gmw.conservation.ca.gov€¦ · 25/07/1978 · state of california~ the resources· agency edmund...

'

t STATE OF CALIFORNIA- THE RESOURCES AGENCY

DEPARTMENT OF CONSERVATION

EDMUND G. BROWN JR., Governor

DIVISION OF MINES AND GEOLOGY SAN FRANCISCO DISTRICT OFFICE FERRY BUILDING

SAN FRANCISCO, CA 94111 (Phone 415-557 -0633)

January 16, 1979

Mr. Douglas W. Cole, Secretary City of San Bernardino Environmental Review Committee 300 North "D" Street San Bernardino, CA 92418

Dear Mr. Cole:

We are placing on open file the following report, reviewed and approved by the City of San Bernardino In compliance with the AlquistPriolo Special Studies Zones Act:

Engineering geology investigation, Parcels 1 and 2, "E" Street and Hunts Lane, San Bernardino, CA; by Rasmussen and .Assoc.; July 25, 1978.

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Sincerely yours,

EARL W. HART Office of the State Geologist CEG 935

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CIT RN ARDINO 300 NORTH "D" STREET. SAN BERNARDINO, CALIFORNIA 92418

W. R. "BOB" HOLCOMB Mayor

Members of the Common Council

Robert A. Castaneda . , ......... , First Ward Edward S. Wheeler,Jr. , .. , , ... . Second Ward William Katona ......... , .. , ... Third Ward Richard F. Gerwig ............ Fourth Ward Lionel E. Hudson .............. Fifth Ward John D. Hobbs ................ Sixth Ward Russell E. Lackner ........... Seventh Ward

Earl w. Hart Office of the State Geologist Division of Mines and Geology San Francisco District Office Ferry Building San Francisco, California 94111

Re: Filing of Geologic Report

Dear Mr. Hart:

January 12, 1979

Reference is made to your letter dated December 7, 1978 regarding non-receipt of a geologic report (Report No. 4) forwarded to your office on December 4, 1978. The applicable report and evaluation is attached for filing.

Please excuse the error.

Very truly yours,

V~w~ Douglas w. Cole, Secretary Environmental Review Committee

Attachment

STATE OF CALIFORNIA~ THE RESOURCES· AGENCY EDMUND G. BROWN JR., Governor


DIVISION OF MINES AND GEOlOGY SAN FRANCISCO DISTRICT OFFICE FERRY BUILDING

SAN FRANCISCO, CA 94111] {Phone ..S 1 S-557 ·0633)

'.1 ·:, :1~ ~

I De.cember 7, 1978

Mr. bouglas W. Cole City of San Bernardino 300 North D Street San Bernardino, CA 92418

Dear Mr. Cole:

This is to acknowledge receipt of your Jetter of December 4 and the reports submitt~d for flle in accordance'with the Alquist-Priolo Special Studies Zones Act. .1The reports received will be filed as required. '

I

It ls,noted ~hat one of the reports of Mr. Rasmussen and the evaluation 6f Dr. Williams was not received as indicated in your letter (report No. 4 on your list}. Please submit these materials so they may be fl 1 ed.

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Enc11osure

cc: A-P file

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, Sincerely yours,

\I EARL W. HART Office of the State Geologist CEG 935 ·

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Div. Mines and Geology Ferry Bldg. Attn: Mr. Hart

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12/4/78

Evaluated b0• Dr. F1oyd J. Williams, Registered Geologist No. 2143, dated February 18, 1978. ·

~vb. Tentative Tract No. 10262, between ·Hemlock Drive and Piedmont Drive, Gary S. Rasmussen, Engineering Geologist No. 925, dated June 20, 1978.

Evaluated by Dr. Floyd J. Will tams, Registe,red Geologist No. 2143, dated July 3, 1978. 1

, I . \

:-,, .. ' ( 4) Pdrcel~ 1 and 2, "t" Street and Hunts Lane, Gary S. Rasmussen, Engineering .---~ Geologist No. 925, dated July 25, 1978.

Evaluat<·d by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated August 11, 1978.

r 5. Lots 10 and 11, southwest corner of Waterman Avenue and 49th Street, Gary S. Rasmussen, Engineering Geologist l';lo. 925, dated September 25, 1978.

I

Evaluated ,by Dr. Floyd J.1 Williams, Registered Geologist No. 2143, dated November 8, 1978. 1

v 6. Minor Subdivision east of Genevieve· Street and south of 54th Street, Gary S. Rasmussen, Engineering Gedlogist No. 925, dated May 4, 1978.

Evaluat~d by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated May 17, 1978. . .

,. 7. Two lots, northwest corner Wa.terman Avenue and 49th Street, Gary S. Rilsmussen, Engineering Geologist No. 925, d~ted March 9, 1978,

I ...

I

Evaluated by Dr. Floyd J. 'Williams, Registered Geologist No. 2143, dated April 12, 1978. Ii '

8. Waterman apartment complex, Charles Price, Certified Engineering Geologist No .. 183, dated April 1978.,

. I

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated May 1, 1978. I

, •. 9. 8.7 acre site. Project No. 1403 (Rasmussen), Gary S. Rasmussen, Engineering Geologist No. 925, dated October 12, 1978.

1 Evaluated by Dr. Floyd J: Williams, Registered Geologist No. 2143, dated

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$TAT[ l'f C~\UFORNIA-THE RE50URCE$ AGENCY EDMUND G


DIVISION OF MINES AND GEOLOGY SAN FRANCISCO DISTRICT OFFICE FERRY BUILDING

SAN FRANCISCO, CA 94111

(Phone 415-SS7 ·0633)

December 7, 1978

Mr. Douglas W. Cole City of San Bernardino 300 North D Street San Bernardino, CA 92418

Dear Mr. Cole:

This is to acknowledge receipt of your letter of December 4 and the reports submitted for file in accordance with the Alquist-Priolo Special Studies Zones Act. The reports received will be filed as required.

It is noted that one of the reports of Mr. Rasmussen and the evaluation of Dr. Williams was not received as indicated in your letter (report No. 4 on your list). Please submit these materials so they rey be f i 1 ec.

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Enclosure

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Sincerely yours,

.. ·. ) -.; -k.. .1 (-~ 1: ..... '

EARL \.'. HART Office of the State Geologist CEG '?35

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CIT ERNARDINO 300NORTH "D" §TREET,SAN BERNARDINO.CALIFORNIA 92418

• iHE. ~.JI-'·'

W. R. "BOB" HOLCOMB Mayor

Members of the Common Council

Robert A. Castaneda ......•..... First Ward Edward S. Wheeler, Jr .......... Second Ward Wilnam Katona ....••••.•••...• Thi'd wa,d December 4. 1978 Richard F. Gerwig . , .. , ....... Fourth Ward Lionel E. Hudson ...••. · .••••..• Fifth Ward · John D. Hobbs .••..••.••••.... Sixth Ward Russell E. Lackner ........... Seventh Ward

Division of Mines and Geology Ferry Building San Francisco, CA 94111

Attention: Earl W. Hart

Dear Mr. Hart:

Pursuant to Section 2623 of the Alquist-Priolo Special Studies Zone Act, we are forwarding to you for filing the following geologic reports and evaluations:

·'· 1. Tentative Tract No. 10350, Gordon A. Clopine, Registered Geologist No. 511, dated March 26, 1978.

