[Federal Register Volume 71, Number 136 (Monday, July 17, 2006)]
[Proposed Rules]
[Pages 40587-40621]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 06-6182]



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Part II





Department of the Interior





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Fish and Wildlife Service



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50 CFR Part 17



Endangered and Threatened Wildlife and Plants; Designation of Critical 
Habitat for the Peck's Cave Amphipod, Comal Springs Dryopid Beetle, and 
Comal Springs Riffle Beetle; Proposed Rule

Federal Register / Vol. 71, No. 136 / Monday, July 17, 2006 / 
Proposed Rules

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AU75


Endangered and Threatened Wildlife and Plants; Designation of 
Critical Habitat for the Peck's Cave Amphipod, Comal Springs Dryopid 
Beetle, and Comal Springs Riffle Beetle

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to 
designate areas of occupied, spring-related aquatic habitat in Texas as 
critical habitat for the Peck's cave amphipod (Stygobromus pecki), 
Comal Springs dryopid beetle (Stygoparnus comalensis), and Comal 
Springs riffle beetle (Heterelmis comalensis) under the Endangered 
Species Act of 1973, as amended (Act). The three listed species are 
known only from four spring systems in central Texas: Comal Springs and 
Hueco Springs in Comal County, and Fern Bank Springs and San Marcos 
Springs in Hays County. The total area proposed as critical habitat for 
the amphipod is about 38.5 ac (acres) (15.6 hectares (ha)), for the 
dryopid beetle is about 39.5 ac (16.0 ha), and for the riffle beetle is 
approximately 30.3 ac (12.3 ha).

DATES: We will accept comments from all interested parties until 
September 15, 2006. We must receive requests for public hearings in 
writing at the address shown in the ADDRESSES section by August 31, 
2006.

ADDRESSES: If you wish to comment, you may submit your comments and 
materials concerning this proposal by any one of several methods:
    1. You may submit written comments and information by mail or hand-
delivery to Robert T. Pine, Supervisor, U.S. Fish and Wildlife Service, 
Austin Ecological Services Office, 10711 Burnet Road, Suite 200, 
Austin, Texas 78758.
    2. You may send your comments by electronic mail (e-mail) to 
[email protected]. Please see the Public Comments Solicited 
section below for file format and other information about electronic 
filing.
    3. You may fax your comments to 512/490-0974.
    4. You may submit comments via the Federal eRulemaking Portal: 
http://www.regulations.gov. Follow the instructions for submitting 
comments.
    Comments and materials received, as well as supporting 
documentation used in the preparation of this proposed rule, will be 
available for public inspection, by appointment, during normal business 
hours at the Austin Ecological Services Office at the above address.

FOR FURTHER INFORMATION CONTACT: Robert T. Pine, Supervisor, Austin 
Ecological Services Office (telephone 512/490-0057; facsimile 512/490-
0974).

SUPPLEMENTARY INFORMATION:

Public Comments Solicited

    We intend that any final action resulting from this proposal will 
be as accurate and as effective as possible. Therefore, we solicit 
comments or suggestions from the public, other concerned governmental 
agencies, the scientific community, industry, or any other interested 
party concerning this proposed rule. Comments particularly are sought 
concerning:
    (1) The reasons any habitat should or should not be determined to 
be critical habitat as provided by section 4 of the Act (16 U.S.C. 1531 
et seq.), including whether it is prudent to designate critical 
habitat;
    (2) Specific information on the distribution and abundance of 
Peck's cave amphipod, Comal Springs dryopid beetle, or Comal Springs 
riffle beetle and their habitats. Are there additional areas occupied 
at the time of listing that should be included in the designations and 
why? Are there areas that are not occupied but which are essential to 
the conservation of the species?;
    (3) Land use designations and current or planned activities in, or 
adjacent to, the subject areas and their possible impacts on proposed 
critical habitat;
    (4) Any foreseeable economic, national security, or other potential 
impacts resulting from the proposed designation and, in particular, any 
impacts on small entities;
    (5) Whether our approach to designating critical habitat could be 
improved or modified in any way to provide for greater public 
participation and understanding, or to assist us in accommodating 
public concerns and comments;
    (6) Are there data supporting the need for subsurface vegetation 
(e.g., roots that can penetrate into the aquifer) for sheltering, 
breeding, or feeding habitat for any or all of the listed 
invertebrates? If so, does the 50-foot (ft) distance appropriately 
define the lateral extent of critical habitat to provide for the PCEs 
related to the surface vegetation that produces the subsurface 
vegetation (e.g., roots)?;
    (7) Whether populations of Comal Springs riffle beetles may exist 
elsewhere in Spring Lake such as spring outlets;
    (8) Whether there are data supporting the premise that any or all 
of the beetles are detritivores (detritus-feeding animals) in spring-
influenced riparian zones;
    (9) Whether there are any data documenting the need of subsurface 
areas for breeding, feeding, or sheltering, or documenting the presence 
of any or all of the beetles in the subsurface areas; and
    (10) Whether the benefit of exclusion of any particular area 
outweighs the benefits of inclusion under section 4(b)(2) of the Act.
    If you wish to comment, you may submit your comments and materials 
concerning this proposal by any one of several methods (see ADDRESSES 
section above). Please submit e-mail comments to 
[email protected] in ASCII file format and avoid the use of 
special characters or any form of encryption. Please include ``Attn: 
Comal Springs invertebrates'' in your e-mail subject header and your 
name and return address in the body of your message. If you do not 
receive a confirmation from the system that we have received your e-
mail message, please contact us directly by calling our Austin 
Ecological Services Office at 512/490-0057. Please note that the e-mail 
address, [email protected], will be closed at the termination of 
the public comment period.
    Our practice is to make comments, including names and home 
addresses of respondents, available for public review during regular 
business hours. We will not consider anonymous comments, and we will 
make all comments available for public inspection in their entirety. 
Comments and materials received will be available for public 
inspection, by appointment, during normal business hours at the above 
address.

Role of Critical Habitat in Actual Practice of Administering and 
Implementing the Act

    Attention to, and protection of, habitat can be essential to 
successful conservation actions. The role that designation of critical 
habitat plays in protecting habitat of listed species, however, is 
often misunderstood. As discussed in more detail below in the 
discussion of exclusions under section 4(b)(2) of the Act, there are 
significant limitations on the regulatory effect of designation under 
section 7(a)(2) of the Act. In brief, (1) designation provides 
additional protection to habitat only where there is a Federal nexus; 
(2) the protection is relevant only when, in the absence of 
designation, destruction or adverse modification of the critical

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habitat would in fact take place (in other words, other statutory or 
regulatory protections, policies, or other factors relevant to agency 
decision-making would not prevent the destruction or adverse 
modification); and (3) designation of critical habitat triggers the 
prohibition of destruction or adverse modification of that habitat, but 
it does not require specific actions to restore or improve habitat.
    Currently, 475 species, or 36 percent, of the 1,311 listed species 
in the United States under the jurisdiction of the Service have 
designated critical habitat. We address the habitat needs of all 1,311 
listed species through conservation mechanisms such as listing, section 
7 consultations, the section 4 recovery planning process, the section 9 
protective prohibitions of unauthorized take, section 6 funding to the 
States, the section 10 incidental take permit process, and cooperative, 
non-regulatory efforts with private landowners. The Service believes 
that these measures may make the difference between extinction and 
survival for many species.
    In considering exclusions of areas proposed for designation, we 
evaluated the benefits of designation in light of Gifford Pinchot Task 
Force v. U.S. Fish and Wildlife Service, 378 F. 3d 1059 (9th Cir 2004) 
(hereinafter Gifford Pinchot). In that case, the Ninth Circuit 
invalidated the Service's regulation defining ``destruction or adverse 
modification of critical habitat.'' In response, on December 9, 2004, 
the Director issued guidance to be considered in making section 7 
adverse modification determinations. This proposed critical habitat 
designation does not use the invalidated regulation in our 
consideration of the benefits of including areas in this proposed 
designation. The Service will carefully manage future consultations 
that analyze impacts to designated critical habitat, particularly those 
that appear to be resulting in an adverse modification determination. 
Such consultations will be reviewed by the Regional Office prior to 
completion to ensure that an adequate analysis has been conducted that 
is informed by the Director's guidance.
    On the other hand, to the extent that designation of critical 
habitat provides protection, that protection can come at significant 
social and economic cost. The mere administrative process of 
designation of critical habitat is expensive, time-consuming, and 
controversial. The current statutory framework of critical habitat, 
combined with past judicial interpretations of the statute, make 
critical habitat the subject of excessive litigation. As a result, 
critical habitat designations are driven by litigation and courts 
rather than biology, and are made at a time and under a time frame that 
limits our ability to obtain and evaluate the scientific and other 
information required to make the designation most meaningful.
    In light of these circumstances, the Service believes that 
additional agency discretion would allow our focus to return to those 
actions that provide the greatest benefit to the species most in need 
of protection.

Procedural and Resource Difficulties in Designating Critical Habitat

    We have been inundated with lawsuits for our failure to designate 
critical habitat, and we face a growing number of lawsuits challenging 
critical habitat determinations once they are made. These lawsuits have 
subjected the Service to an increasing series of court orders and 
court-approved settlement agreements that now consume nearly the entire 
listing program budget. This leaves the Service with little ability to 
prioritize its activities to direct scarce listing resources to the 
listing program actions with the most biologically urgent species 
conservation needs.
    The consequence of the critical habitat litigation activity is that 
limited listing funds are used to defend active lawsuits, to respond to 
Notices of Intent (NOIs) to sue relative to critical habitat, and to 
comply with the growing number of adverse court orders. As a result, 
listing petition responses, the Service's own proposals to list 
critically imperiled species, and final listing determinations on 
existing proposals are all significantly delayed.
    The accelerated schedules of court-ordered designations have left 
the Service with limited ability to provide for public participation or 
to ensure a defect-free rulemaking process before making decisions on 
listing and critical habitat proposals, due to the risks associated 
with noncompliance with judicially imposed deadlines. This, in turn, 
fosters a second round of litigation in which those who fear adverse 
impacts from critical habitat designations challenge those 
designations. The cycle of litigation appears endless and is very 
expensive, thus diverting resources from conservation actions that may 
provide relatively more benefit to imperiled species.
    The costs resulting from the designation include legal costs, the 
cost of preparation and publication of the designation, the analysis of 
the economic effects and the cost of requesting and responding to 
public comment, and in some cases the costs of compliance with the 
National Environmental Policy Act (NEPA; 42 U.S.C. 4371 et seq.). These 
costs, which are not required for many other conservation actions, 
directly reduce the funds available for direct and tangible 
conservation actions.

Background

    It is our intent to discuss only those topics directly relevant to 
the designation of critical habitat in this proposed rule. For more 
information on these species, refer to the final rule listing the 
Peck's cave amphipod, Comal Springs dryopid beetle, and Comal Springs 
riffle beetle that published in the Federal Register on December 18, 
1997 (62 FR 66295).
    All three of the listed species proposed for critical habitat 
designation are freshwater invertebrates. The Peck's cave amphipod is 
an eyeless, subterranean (below ground) arthropod that has been found 
in Comal Springs and Hueco Springs (also spelled Waco Springs). Both 
spring systems are located in Comal County, Texas. The Comal Springs 
dryopid beetle is a subterranean insect with vestigial (poorly 
developed, non-functional) eyes. The species has been found in two 
spring systems (Comal Springs and Fern Bank Springs) that are located 
in Comal and Hays counties, respectively. The Comal Springs riffle 
beetle is an aquatic insect that is primarily restricted to surface 
water associated with Comal Springs in Comal County and with San Marcos 
Springs in Hays County.
    The four spring systems (Comal, Fern Bank, Hueco, and San Marcos) 
proposed as critical habitat units are produced by discharge of aquifer 
spring water along the Balcones fault zone at the edge of the Edwards 
Plateau in central Texas. The source of water flows for Comal Springs 
and San Marcos Springs is the San Antonio segment of the Edwards 
aquifer. This aquifer is characterized by highly varied, below ground 
spaces that have been hollowed out within limestone bedrock through 
dissolution by rainwater. Groundwater is held and conveyed within these 
hollowed-out spaces, which range in size from honeycomb-like pores to 
large caverns. The San Antonio segment of the aquifer occurs in a 
crescent-shaped section over a distance of 176 mi (miles) (283 
kilometers (km)) from the town of Brackettville in Kinney County on the 
segment's west side over to the town of Kyle in Hays County at the 
segment's northeast side. Groundwater generally moves from recharge 
areas in the southwest part of the San Antonio

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segment and travels toward discharge areas in the northeast part of the 
segment, which includes Comal Springs and San Marcos Springs. The area 
that recharges groundwater coming to Comal Springs may occur as much as 
62 mi (100 km) away from the springs (Brune 1981, p. 130). Hueco 
Springs is recharged locally from the local watershed basin and 
possibly by the San Antonio segment of the Edwards aquifer (Guyton and 
Associates 1979, p. 2). The source of water for Fern Bank Springs has 
not been determined. Fern Bank Springs discharges water from the upper 
member of the Glen Rose Formation, and its flow could originate 
primarily from that unit; however, water discharged from the springs 
could also be (1) drainage from the nearby Edwards aquifer recharge 
zone, (2) water lost from the Blanco River, or (3) a combination of all 
three sources (Veni 2006, p. 1).
    Comal Springs and San Marcos Springs are the two largest spring 
systems in Texas with respective mean annual flows of 284 and 170 cubic 
feet per second (8 and 5 cubic meters per second) (Fahlquist and 
Slattery 1997, p. 1; Slattery and Fahlquist 1997, p. 1). Both spring 
systems emerge as a series of spring outlets along the Balcones fault 
that follows the edge of the Edwards Plateau in Texas. Fern Bank 
Springs and Hueco Springs have considerably smaller flows and consist 
of one main spring with several satellite springs or seep areas.
    The four spring systems proposed for critical habitat are 
characterized by high water quality and relatively constant water flows 
with temperatures that range from 68 to 75 [deg]F (Fahrenheit) (20 to 
24 [deg]C (Celsius)). Due to the underlying limestone aquifer, 
discharged water from these springs has a carbonate chemistry (Ogden et 
al. 1986, p. 103). Although flows from San Marcos Springs can vary 
according to fluctuations in the source aquifer, records indicate that 
this spring system has never ceased flowing. San Marcos Springs has 
been monitored since 1894, and has exhibited the greatest flow 
dependability of any major spring system in central Texas (Puente 1976, 
p. 27). Comal Springs has a flow record nearly comparable to that of 
San Marcos Springs; however, Comal Springs ceased flowing from June 13 
to November 3, 1956, during a severe drought (U.S. Army Corps of 
Engineers 1965, p. 59). Water pumping from the aquifer contributed to 
cessation of flow at Comal Springs during the drought period (U.S. Army 
Corps of Engineers 1965, p. 59). Hueco Springs has gone dry a number of 
times in the past during drought periods (Puente 1976, p. 27; Guyton 
and Associates 1979, p. 46). Although flow records are unavailable for 
Fern Bank Springs, the spring system is considered to be perennial 
(Barr 1993, p. 39).
    Each of the four spring systems typically provides adequate 
resources to sustain life cycle functions for resident populations of 
the Peck's cave amphipod, Comal Springs dryopid beetle, or Comal 
Springs riffle beetle. However, a primary threat to the three 
invertebrate species is the potential failure of spring flow due to 
drought or excessive groundwater pumping, which could result in loss of 
aquatic habitat for the species. Although these invertebrate species 
persisted at Comal Springs in the 1950s despite drought conditions, all 
three species are aquatic and require water to complete their 
individual life cycles.
    Bowles et al. (2003, p. 379) pointed out that the mechanism by 
which the Comal Springs riffle beetle survived the drought and the 
extent to which its population was negatively impacted are uncertain. 
Bowles et al. (2003, p. 379) speculated that the riffle beetle may be 
able to retreat back into spring openings or burrow down to wet areas 
below the surface of the streambed.
    Barr (1993, p. 55) found Comal Springs dryopid beetles in spring 
flows with low volume discharge as well as high volume discharge and 
suggested that presence of the species did not necessarily depend on a 
high spring flow. However, Barr (1993, p. 61) noted that effects on 
both subterranean species (dryopid beetle and amphipod) from extended 
loss of spring flow and low aquifer levels could not be predicted due 
to limited knowledge about their life cycles.

