
The increase in traffic during construction would temporarily disturb
wildlife in the vicinity of the road.
    The buried transmission line segment between the powerhouse and
powerhouse substation would roughly follow the south and east side of
the access road for about 0.3 mile. Transmission line construction
would require excavation of a 3-foot-wide by 3-foot-deep trench,
placement of conductor, and backfilling. The applicant states that
removed material would likely be temporarily placed alongside the
trench and would be replaced in the trench following placement of the
conductor. The buried transmission line would temporarily disturb about
8,000 square feet of perennial grasses and sagebrush steppe vegetation.
    Approximately five miles of the 7.9-mile long transmission line
would be located 100 to 200 feet north of Highway 324. The westernmost
two miles and several shorter sections (generally at road curves) would
be located closer to the highway. The proposed ROW would be 80 feet
wide. The applicant proposes to construct the transmission line as
single pole structures with an average span distance of 428 feet
between the poles. Clark Canyon Hydro estimates that 13 poles would be
required per mile and that each pole would displace approximately three
square feet of vegetation and temporarily disturb an additional 22
square feet. Less than 0.01 ac of vegetation would be permanently
removed to construct the proposed transmission line and approximately
0.05 acre could be temporarily disturbed by construction activities. No
trees would be removed within the proposed ROW.
    Construction activities, including pole placement for the
transmission line, would avoid wetlands to the extent practicable. The
wetland areas adjacent to the original river channel, tailrace channel,
and along the river would be protected from adverse construction
effects by avoidance and the installation of a silt fence to prevent
sediments from reaching the wetland areas.
    The applicant proposes to implement its Vegetation Management Plan
(VMP) to minimize effects to wetland, riparian, and upland vegetation.
The plan also includes measure to control noxious weeds. The VMP
includes the following best management practices to minimize vegetation
disturbance and loss and promote quick recovery of disturbed areas:
     Avoid driving off designated access routes whenever
possible, use existing developed and primitive roads;
     Clearly mark wetland/riparian areas with signs and/or
highly visible flagging during construction;
     Do not drive equipment, or stage materials in wetland/
riparian areas;
     Limit ground disturbance and grading to where absolutely
necessary;
     Educate equipment operators through: Review of this plan;
explicit delineation of all sensitive areas (e.g. wetland areas); the
presence of an on-site construction supervisor trained in environmental
protection; and frequent site walks to confirm all equipment operators
are familiar with the location of sensitive areas;
     Visually inspect of all construction and disturbance areas
a minimum of every seven days throughout the entirety of construction
activity;
     Minimize compaction by heavy equipment in previously
undisturbed off-road areas;
     Do not temporarily or permanently place fill material
within the channel in the delineated wetland area, unless specifically
permitted as part of the project design;
     Install biodegradable erosion control logs as needed
(e.g., every 200 feet) in any sloped areas to minimize erosion until
vegetation has established;
     Place biodegradable erosion control mats (coir fabric) on
slopes exceeding 5% (e.g. along the transmission line right-of-way, or
on the dam face) as needed to minimize erosion until vegetation has
established;
     Employ silt fence as needed if working during rain events
that may cause excess sediment to be washed into the Beaverhead River,
or into wetland areas; and
     Reclaim and revegetate temporarily disturbed areas as soon
as practicable after construction.
    The VMP also includes the following revegetation measures, which
would be applied to all construction areas on and below the dam, the
staging and spoil areas, temporary vehicle use and parking areas, and
areas temporarily disturbed by installation of the transmission line
poles:
     Preserving existing topography wherever possible;
     Following construction, ripping to a depth of 6 inches any
soils compacted by construction equipment;
     Removing noxious weeds around areas to be reseeded;
     Reseeding or replanting all disturbed soils using a mix of
native plants that meets Reclamation and BLM requirements; and
     Spreading certified weed-free mulch over seeded areas to
retain moisture and protect from soil erosion.
    The applicant proposes to use native topsoil for all revegetation
efforts. However, if this is not possible (e.g. if revegetation needs
to occur in an area that was excavated and re-filled), then topsoil
stripping and stockpiling would need to occur to ensure a proper
topsoil seed bed. Fertilizer would not be used during the initial
plantings. The species selected for planting would be adapted to
conditions at the site. Seeding would occur ideally in spring, early
summer (June-early July), or fall, within three months of construction.
    The applicant also proposes measures to treat and prevent the
spread of invasive weeds in the project area. Gravel and fill material
would be obtained from inspected and certified weed-free sources, and
all equipment would be cleaned and inspected prior to arrival at the
project area. Invasive weeds found prior to construction would be
flagged and treated manually (for small infestations), and larger
infestations would be treated with herbicides by an applicator
certified by the Montana Department of Agriculture. Flagging would
remain in place to designate the site as an area where additional weed
precautions must be taken. Access roads leading to construction areas
would also be inspected and weeds would be treated to preclude their
spread by equipment moving through the area.
    Under the proposed VMP, the applicant would monitor the
revegetation and invasive weed control efforts for a minimum of three
years post-construction, and until the

