CHAPTER 12 VALLEY PLANT ATTACHMENTS

Attachment - KRV - 63896, 65562, 65590, 67589 1 (Kern Canyon documents) Attachment - KRV - 66170 1 (2011 Sanitary Survey Report) Attachment - KRV - 66170 2 (Drinking Water Program) Attachment - KRV - 66170 3 (Excerpt from CH16 of WWS) Attachment - KRV - 71153 1 (Tank Inspection Report)

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A seismic fault in the , believed to Most Read | Most Commented 0 0 have been quiet for more than 3 million years, is 1. Flash sales: Homes snapped up in 24 hours Like active after all and capable of triggering strong 2. Former NBA player trashes his foreclosed quakes with magnitudes of 6 or even 7, home Comments (0) Email This 3. Tumbling boulder hits SUV on 101 scientists say. 4. Man finds grenade in Golden Gate Park Larger | Smaller Font 5. Road Movies Printable Version The Kern Canyon Fault, stretching for nearly 90 6. Ex-Titans cheerleader arrested for soliciting miles from north to south above the San Joaquin boy 7. 6 Ways The iPhone 5 Still Outshines Valley east of Bakersfield, cuts beneath a major Samsung's Galaxy S4 (AAPL, GOOG) flood control dam on the Kern River.

Today's Deal For a half-dozen years those who oversee the 57-year-old Isabella flood control dam above $49 -- All-Day Salmon or Cod Deep Sea Bakersfield, as well as Institute of Technology geologists, have been studying Fishing off Monterey the fault closely. SALE ENDS IN "It came as a surprise to see that a long-inactive fault can produce significant quakes," said 2d:13h:42m geologist Elisabeth Nadin of Caltech, who has hiked the sparsely populated rugged terrain PRICE and mapped where evidence showed the fault ruptured violently at least 3,300 years ago. $49

Geologists working for the Army Corps of Engineers have also studied the fault's potential for rupturing and are surveying the dam to determine whether it needs strengthening against future large quakes.

The fault emerged some 86 million years ago when the immense granite mass of the Sierra was uplifting, said Nadin, who has found the evidence of past violence in the rocks around it.

For millions of years, the mountains around the fault rose and subsided again. Volcanic activity continued, and a pulse of volcanism about 3.5 million years ago left a lava flow at the fault's northern end, she said. Nadin said, "Seismic activity on the fault continues today."

Nadin, who just received her doctorate from Caltech, and her former Caltech adviser, Jason B. Saleeby who has also studied the fault, are publishing results of their findings in 699 http://www.sfgate.com/bayarea/article/Inactive-fault-may-trigger-big-quake-after-all-3258998.php 3/22/2013 Inactive fault may trigger big quake after all - SFGate Page 2 of 3 the September issue ofKRV the Bulletin of the63896_65562_65590_67589 Geological Society of America. FROM OUR HOMEPAGE 1 Typical of the evidence for recent temblors that Nadin cited are a series of "fault scarps" - small jagged cliffs 6 feet or more high - that run along the west side of the fault and indicate where the land was abruptly lifted up by the force of a quake. Those scarps, she said, show little evidence of erosion - a sign that they were uplifted relatively recently.

During her field explorations along the fault, Nadin said, she also found scores of rounded boulders - deposits from a period of intense glaciation some 12,000 years ago - that had been lifted up from deep beneath the surface by much more recent activity. Devil’s Slide drive nears end This is the last weekend to take the dizzying, dangerous drive on Hwy. 1 before tunnels finally Ronn S. Rose, the dam safety program manager for the Army Engineers in Sacramento, open. and Keith I. Kelson, senior geologist at the earthquake consulting firm of Fugro William Lettis & Associates in Walnut Creek, are among a group of specialists surveying the fault because of potential hazard to the dam.

They have also studied evidence of recent seismic slip along the fault with a series of six deep trenches, isotope studies and drilling to reveal the ages of past quakes there.

Rose, Kelson and other geologists working for the Corps of Engineers said in a recent report that their evidence suggests that the Kern Canyon Fault could generate Road movies: Hot and not As 'On the Road' opens, a look at many film with magnitudes "from 6.5 to perhaps 7.5." journeys, some great, like this erotic trip, others a slog. Kelson said in an interview that the two-unit dam is considered a "critical facility" because the fault runs directly beneath one abutment of the dam's auxiliary unit.

"It would likely cost hundreds of millions of dollars to replace it in the event of complete failure," he said.

Although there is good evidence to determine the "slip rate" of recent movement along the fault, Rose said, it appears to be moving far more slowly than the annual slip rate along the Why so snarky, daddy? - "a hundred times slower," he said in an interview. Gossip blogger Perez Hilton insists he'll change his ways as he releases photos of son. The was built in 1953, primarily for flood control along the Kern River and to provide irrigation water for major Kern County farms around Bakersfield.

In her study, Nadin noted that many active faults lie in the region, notably the Garlock and White Wolf faults.

Whether those two have links deep underground to the Kern Canyon Fault is unknown, she said. The is considered potentially dangerous today because it ruptured violently in 1952 with a magnitude 7.3 quake that killed 12 in the tiny town of Tehachapi.