Previous Federal Actions

    The final rule to list Peck's cave amphipod, Comal Springs dryopid 
beetle, and Comal Springs riffle beetle as endangered was published in 
the Federal Register on December 18, 1997 (62 FR 66295). Critical 
habitat was not designated at the time of listing due to the 
determination by the Service that designation for the three 
invertebrate species would not provide benefits to the species beyond 
listing and any evaluation of activities required under section 7 of 
the Act. There is no recovery plan for these species. The lack of 
designated critical habitat for these species was subsequently 
challenged by the Center for Biological Diversity in the U.S. District 
Court for the District of Columbia, and this proposed rule to designate 
critical habitat is part of a stipulated settlement agreement between 
the plaintiff and the Service (see Center for Biological Diversity v. 
Gale Norton, Secretary of the Interior Civil Action No. 03-2402 (JDB)).

Critical Habitat

    Critical habitat is defined in section 3 of the Act as--(i) the 
specific areas within the geographical area occupied by a species, at 
the time it is listed in accordance with the Act, on which are found 
those physical or biological features (I) essential to the conservation 
of the species and (II) that may require special management 
considerations or protection; and (ii) specific areas outside the 
geographical area occupied by a species at the time it is listed, upon 
a determination that such areas are essential for the conservation of 
the species. Conservation, as defined under section 3 of the Act, means 
to use and the use of all methods and procedures that are necessary to 
bring any endangered species or threatened species to the point where 
the measures provided under the Act are no longer necessary. Such 
methods and procedures include, but are not limited to, all activities 
associated with scientific resources management such as research, 
census, law enforcement, habitat acquisition and maintenance, 
propagation, live trapping, and transplantation, and, in the 
extraordinary case where population pressures within a given ecosystem 
cannot be otherwise relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the prohibition against destruction or adverse modification of 
critical habitat with regard to actions carried out, funded, or 
authorized by a Federal agency. Section 7 requires consultation on 
Federal actions that are likely to result in the destruction or adverse 
modification of critical habitat. The designation of critical habitat 
does not affect land ownership or establish a refuge, wilderness, 
reserve, preserve, or other conservation area. Such designation does 
not allow government or public access to private lands. Section 7 is a 
purely protective measure and does not require implementation of 
restoration, recovery, or enhancement measures.
    To be included in a critical habitat designation, the habitat 
within the area occupied by the species must first have features that 
are essential to the conservation of the species. Critical habitat 
designations identify, to the extent known using the best scientific 
data available, habitat areas that provide essential life cycle needs 
of the species (i.e., areas on which are found the

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primary constituent elements (PCEs), as defined at 50 CFR 424.12(b)).
    Habitat occupied at the time of listing may be included in critical 
habitat only if the essential features thereon may require special 
management or protection. Thus, we do not include areas where existing 
management is sufficient to conserve the species. (As discussed below, 
such areas may also be excluded from critical habitat under section 
4(b)(2) of the Act.) Accordingly, when the best available scientific 
data do not demonstrate that the conservation needs of the species 
require additional areas, we will not designate critical habitat in 
areas outside the geographical area occupied by the species at the time 
of listing. An area currently occupied by the species but not known to 
be occupied at the time of listing will likely, but not always, be 
essential to the conservation of the species and, therefore, will 
typically be included in the critical habitat designation.
    The Service's Policy on Information Standards Under the Endangered 
Species Act, published in the Federal Register on July 1, 1994 (59 FR 
34271), and Section 515 of the Treasury and General Government 
Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658) 
and the associated Information Quality Guidelines issued by the 
Service, provide criteria, establish procedures, and provide guidance 
to ensure that decisions made by the Service represent the best 
scientific data available. They require Service biologists, to the 
extent consistent with the Act and with the use of the best scientific 
data available, to use primary and original sources of information as 
the basis for recommendations to designate critical habitat. When 
determining which areas are critical habitat, a primary source of 
information is generally the listing package for the species. 
Additional information sources include the scientific information 
contained in the recovery plan for the species, articles in peer-
reviewed journals, conservation plans developed by States and counties, 
scientific status surveys and studies, biological assessments, or other 
unpublished materials and expert opinion or personal knowledge. All 
information is used in accordance with the provisions of Section 515 of 
the Treasury and General Government Appropriations Act for Fiscal Year 
2001 (Pub. L. 106-554; H.R. 5658) and the associated Information 
Quality Guidelines issued by the Service.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific data available. Habitat is often 
dynamic, and species may move from one area to another over time. 
Furthermore, we recognize that designation of critical habitat may not 
include all of the habitat areas that may eventually be determined to 
be necessary for the recovery of the species. For these reasons, 
critical habitat designations do not signal that habitat outside the 
designation is unimportant or may not be required for recovery.
    Areas that support populations, but are outside the critical 
habitat designation, will continue to be subject to conservation 
actions implemented under section 7(a)(1) of the Act and to the 
regulatory protections afforded by the section 7(a)(2) jeopardy 
standard, as determined on the basis of the best available information 
at the time of the action. Federally funded or permitted projects 
affecting listed species outside their designated critical habitat 
areas may still result in jeopardy findings in some cases. Critical 
habitat designations made on the basis of the best available 
information at the time of designation will not control the direction 
and substance of future recovery plans, habitat conservation plans, or 
other species conservation planning efforts if new information 
available to these planning efforts calls for a different outcome.

Methods

    As required by section 4(b)(2) of the Act, we use the best 
scientific data available in determining areas that contain the 
features that are essential to the conservation of the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle 
beetle. We do not propose to designate any areas outside the 
geographical areas presently occupied by these species.
    We reviewed available information that pertains to the presence and 
habitat requirements of these three invertebrate species such as 
research published in peer-reviewed articles, data in reports submitted 
during section 7 consultations, contracted surveys, agency reports and 
databases, and aerial photographs. Information that has been reviewed 
includes, but is not limited to, Holsinger (1967), Bosse et al. (1988), 
Barr and Spangler (1992), Arsuffi (1993), Barr (1993), Bio-West (2001, 
2002a, 2002b, 2003, 2004), Bowles et al. (2003), Fries et al. (2004), 
and Krejca (2005). As part of the process, we also reviewed the overall 
approach to conservation of these species undertaken by local, State, 
and Federal agencies, and private and non-governmental organizations 
operating within the species' range since their listing in 1997.

Primary Constituent Elements

    In accordance with section 3(5)(A)(i) of the Act and regulations at 
50 CFR 424.12, in determining which areas to propose as critical 
habitat, we considered the geographical areas occupied by these species 
at the time they were listed, on which are found those physical and 
biological features (known as primary constituent elements or PCEs) 
that are essential to the conservation of the species and that may 
require special management considerations or protection. These features 
include, but are not limited to, the following:
    (1) Space for individual and population growth, and for normal 
behavior;
    (2) Food, water, air, light, minerals, or other nutritional or 
physiological requirements;
    (3) Cover or shelter;
    (4) Sites for breeding, reproduction, and rearing (or development) 
of offspring; and
    (5) Habitats that are protected from disturbance or are 
representative of the historic geographical and ecological 
distributions of a species.

Primary Constituent Elements for the Peck's Cave Amphipod, Comal 
Springs Dryopid Beetle, and Comal Springs Riffle Beetle

    During our determination of PCEs to be proposed for critical 
habitat of these listed invertebrates, we have reviewed a number of 
studies relevant to habitat needs of the Peck's cave amphipod, Comal 
Springs dryopid beetle, and Comal Springs riffle beetle. The specific 
PCEs required for the three listed invertebrates are derived from the 
biological needs of the species as described in the ``Background'' 
section of this proposal and in the December 18, 1997, final rule 
listing these species (62 FR 66295). The proposed critical habitat 
constitutes our best assessment of areas that (1) are within the 
geographical range occupied by at least one of the three invertebrate 
species, (2) were occupied at the time of listing or have subsequently 
been discovered to be occupied, (3) are considered to contain features 
essential to the conservation of these species, and (4) that may 
require special management for conservation of these species. Based on 
our current knowledge of the life history, biology, and ecology of the 
species, and the habitat requirements for sustaining the essential life 
history functions of the species, we have determined that the Peck's 
cave amphipod, Comal Springs dryopid beetle, and Comal Springs riffle 
beetle require the PCEs described below.

[[Page 40592]]

The PCEs apply to all three species unless otherwise noted.
    PCE 1. High-quality water with pollutant levels of soaps, 
detergents, heavy metals, pesticides, fertilizer nutrients, petroleum 
hydrocarbons, and semi-volatile compounds such as industrial cleaning 
agents no greater than those documented to currently exist (Brown 1987, 
p. 261) and including:

    (a) Low salinity with total dissolved solids that generally 
range from about 307 to 368 milligrams per liter (mg/L); and
    (b) Low turbidity that generally is less than 5 nephelometric 
(measurement of turbidity in a water sample by passing light through 
the sample and measuring the amount of the light that is deflected) 
turbidity units (NTUs).

    These spring-adapted aquatic species live in high quality 
unpolluted groundwater and spring outflows that have low levels of 
salinity and turbidity. High-quality discharge water from springs and 
adjacent subterranean areas also help sustain habitat components, such 
as riparian vegetation that are essential to the Peck's cave amphipod, 
Comal Springs dryopid beetle, and Comal Springs riffle beetle. The two 
beetle species are thought to require water with adequate levels of 
dissolved oxygen for respiration (Brown 1987, p. 260; Arsuffi 1993, p. 
18). Amphipods generally require relatively high concentrations of 
oxygen and may serve as an indicator of good water quality (Arsuffi 
1993, p. 15). While definitive studies on the limits of tolerance and 
preference for these aquatic invertebrates have not been completed, 
they are exclusively found in aquatic habitats with constant 
temperature, low salinity, low turbidity, and extremely low levels of 
pollutants. In particular, respiration in the riffle beetle may be 
inhibited by pollutants such as soaps and detergents that can affect 
its respiratory mechanism (Brown 1987, p. 261). The dryopid beetle may 
also be affected by these particular pollutants since this species 
shares a similar respiratory structure (Arsuffi 1993, p. 18). However, 
biological tolerances for this species are not understood due to its 
existence within a subterranean habitat.
    Based on available literature, we propose that the PCE for high 
water quality in proposed critical habitat for these species should 
have an approximate range of salinity of about 307 to 368 mg/L and a 
turbidity of less than 5 NTUs. Fahlquist and Slattery (1997, p. 3) 
reported a low salinity (as measured by total dissolved solids) as low 
as 307 mg/L at Comal Springs, and Slattery and Fahlquist (1997, p. 4) 
found that San Marcos Springs had a low salinity of 328 mg/L. The two 
springs also have a low turbidity of less than 5 NTUs (Fahlquist and 
Slattery 1997, p. 3; Slattery and Fahlquist 1997, p. 4). Brune (1975, 
p. 94) reported a salinity for Hueco Springs of 322 mg/L. The highest 
salinity (as determined by analysis of total dissolved solids) that we 
have found associated with any of these invertebrates was 368 mg/L, 
which was reported from Fern Bank Springs on April 28, 2005 (Texas 
Water Development Board 2006, p. 1).
    PCE 2. Aquifer water temperatures that range approximately from 68 
to 75 [deg]F (20 to 24 [deg]C).
    The three listed invertebrate species complete their life cycle 
functions within a relatively narrow temperature range; water 
temperatures outside of this range could be harmful to these 
invertebrates. The temperature of spring water emerging from the 
Edwards aquifer at Comal Springs and San Marcos Springs ordinarily 
occurs within a narrow range of approximately 72 to 75 [deg]F (22 to 24 
[deg]C) (Fahlquist and Slattery 1997, pp. 3-4; Groeger et al. 1997, pp. 
282-283). Hueco Springs and Fern Bank Springs have temperature records 
of 68 to 71 [deg]F (20 to 22 [deg]C) (George 1952, p. 52; Brune 1975, 
p. 94; Texas Water Development Board 2006, p. 1).
    PCE 3. A hydrologic regime that provides adequate levels of 
dissolved oxygen in the approximate range of 4.0 to 10.0 mg/L for 
respiration of the Comal Springs riffle beetle and Comal Springs 
dryopid beetle.
    Respiration in most beetle species belonging to the family Elmidae 
(which includes the Comal Springs riffle beetle) typically requires 
flowing waters highly saturated with dissolved oxygen (Brown 1987, p. 
260). As a consequence, riffle beetles are most commonly associated 
with flowing water that has shallow riffles (small waves) or rapids 
(Brown 1987, p. 253). Riffle beetles are restricted to waters with high 
dissolved oxygen due to their reliance on a plastron (a thin sheet of 
air) that is held next to the underside of the body surface by a mass 
of minute, hydrophobic (tending to repel and not absorb water) hairs. 
The plastron functions as a gill by allowing oxygen to diffuse 
passively from water into the plastron and replace oxygen absorbed 
during respiration (Brown 1987, p. 260). Beetle species in the Elmidae 
family are generally limited to well-aerated water environments since 
gaseous exchange with a plastron can actually be reversed in oxygen-
depleted waters (Brown 1987, p. 260; Ward 1992, p. 130). The Comal 
Springs dryopid beetle also relies on a plastron for respiration, and 
this beetle species may also be affected by changes in oxygen levels 
caused by habitat modification (Arsuffi 1993, pp. 17-18).
    PCE 4. Food supply for the Peck's cave amphipod, Comal Springs 
dryopid beetle, and Comal Springs riffle beetle that includes, but is 
not limited to, detritus (decomposed materials), leaf litter, and 
decaying roots.
    Although specific food requirements of the three invertebrate 
species are unknown, the Peck's cave amphipod and dryopid beetle are 
most commonly found in areas where plant roots are inundated or 
otherwise influenced by aquifer water. Potential food sources for all 
three species in these areas include detritus (decomposed materials), 
leaf litter, and decaying roots; however, it is possible that these 
species feed on bacteria and fungi associated with decaying plant 
material. Both beetle species may be detritivores (detritus-feeding 
animals) that consume detrital materials in spring-influenced riparian 
zones (Gibson 2005, p. 1). The best information available indicates the 
Peck's cave amphipod is an omnivore (a species capable of consuming 
both animals and plants), which would enable the amphipod to exist as a 
scavenger or predator inside the aquifer in addition to using detritus 
in areas near spring outlets where plant roots interface with spring 
water (Gibson 2005, p. 1).
    Trees and shrubs in riparian areas adjacent to the spring system 
may provide plant growth necessary to maintain food sources such as 
decaying material for these invertebrates. Roots from trees and shrubs 
in proximity to spring outlets are most likely to penetrate underground 
down to the water pools where these roots can serve as habitat for the 
amphipod and dryopid beetle. We believe relatively intact riparian 
areas with trees and shrubs may provide an important function within 
areas proposed for critical habitat of the two subterranean species. 
According to patterns of plant canopies as determined from aerial 
photographs, trees and shrubs (and their root systems) are generally 
within 50 feet (ft) (15.2 meters (m)) of the edge of water in these 
spring systems.
    PCE 5. Bottom substrate in surface water habitat of the Comal 
Springs riffle beetle that is composed of sediment-free gravel and 
cobble ranging in size between 0.3 to 5.0 inches (in) (8-128 
millimeters (mm)).
    Although Comal Springs riffle beetles occur in conjunction with a 
variety of bottom substrates in surface water habitat, Bowles et al. 
(2003, p. 372) found that these beetles mainly occurred in areas with 
gravel and cobble