following performance standards are achieved:
     Vegetation cover would be comparable to conditions in the
adjacent, undisturbed reference area (within 70 percent of adjacent
cover) within five years of revegetation.
     Soil stability would be evident based on the absence of
rills, sediment fans, and other indicators of soil movement.
    The applicant would provide annual monitoring reports to
Reclamation and BLM by December 31 of each year. The reports would
include at a minimum:
     Description of each monitoring location including
vegetation cover, species composition, condition, and any evidence of
soil erosion;
     Discussion comparing revegetated versus reference plots
with regards to performance criteria;
     Declaration of any performance criteria that have been met
and a description of the progress made toward reaching any criteria
that are not yet attained; and
     Maintenance recommendations to be implemented to achieve
performance criteria.
Our Analysis
    The measures identified in the proposed VMP, if properly
implemented, would minimize adverse effects of vegetation loss and
disturbance and minimize the potential introduction and spread of
invasive weeds. Wetlands adjacent to the original river channel,
tailrace channel, along the river, and within the transmission line ROW
would be protected from negative construction effects by avoidance and
the installation of a silt fence to prevent sediments from reaching the
wetland areas.
    There would be a loss of perennial grassland habitat during the
construction period. Because the applicant would reseed this area with
native grass species from the area, this impact would be temporary.
Using certified weed-free mulch, as well as removing invasive weeds
from the areas to be revegetated, would aid in the success of these
mitigation efforts.
    Revegetation with native species, and using biodegradable erosion
control mats and logs until these efforts are established would prevent
revegetation material, such as seed and mulch, from being released into
wetlands or the river. Post-construction stabilization and effective
site restoration with native plants would minimize long-term effects on
environmental resources.
Wildlife
    Constructing the project would mostly be in an area already
disturbed by construction and operation of Reclamation's facilities.
The project transmission line may pose an electrocution risk to
perching birds and a collision risk to birds in flight. Raptors are at
risk of electrocution due to their use of power line poles as perching
structures. Species that are less maneuverable such as cranes,
pelicans, and large waterfowl are also susceptible to power line
collision. Birds that fly fast and low, such as geese, ducks, and
smaller flocking birds, are also at higher risk. Lines that pose a high
risk of collision include those over water, those that cross draws or
other natural flyways, and those placed immediately above tree tops and
ridgelines. Transmission lines that bisect areas of high bird movement,
such as lines placed between nesting and feeding habitats, also pose a
collision risk. The Montana DFWP identified three segments of the
proposed transmission right-of-way where bird activity is concentrated
and relatively high, including the portions within the Beaverhead River
corridor and where the lines cross Horse Prairie and Medicine Lodge
creeks.
    The applicant proposes to conduct pre-construction raptor surveys
within the transmission line ROW and coordinate with FWS, BLM, and
Montana DFWP on nest locations and nesting activity prior to and during
construction. Based on the survey results and agency consultation, the
applicant would incorporate any recommended construction buffers or
seasonal constraints to protect raptors. The applicant would construct
the transmission line in accordance with Avian Power Line Interaction
Committee (APLIC) standards \24\ and include visual markers on the
wires to prevent collisions as outlined in Reducing Avian Collisions
with Power Lines: The State of the Art in 2012 (APLIC, 2012). In
addition, the applicant proposes to coordinate with relevant agencies
involved in greater sage-grouse management in southwest Montana,
including Montana DFWP, the Montana Sage-Grouse Habitat Conservation
Manager within the Montana Department of Natural Resources and
Conservation (Montana DNRC), BLM, and FWS. As practicable, the
transmission towers would also include perch deterrents to reduce or
eliminate use by avian predators for nesting and perching on the
transmission line infrastructure. The applicant also proposes that any
recommended buffers seasonal constraints related to avian protection
would be incorporated into the project design.
---------------------------------------------------------------------------

    \24\ In their reply comments, Clark Canyon Hydro, LLC explicitly
stated their intent to use APLIC's Suggested Practices for Avian
Protection on Power Lines: The State of the Art in 2006 (APLIC,
2006), which are the most current guidelines to date for
transmission line construction (Clark Canyon Hydro, LLC, 2016).
---------------------------------------------------------------------------

