[Federal Register: November 15, 2007 (Volume 72, Number 220)] [Rules and Regulations] [Page 64285-64340] From the Federal Register Online via GPO Access [wais.access.gpo.gov] [DOCID:fr15no07-21] [[Page 64285]] ----------------------------------------------------------------------- Part II Department of the Interior ----------------------------------------------------------------------- Fish and Wildlife Service ----------------------------------------------------------------------- 50 CFR Part 17 Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Five Endangered and Two Threatened Mussels in Four Northeast Gulf of Mexico Drainages; Final Rule [[Page 64286]] ----------------------------------------------------------------------- DEPARTMENT OF THE INTERIOR Fish and Wildlife Service 50 CFR Part 17 RIN 1018-AU87 Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Five Endangered and Two Threatened Mussels in Four Northeast Gulf of Mexico Drainages AGENCY: Fish and Wildlife Service, Interior. ACTION: Final rule. ----------------------------------------------------------------------- SUMMARY: We, the U.S. Fish and Wildlife Service (Service), are designating critical habitat for the endangered fat threeridge (Amblema neislerii), shinyrayed pocketbook (Lampsilis subangulata), Gulf moccasinshell (Medionidus penicillatus), Ochlockonee moccasinshell (Medionidus simpsonianus), and oval pigtoe (Pleurobema pyriforme), and the threatened Chipola slabshell (Elliptio chipolaensis) and purple bankclimber (Elliptoideus sloatianus) (collectively referred to as the seven mussels) under the Endangered Species Act of 1973, as amended (Act). The total length of streams designated is approximately 1,185.9 river miles (river mi) (1,908.5 river kilometers (river km)). The critical habitat is located in Houston and Russell counties, Alabama; in Alachua, Bay, Bradford, Calhoun, Columbia, Franklin, Gadsden, Gulf, Jackson, Leon, Liberty, Union, Wakulla, and Washington counties, Florida; and in Baker, Calhoun, Coweta, Crawford, Crisp, Decatur, Dooly, Dougherty, Early, Fayette, Grady, Lee, Macon, Marion, Meriwether, Miller, Mitchell, Peach, Pike, Schley, Spalding, Sumter, Talbot, Taylor, Terrell, Thomas, Upson, Webster, and Worth counties, Georgia. DATES: This rule becomes effective on December 17, 2007. ADDRESSES: Comments and materials received, as well as supporting documentation used in the preparation of this final rule, will be available for public inspection, by appointment, during normal business hours, at the U.S. Fish and Wildlife Service, Panama City Ecological Services Office, 1601 Balboa Avenue, Panama City, FL 32405 (telephone 850-769-0552). The final rule, economic analysis, and maps will also be available via the Internet at http://www.fws.gov/panamacity/. FOR FURTHER INFORMATION CONTACT: Gail Carmody, Field Supervisor, Panama City Ecological Services Office, 1601 Balboa Avenue, Panama City, FL 32405; telephone 850-769-0552; facsimile 850-763-2177. If you use a telecommunications device for the deaf (TDD), call the Federal Information Relay Service (FIRS) at 800-877-8339. SUPPLEMENTARY INFORMATION: Background It is our intent to discuss only those topics directly relevant to the designation of critical habitat in this final rule. For additional information on the seven mussels, refer to the final listing rule published in the Federal Register on March 16, 1998 (63 FR 12664), the final recovery plan that was approved September 19, 2003 (available from our Panama City, Florida Office or online at http://www.fws.gov/endangered/recovery/Index.html#plans ), and the proposed critical habitat rule published in the Federal Register on June 6, 2006 (71 FR 32746). The shinyrayed pocketbook was listed as federally endangered under the scientific name Lampsilis subangulata. The shinyrayed pocketbook and three other Lampsilis species are now assigned to the newly recognized genus Hamiota (Roe and Hartfield 2005, p. 1). The Service intends to implement the name change in a separate rulemaking. In November 2006, an Auburn University scientist working under contract for the Service identified eight mussels as shinyrayed pocketbooks that he found in a segment of Econfina Creek (M. Gangloff, personal communication November 3, 2006). This stream segment is within the area designated in this rule as critical habitat for the Gulf moccasinshell and oval pigtoe. If the identification is correct, this find represents the first record of the shinyrayed pocketbook in the Econfina Creek Basin, which was previously known only from the Apalachicola- Chattahoochee-Flint (ACF) and Ochlockonee basins. The Service intends to conduct further surveys to confirm whether the species is in Econfina Creek and, if so, to estimate its range and abundance in the basin. In this rule, we do not designate Econfina Creek as critical habitat for the shinyrayed pocketbook. Previous Federal Actions On March 15, 2004, the Center for Biological Diversity (Center) filed a lawsuit against the Department of the Interior and the Service (Civil Action No. 1:04 CV-0729-GET) challenging the failure to designate critical habitat for the seven mussels. In a settlement agreement dated August 31, 2004, the Service agreed to reevaluate the prudency of critical habitat for the seven mussels and, if prudent, submit a proposed designation of critical habitat to the Federal Register by May 30, 2006, and a final designation by May 30, 2007. On March 7, 2007, the court granted an extension and set the new final designation deadline for October 31, 2007. We published the proposed critical habitat rule for the seven mussels in the Federal Register on June 6, 2006 (71 FR 32746). We accepted public comments on the proposal for 60 days until August 7, 2007. We completed a draft economic analysis (DEA) for the proposed designation on June 6, 2007, and published a notice of availability for this DEA in the Federal Register on June 21, 2007 (72 FR 34215). The public comment period for the DEA was open until August 6, 2007. For more information on previous Federal actions concerning the seven mussels, refer to the proposed critical habitat designation (71 FR 32746, June 6, 2006) and our notice of availability of the draft economic analysis (72 FR 34215, June 21, 2007). This final rule complies with the settlement agreement. Summary of Comments and Recommendations We requested written comments from the public on the proposed designation of critical habitat for the seven mussels in the proposed rule, and again in the subsequent notice of availability (72 FR 34215). On both occasions, we contacted appropriate Federal, State, and local agencies; scientific organizations; and other interested parties and invited them to comment on the proposed rule. Three public hearings were held during the second comment period on July 9, 2007, in Columbus, Georgia, July 10, 2007, in Albany, Georgia, and July 11, 2007, in Tallahassee, Florida. During the first comment period that opened on June 6, 2006, and closed on August 7, 2006, we received comments from 30 entities that directly addressed the proposed critical habitat designation: one from a peer reviewer, 3 from Federal agencies, 16 from State and local governmental agencies, and 10 from organizations or individuals. We received 4 requests for a public hearing, all from entities in the LaGrange and Columbus, Georgia, area. During the second comment period that opened on June 21, 2007, and closed on August 6, 2007, including the three public hearings, we received comments from 25 entities that directly addressed the proposed critical habitat designation or the draft economic analysis: 4 from peer reviewers, 3 from Federal agencies, 7 [[Page 64287]] from State and local governmental agencies, and 11 from organizations or individuals. Of the comments provided during both comment periods, six commenters supported the designation of critical habitat for the seven mussels and nine opposed the designation. Forty commenters provided suggestions or information, but did not indicate support or opposition to the critical habitat designation. We received comments that were grouped into 70 issues specifically relating to the proposed critical habitat designation for the seven mussels, and are addressed in the