[[Page 40593]]

ranging between 0.3 to 5.0 in (8-128 mm) and did not occur in areas 
dominated by silt, sand, and small gravel. Collection efforts in areas 
of high sedimentation generally do not yield riffle beetles (Bowles et 
al. 2003, p. 376).
    The purpose of this proposed designation is the conservation of 
PCEs necessary to support the life history functions of these three 
species. Because not all life history functions require all of the 
PCEs, not all of the proposed critical habitat may contain all the 
PCEs. Each of the areas proposed in this rule have been determined to 
contain sufficient PCEs to provide for one or more of the life history 
functions of the Peck's cave amphipod, Comal Springs dryopid beetle, or 
Comal Spring riffle beetle. In some cases, the PCEs may exist as a 
result of ongoing Federal actions. As a result, ongoing Federal actions 
at the time of designation will be included in the baseline in any 
consultation conducted subsequent to designation.

Criteria for Defining Critical Habitat

    As required by section 4(b)(1)(A) of the Act, we use the best 
scientific data available in determining areas that contain the 
features that are essential to the conservation of the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle 
beetle, as discussed in the Methods section above. The proposed 
critical habitat areas described below constitute our best assessment 
of areas that (1) are within the geographical range occupied by at 
least one of the three invertebrate species, (2) were occupied at the 
time of listing or have subsequently been discovered to be occupied, 
(3) are considered to contain features essential to the conservation of 
these species (as explained above in the section on PCEs), and (4) that 
may require special management for conservation of these species. We 
are proposing critical habitat designation where these four items 
overlap. This does not imply that unoccupied areas outside of the 
proposed critical habitat areas do not need special management in order 
to maintain the habitat and PCEs within the designation. Due to the 
nature of this aquatic system, habitat of listed species can be 
affected by activities such as water withdrawals, construction, etc., 
that take place outside of occupied habitat. Such activities can affect 
the quantity and quality of water flowing into the occupied habitat of 
these listed invertebrates.
    Peck's cave amphipod--The Peck's cave amphipod has been found in 
Comal Springs and Hueco Springs, which are both located in Comal 
County. While limited data have been collected on the extent to which 
this subterranean species exists below ground away from outlets of 
spring systems, other species within the genus Stygobromus are known to 
be widely distributed in groundwaters and cave systems (Holsinger 1972, 
p. 65). Although this species could possibly range throughout the 4 mi 
(8 km) distance between the two habitat spring systems through the 
``honeycomb'' pores and conduits of the Edwards aquifer, it is not 
known whether below ground connections between Comal Springs and Hueco 
Springs exist in the aquifer. Hueco Springs itself is fed by surface 
water from the Guadalupe River basin and may only have a secondary 
connection to the Edwards aquifer (Guyton and Associates 1979, p. 2). 
The only specific location information we have for this species 
regarding its distribution in the aquifer, aside from the spring 
openings, is an observation of Peck's cave amphipods at the bottom of a 
well (Panther Canyon well) that is located approximately 360 ft (110 m) 
away from the head outlet of Spring Run No. 1 (as designated in Barr 
and Spangler 1992, Fig. 1 on p. 42) in the Comal Springs complex 
(Krejca 2005, p. 83). We propose to designate critical habitat for the 
species in aquatic habitat of both Comal Springs and Hueco Springs. To 
include amphipod food sources in root/water interfaces around spring 
outlets, we also propose an area consisting of a 50 ft (15.2 m) 
distance from spring outlets of both Comal Springs and Hueco Springs 
(including several satellite springs that are located between the main 
outlet of Hueco Springs and the Guadalupe River). We believe that this 
50 ft distance defines the lateral extent of critical habitat that 
contains PCEs necessary to provide for life functions of the Peck's 
cave amphipod with respect to roots that can penetrate into the 
aquifer. Based on the 50 ft (15.2 m) distance, the areas proposed for 
the amphipod critical habitat are about 38.1 ac (15.4 ha) at Comal 
Springs and 0.4 ac (0.2 ha) at Hueco Springs. The acreages were 
calculated with a computer-based Geographical Information System (GIS).
    Comal Springs dryopid beetle--The Comal Springs dryopid beetle has 
been found in only two spring systems (Comal Springs and Fern Bank 
Springs) located in Comal and Hays counties, respectively. The 
subterranean species is primarily collected near spring outlets (Barr 
and Spangler 1992, p. 41). While the extent to which the dryopid beetle 
inhabits subterranean areas away from spring outlets is unknown, this 
species does not swim and may be limited to relatively short ranges 
within the aquifer. In addition, immature stages of the species are 
thought to be terrestrial and require access to spring outlets (Barr 
1993, p. 56). Barr and Spangler (1992, p. 41) collected larvae of the 
dryopid beetle near spring outlets of Comal Springs and believed that 
the larvae were associated with ceilings of spring orifices. Extension 
of the dryopid beetle into the aquifer may also be limited by the lack 
of food materials associated with decaying plant roots that occur near 
spring orifices.
    For critical habitat of the Comal Springs dryopid beetle, we 
propose aquatic habitat and a 50 ft (15.2 m) distance from spring 
outlets of Comal Springs and Fern Bank Springs. The 50 ft distance 
(15.2 m) is based on evaluations of aerial photographs showing tree and 
shrub canopies occurring in proximity to spring outlets at both spring 
systems. These plant canopies reflect approximate distances where plant 
root systems interface with water flows of the two spring systems. 
Based on the 50 ft (15.2 m) distance, the area proposed for dryopid 
beetle critical habitat at Comal Springs is about 38.1 ac (15.4 ha) and 
1.4 ac (0.6 ha) at Fern Bank Springs. These acreages include areas 
believed to be occupied and that contain PCEs necessary to provide for 
life history functions of the Comal Springs dryopid beetle. The 
acreages were calculated with GIS.
    Comal Springs riffle beetle--For the Comal Springs riffle beetle, 
habitat is primarily restricted to surface water in two impounded 
spring systems that are located within Comal and Hays counties in 
central Texas. In Comal County, the aquatic beetle species is found in 
various spring outlets of Comal Springs that occur within Landa Lake 
over a linear distance of about 0.9 mi (1.4 km). The species has also 
been found in outlets of San Marcos Springs in the upstream portion of 
Spring Lake in Hays County. However, populations of Comal Springs 
riffle beetles may exist elsewhere in Spring Lake since spring systems 
within the lake are interconnected and sampling to date for the species 
within the lake has been limited. Therefore, we propose designating an 
area that encompasses all of the spring outlets that are found within 
the same relatively small lake (excluding a slough (slack water) 
portion that lacks spring outlets). Apart from the slough portion, the 
approximate linear distance of Spring Lake at its greatest length is 
0.2 mi (0.3 km). We propose about 19.8 ac (8.0 ha) of aquatic habitat 
in Landa Lake and

[[Page 40594]]

about 10.5 ac (4.3 ha) of aquatic habitat in Spring Lake to be 
designated for critical habitat. These areas contain PCEs necessary to 
provide for life-history functions of the Comal Springs riffle beetle. 
The acreages were estimated by calculating the cross-hatched polygon 
area in two map figures of these lakes using GIS.
    When determining proposed critical habitat boundaries, we attempted 
to avoid including developed areas such as buildings, paved areas, and 
other structures that lack PCEs for the Peck's cave amphipod, Comal 
Springs dryopid beetle, and Comal Springs riffle beetle. However, the 
scale of the maps prepared under the parameters for publication within 
the Code of Federal Regulations may not reflect the exclusion of such 
developed areas. Any such structures and the surface under them are 
excluded by text in the proposed rule and are not proposed for 
designation as critical habitat. Where lakes are proposed, critical 
habitat does not include the lake bottom beyond 50 feet from the spring 
outlet. Therefore, Federal actions limited to these areas would not 
trigger section 7 consultation, unless they affect the species or PCEs 
of the critical habitat.
    We are proposing to designate critical habitat in areas that we 
have determined were occupied at the time of listing, contain 
sufficient PCEs to support life-history functions essential for the 
conservation of the species, and require special management or 
protection. The proposed units of Comal Springs, Fern Bank Springs, 
Hueco Springs, and San Marcos Springs are proposed for designation 
based on all PCEs being present to support at least one life process 
for the Peck's cave amphipod, Comal Springs dryopid beetle, and/or 
Comal Springs riffle beetle.
    Section 10(a)(1)(B) of the Act authorizes us to issue permits for 
the take of listed species incidental to otherwise lawful activities. 
An incidental take permit application must be supported by a habitat 
conservation plan (HCP) that identifies conservation measures that the 
permittee agrees to implement for the species to minimize and mitigate 
the impacts of the requested incidental take. We often exclude non-
Federal public lands and private lands that are covered by an existing 
operative HCP and executed implementation agreement under section 
10(a)(1)(B) of the Act from designated critical habitat because the 
benefits of exclusion outweigh the benefits of inclusion as discussed 
in section 4(b)(2) of the Act. There are no non-Federal lands or 
private lands covered under an HCP within the areas considered for 
critical habitat; therefore, none have been excluded.

Special Management Considerations or Protections

    When designating critical habitat, we assess whether the areas 
determined to be occupied at the time of listing and containing the 
PCEs may require special management considerations or protections. As 
we undertake the process of designating critical habitat for a species, 
we first evaluate lands defined by those physical and biological 
features essential to the conservation of the species for inclusion in 
the designation under section 3(5)(A) of the Act. Secondly, we evaluate 
lands defined by those features to assess whether they may require 
special management considerations or protection.
    Primary threats to the spring systems proposed for designation as 
critical habitat for the three invertebrate species that may require 
special management are summarized in Table 2 below. The threats for 
individual springs vary according to the degree of urbanization and 
availability of aquifer source water, but possible threats generally 
include prolonged cessation of spring flows (in 1956, Comal Springs at 
New Braunfels did not flow from mid-June to November (U.S. Army Corps 
of Engineers 1965)) as a result of the loss of hydrological 
connectivity within the aquifer (e.g., groundwater pumping, excavation, 
concrete filling), pollutants (e.g., stormwater drainage, pesticide 
use), and non-native species (e.g., biological control, sport fish 
stocking). To address the threats affecting these three invertebrate 
species, certain special management actions may be required, for 
example, maintenance of sustainable groundwater use and subsurface 
flows, use of adequate buffers, selection of appropriate pesticides, 
and implementation of integrated pest management plans.

Proposed Critical Habitat Designation

    We are proposing four units as critical habitat for the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle 
beetle. The critical habitat areas described below constitute our best 
assessment at this time of areas occupied at the time of listing that 
contain the PCEs and may require special management or protection for 
conservation of these species. The four spring systems proposed to be 
designated as critical habitat are (1) the Comal Springs Unit, (2) the 
Fern Bank Springs Unit, (3) the Hueco Springs Unit, and (4) the San 
Marcos Springs Unit. Table 1 below provides approximate areas (ac/ha) 
of these spring units that have been determined to meet the definition 
of critical habitat for the three listed invertebrates.

   Table 1.--Spring System Units, Distances From Spring Outlets, and Acreages of Aquatic Habitat Proposed for
Critical Habitat of Peck's Cave Amphipod, Comal Springs Dryopid Beetle, and Comal Springs Riffle Beetle in Comal
                                            and Hays Counties, Texas
----------------------------------------------------------------------------------------------------------------
                                                                                                     Proposed
                                       Spring systems proposed                                       critical
               Species                   for critical habitat   Distance from spring outlets for      habitat
                                                areas           proposed critical habitat ft (m)    acreage ac
                                                                                                       (ha)
----------------------------------------------------------------------------------------------------------------
Peck's cave amphipod.................  Comal Springs Unit.....  50 (15.2).......................     38.1 (15.4)
                                       Hueco Springs Unit.....  50 (15.2).......................       0.4 (0.2)
Comal Springs dryopid beetle.........  Comal Springs Unit.....  50 (15.2).......................     38.1 (15.4)
                                       Fern Bank Springs Unit.  50 (15.2).......................       1.4 (0.6)
Comal Springs riffle beetle..........  Comal Springs Unit.....  Not applicable..................      19.8 (8.0)
                                       San Marcos Springs Unit  Not applicable..................      10.5 (4.3)
----------------------------------------------------------------------------------------------------------------

    Table 2 below summarizes land ownership and threats for the four 
spring systems proposed for critical habitat. Land ownership for these 
spring systems involves only the State of Texas, municipalities, and 
private landowners and does not involve Federal or Tribal holdings. 
Comal Springs and San Marcos Springs are surrounded, respectively, by 
the cities of New Braunfels and San Marcos. Both Comal Springs and San 
Marcos Springs

[[Page 40595]]

have been impounded with dams to form Landa Lake and Spring Lake, 
respectively. Possible threats to these urban spring systems include, 
but are not limited to, water withdrawals, pesticide use, and 
stormwater runoff of pollutants that have accumulated on impervious 
cover (paved driveways, parking lots, sidewalks, etc.) in urban areas. 
A thorough threats discussion is found in the December 18, 1997, final 
rule listing these species (62 FR 66295).

