Developing an Earthquake Mitigation Program

7/29/2019 Developing an Earthquake Mitigation Program

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2003 by CRC Press LLC

34Developingan EarthquakeMitigation Program

34.1 Introduction34.2 Overview of an Earthquake Mitigation Program34.3 Phase 0: Pre-Program Activities34.4 Phase 1: Assessing the Problem34.5 Phase 2: Developing the Program34.6 Phase 3: Implementing the Program

Retaining Seismic Retrofit Design Professionals Funding the

Program Coordinating with Other Parts of the Organization

Perform Seismic Retrofit Dealing with Residual Risk

34.7 Maintaining the ProgramDefining Terms

ReferencesFurther Reading

When schemes are laid in advance, it is surprising how often the circumstances fit in with them.

Sir William Osler (18491919)

34.1 Introduction

Previous chapters of this volume have discussed the effects of earthquake and the potential resulting

damage. This chapter provides guidance on how to go about developing and implementing an earthquake

risk reduction program to reduce that potential damage that is, this chapter discusses developing an

earthquake mitigation program. An earthquake mitigation program has five basic aspects:

1. Pre-program activities

2. Assessing the risk

3. Developing the program

4. Implementing the program

5. Maintaining the program

The next section first provides an overview of these aspects, and is then followed by sections providinga detailed discussion of each aspect.

Charles ScawthornConsulting Engineer

Berkeley, CA


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34.2 Overview of an Earthquake Mitigation Program

Earthquakes are a problem and, in the most general sense, solving a problem has three basic phases:

1. Phase 1: Understanding the problem

2. Phase 2: Finding a solution3. Phase 3: Putting the solution into effect

Solving the earthquake problem that is, an earthquake mitigation program has these three basic

phases, plus two more phases. These two additional phases are required because earthquake mitigation

typically involves activities in large organizations over a prolonged period (years, if not decades), during

which personnel changes are not uncommon. Therefore, the two additional phases are (1) a phase zero,

which consists of actually getting a large organization to embark on an earthquake mitigation program,

and (2) phase 4: putting in place the organizational mechanisms such that the earthquake mitigation

program is maintained over the required period.

Regarding the latter phase, maintaining the earthquake mitigation program over the required period

is not actually sufficient; once the formal earthquake mitigation program has been completed, or duringits implementation, conditions are likely to change such that the earthquake mitigation program should

likewise change. Lastly, part of any comprehensive earthquake mitigation program is an emergency plan.

As discussed inChapter 33, maintaining an emergency plan is integral to that plan. Therefore, in the

sense that the emergency plan is part of the earthquake implementation program, and that the program

needs to be alert to changing conditions in the organization that may increase earthquake risk, mainte-

nance of the earthquake mitigation program is an ongoing task which never ends. That is, once the

formal earthquake mitigation program has been completed, earthquake mitigation should be an ongoing

part of the organizations normal risk management activities. Therefore, developing an earthquake

mitigation program involves the following five phases:

1. Phase 0, pre-program activities, involving increasing awareness of the potential earthquake prob-lem, and gaining authorization for an initial assessment of the problem.

2. Phase 1, assessing the risk, consisting of an initial review of life, property, and business or functional

exposures, and the threat that earthquakes may pose to them, in order to determine the current

seismic risk. That is, are earthquakes indeed a problem (i.e., does a problem exist?) and, if so,

what is the magnitude and nature of that problem?

3. Phase 2, developing the program, which consists of determining the organizations acceptable risk,

the options that exist for reducing the current risk to an acceptable level, the costs of doing that,

and how it should be accomplished.

4. Phase 3, implementing the program that is, actually taking the actions that reduce the risk.

5. Phase 4, maintaining the program so that the risk does not become unacceptable.These phases are shown in Figure 34.1, and discussed in more detail in the next sections.