following summary and incorporated into the final rule as appropriate. Peer Review In accordance with our policy published on July 1, 1994 (59 FR 34270), we solicited expert opinions from seven knowledgeable individuals with scientific expertise that included familiarity with the species, the geographic region in which the species occurs, and conservation biology principles. We received responses from four of the peer reviewers. The peer reviewers generally concurred with our methods and conclusions, and provided additional information, clarifications, and suggestions to improve the final critical habitat rule. We address peer reviewer comments in the following summary and incorporate into the final rule as appropriate. We reviewed all comments received from the peer reviewers and the public for substantive issues and new information regarding critical habitat for the seven mussels, and address them in the following summary. Peer Reviewer Comments (1) Comment: The Service stated in the proposed rule that ``Most of the tributary streams in the four basins that may support one or more of the seven species have never been surveyed.'' This seems to cast doubt on the adequacy of the data used to designate critical habitat. Most streams in this region that are large enough to support these species have been surveyed at least to some extent. Our Response: We acknowledge that a substantial fraction of the unsurveyed tributary streams in the region are probably not large enough to support populations of the seven mussels. However, the drainage area associated with the upstream-most location in most of the occupied watersheds is often quite small (e.g., less than about 5,000 ha (20 mi\2\)), and we have no data for a majority of locations in the four basins that drain areas of this size. Regardless, we have considered all available survey data in our analysis for identifying critical habitat. We designated only where presence is confirmed by surveys. (2) Comment: The designation of critical habitat should consider whether re-establishing populations in streams where a species formerly occurred is necessary to fully recover the species. Our Response: The Act provides for designating areas that are unoccupied at the time of listing when such areas are essential for the conservation of a listed species. We listed the seven mussels based on a substantial decline in range and abundance and threats to their habitats. Our recovery plan (USFWS 2003:76-83) quantifies the amount of range expansion into formerly occupied areas that we believe is necessary to achieve recovery for the five species we listed as endangered. By delineating critical habitat units as the collective extent of occurrence of all seven listed species within a sub-basin, our proposed critical habitat included a stream length that met the recovery plan's geographic range recovery criteria for each of the five endangered species. We do not believe a substantial increase in extent of occurrence is either feasible or necessary for the recovery of the two threatened species, which have experienced a lesser decline in range than the five endangered species. The seven mussels historically occupied overlapping but also different portions of the eleven units, and it is not necessary for each species to occupy all suitable habitat within its designated critical habitat units to achieve recovery. We considered designating units for species that are entirely extirpated from those units but determined that doing so is not essential for their conservation. (3) Comment: Characterizing the stream substrates that are essential to the conservation of the seven mussels as composed of predominantly coarse materials is too simplistic and potentially misleading. Fine sediments (silts and clays) are a natural component of stream substrates in the coastal plain, including substrates used by the seven listed species. In this region, very coarse substrates are often associated with channel scouring and are devoid of mussels. Our Response: We agree that some amount (generally less than 50 percent by dry weight) of fine sediment is a normal component of the substrate that is essential to the conservation of the seven mussels. Coarse sands without any silt or clay, for example, lack cohesiveness and do not appear to support many mussels, including the listed species. By emphasizing the adverse affects of excessive amounts of fine sediments, we may have implied that the seven mussels are altogether intolerant of fine sediments, which is not the case. Therefore, we have revised the substrate primary constituent element (PCE) and our discussion of substrate quality to acknowledge the appropriate role of fine sediments in substrate quality. (4) Comment: The proposed rule stated that the three other species reassigned from the genus Lampsilis to the newly recognized genus Hamiota are not federally listed, but two of these are: H. altilis and H. perovalis. The third, H. australis, is considered a candidate for protection under the Act. Our Response: The comment is correct. We erred in stating that the three other species are not federally listed, and we have revised the text of the final rule accordingly. (5) Comment: Because other portions of the Uchee Creek sub-basin besides those proposed for designation have supported the shinyrayed pocketbook and other listed species as recently as 1973, but have not been surveyed much or at all since then, the rule should designate all portions of this sub-basin below the Fall Line as critical habitat. Our Response: Riverine habitats are dynamic and subject to a variety of threats, which makes survey data about the presence of particular mussel species time-specific. It is not feasible to routinely survey the full range of the seven species, which collectively spans over 1,000 river miles. We chose post-1990 live occurrence records as a criterion for evidence that a site has supported recent occupancy because a great deal of our data comes from a range-wide status survey conducted in 1991 and 1992, shortly before the species were proposed for listing in 1994. Occurrence records from 1973 do not meet the criterion we set for evidence of recent occupancy; therefore, we did not designate other portions of the Uchee Creek sub- basin. Our method of identifying stream segments that meet the criterion of recent occupancy by one or more of the listed species and then delineating units as contiguous groups of these stream segments resulted in designating a total length of stream habitat meets our recovery plan's geographic range recovery criteria for each of the seven mussels (see response to Comment 2). Therefore, we believe that designating additional areas for which we do not have evidence of recent occupancy is not essential to their conservation. Listed species that may occur outside of designated critical habitat still receive protection under the [[Page 64288]] jeopardy standard of section 7 and the take prohibition of section 9 of the Act. (6) Comment: Because Sawhatchee and Kirkland creeks are separated by unsuitable habitat in an impounded section of the Chattahoochee River, these creeks should be designated as separate critical habitat units. Our Response: We have grouped Sawhatchee and Kirkland creeks in the same unit because they share two of three listed species in common and flow unimpeded by fish passage barriers into a common water body. Host fish, such as largemouth bass, could conceivably transport glochidia between these two streams. Comments from States Section 4(i) of the Act states, ``the Secretary shall submit to the State agency a written justification for his failure to adopt regulations consistent with the agency's comments or petition.'' We address comments received from States regarding the proposal to designate critical habitat for the seven mussels below. (7) Comment: The designation is overly broad because it includes areas at high elevations within the lateral boundaries and areas between the upstream and downstream boundaries that do not support the mussels. Our Response: Our regulations allow the inclusive designation of occupied and unoccupied areas in proximity to each other that are each essential to the conservation of a species (50 CFR 424.12(d)). We agree that