Potential for Impacts to Endangered Karst Invertebrates from the Proposed 183 North Mobility Project, Travis and Williamson Counties, Texas

TECHNICAL REPORT

Prepared for CP&Y, Inc.

Prepared by Cambrian Environmental

with

SWCA Environmental Consultants

SWCA Project No. 25572

September 9, 2015 This page left intentionally blank TECHNICAL REPORT OF THE POTENTIAL FOR IMPACTS TO ENDANGERED KARST INVERTEBRATES FROM THE PROPOSED 183 NORTH MOBILITY PROJECT, TRAVIS AND WILLIAMSON COUNTIES, TEXAS

Prepared for

CP&Y, Inc. The Chase Bank Building Tower of the Hills 13809 Research Blvd, No. 300 Austin, Texas 78750 Attn: Andy Atlas

Prepared by

CAMBRIAN ENVIRONMENTAL 4422 Pack Saddle Pass No. 204 Austin, Texas 78745

with

SWCA ENVIRONMENTAL CONSULTANTS 4407 Monterey Oaks Blvd No. 110 Austin, Texas 78749

September 9, 2015

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TABLE OF CONTENTS

Introduction ...... 1 Ecological Significance of Karst Invertebrates ...... 3 Origin of Karst Invertebrate Habitat in the Project Area ...... 7 Environmental Baseline ...... 8 Potential for Endangered Karst Invertebrates to Occur In the Project Area ...... 14 Potential Endangered Karst Invertebrates in the Project Area ...... 19 Bee Creek Cave Harvestman ( Texella reddelli ) ...... 19 Bone Cave Harvestman ( Texella reyesi ) ...... 19 Tooth Cave Ground Beetle ( Rhadine persephone ) ...... 19 Tooth Cave Spider ( Tayshaneta “Neoleptoneta” myopica ) ...... 20 Potential for adverse affect on Endangered Karst Invertebrates ...... 22 Direct and Indirect Effects ...... 23 Interrelated and Interdependent Effects ...... 24 Incidental Take...... Error! Bookmark not defined. Conclusions ...... 24 References ...... 26

FIGURES

Figure 1. Project location ...... 2 Figure 2. Geologic map of the Project Area...... 9 Figure 3. Generalized Stratigraphy of the Project Area...... 10 Figure 4. USFWS Karst Zones of the Project Area...... 11 Figure 5. Karst Fauna Regions (KFRs) of the Project Area...... 12 Figure 6. Known Endangered Karst Invertebrate Caves Near the Northern End of the Proposed Project Area...... 16 Figure 7. Location Map of Fossil Cave Relative to Project Area...... 17 Figure 8. Location Map of Marquis Sink Relative to Project Area...... 18 Figure 9. Habitat Map Showing Known Distribution of Listed Karst Species Near Project Area (USFWS 1994a, 2009a,b)...... 21

PHOTOGRAPHS

Photograph 1. The vestigial eye of this central Texas Rhadine sp. beetle is an example of regressive troglomorphic traits exhibited by cave-adapted fauna...... 4 Photograph 2. Surface-adapted (left) and cave-adapted (right) spiders of the genus Cicurina show dramatic differences in eye development. Whereas the surface species Cicurina varians (left) has the normal 8-eyed configuration, the cave-adapted species C. vibora (right) lacks even the vestigial eyes exhibited by many troglobites...... 5 Photograph 3. The endangered Bone Cave harvestman (Texella reyesi ) exhibits elongated appendages and eyes that are reduced in number and size. Specimen pictured is partially dissected (legs removed for clear view of cephalothorax profile)...... 6 Photograph 4. The millipedes of the genus Speodesmus lack eyes and pigment and exhibit elongated legs...... 6 Photograph 5. Interstitial void formed within the Edwards Limestone. A coating of mineral deposits has biologically isolated the void from other voids in the karst network which may be biologically active...... 8

TABLES

Table 1. Karst invertebrate habitat protected under the Williamson County Regional Habitat Conservation Plan to date...... 13

ATTACHMENTS

Attachment A. Expected Bedrock Removal Quantities Within Project Area

Attachment B. Location Maps For Expected Bedrock Removal Within Project Area

INTRODUCTION

The proposed 183 North Mobility Project (Project) is a cooperative effort by the Central Texas Regional Mobility Authority (CTRMA) and the Texas Department of Transportation (TxDOT) to improve US 183 from State Highway (SH) 45/Ranch-to-Market Road (RM) 620 to Loop 1 (MoPac) (CSJ 0151-05-100 and 3136-01-185).Proposed Project activities involve a total of approximately 724.6 acres; 714.2 acres of existing right-of-way (ROW), 8.0 acres of proposed ROW, and 2.4 acres of existing easements, as shown in Figure 1 (Project Area). Construction activities are expected to include the reconfiguration of existing road surfaces and the addition of new lanes. This work will involve reconfiguration of some existing structures; surface grading (generally to a depth of three to four feet below existing grade); excavation for piers to support bridges, overpasses, or flyovers (generally to depths of between 10 and 45 feet); construction of new road surfaces and ancillary structures; the expansion or improvement of existing water quality controls; and the addition of new water quality controls, as needed. Attachment B contains a detailed estimate of bedrock excavation within the Project Area and Attachment C contains location maps for expected bedrock excavation.

Seven species of invertebrates known only from caves and voids in Travis and Williamson counties, Texas, are listed by the USFWS as endangered species under the Federal Endangered Species Act of 1973, as amended (ESA). The seven listed species are: the Bee Creek Cave harvestman ( Texella reddelli ), Bone Cave harvestman ( Texella reyesi ), Tooth Cave pseudoscorpion ( Tartarocreagris texana ), Tooth Cave spider ( Neoleptoneta myopica ), Tooth Cave ground beetle ( Rhadine persephone ), Kretschmarr Cave mold beetle ( Texamaurops reddelli ), and Coffin Cave mold beetle ( Batrisodes texanus )1.

1 Chandler and Reddell (2001) described a new species of Batrisodes from Williamson County; Batrisodes cryptotexanus, based on a specimen that was previously thought to be Batrisodes texanus. While the USFWS does not recognize this taxonomic revision, Batrisodes cryptotexanus USFWS considers this species to be synonymous with B. texanus and is therefore listed as endangered and thus protected under the ESA (USFWS 2014c). For the purposes of this report, B. cryptotexanus will be considered synonymous with B. texanus and will not be discussed as a separate entity.

Figure 1. Project location

Even though the Project Area is generally heavily urbanized, unexpected impacts to karst fauna are possible occur due to the cryptic nature of their subterranean habitat. The proposed Project occurs entirely within the Balcones Escarpment in a geographic area (Travis and Williamson counties) known to be occupied by 7 species of endangered karst invertebrates. The purpose of this Technical Report is to assess the potential effects of the proposed Project on listed karst invertebrate species, evaluate if take of endangered taxa is likely to occur, and assess if the proposed Project is likely to jeopardize the continued survival and recovery of listed species.

ECOLOGICAL SIGNIFICANCE OF KARST INVERTEBRATES

Troglobites are obligate cave-dwelling organisms that include more than 1,200 species worldwide (Barr 1968). They are characterized by a number of anatomical and physiologic adaptations to cave life collectively referred to as troglomorphy. Troglomorphic characteristics include loss of pigment and sclerotization (thickness of the exoskeleton in invertebrates), reduction or loss of eyes, elongation of appendages, lengthened life span, modified fecundity, and metabolic adaptation to nutrient-poor habitat conditions. The cave environment is relatively monotonous compared to surface invertebrate habitats and is characterized by stable temperatures close to the mean surface temperature, constant near-saturation humidity, low evaporation rates, and the absence of photosynthetic nutrient production.

Due to the lack of light for photosynthesis, most cave communities lack primary producers. Instead they rely on nutrient input from the surface ecosystem, and as such they are an extension of the surface ecosystem. Nutrients are introduced into the subsurface in the form of plant detritus washed in by floodwater, roots that penetrate the habitat through cracks in the bedrock, organisms that enter the cave under their own power, and the eggs and waste of trogloxene species such as cave crickets. These types of cave communities are essentially decomposer communities (Culver 1982). Other cave ecosystems have been found to derive nutrients from chemoautotrophs that produce energy by breaking chemical bonds in sulfur minerals. However, no evidence of this process playing a significant role in the ecology of Central Texas terrestrial troglobites has been found. As a result of adaptation to this low-energy environment, many troglobites are K-selected (Culver 1982). K-selected species are characterized by delayed reproduction, increased longevity, smaller total egg production, and larger egg size.

The origin and geographic distribution of troglobites have important general implications for researchers of evolutionary biology (Holsinger 1988). Study of cave organisms has long been of interest because of the regressive evolutionary traits associated with troglomorphy that are shared by a wide variety of taxa. Photographs 1–4 illustrate troglomorphic adaptations of central Texas cave fauna. Regressive evolution is especially significant to the field of evolutionary biology because of the possibility that it results from conditions under which the accumulation of neutral mutations (genetic drift) dominates over environmental selection pressures in term of their influence on the composition of the genome (Culver 1982).

Photograph 1. The vestigial eye of this central Texas Rhadine sp. beetle is an example of regressive troglomorphic traits exhibited by cave-adapted fauna.

Many troglobitic species are considered to be relicts persisting in subsurface refugia long after their surface ancestor species abandoned their geographic region due to climate change (Barr 1968). Most terrestrial troglobites are thought to have evolved from a surface ancestor that was pre-adapted for cave life because it belonged to a species adapted to living in cool, moist soil or leaf-litter. Climatic oscillations, such as those during the Pleistocene, periodically brought suitable habitat conditions for these species into and out of geographic areas south of the glacial maxima. During warmer, drier intervals, populations inhabiting caves and sinkholes were able to survive in isolated pockets whereas other populations were forced to migrate to suitable habitat conditions or go extinct. The resulting geographic isolation, reduced population size, and restriction of gene flow combined with troglomorphic selection pressures to produce endemic species. Most of the local endemic karst invertebrates are thought to have arisen through similar processes (Barr 1968, Cokendolpher 2004, Culver 1982, Holsinger 1988, Mitchell and Reddell 1971).

Photograph 2. Surface-adapted (left) and cave-adapted (right) spiders of the genus Cicurina show dramatic differences in eye development. Whereas the surface species Cicurina varians (left) has the normal 8-eyed configuration, the cave-adapted species C. vibora (right) lacks even the vestigial eyes exhibited by many troglobites.

Centers of troglobitic biodiversity in the United States include Texas, the southeast (Appalachian Mountains, Cumberland Plateau, Central Basin of Tennessee, and the Bluegrass and Mammoth Cave regions of Kentucky), and the Sierra Nevada foothills of California. Among all of these areas, Texas ranks second in terrestrial troglobite diversity (Peck 1998). The diversity of troglobitic fauna in Central Texas caves has been attributed in part to its latitude being south of the maximal advance of glacial ice and north of the stable tropical zone. Caves were never covered by ice during Pleistocene glaciations as caves in northern latitudes were and the climatic oscillations associated with climate change continuously brought potential colonizers into and out of contact with caves habitats. The composition of the troglobitic community indicates that glacial periods were more important to producing the overall biodiversity in Texas caves. Eleven genera of troglobites share affinities with northern and northeastern fauna whereas only three genera share affinities with tropical and subtropical fauna (Mitchell and Reddell 1971). Tooth Cave, which has the highest level of biodiversity known in any Texas cave, is located approximately 4.5 miles west of the Project Area.

Photograph 3. The endangered Bone Cave harvestman ( Texella reyesi ) exhibits elongated appendages and eyes that are reduced in number and size. Specimen pictured is partially dissected (legs removed for clear view of cephalothorax profile).

Photograph 4. The millipedes of the genus Speodesmus lack eyes and pigment and exhibit elongated legs.

ORIGIN OF KARST INVERTEBRATE HABITAT IN THE PROJECT AREA

Habitat for cave-adapted fauna in the Balcones Escarpment in Central Texas is the byproduct of the evolution of the Edwards Aquifer, a hydrogeological process acting across approximately 20 million years of evolutionary time. The paleoaquifer developed along the structural grain imparted by the Balcones Fault Zone and the primary porosity of the Edwards Limestone which is the host rock for the great majority of caves in the area. During the Miocene, as the ancestral Gulf of Mexico was subsiding to the southeast, the escarpment was created along a belt of weakness where episodic faulting produced more than 1,000 feet of displacement. The resultant Balcones Escarpment is essentially a fault-line scarp consisting of a series of northeast-trending, predominantly normal, nearly vertical, en echelon (closely-spaced, parallel or subparallel, step-like) faults that are down-thrown toward the coast (Senger et al. 1990).

In the approximately 20 million years since faulting ceased, drainage systems adjusted to this change in topography by accelerating denudation rates along the escarpment. Erosion was particularly focused on fault scarps with the highest displacement. Acting essentially like a giant head-cut, regional drainage systems stripped more than 900 feet of overlying Comanche and Gulf Series strata away from the topographic break, toward the Gulf of Mexico. The top of the Edwards Group Limestones, the dominant cave-forming units in the area, were exposed and had begun to be incised on the San Marcos Platform (a high point in the geological structure) by the middle Miocene on the order of 10 million years ago (Wilson 1956, Ely 1957).

