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LSA ASSOCIATES, INC. FRESNO RIVERSIDE 20 EXECUTIVE PARK, SUITE 200 949.553.0666 TEL BERKELEY PALM SPRINGS ROCKLIN IRVINE, CALIFORNIA 92614 949.553.8076 FAX CARLSBAD PT. RICHMOND SAN LUIS OBISPO

MEMORANDUM

DATE: July 11, 2016

TO: Nicole Dubois

FROM: Sarah Rieboldt, Ph.D.

SUBJECT: Paleontological Analysis of the Del Obispo Street Widening Project, City of San Juan Capistrano, County of Orange, California

INTRODUCTION The City of San Juan Capistrano (City) proposes the Del Obispo Street Widening Project (project) to eliminate the existing traffic bottle-neck on the west side of Del Obispo Street from Calle Aspero to Paseo De La Paz. The project site is depicted on the United States Geological Survey (USGS) Dana Point, California 7.5-minute topographic quadrangle map in Township 8 South, Range 8 West, Sections 11 and 12 (USGS, 1981; Figure 1) .

Development of this project involves widening two sections of Del Obispo Street to provide two southbound lanes where there is currently one lane. A portion of Del Obispo Street was previously widened as a part of the Oliva Development Tentative Tract Map 16146, but it is currently stripped out and is unavailable for traffic. The project will add a second southbound lane along 770 feet (ft) of the roadway from Calle Aspero to the north end of the Oliva Development and along 400 ft of the roadway from the south end of the Oliva Development to Paseo De La Paz. A minimum of 10 ft of widening will be required on the west side of Del Obispo Street. The east side of Del Obispo Street, between Calle Aspero and Paseo De La Paz is already widened to its ultimate width. Other project improvements include a new sidewalk on the west side of the street, new bikes lanes in each direction, and new street lights.

This memorandum was prepared to ensure project compliance with all applicable State and City regulations and guidelines regarding paleontological resources, including the California Environmental Quality Act (CEQA): Public Resources Code (PRC) Division 13, Chapter 2.6; the State CEQA Guidelines: California Code of Regulations (CCR), Title 14, Chapter 3, Appendix G; PRC 5097.5; City Council Policy Number 601; and the Society of Vertebrate Paleontology (SVP, 2010). It addresses the potential for the project to adversely impact paleontological resources and, as needed, includes mitigation measures and other recommendations to minimize these impacts.

Methods LSA Associates, Inc. (LSA) examined geologic maps of the project site and reviewed relevant geological and paleontological literature to determine which geologic units are present within the project site and whether fossils have been recovered within the project site or from those or similar geologic units elsewhere in the region. A search for known fossil localities was also conducted

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San Diego County

LEGEND FIGURE 1 Project Location

0 1000 2000 Del Obispo Street Widening FEET Project Location Map SOURCE: USGS 7.5' Quad - Dana Point (1975), CA I:\CNF1501\GIS\ProjectLocation_USGS.mxd (1/6/2016) LSA ASSOCIATES, INC.

through the Natural History Museum of Los Angeles County (LACM) in order to determine the status and extent of previously recorded paleontological resources within and surrounding the project site. A pedestrian field survey of the project site was conducted by LSA Associate Roderic McLean on June 15, 2016. This survey involved walking along the roadway and in linear transects over the larger areas along Del Obispo Street to observe the surface deposits and to document and collect any paleontological resources that may have been present. Areas that were paved were not surveyed.

RESULTS Literature Review The project is located at the northern end of the Peninsular Ranges Geomorphic Province, a 900-mile (mi) long northwest-southeast-trending structural block that extends from the Transverse Ranges in the north to the tip of Baja California in the south and includes the Los Angeles Basin (California Geological Survey, 2002; Norris and Webb, 1976). This province is characterized by mountains and valleys that trend in a northwest-southeast direction, roughly parallel to the San Andreas Fault. The total width of the province is approximately 225 mi, extending from the Colorado Desert in the east, across the continental shelf, to the Southern Channel Islands (i.e., Santa Barbara, San Nicolas, Santa Catalina, and San Clemente) (Sharp, 1976). It contains extensive pre-Cretaceous (more than 145 million years ago [Ma]) and Cretaceous (145 to 66 Ma) igneous and metamorphic rock covered by limited exposures of post-Cretaceous (less than 66 Ma) sedimentary deposits (Norris and Webb, 1976).