        Table 2.--Ownership and Threats to Springs or Listed Species for Proposed Critical Habitat Units
----------------------------------------------------------------------------------------------------------------
                                             Ownership of proposed
     Proposed critical habitat units       critical habitat by listed      Threats to spring system or listed
                                                species ac (ha)                         species
----------------------------------------------------------------------------------------------------------------
Comal Springs Unit, Comal County........  Peck's cave amphipod.......  Water withdrawals, hazardous materials
                                           State: 19.8 (8.0).........   spills, pesticide use, excavation/
                                           Municipal: 7.3 (3.0)......   construction, stormwater pollutants,
                                           Private: 11.0 (4.5).......   invasive species, and well entrainment.
                                          Comal Springs dryopid
                                           beetle.
                                           State: 19.8 (8.0).........
                                           Municipal: 7.3 (3.0)......
                                           Private: 11.0 (4.5).......
                                          Comal Springs riffle beetle
                                           State: 19.8 (8.0).........
Fern Bank Springs Unit, Hays County.....  Comal Springs dryopid        Water withdrawals, excavation/
                                           beetle.                      construction, and pesticide use.
                                           Private: 1.4 (0.6)........
Hueco Springs Unit, Comal County........  Peck's cave amphipod.......  Water withdrawals, hazardous materials
                                           Private: 0.4 (0.2)........   spills, pesticide use, excavation/
                                                                        construction, stormwater pollutants, and
                                                                        well entrainment
San Marcos Springs Unit, Hays County....  Comal Springs riffle beetle  Water withdrawals, hazardous materials
                                           State: 10.5 (4.3).........   spills, pesticide use, excavation/
                                                                        construction, stormwater pollutants, and
                                                                        invasive species.
----------------------------------------------------------------------------------------------------------------

    Fern Bank Springs and Hueco Springs occur in rural areas and are 
relatively unaffected by current urban activities in the vicinity of 
the springs. The satellite springs of Hueco Springs that lie between 
the main outlet and the Blanco River are located within a privately 
owned campground that has developed campsites occurring among these 
satellite springs. As compared to the other two spring systems, threats 
to Fern Bank Springs and Hueco Springs from surrounding land surface 
uses are currently minimal, as noted above in Table 2.
    We present brief descriptions of all units and reasons why they 
meet the definition of critical habitat for Peck's cave amphipod, Comal 
Springs dryopid beetle, and Comal Springs riffle beetle below. Maps of 
the proposed critical habitat units are provided in the Proposed 
Regulation Promulgation section of this proposed rule.

Comal Springs Unit--Comal County, Texas

    The Comal Springs system provides habitat for all three listed 
invertebrate species along with a federally listed fish, the endangered 
fountain darter (Etheostoma fonticola). No other critical habitat has 
been designated at this spring system. Comal Springs provides all of 
the PCEs necessary for conservation of the three invertebrate species. 
The spring system primarily occurs as a series of spring outlets that 
lie along the west shoreline of Landa Lake and within the lake itself. 
This nearly L-shaped lake is surrounded by the City of New Braunfels. 
Practically all of the spring outlets and spring runs associated with 
Comal Springs occur within the upper part of the lake above the 
confluence of Spring Run No. 1 with the lake. The land ownership of 
Comal Springs consists of private, municipal, and State holdings. The 
surface water and bottom of Landa Lake are State-owned. The City of New 
Braunfels owns approximately 40 percent of the land surface adjacent to 
the lake, and private landowners own approximately 60 percent. 
Approximate acreages of surface land ownership within the proposed 
critical habitat unit and threats to the unit are shown above in Table 
2.
    We propose to designate critical habitat for the three listed 
invertebrate species in the Comal Springs Unit as follows:
    (1) Landa Lake--(Comal Springs riffle beetle only)--aquatic habitat 
within the lake and outlying spring runs that occur from the confluence 
of Blieders Creek at the top of Landa Lake down to the lake's lowermost 
point of confluence with Spring Run No. 1. The part of Landa Lake that 
lies below the confluence with Spring Run No. 1 down to the impounding 
dams at the bottom of the lake is not included.
    (2) Aquatic habitat and shoreline areas of Landa Lake--(Peck's cave 
amphipod and Comal Springs dryopid beetle only)--aquatic habitat within 
the lake and outlying spring runs that occur from the confluence of 
Blieders Creek at the top of Landa Lake down to the lake's lowermost 
point of confluence with Spring Run No. 1. The part of Landa Lake that 
lies below the confluence with Spring Run No. 1 down to the impounding 
dams at the bottom of the lake is not included. Land areas along the 
shoreline of Landa Lake and on small islands inside the lake that are 
within a 50 ft (15.2 m) distance from habitat spring outlets are also 
included. The critical habitat proposed for the Peck's cave amphipod 
and Comal Springs dryopid beetle includes areas where PCEs exist for 
these two species and does not include areas where these features do 
not occur, such as buildings, lawns, or paved areas. Where lakes are 
proposed, critical habitat does not include the lake bottom where 
springs are absent.

Fern Bank Springs Unit--Hays County, Texas

    The Fern Bank Springs system provides habitat for only the Comal 
Springs dryopid beetle. No other critical habitat has been proposed for 
designation at this spring system. Fern Bank Springs provides all of 
the PCEs necessary for conservation of this species. The spring system 
is located approximately 0.2 mi (0.4 km) east of the junction of 
Sycamore Creek with the Blanco River in Hays County. The spring system 
consists of a main outlet and a number of seep springs that occur at 
the base of a high bluff overlooking the Blanco River. This spring 
system is located entirely on land that is privately

[[Page 40596]]

owned. Approximate acreages of land ownership encompassed within the 
proposed critical habitat unit and threats to the unit are shown above 
in Table 2.
    We propose to designate critical habitat for the Comal Springs 
dryopid beetle in the Fern Bank Springs Unit as follows:
    (1) Fern Bank Springs--aquatic habitat and land areas that are 
within a 50 ft (15.2 m) distance from spring outlets including the main 
outlet of Fern Bank Springs and its associated seep springs. The 
critical habitat proposed for the Comal Springs dryopid beetle includes 
only areas where PCEs exist for this species and does not include areas 
where these features do not occur, such as buildings, lawns, or paved 
areas. Where lakes are proposed, critical habitat does not include the 
lake bottom where springs are absent.

Hueco Springs Unit--Comal County, Texas

    The Hueco Springs system provides habitat for only the Peck's cave 
amphipod. No other critical habitat has been proposed for designation 
at this spring system. Hueco Springs provides all of the PCEs necessary 
for conservation of this species. The spring system has a main outlet 
that is located approximately 0.1 mi (0.2 km) south of the junction of 
Elm Creek with the Guadalupe River in Comal County. The main outlet 
itself lies approximately 500 ft (152 m) from the west bank of the 
Guadalupe River. Several satellite springs lie further south between 
the main outlet and the river. This spring system is located entirely 
on private land. The main outlet of Hueco Springs is located on 
undeveloped land, but the satellite springs occur within undeveloped 
areas of a privately owned campground. Approximate acreages of land 
ownership encompassed within the proposed critical habitat unit and 
threats to the unit are indicated above in Table 2.
    We propose to designate critical habitat for the Peck's cave 
amphipod within the Hueco Springs Unit as follows:
    (1) Hueco Springs--aquatic habitat and land areas that are within 
50 ft (15.2 m) from habitat spring outlets including the main outlet of 
Hueco Springs and its associated satellite springs. The critical 
habitat proposed for the Peck's cave amphipod includes only aquatic 
habitat areas where PCEs exist for this species.

San Marcos Springs Unit--Hays County, Texas

    The San Marcos Springs system provides habitat for the only Comal 
Springs riffle beetle. However, the San Marcos Springs system provides 
habitat for five other federally listed species: (1) The endangered 
fountain darter, (2) the endangered San Marcos gambusia (Gambusia 
georgei), (3) the threatened San Marcos salamander (Eurycea nana), (4) 
the endangered Texas blind salamander (Eurycea (formerly Typhlomolge) 
rathbuni), and (5) the endangered Texas wild-rice (Zizania texana). 
However, the San Marcos gambusia has not been found in surveys during 
recent years and is presumed to be extinct (Edwards 1999, p. 3). 
Critical habitat has been designated for the fountain darter, San 
Marcos gambusia, San Marcos salamander, and Texas wild-rice within 
Spring Lake and portions of the San Marcos River that lie downstream 
from Spring Lake. The San Marcos Springs unit provides all of the PCEs 
necessary for conservation of the Comal Springs riffle beetle. The 
spring system primarily occurs as a series of spring outlets that lie 
at the bottom of Spring Lake and along its shoreline. The lake is 
surrounded by the City of San Marcos in Hays County. The spring outlets 
associated with San Marcos Springs occur within the main part of the 
lake excluding the slough portion that exists as an arm of the lake. 
The land ownership involving San Marcos Springs consists entirely of 
State holdings. The surface water and bottom of Spring Lake are State-
owned; the State-affiliated Texas State University owns the adjacent 
land surface. Approximate acreages of surface land ownership in the 
proposed critical habitat unit and threats to the unit are shown above 
in Table 2.
    We propose to designate critical habitat for the Comal Springs 
riffle beetle in the San Marcos Springs unit as: Spring Lake--aquatic 
habitat areas within the lake upstream of Spring Lake dam with the 
exception of the slough portion of the lake upstream of its confluence 
with the main body.

Effects of Critical Habitat Designation

Section 7 Consultation

    Section 7 of the Act requires Federal agencies, including the 
Service, to ensure that actions they fund, authorize, or carry out are 
not likely to destroy or adversely modify critical habitat. In our 
regulations at 50 CFR 402.02, we define destruction or adverse 
modification as ``a direct or indirect alteration that appreciably 
diminishes the value of critical habitat for both the survival and 
recovery of a listed species. Such alterations include, but are not 
limited to, alterations adversely modifying any of those physical or 
biological features that were the basis for determining the habitat to 
be critical.'' However, recent decisions by the 5th and 9th Circuit 
Courts of Appeal have invalidated this definition (see Gifford Pinchot 
and Sierra Club v. U.S. Fish and Wildlife Service et al., 245 F.3d 434, 
442F (5th Cir 2001)). Pursuant to current national policy and the 
statutory provisions of the Act, destruction or adverse modification is 
determined on the basis of whether, with implementation of the proposed 
Federal action, the affected critical habitat would remain functional 
(or retain the current ability for the PCEs to be functionally 
established) to serve the intended conservation role for the species.
    Section 7(a) of the Act requires Federal agencies, including the 
Service, to evaluate their actions with respect to any species that is 
proposed or listed as endangered or threatened and with respect to its 
critical habitat, if any is proposed or designated. Regulations 
implementing this interagency cooperation provision of the Act are 
codified at 50 CFR part 402.
    Section 7(a)(4) of the Act requires Federal agencies to confer with 
us on any action that is likely to jeopardize the continued existence 
of a proposed species or result in destruction or adverse modification 
of proposed critical habitat. This is a procedural requirement only. 
However, once proposed species becomes listed, or proposed critical 
habitat is designated as final, the full prohibitions of section 
7(a)(2) apply to any Federal action. The primary utility of the 
conference procedures is to maximize the opportunity for a Federal 
agency to adequately consider proposed species and critical habitat and 
avoid potential delays in implementing their proposed action as a 
result of the section 7(a)(2) compliance process, should those species 
be listed or the critical habitat designated.
    Under conference procedures, the Service may provide advisory 
conservation recommendations to assist the agency in eliminating 
conflicts that may be caused by the proposed action. The Service may 
conduct either informal or formal conferences. Informal conferences are 
typically used if the proposed action is not likely to have any adverse 
effects to the proposed species or proposed critical habitat. Formal 
conferences are typically used when the Federal agency or the Service 
believes the proposed action is likely to cause adverse effects to 
proposed species or critical habitat, inclusive of those that may cause 
jeopardy or adverse modification.

[[Page 40597]]

    The results of an informal conference are typically transmitted in 
a conference report; the results of a formal conference are typically 
transmitted in a conference opinion. Conference opinions on proposed 
critical habitat are typically prepared according to 50 CFR 402.14, as 
if the proposed critical habitat were designated. We may adopt the 
conference opinion as the biological opinion when the critical habitat 
is designated, if no substantial new information or changes in the 
action alter the content of the opinion (see 50 CFR 402.10(d)). As 
noted above, any conservation recommendations in a conference report or 
opinion are strictly advisory.
    If a species is listed or critical habitat is designated, section 
7(a)(2) of the Act requires Federal agencies to ensure that activities 
they authorize, fund, or carry out are not likely to jeopardize the 
continued existence of such a species or to destroy or adversely modify 
its critical habitat. If a Federal action may affect a listed species 
or its critical habitat, the responsible Federal agency (action agency) 
must enter into consultation with us. As a result of this consultation, 
compliance with the requirements of section 7(a)(2) will be documented 
through the Service's issuance of (1) a concurrence letter for Federal 
actions that may affect, but are not likely to adversely affect, listed 
species or critical habitat; or (2) a biological opinion for Federal 
actions that may affect, but are likely to adversely affect, listed 
species or critical habitat.
    When we issue a biological opinion concluding that a project is 
likely to result in jeopardy to a listed species or the destruction or 
adverse modification of critical habitat, we also provide reasonable 
and prudent alternatives to the project, if any are identifiable. 
``Reasonable and prudent alternatives'' are defined at 50 CFR 402.02 as 
alternative actions identified during consultation that can be 
implemented in a manner consistent with the intended purpose of the 
action, that are consistent with the scope of the Federal agency's 
legal authority and jurisdiction, that are economically and 
technologically feasible, and that the Director believes would avoid 
jeopardy to the listed species or destruction or adverse modification 
of critical habitat. Reasonable and prudent alternatives can vary from 
slight project modifications to extensive redesign or relocation of the 
project. Costs associated with implementing a reasonable and prudent 
alternative are similarly variable.
    Regulations at 50 CFR 402.16 require Federal agencies to reinitiate 
consultation on previously reviewed actions in instances where a new 
species is listed or critical habitat is subsequently designated that 
may be affected and the Federal agency has retained discretionary 
involvement or control over the action or such discretionary 
involvement or control is authorized by law. Consequently, some Federal 
agencies may request reinitiation of consultation with us on actions 
for which formal consultation has been completed, if those actions may 
affect subsequently listed species or designated critical habitat or 
adversely modify or destroy proposed critical habitat.
    Federal activities that may affect the Peck's cave amphipod, Comal 
Springs dryopid beetle, or Comal Springs riffle beetle or their 
designated critical habitat will require section 7 consultation under 
the Act. Activities on State, tribal, local, or private lands requiring 
a Federal permit (such as a permit from the U.S. Army Corps of 
Engineers under section 404 of the Clean Water Act or a permit under 
section 10(a)(1)(B) of the Act from the Service) or involving some 
other Federal action (funding from the Federal Highway Administration, 
Federal Aviation Administration, or Federal Emergency Management 
Agency) will also be subject to the section 7 consultation process. 
Federal actions requiring section 7 consultation also include pumping 
of Edwards aquifer water by Federal agencies, such as the Department of 
Defense or Service. Federal actions not affecting listed species or 
critical habitat, and actions on State, tribal, local, or private lands 
that are not federally funded, authorized, or permitted, do not require 
section 7 consultations.