34.3 Phase 0: Pre-Program Activities

Pre-program activities may be very simple or very difficult, depending on geographic and organizational

factors, such as the organizations mode of decision-making. The fundamental driver is geographic

is there a potential for earthquakes in regions in which the organization operates? While earthquakes

have the potential to occur almost anywhere, there are regions such as parts of California, Japan, and

Mexico, in which they are clearly a problem. There are other regions in which the degree of earthquake

risk is less clear in the eastern United States, for example, where earthquakes have occurred, but theirfrequency is relatively low. The region to be considered, by the way, is not only the region in which the

organization may be located, but also regions related to the organization, such as where the organizations

suppliers, or customers, are located.Chapters 1and4 of this volume should provide sufficient informa-

tion, in a global sense, to obtain a broad understanding as to whether earthquakes are a problem for a

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specific region. More detailed information can then be obtained from references cited in those chapters,

as well as from expert sources, such as the U.S. Geological Survey or various seismological observatories.

If earthquakes appear to have some potential for occurrence, the next issue is obtaining the authori-

zation for assessing the risk they may pose to the organization. Depending on the organization and itsdecision-making, several arguments may be needed to authorize the expenditure involved in a seismic

risk assessment. These arguments typically fall into the following categories:

Ethical this is often the first argument to occur to a proponent of a seismic risk assessment. It

typically takes the form of, it is the organizations responsibility to assess its earthquakes risk, to

be sure it is protecting life and property. This argument may sometimes be sufficient, but often

it is not, and it fails not because decision-makers are unethical, but rather because the argument

is insubstantial in itself. That is, logically, for this argument to prevail, it is then true that it is the

organizations responsibility to assess ALL risks, to be sure. Organizations cannot be risk-free,

and decision-makers are painfully aware of the limited resources they have available to deal with

quite real, significant risks, whether those risks are hurricanes, worker safety, foreign exchange,competition, or others. Therefore, the argument needs to be accompanied by sufficient facts and

initial analysis to substantiate that some ethical risk exists the proponent must do some

homework.

FIGURE 34.1 Earthquake mitigation program.

Pre-program

Assess the Risk

Develop the Program

N

Acceptable?Y

Stop

Acceptable?

Y

N

Implement the Program

Maintain the Program

Factors

- Seismic environment?

- Organization / decision-making

- Responsibility / liability

Data

- Seismic hazard

- Exposure

- life

- property

- business / function

- revenue

- data

- market share

- reputation / image

- Vulnerability

- Assessment

Mitigation Options

- Locational

- Redundancy / backup

- Move

- Structural

- Strengthen structures

- Brace equipment / furnishings

- Operational

- Emergency Plan

- Backup data

- Transfer

- Insurance

- Contracts



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Good business also known as enlightened self-interest, this is often the most effective argument.

A bit of homework, consisting of assembling some facts on (1) earthquake history of the region;

(2) how other organizations may have been affected in past earthquakes (see Chapter 1, this

volume) or even other disasters, such as hurricanes, floods, or fires; and (3) the approximate

exposure the organization has in the event of a structural collapse, loss of IT data, or other possible

event, can go a very long way toward convincing a CEO that it is worth looking into the matter

a bit further. Thus, the basis for a seismic risk assessment should be that it can be cost-effective,

reduce potential losses greatly should an earthquake occur, and possibly reduce current insurance

and other costs.

Liability In the United States and many other countries today, an ignorance-of-risk defense is

highly questionable, and this should be brought to the attention of decision-makers in a tactful

manner. Decision-makers are responsible for protecting the welfare of their organizations and the

public today, and are expected to understand the extent of this risk and to deal with it in a

responsible manner. Questions such as, Are you prepared? are valid, and not inappropriate

(Figure 34.2). After a disaster occurs, decision-makers are often held responsible for having made

the wrong decision, especially if losses are seen as unacceptably high and all stakeholders were notinvolved in the decision process. Steps to understand the risk and share the information with the

affected stakeholders can help to minimize post-event backlash, even if no action to mitigate is

ultimately taken. Once disclosure is made, the stakeholders can either accept the risk or make it

known that the risk must be addressed. In either event, the decision-maker who actively addresses

earthquake risk and involves all stakeholders is better off than one who does not.

Feasible Part of any argument for a seismic risk assessment should be that mitigation is feasible.