    In their letter filed March 17, 2016, Interior recommended that to
the maximum extent practicable, project construction shall be scheduled
so as not to disrupt nesting raptors or other birds during the breeding
season. This includes a 0.5-mile no construction buffer during the
breeding season (species-specific) for most nesting raptor species,
including ferruginous hawks that nest in the project area. If work is
proposed to take place during the breeding season or at any other time
which may result in take of migratory birds, their eggs, or active
nests, the licensee shall take all practicable measures to avoid and
minimize take, such as maintaining adequate buffers, to protect the
birds until the young have fledged. Active nests may not be removed. If
field surveys for nesting birds are conducted with the intent of
avoiding take during construction, any documentation of the presence of
migratory birds, eggs, and active nests, along with information
regarding the qualifications of the biologist(s) performing the
surveys, and any avoidance measures implemented at the project site
shall be maintained
    In addition, they recommended that if any active bald eagle nests
occur within 0.5 mile of the project during construction, the licensee
shall comply with the temporary seasonal disturbance restrictions
(generally February 1-August 15) and distance buffer (0.5 mile)
specified in the 2010 Montana Bald Eagle Management Guidelines: An
Addendum to Montana Bald Eagle Management Plan (Montana Bald Eagle
Working Group, 2010) during construction. To minimize the electrocution
and collision hazard to eagles in the project area, the licensee shall
ensure that: (1) Any newly constructed power lines or substations
adhere to the APLIC standards in Suggested Practices for Avian
Protection on Power Lines: The State of the Art in 2006; and, (2) all
new power lines shall include visual markers on the wires to prevent
collisions per techniques outlined in Reducing Avian Collisions with
Power Lines: The State of the Art in 2012. In its reply comments, the
applicant reiterated its proposed environmental measures, as mentioned
previously.

    In addition, Interior recommended that the applicant coordinate
with Montana DNRC and BLM regarding compliance with the Montana
Executive Order 12-2015 and the Idaho Southwestern Montana Greater
Sage-Grouse Land Use Plan Amendment, where applicable. Interior also
recommended that the applicant provide compensatory mitigation to
offset any unavoidable effects that remain after implementing avoidance
and minimization measures for greater sage-grouse. In its reply
comments, the applicant stated that no effects to greater sage-grouse
were anticipated, and did not expect compensatory mitigation to be
required after implementation if its proposed avoidance and mitigation
measures.
Our Analysis
    Project construction would temporarily disturb and displace
wildlife in the immediate vicinity of construction activities. The
population of ferruginous hawks in the vicinity may use the area of the
access road and transmission line ROW for foraging. This activity would
be unavoidably but temporarily lost during the construction period.
    Because most construction would occur in areas disturbed from
constructing and operating Reclamation's dam, the greatest potential
for disturbing and displacing nesting birds would be during
construction of the transmission line. Highway 324 already fragments
wildlife habitat. Locating the transmission line within the road ROW
would minimize further habitat losses, but it would also add a new
vertical dimension to that fragmentation. Conducting pre-construction
raptor nest surveys in coordination with FWS, BLM, and Montana DFWP
would identify any raptor nests that might be disturbed during
construction of the project. Disturbance and displacement of nesting
raptors would be avoided if construction activities are scheduled to
avoid the nesting period or through the use of 0.5-mile construction
buffer as recommended by Interior and agreed to by the applicant.
However, because the nesting period for the ferruginous hawks (March
10-July 2) and the seasonal disturbance restrictions (generally
February 1-August 15) and distance buffers (0.5 mile) for the bald
eagle overlap significantly with the available construction season,
implementing these construction limits could significantly delay
construction, particular for the transmission line.
    Therefore, avoidance of the entire breeding season for all birds
may not be practicable. Maintaining records of the pre-construction
survey results and the measures taken to avoid disturbing nesting
raptors and birds during construction would allow the applicant to
document its efforts to minimize and avoid adverse effects on migratory
birds. Those records should include the reproductive status of any
identified nests, qualifications of the surveyor, and the applicant's
proposed avoidance measures.
    The applicant's proposal to adhere to APLIC guidance in the design
and construction of the transmission line, including installing flight
diverters and perch deterrents to prevent perching, would reduce the
risk of avian collision and electrocution, as well as predation of sage
grouse.
    Greater sage grouse may abandon leks if repeatedly disturbed by
raptors perching on power lines or other tall vertical structures near
leks (Ellis 1984), by vehicular traffic on roads (Lyon and Anderson
2003), or by noise and human activity associated with energy
development (Braun et al. 2002; Holloran 2005; Kaiser 2006). Indirect
effects could also occur from habitat degradation. Because the project
would be constructed in habitats that have already been disturbed and
subject to frequent human use (e.g., construction and operation of
Reclamation's dam and Highway 324), greater sage grouse habitat in the
project area is considered poor and any degradation of habitat
conditions from project construction minimal. Reestablishing native
vegetation and controlling invasive weeds through the VMP would further
minimize any adverse effects on sage grouse habitat.
    Because the project would be co-located with existing development,
it is unlikely that any greater sage grouse leks or breeding habitat
occur near any project facility, except possibly where the proposed
transmission line crosses Horse Prairie and Medicine Lodge drainages.
Scheduling construction of these segments of the transmission line
outside of the greater sage grouse breeding season would avoid
disturbing sage grouse. The breeding season for greater sage-grouse is
highly dependent on elevation and the length of winter conditions, and
leks occurring in higher elevations may continue through early to mid-
May (Connelly et al., 2003). In southeast Montana the breeding season
is from March 1- April 15 and nesting and brood-rearing occurs between
April 16-July 15 (Montana DFWP and BLM, undated). In the Montana DFWP
and BLM study, nests were located at an average elevation of 3,442
feet, which is lower than the elevation of the proposed project. As
such, the breeding season for the greater sage-grouse in the project
area may be later in the spring, or early summer. This could delay
construction of these segments of the transmission line until mid- to
late-summer, but would not affect the post-construction revegetation
effort, as the VMP states that the revegetation efforts may be carried
out in the fall. The VMP also states that seeding should not occur
during hot, dry, summer conditions (late July through August), or after
if there is a significant amount of snow on the ground. Including
seasonal restrictions on transmission line construction would still
allow time for the transmission line to be constructed and the
revegetation mitigation to take place before weather conditions become
unfavorable. The avoidance and mitigation measures proposed by the
applicant, as well as constructing segments of the transmission line
outside of the breeding season, would ensure that the project would
have minimal effects on the greater sage-grouse.