Application of the Jeopardy and Adverse Modification Standards for 
Actions Involving Effects to the Peck's Cave Amphipod, Comal Springs 
Dryopid Beetle, and Comal Springs Riffle Beetle and Their Critical 
Habitat

Jeopardy Standard
    Prior to designation of critical habitat, the Service has applied 
an analytical framework for jeopardy analyses of Peck's cave amphipod, 
Comal Springs dryopid beetle, and Comal Springs riffle beetle that 
relies heavily on the importance of core area populations to the 
survival and recovery of these species. The section 7(a)(2) analysis is 
focused not only on these populations but also on the habitat 
conditions necessary to support them.
    The jeopardy analysis usually expresses the survival and recovery 
needs of the Peck's cave amphipod, Comal Springs dryopid beetle, and 
Comal Springs riffle beetle in a qualitative fashion without making 
distinctions between what is necessary for survival and what is 
necessary for recovery. Generally, if a proposed Federal action is 
incompatible with the viability of the affected core area 
population(s), inclusive of associated habitat conditions, a jeopardy 
finding is considered to be warranted, because of the relationship of 
each core area population to the survival and recovery of the species 
as a whole.

Adverse Modification Standard

    The analytical framework described in the Director's December 9, 
2004, memorandum would be used to complete section 7(a)(2) analyses for 
Federal actions affecting critical habitat for the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle 
beetle. The key factor related to the adverse modification 
determination is whether, with implementation of the proposed Federal 
action, the affected critical habitat would remain functional (or 
retain the current ability for the PCEs to be functionally established) 
to serve the intended conservation role for the species. Generally, the 
conservation role of critical habitat units for the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
is to have each unit support viable populations.
    Section 4(b)(8) of the Act requires us to briefly evaluate and 
describe in any proposed or final regulation that designates critical 
habitat those activities involving a Federal action that may destroy or 
adversely modify such habitat, or that may be affected by such 
designation. Activities that may destroy or adversely modify critical 
habitat may also jeopardize the continued existence of the species.
    Activities that may destroy or adversely modify critical habitat 
are those that alter the PCEs to an extent that the conservation value 
of critical habitat for Peck's cave amphipod, Comal Springs dryopid 
beetle, and Comal Springs riffle beetle is appreciably reduced. 
Activities that, when carried out, funded, or authorized by a Federal 
agency, may affect critical habitat and therefore result in 
consultation for these listed species include, but are not limited to:
    (1) Actions that can negatively affect the PCEs of the Peck's cave 
amphipod, Comal Springs dryopid beetle, or Comal Springs riffle beetle;
    (2) Activities that would significantly and detrimentally alter the 
water quality in any of the spring systems listed above

[[Page 40598]]

and would thereby destroy or adversely modify the critical habitat for 
any of theses species. These activities include, but are not limited 
to, sedimentation from construction or release of chemical or 
biological pollutants into the surface water or connected groundwater 
at a point source or by dispersed release (non-point source); such 
activities could also alter water conditions to a point that negatively 
affects these invertebrate species;
    (3) Actions that change the existing and historic flow regimes and 
would thereby significantly and detrimentally alter the PCEs necessary 
for conservation of these species. Such activities could include, but 
are not limited to, water withdrawal, impoundment, and water 
diversions. These activities could eliminate or reduce the habitat 
necessary for the growth, reproduction, or survival of these 
invertebrate species; and
    (4) Actions that remove hydraulic connectivity of the aquifer and 
the spring areas where it exists and would thereby negatively affect 
the PCEs of the proposed critical habitat of these species and the 
population dynamics of the species. Alteration of subsurface water 
flows through destruction of geologic features (for example, 
excavation) or creation of impediments to flow (for example, concrete 
filling), especially in proximity to spring outlets, could negatively 
alter the hydraulic connectivity necessary to sustain these species. It 
is necessary for subsurface habitat to remain intact with sufficient 
hydraulic connectivity of flow paths and conduits to ensure that PCEs 
(water quality, water quantity, and food supply) for the proposed 
critical habitat remain adequate for all three listed invertebrates.
    Due in large part to the nature of the aquifer and spring systems, 
ongoing human activities that occur outside the proposed critical 
habitat are unlikely to threaten the physical and biological features 
of the proposed critical habitat. However, future activities outside of 
the critical habitat may affect PCEs. Federal activities outside of 
critical habitat (such as groundwater pumping, pollution, etc.) are 
subject to review under section 7 of the Act if they may affect these 
species or adversely affect their critical habitat.
    We consider all of the units proposed as critical habitat to 
contain features essential to the conservation of the Peck's cave 
amphipod, Comal Springs dryopid beetle, or Comal Springs riffle beetle. 
All units are within the geographic range of the species, all were 
occupied by the species at the time of listing (based on observations 
made within the last 9 years), and are likely to be used by these 
listed invertebrates. Federal agencies already consult with us on 
activities in areas currently occupied by these listed invertebrates, 
or if the species may be affected by the action, to ensure that their 
actions do not jeopardize the continued existence of the Peck's cave 
amphipod, Comal Springs dryopid beetle, or Comal Springs riffle beetle.

Exclusions Under Section 4(b)(2) of the Act

    Section 4(b)(2) of the Act states that critical habitat shall be 
designated, and revised, on the basis of the best available scientific 
data after taking into consideration the economic impact, national 
security impact, and any other relevant impact of specifying any 
particular area as critical habitat. The Secretary of the Interior may 
exclude an area from critical habitat if (s)he determines that the 
benefits of exclusion outweigh the benefits of specifying such area as 
part of the critical habitat, unless (s)he determines, based on the 
best scientific data available, that the failure to designate such area 
as critical habitat will result in the extinction of the species. In 
making that determination, the Secretary is afforded broad discretion 
and the Congressional record is clear that in making a determination 
under this section, the Secretary has discretion as to which factors 
and how much weight will be given to any factor.
    The Service is conducting an economic analysis of the impacts of 
the proposed critical habitat designation and related factors, which 
will be available for public review and comment. Based on public 
comment on that document, the proposed designation itself, and the 
information in the final economic analysis, one or more areas may be 
excluded from critical habitat by the Secretary under the provisions of 
section 4(b)(2) of the Act. This is provided for in the Act, and in our 
implementing regulations at 50 CFR 424.19.
    Pursuant to section 4(b)(2) of the Act, we must consider relevant 
impacts in addition to economic ones. The lands within the proposed 
designation of critical habitat for Peck's cave amphipod, Comal Springs 
dryopid beetle, and Comal Springs riffle beetle are not owned or 
managed by the Department of Defense; there are currently no HCPs for 
these listed species; and the proposed designation does not include any 
Tribal lands or trust resources. We anticipate no impact to national 
security, Tribal lands, partnerships, or HCPs from this proposed 
critical habitat designation. A number of programs exist at the State 
and local levels (e.g., Edwards Aquifer Authority and Texas Commission 
for Environmental Quality) to protect the Edwards aquifer and manage 
spring flows.
    As a result of a ruling in a 1991 Court case (Sierra Club v. 
Secretary of the Interior, No. MO-91-CA-069), the Service identified 
minimum spring flows from Comal and San Marcos Springs likely to cause 
take and jeopardy for other listed aquatic species. The Edwards Aquifer 
Authority and other Edwards Aquifer water users are positively 
influencing water quantity and temperature that relate to PCEs. As a 
result of the Sierra Club lawsuit, the State legislature created the 
Edwards Aquifer Authority (EAA) through Senate Bill 1477 to regulate 
groundwater withdrawals. The EAA has issued withdrawal permits and 
created drought response plans that help protect the PCEs related to 
water quantity and temperature. The EAA has prepared a draft Habitat 
Conservation Plan to provide for water quantity in the aquifer and 
protect spring dependent species. When finalized, the plan is expected 
to help protect the aquifer. Other programs that provide some aquifer 
protection are Edwards Aquifer Rules and Phase I optional water quality 
measures of the Texas Commission on Environmental Quality (TCEQ). The 
Edwards Aquifer Rules provide protection for drinking water, and the 
Phase I measures provide protection for fountain darter, Texas wild-
rice, San Marcos salamander, and San Marcos gambusia. The Edwards 
Aquifer Rules protect water quality by reducing pollutant loading 
through the implementation of best management practices that can help 
prevent degradation of groundwater. The Phase I optional water quality 
measures include enhanced best management practices that protect 
sensitive karst features. These measures also contain other protective 
actions that can be applied to many types of new projects. The Edward 
Aquifer Rules and Phase I optional measures provide protections for the 
three Comal Springs invertebrates. In addition, the Phase I optional 
measures are not mandated for every project.
    Based on the best available information, we believe that all of 
these units contain the features essential to the species. As such, we 
have considered excluding, but have not proposed to exclude any lands 
from this proposed designation based on the potential impacts from 
these factors.

[[Page 40599]]

Economic Analysis

    An analysis of the economic impacts of proposing critical habitat 
for the Peck's cave amphipod, Comal Springs dryopid beetle, and Comal 
Springs riffle beetle is being prepared. We will announce the 
availability of the draft economic analysis as soon as it is completed, 
at which time we will seek public review and comment. At that time, 
copies of the draft economic analysis will be available by contacting 
the Austin Ecological Services Office (see ADDRESSES section).

Peer Review

    In accordance with our joint policy published in the Federal 
Register on July 1, 1994 (59 FR 34270), we will seek the expert 
opinions of at least three appropriate and independent specialists 
regarding this proposed rule (see DATES section). The purpose of such 
review is to ensure that our critical habitat designation is based on 
scientifically sound data, assumptions, and analyses. We will send 
copies of this proposed rule to these peer reviewers immediately 
following publication in the Federal Register. We will invite these 
peer reviewers to comment, during the public comment period, on the 
specific assumptions and conclusions regarding the proposed designation 
of critical habitat.
    We will consider all comments and information received during the 
comment period on this proposed rule during preparation of a final 
rulemaking. Accordingly, the final decision may differ from this 
proposal.

Public Hearings

    The Act provides for one or more public hearings on this proposal, 
if requested. Requests for public hearings must be made in writing at 
least 15 days prior to the close of the public comment period. We will 
schedule public hearings on this proposal, if any are requested, and 
announce the dates, times, and places of those hearings in the Federal 
Register and local newspapers at least 15 days prior to the first 
hearing.

Clarity of the Rule

    Executive Order 12866 requires each agency to write regulations and 
notices that are easy to understand. We invite your comments on how to 
make this proposed rule easier to understand, including answers to 
questions such as the following: (1) Are the requirements in the 
proposed rule clearly stated? (2) Does the proposed rule contain 
technical jargon that interferes with the clarity? (3) Does the format 
of the proposed rule (grouping and order of the sections, use of 
headings, paragraphing, and so forth) aid or reduce its clarity? (4) Is 
the description of the notice in the SUPPLEMENTARY INFORMATION section 
of the preamble helpful in understanding the proposed rule? (5) What 
else could we do to make this proposed rule easier to understand?
    Send a copy of any comments on how we could make this proposed rule 
easier to understand to: Office of Regulatory Affairs, Department of 
the Interior, Room 7229, 1849 C Street, NW., Washington, DC 20240. You 
may e-mail your comments to this address: [email protected].

Required Determinations

Regulatory Planning and Review

    In accordance with Executive Order 12866, this document is a 
significant rule in that it may raise novel legal and policy issues, 
but it is not anticipated to have an annual effect on the economy of 
$100 million or more or affect the economy in a material way. Due to 
the tight timeline for publication in the Federal Register, the Office 
of Management and Budget (OMB) has not formally reviewed this rule. We 
are preparing a draft economic analysis of this proposed action, which 
will be available for public comment, to determine the economic 
consequences of designating critical habitat. This economic analysis 
also will be used to determine compliance with Executive Order 12866, 
Regulatory Flexibility Act, Small Business Regulatory Enforcement 
Fairness Act, and Executive Order 12630.
    The types of Federal actions or authorized activities that may 
destroy or adversely modify proposed critical habitat, or that may be 
affected by such designation are listed above in the ``Effects of 
Critical Habitat Designation'' section. The availability of the draft 
economic analysis will be announced in the Federal Register and in 
local newspapers so that it is available for public review and comment. 
The draft economic analysis can be obtained by contacting the Austin 
Ecological Services Office (see ADDRESSES section).

Regulatory Flexibility Act (5 U.S.C. 601 et seq.)

    Under the Regulatory Flexibility Act (5 U.S.C. 601 et seq., as 
amended by the Small Business Regulatory Enforcement Fairness Act 
(SBREFA) of 1996), whenever an agency is required to publish a notice 
of rulemaking for any proposed or final rule, it must prepare and make 
available for public comment a regulatory flexibility analysis that 
describes the effects of the rule on small entities (i.e., small 
businesses, small organizations, and small government jurisdictions). 
However, no regulatory flexibility analysis is required if the head of 
the agency certifies the rule will not have a significant economic 
impact on a substantial number of small entities. The SBREFA amended 
the Regulatory Flexibility Act (RFA) to require Federal agencies to 
provide a statement of the factual basis for certifying that the rule 
will not have a significant economic impact on a substantial number of 
small entities.
    At this time, the Service lacks the available economic information 
necessary to provide an adequate factual basis for the required RFA 
finding. Therefore, the RFA finding is deferred until completion of the 
draft economic analysis prepared pursuant to section 4(b)(2) of the Act 
and E.O. 12866. This draft economic analysis will provide the required 
factual basis for the RFA finding. Upon completion of the draft 
economic analysis, the Service will publish a notice of availability of 
the draft economic analysis of the proposed designation and reopen the 
public comment period on the proposed designation for an additional 60 
days. The Service will include with the notice of availability, as 
appropriate, an initial regulatory flexibility analysis or a 
certification that the rule will not have a significant economic impact 
on a substantial number of small entities accompanied by the factual 
basis for that determination. The Service has concluded that deferring 
the RFA finding until completion of the draft economic analysis is 
necessary to meet the purposes and requirements of the RFA. Deferring 
the RFA finding in this manner will ensure that the Service makes a 
sufficiently informed determination based on adequate economic 
information and provides the necessary opportunity for public comment.