As subsequent portions of the confined aquifer were gradually exhumed by erosion, discrete zones of cavernous porosity became air-filled and were available for progressive colonization by terrestrial fauna (White 2006). Being closest in proximity to karst habitats, it was the edaphobitic (soil dwelling) fauna that first entered the subterranean voids. That the troglobite community is descended from paleo-soil and paleo- leaf-litter fauna is apparent from the fact that both communities share the same basic faunal components (Reddell 1994). Bacteria and actinomycetes were followed by protozoa, nematodes, and rotifers. Mites and springtails formed the base of the scavenger/predator community and, in turn, provided a prey base for insects, myriapods, arachnids, and diplurans. It is this last group of animals who followed convergent evolutionary pathways leading to the remarkable diversity of troglobitic fauna now known from Texas caves. Today the descendants of early cave colonists comprise at least 45 species of obligate terrestrial troglobites in Travis and Williamson counties (Reddell 1993, 1994). They are the living descendants of the surface fauna of the late Miocene sheltered for 10 million years by their subterranean habitat.

The potential for karst invertebrate habitat to occur in the Project Area is directly dependent on the degree of karst development within the underlying bedrock. However, not all voids in the Edwards Limestone are occupied by troglobitic fauna. While troglobitic fauna are known to inhabit mesocavern habitat (small voids connected to the larger caves and sinkholes through which nutrients are able to enter the subsurface), some mesocaverns are interstitial in nature (essentially sealed off from biological activity). Photograph 5 depicts the interior of an interstitial cavern encountered in a sewer line trench in Williamson County. It was sealed off from other voids in the karst network by secondary mineral growth. All surfaces were coated by speleothem deposits and organic material is absent.

Photograph 5. Interstitial void formed within the Edwards Limestone. A coating of mineral deposits has biologically isolated the void from other voids in the karst network which may be biologically active.

The geology of the Project Area consists primarily of a thin veneer of calcareous soil overlying the cavernous Edwards Limestone. Along the MoPac section of the project, non-cavernous Upper Cretaceous rocks of the Washita, Eagle Ford, and Austin groups are exposed (Rodda 1970, Brune and Diffin 1983, Collins 2005, Garner et al. 1976, Housh 2007). The Project Area is located entirely within or adjacent to the recharge zone of the Northern Segment of the Edwards Aquifer (Senger et al. 1990). Portions of the Project Area are within the transition zone of the Northern Segment of the Edwards Aquifer. Figure 2 is a geologic map of the Project Area. Figure 3 presents the stratigraphic columns for units exposed in the area of northern Travis and southern Williamson counties. The Edwards Limestone is up to 120 feet thick in the Project Area and is typically thinner in outcrop due to erosion of its upper surface.

ENVIRONMENTAL BASELINE

The U.S. Fish and Wildlife Service (USFWS) identified potential threats to listed karst invertebrates as including the destruction and/or deterioration of habitat by commercial, residential, and road construction; filling of caves; loss of permeable cover; contamination from such things as septic effluent, sewer leaks, runoff, and pesticides; predation by and competition with non-native fire ants; and vandalism (USFWS 1994).

Generally, habitat requirements for listed karst invertebrates include subsurface void spaces in permanent darkness, moisture input sufficient to maintain high humidity, and a source of organic material from the surface. Organic material can be washed into the void by surface water or brought into the void by small mammals or trogloxene species such as cave crickets ( Ceuthophilus secretus ) and daddy longlegs (Leiobunum townsendii ) (USFWS 1994). Features that can host these organisms include caves, enlarged rock joints, sinkholes, and smaller karst conduits. All seven of the listed karst invertebrate species are believed to be restricted to karst features within the Edwards Limestone and associated formations.

Figure 2. Geologic map of the Project Area.

Figure 3. Generalized Stratigraphy of the Project Area.

In 1992, the USFWS commissioned a study that delineated four geographic zones according to their potential to provide suitable habitat for listed karst invertebrates (Veni 1992). These Karst Zones were based on lithology, distributions of known caves and listed cave fauna, and geologic controls on cave development. The zones were delineated as follows: • Zone 1: Areas known to contain endangered cave species. • Zone 2: Areas having a high probability of endangered or other endemic invertebrate cave fauna. • Zone 3: Areas that probably do not contain endangered cave species. • Zone 4: Areas that do not contain endangered cave species.

As can be seen in Figure 4, the majority of the Project Area would occur within areas delineated as Karst Zone 1. Areas delineated as Karst Zone 2, Zone 3, and Zone 4 occur along the southern end of the Project Area.

Veni (1992) also discussed the overall karst geography of the Austin region, as well as potential geologic and geographic barriers to karst invertebrate dispersal and limits to their distribution. Distinct Karst Fauna Regions (KFRs) were delineated within Travis, Williamson, Hays, and Burnet counties based on “geologic continuity, hydrology, and the distribution of 38 rare troglobites” (USFWS 1994:67). In Travis and Williamson counties they include the North Williamson County, Georgetown, McNeil/Round Rock, Cedar Park, Jollyville Plateau, and Central Austin KFRs. Figure 5 depicts the Project Area in relation to the KFRs. The Project would occur in the Cedar Park, McNeil/Round Rock, and Central Austin KFRs.

Figure 4. USFWS Karst Zones of the Project Area.

Figure 5. Karst Fauna Regions (KFRs) of the Project Area.

The USFWS published a Recovery Plan for the listed karst invertebrates of Travis and Williamson Counties in 1994. This 1994 Recovery Plan identifies down-listing criteria for the listed Travis and Williamson counties karst invertebrates on the permanent protection of Karst Fauna Areas (KFAs). The 1994 Recovery Plan states that KFAs should be selected on the “ability to ensure long-term protection, current level of habitat disturbance, past and present land use, presence of other rare or candidate species, ease of protection (landowner cooperation), and, where applicable, importance to the regional groundwater system” (USFWS 1994:80). At the time the 1994 Recovery Plan was written, there was no specific design for the size and configuration of a KFA. The 1994 Recovery Plan instead provided that those specific determinations should be site-specific, but should include an area large enough to “maintain the integrity of the karst ecosystem on which each species depends” (USFWS 1994:82). The 1994 Recovery Plan recommends that down- listing of an endangered karst invertebrate may be considered when three KFAs within each KFR where it occurs are protected in perpetuity. Although these recovery criteria have not been met for the listed species in the McNeil / Round Rock KFR where the Project is primarily located, recent progress in establishing KFAs suggests that the proposed Project would not jeopardize the continued existence of any of the listed species.

Despite the rapid pace of development in this area, a number of significant conservation actions have occurred to the benefit of the listed karst invertebrates of Travis and Williamson Counties. The Williamson County Regional Habitat Conservation Plan (RHCP) has established nearly 450 acres of dedicated karst preserves that benefit listed species (Table 1). Similarly, the Balcones Canyonlands Conservation Plan (BCCP) protects approximately 30,000 acres in Travis County that includes several thousand acres of potential karst invertebrate habitat in Karst Zones 1 and 2 and multiple caves known to be occupied by these species.

Table 1. Karst invertebrate habitat protected under the Williamson County Regional Habitat Conservation Plan to date.

Number of Estimated Approximate Other Karst Associated Karst Faunal Number Approximate Listed Species Found in Preserve Name Named Number of Preserve Protection Region (KFR) of Caves KFA Acreage Preserve Caves Karst Features Acreage Acreage Texella reyesi, Batrisodes texanus, *Batrisodes Twin Springs KFA North Williamson County 2 2 5 172.2 172.2 0.0 cryptotexanus Beck Preserve McNeil/Round Rock 7 7 7 44.5 0.0 0.0 Texella reyesi Texella reysi, Batrisodes Cobbs Cavern KFA North Williamson County 1 1 11 163.0 163.0 0.0 texanus SW Williamson County Regional Park Georgetown 23 16 39 820.8 0.0 320.0 Texella reyesi Chaos Cave Preserve McNeil/Round Rock 4 4 4 30.0 0.0 0.0 Texella reyesi Big Oak Preserve Cedar Park 1 2 2 10.0 0.0 0.0 None Texella reysi, Batrisodes Priscilla's Well KFA North Williamson County 2 2 2 51.5 51.5 0.0 texanus Woodland Park Cave Preserve North Williamson County 2 2 2 10.2 0.0 0.0 Texella reyesi Texella reysi, Batrisodes Karankawa Cave KFA North Williamson County 8 8 8 61.7 61.7 0.0 texanus Total 50 44 80 1363.9 448.4 320 * Chandler and Reddell (2001) split the listed Batrisodes texanus into two species, B. texanus & B. crypotexanus ; but USFWS does not recognize the split. Species identified as B. cryptotexanus are known from 15 caves, all in Williamson County (Chander and Reddell 2001; email to K. White, 2006).

POTENTIAL FOR ENDANGERED KARST INVERTEBRATES TO OCCUR IN THE PROJECT AREA

Determining whether a geographic area is occupied by listed karst invertebrates is inherently difficult. Habitat for the invertebrates can be highly obscure within the landscape. Cave entrances are often concealed by thick brush or blocked by natural or man-made materials, which have to be removed to make the habitat accessible to researchers. Once accessed, the habitat is a difficult working environment and individuals belonging to listed species are often cryptic within the habitat because they are small (some species are less than 2 millimeters [mm] long), because they occur in small numbers, because they retreat beneath rocks or within inaccessible parts of the cave, or because they enter the humanly accessible part of the cave only on a seasonal basis. Some listed species also have non-listed congeners (other species within the same genus) that occur in the same region. Often these congeners can be difficult to tell apart due to limits in available taxonomic methods. In some instances it can be difficult to tell whether a troglobite recovered from a given cave is a listed species or not. Genetic techniques have been developed for the identification of some listed spiders (Paquin and Hedin 2004, White et al. 2006).

In an attempt to define a due diligence standard that manages the uncertainty inherent to karst studies, the USFWS has developed protocols for determining the presence or absence of listed karst invertebrates (USFWS 2006, 2011, 2014). These protocols provide guidance on when you might be at risk of “taking” a species while conducting karst invertebrate surveys and when it is advisable to have a Section 10(a)(1)(A) permit issued by the USFWS under the ESA to be covered for “take.” The first step in the due diligence process is to survey the surface for karst terraine features that may indicate the potential for habitat in the subsurface. The second step is to investigate any identified karst terraine features for the potential to contain endangered species habitat. This step often involves excavating sinkholes or potential blocked cave entrances. Should potentially suitable habitat be found within a cave, the third step is to conduct a presence/absence survey for listed species within the cave.

SWCA professional geologists conducted a karst terraine feature survey within Project Area between September 2013 to February 2014; with follow-up surveys in October 2014 and March 2015. The pedestrian survey was completed where right of entry was granted by walking parallel transects spaced approximately 50 feet apart. Closer spacing was used where vegetation inhibited clear observation. All potential karst features, including depressions, holes, and animal burrows, were carefully examined for evidence of subsurface extent. A number of techniques were used for this effort, including probing with a digging implement to determine the thickness and consistency of fill material and feeling for the presence of air flow, which may indicate the presence of a subsurface void space. Other techniques included making observations of any notable characteristics of the feature such as the presence of various types of vegetation or a semi-circular burrow mound produced by the activities of small mammals.

The Project Area is highly developed and no potential karst features were observed during the field survey. Construction is currently underway along MoPac Expressway between FM 2222 to US 183. Nearly all land surfaces observed were paved, graded or otherwise previously disturbed and virtually no bedrock outcrop could be seen.

However, several nearby karst features were identified during a literature review, including several caves occupied by endangered karst invertebrates. Figures 6 through 9 depict the locations and occupancy status of seven significant karst features near the Project Area. The closest confirmed locations for any of the listed karst invertebrates are near the northern limits of the Project Area. Both T. reyesi and R. persephone are known to occur in caves associated with the Lakeline Mall Habitat Conservation Plan and the 183A project (Figure 6). The locations of Underline and Lakeline caves are both within 0.2 mile of the Project Area, while Raccoon and Big Oak Cave are directly adjacent to the Project Area. The Project Area actually crosses over Jug Cave, but this feature was sealed during the development of 183A (USFWS 2001).

Lakeline and Underline caves are reported locations for T. reyesi (USFWS 2009a), but both are considered taken under the terms of the Lakeline Mall Habitat Conservation Plan and associated ESA incidental take permit. Texella reyesi and R. persephone are still periodically encountered in Lakeline Cave during biological monitoring visits. Underline Cave has been sealed. Jug and Raccoon caves are reported locations for the R. persephone . Big Oak Cave is a known location for R. persephone , however it is considered impacted by the USFWS because of its close proximity to construction for US 183A.

Additionally, Fossil Cave is located within Hubert C. Schroeter Park, approximately 0.4 mile east of the ROW of US 183 (Figure 7). The cave is a known location for T. reyesi . Marquis Sink is a significant sinkhole with a large surface catchment area that has been land-locked by adjacent development (Figure 8). Marquis Sink has not been excavated, but could indicate the location of habitat for cave fauna. A rumored sinkhole or cave engineered to more-effectively recharge stormwater from an undeveloped lot is located west of the HEB store at the intersection of US 183 and Spicewood Springs Road (Figure 9).

While none of these features are likely to be adversely affected by the Proposed Project, they are illustrative of the potential for karst development within the Project Area. Informal discussions with Texas Commission on Environmental Quality (TCEQ) Edwards Aquifer Protection Program staff indicate that an unknown number of karst features were filled during the construction of US 183 in the Project Area. Most of this construction occurred prior to the development of the Edwards Aquifer Protection Program and protection of karst features was not required, nor were they required to be documented.

Figure 6. Known Endangered Karst Invertebrate Caves Near the Northern End of the Proposed Project Area.

Figure 7. Location Map of Fossil Cave Relative to Project Area.

Figure 8. Location Map of Marquis Sink Relative to Project Area.