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gfedc Remember Me Sign In 700 http://www.sfgate.com/bayarea/article/Inactive-fault-may-trigger-big-quake-after-all-3258998.php 3/22/2013 Corps of Engineers studies risk of fault under Dam | Article | The United States Army Page 1 of 3

Homepage > News Archives > Article KRV 63896_65562_65590_67589 1

Corps of Engineers studies risk of fault under Lake Isabella Dam

October 30, 2009

By Mr. William Byrd (USACE)

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Story Highlights z The Sacramento District is studying fault activity near the Lake Isabella auxiliary dam. z Engineers and geologists are digging a series of trenches and boring deep holes to study soil samples. z Studies revealed that the Kern Canyon fault, which runs beneath the auxiliary dam, is capable of causing large magnitude earthquakes z Results of the studies will be used to determine what remediation measures the Corps will need to take to keep the dam safe.

LAKE ISABELLA, Calif. - Many dams throughout the world, Related Links even recently constructed ones, are located on active USACE News faults. One such dam, located at the Corps-managed Lake HQ US Army Corps of Isabella, is considered at risk after U.S. Geological Survey Engineers (USGS) studies revealed that the Kern Canyon fault, which runs beneath the auxiliary dam, is capable of US Army Corps of Engineers Sacramento District causing large magnitude earthquakes. Lake Isabella Dam Contractors working for the U.S. Army Corps of Engineers are nearing completion on a study of the fault at Lake Isabella by conducting two geotechnical exploratory actions near the auxiliary dam. Study results will be used as part of the Isabella Dam Safety Assurance Program.

701 http://www.army.mil/article/29633/Corps_of_Engineers_studies_risk_of_fault_under_Lake_Isabella_Dam/ 3/22/2013 Corps of Engineers studies risk of fault under Lake Isabella Dam | Article | The United States Army Page 2 of 3

Partnered with the Corps on the trenchingKRV and drilling 63896_65562_65590_67589 at Isabella are various trenching 1 and drilling contractors and geologists, said Tony Kittner, Isabella Dam project geologist, Sacramento District geotechnical engineering branch, who referred to some of the contractors and geologists as the "best in the world." The USGS is also performing geophysics work on the auxiliary dam and upstream in the delta region below nearby Kernville, Calif.

Workers are nearly half finished digging the roughly 1,500-foot-long seismic trench, which runs 10 to 15 feet deep and 4 feet wide and parallels the auxiliary dam approximately 100-150 feet from the toe (lowest portion) of the dam. Additionally, 21 boreholes 180-300 feet deep were drilled, part of a series of trenches that were dug in the area to study the Kern Canyon fault activity.

"The significance of the drilling is to gather geotechnical information on the dam's foundation materials, ,as well as the material in the embankments the dam is made up of," said Kittner. "We need to determine what the soil properties and characteristics at various locations and depths are and how well they are holding up, what the soil densities are and how compacted they are, plus how much of an earthquake loading they can take.

"We have to assist in evaluating the past activity on the Kern Canyon Fault," Kittner said, "and determine surface fault rupture segments, past displacement direction and amount, and provide estimates of future earthquake magnitude, recurrence interval (frequency of occurrence), and style and amount of offset. C-14 radiocarbon and OSL (optically stimulated) luminescence dating sampling methods are used for determining the age of the material found in and near the fault displacements."

A preliminary screening of possible alternatives and remediation measures for the Isabella Dam Safety Project is scheduled for December using the seismic and seepage evaluations and data collected from the field investigations, said David Serafini, Isabella Dam technical lead. The screening of alternatives will address the seepage, seismic and hydrologic deficiencies for the main dam, auxiliary dam and the spillway, he said. Findings will determine what action the Corps will take, said Kittner and Ronn Rose, geologist, dam safety program manager with the Sacramento District.

"Several measures will likely be evaluated to strengthen the Auxiliary Dam for seismic and seepage concerns," Serafini said. "The remediation of the homogeneous embankment could include the installation of filters or drains, foundation improvement or possible replacement of portions of the embankment. Seismic remedial measures may also be required for the control tower and Borel Canal conduit (channel). It is likely that a combination of all of these will be required."

Rose said results thus far reveal: the fault has been active north and south of Lake Isabella within the past 3,500 years; the fault poses surface rupture and a ground- shaking hazard to Lake Isabella; at least six events have occurred on the fault within the past 35,000 years, and the ruptures have been between 12 and 36 inches with western side up displacement.

Three locations downstream of the dams in the Isabella and Havilah Valley areas were trenched previously from October 2008 through January 2009. Three locations were trenched upstream of the dam above Kernville (Corral Creek, Rincon Springs and Brush Creek sites) also, beginning in May 2009 and completed in early July.

"The current trenching is being performed due to the USGS geophysical results that showed the extent of faulting beneath the auxiliary dam was much greater than what was originally anticipated when the dams were built," Kittner said. "Recent USGS seismic survey results recorded breaks in the bedrock beneath the entire length of the auxiliary dam and the rocks cored in deep drill holes have verified some of those results.

"The faulting and resulting poor condition of the rock found along the entire length of the auxiliary dam is believed to be caused by an older strike-slip fault that has recently reactivated as a normal or reverse fault," Kittner said. "That fault is currently mapped between the right abutment and first 800 feet of the west side of the auxiliary dam.

"Multiple seepage problems and poor foundation materials at the auxiliary dam were driving the DSAC rating for this project until it was learned the auxiliary dam was built on an active fault, a direct result of the fault trenching project," Kittner said. "That drove the risk higher due to earthquake loading and liquefaction, and made it more of a risk for the population living downstream, as well as made the entire project more complex from a dam safety and geotechnical standpoint."