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated Apri 1 1, 1978.

Supplemental to Geologic/Seismic Report, Tract No. 10194, 10258, and 10259, vicinity North "F" Street and Louise Street, Gordon A. Clopine, Registered Geologist No. 511, dated March 19, 1978.

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated April 1, 1978.

Supplemental No. 2, north end of "H" and "F" Streets, Gordon A. Clopine, Registered Geologist No. 511, dated June 24, 1978.

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated July 13, 1978.

·(Note: The earlier reports, referred to above, on Tracts 10194, 10258, and 10259, together with evaluations by the City Geologist, were filed with your office on August 23, 1977.

3. a. Preliminary Investigation - 45 acre parcel, Piedmont and Manzanita, ~ Gary S. Rasmussen, Engineering Geologist No. 925, dated February 8, 1978.

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Div. Mines and Geology Ferry Bldg.

12/4/78

Attn: .. Mr .• Hart ...

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Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated February 18, 1978.

Tentative Tract No. 10262, between Hemlock Drive and Piedmont Drive, Gary S. Rasmussen, Engineering Geologist No. 925, dated June 20, 1978.

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated July 3, 1978 •

.x;4. Parcels 1 and 2, "t"· Street and Hunts Lane, Gary S. Rasmussen, Engineering Geologist No. 925, dated July 25, 1978.

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated August 11, 1978.

iX.. 5. Lots 10 and 11, southwest corner of Waterman Avenue and 49th Street, Gary S. Rasmussen, Engineering Geologist No. 925, dated September 25, 1978,

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated November 8, 1978.

I!\: 6. Minor Subdivision east of Genevieve Street and south of 54th Street, Gary S. Rasmussen, Engineering Geologist No. 925, dated May 4, 1978.

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated May 17, 1978.

•\ 7. Two lots, northwest corner Waterman Avenue and 49th Street, Gary S. Rasmussen, Engineering Geologist No. 925, dated March 9, 1978.

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated April 12, 1978.

,x 8. Waterman apartment complex, Charles Price, Certified Engineering Geologist No. 183, dated April 1978.

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated May 1, 1978.

v\ 9. 8.7 acre site. Project No. 1403 (Rasmussen), Gary S. Rasmussen, Engineering Geologist No. 925, dated October 12, 1978.

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated October 23, 1978.

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Div. Mines and Geology Ferry Bldg. Attn: Mr. Hart

12/4/78

~\ 10. 8.5 acre parcel - Northeast corner Arden and Mesquite Drive, Jerry D. Horne, Registered Geologist No. 547, dated May 20, 1978.

Evaluated by Dr. Floyd J. Williams, Registered Geologist No. 2143, dated July 13, 1978.

Should you have any questions regarding these reports please contact the Planning Department at (714)383-5057.

~~·~~ DOUGLAS W. COLE, Secretary Environmental Review Committee

DWC:fm enc

'' California License No. 2)43

FLOYD J. WILLIAMS REGISTERED GEOLOGIST

. TO I

FROM1

DATE1

MEMORANDUM

Environmental Rev<,ew Conunittee City of San Bernardino Attn 1 Mr, Douglas·. Cole

Floyd J, Williams, ~gistere<J.~~ol0gist,

August 11, 1978<...yt,_{/<~')l. J.. ;{,/?,,.~,,, ,.

130 Sunridge Way

Redlands, California 92373

1714) 792-8208

SUBJECT1 Evaluation of geological report pursuant to provisions ot' the Alquist-Priolo Special Studies Zones Act

TITIE OF REPORT1 Engineering geology investigation, Parcels 1 and 2, "E" Street and Hunts Lane, San Bernardino, California, Dated1 July 25, 1978,

GEOLOGIST WHO PREPARED AND SIGNED REPORT• Mr, Gerald J, Grimes, Staff Geologist Mr. Gary S, Rasmussen, EG 925, State of California

PROCEDURE USED IN EVALUATING REPORT 1

1. Read report, 2. Reviewed UCR publication, "Geological investigations

of the San Jacinto Fault Zone", September, 1973, edited by Elders.

3, Made site inspection.8/2/78,

CONCLUSIONS 1

1, The report adequately describes geologic conditions at the site, including a potential for differential settling, liquefaction, and possibly flooding,

2, The trace of the active San Jacinto fault-is believed to be located 200 to 500 feet SW of the SW corner of the property,

RECOMMENDATIONS 1

1, This report, meets the requirements of the AlquistPriolo Act

I I I I I I I I I I I I I I I I I I I

GARY S. RASMUSSEN & ASSOCIATES /ENGINEERING GEOLOGY

1906 SO. COMMERCENTER EAST, SUITE 207 • SAN BERNARDINO, CA 92.406 • (7t4J 888-2422 • (71.4) 825-9052

ENGINEERING GEOLOGY INVESTIGATION PARCELS 1 AND 2

"E" STREET AND HUNTS LANE SAN BERNARDINO, CALIFORNIA t,'!7

aP/~ July 25, 1978 r I Project No. 1371

Prepared for

G.W. Singletary 1834 Spruce Street

Riverside, California 92507

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GARY S. RASl>.ll:USSEN & ASSOCIATES /ENGINEERING GEOLOGY

1906 50. COMMERCENTER EAST, SUITE 207 • SAN BERNARDINO, CA 92-408 • (714) BBB-2422 • C714) 825-9052

July 25, 1978

G.W. Singletary 1834 Spruce Street Riverside, California 92507

Project No. 1371

Subject: Engineering Geology Investigation of Parcels 1-4 of Parcel Map 1455, SW Corner of "E" Street and Hunts Lane, San Bernardino, California.

A subsurface geology investigation of the site along the south side of

"E" Street, north of the I-10 freeway and west of Hunts Lane, has been

conducted ·at your request. The north property line is contiguous with

"E" Street. The dimensions of the property and the location of our sub

surface trench are shown on the 100-scale map on Enclosure 1. The purpose

of our investigation was to determine if any active faults pass through

the Special Studies Zone portion of the site in accordance with Alquist

Priolo Special Studies Zones Act requirements. A 60-scale parcel map,

prepared by Lockwood Engineering and Surveying Company, Inc., dated

November, 1977, was used for our investigation. We understand commercial

buildings will be built on the parcels. The site lies within a zone of

suspected active faults, as defi1Yed by the Alquist-Priolo Special Studies

Zones Act. The San Jacinto fault has been plotted as passing southwest

of the site as shown on the Special Studies Zone map by the State of

California. The location of the site and its relation to the Alquist

Priolo Special Studies Zone boundaries are shown on the index map on

page 2.