Executive Order 13211

    On May 18, 2001, the President issued an Executive Order (E.O. 
13211) on regulations that significantly affect energy supply, 
distribution, and use. Executive Order 13211 requires agencies to 
prepare Statements of Energy Effects when undertaking certain actions. 
This proposed rule to designate critical habitat for the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
is a significant rule under Executive Order 12866 in that it may raise 
novel legal or policy issues, but it is not expected to significantly 
affect energy supplies, distribution, or use since there are no 
pipelines, distribution facilities, power

[[Page 40600]]

grid stations, etc., within the boundaries of proposed critical 
habitat. Therefore, this action is not a significant energy action, and 
no Statement of Energy Effects is required. We will, however, further 
evaluate this issue as we conduct our economic analysis and review and 
revise this assessment as warranted.

Unfunded Mandates Reform Act (2 U.S.C. 1501 et seq.)

    In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 
1501), the Service makes the following findings:
    (a) This rule will not produce a Federal mandate. In general, a 
Federal mandate is a provision in legislation, statute, or regulation 
that would impose an enforceable duty upon State, local, tribal 
governments, or the private sector and includes both ``Federal 
intergovernmental mandates'' and ``Federal private sector mandates.'' 
These terms are defined in 2 U.S.C. 658(5)-(7). ``Federal 
intergovernmental mandate'' includes a regulation that ``would impose 
an enforceable duty upon State, local, or tribal governments'' with two 
exceptions. It excludes ``a condition of Federal assistance.'' It also 
excludes ``a duty arising from participation in a voluntary Federal 
program,'' unless the regulation ``relates to a then-existing Federal 
program under which $500,000,000 or more is provided annually to State, 
local, and tribal governments under entitlement authority,'' if the 
provision would ``increase the stringency of conditions of assistance'' 
or ``place caps upon, or otherwise decrease, the Federal Government's 
responsibility to provide funding,'' and the State, local, or tribal 
governments ``lack authority'' to adjust accordingly. At the time of 
enactment, these entitlement programs were: Medicaid; AFDC work 
programs; Child Nutrition; Food Stamps; Social Services Block Grants; 
Vocational Rehabilitation State Grants; Foster Care, Adoption 
Assistance, and Independent Living; Family Support Welfare Services; 
and Child Support Enforcement. ``Federal private sector mandate'' 
includes a regulation that ``would impose an enforceable duty upon the 
private sector, except (i) a condition of Federal assistance or (ii) a 
duty arising from participation in a voluntary Federal program.''
    The designation of critical habitat does not impose a legally 
binding duty on non-Federal government entities or private parties. 
Under the Act, the only regulatory effect is that Federal agencies must 
ensure that their actions do not destroy or adversely modify critical 
habitat under section 7. While non-Federal entities that receive 
Federal funding, assistance, or permits, or that otherwise require 
approval or authorization from a Federal agency for an action, may be 
indirectly impacted by the designation of critical habitat, the legally 
binding duty to avoid destruction or adverse modification of critical 
habitat rests squarely on the Federal agency. Furthermore, to the 
extent that non-Federal entities are indirectly impacted because they 
receive Federal assistance or participate in a voluntary Federal aid 
program, the Unfunded Mandates Reform Act would not apply; nor would 
critical habitat shift the costs of the large entitlement programs 
listed above on to State governments.
    (b) Due to current public knowledge of these three species' 
protection, the prohibition against take of these three species both 
within and outside of the proposed critical habitat areas, and the fact 
that critical habitat provides no incremental restrictions, we do not 
anticipate that this rule will significantly or uniquely affect small 
governments. As such, a Small Government Agency Plan is not required. 
We will, however, further evaluate this issue as we conduct our 
economic analysis and revise this assessment if appropriate.

Takings

    In accordance with Executive Order 12630 (``Government Actions and 
Interference with Constitutionally Protected Private Property 
Rights''), this rule is not anticipated to have significant takings 
implications. A takings implication assessment is not required. As 
discussed above, the designation of critical habitat affects only 
Federal actions. Although private parties that receive Federal funding, 
assistance, or require approval or authorization from a Federal agency 
for an action may be indirectly impacted by the designation of critical 
habitat, the legally binding duty to avoid destruction or adverse 
modification of critical habitat rests squarely on the Federal agency. 
Due to current public knowledge of these three species protections and 
the prohibition against take of these three species both within and 
outside of the proposed areas, we do not anticipate that property 
values will be affected by the critical habitat designation. However, 
we have not yet completed the economic analysis for this proposed rule. 
Once the economic analysis is available, we will review and revise this 
preliminary assessment as warranted.

Federalism

    In accordance with Executive Order 13132, the rule does not have 
significant Federalism effects. A Federalism assessment is not 
required. In keeping with Department of the Interior and Department of 
Commerce policy, we requested information from, and coordinated 
development of, this proposed critical habitat designation with 
appropriate State resource agencies in Texas. The proposed designation 
of critical habitat in areas currently occupied by the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
imposes no additional restrictions to those currently in place and, 
therefore, has little incremental impact on State and local governments 
and their activities. The proposed designation may have some benefit to 
these governments in that the areas that contain the features essential 
to the conservation of the species are more clearly defined, and the 
PCEs necessary to the conservation of these three species are 
specifically identified. While making this definition and 
identification does not alter where and what federally sponsored 
activities may occur, it may assist these local governments in long-
range planning (rather than waiting for case-by-case section 7 
consultations to occur).

Civil Justice Reform

    In accordance with Executive Order 12988, the Office of the 
Solicitor has determined that the rule does not unduly burden the 
judicial system and meets the requirements of sections 3(a) and 3(b)(2) 
of the Order. We propose designating critical habitat in accordance 
with the provisions of the Act. This proposed rule uses standard 
property descriptions and identifies the PCEs within the proposed 
designated areas to assist the public in understanding the habitat 
needs of the Peck's cave amphipod, Comal Springs dryopid beetle, and 
Comal Springs riffle beetle.

Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.)

    This rule does not contain any new collections of information that 
require approval by OMB under the Paperwork Reduction Act. This rule 
will not impose recordkeeping or reporting requirements on State or 
local governments, individuals, businesses, or organizations. An agency 
may not conduct or sponsor, and a person is not required to respond to, 
a collection of information unless it displays a currently valid OMB 
control number.

[[Page 40601]]

National Environmental Policy Act

    It is our position that, outside the Tenth Circuit, we do not need 
to prepare environmental analyses as defined by the NEPA in connection 
with designating critical habitat under the Endangered Species Act of 
1973, as amended. We published a notice outlining our reasons for this 
determination in the Federal Register on October 25, 1983 (48 FR 
49244). This assertion was upheld in the courts of the Ninth Circuit 
(Douglas County v. Babbitt, 48 F.3d 1495 (9th Cir. Ore. 1995), cert. 
denied 116 S. Ct. 698 (1996)).

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994, 
``Government-to-Government Relations with Native American Tribal 
Governments'' (59 FR 22951), Executive Order 13175, and the Department 
of Interior's manual at 512 DM 2, we readily acknowledge our 
responsibility to communicate meaningfully with recognized Federal 
Tribes on a government-to-government basis. We have determined that 
there are no Tribal lands occupied at the time of listing that contain 
the features essential for the conservation of the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle 
beetle. Therefore, critical habitat for these species has not been 
proposed for designation on Tribal lands.

References Cited

    A complete list of all references cited in this rulemaking is 
available upon request from the Supervisor, Austin Ecological Services 
Office (see ADDRESSES section above).

Author(s)

    The primary authors of this proposed rule are staff of the 
Ecological Services Office in Austin, Texas (see ADDRESSES section 
above).

List of Subjects in 50 CFR Part 17

    Endangered and threatened species, Exports, Imports, Reporting and 
recordkeeping requirements, Transportation.

Proposed Regulation Promulgation

    Accordingly, we propose to amend part 17, subchapter B of chapter 
I, title 50 of the Code of Federal Regulations, as set forth below:

PART 17--[AMENDED]

    1. The authority citation for part 17 continues to read as follows:

    Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C. 
4201-4245; Pub. L. 99-625, 100 Stat. 3500; unless otherwise noted.

    2. Amend Sec.  17.11(h), the List of Endangered and Threatened 
Wildlife, as follows:
    a. Under ``INSECTS,'' revise the entries for ``Beetle, Comal 
Springs dryopid'' and ``Beetle, Comal Springs riffle'' to read as set 
forth below; and
    b. Under ``CRUSTACEANS,'' revise the entry for ``Amphipod, Peck's 
cave'' to read as set forth below.


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------
                       Species                                                    Vertebrate
------------------------------------------------------                         population where                       When    Critical
                                                          Historic range         endangered or          Status       listed    habitat    Special rules
           Common name              Scientific name                               threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
 
                                                                      * * * * * * *
INSECTS
Beetle, Comal Springs dryopid...  Stygoparnus          U.S.A.(TX)..........  NA..................  E..............      629    17.95(i)  NA
                                   comalensis.
Beetle, Comal Springs riffle....  Heterelmis           U.S.A.(TX)..........  NA..................  E..............      629    17.95(i)  NA
                                   comalensis.
CRUSTACEANS
 
                                                                      * * * * * * *
Amphipod, Peck's cave...........  Stygobromus          U.S.A.(TX)..........  NA..................  E..............      629    17.95(h)  NA
                                   (=Stygonectes)
                                   pecki.
 
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------

    3. Amend Sec.  17.95 as follows:
    a. In paragraph (h), add an entry for ``Peck's cave amphipod 
(Stygobromus pecki)'', in the same alphabetical order in which the 
species appears in the table at 50 CFR 17.11(h), to read as set forth 
below; and
    b. In paragraph (i), add entries for ``Comal Springs dryopid beetle 
(Stygoparnus comalensis)'' and ``Comal Springs riffle beetle 
(Heterelmis comalensis)'', in the same alphabetical order in which 
these species appear in the table at 50 CFR 17.11(h), to read as set 
forth below.


Sec.  17.95  Critical habitat--fish and wildlife.

* * * * *
    (h) Crustaceans.
* * * * *
    Peck's cave amphipod (Stygobromus pecki)
    (1) Critical habitat units are depicted for Comal County, Texas, on 
the maps below.
    (2) The primary constituent elements of critical habitat for Peck's 
cave amphipod are the habitat components that provide:
    (i) High-quality water with pollutant levels of soaps, detergents, 
heavy metals, pesticides, fertilizer nutrients, petroleum hydrocarbons, 
and semi-volatile compounds such as industrial cleaning agents no 
greater than those documented to currently exist and including:
    (A) Low salinity with total dissolved solids that generally range 
from 307 to 368 mg/L; and
    (B) Low turbidity that generally is less than 5 NTUs;
    (C) Aquifer water temperatures that range from approximately 68 to 
75 [deg]F (20 to 24 [deg]C); and
    (ii) Food supply for the Peck's cave amphipod that includes, but is 
not limited to, detritus (decomposed materials), leaf litter, and 
decaying roots.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, and roads) and the surface

[[Page 40602]]

on which they are located that exist on the effective date of this rule 
and do not contain one or more of the primary constituent elements. 
Where lakes are proposed, critical habitat does not include the lake 
bottom beyond 50 feet from the spring outlet.
    (4) Critical habitat map units. Data layers defining map units were 
created by using ArcGIS. All coordinates are UTM zone 14 coordinate 
pairs, referenced to North American Horizontal Datum 1983. Coordinates 
were derived from 2004 digital orthophotographs. All acreage and 
mileage calculations were performed using GIS.

    (5) Note: Index map (Map 1) follows:

BILLING CODE 4310-55-P

[[Page 40603]]

[GRAPHIC] [TIFF OMITTED] TP17JY06.001

    (6) Comal Springs Unit, Comal County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N) : 583387, 3287251; 583392, 3287264; 
583405, 3287280; 583404, 3287290; 583407, 3287301; 583414, 3287307; 
583425, 3287308; 583425, 3287320; 583433, 3287328; 583444, 3287330; 
583454, 3287325; 583463, 3287301; 583482, 3287272; 583486, 3287286; 
583501, 3287296; 583520, 3287314; 583547, 3287326; 583557, 3287333; 
583572, 3287335; 583586, 3287342; 583567, 3287387;

[[Page 40604]]

583560, 3287408; 583559, 3287423; 583534, 3287403; 583499, 3287359; 
583491, 3287347; 583484, 3287340; 583471, 3287334; 583461, 3287334; 
583452, 3287340; 583450, 3287350; 583454, 3287364; 583465, 3287374; 
583494, 3287415; 583521, 3287443; 583526, 3287453; 583563, 3287477; 
583589, 3287503; 583613, 3287519; 583643, 3287547; 583662, 3287561; 
583719, 3287617; 583759, 3287669; 583780, 3287701; 583811, 3287743; 
583833, 3287764; 583848, 3287784; 583892, 3287826; 583911, 3287850; 
583970, 3287907; 584008, 3287938; 584047, 3287963; 584055, 3287964; 
584065, 3287960; 584073, 3287948; 584074, 3287941; 584081, 3287952; 
584131, 3288011; 584164, 3288044; 584183, 3288062; 584197, 3288071; 
584216, 3288093; 584236, 3288110; 584258, 3288138; 584284, 3288161; 
584325, 3288209; 584343, 3288223; 584364, 3288233; 584375, 3288243; 
584386, 3288244; 584401, 3288234; 584403, 3288218; 584433, 3288201; 
584437, 3288193; 584436, 3288184; 584416, 3288167; 584405, 3288167; 
584375, 3288184; 584365, 3288180; 584344, 3288156; 584329, 3288131; 
584320, 3288125; 584298, 3288103; 584273, 3288067; 584204, 3287997; 
584187, 3287985; 584176, 3287973; 584152, 3287943; 584147, 3287933; 
584105, 3287880; 584080, 3287862; 584049, 3287844; 584026, 3287815; 
584021, 3287805; 584013, 3287798; 584009, 3287787; 583999, 3287775; 
583971, 3287751; 583947, 3287735; 583927, 3287725; 583920, 3287718; 
583890, 3287704; 583850, 3287673; 583845, 3287665; 583851, 3287662; 
583860, 3287650; 583865, 3287640; 583865, 3287629; 583863, 3287622; 
583854, 3287609; 583840, 3287600; 583836, 3287584; 583829, 3287576; 
583838, 3287552; 583841, 3287535; 583841, 3287520; 583835, 3287501; 
583804, 3287452; 583790, 3287435; 583766, 3287416; 583727, 3287406; 
583706, 3287406; 583695, 3287398; 583686, 3287370; 583699, 3287298; 
583698, 3287288; 583694, 3287282; 583617, 3287257; 583610, 3287258; 
583605, 3287262; 583597, 3287280; 583584, 3287277; 583565, 3287270; 
583541, 3287255; 583534, 3287244; 583518, 3287233; 583510, 3287211; 
583496, 3287192; 583480, 3287183; 583459, 3287177; 583436, 3287178; 
583419, 3287184; 583400, 3287198; 583396, 3287205; 583387, 3287251.

