TWISSELMAN QUARRY EXPANSION AREA BIOLOGICAL RESOURCES SUMMARY

Document Sample
TWISSELMAN QUARRY EXPANSION AREA BIOLOGICAL RESOURCES SUMMARY Powered By Docstoc
					     




                                          

 
 
                                          




                   TWISSELMAN QUARRY EXPANSION AREA
                    BIOLOGICAL RESOURCES SUMMARY


                                   Prepared by:

                            H. T. Harvey & Associates
                          7815 N. Palm Avenue, Suite 310
                                Fresno, CA 93711




                                   Prepared for:

                           SunPower CA Solar Ranch
                                P.O. Box 3821
                           Sunnyvale, CA 94088-3821




        8 April 2010                                       File No. 3103-01
                                          
                        CALIFORNIA VALLEY SOLAR RANCH PROJECT
              TWISSELMAN QUARRY BIOLOGICAL RESOURCES SUMMARY

               TWISSELMAN QUARRY EXPANSION AREA
                BIOLOGICAL RESOURCES SUMMARY

A gypsum/aggregate quarry north of the proposed CVSR switch station, referred to as the
“Twisselman Quarry”, will be mined for raw building materials that will be used by the
CVSR Project. This quarry currently serves, and will continue to serve, multiple users in
addition to the CVSR, and expansion of the quarry is proposed to meet the demands of
these users. While the transportation of materials from the quarry to the CVSR project is
a component of the proposed action for the larger CVSR project, quarry expansion and
operation is covered under a separate Section 7 consultation because the quarry has
served, and will continue to serve, multiple users in addition to the CVSR.

The biological resources present in and around the Twisselman Quarry were generally
described in the Revised Biological Resources Assessment Report for the California
Valley Solar Ranch Project, San Luis Obispo County, California. However, the level of
detail regarding biological resources at the quarry itself varied among resources.
Therefore, this report briefly summarizes the existing habitat conditions at the quarry, the
known and potential occurrence of special-status species and sensitive/regulated habitats
at the quarry site, and potential impacts to those biological resources. For detail on the
species composition of habitats, natural histories of special-status species, and occurrence
of special-status species in the region and on the larger CVSR Project site, please refer to
the Revised Biological Resources Assessment Report for the California Valley Solar
Ranch Project, San Luis Obispo County, California.

EXISTING HABITAT CONDITIONS / WETLANDS AND OTHER AQUATIC
FEATURES

The Twisselman Quarry expansion area comprises an area of 25.5 acres (Figure 1). Of
this area, 11.5 acres is heavily disturbed by ongoing quarry activities, and is considered
developed. Outside the active quarry footprint, approximately 13.98 acres consists of
annual grassland and 0.02 acres contains ephemeral drainages (shown as “other waters”
on Figure 1).

The Annual Grassland is dominated by the non-native grasses such as rattail fescue
(Vulpia myuros) and red brome (Bromus madritensis ssp. rubens), as well as the non-
native forb, red-stemmed filaree (Erodium cicutarium). Other species present at the site
include mostly native, spring-blooming forbs such as California poppy (Eschscholzia
californica) and alkali parsnip (Lomatium carufolium), as well as stands of native one-
sided blue grass (Poa secunda ssp. secunda). These same species dominate the bed and
banks of the ephemeral drainages.



                                              1-1
                                Legend                                                                              Scale

                                         Twisselman Quarry Survey Boundary (25.5 ac)
                                                                                                                                                                                                               California Valley Solar Ranch
                                                                                                                                                         1:2,400                                             Twisselman Quarry Biological Resources Summary
                                         Twisselman Quarry Disturbed/Developed Area (11.5 ac)
                                                                                                                                               1 inch = 200 feet                                                     Figure 1: Biological Study Area
                                         Twisselman Quarry Annual Grassland Area (14.0 ac)
N:\Projects\3103-01\Report\




                                          Other Waters (0.021 ac)
                                                                                                                       0               100                200                                  400 Feet

                              Data Sources: [1] H.T. Harvey & Associates survey data, [2] USDA NAIP Aerial (2009)   Coordinate System: North American Datum 83 Universal Trans Mecator (UTM) Zone 11 North
                        CALIFORNIA VALLEY SOLAR RANCH PROJECT
              TWISSELMAN QUARRY BIOLOGICAL RESOURCES SUMMARY



These habitats could be lost or degraded though expansion of mine operations, especially
if the footprint of the mine or the roads leading to the mine are expanded. The ephemeral
drainages, especially the drainage on the eastern side of the active mine (Figure 1), could
be filled by expanding mine operations and the placement of aggregate materials in the
drainage beds. Both habitats could also be indirectly impacted by an increase in dust
generated by the mine operations, such as mining, filling of trucks, and driving along the
road, or by erosion of materials draining off the active Quarry site. Such impacts are
expected to be less than significant due to the applicant-proposed measures designed to
protect water quality, and due to the relative abundance of both habitat types in the region
and the immediate area surrounding the mine.