POTENTIAL ENDANGERED KARST INVERTEBRATES IN THE PROJECT AREA

The karst terrain feature surveys and desktop reviews completed for the proposed Project did not discover any caves or voids that currently provide habitat for endangered karst fauna within the Project Area. The largely developed condition of land within and adjacent to the Project Area suggests that any potential undiscovered karst invertebrate habitat that may occur within the Project Area is likely to be severely degraded in quality. However, listed karst invertebrate species have been found caves and voids under developed urban areas, so it is possible, but not certain, that voids within the Project Area could be occupied by listed species.2

Seven endangered karst invertebrate species are known from Travis and Williamson counties. Based on their known ranges and distributions, the only endangered taxa with the potential to occur in the Project Area are the Bone Cave harvestman, the Tooth Cave Ground Beetle, the Tooth Cave Spider, and Bee Creek Cave harvestman (Figure 9).

Bee Creek Cave Harvestman (Texella reddelli )

The Bee Creek Cave harvestman was originally described by Goodnight and Goodnight (1967) from a specimen collected from Bee Creek Cave. The USFWS listed the Bee Creek Cave harvestman as endangered on September 16, 1988. It is a light yellowish-brown harvestman with relatively long legs that extend from a small body (2 mm, or less than 1/8 inch, in length). It is an eyeless troglobite that has been found in eight caves within the Jollyville, McNeil/Round Rock, Central Austin, and Rollingwood KFRs. One confirmed location of the Bee Creek Cave harvestman is a cave located east of US 183 north of the intersection of MoPac Expressway (USFWS 2009b).

Bone Cave Harvestman (Texella reyesi )

Bone Cave harvestman is an obligate cave-dwelling harvestman restricted to Travis and Williamson counties (Ubick and Briggs 1992, 2004). The USFWS listed the species as endangered in 1988 on the basis that the species was only known to occur in 5 to 6 localities known in a rapidly development area. Ubick and Briggs (1992) originally described the species when it was separated from Bee Creek Cave harvestman (T. reddelli ). At maturity, Bone Cave harvestman is a pale orange harvestman with a total body length ranging from 0.06 to 0.11 inch (1.41 to 2.67 mm). Retinas are absent and corneal development varies from well-developed to absent (Ubick and Briggs 1992). Ubick and Briggs (1992) state that most specimens of Bone Cave harvestman have been observed in the deep cave environment, past the twilight zone. As of 2009, the USFWS recognized 168 known localities for T. reyesi with an approximate range of 190 square miles (USFWS 2009), and more than 50 percent of these localities are located within currently protected areas. The Bone Cave harvestman is by far the most widespread of the listed karst invertebrates in Travis and Williamson Counties.

Tooth Cave Ground Beetle ( Rhadine persephone )

The Tooth Cave ground beetle was originally described in 1974 along with 16 other central Texas cave beetles (Barr 1974). The USFWS listed the Tooth Cave ground beetle as endangered on September 16, 1988. This ground beetle is the largest (approximately 0.3 inch [8 mm]) and most active and visible (reddish-brown) of the regional endangered karst invertebrate species. The USFWS describes this species as occurring most commonly in areas of deep, uncompacted silt within caves where it digs holes to feed on

2 Endangered karst invertebrates have been detected in karst voids in urbanized areas on the SH 151 project (USFWS 2014) and on the Oblates tract (USFWS 2011) in San Antonio, and in Inner Space Cavern (SWCA 2008) in Williamson County.

cricket eggs (USFWS 1994). The Tooth Cave ground beetle has been at least tentatively confirmed in 57 caves, 48 of which are situated in preserves of various sizes. The Tooth Cave ground beetle is not known to range east of the area surrounding the US 183 and Ranch-to-Market (RM) 620 intersection (SWCA 2008). The boundary between the Cedar Park and McNeil/Round Rock KFRs is based in part on the range of Tooth Cave ground beetle and the species is not thought to occur within the McNeil/Round Rock KFR. The Tooth Cave ground beetle is only likely to occur in the extreme northern end of the Project Area, north of the intersection of US 183 and RM 620.

Tooth Cave Spider (Tayshaneta “Neoleptoneta” myopica )

The Tooth Cave Spider was originally described in 1974 (Gersch 1974) and the USFWS listed it as endangered 1988. This spider is small (1–2 mm) and reclusive and may be found on the underside of very small sheet webs. Taxonomic impediments and its habit of evading detection during surveys kept its known distribution limited to the Jollyville Plateau until very recently (Ledford et al. 2011). Its range overlaps with a closely related species ( T. paraconcinna ) which is not listed. Distinguishing between specimens of these two species may require both genetic analysis and scanning-electron microscopy.

Figure 9. Habitat Map Showing Known Distribution of Listed Karst Species Near Project Area (USFWS 1994a, 2009a,b).

POTENTIAL FOR ADVERSE AFFECT ON ENDANGERED KARST INVERTEBRATES

Troglobitic fauna are vulnerable to impacts from development activities due to their absolute dependence on environmental conditions present only in the caves. The cave environment is relatively monotonous compared to surface habitats and is characterized by stable temperatures close to the mean surface temperature, constant near-saturation humidity, low evaporation rates, and the absence of photosynthetic nutrient production (Barr 1968, Culver 1982). Any activity that breaches the architecture of a cave system has the potential to interrupt the relative stasis of temperature and humidity required by troglobites.

Most threats described below alter the stable physical environment of the cave, alter nutrient input, or introduce substances and/or organisms that have the potential to adversely affect karst invertebrate species.

• Entrances to caves can be filled-in or collapse during development activities or activities for agricultural purposes. Covering cave entrances can alter the physical cave environment, as well as impede or eliminate nutrient input.

• Chemical contamination from ground water and/or surface drainages, including pesticides, fertilizers, sewage, hazardous materials spills, various pipeline leaks, storage tanker leaks, landfills, and urban run-off, could adversely affect karst invertebrates. Trash dumping also may be a source of chemical contamination.

• Altering surface drainage via alterations in topography, impervious cover, etc. could lead to drying of karst features and changes in nutrient inputs.

• Loss or alteration of surface communities can potentially adversely affect karst invertebrates by altering nutrient inputs, altering the stable physical environment of the cave, and introducing potentially harmful organisms. When changes in surface community plant composition occur, there is the potential to alter the type and quality of nutrient input into the cave system from the alteration of vegetation. Moreover, changes in surface plant species composition can in turn alter the surface animal species composition. Alterations in animal species composition may lead to less nutrient input into caves via a decrease of troglophiles and trogloxenes. If the surface plant community is denuded (replaced with impervious cover, left as bare ground, etc.) this could lead to fluctuations in cave temperatures and moisture regimes that are outside the normal range of variability for the system. Lastly, disturbance of the soil may lead to increased density of red imported fire ants ( Solenopsis invicta ) and alter the physical environment of the cave through increased sedimentation.

• Materials excavation operations have the potential to alter the stable physical environment of the cave ecosystem by increasing the number of cave entrances, which could have a drying effect, increase sedimentation, and change water drainage patterns to the system. Furthermore, caves can be completely destroyed through this type of activity.

The Project Area consists almost entirely of previously developed land within one of the most urbanized corridors in the Austin area. Most of the project components are unlikely to adversely affect karst invertebrate habitat.

Direct and Indirect Effects

Direct effects are defined as those effects that are caused by the proposed action at the time of the action [50 CFR§402.02]. Indirect effects are those that are caused by the proposed action and are later in time, but are still reasonably certain to occur [50 CFR§402.02]. The ESA defines the Action Area for the project to be “all areas affected directly or indirectly by the Federal action and not merely the immediate area involved in the action” [50 CFR§402.02]. Direct effects are typically confined to the project footprint, while indirect effects could potentially span a broader area. Indirect effects are caused by the action and are later in time and are reasonably certain to occur [50 CFR§402.02). Indirect effects may occur outside of the area directly affected by the action.

Direct effects to karst invertebrates associated with a roadway project could take the form of direct mortality of individuals resulting from rockfall, collapse, vibration, or penetration of a cavern ceiling or wall. Construction activities associated with the Proposed Project—including grading, boring, and any other soil disturbing activities—would be designed and conducted to minimize and mitigate potential impacts to the extent practicable.

Increased impervious cover could be a source of an indirect effect. Surface water reaching the interiors of caves does so through a diffuse network of fractures which have been buried beneath varying amounts of imported pavement, fill material and topsoil by original highway construction. In total the proposed Project involves 781.6 acres of existing ROW, proposed ROW, and easement. The addition of impervious cover could retard the rate and reduce the amount of recharge through fill material reaching a cave.

In general, roadway construction, especially involving grading and milling, has the potential of producing indirect effects to karst invertebrate habitat by creating new entrances to cave systems and reducing the thickness of the cave ceiling, which could affect the temperature and humidity of the cave. Breach of cave passages during excavation could lead to mortality of karst invertebrates and alteration of temperature and humidity conditions in their habitat. It also creates the potential for the introduction of surface contaminants, including sediment, dust, and stormwater runoff into caves and other connected karst features.

The degradation of groundwater quality due to roadway contaminants or increased sediments in runoff from the Proposed Project entering recharge features may cause indirect hydrological impacts. Indirect hydrological impacts could occur during the construction of the proposed improvements or due to accidental spills relating to vehicle collisions during normal use of the facility following project completion. Operation of the Proposed Project has the potential to create indirect effects if oil and grease from the roadway produce contamination that could infiltrate into caves, however these issues are addressed below.

Due to the lack of survey data indicating the presence of karst features within or adjacent to the Project Area direct and indirect effects are unlikely to occur. Direct and indirect effects would only occur in the unlikely event that a karst void encountered during construction is determined to be occupied by listed species.

The great majority of the project would be constructed on previously disturbed areas above the bedrock surface where karst voids would not occur. However, a review of previous geotechnical investigations in the Project Area indicates the potential to encounter karst voids at depth where bedrock has not been previously disturbed. The likelihood of such an event occurring during construction would be significant only where the deepest subsurface structures would be required to support elevated roadway sections. A very low likelihood exists that an unanticipated void containing habitat for listed species could be encountered during construction. Should this occur, appropriate actions would be taken in accordance with USFWS karst survey protocols and TCEQ regulations. Attachment A contains a detailed estimate of

bedrock excavation within the Project Area and Attachment B contains location maps for expected bedrock excavation.

The potential for impacts to unanticipated karst features would be minimized from both project construction activities and from post-construction spills on the proposed roadway by the implementation of a Water Pollution Abatement Plan (WPAP) and the use of best management practices (BMPs) in accordance with the TCEQ Edwards Aquifer Protection Program (EAPP) and associated Edwards Rules for the entire Project Area. The EAPP is based on state regulations (Texas Administrative Code Chapter 213) stipulating water quality protection for storm water entering the Edwards Aquifer. According to Section 213.1, paragraph 2 of the Texas Administrative Code, Title 30, Part 1, the Edwards Rules and EAPP have been determined to be a non-degradation regulation; therefore, the construction of temporary and permanent BMPs in accordance with an approved WPAP serve to remove sediments and roadway pollutants arising from normal roadway usage and from accidental spills.

Interrelated and Interdependent Effects

Interrelated effects are those effects resulting from actions that are a part of the larger action and depend on the larger action for their justification [50 CFR§402.02]. In the proposed Project, interrelated effects are those effects resulting from actions dependent upon construction and operation of the Proposed Project. Periodic maintenance of the ROW, as well as roadway maintenance and operation could result in interrelated effects. Indirect effects on water quality could be considered interrelated effects. Construction activities including soil disturbance and clearing of vegetation can create conditions that promote infestation by the red-imported fire ant (Taylor et al. 2005; USFWS 1994). Short-term increases in fire ant density may occur as a result of the proposed action. Fire ants were observed throughout the Project Area during the karst terrain feature survey. Interdependent effects are those effects resulting from actions that have no independent utility apart from the action under consideration [50 CFR§402.02]. In the proposed Project, interdependent effects are those effects expected to result from actions that are dependent upon and would not occur in absence of construction of the Proposed Project. Utility relocation could result in interdependent effects associated with the proposed action.

However, due to the lack of survey data indicating the presence of karst features within or adjacent to the Project Area interrelated and interdependent effects are unlikely to occur.

CONCLUSIONS

The Project Area occurs within the known range of four listed karst invertebrate species (Bee Creek Cave harvestman, Bone Cave harvestman, Tooth Cave ground beetle, and Tooth Cave spider). However, the Project Area has been searched (following USFWS protocols for karst invertebrate presence/absence studies) for the presence of karst features that could represent habitat for endangered karst invertebrates and no such features were discovered within the Project Area. Impacts to listed karst species are not expected except in the very unlikely event that a significant karst void is encountered during construction and that void is determined to be occupied by one of the listed species. In order to monitor for undetected habitat encountered during construction activities, karst voids encountered during construction should be evaluated by scientists permitted by the USFWS for karst invertebrate biota surveys (USFWS 2014a). The potential for impacts to unanticipated karst features would be minimized from both project construction activities and from post-construction spills on the proposed roadway by the implementation of a Water Pollution Abatement Plan (WPAP) and the use of best management practices (BMPs) in accordance with the TCEQ Edwards Aquifer Protection Program (EAPP) and associated Edwards Rules for the entire Project Area.