"It is important to note that the Kern Canyon Fault is only one part of the seismic problem," Rose added. "There are multiple seismic sources that could cause strong 702 http://www.army.mil/article/29633/Corps_of_Engineers_studies_risk_of_fault_under_Lake_Isabella_Dam/ 3/22/2013 Corps of Engineers studies risk of fault under Lake Isabella Dam | Article | The United States Army Page 3 of 3

ground shaking at the dam. However,KRV the Kern Canyon 63896_65562_65590_67589 Fault does have the potential to 1 cause a rupture of the dam and this can be dealt with in a remedial design."

Serafini said the Corps will await the test results and then evaluate what measures might be needed to address dam remediation.

"The Corps is in the process of completing the characterization of the seepage and seismic deficiencies for the Isabella Dam Safety Project," he said. "A detailed base line risk analysis of the project is also under way and should be completed in January with the coordination of the U.S. Army Corps of Engineers Flood Risk Management Center. In December, a group of dam safety experts will be developing a short list of possible alternatives and remediation measures for the project."

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703 http://www.army.mil/article/29633/Corps_of_Engineers_studies_risk_of_fault_under_Lake_Isabella_Dam/ 3/22/2013 KRV 63896_65562_65590_67589 1

Isabella Lake Dam Safety Modification Project Environmental Impact Statement Draft

Volume I – Draft Environmental Impact Statement

March 2012

U.S. Army Corps of Engineers, Sacramento District – Lead Agency

U.S. Department of Agriculture, Forest Service Sequoia National Forest – Cooperating Agency Forest Service

704 KRV 63896_65562_65590_67589 1 3. Affected Environment and Environmental Consequences – Geology, Soils, and Seismicity and boring information indicate that the bedrock surface slopes down to the south (downstream) in Hot Springs Valley.

Naturally Occurring Asbestos Naturally occurring asbestos (NOA) is commonly found in fault zones. Asbestos is a generic term for multiple types of naturally occurring fibrous minerals distributed throughout California. Although chrysotile is the most common form of asbestos, other types (such as amphibole) are also found in California. Chrysotile asbestos is usually found in serpentine rock and its parent material, ultramafic rock. Serpentines have not been identified in geologic mapping of the Isabella Lake area, but asbestos is commonly found near fault zones.

A crystalline limestone unit was identified in the Kern Canyon Fault zone, beneath the alluvial fan materials, near the right abutment of the Auxiliary Dam (Corps 2010b), which may contain NOA. Other potential NOA regions in the project area are fault-related mafic igneous intrusions and metamorphosed marble bodies. Project areas with favorable bedrock geology for NOA are considered potentially hazardous until a site-specific investigation and lab analysis rules out NOA.

Seismicity The project area is influenced by a number of active seismic zones. Tectonically, the Sierra Nevada has been tilted westward by rapid uplift along the Zone, which forms the eastern escarpment and gentle west-sloping foothills.

The project area is in the southern part of the Sierran microplate, an independently moving block within the broad zone of distributed deformation between the Pacific Plate and the stable interior of North America (see Figure 3-3). Space-based geodesy demonstrates that the Sierran microplate moves about 13 millimeters a year to the northwest, with respect to stable North America. The motion of the Sierran microplate is directed more toward the west than the average trend of its eastern boundary, resulting in net trans-extensional deformation in the belt, a 62-mile-wide zone of active seismicity and late-Cenozoic faulting east of the Sierra Nevada (Corps 2010b).

The southern Sierra Nevada is bisected by a system of faults that form a zone nearly 100 miles long—the White Wolf Fault Zone, including the Breckenridge fault, to the south of the lake, and the Kern Canyon Fault Zone, which extends through the Isabella Lake Dam site to the north (Kleinfelder 2007). Other major active faults in the project’s vicinity are the (35 miles south), the San Andreas Fault (65 miles west), and the Owens Valley Fault (40 miles northeast).

March 2012 Isabella Lake Dam Safety Modification Project, Draft EIS 3-11 705 KRV 63896_65562_65590_67589 1 3. Affected Environment and Environmental Consequences – Geology, Soils, and Seismicity

Figure 3-3 Regional Tectonic Framework, with Features Discussed in the Text

March 2012 Isabella Lake Dam Safety Modification Project, Draft EIS 3-12 706 KRV 63896_65562_65590_67589 1 3. Affected Environment and Environmental Consequences – Geology, Soils, and Seismicity

The Garlock and San Andreas Faults are the most prominent active fault zones defining the western and southern extensions of the southern Sierra Nevada. The Owens Valley Fault defines the eastern edge of the Sierra Nevada uplift. Several large earthquakes related to these faults and affecting the Isabella Lake Dam site before and after completion in 1953 are listed in Table 3-1.