the adult seven mussels are seldom found at or near the ordinary high water marks in a stream, as this portion of the stream bed is inundated only during relatively high flows; however, we have determined that the entire stream channel between the ordinary high water marks is essential to their conservation as the larval life stage of these mussels while attached to a fish host or drifting in the current could ``occupy'' all habitats that the fish visits or the current takes them, including places at or near the ordinary high water marks during high water conditions. The location of suitable areas for mussel habitat is dependent on fluvial dynamics that occur mostly within the channel up to the ordinary high water marks. A stable stream bank that is laterally adjacent to but vertically above a mussel bed is essential to the viability of the mussel bed. Further, our regulations prescribe the use of reference points and lines as found on standard topographic maps for describing the boundaries of critical habitat (50 CFR 424.12(c)). The ordinary high water marks as defined in the Corps' navigation regulations (33 CFR 329.11) roughly correspond to how river channels are represented on standard topographic maps. We agree also that the adult seven mussels are not found at all locations between the upstream and downstream boundaries given the unit descriptions. However, as with the lateral boundaries, we have determined that the entire stream channel between the upstream and downstream limits is essential to their conservation. Riverine habitats are dynamic, and locations that provide suitable conditions for mussels may shift over time between these upstream and downstream limits. Connectivity between the upstream and downstream limits provides for host fish movement, gametes transport, dispersal into newly suitable habitats, and food items transport. Therefore, we have kept these areas in the designation. (8) Comment: The designation is contrary to the Act because it includes areas that do not contain all of the physical and biological features that the Service determined are essential to the conservation of a listed species and may require special management (PCEs). For example, Unit 8 (Apalachicola River) includes the distributary Swift Slough, which has aggraded (filled with sediment) in recent years and no longer flows continuously. Our Response: Each of the 11 units designated as critical habitat contains all of the PCEs, and each stream segment listed in the unit descriptions contains one or more of the PCEs. Neither the Act nor our regulations require that all portions of a designated critical habitat unit contain all of the PCEs. Mobile animals typically satisfy various life history requirements by relying upon different habitat features in different portions of their range. While juveniles and adults of the seven mussels are relatively immobile animals, their glochidia (larvae) and host fish are not. Dispersal via fish hosts is how the species colonize new areas and is necessary to achieve recovery, although mussels are also sometimes moved into new areas by high-flow events. Mussels will best survive and reproduce in specific areas that consistently provide all of the PCEs, but do not necessarily persist permanently in any one area given the dynamic nature of the riverine environment. Interrupted flow due to the accumulation of sediment in the bed of Swift Slough has recently led to substantial mortality of listed mussels in this stream during periods of low-flow in the Apalachicola River. However, it does not follow that this or any particular area within a critical habitat unit that lacks all of the PCEs cannot be included in a critical habitat unit. Stream bed aggradation in Swift Slough signals the need for special management of the channel stability PCE in at least the Swift Slough portion of Unit 8. While permanently flowing water, channel stability, etc., are features essential to the conservation of the seven mussels in each designated unit, we recognize that some portions of all 11 units have problems with at least one of the PCEs that may require special management or protections. (9) Comment: Florida Fish and Wildlife Conservation Commission personnel found shell material of the listed species in the Brushy Creek ``feeders'' (floodplain distributaries of the Apalachicola River that flow into Brushy Creek). The Service must determine whether the Brushy Creek feeders were likely occupied in 1998 (the time of listing), and if so, designate those streams if they otherwise qualify as critical habitat. Areas like the Brushy Creek feeders, currently unoccupied, should be designated anyway if they are essential for the conservation of the species. Areas like the Brushy Creek feeders are key to the recovery of mussels because they can act as nursery areas and provide for population expansion. Our Response: We relied upon post-1990 live occurrence records to provide evidence that areas were likely occupied at the time of listing, and we have no such evidence for the Brushy Creek feeders. Dead shells found recently in these distributaries, which receive flow directly from a part of the main channel of the Apalachicola River where listed species are known to occur, is not evidence that these streams support the listed species now or at the time of listing. It is more likely that the shells found in the Brushy Creek feeders were transported by currents from the main channel. We believe that areas for which we have no evidence of recent occupancy are not essential to the conservation of the listed mussels (see responses to comments 2 and 5). We do not believe that the Brushy Creek feeders or other similar sites not included in this designation provide ``nursery'' areas for mussels that are necessary for their recovery. The concept of a nursery area implies that mussels occupy one area as juveniles and another as adults. We have no evidence that such movements are occurring. Public Comments (10) Comment: Line Creek in Unit 5 (Upper Flint River) does not provide suitable habitat for the listed mussels. [[Page 64289]] Our Response: Live listed species have been found in Line Creek downstream of its confluence with Whitewater Creek since 1990, and this segment contains PCEs. Consistent with our criteria for identifying critical habitat, we included this section of Line Creek in Unit 5. (11) Comment: Critical habitat designation will add costly delays to permitting a recreational reservoir on Tired Creek, which is upstream of designated habitat in Unit 9 (Upper Ochlockonee River). Our Response: The Service is designating critical habitat only where the mussels are currently present. Therefore, a Federal action that ``may affect'' critical habitat (and would trigger formal interagency consultation) would also result in a ``may affect'' determination for one or more mussel species (requiring formal consultation in and of itself). Our regulations prescribe specific timeframes in which to complete the formal consultation process with Federal agencies. These timeframes are the same whether or not critical habitat is designated and consulted upon during the required consultation process. Critical habitat designation does not create a separate consultation process. While the need to consult on adverse modification on critical habitat does not increase the statutorily allowed amount of time for consultation, it could increase the amount of effort that goes into the consultation process due to the different criteria for a jeopardy consultation versus an adverse modification consultation. Consideration of designated critical habitat in other environmental requirements (such as National Environmental Policy Act (42 U.S.C. 4321 et seq.)), similarly would not add to the length of time needed to comply with those requirements. (12) Comment: The proposed critical habitat for the seven mussels overlooks large areas of potential habitat and essentially disregards the Service's own recovery goals for these species. The Service should designate unoccupied areas containing PCEs within the historical range of the seven mussels. Our Response: Our June 6, 2006, proposed rule explained how we delineated the upstream and downstream limits of proposed critical habitat