    (ii) Note: Comal Springs Unit (Map 2) follows:


[[Page 40605]]


[GRAPHIC] [TIFF OMITTED] TP17JY06.002

    (7) Hueco Springs Unit, Comal County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N) : 583113, 3292498; 583114, 3292498; 
583115, 3292498;

[[Page 40606]]

583116, 3292498; 583117, 3292498; 583118, 3292497; 583119, 3292497; 
583120, 3292497; 583120, 3292496; 583121, 3292496; 583122, 3292495; 
583123, 3292495; 583124, 3292494; 583124, 3292493; 583125, 3292493; 
583126, 3292492; 583126, 3292491; 583127, 3292490; 583127, 3292489; 
583127, 3292489; 583128, 3292488; 583128, 3292487; 583128, 3292486; 
583128, 3292485; 583128, 3292484; 583128, 3292483; 583128, 3292482; 
583128, 3292481; 583128, 3292480; 583128, 3292479; 583128, 3292478; 
583127, 3292477; 583127, 3292477; 583127, 3292476; 583126, 3292475; 
583126, 3292474; 583125, 3292473; 583124, 3292473; 583124, 3292472; 
583123, 3292471; 583122, 3292471; 583122, 3292470; 583121, 3292470; 
583120, 3292469; 583119, 3292469; 583118, 3292468; 583117, 3292468; 
583116, 3292468; 583115, 3292468; 583114, 3292468; 583113, 3292468; 
583112, 3292468; 583111, 3292468; 583111, 3292468; 583110, 3292468; 
583109, 3292468; 583108, 3292469; 583107, 3292469; 583106, 3292470; 
583105, 3292470; 583104, 3292471; 583104, 3292471; 583103, 3292472; 
583102, 3292472; 583102, 3292473; 583101, 3292474; 583100, 3292475; 
583100, 3292475; 583100, 3292476; 583099, 3292477; 583099, 3292478; 
583099, 3292479; 583098, 3292480; 583098, 3292481; 583098, 3292482; 
583098, 3292483; 583098, 3292484; 583098, 3292485; 583098, 3292486; 
583098, 3292487; 583099, 3292488; 583099, 3292488; 583099, 3292489; 
583100, 3292490; 583100, 3292491; 583101, 3292492; 583101, 3292493; 
583102, 3292493; 583103, 3292494; 583103, 3292495; 583104, 3292495; 
583105, 3292496; 583106, 3292496; 583107, 3292497; 583108, 3292497; 
583108, 3292497; 583109, 3292498; 583110, 3292498; 583111, 3292498; 
583112, 3292498; 583113, 3292498.
    (ii) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 583132, 3292420; 583133, 3292421; 
583133, 3292421; 583133, 3292422; 583134, 3292423; 583134, 3292424; 
583134, 3292425; 583135, 3292426; 583136, 3292426; 583136, 3292427; 
583137, 3292428; 583138, 3292428; 583138, 3292429; 583139, 3292430; 
583140, 3292430; 583141, 3292430; 583142, 3292431; 583143, 3292431; 
583143, 3292431; 583144, 3292432; 583145, 3292432; 583146, 3292432; 
583147, 3292432; 583148, 3292432; 583149, 3292432; 583150, 3292432; 
583151, 3292432; 583152, 3292431; 583153, 3292431; 583154, 3292431; 
583155, 3292430; 583155, 3292430; 583156, 3292429; 583157, 3292429; 
583158, 3292428; 583158, 3292427; 583159, 3292427; 583160, 3292426; 
583160, 3292425; 583161, 3292424; 583161, 3292423; 583162, 3292422; 
583162, 3292422; 583162, 3292421; 583162, 3292420; 583163, 3292419; 
583163, 3292419; 583163, 3292417; 583163, 3292416; 583163, 3292415; 
583162, 3292414; 583162, 3292421; 583162, 3292412; 583162, 3292411; 
583161, 3292410; 583161, 3292409; 583160, 3292409; 583160, 3292408; 
583159, 3292407; 583159, 3292406; 583158, 3292406; 583157, 3292405; 
583156, 3292404; 583156, 3292404; 583156, 3292403; 583155, 3292402; 
583155, 3292402; 583155, 3292401; 583154, 3292400; 583154, 3292399; 
583153, 3292398; 583152, 3292398; 583152, 3292397; 583151, 3292396; 
583150, 3292396; 583149, 3292395; 583149, 3292395; 583148, 3292394; 
583147, 3292394; 583146, 3292393; 583145, 3292393; 583144, 3292393; 
583143, 3292393; 583142, 3292393; 583141, 3292393; 583140, 3292393; 
583139, 3292393; 583138, 3292393; 583137, 3292393; 583137, 3292393; 
583136, 3292394; 583135, 3292394; 583134, 3292395; 583133, 3292395; 
583132, 3292396; 583132, 3292396; 583131, 3292397; 583130, 3292397; 
583129, 3292398; 583129, 3292399; 583128, 3292400; 583128, 3292400; 
583127, 3292401; 583127, 3292402; 583127, 3292403; 583126, 3292404; 
583126, 3292405; 583126, 3292406; 583126, 3292407; 583126, 3292408; 
583126, 3292409; 583126, 3292410; 583126, 3292411; 583126, 3292412; 
583127, 3292413; 583127, 3292413; 583127, 3292414; 583128, 3292415; 
583128, 3292416; 583129, 3292417; 583129, 3292418; 583130, 3292418; 
583131, 3292419; 583131, 3292420; 583132, 3292420.

    (iii) Note: Hueco Springs Unit (Map 3) follows:


[[Page 40607]]


[GRAPHIC] [TIFF OMITTED] TP17JY06.003

* * * * *
    (i) Insects.
* * * * *
    Comal Springs dryopid beetle (Stygoparnus comalensis)

[[Page 40608]]

    (1) Critical habitat units are depicted for Comal and Hays 
counties, Texas, on the maps below.
    (2) The primary constituent elements of critical habitat for the 
Comal Springs dryopid beetle are the habitat components that provide:
    (i) High-quality water with pollutant levels of soaps, detergents, 
heavy metals, pesticides, fertilizer nutrients, petroleum hydrocarbons, 
and semi-volatile compounds such as industrial cleaning agents no 
greater than those documented to currently exist and including:
    (A) Low salinity with total dissolved solids that generally range 
from 307 to 368 mg/L; and
    (B) Low turbidity that generally is less than 5 NTUs;
    (C) Aquifer water temperatures that range from approximately 68 to 
75 [deg]F (20 to 24 [deg]C);
    (D) A hydrologic regime with turbulent flows that provide adequate 
levels of dissolved oxygen in the general range of 4.0 to 10.0 mg/L for 
respiration of the Comal Springs dryopid beetle; and
    (ii) Food supply for the Comal Springs dryopid beetle that 
includes, but is not limited to, detritus (decomposed materials), leaf 
litter, and decaying roots.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, and roads) and the surface on which they are 
located that exist on the effective date of this rule and do not 
contain one or more of the primary constituent elements. Where lakes 
are proposed, critical habitat does not include the lake bottom beyond 
50 feet from the spring outlet.
    (4) Critical habitat map units. Data layers defining map units were 
created by using ArcGIS. All coordinates are UTM zone 14 coordinate 
pairs, referenced to North American Horizontal Datum 1983. Coordinates 
were derived from 2004 digital orthophotographs. All acreage and 
mileage calculations were performed using GIS.

    (5) Note: Index map of the critical habitat units for Comal 
Springs dryopid beetle and Comal Springs riffle beetle (Map 1) 
follows:


[[Page 40609]]


[GRAPHIC] [TIFF OMITTED] TP17JY06.004

    (6) Comal Springs Unit, Comal County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 583387, 3287251; 583392, 3287264; 
583405, 3287280; 583404, 3287290; 583407, 3287301; 583414, 3287307; 
583425, 3287308; 583425, 3287320; 583433, 3287328; 583444, 3287330; 
583454, 3287325; 583463, 3287301; 583482, 3287272; 583486, 3287286; 
583501, 3287296; 583520, 3287314; 583547, 3287326;

[[Page 40610]]

583557, 3287333; 583572, 3287335; 583586, 3287342; 583567, 3287387; 
583560, 3287408; 583559, 3287423; 583534, 3287403; 583499, 3287359; 
583491, 3287347; 583484, 3287340; 583471, 3287334; 583461, 3287334; 
583452, 3287340; 583450, 3287350; 583454, 3287364; 583465, 3287374; 
583494, 3287415; 583521, 3287443; 583526, 3287453; 583563, 3287477; 
583589, 3287503; 583613, 3287519; 583643, 3287547; 583662, 3287561; 
583719, 3287617; 583759, 3287669; 583780, 3287701; 583811, 3287743; 
583833, 3287764; 583848, 3287784; 583892, 3287826; 583911, 3287850; 
583970, 3287907; 584008, 3287938; 584047, 3287963; 584055, 3287964; 
584065, 3287960; 584073, 3287948; 584074, 3287941; 584081, 3287952; 
584131, 3288011; 584164, 3288044; 584183, 3288062; 584197, 3288071; 
584216, 3288093; 584236, 3288110; 584258, 3288138; 584284, 3288161; 
584325, 3288209; 584343, 3288223; 584364, 3288233; 584375, 3288243; 
584386, 3288244; 584401, 3288234; 584403, 3288218; 584433, 3288201; 
584437, 3288193; 584436, 3288184; 584416, 3288167; 584405, 3288167; 
584375, 3288184; 584365, 3288180; 584344, 3288156; 584329, 3288131; 
584320, 3288125; 584298, 3288103; 584273, 3288067; 584204, 3287997; 
584187, 3287985; 584176, 3287973; 584152, 3287943; 584147, 3287933; 
584105, 3287880; 584080, 3287862; 584049, 3287844; 584026, 3287815; 
584021, 3287805; 584013, 3287798; 584009, 3287787; 583999, 3287775; 
583971, 3287751; 583947, 3287735; 583927, 3287725; 583920, 3287718; 
583890, 3287704; 583850, 3287673; 583845, 3287665; 583851, 3287662; 
583860, 3287650; 583865, 3287640; 583865, 3287629; 583863, 3287622; 
583854, 3287609; 583840, 3287600; 583836, 3287584; 583829, 3287576; 
583838, 3287552; 583841, 3287535; 583841, 3287520; 583835, 3287501; 
583804, 3287452; 583790, 3287435; 583766, 3287416; 583727, 3287406; 
583706, 3287406; 583695, 3287398; 583686, 3287370; 583699, 3287298; 
583698, 3287288; 583694, 3287282; 583617, 3287257; 583610, 3287258; 
583605, 3287262; 583597, 3287280; 583584, 3287277; 583565, 3287270; 
583541, 3287255; 583534, 3287244; 583518, 3287233; 583510, 3287211; 
583496, 3287192; 583480, 3287183; 583459, 3287177; 583436, 3287178; 
583419, 3287184; 583400, 3287198; 583396, 3287205; 583387, 3287251.

    (ii) Note: Comal Springs Unit (Map 2) follows:


[[Page 40611]]


[GRAPHIC] [TIFF OMITTED] TP17JY06.005

    (7) Fern Bank Springs Unit, Hays County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 595131, 3317374; 595131, 3317375; 
595132, 3317376;

[[Page 40612]]

595132, 3317377; 595132, 3317378; 595132, 3317379; 595133, 3317380; 
595133, 3317381; 595133, 3317382; 595134, 3317383; 595135, 3317383; 
595135, 3317384; 595136, 3317385; 595137, 3317386; 595137, 3317386; 
595138, 3317387; 595139, 3317387; 595140, 3317388; 595141, 3317388; 
595141, 3317388; 595168, 3317398; 595181, 3317411; 595198, 3317428; 
595198, 3317428; 595199, 3317429; 595199, 3317430; 595200, 3317430; 
595201, 3317431; 595202, 3317431; 595203, 3317432; 595204, 3317432; 
595205, 3317432; 595206, 3317432; 595207, 3317433; 595208, 3317433; 
595209, 3317433; 595210, 3317433; 595211, 3317433; 595212, 3317433; 
595213, 3317432; 595214, 3317432; 595214, 3317432; 595215, 3317431; 
595216, 3317431; 595217, 3317430; 595218, 3317430; 595219, 3317429; 
595219, 3317428; 595220, 3317428; 595221, 3317427; 595237, 3317406; 
595237, 3317406; 595238, 3317405; 595238, 3317404; 595239, 3317404; 
595239, 3317403; 595239, 3317402; 595240, 3317401; 595240, 3317400; 
595240, 3317400; 595240, 3317399; 595240, 3317398; 595240, 3317397; 
595240, 3317396; 595240, 3317395; 595240, 3317394; 595240, 3317394; 
595240, 3317393; 595239, 3317392; 595239, 3317391; 595239, 3317390; 
595238, 3317389; 595238, 3317388; 595237, 3317388; 595237, 3317388; 
595223, 3317369; 595223, 3317369; 595222, 3317368; 595221, 3317367; 
595221, 3317366; 595220, 3317366; 595219, 3317365; 595218, 3317365; 
595217, 3317364; 595217, 3317364; 595173, 3317343; 595173, 3317343; 
595172, 3317343; 595171, 3317342; 595170, 3317342; 595169, 3317342; 
595168, 3317342; 595167, 3317342; 595166, 3317342; 595165, 3317342; 
595164, 3317342; 595163, 3317342; 595162, 3317343; 595146, 3317347; 
595146, 3317348; 595145, 3317348; 595144, 3317348; 595143, 3317349; 
595142, 3317349; 595141, 3317350; 595141, 3317350; 595141, 3317350; 
595140, 3317351; 595139, 3317352; 595139, 3317352; 595139, 3317353; 
595138, 3317353; 595138, 3317354; 595137, 3317355; 595137, 3317356; 
595136, 3317357; 595136, 3317357; 595132, 3317369; 595132, 3317370; 
595132, 3317370; 595132, 3317371; 595132, 3317372; 595131, 3317373; 
595131, 3317374.