SPECIAL-STATUS PLANTS

The expansion area for the Twisselman Quarry was surveyed for special-status plants by
H. T. Harvey & Associates. These surveys, which were conducted in accordance with
USFWS, CDFG, and CNPS guidelines, and which occurred after a wet season of above-
average rainfall, covered the Quarry site on 18 March and 7 April 2010. No special-
status plants were detected on the Quarry Project site during these surveys, however, an
unknown Eriogonum species was detected before it had produced mature flowers or
fruits, and thus it could not be identified. Therefore, the presence of the CNPS list 1B
species Temblor buckwheat (Eriogonum temblorense) and the CNPS list 4 species
cottony buckwheat (Eriogonum gossypinum), both of which were on the target species
list for the survey, could not be definitively excluded. Based on the results of these
surveys and the habitat present on the Quarry expansion area, it was determined that the
either cottony or Temblor buckwheat could potentially be present, and thus surveys in
May and August 2010 will be conducted to determine presence or absence of those
species.

Potential impacts to special-status plants could include loss or reduction in size of a
population within the Quarry expansion area through loss of habitat caused by expansion
of mine operations and a larger mine footprint. Implementation of mitigation measures
M-BIO 2-7 will reduce or avoid the potential impacts to special-status plants, if present.


INVERTEBRATES

Habitat suitability for special-status vernal pool branchiopods such as the longhorn fairy
shrimp (Branchinecta longiantenna) and vernal pool fairy shrimp (B. lynchi) was assessed
within the Twisselman Quarry expansion area in accordance with USFWS survey
guidelines on March 11 and 12, 2009, by URS senior biologist John H. Davis IV; and

                                              1-3
                        CALIFORNIA VALLEY SOLAR RANCH PROJECT
              TWISSELMAN QUARRY BIOLOGICAL RESOURCES SUMMARY

during a habitat assessment by H. T. Harvey & Associates wetlands/invertebrate
ecologist Kelly Hardwicke, Ph.D. on December 1, 2009.

These habitat assessments identified no features that could potentially support vernal pool
branchiopods, as no pools or ponded areas, nor any depressional areas that could support
suitable conditions, are present on or adjacent to the quarry expansion area. Therefore, these
species are considered absent from the aggregate mine and surrounding areas.

Additionally, during rare plant surveys of the expansion area conducted in March 2010,
H. T. Harvey & Associates botanists searched for suitable host foodplants of the Kern
primrose sphinx moth. The most important habitat component of this species is the
presence of the larval foodplant, which consists of various species of evening primrose
(Camissonia spp.) commonly found in disturbed areas. One individual Mojave suncup
(Camissonia campestris) was found along the very southern boundary of the Quarry
expansion area in April 2010 (in the approximate vicinity of the southern yellow
boundary line shown on Figure 1, more than 50 feet from the road). However, rare plant
surveys conducted in March 2010 revealed no evening primrose plants in the Quarry
expansion area, when evening primrose plants were identifiable in other areas at the same
time. Therefore, the larval foodplant is considered absent from most areas within the
mine site, and no large or dense populations occur within the survey area boundary
shown on Figure 1. Therefore, Kern primrose sphinx moths are not likely to breed in the
Quarry expansion area. Species of plants on which adult moths may feed, including
filaree (Erodium spp.), California goldfields (Lasthenia californica), baby blue-eyes
(Nemophila menziesii), and bicolor lupine (Lupinus bicolor), are widespread throughout
the Carrizo Plain, including the vicinity of the quarry. However, without evening
primrose plants within the quarry expansion area, it is highly unlikely that adult moths
would be present there, and there is no reasonable expectation that quarry activities will
result in any adverse effects on sphinx moths.

REPTILES AND AMPHIBIANS

Amphibians

Visual surveys for amphibians (as well as their larvae and egg masses) in the seasonal
wetlands throughout the CVSR Project site were conducted on March 10-11, 2009,
during the rainy season. Additional surveys were conducted concurrent with fairy shrimp
surveys on February 2 and 12, and March 10, 2010.