using the collective current distribution (post-1990 surveys) of all seven mussels and landscape features (e.g., tributary confluence, upstream extent of a reservoir) that indicated a significant change in aquatic habitat conditions (71 FR 32757-32758 ``Criteria Used To Identify Critical Habitat''). This approach resulted in 11 hydrologically and ecologically contiguous units, each of which is a collection of stream segments that flow unimpeded by fish passage barriers into a common reservoir or estuary. Moreover, as we noted in our response to peer-review comment 2, the total stream length delineated by these methods meets the geographic range recovery criteria in the recovery plan (Service 2003) for each of the five species listed as endangered. (13) Comment: Currently occupied habitat is insufficient for conservation of the seven mussels and, therefore, the critical habitat designation must include unoccupied habitat. Unsurveyed tributary creeks that likely support the seven mussels are excluded from the proposed critical habitat because the Service cannot confirm that mussels are present. Our Response: Our recovery plan for the seven mussels (Service 2003) notes that re-introduction in presently unoccupied habitat is needed for the conservation of the five mussels listed as endangered, but not for the two threatened, species. The two threatened species, the Chipola slabshell and the purple bankclimber, each occupy well more than 50 percent of the historical range, which is the criterion we adopted for range expansion as a measure of recovery in the recovery plan. For the five endangered species, the stream length included in the designation meets the recovery plan's geographic range recovery criteria (see our responses to peer-review comment 2). Therefore, we believe the units designated provide a sufficient amount of habitat to support recovery, which precludes the need to designate unsurveyed tributaries that are not known to support the seven mussels. Nevertheless, we would recognize the contribution towards recovery of any populations found in previously unsurveyed streams in our periodic reviews of the conservation status of the seven species. (14) Comment: While permanently flowing water is essential to the seven mussels' survival, flowing water alone is insufficient for the conservation of these species. The final rule should adopt the Service- Environmental Protection Agency (EPA) instream flow guidelines as the flow-related PCE. Our Response: We discussed in the June 6, 2006, proposed rule the role of natural variability in the flow regime to the structure, composition, and functioning of riverine biological communities. The Service-EPA flow guidelines are measures of flow variability that may serve as thresholds for ``may affect'' determinations for proposed Federal actions that would alter a flow regime (e.g., water withdrawals, dam operations). It was not practical or useful to compute the flow guidelines for the entire region that this designation spans, because the guidelines were designed as a tool for site- and project- specific analysis. Further, the guidelines do not establish a general standard or ``bottom line'' for flow regime features that are essential to the conservation of listed species. Recognizing the many complexities involved in quantifying essential flow regime features for the seven mussels, we adopted a qualitative expression that applies throughout the range of the seven mussels and is clearly necessary for their recovery: ``permanently flowing water.'' (15) Comment: Riparian buffers are essential to the conservation of the seven mussels and should be designated as primary constituent elements. If the final rule does not include intact riparian buffers as a primary constituent element, it should address riparian zones as a necessary element of related primary constituent elements. Our Response: Many factors operating outside the channel in the larger watershed affect streams and their inhabitants. Conditions in the riparian zone are among the most influential of these factors by virtue of immediate proximity to the stream channel, but the seven mussels do not occur in the riparian zone. A wide array of riparian buffer dimensions and vegetative characteristics are associated with the mussels. Activities within the riparian zone are among those that may adversely affect the PCEs, and likewise, some conservation actions to protect or enhance the PCEs may occur within the riparian zone. However, specific biological and physical features within the riparian zone are themselves not essential to the conservation of the seven mussels. We have used the ordinary high water marks of the channel as the lateral bounds for this designation (see also our response to comment 7), which encompasses all of the PCEs that we have defined for this designation. (16) Comment: One PCE recognizes fish hosts as necessary to ``support the larval life stages of the seven mussels,'' but none address the habitat needs of the host fish species. The final critical habitat designation should be consistent with the rule for five Tennessee and Cumberland River mussels, which defined ``Fish hosts with adequate living, foraging, and spawning areas for them'' as a PCE, and also linked the ``flow regime'' and ``water quality'' PCEs [[Page 64290]] for the mussels with the needs of the host fish. Our Response: PCEs are essential physical and biological features that are found within critical habitat, the lateral boundaries of which we have delimited as the ordinary high water marks of the stream channel. The final critical habitat rule for five endangered mussels in the Tennessee and Cumberland River basins also used the same criteria (ordinary high water mark) to define the lateral boundaries of critical habitat. Therefore, while the wording of the PCEs might be different, the protection levels are the same since both use the ordinary high water mark to delineate the lateral boundaries of critical habitat. Several fish species that have been identified through laboratory tests as potential hosts for the seven mussels are known to spawn most successfully in floodplain habitats (e.g., largemouth bass), which occur outside the critical habitat boundaries. We agree that the habitat needs of host fish are important considerations in mussel conservation, but as with our response to Comment 15 regarding riparian buffers, we distinguish between PCEs and factors that may affect PCEs. The timely presence of appropriate host fish is the habitat feature that is essential for the survival and recovery of the mussels (i.e., the PCE itself), whereas the habitat requirements of the host fish are factors affecting that PCE. (17) Comment: The rule does not contain the summary of data on which the proposal is based, does not show the relationship of such data to the rule proposed, or provide citations to the mussel surveys relied upon, as required by the Service's regulations at 50 CFR 424.16. Our Response: Our summary of data supporting the PCEs is provided in the ``Primary Constituent Elements'' section. Our summary of data supporting the delineation of units is given in the ``Criteria Used To Identify Critical Habitat'' section. The mapping process involved an overlay of all available site-specific locality data for the seven mussels, which itself was not included in the published proposed rule and is not included in this final rule. The sources for all mussels survey data used in the mapping process are cited at the conclusion of each unit's description, where we list the species for which each unit is designated. A complete list of these and all references cited in this rulemaking is available upon request from the Panama City Ecological Services Office (see ADDRESSES). (18) Comment: The Service should not designate Swift Slough, which is part of Unit 8 (Apalachicola River), because it does not have the permanently flowing water PCE. Our Response: It is not necessary for all PCEs to be present in all portions of critical habitat at all times (see our response to Comment 8). Habitat features change over time, and different portions of a unit will provide a different mix of the PCEs. At the time we initially drafted the proposed rule, we were not yet aware of sediment