Decision-makers may believe they need to greatly mitigate or even totally eliminate risks once

they are discovered, relating this to issues of potential liability. Therefore, some decision-makers

may prefer to adopt an ignorance is bliss approach to risk management, avoid having positive

knowledge of a risk, and believe they have limited potential liability as a result. They believe thatif an earthquake causes a building to collapse, it will be considered an act of God for which they

will have no liability, particularly if no prior positive identification of the risk was available.

Opposing this is that it is often possible to obtain incremental reduction in risk by performing

limited mitigation as part of other programs. For example, if an existing building is going to be

expanded, seismic upgrade of the building can probably be accomplished concurrently, at little

additional cost. Similarly, if a major asbestos reduction program is going to be pursued, it may

be possible at very little additional expenditure to perform concurrent seismic upgrades. Until the

extent of seismic risk is understood and priorities set for mitigating this risk, the opportunities

to embark on such incremental and cost-effective programs cannot be identified.

Making the above arguments is not sufficient in themselves. A decision-maker will also want to knowwhat the next steps are, if he or she wishes to proceed. We discuss this aspect next.

34.4 Phase 1: Assessing the Problem

Assessing seismic risk, or risk screening, is discussed in some detail inChapter 2of this volume. Basically,

the process is shown inFigure 34.3, and consists of the following steps:

Identifying the assets (people, property, functions) at risk

Establishing (i.e., quantifying) the seismic hazard

Developing performance objectives

Performing first a risk screening and then, for selected structures, a more detailed review

Identifying the assets at risk should be relatively straightforward most organizations facilities

department should have values, personnel counts, etc. readily available. More difficult is determining

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the value of business or functional operations in a particular facility, and this may take a team effort

involving operations, the finance department, and perhaps others. Often, this aspect results in some

surprises, where a specific facility is found to be more critical than previously believed, due to its housing

high-value goods or operations. A classic example often encountered by the author is an organizations

data center, in which the equipment may be worth millions, and yet the building housing the data centerhas a book value only a fraction of the value of the equipment it houses. In this regard, the data itself

may be priceless (e.g., it would cost tens of millions to replace, and would result in hundreds of millions

in lost revenues if it could not be replaced), and therefore organizations have learned to back up the data

offsite, and its value is less an issue.

Developing performance objectives should normally be straightforward. A first priority is no loss of

life, which normally translates into no significant collapse hazard, and dangerous processes should be

able to safely shut down. Following in priority is normally preservation of value, which usually means

limited property loss, no loss of essential equipment, and restoration of operations onsite, or at a backup

site, within a period of time appropriate for the organization.

These two aspects, identifying assets at risk and performance objectives, can be qualitatively assessed

using a technique developed by Saaty [1980] termed the Analytic Hierarchy Process (AHP). At the coreof the AHP lies a method for converting subjective assessments of relative importance to a set of overall

scores or weights. It is a simple yet useful tool, and one of the more widely applied multi-criteria analysis

methods. The fundamental input to the AHP is the decision-makers answers to a series of questions of

FIGURE 34.2 The cover and following page from Guide for Decision-Makers, prepared by the California Seismic

Safety Commission, asks, Californias Next Earthquake are you prepared? and states, The public will want to

know whatyou did to prepare. (Courtesy California Seismic Safety Commission)



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the general form, How important is criterion A relative to criterion B? These are termed pairwise

comparisons. Questions of this type may be used to establish, within AHP, both weights for criteria and

performance scores for options on the different criteria. In AHP, a very simple series of weights, such as:

Much more = 5

About the same = 3

Much less = 1

are applied in a matrix, such that off-diagonal terms are the complement of one another (i.e., if row 1

column 2 is much more = 5, then row 2 column 1 is much less = 1). A simple example suffices.Suppose a company has the following facilities: headquarters, factory 1, factory 2, warehouse, and R&D

laboratory, and wishes to determine the relative value of these facilities on the basis of the number of

personnel, the value of building and contents, and the revenues that can be assigned to each facility. This

is a multi-criteria analysis (the criteria are lives, property, and revenues) problem. The first task is to

determine the relative importance of the criteria. This is done as shown in Table 34.1. In this table, life

is assigned a relative value much more than property, that is, a value of 5 (and, therefore, property is

much less, 1). The relative weights of the three criteria are thus:

Life = 10

Property = 4

Revenue = 4

The same technique is then applied to each of the facilities, for the facilitys respective values of life,

property, and revenue. For example, as shown inTable 34.2, headquarters contains 100 personnel, while

factory 1 contains 600, so that headquarters personnel are much less than factory 1 personnel, and

FIGURE 34.3 Earthquake risk assessment. (Courtesy California Seismic Safety Commission)

Occupants

Buildings

Other Structures

Equipment

Infrastructure

OperationsProfits

Market Share

Reputation

Identify Assets at Risk

Develop Performance Objective

Equipment

EstablishSeismic

Hazard

Buildings/Structures

ALTERNATIVES

Is it OK

per FEMA-

154?

No

Yes Yes

No

No No

Yes Yes

Is it OK

per MLEER

99-0008?

Is it OK

per Equipment

Assessment?

Is it OK

per FEMA-

310?

Risk Screening

Detailed Review

Stop Stop

Stop Stop



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much less than factory 2 personnel, much more than warehouse personnel, and about the same

as the R&D laboratory personnel (in numbers of personnel). The sum of the headquarters row is thus

10, which is multiplied by the weight assigned to life (which was 10), so that the life-weighted product

for headquarters is 100, for factory 1 is 180, and so on. This process is continued, and the final result is

shown inTable 34.3, where factory 2 is seen to be the most important facility (highest criteria-weighted

sum) and so on, to the least important facility (headquarters1).

Although it is somewhat arbitrary, the AHP is a useful tool for obtaining a relative ranking of facilities

during the risk assessment process.

Quantifying the hazard and developing seismic vulnerabilities are technical aspects that require theexpertise of specialist earth scientists, structural engineers, and related experts. Most organizations

utilize specialist consultants for this aspect who employ methods detailed in other chapters of this

volume. The methods can be highly quantified, although at a screening level of analysis such methods

may not be justified. It may simply suffice for facilities to be identified as being on good or poor

soils, from a seismic perspective, and the structures as being similarlygood or poor. In the latter

case, a structural engineers review in identifying a continuous lateral-force-resisting system (LFRS) is

a powerful discriminant.

The result of an earthquake risk assessment task is a statement of the potential damage and losses that

can result under currentconditions. An example is shown inFigure 34.4, which shows the findings for

a hypothetical arena that was judged to be a high collapse hazard. The result of the screening is typicallyqualitative.

34.5 Phase 2: Developing the Program

Having performed a risk screening, facilities may be usefully grouped into several categories, such as:

I. Probable high risk

II. Possible high risk

III. Probable low risk

with the benefit that the category III probable low risk facilities can be dropped from further consider-

ation. The category I and category II facilities should then be subjected to a more detailed analysis, the

product of which is not only a confirmation of their risk, but also the design of strengthening or

TABLE 34.1 AHP Results for Relative Weighting of Three Criteria

1 Authors note: a result that perhaps many employees already suspected.

1 LIFE

2 PROPERTY

3 REVENUE

4

5

6

7

Criteria

10

4

4

0

0

0

0

1

1

5

3

5

3

LIFE

PROPERTY

REVENUE

0 0 0 0 SUM



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development of other mitigation measures, including the estimation of costs for the mitigation measures.

Since this is not a final design, the estimate of costs for structural strengthening or other mitigation

measures is necessarily approximate, and is often termed a rough order of magnitude (ROM) estimate

of costs. An example of a Phase 2 more detailed analysis is shown inFigure 34.5, which shows results ofa structural analysis of a San Francisco Fire Department fire station performed under the authors

direction, including a schematic of the structural retrofit scheme and a ROM cost estimate. All facilities

falling into categories I and II should be the subject of similar analyses, for structural retrofitting or

alternative mitigation measures, as appropriate.

Based on analyses such as indicated in Figure 34.5, all category I and category II facilities can be ranked

according to their risk, mitigation costs, or other criteria. Table 34.4 shows an example of a hypothetical

seismic risk assessment performed for a municipality. Strengthening cost based on a Phase 2 structural

analysis is indicated for each facility. Additionally, the facilities are ranked by their benefit-cost ratio

(explained below), and the cumulative costs are indicated. The cumulative cost column indicates in what

order a limited budget is best spent. In this example, if the organization (i.e., the city) has only $20 million,

then it is best spent not on the Fine Art Museum, but on the North Police Station, Fire Station 2, and

the Aquarium.