3.3.4 Threatened and Endangered Species

<IP_ADDRESS> Affected Environment
    Commission staff accessed the IPaC Web site on April 15, 2016, and
generated the following list of threatened and endangered species with
the potential to occur in the vicinity of the project: the threatened
plant Ute ladies'-tresses (ULT), threatened grizzly bear, and the
threatened Canada lynx. There are no critical habitats present in or
around the project area.
Ute Ladies'-Tresses
    ULT was listed as threatened under the ESA on January 17, 1992 (50
CFR part 17, Vol. 57, No. 12). Clark Canyon Hydro conducted a survey
for ULT in 2007 and 2011 in support of application for prior
proceedings. No UTL were found and no suitable habitat was found within
the areas that would be subject to disturbance from project
construction and operation (ERM, 2015).
Grizzly Bear
    FWS listed the grizzly bear as threatened on July 28, 1975. Grizzly
bears are normally solitary, except during breeding season or when
caring for cubs. Home ranges for individual bears vary depending on
food availability, weather conditions, other bears, and season. Female
bears need large home ranges to support their offspring. Grizzly bears
are opportunistic in their eating habits and will feed on prey items
like small mammals or fish, but will also forage for

plants, berries, roots, and fungi. They will also scavenge on carrion
and garbage. They prefer habitats with significant forest cover,
especially for beds (FWS, 1993). This habitat is not present in the
project area, and the project area is outside of its historical range
and present distribution (FWS, 1993); therefore, grizzly bears are not
expected to occur in the project site.
Canada Lynx
    Canada lynx are medium-sized cats that inhabit boreal forests and
feed almost exclusively on snowshoe hare. The United States, primarily
the Northeast, western Great Lakes, northern and southern Rockies, and
northern Cascades, is the southern-most extent of its range.
Populations of snowshoe hare have a direct effect on local lynx
populations, which fluctuate in response to its prey. In the United
States, Canada lynx prefer conifer-hardwood forests that support
snowshoe hare. The Canada lynx was listed under the ESA as threatened
on March 24, 2000 (FWS, 2005). The Canada lynx is not expected to occur
at the project site due to the lack of habitat.
<IP_ADDRESS> Environmental Effects
    No effects to threatened or endangered species are anticipated as a
result of project construction and operation. ULT was not found during
surveys in the project area in 2007 or 2011. Although the proposed
transmission line route has a slightly different alignment than
surveyed in 2011, surveys covered habitats that might support the
species such as Medicine Lodge Creek, Horse Prairie Creek, and the
wetlands near Beaverhead Creek below the dam.
    With respect to grizzly bears and Canada lynx, the project area
does not contain suitable habitat for either species. Suitable habitat
for the snowshoe hare, the primary prey species for Canada lynx, is
also not available in the project area. Therefore, constructing and
operating the project would have no effect on Ute ladies'-tresses,
grizzly bears or Canada lynx, and no further action is warranted.