Within this larger region, the project is located in the Los Angeles Basin, a broad alluvial lowland bounded to the north and east by the San Gabriel and Santa Ana Mountains, respectively, and by the Pacific Ocean to the southwest (Yerkes et al., 1965). The basin is underlain by a structural depression that has discontinuously accumulated thousands of feet of marine and terrestrial deposits since the Late Cretaceous (approximately 100.5 Ma) (Yerkes et al., 1965). Over millions of years, the basin has experienced episodes of subsidence, deposition, uplift, erosion, and faulting, all of which have resulted in very complex geology (Yerkes et al., 1965). The surface of the basin slopes gently southwestward toward the ocean, interrupted in various places by low hills and traversed by several large rivers (Sharp, 1976; Yerkes et al., 1965), including the Los Angeles River, the Rio Hondo, the San Gabriel River, and the Santa Ana River.

Geologic mapping by Kennedy and Tan (2007) and Tan (1999) shows that the project site contains Younger Alluvial Flood Plain Deposits, Younger Alluvial Fan Deposits, Older Alluvial Flood Plain Deposits, and the Capistrano Formation. In addition, the project site likely contains Artificial Fill placed during construction of Del Obispo Street. The geology of the project site is shown in Figure 2, and these geologic units are discussed in more detail below.

7/11/16 «P:\CNF1501\Technical Studies_Sections\Paleo\Del Obispo Widening Paleontology Memo.docx» 3 LEGEND FIGUR2 E ProjectLocation Geology

QyaYoungeras– Alluvial Flood Plain Deposits

QyfYoungeras– Alluvial DepositsFan

QoaOldga– erAlluvial River Deposits 0 175 350 Del Obispo Street Widening FEET Capistrano –Tcs Form ation GeologyMap SOURAerial CE:Bing Geology Maps - Tan(1999). (2014); - sandy as- silt with som clay e gravelly - gsand with clayandsilt I:\CNF1501\GIS\Geology.mx d(1/14/2016) LSA ASSOCIATES, INC.

Artificial Fill. Artificial Fill consists of sediments that have been removed from one location and transported to another location by human activity, rather than by natural means. The transportation distance can vary from a few feet to many miles, and composition is dependent on the source and purpose. Artificial Fill will sometimes contain modern debris such as asphalt, wood, bricks, concrete, metal, glass, plastic, and even plant material. Some amount of Artificial Fill likely underlies the existing roadways and intersections within the project site.

While Artificial Fill may contain fossils, these fossils have been removed from their original location and are thus out of stratigraphic context. Therefore, they are not considered important for scientific study. As such, Artificial Fill has no paleontological sensitivity.

Younger Alluvial Flood Plain Deposits and Younger Alluvial Fan Deposits. The Younger Alluvial Flood Plain Deposits and Younger Alluvial Fan Deposits are Holocene to Late Pleistocene in age (less than 126,000 years ago) and consist of poorly consolidated and poorly sorted mixtures of sand, silt, and clay (Kennedy and Tan, 2007; Tan, 1999). The Younger Alluvial Flood Plain Deposits are generally found adjacent to stream and river channels and represent deposition during flood events. These deposits are mapped throughout the project site. The Younger Alluvial Fan Deposits accumulated as sediment eroded from higher elevations and was deposited in a fan or lobe shape at the base of the hills. These deposits are mapped in the northern and central portions of the project site.

Although the younger Holocene (less than 11,700 years ago) sediments within these geologic units may contain remains of plants and animals, generally not enough time has passed for them to become fossilized. In addition, these remains would be conspecific with modern species, and therefore, usually are not considered scientifically significant. However, scientifically significant fossils are known from the older, late Pleistocene (11,700–126,000 years ago) sediments within this geologic unit elsewhere in Southern California (Jefferson, 1991a, 1991b; Miller, 1971; Reynolds and Reynolds, 1991; Springer et al., 2009). These older deposits span the end of the Rancholabrean North American Land Mammal Age (NALMA), which was named for the Rancho La Brea fossil site in central Los Angeles and dates from 11,000 to 240,000 years ago (Alroy, 2000). The presence of Bison defines the beginning of the Rancholabrean NALMA (Bell et al., 2004), but fossils from this time also include other large and small mammals, reptiles, fish, invertebrates, and plants. There is a potential to encounter these types of fossils in the older sediments of these geologic units in the project site below a depth of approximately 10 ft. Therefore, the Younger Alluvial Flood Plain Deposits and Younger Alluvial Fan Deposits are considered to have low paleontological sensitivity from the surface to a depth of 10 ft and high sensitivity below that mark.