accumulation in Swift Slough that now results in its disconnection from the main channel of the Apalachicola River during low flows. Although mussels in Swift Slough have suffered considerable mortality since the summer of 2006, some animals persist from what was apparently a relatively large population. Swift Slough still meets the criteria we used to identify critical habitat; therefore, it is still included in the designation. (19) Comment: Water withdrawals are mentioned as causing changes in riverine habitats. This is a mis-statement of facts. If water is withdrawn and used and properly treated and returned to the basin of origin, it does not change the riverine habitat. Our Response: Most out-of-stream uses of water return less than 100 percent of the water that is withdrawn, due to evaporation and other losses. In 2005, about half of the water withdrawn for municipal and industrial use in the Chattahoochee Basin upstream of West Point Dam was not returned to the river (Georgia Environmental Protection Division, unpublished data). Water withdrawals may affect aquatic habitat conditions and aquatic communities, depending on their timing and magnitude relative to stream flow. For example, fish assemblages were significantly less diverse downstream from relatively large water withdrawals and downstream from water supply reservoirs in the lower Piedmont region of Georgia (Freeman 2005). (20) Comment: The fact that the fecal coliform bacteria standard is violated in some reaches of the critical habitat has no effect on mussels. This standard is set to protect humans engaging in whole body contact with the water such as swimming. Our Response: We agree that fecal coliform bacteria standards are established to protect human health and violations of these standards do not necessarily indicate conditions that are harmful to mussels. However, it is possible that some of the bacteria and protozoans associated with wastewater discharges, which often includes fecal coliform bacteria, may adversely affect mussel reproduction (Goudreau et al. 1993:221). High fecal coliform levels may also derive from non- point sources such as pastures and farms following rain events. Because the overland runoff that delivers fecal coliform bacteria from non- point sources to streams may also carry pesticides, fertilizers, and other pollutants, elevated levels of other pollutants are often associated with high coliform counts. (21) Comment: The statements that ``Many pollutants in the ACF Basin originate from * * * and municipal waste water facilities'' in the proposed rule implies that waste water facilities are the source of pollutants that are harmful to the mussels. This is not correct if the waste water facilities are in compliance with National Pollutant Discharge Elimination System (NPDES) permits. All NPDES permits are required to ``not violate water quality standards,'' therefore the mussels would be protected. The fact that someone counted 137 municipal waste water facilities in the ACF basin is not relevant to the protection of the mussels assuming that these facilities all have NPDES permits and are in compliance. To arbitrarily assume that these facilities are not in compliance without factual data is wrong and is unscientific. Our Response: Municipal waste water treatment processes remove most but generally not 100 percent of all pollutants. Although treatment facilities and other point-source discharges may comply with NPDES permit conditions, the combined pollutant loading from all sources in a watershed may contribute to a total loading such that some reaches do not meet one or more water quality standards. When a stream is identified as impaired under the Clean Water Act (33 U.S.C. 1251 et seq.), the States initiate a process for developing total maximum daily load regulations under their delegated administration of the Clean Water Act. Our proposed rule indicated which critical habitat units contain stream segments on the impaired waters lists of the States. Our reference to the number of treatment facilities in the ACF Basin was part of describing the environmental setting of the critical habitat units. We did not assume or mean to imply that treatment facilities in the ACF were or were not in compliance with NPDES permits. (22) Comment: These two statements in the proposed rule contradict each other: (1) ``The ranges of several standard physical and chemical water quality parameters (such as temperature, DO, pH, conductivity) that define suitable habitat conditions for the seven mussels have not been specifically investigated;'' and (2) ``Various contaminants in point and non-point [[Page 64291]] source discharges can degrade water and substrate quality and adversely affect mussel populations.'' Our Response: Our reference to ``several standard physical and chemical water quality parameters'' did not include contaminant concentrations. Parameters are those that aquatic biologists routinely measure with instruments in the field. Concentrations of contaminants that are known to adversely affect mussels, such as ammonia and heavy metals, are generally measured using water or sediment samples taken to a laboratory and not using instruments in the field. We have revised the rule language to avoid the apparent contradiction of these two statements. (23) Comment: There is no scientific basis given for implying that septic systems are responsible for mussel threats. Our Response: We include maintaining septic systems among the management considerations to deal with the threat of pollution to mussel habitats because inadequately maintained systems may contribute nutrients and other pollutants to ground water that can seep into surface water bodies. Nutrient loading can lead to algal blooms and low dissolved oxygen levels that adversely affect mussels, which we discuss under the water quality PCE. (24) Comment: The impacts associated with Whitewater Creek Park are minimal; therefore, the Service should exclude Macon County, Georgia, from the designation. Our Response: We do not include Whitewater Creek and Whitewater Creek Park in Macon County in designated critical habitat for the seven mussels. However, we do include a different Whitewater Creek in Fayette County, Georgia. We also include the main channel of the Flint River and Hogcrawl Creek in Macon County as parts of Unit 5 (Upper Flint River). (25) Comment: Critical habitat for the seven mussels is not determinable because the Service has insufficient data. Most of the mussel distributional records are from the early 1990s and further studies are needed to define suitable habitat conditions for the seven mussels. Our Response: Much of the survey data upon which we relied dates from the early 1990s, but this does not in and of itself render critical habitat undeterminable. The Act contemplates critical habitat designation ``at the time it [the species] is listed'' (Sect. 3(5)(A)(i)); therefore, we must necessarily rely on distributional data from the time of listing as well as more recent data. It happens that most of our records are from the early 1990s because the most comprehensive survey effort in the range of the seven mussels immediately preceded the listing proposal, which was published on August 3, 1994 (59 FR 39524). Due to a moratorium on listing actions declared by Congress shortly thereafter, we did not publish a final rule until March 16, 1998 (63 FR 12664). We agree that further studies are needed to more quantitatively define the seven mussels habitat requirements; however, the best available information regarding those requirements is sufficient to define qualitative but workable and meaningful PCEs. Further, the PCEs adopted in this rule are generally consistent with those adopted in previous rules designating critical habitat for freshwater mussels. (26) Comment: Contrary to the Service's regulations at 50 CFR 424.12(c), the Service has used an imprecise ephemeral boundary, the ordinary high water marks, to define the lateral extent of the proposed critical habitat area. Our Response: Although the ordinary high water marks of a stream may shift location over time, they do not disappear. The intent of the regulation cited is avoiding reliance in critical habitat descriptions on ephemeral