Table 3-1 Large Earthquakes Affecting the Isabella Lake Dam Site Before and After Completion in 1953 Distance from Date Fault Magnitude Isabella Dam

March 26, 1872 Lone Pine (Owens Valley) ML7.6 75 miles NE March 15, 1946 Kern County (Walker Pass) ML6.3 25 miles east July 21, 1952 White Wolf (Kern County Earthquake) ML7.5 50 miles SW July 21, 1952 White Wolf (Aftershock) ML6.4 50 miles SW July 23, 1952 White Wolf (Potential aftershock) ML6.4 50 miles SW August 22, 1952 White Wolf (Bakersfield) ML5.8 50 miles west July 11, 1992 Garlock (Mojave) MW5.7 40 miles south September 20, 1995 Kern County (Ridgecrest) Mw5.5 60 miles east May 1, 2008 Kern County (Scodie Mountains) Mw4.4 11 miles east

Notes: ML = Richter (Local) Magnitude, MW – Moment Magnitude

The Garlock Fault is 35 miles south of Isabella Lake and the project area. The Garlock Fault zone strikes east-west, defining the northern boundary of the Mojave Block, as well as the southern end of the Sierra Nevada, and valleys of the western-most Basin and Range province. It is 155 miles long, with an estimated average slip rate of 7 millimeters/year and a calculated probable maximum moment magnitude (Mw) scale Mw6.8 to Mw7.6 earthquake. There have been sizable quakes recorded along the Garlock Fault zone. Cracks opened along a short segment of the fault in 1952, due to the shaking of the Kern County earthquake, and groundwater removal also triggered a slip in the Fremont Valley area. The most recent movement on the Garlock Fault was a magnitude (M) 5.7 earthquake near the town of Mojave on July 11, 1992, and is thought to have been triggered by the Kickapoo (Landers) earthquake (M7.3) which occurred two weeks before, approximately 115 miles southeast of the Garlock Fault zone. Despite the Kickapoo Fault’s short length and previously hidden nature, it broke with a maximum of nearly 9.5 feet of right-lateral displacement ( Earthquake Data Center 2010).

The San Andreas Fault forms a major tectonic boundary between the Pacific Plate and the North American Plate. The San Andreas Fault is an active, continental transform fault that runs a length of roughly 810 miles through California. It displays right lateral strike- slip movement with an average slip rate of about 35 millimeters per year. Although 65 miles west of the project site, movement on the San Andreas Fault with a calculated probable Mw6.8 to Mw8.0 or larger earthquake potential, may cause serious seismic impacts at the project site. The Fort Tejon earthquake of 1857 (M7.9) was one of the greatest earthquakes ever recorded in the United States and left an amazing surface

March 2012 Isabella Lake Dam Safety Modification Project, Draft EIS 3-13 707 KRV 63896_65562_65590_67589 1 3. Affected Environment and Environmental Consequences – Geology, Soils, and Seismicity rupture scar over 218 miles long, with an average of 15 feet of displacement, up to a maximum of 30 feet, along the San Andreas Fault. The Fort Tejon earthquake rupture was about 60 miles southwest of Isabella Lake. As a result of the shaking, the current of the Kern River was turned upstream, and water ran four feet deep over its banks. Serious ground motion effects were recorded throughout the central California region (Southern California Earthquake Data Center 2010).

The Owens Valley Fault generally strikes north along the Sierra Nevada escarpment and extends from Little Lake to Big Pine, California. The 1872 Owens Valley Fault earthquake (M7.6) occurred near Lone Pine, approximately 65 miles northeast of Isabella Lake, and involved both dip-slip and right-lateral components of movement (US Geological Survey [USGS] 2010). The most surface deformation and rupture were observed between the towns of Lone Pine and Independence, but cracks formed in the ground as far north as Bishop. The largest horizontal displacement was 21 feet, with an average vertical 3 feet of relative uplift. The shock was felt over most of California and much of Nevada, and thousands of aftershocks occurred, some of which were severe (Southern California Earthquake Data Center 2010).

The White Wolf Fault is a left-lateral reverse fault estimated at 37 miles long, with an average slip rate of 3.0 to 8.5 millimeters a year and a calculated probable maximum magnitude of Mw6.5 to M7.5. Recent rupture on the White Wolf Fault during the 1952 Kern County earthquake (M7.5) caused widespread damage (Southern California Earthquake Data Center 2010). The Breckenridge Fault extends between the White Wolf Fault and Kern Canyon Fault and is a normal fault approximately 19 miles long (Figure 3-3). The fault dip varies from vertical to steeply east-dipping. The White Wolf Fault is not believed to be structurally connected to the Kern Canyon Fault.

The Kern Canyon Fault zone is the only active structural zone that breaks the interior of the , disrupting the structural coherency of the batholith. Its longevity and geometry make it well positioned to accommodate the present regional east-west extensional stress field. Structural, geomorphic, geodetic, and seismic observations indicate that the Kern Canyon Fault system has undergone Quaternary reactivation as a series of west-side-up normal fault scarps along its 81-mile length (Nadin and Saleeby 2010). Historically, the Kern Canyon Fault has been considered inactive by seismologists, but recent studies have shown otherwise. Through field studies concluding in 2010, the Corps determined that the Kern Canyon Fault is active and assessed it to be capable of a M7.5 earthquake. The recently concluded fault study show that that slip is almost purely normal and is estimated at about 0.3 millimeter a year. The conclusive evidence that led to the determination that the Kern Canyon Fault is Holocene active was primarily dateable offsets in recent alluvium. Three surface rupturing events have been seen in the last 11,000 years (Holocene). The average recurrence interval for surface rupturing earthquakes is estimated at about 3,200 years URS 2010.

The Kern Canyon Fault intersects the Auxiliary Dam right abutment. The fault’s uplifted block forms a ridge that divides the Kern River Canyon from Hot Springs Valley and

March 2012 Isabella Lake Dam Safety Modification Project, Draft EIS 3-14 708 KRV 63896_65562_65590_67589 1 3. Affected Environment and Environmental Consequences – Geology, Soils, and Seismicity projects northeast next to the right abutment of the dam as an elongated spur (Engineers Point) into Isabella Lake (Figures 3-1, 3-2, and 3-3). Seismic profiling along the Auxiliary Dam’s toe shows multiple splays in the Kern Canyon Fault zone (see Figures 3- 4 and 3-5).