This ranking is based on a benefit-cost ratio, developed on the basis of a set of rules created for

assessing the benefits resulting from assured seismic functionality of each facility. Benefit is the loss

TABLE 34.2 AHP Relative Weights for Facilities, for Two Criteria

1 HQ

2 Factory 1

3 Factory 2

4 Warehouse

5 R&D

6

7

Name of Facility Criteria

LIFE

100

600

900

25

50

HQ

R&D

Wareho

use

Facto

ry2

Facto

ry1

0 0 SUM10

18

18

6

8

0

0

100

180

180

60

80

0

0

Crtt1

5

5

1

3

1

3

1

1

1

3

1

1

5

5

5

3

3

5

5

3

1 HQ

2 Factory 1

3 Factory 2

4 Warehouse

5 R&D

6

7

PROPERTY

100

600

2000

200

400

HQ

R&D

Wareh

ouse

Facto

ry2

Facto

ry1

0 0 SUM6

14

20

8

12

0

0

24

56

80

32

48

0

0

Crtt2

5

5

3

5

1

5

1

3

1

1

1

1

3

5

5

3

1

3

5

3

0

0



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avoided by mitigation, derived by investing the cost of mitigation. If a large loss can be avoided via a

small investment, the benefit-cost ratio is high, and the investment is a good investment. If the required

investment is large and only a small loss is avoided, then the mitigation action is not cost-beneficial

that is, it is not worth it. These rules can be as simple as assessing the cost of loss of functionality of the

facility as the rent that would have to be paid to provide the same space, if that facility is lost. In the

case of a fire station, the benefit should be this rent, plus perhaps some allowance for the fire department

not being able to function in the earthquake disaster that is, some allowance for losses due to fireswhich the fire department cannot respond to (and also, perhaps, some allowance for lost lives, although

the latter are difficult to quantify). In the case of an art museum, some allowance might also be made

for damage to the high-value contents the works of art. While some works of art may be priceless

(even though they are bought and sold), a good proxy for the allowance would be the insurance premium

for the contents.

Thus, for each facility, the benefit is determined on a consistent basis, and that benefit divided by the

cost of mitigation. The facilities are then ranked by this ratio, as shown inTable 34.4. Such a ranking is

meant as a guide for decision-makers and should not be rigidly adhered to common sense may indicate

that a particular facility, although ranked low, may actually be more important than indicated. The true

meaning of this overriding of the ranking process is of course that the criteria employed in the process

did not truly reflect the actual, usually intuitive, criteria of the decision-maker.

The final decision as to what facilities to mitigate will depend on available budget or other resources

and is, ultimately, the final expression of the organizations acceptable risk. That is, the organization

must balance what it wishes against what it can afford. The final program, arrived at iteratively, expresses

what it can afford, and the allocation of resources is the indication of the risks the organization is willing

to incur. This is an important point, in that it is emphasized that the organizations acceptable risk cannot

be decided a priori it is arrived at in a give-and-take, once the potential losses, and the costs of reducing

those losses to various degrees, are known. Much time and effort are wasted in organizations at the

beginning of a risk reduction program, trying to decide what is their level of acceptable risk. Leave this

decision until the facts are known. Trying to determine acceptable risk early in the process can adversely

affect, even prematurely terminate, an earthquake risk reduction program.

TABLE 34.3 Criteria-Weighted Sums and Final Ranking for Each Facility

1 HQ2 Factory 13 Factory 24 Warehouse5 R&D6

7

Name of Facility

10080

18060800

0

PROPERTY

000REVENUE

0 SUM1402923401481600

0

Crtt1

Crtt2

1656805632

0

0

0

0

2456803248

0

0

LIFE

Crtt3

Crtt4

Crtt5

Crtt6

Crtt7

RANK52143



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FIGURE 34.4 Example result of a seismic risk assessment.