features, i.e., features that last a relatively short time. We agree that the ordinary high water marks are not a precise or a fixed set of coordinates over time, but they are an appropriate descriptor for dynamic riverine habitat. A fixed set of coordinates that would fully encompass the areas we have determined are essential would either become quickly obsolete through natural or human-induced lateral channel migration, or would delineate an overly broad area by including a fair amount of terrestrial habitat. (27) Comment: The analysis of what activities may affect the proposed critical habitat designation set forth in the proposed rule is both misleading and incomplete. As a result some persons may conclude by default that any and all activities affecting portions of the critical habitat, however minimally, will require consultation under section 7 of the Act. Our Response: The section 7 consultation process applies only to Federal actions. Federal agencies are responsible for determining whether their actions may affect listed species or designated critical habitats. Action for which the action agency makes ``no effect'' determinations does not require further consultation with the Service. Service concurrence is required for other determinations, and the Service routinely assists Federal agencies in defining classes of actions that may comply with section 7 through informal consultation. The formal consultation process, which requires the Service to prepare a biological opinion, applies to those actions that Federal agencies determine may adversely affect the listed species or designated habitat. We do not expect the designation of critical habitat to appreciably increase either the number of actions per year to which the consultation process applies or for which formal consultation is required. (28) Comment: The proposed rule provides no guidance for determining which features of the flow regime are important to mussels and their host fishes. Therefore, it is impossible to determine whether the Service has actually made a determination that certain activities presumptively ``may affect'' critical habitat. The Service-United States Environmental Protection Agency instream flow guidelines referenced in the proposed rule do not provide a sufficient or appropriate basis for evaluating proposed activities, because the guidelines are not self-explanatory and are not obviously relevant to the seven mussels. Our Response: The measures of flow magnitude, duration, frequency, and seasonality that are included in the Service-USEPA instream flow guidelines (USFWS and USEPA 1999) may be used to determine whether Federal actions may affect listed species. This is the express purpose of the guidelines, which is relevant to the seven mussels. Application of the guidelines for this purpose is a site-specific and data- intensive process that involves computing long-term flow statistics for a project area with and without a proposed Federal action. Actions that would alter the flow parameters included in the guidelines, e.g., increase the maximum number of days per year that flow is less than 25 percent of average annual discharge, may adversely affect listed species and require formal consultation. The process for computing and applying the guidelines is explained in the guidelines document. However, to provide more information about the guidelines in this designation, we have added a listing of the flow regime features that are included in the guidelines to the flow regime PCE discussion. (29) Comment: The Service should follow the procedures prescribed by the National Environmental Policy Act (NEPA) as part of this rulemaking. Our Response: It is our position that, outside the jurisdiction of the Tenth Federal Judicial Circuit, we are not required to prepare environmental analyses as defined by NEPA in [[Page 64292]] connection with designating critical habitat under the Endangered Species Act of 1973, as amended (see Required Determinations--NEPA). (30) Comment: The Service fails to note that impoundments are very efficient in removing sediment, with large southeastern reservoirs trapping 80-90% of the incoming sediment. Our Response: In the ``Summary of Threats to Surviving Populations'' section, we note how impoundments block the natural downstream movement of sediment, which commonly leads to channel degradation in the tailwaters of dams built in alluvial rivers (Williams and Wolman 1984, p. 14; Lignon et al. 1995, p. 187). Rather than providing a net benefit to mussels by trapping excessive sediment loads, dams may largely remove native riverine mussels from tailwater areas through channel scouring processes as well as from stream segments inundated by reservoirs. For example, the fat threeridge was formerly abundant but is now rare in the upstream reaches of the Apalachicola River, most likely due to substantial channel incision resulting from the construction of Jim Woodruff Lock and Dam. (31) Comment: The Service fails to note that impoundments with large storage capacity may increase base flows downstream during periods of drought. Increased minimum flow may benefit downstream mussel habitat. The storage capacity of large reservoirs may also reduce the impact of flood flows that historically would result in scour and bank erosion. Our Response: The seven mussels evolved under natural flow regimes that include droughts and floods. Human consumptive uses of water may decrease stream flow below naturally occurring levels, and releases from reservoirs may offset the impact of this depletion, depending on how reservoirs are operated. However, reservoirs generally reduce the average annual discharge of a river by increasing evaporative losses via a greater water surface area. Increasing river flow with releases from reservoir storage necessarily requires decreasing river flow at other times to replenish storage, which may adversely affect mussels. However, we are aware of no evidence that the magnitude, frequency, duration, or timing of flood flows has been appreciably altered by dams in the stream reaches that are included in this critical habitat designation. (32) Comment: Relative to the application of the jeopardy and adverse modification standards, the Service provides no evidence that the operation of dams would alter flows in a manner that would destroy or adversely modify critical habitat. Our Response: Federal actions that would destroy or adversely modify critical habitat are those that alter the PCEs to an extent that the conservation value of the habitat is appreciably reduced. We included dam operations as an activity that could, but does not necessarily, significantly alter flow regimes. Determining whether dam operations may adversely affect critical habitat is a site- and project-specific analysis. The Service-USEPA instream flow guidelines (USFWS and USEPA 1999) are an appropriate tool for making such determinations (see comment 28). It is not necessary to establish that an action, such as dam operations, is certain to adversely modify critical habitat in order to name it in our designation among the actions that could do so. (33) Comment: The Service is required to list the specific PCEs for each individual mussel in each unit designated as critical habitat. The Service does not provide evidence, explanations, or citations detailing the requirements of each species relative to each of the PCEs. Our Response: The Act and our regulations do not prohibit multi- species critical habitat designation rules, and the Service has previously issued several multi-species critical habitat rules in which a common set of PCEs applies to more than one species (for example, July 17, 2007, final rule for Peck's Cave amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle, 72 FR 39248). We acknowledge that each of the seven mussels has a unique life history and niche in the riverine environment, but that these are similar enough to describe PCEs for the seven mussels as a group. Although the PCEs are the same for all seven mussels, the mix of units designated as critical habitat for each species is unique, reflecting differences in their spatial distribution. (34) Comment: The rule should address the threat of dam removal to the mussels and