REFERENCES

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Chandler, D. S. and J. R. Reddell. 2001. A review of the ant-like litter beetles found in Texas caves (Coleoptera: Staphylinidae, Pselaphinae). Texas Memorial Museum, Speleological Monographs 5:115-128. Cokendolpher, J.C. 2004. Cicurina spiders from caves in Bexar County, Texas (Araneae: Dictynidae) Texas Memorial Museum Speleological Monograph 6: 13-58. Collins, E. W. 2005 Geologic Map of the West Half of the Taylor 30x60 Quadrangle: Central Texas Urban Corridor, Encompassing Round Rock, Georgetown, Salado, Briggs, Liberty Hill, and Leander. Bureau of Economic Geology, The University of Texas at Austin, Austin, Texas. Culver, D.C. 1982. Cave Life; Evolution and Ecology. Harvard University Press, Cambridge, Massachusetts. Ely, L.M. 1957. Microfauna of the Oakville Formation, LaGrange Area, Fayette County, Texas. University of Texas at Austin M.A., 118 pp. Garner, L.E., K.P. Young, P.U. Rodda, G.L. Dawe, and M.Y. Rogers. 1976. Geologic Map of the Austin Area, Texas. In; Environmental Geology of the Austin Area: an Aid to Urban Planning. Bureau of Economic Geology Report of Investigations No. 86, The University of Texas at Austin. Gertsch, W.J. 1974. The spider family Leptonetidae in North America. The Journal of Arachnology 1:145–203. Goodnight, C.J. and M.L Goodnight. 1967. Opilionids from Texas caves (Opiliones Phalangodidae ). American Museaum Novitates No. 2301. 8 pp. Hedin 2014 Using novel genetic markers and multigenic species delimitation methods to resolve the species status of the cave-dwelling spider species Cicurina wartoni Gertsch from Travis County, Texas. FINAL REPORT FOR USFWS CONTRACT #F13PX00770. Department of Biology, San Diego State University San Diego, CA 92182. Housh, T.B. 2007. Bedrock Geology of Round Rock and Surrounding Areas, Williamson and Travis Counties, Texas. Available at: https://www.lib.utexas.edu/geo/roundrockbedrockgeology/ bedrockgeologyoftheroundrockarea.pdf. Accessed 15 May 2014. Ledford, J. Paquin, P., Cokendolpher, J., Campbell, J., and Griswold, C. 2011. Systematics of the spider genus Neoleptoneta Brignoli, 1972 (Araneae : Leptonetidae ) with a discussion of the morphology and relationships for the North American Leptonetidae . Invertebrate Systematics 25(4) 334-388 http://dx.doi.org/10.1071/IS11014.

Mitchell, R.W. and J.E. Reddell. 1971. The invertebrate fauna of Texas caves. In The Natural History of Texas Caves. Paquin, P., and Hedin, M. 2004. The power and perils of ‘molecular taxonomy’: a case study of eyeless and endangered Cicurina (Aranea: dictynidae) from Texas caves . Molecular Ecology 2004, 13, 3239-3255. Peck, S.B. 1998. A summary of diversity and distribution of the obligate cave-inhabiting faunas of the United States and Canada. Journal of Cave and Karst Studies, April 1998: 18-26. Reddell, J.R. 1993. The Status and Range of Endemic Arthropods from Caves in Bexar County, Texas. Prepared for Texas Parks and Wildlife Department and U.S. Fish and Wildlife Service. 25 October 1993. ———. 1994. The cave fauna of Texas with special reference to the western Edwards Plateau in eds. W. R. Elliott and G. Veni: The Caves and Karst of Texas: A Guidebook for the 1994 Convention of the National Speleological Society with emphasis on the southwestern Edwards Plateau: 31-49. Rodda, P.U. 1970. Geology of the Austin West Quadrangle, Travis County, Texas. University of Texas, Bureau of Economic Geology. Quadrangle Map No.38. SWCA Environmental Consultants (SWCA) 2008. Williamson County Regional Habitat Conservation Plan. Prepared for the Williamson County Conservation Foundation, the Honorable Lisa Birkman, President and Commissioner, Precinct 1. SWCA Project No. 10622-139-AUS. August 15, 2008. Senger, R. K., E.W. Collins, and C.W. Kreitler. 1990. Hydrogeology of the Northern Segment of the Edwards Aquifer. Bureau of Economic Geology, Austin Region, University of Texas at Austin. Taylor, S.J., J.K. Krejca, and M.L. Denight. 2005. Foraging range and habitat use of Ceuthophilus secretus (Orthoptera: Rhaphidophoridae), a key trogloxene in central Texas cave communities. American Midland Naturalist 154:97–113. Travis County Department of Transportation and Natural Resources, Natural Resources and Environmental Quality Division and City of Austin BCP—Austin Water Utility (Travis County, et. al). 2012. Balcones Canyonlands Preserve Karst Monitoring and Management FY 2012 Annual Report (October 1, 2011-September 30, 2012). TxDOT. No date. Karst Decision Flowchart (Federal Projects). Prepared by Environmental Affairs Division of TxDOT, Austin, Texas. Ubick, D and T.S. Briggs. 1992. The harvestman family Phalangodidae. 3. Revision of Texella Goodnight and Goodnight (Opiliones: Laniatores). Texas Memorial Museum, Speleological Monographs, 3:155-240. ———. 2004. The harvestman family Phalangodidae. 5. New records and species of Texella Goodnight and Goodnight (Opiliones: Laniatores). Texas Memorial Museum, Speleological Monographs, 6:101-141. U.S. Fish and Wildlife Service (USFWS). 1994. Recovery plan for endangered karst invertebrate in Travis and Williamson counties, Texas: U.S. Fish and Wildlife Service Region 2. 154 pp. ———. 1994a. Recovery plan for endangered karst invertebrates in Travis and Williamson counties, Texas. 25 August 1994. USFWS Region 2 Office, Albuquerque, NM. 154 pp.

———. 2001. Environmental Assessment for Issuance of two Endangered Species Act Section 10(a)(1)(B) Permits for the Incidental Take of a Troglobitic Ground Beetle ( Rhadine exilis ) and Madla’s Cave Meshweaver ( Cicurina madla ) During the Construction and Operation of Commercial Development on the Approximately 1,000-Acre La Cantera Property, San Antonio, Bexar County, Texas. March 9, 2001. ———. 2006. United States Fish and Wildlife Service, Section 10(a)(1)(A) Scientific Permit Requirements for Conducting Presence/Absence Surveys for Endangered Karst Invertebrates in Central Texas. U.S. Fish and Wildlife Service, Austin Ecological Services Field Office, Austin, Texas. ———. 2009a. 5-Year Review: Bone Cave Harvestman ( Texella reyesi ). USFWS Austin Ecological USFWS Field Office, Austin, TX. 22 pp. ———. 2009b. 5-Year Review: Bee Creek Cave Harvestman (Texella reddelli ). USFWS Austin Ecological USFWS Field Office, Austin, TX. 13 pp. ———. 2009c. 5-Year Review: Tooth Cave Spider ( Neoleptoneta myopica ), Kretschmarr Cave Mold Beetle ( Texamaurops reddelli ), and Tooth Cave Pseudoscorpion ( Tartarocreagris texana ). USFWS Austin Ecological USFWS Field Office, Austin, TX. 15 pp. ———. 2011. United States Fish and Wildlife Service, Section 10(a)(1)(A) Scientific Permit Requirements for Conducting Presence/Absence surveys for Endangered Karst Invertebrates in Central Texas. U.S. Fish and Wildlife Service, Austin Ecological Services Field Office. Revised September 8, 2011. Access 03/17/14 from: https://www.fws.gov/southwest/es/Documents/R2ES/Karst_Survey_Protocols_20110908.pdf ———. 2014a. United States Fish and Wildlife Service, Section 10(a)(1)(A) Scientific Permit Requirements for Conducting Presence/Absence surveys for Endangered Karst Invertebrates in Central Texas. U.S. Fish and Wildlife Service, Austin Ecological Services Field Office. Revised September 8, 2011. Access 11/03/14 from: http://www.fws.gov/southwest/es/Documents/R2ES/Karst_Survey_Procedures_20140508.pdf ______.2014b. Biological Opinion for the Intersection of State Highway 151 and Loop 1604. Bexar County, Texas. Section 7 Consultation Number 02ETAU00-2012-F-0023. 26 August 2014. ______.2014c. Endangered Karst Invertebrate Taxonomy of Central Texas. U.S. Fish and Wildlife Service, Austin Ecological Services Field Office. Revised March 5, 2014. Accessed from: http://www.fws.gov/southwest/es/documents/r2es/bexar_rp_taxo_module.pdf Veni and Associates. 1992. Geologic controls on cave development and the distribution of cave fauna in the Austin, Texas, region. Revised February 1992. USFWS Austin, Texas. 77 pp. Watson, C. 2014. USFWS Presentation of Recovery Status of Austin Area Endangered Karst Invertebrates. Presented at the Karst Conservation Initiative meeting held 24 August 2014. White, K. 2006. Paleohydrology of the Edwards Aquifer Karst and the Evolution of Rare and Endangered Cicurina Cave Spiders, South-Central Texas. University of Mississippi Dissertation. Oxford, Mississippi. Wilson, J.A. 1956. Miocene formations and vertebrate biostratigraphic units. Texas Coastal Plain: American Association of Petroleum Geologists Bulletin. 40:2233-2246.

ATTACHMENT A

EXPECTED BEDROCK REMOVAL QUANTITIES WITHIN PROJECT AREA

PRELIMINARY ESTIMATE OF BEDROCK EXCAVATION ON US 183 NORTH - 492' SOUTH OF SH 45 R.O.W. (STA 837+70) TO LOOP 1

LOCATION/FEATURE BEDROCK AVERAGE DEPTH DESCRIPTION EXCAVATION (CY) (FT) 183 Bridges SB Bridge Over SH 45/RM 620 22 9 Excavation for Drill Shafts for abutments & bents SB Bridge Over Pecan Park Blvd. 11 9 Excavation for Drill Shafts for abutments & bents NB Bridge Over Pecan Park Blvd. 19 15 Excavation for Drill Shafts for abutments & bents SB Bridge Over Anderson Mill Rd 19 15 Excavation for Drill Shafts for abutments & bents NB Bridge Over Anderson Mill Rd 21 17 Excavation for Drill Shafts for abutments & bents SB Bridge Over McNeil Dr 56 10 Excavation for Drill Shafts for abutments & bents NB Bridge Over McNeil Dr 62 9 Excavation for Drill Shafts for abutments & bents SB Bridge Over Oak Knoll Dr 36 15 Excavation for Drill Shafts for abutments & bents NB Bridge Over Oak Knoll Dr 32 22 Excavation for Drill Shafts for abutments & bents SB Bridge Over Duval Rd 41 13 Excavation for Drill Shafts for abutments & bents NB Bridge Over Duval Rd 34 11 Excavation for Drill Shafts for abutments & bents SB Bridge Over Balcones Woods Dr 32 10 Excavation for Drill Shafts for abutments & bents NB Bridge Over Balcones Woods Dr 36 12 Excavation for Drill Shafts for abutments & bents SB Bridge Over Braker Ln 47 29 Excavation for Drill Shafts for abutments & bents NB Bridge Over Braker Ln 41 26 Excavation for Drill Shafts for abutments & bents SB Bridge Over Great Hills Trl 40 26 Excavation for Drill Shafts for abutments & bents NB Bridge Over Great Hills Trl 40 19 Excavation for Drill Shafts for abutments & bents Total for 183 Bridges 589

"Wishbone" Ramps to Existing SH 45 DC'S SB "Wishbone" Ramp Retaining Wall 0 Bedrock too deep NB "Wishbone" Ramp Retaining Wall 0 Bedrock too deep SB "Wishbone" Ramp on Elevated Structure 47 10 Excavation for Drill Shafts beneath the columns NB "Wishbone Ramp" on Elevated Structure 16 10 Excavation for Drill Shafts beneath the columns Total for "Wishbone" Ramps to Existing SH 45 DC'S 63

183 Retaining Walls SB North of McNeil 0 Bedrock too deep SB South of McNeil 0 Bedrock too deep NB North of McNeil 0 Bedrock too deep NB South of McNeil 0 Bedrock too deep SB North of Oak Knoll 14 0.5 Excavation for leveling pad SB South of Oak Knoll 20 0.5 Excavation for leveling pad NB North of Oak Knoll 18 0.5 Excavation for leveling pad NB South of Oak Knoll 27 0.5 Excavation for leveling pad NB South of Oak Knoll 5 0.5 Excavation for leveling pad SB North of Duval 42 0.5 Excavation for leveling pad SB South of Duval 0 Bedrock too deep NB North of Duval 0 Bedrock too deep NB South of Duval 34 0.5 Excavation for leveling pad SB North of Balcones 0 Bedrock too deep SB South of Balcones 14 0.5 Excavation for leveling pad NB North of Balcones 0 Bedrock too deep NB South of Balcones 15 0.5 Excavation for leveling pad PRELIMINARY ESTIMATE OF BEDROCK EXCAVATION ON US 183 NORTH - 492' SOUTH OF SH 45 R.O.W. (STA 837+70) TO LOOP 1

LOCATION/FEATURE BEDROCK AVERAGE DEPTH DESCRIPTION EXCAVATION (CY) (FT) SB North of Braker 0 Bedrock too deep SB South of Braker 8 0.5 Excavation for leveling pad NB North of Braker 0 Bedrock too deep NB South of Braker 0 Bedrock too deep SB North of Great Hills Trl 0 Bedrock too deep SB South of Great Hills Trl 0 Bedrock too deep NB North of Great Hills Trl 0 Bedrock too deep NB South of Great Hills Trl 0 Bedrock too deep Total for 183 Retaining Walls 197