SITE INVESTIGATION

The site had been recently cleared at the time of our investigation. The

only vegetation on the surface of the site was a large cottonwood tree,

which is located at the west end of the site.


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San Bernardino, California

Legend

---···· Fault, dashed where approx., dotted where buried

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Limits of Special Studies Zone

Base tfap CDMG Special Studies Zones Hap 1973 1"=2000' scale

Pro·ect No. 1371

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Gary S. Rasmussen & Associates, Inc.

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G.W. Singletary-Parcels 1-4-San Bernardino July 25, 1978

Project No. 1371

The active San Jacinto fault zone is located in the vicinity. The main

fault traces of the San Jacinto fault zone are located southwest of the

site, based on lineations observed on aerial photographs, published maps

(CDMG, 1973, and Sieh, 1973), and damming of ground water by the fault.

All of the suspected active fault traces are northwest trending features

in this area; therefore, a single, long backhoe trench was excavated

across the Special Studies Zone portion of the site. The trench was

excavated in a manner that would intercept any northwest trending fault

parallel to the San Jacinto fault zone which would pass through the Special

Studies Zone portion of the parcel (Enclosure 1). The trench walls were

examined in detail for evidence of faulting, and none was found. The

trench log is enclosed with this report. Trenching was limited to the

Alquist-Priolo Special Studies Zone portion of the site, as no evidence

of faulting was found through the remainder of the site.

A geologic field reconnaissance of the site and surrounding area was

conducted during June, 1978. A single backhoe trench was excavated across

the Special Studies Zone portion of the site from the southwest corner in

an easterly direction adjacent to the south property line to a depth of

9 to 11 feet to determine if any active faults passed through the site

(the exact age of sediments at 11 feet is not known, but is estimated

to be of sufficient age to easily observe fault rupture along the very

active San Jacinto fault zone). In addition to the field work, our

investigation included review of stereoscopic aerial photographs flown

in 1938, 1953, and 1978; review of pertinent geologic literature and

seismic information including personal communication with other geologists

having knowledge of faulting in the area; review of our files on faulting

in the immediate vicinity; and review of significant seismic information

including recorded, historic earthquakes. A list of references is

enclosed.

-3-GARY S. RASMUSSEN & ASSOCIATES


G.W.Singletary-Parcels 1-4-San Bernardino July 25, 1978

SITE GEOLOGY

Project No. 1371

The site is located on Holocene alluvium within the southwesterly portion

of the San Bernardino Valley. The site is approximately l,SQQ feet south

of the Santa Ana River. The materials observed in the trenches were

apparently deposited during several different geologic environments, as

they range from very clean, coarse sands to clay and depo9its representa

tive of previous swamp conditions. The interbedded sands, silts and

clays indicate a significant amount of time is represented by the 9 to

11 feet of sediments exposed in the trench (see Trench Log, Enclosure 5).

The sediments encountered within the trench are all considered to be of

late Holocene in age and are alluvial sands, silts, and clays. The materials

observed in the trench were very well bedded in the west end of the trench,

becoming more massive to the east. The site is on a former flood plain

of the Santa Ana River. The site was a swampy, marshy area during the

late 18QO' s and early 190Q' s according to published maps (Mendenhall, 1905).

Artesian ground water conditions were common in this area until the mid-

1940' s (Dutcher & Garrett, 1963). The approximate location of geologic

units is shown on the geologic index map (Morton, 1974, Enclosure 2).

The site is located in the southwesterly portion of the San Bernardino

Valley, which is considered to be a subsiding block of land located east

of the relatively stable Perris Block (Fife, et.~ .• 1976). The northwest

boundary of the Perris Block is generally considered to be the Cucamonga

fault and base of the San Gabriel Mountains, whereas the northeasterly

boundary of the stable Perris Block or the westerly boundary of the sub

siding San Bernardino Block is generally considered to be the San Jacinto

fault, located approximately 20Q to SQQ.feet southwest of the site. An

apparent vegetational lineation can be seen in that area on the 1938 and

1953 aerial photographs.

-4-GARY S. RAS~USSEN & ASSOCIATES



Project No. 1371

Damming of ground water by the San Jacinto fault, which was referred to

as the Bunker Hill Dike in early geologic literature, resulted in swamp

conditions and a ground surface covered with water throughout the area

immediately northeast of the San Jacinto fault. This swamp or area of

surface water extended for nearly 2~ miles to the northeast in the early

1900' s (Mendenhall, 1905}. In addition, early wells northeast of the San

Jacinto fault in this same area were commonly artesian with significant

flows. Heavy pumping of the ground water table in the basin northeast

of the San Jacinto fault has resulted in a major lowering of the ground

water table in this area. Evidence of a previously high ground water

table was readily apparent in the trench walls on the site.

TRENCH LOGS

The trench for this investigation was 280 feet long and the sediment

grain size ranged from clayey silt to coarse sand. The upper 2 feet of

material through the entire length of the trench was fill material placed

on-site sometime after 1954. Prior to 1954, a residence existed on

the west end of the site and a commercial building existed on the east

end. Some remnants of the building appear to have been incorporated

into the fill. The material from 2 to 5 feet in depth in the trench

appeared to be a stream-deposited sand and exhibited good bedding and

cross-bedding. This deposit was probably deposited prior to the 1900's.

It is our opinion that this deposit is not part of the 1938 flood deposits,

as this site is not believed to have been inundated by that flood (observa

tion of 1938 photos taken after flood period}. The remainder of the trench

is interbedded sands and silts. A good sample of wood was obtained at

a depth of 8 feet in a silty fine sand layer; this wood had not been

carbonized, suggesting a relatively young age, but the possibility of

it being an old root system does exist.




Project No. 1371

An open fracture was found at station 102 at a depth of 5 feet. It was

associated with a fine sand that appeared to have liquefied and also a

vertical lenticular organic silt deposit. The silt deposit was below the

fracture and decay of the organics in it could have resulted in differen

tial settlement, causing the open fracture. Two other fractures were

observed at stations 136 and 146. There was a 1-mm flexure of sediments

on the crack at station 136; neither of these fractures continued to the

bottom of the trench. These three fractures are probably associated with

subsidence and/or liquefaction in the area. Near vertical flow structures

were apparent in the upper portion of the south side of the trench at

sections 88 to 98, indicating liquefaction of the upper sediments have

probably occurred at that location.