    (ii) Note: Fern Bank Springs Unit (Map 3) follows:


[[Page 40613]]


[GRAPHIC] [TIFF OMITTED] TP17JY06.006


[[Page 40614]]


* * * * *
    Comal Springs riffle beetle (Heterelmis comalensis)
    (1) Critical habitat units are depicted for Comal and Hays 
counties, Texas, on the maps below.
    (2) The primary constituent elements of critical habitat for Comal 
Springs riffle beetle are the habitat components that provide:
    (i) High-quality water with pollutant levels of soaps, detergents, 
heavy metals, pesticides, fertilizer nutrients, petroleum hydrocarbons, 
and semi-volatile compounds such as industrial cleaning agents no 
greater than those documented to currently exist and including:
    (A) Low salinity with total dissolved solids that generally range 
from 307 to 368 mg/L; and
    (B) Low turbidity that generally is less than 5 NTUs;
    (C) Aquifer water temperatures that range from approximately 68 to 
75 [deg]F (20 to 24 [deg]C);
    (D) A hydrologic regime with turbulent flows that provide adequate 
levels of dissolved oxygen in the general range of 4.0 to 10.0 mg/L for 
respiration of the Comal Springs riffle beetle; and
    (ii) Food supply for the Comal Springs riffle beetle that includes, 
but is not limited to, detritus (decomposed materials), leaf litter, 
and decaying roots.
    (iii) Bottom substrate in surface water habitat of the Comal 
Springs riffle beetle that is composed of sediment-free gravel and 
cobble ranging in size from 0.3 to 5.0 inches (8 to 128 millimeters).
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, and roads) and the surface on which they are 
located that exist on the effective date of this rule and do not 
contain one or more of the primary constituent elements. Where lakes 
are proposed, critical habitat does not include the lake bottom beyond 
50 feet from the spring outlet.
    (4) Critical habitat map units. Data layers defining map units were 
created by using ArcGIS. All coordinates are UTM zone 14 coordinate 
pairs, referenced to North American Horizontal Datum 1983. Coordinates 
were derived from 2004 digital orthophotographs. All acreage and 
mileage calculations were performed using GIS.

    (5) Note: Index map of the critical habitat units for Comal 
Springs riffle beetle (Map 1) follows:


[[Page 40615]]


[GRAPHIC] [TIFF OMITTED] TP17JY06.007

    (6) Comal Springs Unit, Comal County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 583420, 3287293; 583423, 3287293; 
583426, 3287293; 583428, 3287290; 583429, 3287285; 583428, 3287280; 
583426, 3287273; 583422, 3287268; 583416, 3287259; 583415, 3287255; 
583415, 3287249; 583417, 3287238; 583418, 3287233; 583419, 3287228; 
583418, 3287222; 583421, 3287221; 583427, 3287216;

[[Page 40616]]

583429, 3287207; 583435, 3287204; 583442, 3287203; 583455, 3287203; 
583464, 3287203; 583468, 3287205; 583475, 3287209; 583479, 3287213; 
583479, 3287217; 583483, 3287224; 583486, 3287232; 583490, 3287246; 
583491, 3287248; 583485, 3287247; 583481, 3287245; 583476, 3287243; 
583471, 3287241; 583461, 3287239; 583460, 3287242; 583460, 3287248; 
583459, 3287255; 583459, 3287261; 583458, 3287266; 583455, 3287272; 
583455, 3287277; 583452, 3287282; 583449, 3287284; 583446, 3287288; 
583445, 3287295; 583441, 3287307; 583439, 3287314; 583443, 3287315; 
583444, 3287309; 583446, 3287303; 583449, 3287293; 583450, 3287291; 
583453, 3287288; 583457, 3287284; 583461, 3287278; 583466, 3287271; 
583468, 3287263; 583469, 3287255; 583470, 3287251; 583480, 3287257; 
583484, 3287256; 583488, 3287254; 583492, 3287253; 583493, 3287254; 
583496, 3287255; 583500, 3287257; 583503, 3287258; 583507, 3287260; 
583509, 3287261; 583509, 3287262; 583509, 3287265; 583508, 3287266; 
583504, 3287270; 583502, 3287270; 583499, 3287270; 583497, 3287271; 
583497, 3287273; 583498, 3287276; 583500, 3287277; 583502, 3287279; 
583505, 3287281; 583508, 3287282; 583512, 3287285; 583516, 3287291; 
583521, 3287294; 583525, 3287298; 583528, 3287301; 583531, 3287303; 
583535, 3287305; 583540, 3287306; 583544, 3287309; 583551, 3287311; 
583556, 3287313; 583560, 3287317; 583563, 3287319; 583567, 3287320; 
583571, 3287320; 583575, 3287320; 583578, 3287321; 583580, 3287322; 
583583, 3287324; 583587, 3287326; 583592, 3287328; 583595, 3287329; 
583597, 3287330; 583600, 3287331; 583603, 3287332; 583604, 3287333; 
583605, 3287337; 583605, 3287340; 583604, 3287344; 583601, 3287346; 
583598, 3287353; 583593, 3287363; 583589, 3287371; 583587, 3287378; 
583581, 3287392; 583580, 3287400; 583575, 3287411; 583574, 3287420; 
583575, 3287430; 583575, 3287435; 583575, 3287438; 583575, 3287441; 
583574, 3287442; 583573, 3287442; 583572, 3287442; 583569, 3287441; 
583567, 3287442; 583563, 3287442; 583558, 3287441; 583553, 3287437; 
583549, 3287435; 583542, 3287429; 583539, 3287428; 583536, 3287425; 
583533, 3287420; 583524, 3287415; 583516, 3287405; 583510, 3287398; 
583505, 3287392; 583499, 3287383; 583494, 3287378; 583486, 3287368; 
583482, 3287361; 583479, 3287356; 583475, 3287353; 583467, 3287349; 
583465, 3287349; 583466, 3287355; 583468, 3287356; 583470, 3287357; 
583471, 3287359; 583473, 3287361; 583475, 3287362; 583479, 3287367; 
583485, 3287377; 583491, 3287386; 583498, 3287395; 583506, 3287406; 
583509, 3287407; 583511, 3287412; 583523, 3287423; 583533, 3287434; 
583535, 3287437; 583537, 3287442; 583549, 3287449; 583558, 3287455; 
583565, 3287461; 583571, 3287464; 583576, 3287468; 583584, 3287478; 
583598, 3287491; 583610, 3287498; 583623, 3287507; 583635, 3287519; 
583653, 3287536; 583672, 3287549; 583685, 3287562; 583697, 3287574; 
583731, 3287607; 583739, 3287618; 583753, 3287634; 583761, 3287645; 
583772, 3287660; 583784, 3287679; 583792, 3287692; 583809, 3287716; 
583823, 3287733; 583844, 3287754; 583859, 3287773; 583870, 3287784; 
583883, 3287797; 583903, 3287816; 583913, 3287829; 583922, 3287839; 
583933, 3287849; 583941, 3287857; 583951, 3287867; 583961, 3287878; 
583971, 3287886; 583980, 3287896; 583991, 3287905; 584005, 3287917; 
584017, 3287926; 584024, 3287931; 584038, 3287941; 584049, 3287948; 
584052, 3287949; 584055, 3287948; 584056, 3287945; 584059, 3287941; 
584059, 3287937; 584055, 3287935; 584054, 3287932; 584055, 3287929; 
584060, 3287926; 584067, 3287926; 584071, 3287924; 584078, 3287920; 
584081, 3287921; 584085, 3287929; 584093, 3287942; 584108, 3287958; 
584116, 3287970; 584128, 3287984; 584142, 3288000; 584150, 3288007; 
584157, 3288014; 584163, 3288021; 584169, 3288027; 584174, 3288033; 
584181, 3288039; 584187, 3288044; 584192, 3288050; 584207, 3288060; 
584216, 3288071; 584227, 3288082; 584239, 3288093; 584247, 3288099; 
584251, 3288104; 584255, 3288109; 584261, 3288116; 584265, 3288121; 
584270, 3288128; 584277, 3288132; 584282, 3288138; 584289, 3288144; 
584296, 3288151; 584303, 3288161; 584313, 3288171; 584318, 3288178; 
584328, 3288188; 584336, 3288198; 584342, 3288201; 584347, 3288204; 
584349, 3288207; 584352, 3288210; 584357, 3288212; 584360, 3288215; 
584366, 3288217; 584371, 3288219; 584374, 3288221; 584378, 3288225; 
584382, 3288229; 584388, 3288225; 584388, 3288224; 584388, 3288220; 
584388, 3288216; 584388, 3288214; 584389, 3288211; 584389, 3288209; 
584395, 3288205; 584401, 3288203; 584422, 3288191; 584411, 3288181; 
584393, 3288192; 584382, 3288198; 584376, 3288200; 584371, 3288199; 
584363, 3288197; 584355, 3288191; 584348, 3288183; 584340, 3288175; 
584332, 3288165; 584326, 3288157; 584319, 3288147; 584316, 3288143; 
584317, 3288141; 584316, 3288140; 584314, 3288141; 584309, 3288136; 
584303, 3288129; 584286, 3288113; 584277, 3288100; 584269, 3288089; 
584261, 3288077; 584253, 3288071; 584240, 3288057; 584236, 3288052; 
584228, 3288045; 584219, 3288035; 584210, 3288026; 584203, 3288019; 
584193, 3288008; 584183, 3288002; 584176, 3287996; 584169, 3287987; 
584165, 3287984; 584158, 3287974; 584150, 3287966; 584139, 3287951; 
584135, 3287942; 584127, 3287933; 584114, 3287915; 584105, 3287905; 
584094, 3287891; 584082, 3287884; 584072, 3287875; 584059, 3287867; 
584047, 3287862; 584038, 3287855; 584033, 3287848; 584025, 3287840; 
584019, 3287830; 584016, 3287827; 584016, 3287827; 584013, 3287824; 
584011, 3287820; 584009, 3287814; 584005, 3287811; 584000, 3287806; 
583996, 3287795; 583988, 3287786; 583982, 3287780; 583972, 3287771; 
583962, 3287764; 583950, 3287757; 583939, 3287748; 583928, 3287743; 
583917, 3287737; 583917, 3287737; 583912, 3287731; 583895, 3287724; 
583881, 3287717; 583872, 3287708; 583860, 3287701; 583847, 3287692; 
583838, 3287683; 583829, 3287669; 583828, 3287663; 583830, 3287659; 
583835, 3287653; 583840, 3287651; 583843, 3287647; 583847, 3287642; 
583850, 3287636; 583850, 3287630; 583847, 3287625; 583842, 3287619; 
583836, 3287616; 583829, 3287611; 583824, 3287603; 583823, 3287597; 
583822, 3287591; 583820, 3287588; 583814, 3287587; 583813, 3287583; 
583812, 3287580; 583814, 3287575; 583815, 3287570; 583817, 3287565; 
583820, 3287558; 583824, 3287548; 583826, 3287541; 583826, 3287534; 
583826, 3287522; 583823, 3287515; 583821, 3287507; 583813, 3287493; 
583807, 3287485; 583803, 3287481; 583803, 3287478; 583799, 3287472; 
583792, 3287462; 583779, 3287446; 583769, 3287437; 583757, 3287428; 
583753, 3287427; 583746, 3287426; 583734, 3287423; 583725, 3287421; 
583715, 3287420; 583709, 3287421; 583702, 3287421; 583696, 3287418; 
583689, 3287413; 583683, 3287407; 583679, 3287400; 583677, 3287393; 
583674, 3287383; 583671, 3287371; 583672, 3287360; 583675, 3287341; 
583678, 3287324; 583680, 3287312; 583684, 3287297; 583684, 3287293; 
583616, 3287272; 583615, 3287275; 583610, 3287289; 583606, 3287294; 
583601, 3287295; 583595, 3287296; 583592, 3287294; 583580, 3287292; 
583569, 3287288; 583557, 3287283; 583548, 3287276; 583539, 3287271; 
583531, 3287267; 583525, 3287260; 583523, 3287255; 583517, 3287253;

[[Page 40617]]

583513, 3287248; 583507, 3287243; 583502, 3287236; 583500, 3287228; 
583497, 3287219; 583493, 3287213; 583486, 3287203; 583474, 3287197; 
583458, 3287192; 583447, 3287192; 583439, 3287193; 583434, 3287196; 
583430, 3287198; 583428, 3287197; 583424, 3287198; 583422, 3287201; 
583419, 3287203; 583415, 3287205; 583411, 3287209; 583409, 3287221; 
583406, 3287230; 583404, 3287240; 583402, 3287251; 583405, 3287256; 
583408, 3287259; 583412, 3287263; 583417, 3287270; 583420, 3287276; 
583422, 3287279; 583421, 3287282; 583419, 3287285; 583419, 3287288; 
583420, 3287293.

    (ii) Note: Comal Springs Unit (Map 2) follows:


[[Page 40618]]


[GRAPHIC] [TIFF OMITTED] TP17JY06.008

    (7) San Marcos Springs Unit, Hays County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 602869, 3307092; 602870, 3307100; 
602877, 3307131;

[[Page 40619]]

602892, 3307172; 602926, 3307215; 602936, 3307229; 602942, 3307237; 
602945, 3307243; 602957, 3307286; 603007, 3307329; 603072, 3307386; 
603154, 3307462; 603158, 3307463; 603166, 3307466; 603175, 3307465; 
603186, 3307473; 603219, 3307486; 603258, 3307508; 603288, 3307526; 
603307, 3307541; 603317, 3307544; 603326, 3307539; 603329, 3307527; 
603319, 3307512; 603251, 3307456; 603234, 3307439; 603224, 3307433; 
603218, 3307419; 603206, 3307412; 603192, 3307406; 603175, 3307418; 
603170, 3307419; 603153, 3307414; 603144, 3307404; 603141, 3307389; 
603145, 3307379; 603147, 3307369; 603152, 3307352; 603141, 3307339; 
603135, 3307339; 603124, 3307337; 603120, 3307336; 603116, 3307335; 
603114, 3307325; 603109, 3307318; 603105, 3307315; 603104, 3307314; 
603100, 3307310; 603024, 3307239; 603023, 3307240; 603019, 3307237; 
603017, 3307233; 603026, 3307203; 603035, 3307187; 603038, 3307178; 
603038, 3307166; 603033, 3307148; 603027, 3307138; 603018, 3307123; 
603002, 3307117; 602983, 3307109; 602968, 3307097; 602962, 3307105; 
602962, 3307105; 602965, 3307112; 602963, 3307116; 602958, 3307119; 
602954, 3307123; 602946, 3307126; 602938, 3307129; 602928, 3307129; 
602921, 3307129; 602913, 3307128; 602896, 3307105; 602894, 3307101; 
602887, 3307097; 602881, 3307091; 602883, 3307087; 602877, 3307082; 
602875, 3307084; 602872, 3307087; 602869, 3307092.

    (ii) Note: San Marcos Springs Unit (Map 3) follows:


[[Page 40620]]


[GRAPHIC] [TIFF OMITTED] TP17JY06.009


[[Page 40621]]


* * * * *

    Dated: July 7, 2006.
Matt Hogan,
Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. 06-6182 Filed 7-14-06; 8:45 am]
BILLING CODE 4310-55-C