183 Storm Sewer Installation 15,540 2 Proposed 36" storm sewer from SH 45 to Loop 1

Express DCs Retaining Walls SB Express DC (in median of 183) 11 0.5 Excavation for leveling pad NB Express DC (in median of 183) 11 0.5 Excavation for leveling pad Total for Express DCs Retaining Walls 21

Express DCs Bridges NB/SB BRIDGE OVER SB US 183 AND EXIST DC TO LOOP 1 40 20 Drill Shafts for abutments & bents Total for Express DC Bridges 40

Express DCs - Excavation into big hill SB Express DC 0 25 Assumed bedrock is 2' below surface for entire length of the hill NB Express DC 0 25 Assumed bedrock is 2' below surface for entire length of the hill Total for Express DCs Excavation into big hill 0

SBFR (between Loop 360 & Loop 1) adjacent to church 2,580 9 Assumed bedrock is 2' below surface for entire length of cut

Re-aligned South to North U-Turn - Excavation 0 4 Assumed bedrock is 2' below surface

Re-aligned entrance ramp to SB US 183 - Excavation 0 24 Assumed bedrock is 2' below surface

TOTAL BEDROCK EXCAVATION FOR ROAD AND BRIDGE 19,030

TOTAL BEDROCK EXCAVATION FOR WATER QUALITY PONDS & VAULTS 35,582

TOTAL BEDROCK EXCAVATION FOR US 183 NORTH - SH 45 TO LOOP 1 54,612 PRELIMINARY ESTIMATE OF BEDROCK EXCAVATION ON LOOP 1 - US 183 TO RM 2222

LOCATION/FEATURE BEDROCK AVERAGE DEPTH DESCRIPTION EXCAVATION (CY) (FT)

SB Pav Widening & Ret Wall - Existing US 183 DC to Steck Exit 6183 6.5 Assume top of Bedrock is 2' below surface

SB Pavement Widening Near the existing DC from US 183 385 0.8 Assume top of Bedrock is 2' below surface Between Steck Exit and Entrance Ramp South of Steck 1365 2.5 Assume top of Bedrock is 2' below surface Between Entrance Ramp South of Steck & Anderson Lane Bridge 531 1.7 Assume top of Bedrock is 2' below surface Between Anderson Ln Bridge and End of Karst Zone 1 440 1.2 Assume top of Bedrock is 2' below surface Total for SB Pavement Widening 2721

NB Pavement Widening Between the existing DC to US 183 and the North end of the MIP C-D Road 0 0 Most of this area is on fill so no excavation into bedrock Between the North End of the MIP C-D Road and the Steck Ave Bridge 50 0.3 Assume top of Bedrock is 2' below surface Between Steck Ave Bridge and Exit to Steck Ave 107 0.3 Assume top of Bedrock is 2' below surface Between Exit to Steck Ave and End of Karst Zone 1 153 0.3 Assume top of Bedrock is 2' below surface Total for NB Pavement Widening 310

Express Lanes on Elevated Structure in Center of Loop 1 141 10 Excavation for Drill Shafts beneath the columns

TOTAL BEDROCK EXCAVATION FOR LOOP 1 - US 183 TO RM 2222 9,045 BEDROCK EXCAVATION FOR US 183 MAIN LANE BRIDGES (DRILL SHAFTS)

Widening of the existing bridges to the inside along US 183 will require 1 new column in each direction

DRILL SHAFT TOP OF DRILL SHAFT DRILL SHAFT BOTTOM OF DRILL SHAFT ELEVATION AT TOP DEPTH OF DRILL SHAFT LOCATION DESCRIPTION DIAMETER (FT) AREA (SF) ELEVATION (FT) LENGTH (FT) ELEVATION (FT) OF LIMESTONE (FT) IN LIMESTONE (FT) EXCAVATION (CY)

SB BRIDGE OVER SH 45/RM 620

SB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 942.40 32 910.40 918.00 7.6 0.5 SB-Abutment 1 30" Drill Shaft 2.5 4.9 942.32 32 910.32 918.00 7.7 1.4 SB-Bent 2 42" Drill Shaft 3.5 9.6 922.92 17 905.92 920.00 14.1 5.0 SB-Bent 3 42" Drill Shaft 3.5 9.6 922.80 17 905.80 920.00 14.2 5.1 SB-Bent 4 42" Drill Shaft 3.5 9.6 922.70 17 905.70 920.00 14.3 5.1 SB-Bent 5 42" Drill Shaft 3.5 9.6 922.62 17 905.62 920.00 14.4 5.1 SB-Bent 6 42" Drill Shaft 3.5 9.6 922.50 17 905.50 910.00 4.5 SB-Abutment 7 30" Drill Shaft 2.5 4.9 941.70 32 909.70 910.00 0.3 SB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 941.80 32 909.80 910.00 0.2 Avg Depth = 9 22 TOTAL FOR SB BRIDGE OVER SH 45/RM 620

SB BRIDGE OVER PECAN PARK BLVD

SB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 942.82 38 904.82 913.90 9.1 0.6 SB-Abutment 1 30" Drill Shaft 2.5 4.9 942.77 38 904.77 913.90 9.1 1.7 SB-Bent 2 42" Drill Shaft 3.5 9.6 927.05 24 903.05 913.90 10.9 3.9 SB-Bent 3 42" Drill Shaft 3.5 9.6 926.51 24 902.51 912.60 10.1 3.6 SB-Abutment 4 30" Drill Shaft 2.5 4.9 943.89 38 905.89 912.60 6.7 1.2 SB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 944.00 38 906.00 912.60 6.6 0.4 Avg Depth = 9 11 TOTAL FOR SB BRIDGE OVER PECAN PARK BLVD

NB BRIDGE OVER PECAN PARK BLVD

NB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 942.82 38 904.82 917.08 12.3 0.8 N'B-Abutment 1 30" Drill Shaft 2.5 4.9 942.78 38 904.78 917.08 12.3 2.2 NB-Bent 2 42" Drill Shaft 3.5 9.6 927.05 24 903.05 917.08 14.0 5.0 NB-Bent 3 42" Drill Shaft 3.5 9.6 926.51 24 902.51 922.70 20.2 7.2 NB-Abutment 4 30" Drill Shaft 2.5 4.9 943.89 38 905.89 922.70 16.8 3.1 NB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 944.01 38 906.01 922.70 16.7 1.1 Avg Depth = 15 19 TOTAL FOR NB BRIDGE OVER PECAN PARK BLVD

SB BRIDGE OVER ANDERSON MILL RD

SB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 969.30 37 932.30 946.00 13.7 0.9 SB-Abutment 1 30" Drill Shaft 2.5 4.9 969.48 37 932.48 946.00 13.5 2.5 SB-Bent 2 42" Drill Shaft 3.5 9.6 951.49 21 930.49 946.00 15.5 5.5 SB-Bent 3 42" Drill Shaft 3.5 9.6 952.12 21 931.12 949.00 17.9 6.4 SB-Abutment 4 30" Drill Shaft 2.5 4.9 971.01 37 934.01 949.00 15.0 2.7 SB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 970.83 37 933.83 949.00 15.2 1.0 Avg Depth = 15 19 TOTAL FOR SB BRIDGE OVER ANDERSON MILL RD NB BRIDGE OVER ANDERSON MILL RD

NB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 968.25 37 931.25 948.0 16.7 1.1 NB-Abutment 1 30" Drill Shaft 2.5 4.9 968.18 37 931.18 948.0 16.8 3.1 NB-Bent 2 42" Drill Shaft 3.5 9.6 951.57 21 930.57 948.0 17.4 6.2 NB-Bent 3 42" Drill Shaft 3.5 9.6 951.86 21 930.86 949.0 18.1 6.5 NB-Abutment 4 30" Drill Shaft 2.5 4.9 969.00 37 932.00 949.0 17.0 3.1 NB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 969.14 37 932.14 949.0 16.9 1.1 Avg Depth = 17 21 TOTAL FOR NB BRIDGE OVER ANDERSON MILL RD SB BRIDGE OVER MCNEIL DR

SB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 957.13 20 937.13 933 Inside Widening SB-Abutment 1 30" Drill Shaft 2.5 4.9 957.20 30 927.20 933 5.8 1.1 Inside Widening SB-Bent 2 42" Drill Shaft 3.5 9.6 941.91 15 926.91 933 6.1 2.2 Inside Widening SB-Bent 3 42" Drill Shaft 3.5 9.6 942.11 15 927.11 933 5.9 2.1 Inside Widening SB-Bent 4 42" Drill Shaft 3.5 9.6 941.73 15 926.73 934 7.3 2.6 Inside Widening SB-Bent 5 42" Drill Shaft 3.5 9.6 941.79 15 926.79 938 11.2 4.0 Inside Widening SB-Bent 6 42" Drill Shaft 3.5 9.6 942.81 15 927.81 938 10.2 3.6 Inside Widening SB-Bent 7 42" Drill Shaft 3.5 9.6 945.46 20 925.46 938 12.5 4.5 Inside Widening SB-Bent 8 42" Drill Shaft 3.5 9.6 945.83 20 925.83 938 12.2 4.3 Inside Widening SB-Abutment 9 30" Drill Shaft 2.5 4.9 961.17 32 929.17 938 8.8 1.6 Inside Widening SB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 961.18 20 941.18 938 Inside Widening

SB-Abutment 1 30" Drill Shaft 2.5 4.9 955.82 30 925.82 933 7.2 1.3 Outside Widening SB-Bent 2 42" Drill Shaft 3.5 9.6 940.53 15 925.53 933 7.5 2.7 Outside Widening SB-Bent 3 42" Drill Shaft 3.5 9.6 940.73 15 925.73 933 7.3 2.6 Outside Widening SB-Bent 4 42" Drill Shaft 3.5 9.6 940.35 15 925.35 934 8.6 3.1 Outside Widening SB-Bent 5 42" Drill Shaft 3.5 9.6 940.22 15 925.22 938 12.8 4.6 Outside Widening SB-Bent 6 42" Drill Shaft 3.5 9.6 941.35 15 926.35 938 11.7 4.1 Outside Widening SB-Bent 7 42" Drill Shaft 3.5 9.6 944.19 20 924.19 938 13.8 4.9 Outside Widening SB-Bent 8 42" Drill Shaft 3.5 9.6 944.68 20 924.68 938 13.3 4.7 Outside Widening SB-Abutment 9 30" Drill Shaft 2.5 4.9 960.09 32 928.09 938 9.9 1.8 Outside Widening Avg Depth = 10 56 TOTAL FOR SB BRIDGE OVER MCNEIL DR

NB BRIDGE OVER MCNEIL DR

NB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 957.13 20 937.13 933 Inside Widening NB-Abutment 1 30" Drill Shaft 2.5 4.9 957.20 30 927.20 933 5.8 1.1 Inside Widening NB-Bent 2 42" Drill Shaft 3.5 9.6 942.16 15 927.16 933 5.8 2.1 Inside Widening NB-Bent 3 42" Drill Shaft 3.5 9.6 941.9 15 926.90 935 8.1 2.9 Inside Widening NB-Bent 4 42" Drill Shaft 3.5 9.6 940.86 15 925.86 935 9.1 3.3 Inside Widening NB-Bent 5 42" Drill Shaft 3.5 9.6 940.93 15 925.93 936 10.1 3.6 Inside Widening NB-Bent 6 42" Drill Shaft 3.5 9.6 941.91 15 926.91 936 9.1 3.2 Inside Widening NB-Bent 7 42" Drill Shaft 3.5 9.6 942.88 15 927.88 937 9.1 3.2 Inside Widening NB-Bent 8 42" Drill Shaft 3.5 9.6 945.3 20 925.30 937 11.7 4.2 Inside Widening NB-Bent 9 42" Drill Shaft 3.5 9.6 945.32 20 925.32 936 10.7 3.8 Inside Widening NB-Abutment 10 30" Drill Shaft 2.5 4.9 960.94 32 928.94 936 7.1 1.3 Inside Widening NB-Wingwall on Inside 18" Drill Shaft 1.5 1.8 960.98 20 940.98 936 Inside Widening

NB-Abutment 1 30" Drill Shaft 2.5 4.9 955.82 30 925.82 933 7.2 1.3 Outside Widening NB-Bent 2 42" Drill Shaft 3.5 9.6 940.78 15 925.78 933 7.2 2.6 Outside Widening NB-Bent 3 42" Drill Shaft 3.5 9.6 940.53 15 925.53 935 9.5 3.4 Outside Widening NB-Bent 4 42" Drill Shaft 3.5 9.6 939.48 15 924.48 935 10.5 3.7 Outside Widening NB-Bent 5 42" Drill Shaft 3.5 9.6 939.56 15 924.56 936 11.4 4.1 Outside Widening NB-Bent 6 42" Drill Shaft 3.5 9.6 940.76 15 925.76 936 10.2 3.6 Outside Widening NB-Bent 7 42" Drill Shaft 3.5 9.6 941.61 15 926.61 937 10.4 3.7 Outside Widening NB-Bent 8 42" Drill Shaft 3.5 9.6 943.85 20 923.85 937 13.2 4.7 Outside Widening NB-Bent 9 42" Drill Shaft 3.5 9.6 943.75 20 923.75 936 12.3 4.4 Outside Widening NB-Abutment 10 30" Drill Shaft 2.5 4.9 959.28 32 927.28 936 8.7 1.6 Outside Widening