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FIGURE 34.5 Example Phase 2 seismic risk analysis, with rough order of magnitude (ROM) cost estimate. (Courtesy

EQE International)



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34.6 Phase 3: Implementing the Program

Implementing the program consists of several key steps, including:

Retaining seismic retrofit design professionals

Funding the program Performing final design

Coordinating design and construction with other parts of the organization

We discuss each of the aspects in turn.

34.6.1 Retaining Seismic Retrofit Design Professionals

Retaining engineers experienced in seismic retrofit is an important aspect of the retrofit process. One of

the most important attributes to look for is experience and satisfactory performance on previous projects.

As outlined above, the seismic retrofit professional will typically go about the assessment and mitigation

in a three-phased approach, consisting of: Initial investigation and screening

Detailed investigation and conceptual retrofit design and costing of alternatives

Final design and production of design documents and a bid package

Step two is perhaps the most crucial from the decision-making viewpoint, since this is where the alter-

natives are evaluated for cost and effectiveness.

In retaining an engineer, a clear and detailed scope of services should form the basis for the relationship.

The scope of services must of course be specific to the particular situation, but may consist of the following

tasks (services for all three phases are listed below).

34.6.1.1 Phase I: Initial Investigation and Screening

1. Review all available construction documents for the building, including structural and architectural

drawings and specifications for the original construction, as well as similar documents for any

significant modifications or upgrades. The purpose of this review shall be to determine the basic

TABLE 34.4 Example Result, Seismic Risk Assessment

Facility Strengthening Cost Cumulative Cost

North Police Station $82,600 $82,600

Fire Station 2 $115,500 $198,100Aquarium $6,047,300 $6,245,400

Natural History Museum $11,663,300 $17,908,700

Thompson Fine Art Museum $17,725,000 $35,633,700

Fire Station 17 $887,100 $36,520,800

Justice Center $6,960,300 $43,481,100

Municipal Building $10,497,400 $53,978,500

Central library $4,178,800 $58,157,300

South Police Station $1,154,500 $59,311,800

Fire Department Headquarters $2,149,900 $61,461,700

Fire Station 29 $2,590,400 $64,052,100

Municipal Building Annex $4,239,600 $68,291,700

Fire Station 24 $1,204,900 $69,496,600

Downtown parking garage $1,018,700 $70,515,300Jefferson Community Center $5,729,800 $76,245,100

Bayside library $1,428,400 $77,673,500

Lincoln Community Center $6,276,200 $83,949,700

Highest

Lowest

Benefit/Cost



13/21

structural load-carrying systems and to identify seismic performance issues related to configura-

tion and structural detailing.

2. Review available geotechnical reports for the site to determine a site class for use in developing

seismic hazards and to identify conditions that could lead to ground failure or other site instabil-

ities. Where site-specific soils data are not available, reference should be made to available gener-

alized geotechnical data, such as found on regional maps produced by the U.S. Geologic Survey

and the California Division of Mines and Geology. Reference should also be made to the seismic

safety element of local general plans.

3. Perform a seismic hazard for analysis for the site to identify the location of the site relative to

significant faults, and to estimate the probable intensity of ground acceleration as a function of

return period (or probability of exceedance).

4. Conduct a visual survey of the building to document the structures condition and to confirm

that available construction documents are representative of existing conditions. To the extent that

construction documents are unavailable, perform field investigation to develop sufficient infor-

mation to identify the vertical and lateral structural load-carrying systems, and to quantify their

strengths.5. Perform a preliminary structural evaluation to quantify the probable performance of the building

structure to resist the effects of ground shaking having a 10% probability of exceedance in 50

years. (Note that either more or less probable levels of ground shaking may be specified, based on

the importance of individual facilities. For facilities located within a few miles of major active

faults, it may be more appropriate to specify that the evaluation be performed for a median estimate

of the ground shaking resulting from a characteristic earthquake on that fault.) The evaluation

should, as a minimum, conform to the requirements of FEMA-310 [Federal Emergency Manage-

ment Agency, 1998] for a tier 1 evaluation. Alternative evaluations that quantify the adequacy of

the seismic-force-resisting system considering strength, ductility, and configuration issues may be

used.6. Develop an inventory of critical nonstructural components, including building utility equipment

(power supply, HVAC systems), operating equipment, ceilings, building fascia panels, elevators,

and fire protection systems. Identify the adequacy of installation of these nonstructural compo-

nents to resist damage.