A previous investigation by this firm along the San Jacinto fault, farther

to the northwest along the east side of Lytle Creek, encountered fault

rupture at a depth of 6 feet which was covered by unfaulted coarse sand

of Lytle Creek. An investigation conducted by the University of California,

Riverside (Elders, 1973), resulted in trenching of the San Jacinto fault,

approximately J,, mile to the southeast. Their trenches encountered the

fault within 3 to 4 feet of the ground surface. The unbroken layer

just above the fault was dated by Carbon-14 analysis of fresh water

gastropods at 670 years B.P. but "this date may be greater than the actual

age of the gastropods since the shells may be partially composed of

'old' carbon taken up from the marsh water" (Elders, 1973 p. 30). Addi

tional trenching of the fualt within the Southern Pacific Railroad

right-of-way resulted in a Carbon-14 date of approximately 300 years at

a depth of 7 feet (Jeffrey R. Keaton, personal communication, 1976). It

can be inferred from the'preceding information that the fault in the area

of the present investigation should rupture sediments within the upper 6

feet of the surface and that the ground rupture in this area is relatively

young, equal to or less than 300 years; therefore, a trench to 10± feet in

this area should expose the fault if it passes through the Special Studies

Zone portion of the site.

-6-G.ARY S. RASMUSSEN & ASSOCIATES



Project No. 1371

Trenching of the sediments is consistent with the current state-of-the

art for investigating recency of faulting for the type of use intended

for the site. The site occupies a flood plain and is not located within

an active channel of any nearby drainages or rivers. No evidence of

faulting was found in the trench; therefore, the potential for fault

rupture through the site is considered to be very low to non-existent.

SEISMIC SETTING

The northwest trending, very active San Jacinto fault is located approxi

mately 200 to 500 feet southwest of the southwest corner of the site, based

on published literature (Sieh, 1973). The San Jacinto fault is considered

to be the most active fault in southern California. Numerous trenches

across the San Jacinto fault in the San Bernardino area reveal fault

rupture within a few feet of the surface within young alluvium (estimated

to be less than 200 years old). Therefore, the fault is considered to

be active, having undergone very recent and possibly historic surface

rupture.

Another branch of the San Jacinto fault zone is the Loma Linda fault,

located approximately 5,000 feet northeast of the site. The Loma Linda

fault is not known to have broken Holocene alluvium and has been defined

on the basis of ground water data. The Loma Linda fault is not considered

to be an active fault (does not rupture Holocene alluvium, Dutcher &

Garrett, 1963).

The active San Andreas fault is located approximately 6~ miles northeast.

Both the San Andreas and San Jacinto faults are characterized by right

lateral movement ..

Other active faults are located in the general region, such as the

Cucamonga and Elsinore faults, but because of their greater distance from

-7-GARY S. RASMUSSEN & .ASSOCIATES



Project No. 1371

the site and/or lower probability of producing a significant earthquake

during the life of the proposed structures, they are not considered

significant when compared to these two, nearby major faults.

A sununary of major faults and their distances from the site arc shown in

the following table:

FAULT

San Jacinto

San Andreas

Cucamonga

Chino-Elsinore

SEISMIC HISTORY

DISTANCE FROM SITE (MILES)

200 to 500 feet SW

6\ NE

12 NW

21 SW

Numerous earthquakes up to Richter magnitude 4.5 have occurred historically

in the vicinity and probably originated on the San Jacinto fault zone.

The location of epicenters is not precise enough to always correlate

earthquakes with certain faults. A Richter magnitude 5.5 earthquake

occurred approximately 13 miles northwest of the site in 1970, presumably

along the San Jacinto fault zone. Numerous earthquakes with Richter

magnitudes 6.0 to 7.0 have occurred along the length of the San Jacinto

fault between the San Gabriel Mountains and Mexico during historic times.

The 1923 earthquake, estimated at Richter magnitude 6.0 to 6.3, was

centered in the area south of Loma Linda (probably along the San Jacinto

fault zone within 10 miles of the site), and resulted in severe structural

damage to' buildings in San Bernardino and Redlands (CDWR, 1964, San

Bernardino Sun, July 24, 1923). In addition, significant earthquakes

occurred prior to instrumentation in the late 1800's and early 1900's,

some of which were estimated to have also been in the magnitude 6.0 to 6.5

range. Earthquakes of Richter magnitudes 6.0 to 7.0 have occurred

-8-GARY S. RASMUSSEN & ASSOC::~ATES



Project No. 1371

somewhere along the length of the San Jacinto fault on the average of

once every S to 6 years since 1890 (Lamar, et.~., 1973).

The San Andreas fault zone has been very quiet in southern California, from

a seismic standpoint, since the great Fort Tejon earthquake of 1857.

This fault has the characteristic of undergoing long periods of time with

no activity or movement (160~ years, Sieh, 1977), then suddenly releases

large amounts of energy, such as the 1906 San Francisco and 1857 Fort

Tejon earthquakes.

SEISMIC ANALYSIS

Significant earthquakes affecting the site are likely to occur on either

the San Jacinto or San Andreas fault during the life of the proposed

structures. Recurrence intervals for maximum probable earthquakes

cannot yet be precisely determined from a statistical standpoint, as

recorded information on seismic activity does not encompass a sufficient

span of time. However, based on information available at this time, it

is our opinion that the following maximum probable earthquakes should be

expected (at least SO percent chance of occurrence within the next 100

years); up to Richter magnitude 7.0 along the San Jacinto fault, and

magnitude 7.5 along the San Andreas fault. Larger earthquakes could

occur on these or other faults, but their probability of occurrence for

that time period is low.

An earthquake of Richter magnitude 7.0 along the San Jacinto fault should

be expected to produce maximum peak ground accelerations in bedrock under

the site of approximately O. 7g (bedrock under the site is estimated to be

more than 800 feet deep, Fife, 1976). This acceleration should not be

used as a design value as it is a maximum peak acceleration and should

only be regard.ed as an aid in the evaluation of the structural design

of buildings to be placed on the site.




Project No. 1371

Large earthquakes may occur on other faults not mentioned, but they are

considered less significant to the site because of their larger distance

or lower probability of occurrence.

GROUND WATER

As previously mentioned, ground water occurred at the surface in the

early 1900's in this area, and artesian conditions occurred for wells placed

northeast of the San Jacinto fault (previously referred to in early

literature as the Bunker Hill Dike, L.C. Dutcher & A.A. Garrett, 1963,

Mendenhall, 1905). The valley or basin northeast of the San Jacinto

fault is generally confined by the San Jacinto fault on the west, the

mountains on the north, and bedrock hills on the south and east. This

basin has been heavily pumped for agricultural and domestic use and has

had a generally deepening ground water table since the 1940's.

The depth to ground water in this area is variable, depending on previous

rainfall and importation of water. No ground water was encountered

during our trenching operations, but trenching operations taking place at

the same time approximately Y, mile southeast encountered high water table

conditions (approximately 7-8 feet below the ground surface).

Ground water information was obtained from the San Bernardino Valley

Municipal Water District for wells approximately 400 feet and 1,200 feet

north of the site. The depth to ground water on May 5, 1978 was 32

feet and 44 feet respectively. This is approximately a 100-foot rise in

the ground water table since February, 1977 (SBVMWD, 1977). Liquefaction

could be a potential problem with any additional rise in the water table.