At the Main Dam, although most of the foundation is hard granitic rock and presents no concerns from a geologic standpoint, numerous joints and faults exist in the foundation and are transverse to the dam’s axis. The largest fault in the foundation is at the outlet works control tower. These faults are not believed to be active seismogenic sources but likely reflect subsidiary faults associated with strike-slip movement on the Kern Canyon Fault millions of years ago. It is unknown if a major earthquake on the Kern Canyon Fault would cause any movement today on these faults beneath the Main Dam foundation (Corps 2010b).

A splay of the Kern Canyon Fault, the Big Blue Fault, parallels the Kern Canyon Fault to the north, along the North Fork of the Kern River as it enters Isabella Lake (Kleinfelder 2007). The Big Blue-Sumner is a sheared and faulted zone, as much as 125 feet wide, that strikes N30ºE and dips 70ºNW. Innumerable subordinate faults, splits, and sheared zones comprise the main shear zone. The Big Blue Fault is not listed as an active fault, but as a splay of the active Kern Canyon fault, should be considered active. It is not known if the Big Blue Fault represents that active strand of the fault or if the active strand is buried by recent sediments in the north fork of the reservoir (California Geological Survey 2010b, URS 2010).

New results on recent fault activity along the Kern Canyon Fault was presented as part of a larger study of the fault commissioned by the Corps Dam Safety Program to define earthquake hazards to the dams that impound Isabella Lake (Earth & Climate 2010). The Corps commissioned an airborne topographic survey of the fault zone using light detection and ranging (LiDAR), an optical remote sensing technology, to image the fault zone in areas of dense vegetation and rugged terrain typical of the remote Kern Canyon. This survey provided critical information on the location of previously undiscovered ground-surface breaks, or fault scarps, along the Kern Canyon Fault that formed during large historic earthquakes. The LiDAR survey was used to quantify the rate of movement of the Kern Canyon Fault over the past about 20,000 years at a site called Soda Spring, where the fault scarp cuts glacial moraines that formed during the last major ice age. Modern geochemical techniques were used to date the formation of these moraines and to calculate an average rate of fault movement of at least 0.2 millimeter a year over this time at Soda Spring.

Although individual earthquakes on the Kern Canyon Fault may shift the ground surface up to a meter and a half nearly instantaneously, the average slip rate includes the time between earthquakes, which ranges between hundreds and thousands of years for the Kern Canyon Fault (Amos et al. 2010).

March 2012 Isabella Lake Dam Safety Modification Project, Draft EIS 3-15 709 KRV 63896_65562_65590_67589 1 3. Affected Environment and Environmental Consequences – Geology, Soils, and Seismicity

Figure 3-4 Oblique Aerial photograph of Engineer Point

March 2012 Isabella Lake Dam Safety Modification Project, Draft EIS 3-16 710 Recent Earthquakes for 118-36 Page 1 of 3 KRV 63896_65562_65590_67589 1

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MAG DATE LOCAL-TIME LAT LON DEPTH LOCATION y/m/d h:m:s deg deg km

2.7 2013/03/22 04:50:14 35.721N 117.525W 10.5 15 km ( 9 mi) WSW of Trona, CA 0.5 2013/03/22 04:44:15 36.027N 117.779W 2.7 15 km (10 mi) E of Coso Junction, CA 1.7 2013/03/22 04:17:06 35.378N 118.536W 2.1 29 km (18 mi) NNW of Tehachapi, CA 0.8 2013/03/22 01:46:18 36.030N 117.776W 2.4 16 km (10 mi) E of Coso Junction, CA 2.4 2013/03/21 19:27:21 35.996N 117.634W 19.7 29 km (18 mi) E of Coso Junction, CA 2.0 2013/03/21 19:18:41 36.023N 117.778W 2.8 15 km (10 mi) E of Coso Junction, CA 1.0 2013/03/21 17:48:02 35.939N 117.668W 1.8 28 km (17 mi) ESE of Coso Junction, CA 0.5 2013/03/21 16:47:47 35.834N 117.676W 2.1 24 km (15 mi) N of Ridgecrest, CA 0.9 2013/03/21 15:06:17 36.032N 117.775W 1.9 16 km (10 mi) E of Coso Junction, CA 0.3 2013/03/21 13:57:06 36.027N 117.776W 2.0 16 km (10 mi) E of Coso Junction, CA 1.5 2013/03/21 12:38:09 35.375N 118.533W 9.5 28 km (18 mi) NNW of Tehachapi, CA 0.9 2013/03/21 12:15:51 35.941N 117.668W 2.3 28 km (17 mi) ESE of Coso Junction, CA 0.5 2013/03/21 12:09:45 36.155N 117.866W 3.8 14 km ( 9 mi) NNE of Coso Junction, CA 0.7 2013/03/21 11:24:00 36.020N 117.791W 1.6 14 km ( 9 mi) E of Coso Junction, CA 0.3 2013/03/21 10:52:00 35.907N 117.722W 0.7 25 km (16 mi) SE of Coso Junction, CA 1.3 2013/03/21 10:44:36 35.948N 117.666W 2.6 28 km (17 mi) ESE of Coso Junction, CA 711 http://www.data.scec.org/recenteqs/Maps/118-36.html 3/22/2013 Recent Earthquakes for 118-36 Page 2 of 3