Western spadefoot toad

The quarry expansion area provides no breeding or aestivation habitat for the species and
therefore no avoidance or mitigation measures are necessary. Furthermore, western
spadefoot toads, their larvae, or egg masses were not found at any location within the
greater Project site.



                                               1-4
                        CALIFORNIA VALLEY SOLAR RANCH PROJECT
              TWISSELMAN QUARRY BIOLOGICAL RESOURCES SUMMARY

Reptiles

Nine distinct reptile taxa were detected during focused transect surveys of portions of the
CVSR Project site south of SR 58 and they are likely to occur in the quarry expansion
area. These species include the side-blotched lizard (Uta stansburiana), coast horned
lizard (Phrynosoma blainvillii), California whiptail (Aspidoscelis tigris mundus), western
fence lizard (Sceloporus occidentalis), western red-tailed skink (Plestiodon gilberti
rubricaudatus) and California kingsnake (Lampropeltis getula californiae), northern
Pacific rattlesnake (Crotalus oreganos), Pacific gopher snake (Pituophis catenifer
catenifer), and San Joaquin coachwhip (Masticophis flagellum ruddocki).

Two of the nine reptile taxa detected during biological field surveys of the CVSR Project
site are special-status species; the coast horned lizard and San Joaquin coachwhip. The
potential for these species and the potential for blunt-nosed leopard lizard (Gambelia sila)
and the silvery legless lizard (Anniella pulchra pulchra), to occur within the quarry
expansion area was assessed.

Coast horned lizard

No individuals were detected during surveys conducted near the aggregate quarry or
buffer area around the quarry and habitat conditions there are generally unfavorable for
this species. Nonetheless, there is a small portion of the buffer area to the northeast of
the mine comprised of rolling grassland with California ground squirrel burrows that may
provide marginal habitat for the species. Expansion of the quarry will result in the loss of
approximately 14 acres of potentially suitable grassland habitat and direct mortality to
aestivating or foraging individuals. Implementation of M-BIO 21-23 would reduce the
potential impact to this species.

San Joaquin coachwhip

While the quarry itself does not contain adequate habitat for this species, the loss of
approximately 14 acres of potentially suitable grassland habitat resulting from expansion
of the quarry could affect the species through loss of prey base, aestivation and foraging
habitat, and direct mortality. Implementation of M-BIO 21-23 would reduce the potential
impact to this species.

Blunt-nosed leopard lizard

The quarry area is generally unfavorable for the occurrence of blunt-nosed leopard lizard,
however, rodent burrows (which provide potential refugia) are abundant, and the
grassland northeast of the site provides potential foraging habitat for the species. The
loss of approximately 14 acres of grassland habitat and small mammal burrows resulting
from quarry expansion could potentially reduce foraging and aestivation opportunities for

                                              1-5
                         CALIFORNIA VALLEY SOLAR RANCH PROJECT
               TWISSELMAN QUARRY BIOLOGICAL RESOURCES SUMMARY

the species, but implementation of mitigation measures M-BIO 13-20 would reduce or
avoid impacts to blunt-nosed leopard lizard.

Silvery legless lizard

Two important components of silvery legless lizard habitat are lacking within the quarry
expansion are: moist soils and a layer of plant (leaf) litter. In addition, the site is heavily
impacted by livestock grazing through much of the year, and soils throughout the site are
disturbed and compacted by cattle. Such activity can affect this species through both
habitat alteration and trampling. The quarry area provides no habitat for the species and
therefore no avoidance or mitigation measures are required.

BIRDS

Habitat suitability for special-status birds at the Twisselman Quarry was assessed on 12
October 2009 by H. T. Harvey & Associates ecologist Steve Rottenborn, Ph.D. Although
the active quarry areas provide only low-quality foraging habitat, at best, for special-
status birds, the 14 acres of annual grassland surrounding the active quarry provide
foraging habitat for a number of special-status bird species. Such species include the
golden eagle (Aquila chrysaetos) and white-tailed kite (Elanus leucurus), both of which
are State Fully Protected species, as well as six California Species of Special Concern:
the burrowing owl (Athene cunicularia), grasshopper sparrow (Ammodramus
savannarum), loggerhead shrike (Lanius ludovicianus), long-eared owl (Asio otus),
northern harrier (Circus cyaneus), and vesper sparrow (Pooecetes gramineus). As a
result, the primary impact of quarry expansion will be the loss of 14 acres of foraging
habitat for these birds.