Liquefaction has previously taken place in this area as previously

described under Trench Logs.


I I I

•• I I I I I I I I I I I I I I I


SUBSIDENCE

Project No. 1371

Regional subsidence has occurred east of the San Jacinto fault. The

largest amount of subsidence has occurred approximately 1 mile east of

the site. Subsidence of the ground surface is currently occurring on a

regional basis and will probably continue as long as excessive water is

pumped from the confined ground water basin. An open fissure approxi

mately 3-5 mm wide was observed in our trench wall. Some of this cracking

could be caused by decomposition of organic materials below the open

fissure. Because of the open fissure and the variability of the water

table in this area, subsidence cracking or fissuring is a potential hazard

and should be considered in the design of any buildings to be placed on

the site. Additional, thicker organic deposits are likely to exist at

depth under the site due to the previous_ long history of swamp conditions

in this area.

FLOODING

The technical report for the Seismic Safety Element to the San Bernardino

County General Plan indicates the site is within the 100-year flood

plain and, therefore, flooding is a potential hazard.

SLOPE FAILURE

An approximate l~ horizontal to 1 vertical, 20-foot-high fill slope exists

immediately south of the site. This slope is part of the Interstate 10

freeway which is located in this area, and it exists along the entire

length of the south property boundary. There is a possibility of slope

failure on this slope.

Earthquake induced, out-of-control, high-speed vehicles may possibly leave

the pavement of Interstate 10 and collide with the proposed structures.




CONCLUSIONS

Project No. 1371

The site is located approximately 200 to 500 feet northeast of the active

San Jacinto fault. No evidence of active faulting through the site was

found in our trench and other portions of our investigation, and grourid

rupture through the site from faulting is not expected.

Previous evidence of liquefaction on the site was observed in the trench.

Ground water conditions have changed drastically since the early portion

of the century, and the current depth to ground water of 32 to 44 feet

is generally considered to be below the depth at which liquefaction will

occur at the surface, but an additional rise in the water table could put

the ground water depth within the zone at which liquefaction can occur.

Subsidence cracking or differential settlement is likely on the site as

indicated by an open fissure in the westerly portion of the trench.

Severe seismic shaking of the site should be expected within the next

100 years.

Earthquake induced landslides are not expected to be a hazard as the site

is s·ufficiently far from natural steep slopes. There is a possibility of

slope failure along the 20-foot-high slope constructed for I-10. This

slope is approximately l~ horizontal to 1 vertical and the toe of the slope

is within 5 feet of the south property line and runs along its entire

length.

Earthquake induced flooding of the site is not likely as there are no

bodies of water or reservoirs immediately above the site that would

flood the site.

The site is located 1,500 feet south of the Santa Ana River and occupies

a former flood plain. Extensive concrete-lined flood control channels




Project No. 1371

have been placed along the Santa Ana River in the early 1970's, which

should help mitigate the flood hazard.

RECOMMENDATIONS

A maximum probable earthquake of Richter magnitude 7.0 is expected along

the San Jacinto fault in this area; therefore, we recommend human occupancy

structures be designed accordingly.

Subsidence cracking and/or differential settlement is possible on the

site and should be mitigated for by proper engineering design.

Liquefaction is a potential problem on the site due to the shallow

depth to ground water (approximately 32 feet) and the high ground

accelerations expected on the site. The final liquefaction potential

should be determined by the Soils Engineer, based on soils criteria.

GJG:GSR/mt

Enclosure 1: Enclosure 2: Enclosure 3: Enclosure 4: Enclosure 5: Distribution:

Respectfully submitted,

GARY S. RASMUSSEN & ASSOCIATES, INC.

c6~~c:t~

100-scale map Geologic index map References Alquist-Priolo data Trench log

Lockwood Engineering G.W. Singletary (4)

-13-

Gerald J. Grimes Staff Geologist

.//)~:!1/~.r~ Gary S. Rasmussen Engineering Geologist, EG 925

(4)

GARY S. RASMUSSEN & ASSOCIATES

-------------------

\

\

Trench 1

\ \

\

~-(\-

I , "E" Street

on-"ramp

SW limit of subsurface investigation, limited to area within property boundary

+ C Pxoperty boundary

·~NC limi< of subsurface ~Property investigation

NE limit of Special Studies Zone

U.S. Interstate Route No. 10

· ENCLOSURE 1 GARY S. RASMUSSEN & ASSOCIATES INC.

Project No. 1371

---boundary

1"=100'

\ I

Hunts---\

Lane \

I I· I I I I I I I I I I I I I I I I I

ENCLOSURE 2 Geologic Index Map

G.W. Singletary San Bernardino, California

Qar

Qasa

Qal

Qao

Tst

------··1

•••

Legend

Active river channel alluvium Santa Ana River channel alluvium Younger alluvium undifferentiated Older alluvium undifferentiated San Timoteo Beds, nonmarine conglomerate and sandy sediment Contact, dashed where approx. Fault, dashed where approx., dotted where concealed, queried where questionable Approx. location of fault inferred from seismic activity

Base /.lap CD!1G SR ll3 Scale 1"=4000'

Project No. 1371

;·

Gary S. Rasmussen & Associates, Inc. . .


REFERENCES

Allen, C.R., Saint Amand, P., Richter, C.F., and Nordquist, J.M., 1965, Relationship between seismicity and geologic structure in the southern California region: Seismological Society of America Bulletin, v. 55, no. 4, p. 753-797.

California Department of Water Resources, 1970, Meeting water demands in the Bunker Hill-San Timoteo area: Department of Water Resources Bulletin 104-5.

California Department of Water Resources, 1964, Crustal strain and fault movement investigation-Faults and earthquakes in California: Department of Water Resources Bulletin 116-2.

Dibblee, T.W., Jr., 1970, Regional geologic map of the San Andreas and related faults in eastern San Gabriel Mountains, San Bernardino Mountains, western San Jacinto Mountains and vicinity, Los Angeles, San Bernardino and Riverside Counties, Califmrnia: U.S. Geological Survey Open-file Rpt.

Dibblee, T.W., Jr., 1971, Geologic environment and tectonic development of the San Bernardino Mountains, California: Geological Society of America Abstracts with Programs, v. 3, no. 2, p. 109-110.

Dibblee, T.W., Jr., 1975, Late Quaternary uplift of the San Bernardino Mountains on the San Andreas and related faults, in Crowell, J.C., ed., 1975, San Andreas fault in southern California, a-guide to San Andreas fault from Mexico to Carrizo Plain: California Division of Mines and Geology Special Report 118, p. 127-135.

Dutcher, L.C., and Garrett, A.A., 1963, Geologic and hydrologic features of the San Bernardino area, California, with special reference to underflow across the San Jacinto fault: U.S. Geological Survey Water Supply Paper 1419.