3.3.5 Recreation, Land Use, and Aesthetics

<IP_ADDRESS> Affected Environment
Recreation
    Reclamation manages approximately 15 recreation sites at Clark
Canyon Reservoir and just downstream of the dam (figure 11). The sites
include fishing access, campgrounds, day-use areas, boat ramps, and an
overlook. Recreational opportunities at the reservoir include boating,
visiting cultural/historic sites, camping, fishing, hiking, hunting,
picnicking, water sports, wildlife viewing, and using recreational
vehicles. According to Reclamation's Great Plains Region Clark Canyon
Web site (Reclamation, 2016), the reservoir, at full pool, has 4,935
surface acres and 17 miles of shoreline offering good fishing for
rainbow and brown trout. There are several concrete boat ramps, picnic
shelters, and a marina, along with 9 campgrounds, including one
recreational vehicle-only site, for a total of 96 campsites. The
Cattail Marsh Nature Trail offers wildlife watching opportunities for
seasonal waterfowl. Montana DFWP also manages several fishing access
areas (figure 11) on the Beaverhead River downstream of the dam that
are used by wading and bank anglers as well as by anglers on both
guided and unguided float trips (Montana DFWP, 2003). In a letter filed
September 19, 2007, during review of the prior license application, the
Park Service stated that the Montana DFWP-managed Henneberry fishing
access is an L&WCF site. The site is about 5 miles downstream of the
proposed project (figure 11).
    As noted in section <IP_ADDRESS>, the Beaverhead River is recognized as
one of the most popular and productive trout fisheries in North
America, and is designated as a blue ribbon fishery by Montana DFWP.
Brown and rainbow trout are well established, and often attain trophy
size in the Beaverhead River. Recreational use of the reservoir is also
quite high, with heavy use from personal watercraft, water-skiers and
pleasure boaters, as well as from anglers due to the high quality of
the fishing.
    Of the recreational sites at the reservoir and immediately
downstream of the dam (figure 11), those closest to the proposed
project area include Beaverhead Campground (17.08 acres), Buffalo
Bridge fishing access area, High Bridge fishing access area (0.18
acres), and Clark Canyon Dam fishing access area (also known as
Beaverhead River fishing access area, 3.27 acres). Use figures from a
2004 recreation survey of the area indicated that the Beaverhead
Campground and Beaverhead River fishing access area are frequently used
by campers (10,423 visitors per year) and anglers (3,042 visitors per
year), respectively (Dvorak et al., 2004). The survey did not include
the Buffalo Bridge or High Bridge fishing access areas. Traffic count
data from Reclamation for 2007 and 2008 indicated that more than 75
percent of the vehicle use of the Clark Canyon Dam and Buffalo Bridge
fishing access areas occurred from March through October (email from
Steve Davies, Reclamation, to FERC staff, filed on March 25, 2009).
During those two years, the greatest use at Clark Canyon Dam fishing
access area occurred in June (781 vehicles in 2007 and 789 in 2008). At
Buffalo Bridge fishing access area, the greatest use occurred in June
(728 vehicles in 2008) or July (647 vehicles in 2007). Reclamation did
not have traffic count data for the High Bridge fishing access area,
which is managed by Montana DFWP.
    In 2009, the Beaverhead River had 38,706 angler days in 2009
(Montana DFWP, 2015). Fishing regulations are in place to help manage
heavy use, and fishing closures have occurred in drought years.
BILLING CODE 6717-01-P