1.0 2013/03/21 09:42:05 35.879N 118.351W 3.9 27 km (17 mi) E of Pine Flat, CA KRV 1.6 2013/03/21 63896_65562_65590_67589 09:39:57 35.948N 117.666W 2.4 28 km (17 mi) ESE of Coso Junction, 1 CA 0.8 2013/03/21 09:24:11 36.030N 117.779W 2.1 15 km (10 mi) E of Coso Junction, CA 2.0 2013/03/21 08:28:28 35.028N 118.981W 13.2 4 km ( 3 mi) NW of Wheeler Ridge, CA 1.3 2013/03/21 06:49:23 35.563N 118.512W 0.0 9 km ( 6 mi) SSW of town of Lake Isabella, CA 0.3 2013/03/21 06:29:13 36.031N 117.782W 1.7 15 km ( 9 mi) E of Coso Junction, CA 0.5 2013/03/21 04:46:32 35.941N 117.670W 2.7 28 km (17 mi) ESE of Coso Junction, CA -0.2 2013/03/21 04:27:48 36.020N 117.769W 1.6 16 km (10 mi) E of Coso Junction, CA 1.1 2013/03/21 04:13:51 35.945N 117.669W 2.5 27 km (17 mi) ESE of Coso Junction, CA 1.4 2013/03/21 04:12:44 35.947N 117.667W 2.4 28 km (17 mi) ESE of Coso Junction, CA 0.4 2013/03/21 03:47:29 35.944N 117.669W 2.8 28 km (17 mi) ESE of Coso Junction, CA 0.9 2013/03/21 03:45:36 35.941N 117.669W 2.7 28 km (17 mi) ESE of Coso Junction, CA 0.3 2013/03/21 03:25:49 35.946N 117.668W 2.8 27 km (17 mi) ESE of Coso Junction, CA 1.0 2013/03/21 03:20:47 35.944N 117.665W 2.0 28 km (17 mi) ESE of Coso Junction, CA 0.7 2013/03/21 03:14:03 35.948N 117.667W 2.8 28 km (17 mi) ESE of Coso Junction, CA 1.4 2013/03/21 03:11:15 35.944N 117.670W 2.6 27 km (17 mi) ESE of Coso Junction, CA 2.8 2013/03/21 03:07:05 35.946N 117.665W 2.2 28 km (17 mi) ESE of Coso Junction, CA 0.8 2013/03/21 02:48:12 36.024N 117.779W 2.8 15 km (10 mi) E of Coso Junction, CA 0.1 2013/03/21 01:56:16 36.029N 117.778W 2.5 15 km (10 mi) E of Coso Junction, CA 1.0 2013/03/21 01:45:40 36.023N 117.771W 2.2 16 km (10 mi) E of Coso Junction, CA -0.1 2013/03/21 01:44:41 36.025N 117.773W 1.9 16 km (10 mi) E of Coso Junction, CA -0.2 2013/03/21 00:28:13 36.021N 117.776W 2.0 16 km (10 mi) E of Coso Junction, CA 0.1 2013/03/20 23:50:15 36.039N 117.772W 2.1 16 km (10 mi) E of Coso Junction, CA 0.7 2013/03/20 23:37:45 36.040N 117.774W 2.4 16 km (10 mi) E of Coso Junction, CA 1.0 2013/03/20 23:37:32 36.038N 117.775W 2.4 16 km (10 mi) E of Coso Junction, CA 1.5 2013/03/20 23:36:53 36.039N 117.773W 2.1 16 km (10 mi) E of Coso Junction, CA 0.2 2013/03/20 23:27:17 36.022N 117.775W 2.1 16 km (10 mi) E of Coso Junction, CA 0.9 2013/03/20 23:10:34 36.020N 117.775W 2.5 16 km (10 mi) E of Coso Junction, CA 0.1 2013/03/20 22:41:34 36.039N 117.775W 1.2 16 km (10 mi) E of Coso Junction, CA 1.2 2013/03/20 22:36:14 35.865N 118.103W 11.5 24 km (15 mi) SW of Coso Junction, CA 0.1 2013/03/20 22:03:46 36.037N 117.775W 1.9 16 km (10 mi) E of Coso Junction, CA 1.0 2013/03/20 22:00:11 36.038N 117.782W 2.6 15 km ( 9 mi) E of Coso Junction, CA -0.1 2013/03/20 21:48:41 36.037N 117.777W 2.2 15 km (10 mi) E of Coso Junction, CA 1.3 2013/03/20 19:31:01 35.834N 117.683W 2.9 24 km (15 mi) N of Ridgecrest, CA 1.5 2013/03/20 16:03:19 35.035N 117.684W 0.0 5 km ( 3 mi) NW of Boron, CA 0.7 2013/03/20 15:27:17 36.154N 118.240W 7.8 25 km (16 mi) SW of Olancha, CA -0.2 2013/03/20 13:08:28 36.037N 117.806W 4.1 13 km ( 8 mi) E of Coso Junction, CA 0.5 2013/03/20 11:59:44 36.148N 118.213W 7.0 24 km (15 mi) SW of Olancha, CA 0.8 2013/03/20 11:25:14 36.020N 117.777W 2.6 16 km (10 mi) E of Coso Junction, CA 1.4 2013/03/20 09:37:10 36.111N 117.921W 8.7 8 km ( 5 mi) NNE of Coso Junction, CA 0.7 2013/03/20 08:42:34 36.109N 118.052W 0.7 12 km ( 7 mi) NW of Coso Junction, CA 1.2 2013/03/20 06:59:41 35.088N 118.748W 9.3 15 km ( 9 mi) SSE of Arvin, CA 1.2 2013/03/20 06:25:19 35.642N 118.304W 9.2 15 km ( 9 mi) E of town of Lake Isabella, CA 2.0 2013/03/20 05:57:01 36.150N 118.243W 4.8 26 km (16 mi) SW of Olancha, CA 0.7 2013/03/20 01:25:38 36.214N 118.330W 10.7 30 km (19 mi) WSW of Olancha, CA 1.4 2013/03/19 21:23:25 36.084N 117.845W 1.7 10 km ( 6 mi) ENE of Coso Junction, CA -0.1 2013/03/19 