Older Alluvial Flood Plain Deposits. The Older Alluvial Flood Plain Deposits are late to middle Pleistocene in age (11,700–781,000 years ago). They are composed of moderately consolidated, mixtures of gravel, sand, silt, and clay (Kennedy and Tan, 2007; Tan, 1999). These deposits are generally found adjacent to stream and river channels and represent deposition during flood events. They are mapped in a small portion of the project site at the south end of Del Obispo Street.

These deposits span the latest two NALMAs: the Rancholabrean and the Irvingtonian (240,000–1.8 Ma) (Alroy, 2000). Fossils have been recovered from similar Rancholabrean and Irvingtonian deposits during excavations for roads, housing developments, and quarries, as well as scientific investigations within Southern California (Jefferson, 1991a, 1991b; Miller, 1971; Pajak et al., 1996;

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Reynolds and Reynolds, 1991; Springer et al., 2009). These fossils include mammoths, mastodons, horses, bison, camels, saber-toothed cats, coyotes, deer, and sloths, as well as smaller animals like rodents, rabbits, birds, reptiles, and fish. As such, these deposits are considered to have high paleontological sensitivity.

Capistrano Formation. The marine Capistrano Formation was deposited during the early Pliocene to late Miocene (3.6–11.62 Ma) (Kennedy and Tan, 2007; Tan, 1999). It has two facies, which are distinguished by their depositional environments and corresponding compositions. The turbidite facies formed in marine channel and sub-sea fan environments; it is composed of coarse-grained, poorly bedded, weakly cemented sandstone and conglomeratic sandstone (Kennedy and Tan, 2007; Tan, 1999). In contrast, the siltstone facies accumulated in deep shelf and slope environments and consists of white to pale gray, massive to poorly bedded, friable siltstone, mudstone, and diatomaceous shale (Kennedy and Tan, 2007; Tan, 1999). The siltstone facies is mapped in a small portion of the project site at the northern end of Del Obispo Street.

This formation has produced abundant and diverse scientifically significant fossils, many of which come from the siltstone facies. These fossils include bony fish, sharks, whales, porpoises, sea lions, sea cows, and marine birds (Barnes and Raschke, 1991; Démeré and Berta, 2005; Ebeling, 1962; Eisentraut and Cooper, 2002; Smith, 2011). As such, these deposits are considered to have high paleontological sensitivity.

Fossil Locality Search According to the locality search conducted by the LACM, there are no known fossil localities within the boundaries of the project. The LACM reports that the project site is underlain by deposits of younger Quaternary flood plain deposits (i.e., Young Alluvial Flood Plain Deposits and Younger Alluvial Fan Deposits), older Quaternary non-marine terrace deposits (i.e., Older Alluvial Flood Plain Deposits), and a small area of the Capistrano Formation. The younger Quaternary flood plain deposits typically do not contain scientifically significant vertebrate fossils, at least in the uppermost layers, but may overlie older Quaternary sediments that may contain important fossils. The museum has fossil localities nearby from older Quaternary deposits, the closest of which is LACM 2028, located directly south of the project site at Doheny Beach State Park. This locality produced a fossil specimen of bison (Bison). The museum has many fossil localities near the project site from the Capistrano Formation, the closest of which are LACM 5792 and 5889, located northeast of the project site, north of San Juan Creek and east of Interstate 5. These localities yielded an extensive marine fauna, including requiem sharks (Carcharhinus obscurus, Hemipristis serra), cow sharks (Hexanchus), mackerel sharks (Carcharocles megalodon, Carcharodon carcharias, Isurus hastalis, I. oxyrhinus, I. planus, Lamna), eagle rays (Myliobatis), wrasses (Semicossyphus pulcher), cormorants (Phalacrocoracidae), grebes (Podiceps parvus), sea lions (Otariinae), right whales (Balaenidae), rorqual whales (Balaenopteridae), primitive baleen whales (Cetotheriidae), dolphins (Stenella), porpoises (Phocoenidae), sperm whales (Scaldicetus), “river” dolphins (Parapontoporia), and sea cows (Dugongidae), as well as terrestrial and freshwater animals, including elephants (Proboscidea), camels (Camelidae), pronghorn antelopes (Antilocapridae), and western pond turtles (Emys marmorata). From the cliffs above the beaches around Dana Point, south of the project site, the museum also has the following localities in the Capistrano Formation: LACM 1875, 1950, 4012, 4347, 6474, 6595, 6991–6992, and 7296. These localities produced abundant marine vertebrates,