[GRAPHIC] [TIFF OMITTED] TN29JN16.011

BILLING CODE 6717-01-C

Land Use
    The proposed project, including most of the transmission line
corridor, would occupy 62.1 acres of federal lands within the Pick-
Sloan Missouri Basin Program, East Bench Unit, administered by
Reclamation. It would also occupy 0.2 acres of federal land
administered by BLM. In addition to substantial recreation
opportunities, the dam and reservoir provide for irrigation and flood
control across a wide area downstream of the project.
Aesthetics
    The Clark Canyon Dam and Reservoir present a relatively natural
appearance in a broad, open valley of scenic, rolling landscape, with
low vegetation cover of grasses and shrubs with a few patches of
taller, thicker vegetation. The dam and reservoir are dominant
landscape features that are quite visible to motorists traveling on
Interstate Highway 15 (I-15) and very visible from adjacent lands.
Dominant features include the dam structure, the reservoir, Armstead
Island (see figure 11), and several recreation facilities. Wildlife
viewing areas include a developed bird watching trail, as well as the
delta areas near the mouths of Horse Prairie Creek and Red Rock River
(see figure 1). A 3.2-mile-long section of the Beaverhead River between
the I-15 bridge at Pipe Organ Rock and the Dalys highway exit has been
evaluated for eligibility for ``Recreation'' classification of the Wild
and Scenic River Act and is considered ``outstandingly remarkable'' for
recreation, fish and historic values (BLM, 2005). This section of the
river starts about 6 miles downstream of the project area.
    Several transmission lines are present in the vicinity of the
project; however, transmission lines are absent along approximately
five miles of Montana Highway 324, north and west of the Clark Canyon
Reservoir. The proposed new transmission line would parallel this
portion of the highway.
<IP_ADDRESS> Environmental Effects
Recreation
    Issues that have been identified with respect to recreation apply
primarily to the year-long construction period. Construction equipment
activity could generate temporary disturbance to recreational use,
including noise and dust, which could diminish the quality of the
recreation experience in the vicinity of the proposed project,
particularly at the Clark Canyon Dam/Beaverhead River fishing access
site (figure 11). Additionally, there could be safety concerns where
recreational users and construction vehicles use the same roadways to
access areas near the dam. Construction access would use the Buffalo
Bridge approach and could affect fishing access to the river at that
location, although regular use of the road by construction vehicles is
not expected.
    To reduce effects on fishing access, the applicant proposes to
implement its Buffalo Bridge Fishing Access Road Management Plan. The
plan provides for alerting the public to potential traffic hazards
during construction and specifies the contents of a public notice,
locations for posting, the number, type, and locations of any barriers
that would be installed, a process to evaluate effectiveness of the
plan and modify the plan if needed, and an implementation schedule.
Flagging, traffic control devices, and signs would be used to further
reduce effects on traffic and traffic safety. During project operation,
minor noise and nighttime security light from the powerhouse could be
noticeable to recreational users nearby.
    To minimize the effects of construction activities on nearby
recreation users, the applicant proposes to limit construction
activities in summer (Memorial Day through Labor Day) to daytime hours
(7:00 a.m. to 8:00 p.m.). The applicant also proposes to have no
construction taking place over peak summer holiday weekends (Memorial
Day, Independence Day, and Labor Day), including the day before and day
after those weekends. A sign with contact information would be posted
at a location approved by Reclamation and would provide dates and hours
of construction.
    The southbound exit ramp from I-15 to Montana Route 324 is proposed
as a secondary access route for construction vehicles. This route is
also an existing access route to the dam site and is gated to prevent
unauthorized access. Construction traffic on the secondary route may
affect exit ramp traffic.
    The applicant's proposal also includes installation and maintenance
of an interpretive sign near the dam to inform visitors of the concept
and function of the project, its relationship to aquatic resources and
the recreational fishery, and measures taken to reduce adverse effects.
The sign would be placed at a location acceptable to Reclamation.
Our Analysis
    During project construction, the applicant's proposed limits on
construction hours, days, and locations would reduce conflicts with
recreational users, and its proposed construction access routes and
vehicle staging would reduce potential conflicts with other motorists.
If public notices, signage, and barriers are used where appropriate,
and the Buffalo Bridge Fishing Access Road Management Plan is
implemented, this would further reduce potential concerns about traffic
safety and effects on fishing access.
    Secondary use of the I-5 exit ramp for construction vehicles would
have little effect on traffic or recreational use, including the two
nearest recreational sites, due to relatively light traffic and only
occasional use of the ramp and access route for construction. The
entrance to Beaverhead Campground is located at the top of Exit 44 on
Route 324, and the access to the Clark Canyon Dam/Beaverhead River
fishing access site is located on the opposite side of the river from
the construction access routes, which would minimize any potential
disturbance to recreation users in the areas that are nearest the
construction activity.
    During project operation, minor noise and light from the powerhouse
could be noticeable to recreational users nearby, particularly those
fishing or camping immediately below the dam, but the proximity of I-15
to both the project site and the nearby recreation sites suggests that
this effect would be minimal. All existing recreation sites would
remain accessible to the public during project operation.
    The applicant proposes to operate the project in run-of-release
mode, consistent with the current method of operation employed by
Reclamation. Run-of-release operation would maintain the existing water
surface elevations. Therefore, fishing and boating on the reservoir
would not be affected, and neither would fishing opportunities
downstream of the dam in the Beaverhead River be affected.
    With respect to the potential effects of the project on the
Henneberry Fishing Access, the applicant does not propose any project-
related activities that would result in water quantity or quality
effects at the site or interfere with access during construction or
operation. The site would continue to be available for recreational
use.
    The applicant's proposed interpretive sign would enhance the
recreational experience for users and would also assist the public in
understanding the project's potential effects on the prized fishery
(see section, <IP_ADDRESS>, Aquatic Resources).
Land Use
    Except for the footprint of the hydropower facilities and
transmission line, land uses and public access in the vicinity of the
project would remain