21:12:17 35.908N 117.921W 2.4 15 km (10 mi) S of Coso Junction, CA 0.5 2013/03/19 20:29:36 36.134N 117.681W 6.5 26 km (16 mi) ENE of Coso Junction, CA 0.9 2013/03/19 17:18:33 36.030N 117.779W 2.7 15 km ( 9 mi) E of Coso Junction, CA 1.2 2013/03/19 12:29:36 36.419N 117.849W 9.9 21 km (13 mi) NE of Olancha, CA -0.2 2013/03/19 12:23:44 36.023N 117.775W 2.8 16 km (10 mi) E of Coso Junction, CA 1.5 2013/03/19 11:58:25 35.153N 118.390W 0.0 6 km ( 4 mi) ENE of Tehachapi, CA 0.6 2013/03/19 09:54:21 36.112N 117.867W 4.9 10 km ( 7 mi) NE of Coso Junction, CA 0.1 2013/03/19 07:50:05 36.020N 117.777W 2.6 16 km (10 mi) E of Coso Junction, CA 0.2 2013/03/19 06:01:28 36.009N 117.819W 3.5 12 km ( 8 mi) ESE of Coso Junction, CA 1.1 2013/03/19 04:12:02 36.012N 117.813W 2.2 13 km ( 8 mi) ESE of Coso Junction, CA -0.1 2013/03/19 01:31:10 35.832N 117.680W 6.8 23 km (15 mi) N of Ridgecrest, CA 0.5 2013/03/19 01:30:32 35.924N 117.689W 3.5 27 km (17 mi) ESE of Coso Junction, CA 0.9 2013/03/19 00:55:43 36.119N 117.594W 9.4 33 km (20 mi) ENE of Coso Junction, CA 1.0 2013/03/19 00:40:57 35.921N 117.688W 2.9 27 km (17 mi) ESE of Coso Junction, CA 0.7 2013/03/18 22:01:37 35.922N 117.689W 3.4 27 km (17 mi) ESE of Coso Junction, CA 0.9 2013/03/18 19:34:25 36.022N 117.774W 2.6 16 km (10 mi) E of Coso Junction, CA 1.0 2013/03/18 19:31:53 36.023N 117.771W 2.4 16 km (10 mi) E of Coso Junction, CA -0.1 2013/03/18 19:30:48 36.024N 117.772W 2.3 16 km (10 mi) E of Coso Junction, CA 0.1 2013/03/18 19:29:55 36.023N 117.770W 2.3 16 km (10 mi) E of Coso Junction, CA 1.6 2013/03/18 19:27:17 36.024N 117.772W 2.0 16 km (10 mi) E of Coso Junction, CA 0.2 2013/03/18 15:00:57 36.020N 117.767W 2.6 17 km (10 mi) E of Coso Junction, CA 0.2 2013/03/18 06:02:26 36.028N 117.778W 2.8 15 km (10 mi) E of Coso Junction, CA 1.1 2013/03/18 05:49:28 35.838N 117.682W 2.8 24 km (15 mi) N of Ridgecrest, CA 0.1 2013/03/18 04:34:50 35.828N 117.678W 6.1 23 km (14 mi) N of Ridgecrest, CA 0.5 2013/03/18 03:28:08 35.834N 117.677W 3.3 24 km (15 mi) N of Ridgecrest, CA 0.2 2013/03/18 02:34:28 35.840N 117.679W 2.2 24 km (15 mi) N of Ridgecrest, CA 712 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0.5 2013/03/17 20:43:27 36.023N 117.770W 2.0 16 km (10 mi) E of Coso Junction, CA KRV 0.9 2013/03/17 63896_65562_65590_67589 19:00:03 36.100N 117.873W 5.9 9 km ( 6 mi) NE of Coso Junction, 1 CA 1.3 2013/03/17 18:24:04 35.397N 118.716W 8.1 24 km (15 mi) NNE of Arvin, CA 1.4 2013/03/17 16:30:31 35.051N 117.676W 0.0 6 km ( 4 mi) NNW of Boron, CA 1.1 2013/03/17 16:25:58 36.042N 117.799W 0.6 13 km ( 8 mi) E of Coso Junction, CA 0.6 2013/03/17 12:48:03 35.991N 117.917W 4.2 7 km ( 4 mi) SSE of Coso Junction, CA 0.2 2013/03/17 12:16:07 35.992N 117.925W 4.2 6 km ( 4 mi) SSE of Coso Junction, CA -0.2 2013/03/17 10:41:26 36.026N 117.802W 1.0 13 km ( 8 mi) E of Coso Junction, CA 0.9 2013/03/17 03:59:36 35.667N 118.457W 9.7 3 km ( 2 mi) NNE of town of Lake Isabella, CA 0.4 2013/03/16 22:35:06 36.030N 117.783W 2.6 15 km ( 9 mi) E of Coso Junction, CA 0.2 2013/03/16 22:20:07 35.839N 117.689W 6.1 24 km (15 mi) N of Ridgecrest, CA 0.3 2013/03/16 20:44:35 36.017N 117.811W 2.4 13 km ( 8 mi) ESE of Coso Junction, CA 0.2 2013/03/16 16:19:33 35.834N 117.686W 2.1 24 km (15 mi) N of Ridgecrest, CA 0.3 2013/03/16 11:45:29 36.080N 117.842W 2.3 10 km ( 6 mi) ENE of Coso Junction, CA 0.1 2013/03/16 10:15:31 36.049N 117.846W 2.3 9 km ( 6 mi) E of Coso Junction, CA 2.3 2013/03/16 08:18:41 35.780N 118.514W 6.3 16 km (10 mi) SE of Pine Flat, CA 0.2 2013/03/16 00:25:12 35.788N 118.035W 9.6 30 km (18 mi) SSW of Coso Junction, CA 1.4 2013/03/15 15:58:50 35.401N 118.714W 8.4 24 km (15 mi) NNE of Arvin, CA 0.4 2013/03/15 15:48:20 36.026N 117.764W 1.7 17 km (10 mi) E of Coso Junction, CA 1.9 2013/03/15 13:44:13 35.903N 118.971W 15.4 18 km (11 mi) SSE of Porterville, CA