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including bonito shark (Isurus), white shark (Carcharodon carcharias), herring (Xyne grex), cod (Eclipes), snake mackerel (Thyrsocles), deep-sea smelt (Bathylagidae), rockfish (Scopaenidae), bristlemouth (Cyclothone), pipefish (Syngnathus), extinct leatherback sea turtle (Psephophorus), crocodile (Crocodilia), shearwater (Puffinus diatomicus), sea lion (Pontolis magnus), sea cow (Dugongidae), and whale (Cetacea). The museum notes that the extinct leatherback sea turtle is an uncommon fossil, and the crocodile is very rare for California, making these fossils scientifically very important.

The LACM believes that shallow excavations in the younger Quaternary alluvial deposits in the project site are unlikely to recover any scientifically important vertebrate fossils. However, deeper excavations, or excavations into the older Quaternary alluvial deposits or the Capistrano Formation, may encounter scientifically significant vertebrate remains and should be monitored to recover those remains. The results letter from the LACM is provided in Attachment A.

Field Survey The pedestrian survey indicated that the project site was highly disturbed and much of the site was covered with non-native vegetation. Where visible, the sediments appeared to be consistent with the geologic units mapped in that area by Morton and Miller (2006). No paleontological resources were encountered during the survey.

RECOMMENDATIONS Although no scientifically significant paleontological resources were identified directly within the project site during the locality search or field survey, the results of the locality search and literature review indicate that the project site encompasses deposits of high paleontological sensitivity. These deposits include the older sediments below a depth of 10 ft in the Holocene to late Pleistocene Younger Alluvial Flood Plain Deposits and Younger Alluvial Fan Deposits, as well as the middle to early Pleistocene Older Alluvial Flood Plain Deposits and the Capistrano Formation. Therefore, there is a potential to encounter scientifically significant paleontological resources during ground- disturbing activities in the project site. In order to mitigate potential adverse impacts to scientifically significant, nonrenewable paleontological resources, as required by CEQA Appendix G, PRC Section 5097.5, and the City Council policy, LSA recommends the following mitigation measure:

PALEO-1 A paleontologist shall be hired to develop a Paleontological Resource Impact Mitigation Program (PRIMP) for this project. The PRIMP shall include the methods that will be used to protect paleontological resources that may exist within the project site, as well as procedures for monitoring, fossil preparation and identification, curation into a repository, and preparation of a report at the conclusion of grading.

 Excavation and grading activities in deposits with a high paleontological sensitivity rating (Younger Alluvial Flood Plain Deposits or Younger Alluvial Fan Deposits below a depth of 10 ft from the surface, Older Alluvial Flood Plain Deposits, or the Capistrano Formation) shall be monitored by a qualified paleontologist following a PRIMP. If fossils are recovered from sediments with low paleontological sensitivity (Younger Alluvial Flood Plain Deposits and Younger Alluvial Fan Deposits from the surface to a depth of 10 ft), the

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paleontologist shall make recommendations as to whether monitoring shall be required in these sediments on a full-time basis beginning at a shallower depth.  In the event that paleontological resources are encountered when a paleontological monitor is not present, work in the immediate area of the find shall be redirected and a paleontologist shall be contacted to assess the find for significance. If determined to be significant, the fossil shall be collected from the field.  If paleontological resources are encountered during the course of ground disturbance, the paleontological monitor shall have the authority to temporarily redirect construction away from the area of the find in order to assess its significance.  Collected resources shall be prepared to the point of identification, identified to the lowest taxonomic level possible, cataloged, and curated into the permanent collections of an accredited scientific institution.  At the conclusion of the monitoring program, a report of findings shall be prepared to document the results of the monitoring program.