Elders, W.A., 1973, Geological investigations of the San Jacinto fault zone and aspects of the socio-economic impact of earthquakes in the RiversideSan Bernardino area, California: University of California, Riverside Campus Museum Contributions Number 3, September 1973.

Fife, D.L., et.al., County, California: Report ll 3.

1976, Geologic hazards in southwestern San Bernardino California ~ivision of Mines and Geology Special

Friedman, M.E., Whitcomb, J.H., Allen, C.R., and Hileman, J.A., 1976, Seismicity of the southern California region, 1 Jan. 1972 to 31 Dec. 1974, Seismological Lab., California Inst. Technology.

i GARY S. RASMUSSEN & ASSOCIATES


Gosling, A.W., 1967, Patterns of subsurface flow in the Bloomington-Colton, Upper Santa Ana Valley, California: U.S. Geological Survey Hydrologic Investigations Atlas, HA-268 1:24,000.

Greensfelder, R.W., 1972, Crustal movement investigations in California: Their history, data, and signficcance: California Division of Mines & Geology Special Publication 37.

Greensfelder, R.W., 1974, Maximum credible rock acceleration from earthquakes in California: California Division of Mines and Geology Map Sheet 23.

Hileman, J.A., Allen, C.R., Nordquist, J.M., 1974, Seismicity of the southern California region, 1 January 1932 to 31 December 1972: Seismal. Laboratory, California Institute of Technology, Pasadena, CA, 404p.

Keaton, J.R., personal communication, 1976.

Jennings, C.W., 1975, Fault map of California with locations of volcanoes, thermal springs, and thermal wells: CDMG, 1:750,000.

Lamar, D.L., Merifield, P.M., and Proctor, R.J., 1973, Earthquake recurrence intervals on major faults in southern California, in Moran, D.E. and others, eds., 1973, Geology, seismicity and environmental impact: Association of Engineering Geologists Special Publication, p. 265-276.

Lofgren, B.E., 1971, Estimated subsidence in the Chino-Riverside-Bunker Hill-Yucaipa areas in southern California for a postulated water level lowering, 1965-2015, U.S. Geological Survey Open-file Report, Water Resources Division.

Mendenhall, W.C., 1905, The hydrology of San Bernardino Valley California: U.S. Geological Survey Water Supply Paper 142 and 219.

Miller, R.E., and Singer, J.A., 1971, Subsidence in the Bunker Hill-San Timoteo area, southern California: U.S. Geological Survey Open-file Report.

Moreland, J.A., 1972, Artificial recharge in the Upper Santa Ana Valley, southern California: U.S. Geological Survey Open-file Report.

Morton, D.M., 1975, Relations between major faults, eastern San Gabriel Mountains, southern California in Abstracts with programs. Cordilleran section, 7lst Annual Meeting, Geological Society of America, p. 352~353.

National Aeronautics and Space Administration, March 14, 1974, Color infrared. aerial photographs, Mission 74-041, 7590, 7591, Scale 1: 125, 000.

Rogers, T.H., 1967, Geologic map of California, Olaf P. Jenkins edition San Bernardino Sheet: California Division of Mines and Geology, 1:250,000.

ii GARY S. RASMUSSEN & ASSOCIATES


San Bernardino County Flood Control District, January 21, 1978, Aerial photographs, Flight C-279, Photos 88, 89, 90, l"=approx. 2,000 1 •

San Bernardino County, 1974, Seismic and public safety element of the San Bernardino General Plan.

San Bernardino Valley Municipal Water District, 1977, Upper Santa Ana Valley Cooperative Well Measuring program, Spring, 1977, Report No. Eng-77-E2.

San Bernardino Valley Municipal Water District, 1978, personal communication.

Schanbel, P.B., and Seed, H.B., 1973, Accelerations in rock for earthquakes in the western United States: Seismological Society of America Bulletin v. 63, no. 2.

Seed, H.B., and Idriss, I.M., soil liquefaction potential: Division, American Society of

1971, Simplified procedure for evaluating Journal of Soil Mechanics and Foundation Civil Engineers, v. 97, no. SM9.

Sharp, R.V., 1972, Map showing recently active breaks along the San Jacinto fault zone between the San Bernardino area and Borrego Valley, California: U.S. Geological Survey Miscellaneous Investigations Map I-675.

Sharp, R.V., 1975, En echelon fault patterns of the San Jacinto fault zone in Crowell, J.C., ed., 1975, San Andreas fault in southern California, aguide to San Andreas fault from Mexico to Carrizo Plain: California Division of Mines and Geology Special Report 118, p. 147-152.

Sidler, W.A., 1973, the Great flood of January 22, 1862: San Bernardino County Museum Association Quarterly, v. XXI, nos. 1 and 2, p. 6-20.

Sieh, K., et.al., 1973, Geological investigations of portions of the San Jacinto fault-Zone, San Bernardino, California, in Elders, W.A., Editor, Geological investigations of the San Jacinto fault zone, and aspects of the socio-economic impact of earthquakes in the Riverside-San Bernardino area, California: University of California, Riverside Campus Museum Contributions #3, PP. 1-46.

Sieh, K., 1977, PHD thesis.

Troxell, H.C., and others, 1942, Floods of March 1938, in southern California: U.S. Geological Survey Water Supply Paper 844.

United States Department of Agriculture, July 4, 1938, Aerial photographs, AXM/AXL-61-25, 26, l"=approx. 1700'.

United States Department of Agriculture, January 23, 1953, Aerial photographs, AXL 30k, 47, 48, 60, 61.

iii GARY S. RASMUSSEN & ASSOCIATES


Wallace, R. E., 1970, Earthquake recurrence intervals on the San Andreas fault: Geological Society of America Bulletin, v. 81, p. 2875-2889.

Willingham, C.R., 1968, A gravity survey of the San Bernardino Valley, southern California: unpublished M.A. thesis, University of California, Riverside, California.

iv GARY S. RASMUSSEN & ASSOCIATES


4 CALIFORNIA DIVISION OF MINES AND GEOLOGY SP 42

CALIFORNIA DIVISION OF MINES AND GEOLOGY PROGRAM FOR ZONING POTENTIALLY ACTIVE FAULTS

Requirements of the Act

The Alquist-Priolo Special Studies Zones Act of 1972 (codified as Chapter 7.5, Division 2, of the California Public Resources Code) requires the State Geologist to

1 .. "Delineate, by December 31, 1973, appropriately wide special studies zones to encompass all potentially and recently ac1ive traces of the San Andreas, Calaveras, Hayward, and San Jacinto Faults. and such other faults ... that ... consti1ute a potential hazard to structures from surface faulting or fault creep".

2. Compile maps of special studies zones and submit such maps to affected cities, counties. and state agencies by 31 December 1973, for their review and comment. Following appropriate reviews, the State Geologist must provide "official maps" to the affected cities. counties, and state agencies.

~

The State Geologist also is required to .. continually review new geologic and seismic data" in order to revise the special studies zones or delinCate additional zones.