Avg Depth = 9 62 TOTAL FOR NB BRIDGE OVER MCNEIL DR

SB BRIDGE OVER OAK KNOLL DR

SB wingwall on Inside 18" Drill Shaft 1.5 1.8 941.98 27 914.98 923 8.0 0.5 Inside Widening SB-Abutment 1 30" Drill Shaft 2.5 4.9 941.98 32 909.98 923 13.0 2.4 Inside Widening SB-Bent 2 42" Drill Shaft 3.5 9.6 921.92 16 905.92 923 17.1 6.1 Inside Widening SB-Bent 3 42" Drill Shaft 3.5 9.6 919.2 16 903.20 918 14.8 5.3 Inside Widening SB-Abutment 4 30" Drill Shaft 2.5 4.9 933.7 32 901.70 918 16.3 3.0 Inside Widening SB wingwall on Inside 18" Drill Shaft 1.5 1.8 933.7 27 906.70 918 11.3 0.7 Inside Widening

SB-Abutment 1 30" Drill Shaft 2.5 4.9 940.52 32 908.52 923 14.5 2.6 Outside Widening SB-Bent 2 42" Drill Shaft 3.5 9.6 921.13 16 905.13 923 17.9 6.4 Outside Widening SB-Bent 3 42" Drill Shaft 3.5 9.6 918.04 16 902.04 918 16.0 5.7 Outside Widening SB-Abutment 4 30" Drill Shaft 2.5 4.9 933.54 32 901.54 918 16.5 3.0 Outside Widening

Avg Depth = 15 36 TOTAL FOR SB BRIDGE OVER OAK KNOLL NB BRIDGE OVER OAK KNOLL DR

NB wingwall on Inside 18" Drill Shaft 1.5 1.8 942.15 27 915.15 924 8.9 0.6 Inside Widening NB-Abutment 1 30" Drill Shaft 2.5 4.9 942.15 32 910.15 924 13.9 2.5 Inside Widening NB-Bent 2 42" Drill Shaft 3.5 9.6 923.03 16 907.03 924 17.0 6.0 Inside Widening NB-Bent 3 42" Drill Shaft 3.5 9.6 920.38 16 904.38 918 13.6 4.9 Inside Widening NB-Abutment 4 30" Drill Shaft 2.5 4.9 935.17 32 903.17 918 14.8 2.7 Inside Widening NB wingwall on Inside 18" Drill Shaft 1.5 1.8 935.17 27 908.17 918 9.8 0.6 Inside Widening

NB-Abutment 1 30" Drill Shaft 2.5 4.9 943.61 32 911.61 924 12.4 2.3 Outside Widening NB-Bent 2 42" Drill Shaft 3.5 9.6 924.5 16 908.50 924 15.5 5.5 Outside Widening NB-Bent 3 42" Drill Shaft 3.5 9.6 921.81 16 905.81 918 12.2 4.3 Outside Widening NB-Abutment 4 30" Drill Shaft 2.5 4.9 936.63 32 904.63 918 13.4 2.4 Outside Widening

Avg Depth = 22 32 TOTAL FOR NB BRIDGE OVER OAK KNOLL SB BRIDGE OVER DUVAL RD

SB-Abutment 1 30" Drill Shaft 2.5 4.9 867.32 35 832.32 850 17.7 3.2 Inside Widening SB-Bent 2 42" Drill Shaft 3.5 9.6 851.09 13 838.09 850 11.9 4.2 Inside Widening SB-Bent 3 42" Drill Shaft 3.5 9.6 851.77 14 837.77 849 11.2 4.0 Inside Widening SB-Abutment 4 30" Drill Shaft 2.5 4.9 868.96 32 836.96 849 12.0 2.2 Inside Widening

SB-Abutment 1 30" Drill Shaft 2.5 4.9 867.32 35 832.32 850 17.7 6.4 Outside Widening (Requires 2 drill shafts for 4th GP lane) SB-Bent 2 42" Drill Shaft 3.5 9.6 851.09 13 838.09 850 11.9 8.5 Outside Widening (Requires 2 drill shafts for 4th GP lane) SB-Bent 3 42" Drill Shaft 3.5 9.6 851.77 14 837.77 849 11.2 8.0 Outside Widening (Requires 2 drill shafts for 4th GP lane) SB-Abutment 4 30" Drill Shaft 2.5 4.9 868.96 32 836.96 849 12.0 4.4 Outside Widening (Requires 2 drill shafts for 4th GP lane) Avg Depth = 13 41 TOTAL FOR SB BRIDGE OVER DUVAL RD

NB BRIDGE OVER DUVAL RD

NB-Abutment 1 30" Drill Shaft 2.5 4.9 868.49 35 833.49 844 10.5 1.9 Inside Widening NB-Bent 2 42" Drill Shaft 3.5 9.6 851.26 13 838.26 844 5.7 2.0 Inside Widening NB-Bent 3 42" Drill Shaft 3.5 9.6 852.61 14 838.61 852 13.4 4.8 Inside Widening NB-Abutment 4 30" Drill Shaft 2.5 4.9 870.12 32 838.12 852 13.9 2.5 Inside Widening

NB-Abutment 1 30" Drill Shaft 2.5 4.9 868.49 35 833.49 844 10.5 3.8 Outside Widening (Requires 2 drill shafts for 4th GP lane) NB-Bent 2 42" Drill Shaft 3.5 9.6 851.26 13 838.26 844 5.7 4.1 Outside Widening (Requires 2 drill shafts for 4th GP lane) NB-Bent 3 42" Drill Shaft 3.5 9.6 852.61 14 838.61 852 13.4 9.5 Outside Widening (Requires 2 drill shafts for 4th GP lane) NB-Abutment 4 30" Drill Shaft 2.5 4.9 870.12 32 838.12 852 13.9 5.0 Outside Widening (Requires 2 drill shafts for 4th GP lane) Avg Depth = 11 34 TOTAL FOR NB BRIDGE OVER DUVAL RD

SB BRIDGE OVER BALCONES WOODS DR

SB-Abutment 1 30" Drill Shaft 2.5 4.9 882.49 28 854.49 864 9.4 1.7 Inside Widening SB-Bent 2 42" Drill Shaft 3.5 9.6 866.40 11 855.40 864 8.6 3.1 Inside Widening SB-Bent 3 42" Drill Shaft 3.5 9.6 865.82 11 854.82 863 8.2 2.9 Inside Widening SB-Abutment 4 30" Drill Shaft 2.5 4.9 881.00 28 853.00 863 10.0 1.8 Inside Widening

SB-Abutment 1 30" Drill Shaft 2.5 4.9 880.72 28 852.72 864 11.19 4.1 Outside Widening (Requires 2 drill shafts for 4th GP lane) SB-Bent 2 42" Drill Shaft 3.5 9.6 864.66 11 853.66 864 10.34 7.4 Outside Widening (Requires 2 drill shafts for 4th GP lane) SB-Bent 3 42" Drill Shaft 3.5 9.6 864.53 11 853.53 863 9.47 6.7 Outside Widening (Requires 2 drill shafts for 4th GP lane) SB-Abutment 4 30" Drill Shaft 2.5 4.9 879.31 28 851.305 863 11.695 4.3 Outside Widening (Requires 2 drill shafts for 4th GP lane) Avg Depth = 10 32 TOTAL FOR SB BRIDGE OVER BALCONES WOODS DR

NB BRIDGE OVER BALCONES WOODS DR

NB-Abutment 1 30" Drill Shaft 2.5 4.9 883.57 31 852.57 864 11.4 2.1 Inside Widening NB-Bent 2 42" Drill Shaft 3.5 9.6 865.47 12 853.47 864 10.5 3.8 Inside Widening NB-Bent 3 42" Drill Shaft 3.5 9.6 865.30 12 853.30 867 13.7 4.9 Inside Widening NB-Abutment 4 30" Drill Shaft 2.5 4.9 882.05 29 853.05 867 14.0 2.5 Inside Widening

NB-Abutment 1 30" Drill Shaft 2.5 4.9 885.33 31 854.33 864 9.67 3.5 Outside Widening (Requires 2 drill shafts for 4th GP lane) NB-Bent 2 42" Drill Shaft 3.5 9.6 867.20 12 855.2 864 8.8 6.3 Outside Widening (Requires 2 drill shafts for 4th GP lane) NB-Bent 3 42" Drill Shaft 3.5 9.6 866.59 12 854.59 867 12.41 8.8 Outside Widening (Requires 2 drill shafts for 4th GP lane) NB-Abutment 4 30" Drill Shaft 2.5 4.9 883.76 29 854.76 867 12.24 4.4 Outside Widening (Requires 2 drill shafts for 4th GP lane) Avg Depth = 12 36 TOTAL FOR NB BRIDGE OVER BALCONES WOODS DR

SB BRIDGE OVER BRAKER LN

SB wingwall on Inside 18" Drill Shaft 1.5 1.8 882.95 46 836.946 865 28.1 1.8 Inside Widening SB-Abutment 1 30" Drill Shaft 2.5 4.9 882.70 46 836.70 865 28.3 5.1 Inside Widening SB-Bent 2 30" Drill Shaft 2.5 4.9 865.31 29 836.31 865 28.7 5.2 Inside Widening SB-Bent 3 30" Drill Shaft 2.5 4.9 865.49 26 839.49 871 31.5 5.7 Inside Widening SB-Abutment 4 30" Drill Shaft 2.5 4.9 883.12 42 841.12 870 28.9 5.2 Inside Widening SB wingwall on Inside 18" Drill Shaft 1.5 1.8 882.87 42 840.874 870 29.1 1.9 Inside Widening

SB-Abutment 1 30" Drill Shaft 2.5 4.9 881.52 46 835.52 865 29.5 5.4 Outside Widening (For 4th GP lane) SB-Bent 2 30" Drill Shaft 2.5 4.9 866.16 29 837.16 865 27.8 5.1 Outside Widening (For 4th GP lane) SB-Bent 3 30" Drill Shaft 2.5 4.9 865.88 26 839.88 871 31.1 5.7 Outside Widening (For 4th GP lane) SB-Abutment 4 30" Drill Shaft 2.5 4.9 882.04 42 840.04 870 30.0 5.4 Outside Widening (For 4th GP lane) Avg Depth = 29 47 TOTAL FOR SB BRIDGE OVER BRAKER LN

NB BRIDGE OVER BRAKER LN

NB wingwall on Inside 18" Drill Shaft 1.5 1.8 882.99 46 836.99 862 25.0 1.6 Inside Widening NB-Abutment 1 30" Drill Shaft 2.5 4.9 882.75 46 836.75 862 25.3 4.6 Inside Widening NB-Bent 2 30" Drill Shaft 2.5 4.9 867.23 29 838.23 862 23.8 4.3 Inside Widening NB-Bent 3 30" Drill Shaft 2.5 4.9 866.90 26 840.90 870 29.1 5.3 Inside Widening NB-Abutment 4 30" Drill Shaft 2.5 4.9 883.81 42 841.81 866 24.2 4.4 Inside Widening NB wingwall on Inside 18" Drill Shaft 1.5 1.8 882.84 42 840.84 866 25.2 1.6 Inside Widening

NB-Abutment 1 30" Drill Shaft 2.5 4.9 881.69 46 835.69 862 26.3 4.8 Outside Widening (For 4th GP lane) NB-Bent 2 30" Drill Shaft 2.5 4.9 866.16 29 837.16 862 24.8 4.5 Outside Widening (For 4th GP lane) NB-Bent 3 30" Drill Shaft 2.5 4.9 865.88 26 839.88 870 30.1 5.5 Outside Widening (For 4th GP lane) NB-Abutment 4 30" Drill Shaft 2.5 4.9 881.92 42 839.92 866 26.1 4.7 Outside Widening (For 4th GP lane)

Avg Depth = 26 41 TOTAL FOR NB BRIDGE OVER BRAKER LN

SB BRIDGE OVER GREAT HILLS TRL

SB wingwall on Inside 18" Drill Shaft 1.5 1.8 904.33 46 858.33 889 30.7 2.0 Inside Widening SB-Abutment 1 30" Drill Shaft 2.5 4.9 905.02 46 859.02 889 30.0 5.4 Inside Widening SB-Bent 2 30" Drill Shaft 2.5 4.9 885.73 27 858.73 887 28.3 5.1 Inside Widening SB-Bent 3 30" Drill Shaft 2.5 4.9 886.31 27 859.31 891 31.7 5.8 Inside Widening SB-Abutment 4 30" Drill Shaft 2.5 4.9 904.00 46 858.00 891 33.0 6.0 Inside Widening SB wingwall on Inside 18" Drill Shaft 1.5 1.8 903.23 46 857.23 891 33.8 2.2 Inside Widening

SB-Abutment 1 30" Drill Shaft 2.5 4.9 906.99 46 860.99 889 28.0 5.1 Outside Widening (For 4th GP lane) SB-Bent 2 30" Drill Shaft 2.5 4.9 907.20 27 880.20 887 6.8 1.2 Outside Widening (For 4th GP lane) SB-Bent 3 30" Drill Shaft 2.5 4.9 907.05 27 880.05 891 11.0 2.0 Outside Widening (For 4th GP lane) SB-Abutment 4 30" Drill Shaft 2.5 4.9 906.66 46 860.66 891 30.3 5.5 Outside Widening (For 4th GP lane)

Avg Depth = 26 40 TOTAL FOR SB BRIDGE OVER GREAT HILLS TRL

NB BRIDGE OVER GREAT HILLS TRL

NB wingwall on Inside 18" Drill Shaft 1.5 1.8 904.08 45 859.08 883 23.9 1.6 Inside Widening NB-Abutment 1 36" Drill Shaft 3 7.1 904.08 45 859.08 883 23.9 6.3 Inside Widening NB-Bent 2 36" Drill Shaft 3 7.1 904.15 27 877.15 884 6.9 1.8 Inside Widening NB-Bent 3 36" Drill Shaft 3 7.1 902.76 26 876.76 885 8.2 2.2 Inside Widening NB-Abutment 4 36" Drill Shaft 3 7.1 902.66 43 859.66 886 26.3 6.9 Inside Widening NB wingwall on Inside 18" Drill Shaft 1.5 1.8 902.66 43 859.66 886 26.3 1.7 Inside Widening