REFERENCES Alroy, John 2000 New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707–733.

Barnes, Lawrence G., and Rodney E. Raschke 1991 Gomphotaria pugnax, a New Genus and Species of Late Miocene Dusignathine Otariid Pinniped (Mammalia: Carnivora) from California. Natural History Museum of Los Angeles County Contributions in Science 426:1-16.

Bell, Christopher J., Ernest L. Lundelius, Jr., Anthony D. Barnosky, Russell W. Graham, Everett H. Lindsay, Dennis R. Ruez, Jr., Holmes A Semken, Jr., S. David Webb, and Richard J. Zakrzewski 2004 The Blancan, Irvingtonian, and Rancholabrean Mammal Ages. Chapter 7 in Michael O. Woodburne, ed., Late Cretaceous and Cenozoic Mammals of North America. pp. 232–314.

California Geological Survey 2002 California Geomorphic Provinces. California Geologic Survey Note 36. California Department of Conservation.

Démeré, Thomas A., and Annalisa Berta 2005 New skeletal material of Thalassoleon (Otariidae: Pinnipedia) from the Late Miocene- Early Pliocene (Hemphillian) of California. Bulletin of the Florida Museum of Natural History 45(4):379-411.

Ebeling, Alfred W. 1962 Scopelogadus (?) capistranensis, a New Fossil Melamphaid (Pisces: Teleostei) from Capistrano Beach, California. Postilla, Yale Peabody Museum of Natural History 71:1–6.

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Eisentraut, P., and J. Cooper 2002 Development of a Model Curation Program for Orange County’s Archaeological and Paleontological Collections. Prepared by California State University, Fullerton and submitted to the County of Orange Public Facilities Resources Department/Orange County Harbors, Beaches, and Parks (PFRD/HBP).

Jefferson, George T. 1991a A Catalogue of Late Quaternary Vertebrates from California: Part One: Non-marine Lower Vertebrate and Avian Taxa. Natural History Museum of Los Angeles County Technical Reports Number 5, Los Angeles.

1991b A Catalogue of Late Quaternary Vertebrates from California: Part Two: Mammals. Natural History Museum of Los Angeles County Technical Reports Number 7, Los Angeles.

Kennedy, Michael P., and Siang S. Tan 2007 Geologic Map of the Oceanside 30’ x 60’ Quadrangle, California. Digital Preparation by Kelly R. Bovard, Rachel M. Alvarez, and Michael J. Watson. Prepared by the California Geological Survey in cooperation with the United States Geological Survey, Southern California Areal Mapping Project. Regional Geologic Map Series, Map #2. Map Scale 1:100,000.

Morton, Douglas M., and Fred K. Miller 2006 Geologic Map of the San Bernardino and Santa Ana 30-minute by 60-minute quadrangles, California. Digital preparation by Pamela M. Cosette and Kelly R. Bovard. Prepared by the United States Geological Survey (USGS) in cooperation with the California Geological Survey. USGS Open File Report 2006-1217. Map Scale 1:100,000.

Miller, W.E. 1971 Pleistocene Vertebrates of the Los Angeles Basin and Vicinity (Exclusive of Rancho La Brea). Los Angeles County Museum of Natural History Bulletin, Science: No. 10.

Norris, R.M., and R.W. Webb 1976 Geology of California. New York: John Wiley and Sons, Inc. 379 pp.

Pajak, Alois F., Jr., Eric Scott, and Christopher J. Bell 1996 A Review of the Biostratigraphy of Pliocene and Pleistocene Sediments in the Elsinore Fault Zone, Riverside County, California. PaleoBios 17(2-4):28-49.

Reynolds, R.E., and R.L. Reynolds 1991 The Pleistocene Beneath our Feet: Near-surface Pleistocene Fossils in Inland Southern California Basins. In M.O. Woodburne, R.E. Reynolds, and D.P. Whistler, eds., Inland Southern California: The Last 70 Million Years, Redlands, San Bernardino County Museum Special Publication 38(3 and 4): 41–43.