unchanged. Excluding the proposed transmission line, the project
footprint would be small (approximately 0.10 acres at the dam), and the
effect on land use would be minor.
Aesthetics
    Project construction activities would be visible from I-15, Highway
324, recreation sites below the dam, and from other sites near the dam
and along the transmission line corridor. Once construction is
complete, the permanent presence of above-ground facilities, including
the powerhouse, transformer, parking area, and transmission line would
alter the current visual environment.
    A major portion of the new overhead transmission line would be
located along approximately five miles of Montana Highway 324 west of
the Camp Fortunate Overlook, where no transmission line currently
exists. This could affect the aesthetic quality of nearby recreation
and cultural resources, including the Clark Canyon Reservoir, the Lewis
and Clark Trail, Camp Fortunate Overlook, several campgrounds, and a
day-use area that are located along this stretch of the highway and
above the shore of the reservoir.
    As part of its Visual Resources Management Plan (VRMP), the
applicant proposes to address short-term impacts by limiting
disturbance or displacement of vegetation to the extent possible. To
reduce long-term effects, the applicant proposes to bury a short, 0.3-
mile-long transmission line between the proposed powerhouse and
substation; use contouring and replanting to help the areas disturbed
by construction, including the transmission line corridor, blend with
the surrounding terrain; and consult with Reclamation on the design of
project features, including color and construction materials. The
applicant also states that it would use relevant comprehensive
management plans to ensure that all new features of the proposed
hydroelectric project meet established visual quality objectives.
    The applicant's VRMP, filed with the Commission on February 1,
2016, lists the following as basic design criteria:
     Prevention of adverse visual impacts, whenever possible,
by means of preconstruction planning and design, particularly in the
selection of facility locations;
     Reduction of adverse visual impacts that cannot be
completely prevented, by designing features with appearances consistent
with existing structures;
     Reduction of adverse visual impacts to existing vegetation
during construction by means of post-construction vegetation
rehabilitation; and
     Quality control during construction, operation, and
construction rehabilitation to ensure that the preceding objectives are
achieved.
    After license issuance but prior to the start of construction
activities, including any land-disturbing or land-clearing activities,
the VRMP calls for the applicant to file with the Commission a pre-
construction visual impact assessment of the project area. That
assessment would include photographs taken from three proposed key
observation points (the parking area at the Clark Canyon Dam/Beaverhead
River fishing access area, Highway 324 immediately above the power
house, and the secondary access point on I-15 north of Clark Canyon
Dam). The plan also includes the filing of post-construction
photographic assessments annually for the first three years of project
operation. If a license is issued for the project, the applicant would
consult with Reclamation during the design phase to identify
appropriate colors for structures on Reclamation lands and to identify
appropriate vegetation mixes for disturbed areas of the project.
Our Analysis
    As noted by the applicant, the proposed hydropower facility would
be designed to blend in with the existing dam structure as much as
possible. Implementation of the applicant's VRMP, including
consultation with Reclamation concerning structure color and
appropriate vegetation mixes, would minimize any long-term effect on
the aesthetic character of the project site.
    The previously altered landscape, including construction of the
existing dam and its appurtenant features is highly visible to people
using area roads and recreation sites. The proposed hydroelectric
facility would be generally out of view from areas above the dam, but
would be conspicuous below the dam. However, the proposed facilities
would not be inconsistent with the existing or associated landscape
features.
    The overhead portion of the transmission line would have a modest
effect on the visual character of the area west of the Camp Fortunate
Overlook, where no transmission line currently exists. Scenic and
cultural values in the vicinity are associated with the extensive
recreational amenities around the reservoir and near the highway.
However, the transmission line would be generally located on the uphill
side of the highway and away from the reservoir and recreation sites.
Much of the transmission line would be located 100 to 200 feet from the
highway, which would reduce its visibility to highway motorists and
recreation users on or near the reservoir. As described above, the use
of a single-pole design and unobtrusive materials and colors would
further reduce its visibility and would be consistent with the criteria
of VRMP. However, the transmission line was not specifically identified
as a project facility that would be addressed by the proposed VRMP.
While no additional measures are necessary, any deviation from the
proposed design could have more of a negative effect on the aesthetic
landscape. Applying the criteria and consultation procedures in the
VRMP to the transmission line would ensure that visual effects are kept
to a minimum.