NB-Abutment 1 36" Drill Shaft 3 7.1 901.40 45 856.40 883 26.6 7.0 Outside Widening (For 4th GP lane) NB-Bent 2 36" Drill Shaft 3 7.1 901.31 27 874.31 884 9.7 2.5 Outside Widening (For 4th GP lane) NB-Bent 3 36" Drill Shaft 3 7.1 900.61 26 874.61 885 10.4 2.7 Outside Widening (For 4th GP lane) NB-Abutment 4 36" Drill Shaft 3 7.1 899.66 43 856.66 886 29.3 7.7 Outside Widening (For 4th GP lane)

Avg Depth = 19 40 TOTAL FOR NB BRIDGE OVER GREAT HILLS TRL

589 TOTAL FOR BRIDGES BEDROCK EXCAVATION FOR WISHBONE RAMP RETAINING WALLS

The boring logs at the US 183 bridge over Lake Creek Pkwy show the bedrock to be 6'-10' below the surface so no excavation of bedrock required for the retaining walls

Dimensions of leveling pad LOCATION Begin Sta End Sta Length Width Depth EXCAVATION DESCRIPTION FT FT FT CY

SB Wishbond Ramp 860+15. 876+00. 1585 1 0.5 0.0 Portion of SB Wishbone Ramp on retaining wall (assume retaining walls start just south of the bridge over Lake Creek Pkwy) NB Wishbone Ramp 860+15. 876+00. 1585 1 0.5 0.0 Portion of NB Wishbone Ramp on retaining wall (assume retaining walls start just south of the bridge over Lake Creek Pkwy)

0 Total Excavation for the Wishbone Ramp retaining walls

BEDROCK EXCAVATION FOR SB WISHBONE RAMP ON ELEVATED STRUCTURE

Assume 6, 8'-10' wide columns will be needed for the SB wishbone ramp Assume drill shafts will go 10' into bedrock

DRILL SHAFT DEPTH OF DRILL SHAFT LOCATION DESCRIPTION DIAMETER AREA IN LIMESTONE EXCAVATION FT SF FT CY

Column 1 (right of outside lane on SB 183) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 2 (in median of 183) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 3 (in median of 183) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 4 (in median of 183) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 5 (in median of 183) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 6 (in median of 183) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer

47 Total Excavation for Wishbone Ramp Bridge over SB US 183

BEDROCK EXCAVATION FOR NB WISHBONE RAMP BRIDGE ON ELEVATED STRUCTURE

Assume 2, 8'-10' wide columns will be needed for the NB wishbone ramp (4 other columns counted under SB excavation) Assume drill shafts will go 10' into bedrock DRILL SHAFT DEPTH OF DRILL SHAFT

LOCATION DESCRIPTION DIAMETER AREA IN LIMESTONE EXCAVATION FT SF FT CY

Column 1 (right of outside lane on NB 183) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 2 (in median of 183) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer

16 Total Excavation for Wishbone Ramp Bridge over NB US 183 BEDROCK EXCAVATION FOR US 183 PROPOSED RETAINING WALLS

Assume the retaining wall leveling pad is in bedrock

Dimensions of leveling pad LOCATION Begin Sta End Sta Length Width Depth into limestone EXCAVATION DESCRIPTION FT FT FT CY SB-North of McNeil Rd 965+53. 986+03. 2050 1 0.5 North side of McNeil Rd bridge Limestone appears to be 3' below surface (No excavation here) SB-South of McNeil Rd 993+11. 1+67. 814 1 0.5 South side of McNeil Rd bridge Limestone appears to be 11' below surface (No excavation here) NB-North of McNeil Rd 977+10. 986+03. 893 1 0.5 North side of McNeil Rd bridge Limestone appears to be 3' below surface (No excavation here) NB-South of McNeil Rd 994+10. 2+67. 797 1 0.5 South side of McNeil Rd bridge Limestone appears to be 10' below surface (No excavation here)

SB-North of Oak Knoll Dr 20+10. 27+83. 773 1 0.5 14.3 North side of Oak Knoll Dr bridge Limestone appears to be 1' below surface SB-South of Oak Knoll Dr 31+11. 41+71. 1060 1 0.5 19.6 South side of Oak Knoll Dr bridge Limestone appears to be 1' below surface NB-North of Oak Knoll Dr 18+03. 27+83. 980 1 0.5 18.1 North side of Oak Knoll Dr bridge Limestone appears to be 1' below surface NB-South of Oak Knoll Dr 31+11. 45+42. 1431 1 0.5 26.5 South side of Oak Knoll Dr bridge Limestone appears to be 1' below surface NB-South of Oak Knoll Dr 47+29. 49+96. 267 1 0.5 4.9 South side of Oak Knoll Dr bridge (south of on-ramp) Limestone appears to be 1' below surface

SB-North of Duval 62+29. 85+00. 2271 1 0.5 42.1 North side of Duval bridge Limestone appears to be 1' below surface SB-South of Duval 88+05. 100+00. 1195 1 0.5 South side of Duval bridge Limestone appears to be 6' below surface (No excavation here) NB-North of Duval 60+00. 85+00. 2500 1 0.5 North side of Duval bridge Limestone appears to be 4' below surface (No excavation here) NB-South of Duval 88+05. 106+48. 1843 1 0.5 34.1 South side of Duval bridge Limestone appears to be 1' below surface

SB-North of Balcones 110+71. 125+79. 1508 1 0.5 North side of Balcones bridge Limestone appears to be 4' below surface (No excavation here) SB-South of Balcones 129+06. 138+15. 909 1 0.5 16.8 South side of Balcones bridge Limestone appears to be 1' below surface NB-North of Balcones 103+32. 126+06. 2274 1 0.5 North side of Balcones bridge Limestone appears to be 4' below surface (No excavation here) NB-South of Balcones 129+06. 139+04. 998 1 0.5 18.5 South side of Balcones bridge Limestone appears to be 1' below surface

SB-North of Braker 146+13. 153+06. 693 1 0.5 North side of Braker bridge Limestone appears to be 5' below surface (No excavation here) SB-South of Braker 156+11. 160+32. 421 1 0.5 7.8 South side of Braker bridge Limestone appears to be 1' below surface NB-North of Braker 146+91. 153+30. 639 1 0.5 North side of Braker bridge Limestone appears to be 5' below surface (No excavation here) NB-South of Braker 156+34. 161+00. 466 1 0.5 South side of Braker bridge Limestone appears to be 6' below surface (No excavation here)

SB-North of Great Hills Trl 167+32. 176+30. 898 1 0.5 North side of Great Hills Trl bridge Limestone appears to be 2.5' below surface (No excavation here) SB-South of Great Hills Trl 179+33. 183+42. 409 1 0.5 South side of Great Hills Trl bridge Limestone appears to be 2' below surface (No excavation here) NB-North of Great Hills Trl 168+69. 176+23. 754 1 0.5 North side of Great Hills Trl bridge Limestone appears to be 2' below surface (No excavation here) NB-South of Great Hills Trl 179+47. 187+48. 801 1 0.5 South side of Great Hills Trl bridge Limestone appears to be 2.5' below surface (No excavation here)

203 Total Excavation for the US 183 retaining walls BEDROCK EXCAVATION FOR NEW STORM SEWER INSTALLATION

Assume excavation would be for a new 36" storm sewer from SH 45 to Loop 1

Dimensions of storm sewer LOCATION Begin Sta End Sta Length Width Depth into Bedrock EXCAVATION DESCRIPTION FT FT FT CY

US 183-Begin Project to Sta Equation 815+00. 999+58.07 18458 5 2.0 6,836.3 From Start of Project to Station Equation (Bedrock seems to average about 3' deep throughout the entire project) US 183-Sta Equation to Loop 1 +. 235+00. 23500 5 2.0 8,703.7 From Station equation to Loop 1 (Bedrock seems to average about 3' deep throughout the entire project)

15,540 Total excavation for storm sewer installation BEDROCK EXCAVATION FOR THE EXPRESS DC RETAINING WALLS

Assume the retaining wall leveling pad is in bedrock Dimensions of leveling pad LOCATION Begin Sta End Sta Length Width Depth EXCAVATION DESCRIPTION FT FT FT CY

SB Express DC 204+50. 216+00. 1150 1 0.5 10.6 Portion of DC with Retaining Wall (No bore data in this area so we will assume half of the wall leveling pad would be in bedrock) NB Express DC 204+50. 216+00. 1150 1 0.5 10.6 Portion of DC with Retaining Wall (No bore data in this area so we will assume half of the wall leveling pad would be in bedrock)

21 Total Excavation for the Express DC retaining walls

BEDROCK EXCAVATION FOR THE PORTION OF THE EXPRESS DC LOCATED IN THE BIG HILL BETWEEN 360 AND LOOP 1

Assume the bedrock is 2' below the existing surface for entire length of the hill Length Width Depth EXCAVATION FT FT FT CY

SB Express DC in big cut south of 360 48+16. 62+30. 1414 28 20 NB Express DC in big cut south of 360 48+16. 62+30. 1414 28 20 DC configuration has been changed to be all elevated, so excavation into hill will not be needed 0 Total Excavation for the portion of the Express DC that cuts into big hill between 360 and Loop 1

BEDROCK EXCAVATION FOR EXPRESS LANES DC BRIDGE OVER SB US 183-2 SPANS

DRILL SHAFT DEPTH OF DRILL SHAFT LOCATION DESCRIPTION DIAMETER AREA DRILL SHAFT LENGTH IN LIMESTONE EXCAVATION FT SF FT FT CY

Abutment in US 183 median 18" Drill Shaft 1.5 1.8 20 15 1.0 Assume 1 drill shaft 30" Drill Shaft 2.5 4.9 30 25 13.6 Assume 3 drill shafts Columns between 2 spans 42" Drill Shaft 3.5 4.9 25 20 10.9 Assume 3 drill shafts Abutment on outside part of US 183 18" Drill Shaft 1.5 1.8 20 15 1.0 Assume 1 drill shaft 30" Drill Shaft 2.5 4.9 30 25 13.6 Assume 3 drill shafts Avg Depth = 20 40 Total Excavation for Express Lanes DC Bridge over SB US 183 BEDROCK EXCAVATION FOR THE PORTION OF THE SOUTH TO NORTH U-TURN LOCATED IN KARST ZONE 1

Assume the bedrock is 2' below the existing surface for entire length of the U-turn Length Width Average Depth EXCAVATION FT FT FT CY

Portion of U-Turn in cut 108+43. 108+80. 37 20 4 Need for U-turn construction has been eliminated 0 Total Excavation for the portion of the U-Turn in cut BEDROCK EXCAVATION FOR THE PORTION OF THE SB FR (BETWEEN LOOP 360 & LOOP 1) LOCATED IN KARST ZONE 1

Assume the bedrock is 2' below the existing surface Length Width Average Depth of cut EXCAVATION FT FT FT CY

Portion of SB FR in cut 202+73. 210+47. 774 10 9 2,580.0 Portion of SBFR in cut (includes adjacent retaining wall)

2,580 Total Excavation for the portion of the SBFR in cut BEDROCK EXCAVATION FOR THE PORTION OF RAMP L-2 LOCATED IN KARST ZONE 1

Assume the bedrock is 2' below the existing surface for entire length of the ramp Length Width Average Depth EXCAVATION FT FT FT CY

Portion of Ramp L-2 in cut 55+25. 66+72. 1147 26 24 Need for realignment of Ramp L-2 has been eliminated 0 Total Excavation for the portion of Ramp L-2 in cut BEDROCK EXCAVATION FOR THE PAVEMENT WIDENING ON LOOP 1

Assume the bedrock is 2' below the existing surface for entire length of Loop 1 (the bore logs on the existing plans, from 1977, are not legible) Average Depth LOCATION Begin Sta End Sta Length Area (from plan dgn) of Excavation into Bedrock EXCAVATION DESCRIPTION FT SF FT CY

SB Pavement Widening 211+13. 216+45. 12981 0.8 384.6 Average depth of excavation into bedrock determined from MIP x-sections 236+34. 257+80. 14742 2.5 1,365.0 Average depth of excavation into bedrock determined from MIP x-sections 257+80. 273+21. 8432 1.7 530.9 Average depth of excavation into bedrock determined from MIP x-sections 277+33. 289+39. 9892 1.2 439.6 Average depth of excavation into bedrock determined from MIP x-sections

2,720 Total Excavation for Widening the Pavement on SB Loop 1

NB pavement widening 222+39. 235+96. 23425 0.0 0.0 Most of this area is on fill so no excavation into bedrock 235+96. 243+07. 4527 0.3 50.3 Average depth of excavation into bedrock determined from MIP x-sections 249+85. 265+92. 9587 0.3 106.5 Average depth of excavation into bedrock determined from MIP x-sections 271+07. 290+43. 13770 0.3 153.0 Average depth of excavation into bedrock determined from MIP x-sections

310 Total Excavation for Widening the Pavement on NB Loop 1

BEDROCK EXCAVATION FOR RETAINING WALL & PAVEMENT WIDENING BETWEEN SB AUX LANE AND SB FRONTAGE RD (BETWEEN EXIST DC FROM US 183 AND STECK EXIT)

Assume the bedrock is 2' below the existing surface for entire length of Loop 1 (the bore logs on the existing plans, from 1977, are not legible)