Sharp, R.P. 1976 Geology: Field Guide to Southern California, Kendall/Hunt Publishing Company, Second Edition: 181.

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Smith, N. Adam 2011 Taxonomic Revision and Phylogenetic Analysis of the Flightless Mancallinae (Aves, Pan- Alcidae). ZooKeys 91:1–116.

Society of Vertebrate Paleontology (SVP) 2010 Standard Procedures for the Assessment and Mitigation of Adverse Impacts to Paleontological Resources. Society of Vertebrate Paleontology. Impact Mitigation Guidelines Revision Committee. 11 pp.

Springer, Kathleen, Eric Scott, J. Christopher Sagebiel, and Lyndon K. Murray 2009 The Diamond Valley Lake Local Fauna: Late Pleistocene Vertebrates from Inland Southern California. In L.B. Albright, III, ed. Papers in Geology, Vertebrate Paleontology, and Biostratigraphy in Honor of Michael O. Woodburne, Museum of Northern Arizona Bulletin 65, pp. 217–236.

Tan, Siang S. 1999 Geologic Map of the Dana Point 7.5’ Quadrangle, Orange County, California: A Digital Database Version 1.0. Digital Database by Gary W. Patt and Kelly R. Ruppert. Prepared by the California Department of Conservation Division of Mines and Geology in cooperation with the United States Geological Survey, Southern California Areal Mapping Project. Map Scale 1:24,000.

United States Geological Survey (USGS) 1981 Dana Point, California 7.5-minute topographic quadrangle. Published 1968, photorevised 1975. United States Geological Survey, Denver, Colorado.

Yerkes R.F., T.H. McCulloh, J.E. Schoellhamer, and J.G. Vedder 1965 Geology of the Los Angeles Basin California – an Introduction, U.S. Geologic Survey Professional Paper 420-A, 57 pp.

ATTACHMENT Paleontological Locality Search Results from the Natural History Museum of Los Angeles County

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ATTACHMENT A

PALEONTOLOGICAL LOCALITY SEARCH RESULTS FROM THE NATURAL HISTORY MUSEUM OF LOS ANGELES COUNTY

P:\CNF1501\Technical Studies_Sections\Paleo\Del Obispo Widening Paleontology Memo.docx «07/11/16» Vertebrate Paleontology Section Telephone: (213) 763-3325 Fax: (213) 746-7431 e-mail: [email protected]

20 January 2016 LSA Associates, Inc. 20 Executive Park, Suite 200 Irvine, California 92614

Attn: Sarah Rieboldt, Ph.D., Paleontologist re: Paleontological Resources Records Check for the proposed Del Obispo Street Widening Project, LSA Project # CNF1501, in the City of San Juan Capistrano, Orange County, project area

Dear Sarah:

I have thoroughly searched our paleontology collection records for the locality and specimen data for the proposed Del Obispo Street Widening Project, LSA Project # CNF1501, in the City of San Juan Capistrano, Orange County, project area as outlined on the portion of the Dana Point USGS topographic quadrangle map that you sent to me via e-mail on 6 January 2016. We do not have any vertebrate fossil localities that lie directly within the proposed project boundaries, but we do have localities nearby from the same sedimentary deposits that occur in the proposed project area, either on the surface or at depth.