include dam removal as an action that could appreciably alter the channel stability and flow PCEs. Our Response: The Service is unaware of dam removal proposals within the areas we are designating as critical habitat. Dam removal could conceivably initiate channel instability; however, the most likely motivation for a dam removal project would be restoration of free-flowing conditions that were previously impaired by impoundment. This is the motivation for the proposed removal of the Eagle-Phenix Dam and the City Mills Dam, which would restore a total of approximately 2.3 miles of the biologically significant Fall Line shoal habitat in the Chattahoochee River. Although this area has not been designated as critical habitat, it is within the historical range of some of the seven mussels. Eagle-Phenix and City Mills dams do not store an appreciable volume of water, and removing these dams would not affect downstream flow regimes. (35) Comment: The proposed rule cites no evidence to support the assertion that the seven mussels are not found in impoundments. Our Response: Brim Box and Williams (2000) surveyed 324 sites in the ACF, including several sites within several impoundments, including Lake Seminole, Lake Walter F. George, and West Point Lake. They found no live individuals of the listed species within any of the impoundments. Economic Analysis--Policy Issues (36) Comment: Multiple commenters requested the economic analysis consider those impacts due solely to the designation of critical habitat for the seven mussels. Our Response: Appendix B of the Final Economic Analysis (FEA) estimates the potential incremental impacts of critical habitat designation for the seven mussels. It does so by attempting to isolate those direct and indirect impacts that are expected to be triggered specifically by the critical habitat designation. The incremental conservation efforts and associated impacts included in Appendix B would not be expected to occur absent the designation of critical habitat for the seven mussels. Total present value potential incremental impacts are estimated to be $501,000. All other impacts quantified in the FEA are considered baseline impacts and are not expected to be affected by the critical habitat designation. (37) Comment: Several commenters stated the Initial Regulatory Flexibility Analysis does not adequately estimate the potential impacts to small entities. Our Response: Appendix C in the FEA has been revised and now considers the extent to which the incremental impacts analysis described in Appendix B could be borne by small entities and the energy industry as opposed to fully co-extensive impacts quantified in Sections 3 though 6. The incremental impacts of the rulemaking are considered most relevant for the small business and energy impacts analyses as they are expected to stem from the critical habitat designation, and are therefore not expected to occur in the case that critical habitat is not [[Page 64293]] designated for the seven mussels. The analysis concludes that one hydropower operator and 10 deadhead logging companies may be affected by critical habitat designation as proposed. (38) Comment: One commenter states that the Draft Economic Analysis (DEA) explains that no estimates of minimum flow have been developed by the Service or any other entity. In order to assess ultimate hydropower impacts, these estimates must be made, and included in the economic analysis. Our Response: In the absence of information on minimum flow levels for the seven mussels the FEA relies on the best available information solicited from resource managers on the likely efforts that would be needed to protect the seven mussels to estimate the potential future impacts associated with conservation efforts in areas proposed for designation. (39) Comment: One commenter indicates that the impacts of implementing the U.S. Army Corps of Engineers (USACE) Modified Interim Operating Plan (Modified IOP) need to be distributed between gulf sturgeon and mussels, as it considers both. Our Response: The Modified IOP is intended to protect the mussels, their host fish, and gulf sturgeon. Specific information on which species generated which conservation efforts in the plan is not available. This analysis therefore quantifies the full impact of the plan as co-extensive with seven mussels conservation. Appendix B in the Final Economic Analysis (FEA) estimates the incremental impacts associated solely with the designation of critical habitat for the seven mussels; impacts associated with the Modified IOP are not considered to be incrementally due to critical habitat. (40) Comment: Several commenters state that potential benefits of critical habitat designation should be quantified. Our Response: The economic analysis conducted for this rule points out that there are some potential benefits of critical habitat designation. However, it is difficult to develop credible estimates of such values, as they are not readily observed through typical market transactions and can only be inferred through advanced, tailor-made studies that are time consuming and expensive to conduct. We currently lack both the budget and time needed to conduct such research before meeting our court-ordered final rule deadline. The economic analysis is done primarily to provide decisionmakers with information about potential exclusions from the rule. Given the impracticality of conducting this additional analysis we do not believe it is necessary to quantify the positive consequences of this rule in order to weigh the benefits of including versus excluding areas from the rule. The Congress has already determined that the benefits of species recovery are high. Therefore, we do not require quantification of how high in order to make a sound decision. Economic Analysis--Economic Issues (41) Comment: One commenter states that the DEA did not desegregate impacts in Unit 8, Apalachicola River to focus on Swift Slough, River Styx, and Kennedy Slough. Our Response: The water management adopted per Reasonable and Prudent Measure (RPM) 3 of the Biological Opinion for USACE operations at Jim Woodruff Dam raised the minimum flow in the Apalachicola River to 6,500 cfs when composite storage (all reservoirs combined) is above zone 3, at which time it reverts to 5,000 cfs. At this time the Service does not anticipate maintaining higher minimum flows for Swift Slough, River Styx, and Kennedy Slough than already considered in the Modified IOP. Therefore, the FEA does not estimate any additional impacts associated with these tributaries. (42) Comment: One stakeholder commented that the Modified IOP is an interim plan and can change soon. Another commenter noted that the USACE 2007 Environmental Assessment quoted in Section 4 of the report has not been vetted through an official process, and that a May 16, 2007, letter from USACE to the Service indicates that changes to Modified IOP operations are ongoing, and make USACE statements suspect as they are subject to change. Our Response: The USACE currently manages its operations in accordance with the 1989 Draft Water Control Plan for the Apalachicola- Chattahoochee-Flint (ACF) reservoir system and makes minor adjustments as necessary to accommodate changes in current needs. Current management under the Draft Water Control Plan is set out in the Modified IOP. The Modified IOP reflects how the USACE is regulating the minimum releases and maximum fall rates at Jim Woodruff Dam. In 2007, the USACE completed an Environmental Assessment of the Modified IOP. Finalization of the Draft Water Control Plan depends on the result of ongoing litigation filed by the State of Alabama in 1990. Although it is expected that the Water Control Plan, and the Modified IOP will be updated subsequent to the resolution of the litigation process, information is not available to identify what changes to management may occur. The FEA therefore applies the best information available, i.e., the Modified IOP and Draft Water Control Plan, regarding water management and acknowledges the uncertainty regarding this activity in the future. (43) Comment: A few commenters stated that the input parameters that the USACE uses for its HEC-5 hydrological model differ from the parameters used by Georgia