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Data Sources

Northern California - USGS = U.S. Geological Survey, Menlo Park Northern California - UCB = University of California, Berkeley Southern California - USGS = U.S. Geological Survey, Pasadena Southern California - Caltech = California Institute of Technology Southern California - UCSD = University of California, San Diego Nevada - UNR = University of Nevada, Reno US and World - USGS/NEIC = National Earthquake Information Center Offshore = West Coast & Alaska Tsunami Warning Center ...all members of the Advanced National Seismic System (ANSS)

713 http://www.data.scec.org/recenteqs/Maps/118-36.html 3/22/2013 KRV 63896_65562_65590_67589 2

1 714 KRV 66170 1

715 KRV 66170 1

716 KRV 66170 1

717 KRV 66170 1

718 KRV 66170 1

719 KRV 66170 1

720 KRV 66170 1

721 KRV 66170 1

722 KRV 66170 1

723 KRV 66170 1

724 KRV 66170 2

725 KRV 66170 2

726 KRV 66170 2

727 KRV 66170 2

728 KRV 66170 2

729 KRV 66170 2

730 KRV 66170 3

NOTE: This publication is meant to be an aid to the staff of the CDPH Drinking Water Program and cannot be relied upon by the regulated community as the State of California 's representation of the law. The published codes are the only official representation of the law. Refer to the published codes-s-in this case, 17 CCR and 22 CCR-whenever specific citations are required Statutes related to CDPH's drinking water-related activities are in the Health & Safety Code, the Water Code, and other codes.

(1) If daily water usage data are available, identify the day with the highest usage during the past ten years to obtain MOD; determine the average hourly flow during MOD and multiply by a peaking factor of at least 1.5 to obtain the PHD. (2) If no daily water usage data are available and monthly water usage data are available: (A) Identify the month with the highest water usage (maximum month) during at least the most recent ten years of operation or, if the system has been operating for less than ten years, during its period of operation; (B) To calculate average daily usage during maximum month, divide the total water usage during the maximum month by the number of days in that month; and (C) To calculate the MOD, multiply the average daily usage by a peaking factor that is a minimum of 1.5; and (0) To calculate the PHD, determine the average hourly flow during MOD and multiply by a peaking factor that is a minimum of 1.5. (3) If only annual water usage data are available: (A) Identify the year with the highest water usage during at least the most recent ten years of operation or, if the system has been operating for less than ten years, during its years of operation; (B) To calculate the average daily use, divide the total annual water usage for the year with the highest use by 365 days; and (C) To calculate the MOD, multiply the average daily usage by a peaking factor of 2.25. (0) To calculate the PHD, determine the average hourly flow during MOD and multiply by a peaking factor that is a minimum of 1.5. (4) Ifno water usage data are available, utilize records from a system that is similar in size, elevation, climate, demography, residential property size, and metering to determine the average water usage per service connection. From the average water usage per service connection, calculate the average daily demand and follow the steps in paragraph (3) to calculate the MOD and PHD.

(c) Community water systems using only groundwater shall have a minimum of two approved sources before being granted an initial permit. The system shall be capable of meeting MOD with the highest-capacity source off line.

(d) A public water system shall determine the total capacity of its groundwater sources by summing the capacity of its individual active sources. Ifa source is influenced by concurrent operation of another source, the total capacity shall be reduced to account for such influence. Where the capacity of a source varies seasonally, it shall be determined at the time of MOD.

(e) The capacity of a well shall be determined from pumping data existing prior to March 9, 2008, or in accordance with subsection (f) or (g). Prior to.conducting a well capacity test pursuant to subsection (g), a system shall submit the.information listed below to the Department for review and approval. For well capacity tests conducted 203

Last updated June 21, 20l2-from Titles 17 and 22 California Code of Regulations California Regulations Related to Drinking Water

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