3.3.6 Cultural Resources

<IP_ADDRESS> Affected Environment
    NHPA section 106 requires that the Commission evaluate the
potential effects on properties listed or eligible for listing in the
National Register. Such properties listed or eligible for listing in
the National Register are called historic properties. In this document,
we also use the term ``cultural resources'' for properties that have
not been evaluated for eligibility for listing in the National
Register. Cultural resources represent things, structures, places, or
archeological sites that can be either prehistoric or historic in
origin. In most cases, cultural resources less than 50 years old are
not considered historic. Section 106 also requires that the Commission
seek concurrence with the SHPO on any finding involving effects or no
effects to historic properties, and allow the Advisory Council on
Historic Preservation (Council) an opportunity to comment on any
finding of effects to historic properties. If Native American (i.e.,
aboriginal) properties have been identified, section 106 also requires
that the Commission consult with interested Indian tribes that might
attach religious or cultural significance to such properties. In this
case, the Commission must take into account whether any historic
property could be affected by a proposed new license within the
project's area of potential effect (APE), and allow the Council an
opportunity to comment prior to issuance of any new license for the
project.
Area of Potential Effect
    Pursuant to section 106, the Commission must take into account
whether any historic property could be affected by the issuance of a
proposed

new license within a project's APE. The APE is determined in
consultation with the SHPO and is defined as the geographic area or
areas within which an undertaking may directly or indirectly cause
alterations in the character or use of historic properties, if any such
properties exist.
    The APE includes all lands within the project boundary and
construction footprint, as well as the 7.9-mile-long, 80-feet-wide
transmission line corridor and a portion of the Clark Canyon Dam,
including the spillway. The APE is defined in the February 2016 HPMP.
In an amendment to the HPMP filed on March 11, 2016, the applicant
corrected the total area of the APE to 88.6 acres, including 68.3 acres
of federal land owned by Reclamation.
Cultural History Overview
    The immediate area within the vicinity of the proposed project was
an important prehistoric and historic travel route. During the
ethnographic period (pre-European contact), the Clark Canyon watershed
was occupied seasonally by the Lemhi-Shoshone Tribes. Lewis and Clark
were the first Euro-Americans to pass through the Beaverhead Valley on
August 13, 1805.
    The Lewis and Clark expedition made its first contact with
Sacagawea's Shoshone Tribe at a location that is currently inundated by
Clark Canyon Reservoir. The location was named ``Camp Fortunate'' due
to the hospitality of the tribe and its willingness to trade for
horses, a necessity for crossing the Rockies.\25\
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    \25\ The Lewis and Clark expedition crossed the Continental
Divide at Lemhi Pass on August 12, 1805. Approximately 208 acres in
the vicinity of Lemhi Pass, about 35 miles from the proposed project
site, are designated as a registered historic landmark by Interior.
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    In 1862, gold was discovered near the town of Bannock, Montana, and
caused the first wave of rapid Euro-American settlement in the area. At
the height of the area's gold rush, Bannock, about 175 miles from the
proposed project site, had a population of more than 3,000 and was the
first Montana territorial capital. The period was short lived, however,
and old mining camps and ghost towns are all that remain.
    In 1877, approximately 750 Nez Perce Native Americans fled north
out of Idaho because of the demands of the U.S. Army that they move
onto a reservation. On August 9, 1877, the U.S. Army attacked the Nez
Perce along the north fork of the Big Hole River, about 50 miles from
the proposed project site. Although the Battle of Big Hole lasted less
than 36 hours, significant casualties were suffered on both sides. In
1992, legislation incorporated Big Hole National Battlefield with the
Nez Perce National Historical Park.
    The city of Dillon, about 20 miles from the proposed project site,
originated during construction of the Utah and Northern Railroad. The
city was the site of a construction camp during the winter of 1880. The
railroad was pushing north toward Butte, but winter conditions halted
progress until the spring of 1881. When construction resumed in the
spring, the town remained. The city was named in honor of Sidney
Dillon, the president of the Union Pacific Railroad.
Prehistoric and Historic Archaeological Resources
    An archaeological survey of the applicant's cultural resources
inventory area for the prior license application identified one
prehistoric artifact, a single chert flake. As an isolated find, this
artifact does not meet the criteria for listing on the National
Register. No prehistoric or historic-era sites were documented at that
time.
    The project APE contains a single structure that is considered
eligible for listing on the National Register--Clark Canyon Dam. Clark
Canyon Dam (24BE1740) is an earthen dam constructed in 1964 by
Reclamation. This structure meets the 50-year age requirement for
listing on the National Register. Although the Clark Canyon Dam was
potentially eligible for listing on the National Register as a