The Act also requires Cities and Counties to exercise specified approval authority \vith respect to real estate developn1ent or structures for human occupancy v•ithin the special studies zones. Further it requires specific Policies and Criteria to assist local jurisdictions in administering the Act from the State Mining and Geology Board.

Program for Zoning Potentially Active Faults

As required under the Act, the State Geologist (Chief of the California Division of Mines and Geology) established a program starting early in 1973 to delineate special studies zones to encompass traces of potentially and recently active faults in California and to cori1pile and distribute niaps of these zones. A project team, headed by this \vriter, ,1.-·as established within the Division to develop a program for delineation of the zones.

Initially, 175 maps of special studies zones were compiled for the San Andreas, Calaveras, Hayward, and San Jacinto faults. These zone_ maps, issued as Preliminary R~view Maps, \1.-'erc distributed for review by local and State government agencies on December 31, 1973. Following needed revisions as prescribed by law, Official Maps were issued on July I, 1974. At that tin1e 1 the special studies zones became effective and implementation \vas >equired by the affected Cities and Counties:

A second set of zone maps 'vas issued subsequently to delineate new and revised zones--Preliminary Review Maps on July I, 1975, and Official Maps on January I, 1976. Zones delineated as part of this second issue.are sho\l,'n on about 81 maps of new zones and 5 maps of revised zones. It is expected that additional Official

Maps of new and revised zones \viii be issued each year on January 1 following issuance of a Preliminary Review Map on July 1 of the preceding year.

As of January I, 1976, approximately 256 Official Maps of special studies zones have been issued and presently are .in effect. These maps are identified by name on the Index to Maps of Special Studies Zones. The maps delineate zones for those faults identified in figure 1. Approximately 23 Counties and 58 Cities are affected by the existing special studies zones. These Counties and Cities are listed elsewhere in this report.

Faults zoned to date by the State Geologist are identified on figure I. Additional faults to be zoned in the near future include the Sierra Madre, Cuca1nonga, Raymond Hill, and Elsinore faults in southern California. There are many other faults in California that are potentially active (Jennings, 1973), and some of these may be zoned if determined to be "sufficiently active and well-defined as to constitute a hazard" (Chapter 2622 of the Act). As in the past, future zoning will be done on a priority basis depending on the availability of both data and funds.

Delineating the Special Studies Zones

Special st.udies zones are delineated on topographic base maps at a scale of 1 :24,000 (I inch equals 2000 feet). The zone boundaries are straight-line scgn1ents defined by turning points. Most of the turning points are intended to coincide with locatable features on the ground (e.g., bench marks, roads, streams), but neither these points nor the zone boundary lines between them have been surveyed in the field to verify their mapped locations.

The intent of the Alquist-Priolo Act is to' provide for public safety from the hazard of fault rupture by avoiding, to the extent possible, the construction of structures for hu111an occupancy astride hazardous faults. The faults shown on the special studies zone maps are not precisely located on the n1aps, nor were they surveyed in the field during this study. Their locations were taken from the best geologic maps and reports available, and plotted according to the best judgment and skill of the California Division of Mines and Geology's staff geologist-compilers. The precise location and identification of hazardous faults within or near a zone of potentially active faults can be detern1ined only through detailed geologic site investigations. Thus, this Act establishes the concept of a special studies zone-an area of limited extent centered on recognized faults-within which the danger of potential fault rupture is presumed· to exist until shO\\-'n otherwise by direct investigation. Poten1ially active faults other than those depicted on the maps, including branches and spurs of the named faults, may be present within the special studies zones. The zone boundaries delimit


6 CALIFORNIA DIVISION OF MINES AND GEOLOGY SP 42

the area believed by the State Geologist to warrant. special geologic investigations to confirm the presence or absence of hazardous faults.

Locations of special studies zone boundaries are controlled by the position of the known traces of potentially active faults (defined below). However, the faults shown on the special studies zones maps were not field checked during the compilation of these maps. Because available fault data range widely in quality, and the locations of some faults are known imprecisely, the zone b9undaries are positioned at a reasonable distance (about 660 feet, or 1/8 mile) on both sides of the trace of the nearest potentially active fault. However, zone boundaries generally are more or less than 660 feet away from mapped faults because of I) curved or multiple fault traces, 2) the practical advantage in keeping the number of turning points .to a reasonable minimum, and 3) the quality of the data dictates a narrower or wider zone.

Definitions

Fault and Fault Zone

A fault is defined as a fracture or zone of closely associated fractures along which rocks on one side have been displaced with respect to those on the other side. Most faults are the result of repeated displacement which may have taken place suddenly and/or by slow creep. A fault zone is a zone of related faults which commonly are braided and subparallel, but may be branching and divergent. A fault zone has s_ig_nificant width (with respect to the scale at which the fault is being considered, portrayed, or investigated), ranging from a few feet to several miles.

Fault Trace I

A fault trace is the line formed by the intersection of a fa41t and the earth's.surface. It is the representation ofa fault as depicted on a map, including maps of the special studies zones.

Potentially Active Fault

For the purposes of delineating special studies zones, any fault considered to have been active during Quaternary time (last 2 to 3 million years, figure 2}-on the basis of evidence of surface displacement-is considered by the State Geologist to be potentially active. An exception is a Quaternary fault which is determined, from direct evidence, to have become inactive before Holocene time (approximately the last 11,000 years). Such faults are presumed to be essentially inactive and most have been omitted from the maps. Although potentially active faults shown on .the maps may have been active during any part of, or throughout, Quaternary time, evidence for their recency of displacement commonly is incompletely preserved or equivocal.I In contrast, the State Mining and Geology Board, in their Policies and Criteria (adopted 21 November 1973), defined only those faults which have had surface displacement within Holocene time as "active and hence as constituting a potential hazard."

1 In those cases where data are available from field and aerial photographic investigations specifically directed at the problem of potential surface faulting, the potentially active faults shown on the special studies zones maps may not be directly relatable to the entire Quaternary Period. For example, the "recently active" fault traces depicted on some U.S. Geological Survey maps are believed to be predominantly of la1e Quaternary age and may exclude most faults that have become inactive during or prior to early Quaternary time.

. GEOLOGIC AGE YEARS BEFORE

faa Period Epoch

··Historic~

Holocene

QUATERNARY

u 0 Pleistocene

" 0 z t'l

Pliocene TERTIARY

PRESENT (estimated)

200

11.000

2.000.000 - 3.000.000-

7,000.000 - 10.000.000-

}

Faults along which movement has occurred during this interval are defined as acrive b)' Policies and Criteria o1 the State Min;ng and Geology Board.