The only special-status bird species that could potentially nest in the quarry expansion
area are the burrowing owl and grasshopper sparrow. No burrowing owls have been
observed at the quarry, and no burrows suitable for the species were observed within the
quarry expansion area during focused mammal surveys (described below). However, if
California ground squirrels (Spermophilus beecheyi), San Joaquin kit fox (Vulpes
macrotis mutica), or American badgers (Taxidea taxus) excavate burrows in or near the
expansion area, they could potentially be used as nesting or roosting sites for burrowing
owls after the mammals have vacated the burrows. If burrowing owls nest or roost in the
quarry expansion area, quarry operation could result in the loss of up to 14 acres of
breeding and roosting habitat, and the injury or mortality of owls if occupied burrows are
destroyed by heavy equipment. Active nests could be disturbed, possibly to the point of
abandonment of eggs or young, by noise, people, and movement of heavy equipment
associated with the quarry. Measures to mitigate these impacts, such as pre-construction
surveys and maintenance of buffers around active nests during the breeding season, are
described in Mitigation Measures M BIO-38 through M BIO-40 in Section 11 of the

                                               1-6
                        CALIFORNIA VALLEY SOLAR RANCH PROJECT
              TWISSELMAN QUARRY BIOLOGICAL RESOURCES SUMMARY

Biological Resources Assessment Report. No more than one or two pairs of grasshopper
sparrows (if any) are expected to nest within the quarry expansion area. Although quarry
expansion during the breeding season could potentially result in the destruction or
abandonment of active nests, including eggs and young, as well as the loss of up to 14
acres of potential breeding habitat, such an impact on grasshopper sparrows would be less
than significant given the regional abundance of the species, and no mitigation would be
required.

MAMMALS

H. T. Harvey & Associates biologists Robert Burton Ph.D. and Darren Newman
conducted surveys for special status mammals with a focus on giant kangaroo rat
(Dipodomys ingens), San Joaquin antelope squirrel (Ammospermophilus nelsoni), San
Joaquin kit fox, and American badger. The Twisselman quarry and surrounding area was
surveyed for occurrence of mammals on 14 December, 2009. High-resolution aerial
photographs of the quarry expansion areas, the access road extending north to the quarry,
and the quarry served as a base map which was overlain with a north-south oriented grid
comprised of cells measuring 2500 meter2 (Figure 2). The 50 x 50 meter grid squares
were visually searched for important habitat types, topographic features, giant kangaroo
rat precincts, and evidence indicating presence of San Joaquin antelope squirrel, San
Joaquin kit fox, or American badger. Each grid cell was identified as either 1) containing
at least one active giant kangaroo rat precinct; 2) containing at least one inactive giant
kangaroo rat precinct; 3) containing at least one active San Joaquin antelope squirrel
burrow; 4) containing shrub habitat suitable for San Joaquin antelope squirrel; 5)
containing evidence that San Joaquin kit fox or American badger are present, or were
present in the recent past, and 6) containing no evidence of these special status mammal
species. A Panasonic CF-19 Toughbook computer (Panasonic Corporation of America,
Secaucus, NJ) connected to a Garmin GPSmap76 (Garmin International Inc., Olathe, KS)
enabled real-time tracking of a surveyor’s position with ARCGIS software and the base
map and grid. Low relief areas to the west and east of the quarry (show in Figure 2) were
also searched for evidence of special status mammals even though beyond the survey
grid.

Small Mammals

The topography is relatively steep along the northern, eastern, and southern perimeter of
the quarry. This steep habitat is unsuitable for giant kangaroo rats, which show a strong
preference for gently sloped open grasslands more typical of the valley floor. The low
relief area to the southwest of the quarry is potentially suitable habitat for giant kangaroo
rats although they are unlikely to occur there due to the small size of the area and the fact
that it is surrounded by relatively steep topography. San Joaquin antelope squirrels are
also not expected to occur on the steep slopes, and although the flat area to the southwest

                                              1-7
                                Legend                                                                              Scale
                                        Additional Survey Area Boundary
                                                                                                                                                                                                                California Valley Solar Ranch
                                                                                                                                                         1:3,000                                             Twisselman Quarry Biological Resources Summary
                                         Survey Areas (50m x 50m Blocks)

                                         Areas of Suitable Nelson's Antelope Squirrel Habitat                                                  1 inch = 250 feet                                             Figure 2 - Survey Areas and NAS Detection Locations
N:\Projects\3103-01\Report\




                                                                                                                       0               125                250                                  500 Feet

                              Data Sources: [1] H.T. Harvey & Associates survey data, [2] USDA NAIP Aerial (2009)   Coordinate System: North American Datum 83 Universal Trans Mecator (UTM) Zone 11 North
                         CALIFORNIA VALLEY SOLAR RANCH PROJECT
               TWISSELMAN QUARRY BIOLOGICAL RESOURCES SUMMARY


could potentially support antelope squirrels, it is unlikely due to the lack of suitable
vegetation. We found no evidence that giant kangaroo rats or San Joaquin antelope
squirrels occur within the existing footprint of the quarry or in the immediate surrounding
area. Habitat that is potentially suitable for San Joaquin antelope squirrels was identified
to the south of the quarry (Figure 2), and H. T. Harvey & Associates will be conducting
live-trapping surveys in this habitat during spring 2010.