The surface sediments on the eastern side of the proposed project area consist of younger Quaternary flood plain deposits from the Trabuco Creek and San Juan Creek that flow just to the east. These deposits typically do not contain significant vertebrate fossils in the uppermost layers and we have no localities nearby from these deposits, but older fossiliferous deposits may be found at relatively shallow depth in this area. On the western side of the proposed project area there are older Quaternary non-marine terrace deposits. Our closest vertebrate fossil locality that may have been derived from similar terrace deposits is LACM 2028, located directly south of the proposed project area at Doheny State Beach, that produced a fossil specimen of bison, Bison. According to the geologic mapping there are some small exposures of the marine late Miocene Capistrano Formation either within or along the proposed project area. The surrounding hills also have bedrock exposures of the Capistrano Formation and it probably occurs at depth in the rest of the proposed project area. Our closest vertebrate fossil localities from the Capistrano Formation are LACM 5792 & 5889, situated northeast of the proposed project area north of San Juan Creek and east of the San Diego Freeway (I-5). These localities produced an extensive fossil marine fauna, particularly at locality LACM 5792 (see faunal list in attached appendix), primarily of marine vertebrates such as sharks, bony fishes, marine birds, sea lions, whales, and sea cows, but also including some terrestrial and freshwater specimens, including elephants and pond turtles. We also have several vertebrate fossil localities from the Capistrano Formation south of the proposed project area in the cliff exposures above the beaches from just east of Dana Point southwards towards San Clemente, including LACM 1875, 1950, 4012, 4347, 6474, 6595, 6991-6992, and 7296. These localities also produced a suite of fossil marine vertebrates including bonito shark, Isurus, white shark, Carcharodon carcharias, herring, Xyne grex, cod, Eclipes, snake mackerel, Thyrsocles, deep-sea smelt, Bathylagidae, rockfish, Scorpaenidae, bristlemouth, Cyclothone, pipefish, Syngnathus, leatherback turtle, Psephophorus, crocodile, Crocodilia, shearwater, Puffinus diatomicus, sea lion, Pontolis magnus, sea cow, Dugongidae, and whale, Cetacea. The leatherback turtle, Psephophorus, is an uncommon fossil and the crocodile, Crocodilia, specimen is quite rare for California. The sea lion, Pontolis magnus, specimen was published in the scientific literature by E.D. Mitchell in 1968 (The Mio-Pliocene pinniped Imagotaria. Journal of the Fisheries Research Board of Canada, 25(9):1843-1900) and also by L.G. Barnes & R.E. Raschke in 1991(Gomphotaria pugnax, a new genus and species of Late Miocene dusignathine otariid pinniped (Mammalia: Carnivora) from California. Contributions in Science, Natural History Museum of Los Angeles County, 426:1-16.).

Shallow excavations in the younger Quaternary Alluvium exposed on the eastern side of the proposed project area and very shallow excavations in the older Quaternary terrace deposits exposed on the western side of the proposed project area may not uncover any significant vertebrate fossils. Deeper excavations in those areas that extend down into the older sedimentary deposits, as well as any excavations in the Capistrano Formation exposures, however, may well encounter significant vertebrate fossils. Any substantial excavations in the proposed project area, therefore, should be closely monitored to quickly and professionally collect any specimens without impeding development. Sediment samples should also be collected and processed to determine the small fossil potential in the proposed project area. Any fossils recovered during mitigation should be deposited in an accredited and permanent scientific institution for the benefit of current and future generations.

This records search covers only the vertebrate paleontology records of the Natural History Museum of Los Angeles County. It is not intended to be a thorough paleontological survey of the proposed project area covering other institutional records, a literature survey, or any potential on-site survey.

Sincerely,

Samuel A. McLeod, Ph.D. Vertebrate Paleontology enclosures: appendix; invoice Fossil fauna from the Capistrano Formation at locality LACM 5792

Chondrichthyes Carcharhiniformes Carcharhinidae - requiem sharks Carcharhinus obscurus Hemipristis serra Hexanchiformes Hexanchidae - cow sharks Hexanchus Lamniformes Lamnidae - mackerel sharks Carcharocles megalodon Carcharodon carcharias Isurus hastalis Isurus oxyrinchus Isurus planus Lamna Myliobatiformes Myliobatidae - eagle rays Myliobatis Osteichthyes Perciformes Labridae - wrasses Semicossyphus pulcher Reptilia Chelonia Emydidae - pond turtles Clemmys marmorata Aves Pelecaniformes Phalacrocoracidae - cormorants Podicipediformes Podicipedidae - grebes Podiceps parvus Mammalia Artiodactyla Antilocapridae - pronghorn antelopes Camelidae - camels Carnivora Otariidae - sea lions & walruses Odobeninae Otariinae Cetacea Balaenidae - right whales Balaenopteridae - rorqual whales Cetotheriidae - primitive baleen whales Delphinidae - dolphins Stenella Phocoenidae - porpoises Physeteridae - sperm whales Scaldicetus Pontoporiidae - “river” dolphins Parapontoporia Proboscidea - elephants Sirenia Dugongidae - sea cows 5 Project Vicinity ¨¦§ Ã261 ¨¦§15 Ã55 133 Ã Ã241 405 ¨¦§ Orange Ã73 County