Average Depth LOCATION Begin Sta End Sta Length Width Area (from plan dgn) of Excavation into Bedrock EXCAVATION DESCRIPTION FT FT SF FT CY

SB-Between US 183 Existing DC & Exit to Steck 216+45. 237+00. 23787 6.5 5,726.5 Excavation for pavement widening and retaining wall between SB Aux lane and SB FR RD SB-Between US 183 Existing DC & Exit to Steck 216+45. 237+00. 2055 6 1.0 456.7 Excavation for leveling pad of retaining wall between SB Aux lane and SB FR RD

6,183 Total Excavation for Retaining Wall & Pavement Widening

BEDROCK EXCAVATION FOR EXPRESS LANES DC COLUMNS IN THE CENTER OF LOOP 1

Assume 18, 8'-10' wide columns will be needed for the elevated portion of the Express DC in the Loop 1 median (columns spaced at 120') Assume drill shafts will go 10' into bedrock DRILL SHAFT DEPTH OF DRILL SHAFT LOCATION DESCRIPTION DIAMETER AREA IN LIMESTONE EXCAVATION FT SF FT CY

Column 1 (supports NB & SB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 2 (supports NB & SB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 3 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 4 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 5 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 6 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 7 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 8 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 9 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 10 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 11 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 12 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 13 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 14 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 15 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 16 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 17 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer Column 18 (supports NB Express DC) 36" Drill Shaft 3 7.1 10 7.9 Assume 3 drill shafts per column and that excavation would occur to a depth of 10' into the bedrock layer

141 Total Excavation for Express Lanes DC Columns in the Center of Loop 1 PRELIMINARY ESTIMATE OF BEDROCK EXCAVATION FOR WATER QUALITY PONDS & VAULTS ON US 183 NORTH - SH 45 TO LOOP 1

Estimated Total Capture Depth of Additional Estimated Not Deeper Estimated Lowest Likely in Drainage Volume [WQV+ Existing BMP Elevation of Excavation BMP Area Excavation Than BMP Location Existing BMP Suggested Solution Excavation Excavation Excavation Volume Notes Disturbed Area Label Contingency] (cu Area*** (sq ft) Bedrock (ft) in Bedrock Needed (sq Volume (cu Existing Depth (ft) Elevation Area ft) (ft) ft) yd) Control (MSE) Lake Creek Vaults Need to dig through the existing fill to A North of Lake Creek Pkwy 10,994 8,250 Expand Pond 1B, depth of 9.25 ft 16 914 922 8 595 220 x x (Underground)** reach vault elevation Lake Creek Pkwy to Hidden Hymeadow Vaults Need to dig through the existing fill to B 10,994 6,660 Expand Ponds 2A and 2B, depth of 9.25 ft 15 914 934 20 1,190 826 x x Meadow Dr (Underground) reach vault elevation Hidden Meadow Dr to Pond Springs Pond Expand WQ pond, added surface area of C 16,932 20,019 9 911 941 30 3,387 1,411 x x Anderson Mill Rd (sed/fil) 3400 sq ft, WQ depth = 5 ft Anderson Mill Rd to Hunters Expand wet pond, added surface area of Need to dig deeper than the permanent D Woods Pond (wet) 24,734 98,139 12 908 940 32 6,351 3,528 x x Chase Dr 6200 sq ft, WQ depth = 4 ft pool elevation of 915.82 Install WQ pond under McNeil Dr / Hunters Chase Dr to E Rattan Creek/No controls 28,377 0 Spicewood Springs Rd bridge, WQ depth = 12 924 936 12 14,200 6,311 x na Barrington Way 10 ft Install bioretention swale on available green Hunters Chase Dr to This excavation also accounts for the E Rattan Creek/No controls 28,377 0 space along 183N, 1 ft deep, 18in 2 936 938 2 18,500 500 x na Barrington Way installment of underdrains biofiltration media Hunters Chase Dr to Install WQ pond in lot next to Pond Springs E Rattan Creek/No controls 28,377 0 12 924 936 12 4,730 2,075 x na Barrington Way Rd totaling 4667 sq ft, WQ depth = 10 ft West Cow Path Pond Expand WQ pond, added surface area of Need to dig deeper due to existing F Barrington Way to Angus Rd 88,521 40,472 12 821 849 28 14,754 8,197 x x (sed/fil) 14754 sq ft , WQ depth = 6 ft contours, WQV Elevation = 830.9 ft Need to dig deeper due to existing Expand WQ pond, added surface area of contours, WQV Elevation = 830.9 ft, G Angus Rd to Stonelake Blvd Seton Pond (sed/fil) 83,065 23,420 20 835 865 30 10,383 9,614 x x 10383 sq ft, WQ depth = 8 ft existing pond is 16 ft deep to account for pipe network South of Stonelake Blvd to Mopac Ponds/No Install 1 WQ ponds by Mopac/183 H 31,320 0 6 769 795 26 10,440 2,900 x na Mopac Controls intersection, WQ depth = 3 ft TOTAL BEDROCK EXCAVATION FOR WATER QUALITY PONDS & VAULTS = 35,582 CU YDS

* WQV for detention pond estimated by subtracting Hymeadow vaults WQV and subtracting from total WQV north of Lake Creek Pkwy (48450 cu ft) ** Lake Creek vaults' WQV estimated from Hymeadow vaults *** estimated, exact areas were not found in WPAPs for some of these

THE FIRST SUGGESTED SOLUTION WOULD BE TO INCREASE THE AREA OF EXISTING CONTROLS. HOWEVER WITHOUT DESIGNING THE PONDS,

10/3/2014

ATTACHMENT B

LOCATION MAPS FOR EXPECTED BEDROCK REMOVAL WITHIN PROJECT AREA

Expand Pond 1B Estimated Excavation in Bedrock Depth = 8 ft Estimated Excavation in Bedrock Volume = 220 cu yd

SH45 Ponds SH 45

Lakecreek Vaults (Underground)

RM 620

LegendPECAN PARK

Existing BMPs

Flow Direction Drainage Area "A" Drainage Divide Outfall Crossings Karst Zone 1 Potential Critical Salamander Habitat Edwards Aquifer Recharge Zone Proposed Sidewalk Proposed Pavement per Drainage Area A B

C LAKE CREEK D E F G H

0250 500 1,000 183N Feet ¯ Drainage Area "A" Cont'd 1 in = 500 ft LAKE CREEK

Expand Ponds 2A and 2B Estimated Excavation in Bedrock Depth = 15 ft Estimated Excavation in Bedrock Volume = 826 cu yd

Hymeadow Vaults (Underground)

MELLOW MEADOW

Drainage Area "B" COPPER CREEK

HYMEADOW Pond Springs Pond

HIDDEN MEADOW POND SPRINGS

WOODLAND VILLAGE SHADY OAKS

WOOD IBIS CALDWELL

Drainage Area "C" EDDYSTONE

Expand WQ pond CALDWELL Estimated Excavation in Bedrock Depth = 9 ft

LOIS Estimated Excavation in Bedrock Volume = 1,411 cu yd

Legend

Existing BMPs ANDERSON MILL Flow Direction Drainage Divide Outfall Crossings Karst Zone 1 Potential Critical Salamander Habitat Edwards Aquifer Recharge Zone Proposed Sidewalk Proposed Pavement per Drainage Area A B C D E F G H

0250 500 1,000 183N Feet ¯ Drainage Areas "B" and "C" 1 in = 500 ft POND SPRINGS

ANDERSON MILL

Expand wet pond Estimated Excavation in Bedrock Depth = 12 ft Estimated Excavation in Bedrock Volume = 3,528 cu yd

BALCONES CLUB Woods Pond

BOARDWALK

BROOKWOOD ROXIE

Drainage Area "D"

HUNTERS CHASE

Legend

Existing BMPs OCEANAIRE Flow Direction BALCONES CLUB Drainage Divide

Outfall Crossings Drainage Area "E" Karst Zone 1 Potential Critical Salamander Habitat Edwards Aquifer Recharge Zone Proposed Sidewalk

Proposed Pavement per Drainage Area FATHOM CREST RIDGE A LEMENS SPICE

B FOUR IRON C D E F G H

0250 500 1,000 183N Feet ¯ Drainage Area "D" 1 in = 500 ft WQ Volume needed to reach 85% treatment (including treatment of some existing lanes) = 28377 cuft

E HUNTERS CHAS Install biofiltration swales along north median of 183N (1ft depth)

Estimated maximumPOND SP available WQ volume = 18,500 cuft Estimated Excavation in Bedrock Depth= 2 ft Estimated ExcavationRINGS in Bedrock Volume = 500 cu yd

LCONES E R AI

EAN C CL O UB Install water quality pond

Estimated WQ Volume = 9334 cuft SAN FELIPE Area = 4667 sqft WQ Depth = 2 ft Install water quality pond under bridge Estimated Excavation in Bedrock Depth= 0 ft Estimated WQ Volume = 28,400 cuft Estimated Excavation in Bedrock Volume = 0 cu yd Area = 14,200 sqft WQ Depth = 2 ft Rattan Creek Estimated Excavation in Bedrock Depth= 0 ft F A THO Estimated Excavation in Bedrock Volume = 0 cu yd M CREST RIDGE

SAN F

LEMENS SPI

E F Drainage Area "E" OUR MC NEIL

IRON

J E K E L

P E C

A N

NGS

CEWOOD SPRI SPI

NGTON Legend RI P ARLIAME BAR JOLLYVI Existing BMPs Proposed Pavement LLE YARD NT D DUNDEE Flow Direction Drainage Area "A" OW

NIN OTLAND CHARING SC Drainage Divide Drainage Area "B" G C Outfall Crossings Drainage Area "C" ROSS Shared Use Path Drainage Area "D" Proposed Sidewalk Drainage Area "E" 0250 500 1,000 Drainage Area "F" 183N Feet Drainage Area "G" ¯ Drainage Area "E" Drainage Area "H" 1 in = 500 ft PECAN

JOLLYVILLE JEKEL

DUNDEE

TECHNOLOGY

CHARING CROSS

COMMONWEALTH

CHELSEA MOOR

ATTAR ARGONNE FOREST

BURLINGTON Drainage Area "F" WINEDALE

SCRUB OAK

RIATA TRACE

DOUBLOON

ARGONNE FOREST OAK KNOLL

BROAD OAKS

COLUMBIA OAKS

JOLLYVILLE TWEED CONRAD

BELL

THREE OAKS PAVILION Legend

Existing BMPs Proposed Pavement per Drainage Area Flow Direction A ARABIAN Drainage Divide B Outfall Crossings C HAMRICH Karst Zone 1 D Potential Critical Salamander Habitat E 0250 500 1,000 Edwards Aquifer Recharge Zone F Feet 183N Proposed Sidewalk G ¯ Drainage Area "F" H 1 in = 500 ft RIATA TRACE

PAVILION

TWEED CONRAD

BELL

ARABIAN

HAMRICH

BELL

HIGHLAND OAKS

SECREST

RAIN FOREST

STANWOOD West Cow Path Pond

WEST COW Drainage Area "F"

DUVAL

JOLLYVILLE

THUNDER CREEK Expand WQ pond

Estimated Excavation in Bedrock Depth = 12 ft ANGUS

EstimatedTHUNDER Excavation CREEK in Bedrock Volume = 8,197 cu yd

Legend

Existing BMPs Flow Direction Drainage Divide NATRONA Outfall Crossings ELK PARK Karst Zone 1 WIND RIVER Potential Critical Salamander Habitat Edwards Aquifer Recharge Zone Proposed Sidewalk Proposed Pavement per Drainage Area A

B FAST HORSE C D E F G

H TAYLOR DRAPER

0250 500 1,000 183N Feet ¯ Drainage Area "F" Cont'd 1 in = 500 ft ANGUS WIND RIVERNATRONA

ELK PARK

FAST HORSE

TAYLOR DRAPER

Expand WQ pond GERONA Estimated Excavation in Bedrock Depth = 20 ft Estimated Excavation in Bedrock Volume = 9,614 cu yd

BALCONES WOODS TOLEDO FLORAL PARK

SANTA CRUZ Seton Pond

Drainage Area "G"

MORADO

SETON CENTER

HAMILTON

JOLLYVILLE Legend BRAKER Existing BMPs MORADO Flow Direction Drainage Divide BRAKER Outfall Crossings Karst Zone 1 Potential Critical Salamander Habitat Edwards Aquifer Recharge Zone Proposed Sidewalk Proposed Pavement per Drainage Area A B STONELAKE

C CELETA D E F G

STONELAKE H

0250 500 1,000 183N Feet ¯ Drainage Area "G" 1 in = 500 ft STONELAKE JOLLYVILLE

GREAT HILLS

ARBORETUM

Drainage Area "G"

CAPITAL OF TEXAS

YORK

JOLLYVILLE

ROCKCREST

STONELAKE

Install WQ pond Estimated Excavation in Bedrock Depth = 6 ft

Estimated Excavation in Bedrock Volume = 2,900 cuTUDOR yd

DOMINION

Legend

Existing BMPs Flow Direction MESA Drainage Divide Drainage Area "H" Outfall Crossings SILVERARROW Karst Zone 1 Potential Critical Salamander Habitat Edwards Aquifer Recharge Zone Proposed Sidewalk Proposed Pavement per Drainage Area

A SILVERHILL SILVERSPRING B C D

E BUSINESS PARK

F HONEYSUCKLE G TALLWOOD H

0250 500 1,000 183N Feet ¯ Drainage Areas "G" Cont'd and "H" 1 in = 500 ft