There are California Species of Special Concern that potentially occur within the vicinity
of the quarry, including the short-nosed kangaroo rat (Dipodomys nitratoides brevinasus)
and Tulare grasshopper mouse (Onychomys torridus tularensis). Short-nosed kangaroo
rats typically inhabit highly saline soils around Soda Lake on the Carrizo Plain. Yet they
can also be found on hilltops in desert-shrub associations and sparingly on steep rocky
hillsides among chaparral up to elevations of 2,750 feet. Tulare grasshopper mice inhabit
arid shrubland communities and arid grassland and shrubland associations. These include
blue oak woodlands at 1476 feet; upper Sonoran subshrub scrub communities; alkali sink
and mesquite associations on the San Joaquin Valley floor; and grassland associations on
the sloping margins of the San Joaquin Valley and Carrizo Plain region. Although both
of these species could occur throughout the areas surrounding the quarry, no direct
evidence of their presence was observed during surveys. Expansion of the quarry could
potentially result in loss of 14 acres of habitat for these species and direct mortality if
occupied burrows are excavated.

San Joaquin Kit Fox and Other Medium Sized Mammals

San Joaquin kit fox, a federally endangered species, are not expected to use the steeper
slopes but very likely occur throughout the rolling hills east of the quarry as well as
throughout the low relief areas south and southwest of the quarry. A San Joaquin kit fox
was observed less than 0.5 miles south of the quarry during spotlight surveys and a
potential den was found ~0.5 miles south of the quarry. San Joaquin kit fox very likely
forage throughout the lower relief areas south and east of the quarry. Expansion of the
quarry would result in the loss of 14 acres of foraging habitat for kit fox and a significant
increase in activity or traffic could result in direct mortality as a result of vehicle collision
or displacement of San Joaquin kit fox from the area. Mitigation measures will be
implemented to avoid impacts to San Joaquin kit fox (M BIO 46-56).

The American badger, a California Species of Special Concern, is known to occur in the
region. American Badgers could potentially occur throughout the area around the quarry
and may even occasionally wander through the quarry in search of prey. A potential
badger den was located ~1.0 mile south of the quarry. In some areas of the American
badger range, vehicle collisions are the primary cause of mortality. Expansion of the
quarry would result in the loss of 14 acres of foraging habitat for badgers and significant


                                                1-9
                         CALIFORNIA VALLEY SOLAR RANCH PROJECT
               TWISSELMAN QUARRY BIOLOGICAL RESOURCES SUMMARY

increase in activity or traffic could result in direct mortality as a result of vehicle collision
or displacement of badgers from the area. Mitigation measures will be implemented to
avoid impacts to American badgers (M BIO 72-76).


Uncommon Game Mammals

Tule elk (Cervus canadensis nannodes) distribution data obtained from CDFG indicates
that the Carrizo Plain tule elk range is north of SR 58 between Bitterwater Road and the
Temblor Range. Tule elk have been observed in areas of the Project site north of SR 58
in the vicinity of the generation tie-line, during aerial surveys (CDFG data, Dave Hacker,
CDFG, pers. comm.). Tule elk are expected to occur in lower relief areas around the
quarry possibly foraging or moving through the area. Expansion of the quarry would
result in loss of 14 acres of tule elk habitat. Elk, however, have very large home ranges,
and the expected loss of habitat is not likely to be a significant impact. Tule elk may be
displaced from the area if activity and traffic around the quarry substantially increases,
but this effect would be limited to the construction phase of the project.

Pronghorn antelope (Antilocapra americana) are also known to occur throughout the
Carrizo Plain region and have been observed on numerous occasions north of SR 58, in
the general vicinity of the quarry. Pronghorn antelope are expected to occur around the
quarry possibly foraging or moving through the area; they may also potentially enter the
quarry seeking water if it were to pool in excavated areas. Expansion of the quarry
would result in the loss of 14 acres of pronghorn antelope habitat. Pronghorn may be
displaced from the area if activity and traffic around the quarry substantially increases,
but this effect would be limited to the construction phase of the project.




                                                1-10