Fau11s defined as poren!ialfy active for 1he pur· p:ise of delineating special ~ludies zones.

pre-Pliocene b5.000.000

pre-CENOZOIC time

---i Beginning ur i;(ufogic 1in1e : I 4,()00.000.000 1--

Figure 2. Geologic time scale

I I I I I I I I I I I I

197(> FAULT HAZARD ZONES IN CALIFORNIA 7

Uses and Limitations of Special Studies Zones Maps

The special studies zones are delineated to define those areas \vithin which special studies arc required prior lo building structures for hun1an occupancy. Traces of potentially active faults arc shov.:n on the 1naps n1ainly to justify the locations of zone boundaries. These fault traces are plotted as accurately as the sources of data pern1it; yet the 'plots are not sufficiently ;.1ccuratc to be used as the bases for set-back requiren1ents. and they should not be so used.

The State Geologist has identified potentially active faults in a broad sense. and the evidence for potential activity of son1c faults n1ay be only weak or indirect.

The fault inforn1ation shown on the 1naps is not s'ufficicnt 10 n1ee1 the requirefflent for special studies. Local govern111ental units n1ust require the developer to evaluate specific sites within the special studies zones to determine ifa potential hazard from any fault, whether

herelofore recognize;d or not, exists with regard to proposed structures and their occupants.

The surface fault ruptures associated with historic earthquake and creep events are identified where kno\vn. H cl\vcver, no degree of relative potential for future surface displacen1cnt or degree of hazard is i1nplied for the faults sh<)\vn. Surface ruptures resulting fron1 the secondary effects of scisn1ic shaking during historic tin1e are 0111itted fro111 the 111ap and do not serve as a basis for zoning.

Model Ordinance and Code

In order lo assist the cities and the counties to in1plement the Alquist-Priolo Act, a suggested Model Ordinance and Code was v•ritten by Ja1nes E. Slosson, forn1er State Geologist. This publication is available fron1 the Division of Mines and Geology, P.O. Box 2980, Sacramento CA 95812, for 25 cents plus tax.

SUMMARY OF POLICIES AND CRITERIA PURSUANT TO THE ACT

Policies and Crlteria, callccJ for in the A!quist-Priolo Act, were intially adopted on November 21, 1973, by the State M Lning and Geology Board follcHving a revie\v by all counties and incorporated cities in California. The Policies and Criteria were subsequently expanded and slightly revised July I, 1974, and June 26. 1975. Future revisions niay be anticipated in order to assist the cities and counties in i1nple111enting the Act.

I Table 2. A summary of policies and criteria adopted by the State Mining and Geology Board. Complete text is in Appendix B.

I I I I I I

P<>LICI ES

"l SUgg1..··as 11h:th11ds n.:l;iting to fl.'\ ii.'" 11f PrL·li1ni11;tr) Map" pri11r 1t1 is-.uani:"' uf (Jffii..:i;d M;1ps.

:\. P11lkks ;ind i..:ritL'ria appl) nnl) \u ar1..·a ''ithin 1hl' <ipL·o.:ial s1udi.._., 111111.·s.

-I. DL'lini.:-s .w1ii·c 1;111f1 (..;"4u:1h pnh:111i;d h:i1;1nl) a:-. a fault 1hat h•t~ had !'iurfao.:i..: disph11..'.L'111.:111 during Hnlui..:~111.' (ill1l' (f;1:-.1 11.000 ~i:;ir:-.).

.

I. N11 s1ru1.:1ur..:"> tor hu111;111 "l..'.L'UJl<lllL') arl· p<.:r111illl'd 1111 lliL' lf<KL'

of all <tt:li\L' /~1UI(. (l:n/...·~.; proVL'll 11!hcn1iS1.'. lhl' arL·;i \\ithin )(I

l\:l'I nl" all <h:livl· f;iu\t j~ j11"L'\UllH.'d lo hL' Ulld1.:rl;1i11 h) <Ill <lt:livc fault}.

R..:~uirc., ,gt·olo_gi1._· n:por! dir1.·L·11.·d at 1hi: pr<>hk111 of p<111.'nlial :-.urf;ii..:..:- f<iuhing fnr <ill pr11jL'l'.I\ tkrini..:d h) 1h.: Acl (SL'i..:1i"n ~fl~ l.h>.

J. Hcquirl'.'> iha1 gL•ol"gk l"L'por\'> hi..: pl;1i..:c1.I ull "P<.:ll lik hy thl.' S1;1\L' (iL·nli 1gi'l.

-L ki..:4uirl.':o. ..:ilk~ ;111d i..:nun1k' In fL'\ iL'I\ atk4u<K) of g..:olngii..: ri:pc>rt:-. suhn1illl'1.I ''ilh rL·l(uL'">l~ f,,r 1.k·,i.:-l1•pt11L'lll p..:r1ni1s.

5. Pl·rmi1, 1.:iti..:-. .1111.I i:ountil'-. tu i..:~1;1hli\h ">li111d.in!.. 111urc rc ... iricti\L. d1:1111h..: p••li..:iL·, ;ind ..:ri1L·ri;1.

h. D..:fin..: ... t•l) .. pr11jL'L'I ... ihl \\fui..:tur.: for huuian •1i..:o.:uri;11H.~·. :11H1 lo.:) llL.\\ rL·;il L"\lOLIL' tk\L·li·rmi..:111. .

ENCLOSURE 5 ----- --- ---- ------ -·-rtort-z-oni:-n--s-caie-r"=l-W .------Logged by JG TRENCH NO. 1

Vertical scale

------------ -- ------ --- --------------- ----

G~Y S.R~SMUSSEN & ASSOCIATES, INC. G. IV. Singletary Project No. 1371

I I I I I I I I I I I I I I I I I I

5

10

roP Foor ong, G,/I~ P£5 00>J4/ i<llRD n DllhlP

OllK. 611!J- SOJ-S 11..r, />!I CAu:ous,

N85W

100 f.T. /JI? .r/. S !' J..T!f F. - M. SO.

rregular gray silt bleb "'/ oRl/Al"1£ sr1111111119 _ See Trench Log for south side of trench

150 TRENCH NO. 1 200 250

0-b.:-:s~~-::0?::-:~~~~~~~::?""Dii'Z~:::::-?~~~~~:"?~~r..:.57:=-~~~~~~~~~~~~~=c::-::c=~,...,.J 280

0

5 5

•4 g."tARl//, .. I:. -~C. ~:':so ... -.:: lO_t-~'"~'c~-~-:~-.._~,,~,-~--~.,i··~ci·~~·~w~·~.,~s~-~~~-,~-~-~~-~~~~~~~~~~~~~~~~~~~_::1t;_~~~~;:~~{t~Si:jj'.J:1l~~[i~[f'.~fi:t:~~~~~:::t:'.:J~::IJ~~~~~~~~~ffl~~~

... ~ ...• .r.•- •• ··~ ....... -._ -~~. ~ ••.•. ---- -::.== - .•. ,j/() tJ - f'()I? ous

10

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JIOTTteJJ <"7Rtf F. -,n.

so.

10

gmw.conservation.ca.gov€¦ · 25/07/1978 · state of california~ the resources· agency edmund...

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