and Florida and that the results presented in the DEA could change if these different input parameters are included in the analysis. Our Response: To address the comment, the FEA includes additional results from Georgia Environmental and Protection Division's (EPD) analysis of the Modified IOP. Section 2 has been updated with a detailed discussion of how the USACE's assessment of the depletion of water storage in the major dams on the Chattahoochee River is consistently less than Georgia EPD's assessment. Several exhibits have been added that compare the two agencies' interpretations of the impact of the Modified IOP on reservoir storage capacity. The comparisons are made for both year 2000 and year 2030 water demand levels, and for normal and drought conditions. Section 3 of the FEA was revised to include these new estimates. Using this new information the present value of potential economic impacts to recreationists associated with conservation efforts for the seven mussels in Unit 8, Apalachicola River, increased to be between $27.7 million and $54.1 million (discounted at three percent). (44) Comment: A commenter stated that the Service's use of instream flow guidelines in Section 2 of the DEA was not mentioned in the September 2006 Biological Opinion on USACE's IOP for Jim Woodruff Dam. Our Response: Instream flow guidelines discussed in the DEA are as described by the Service in the June 6, 2006, proposed rule for the critical habitat designation of the seven mussels, not the 2006 biological opinion. The EPA-USFWS guidelines are referenced in Section 2 of the FEA. (45) Comment: One commenter stated that the assumption that municipal and industrial impacts may result due to USACE's water management operations of the ACF system is directly contradicted by USACE language, which indicates that lake levels will not fall below water intake structures because of operations under the Modified IOP. Our Response: The USACE analysis of the impacts of the Modified IOP impacts models year 2000 water demand; it does not assess the impact of the Modified IOP for year 2030 water demands. [[Page 64294]] However, Georgia EPD provides simulated lake levels for both year 2000 and year 2030 water demand levels. Section 2 of the FEA, discusses how model simulations conducted by the Georgia EPD suggest that lake levels may go below water intake structures in the future, especially under year 2030 water demand levels. This can happen even without the modifications introduced by the Modified IOP. Thus, in the case that sustained drought conditions exist in the future, the Modified IOP can potentially further decrease lake levels. Potential Economic Impacts Related to Changes in Water Use and Management (46) Comment: A few commenters have expressed reservations about attributing the impact of the Modified IOP on municipal and industrial water supply and recreation to the critical habitat of the three mussels found in the Apalachicola River complex because the Modified IOP predates the designation. Our Response: The impact of the Modified IOP on municipal and industrial water supply is not quantified in the DEA. For recreation related impacts, which are quantified in Section 3, the FEA quantifies the fully co-extensive impacts of any Federal, State, or local regulations or guidelines that may benefit the seven mussels in the proposed critical habitat area. Appendix B of the FEA acknowledges that implementing the Modified IOP is not an incremental impact attributable to the proposed rule. (47) Comment: Several commenters have indicated that water quality could become a concern at lower lake levels. Our Response: Section 2 of the FEA notes these concerns based on Georgia EPD's analysis of how declining lake levels during sustained periods of drought could expose the water intake structures of several local governments in Georgia. Additionally, Georgia EPD concludes that the Modified IOP leads to an increase in the number of days that the desired flow for wastewater assimilation below the Columbus gage will not be met. Section 5 discusses other potential water quality-related impacts. These potential water quality impacts are associated with Modified IOP implementation and are not expected to result from the critical habitat designation as proposed. (48) Comment: One commenter mentioned that there is no mechanism for the Flint River Drought Prevention Act (FRDPA) to restrict agricultural uses based solely on impacts to protected mussels. Our Response: The DEA does not make assumptions or recommendations regarding how changes in irrigated agricultural use will occur, or who will bear the cost of changes in water management and use. As discussed in Section 6 of the FEA, the Georgia Department of Natural Resources, Wildlife Resources Division plans to develop a Habitat Conservation Plan (HCP) to address agriculture related impacts to seven mussels conservation in the Lower Flint River Basin. The HCP is expected to reduce irrigation in the Lower Flint River Basin during severe drought. In addition, there were reverse auctions conducted associated with the Flint River Drought Protection Act (2000), during which irrigation rights were purchased from farmers, during the drought periods in 2001 and 2002. (49) Comment: Several commenters indicate that information necessary to quantify municipal and industrial impacts is ``readily available and should have been collected and analyzed as part of the economic analysis.'' Our Response: Section 3 of the FEA explains that it was unable to estimate the impacts of mussel conservation efforts on municipal and industrial water supply because of numerous uncertainties in the relationship between water management under the Modified IOP and water supply. To quantify these impacts, the following information is needed: (a) The relationship between lower lake levels due to the Modified IOP and the risk that municipal water use will be restricted in some way (i.e., the marginal increase in risk of droughts being declared); (b) the amount of water lost from each sector (e.g., industry) within Chattahoochee River Basin municipalities due to drought restrictions and quantification of the effect of timing restrictions on water availability; and (c) data to estimate the value of less transparent water uses (e.g., lawn watering). These data are currently not available. (50) Comment: One commenter indicated that the DEA underestimates the economic impacts associated with critical habitat designation at West Point Lake, citing preliminary results from an ongoing study. The FEA indicates that impacts associated with low water levels (i.e., water levels below top pool elevations) not specifically due to the Modified IOP may be as high as $90 million. The commenter states the following: (a) Recreation visits are underestimated, (b) the DEA did not consider estimates of rapid growth associated with the greater LaGrange, Georgia area, (c) property value changes in response to changes in lake level are not analyzed, and (d) the estimate of average boating expenditures within 30 miles ($68 per trip) is low. Our Response: The West Point Lake study described by this commenter was commissioned to investigate the economic impact of low water levels, which are only in part influenced by the mussel conservation efforts. In response to the specific points: (a, b) A new source of data on visitation to West Point Lake has been identified and incorporated into the FEA (increasing the present value estimate of potential future impacts to recreationists at West Point Lake to between $11.0 million and $16.5 million, discounted at three percent). (c) Estimating property value impacts would require a study that has: (i) Estimated how property values in the region (ideally, at West Point Lake) have changed in response to changing lake levels and (ii) is capable of characterizing the marginal change in property values of changes in lake levels. Such a study has not been identified. (d) Average boating expenditures are used in the regional impact analysis. The within 30-mile expenditure value of $68 per trip is the best estimate currently available. The $95 estimate includes nationwide travel expenditures to Lake Lanier and therefore cannot be used to estimate regional impacts