7. Develop a preliminary opinion as to the probable performance of the facilities, in the event of the

designated earthquake ground motion (see item 5 above) using the performance levels contained

in FEMA-273 and FEMA-310 [Federal Emergency Management Agency, 1997, 1998].

8. Prepare a written report documenting the scope of study, the findings, and recommendations,

with written documentation of the evaluation process (FEMA-310 checklists, calculations, etc.)

included as appendices. If preliminary study indicates significant potential for earthquake-induced

ground failure and sufficient site-specific soils data are not available to conclusively assess this,the report should include a recommendation for site-specific geotechnical investigation. If the

existing construction of the structure is not sufficiently well defined to permit quantification of

its structural characteristics, include recommendations for detailed field investigations to confirm

the construction.

34.6.1.2 Phase II: Detailed Investigation and Conceptual Retrofit Design

1. Review the phase I evaluation report and available construction documents for the facility to develop

an overall understanding of the buildings construction and its probable seismic performance.

2. Conduct a visual survey of the building to observe the building condition and note obvious

deviations from the available documentation. Observe potential opportunities for introductionof seismic upgrade elements. Note sensitive areas of the building, such as historic spaces, traffic

corridors, etc. that may not be impacted by seismic upgrade measures.



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3. Meet with the facility manager to discuss alternative performance criteria and to select an appro-

priate criterion, or set of criteria. Also discuss restrictions on placement of retrofit elements, relative

to building appearance and functionality concerns.

4. If recommended in the phase I evaluation, perform field investigation of the building to confirm

the details of its construction and material strengths.

5. If recommended in the phase I evaluation, obtain site-specific geotechnical data to evaluate

potential ground failure and associated mitigation measures.

6. Perform structural engineering calculations to quantify seismic deficiencies in the building relative

to the selected performance levels. As a minimum, the criteria of FEMA-310 for a tier 2 evaluation

should be performed. Alternatively, the performance analysis procedures contained in the Cali-

fornia Building Code, Division IIIR, in FEMA-273, or in the California Seismic Safety Commis-

sions SSC-9601 may be used.

7. Review alternative potential methods for seismic upgrade for each specified performance criterion,

to a level sufficient to confirm feasibility and to select a recommended approach. Meet with the

facility manager to review the alternatives and to agree on the appropriateness of the recommended

approach.8. Develop conceptual-level upgrade designs for each specified performance criteria. Supporting

calculations shall be performed to a sufficient level of detail to confirm that the overall size and

scope of the recommendations are appropriate. The level of detail should be sufficient to permit

an ROM cost estimate to be performed. Consideration should be given to collateral upgrades

triggered by the seismic work, including disabled access, fire/life safety, and other code upgrades.

9. Prepare conceptual-level sketches showing recommended upgrades for nonstructural components.

10. Prepare preliminary cost estimates for the recommended seismic upgrade work, for each perfor-

mance criterion, together with required collateral upgrades.

11. Prepare a report indicating the scope of the study, the findings with regard to building deficiency

and performance, and the recommendations for alternative levels of upgrade, as well as anyrecommendations for additional investigation to be performed as part of final design. Include

schematic drawings documenting the upgrade recommendations and cost estimating worksheets

in an appendix.

34.6.1.3 Phase III: Construction Documents and Construction Support

1. Assemble a complete design team, including project management, structural engineering, archi-

tecture, mechanical and electrical engineering, and cost estimating, as required to support the

development of construction documents.

2. Review all available documentation for the building as well as previous evaluation reports and

supporting calculations in order to develop an understanding of the building deficiencies and

recommended upgrade approach.3. Meet with the building official as necessary to confirm the design criteria and proposed approach,

as well as to confirm the extent of required collateral upgrades.

4. Develop construction documents, including drawings and specifications, together with supporting

calculations, to implement the recommended structural upgrades, together with all required

collateral upgrades. Submit copies of construction documents to client for review, at the 40% and

90% stages of completion. Final construction documents shall be suitable for obtaining building

permits, competitive construction bids, and for executing the work.

5. Prepare an estimate of probable construction cost at each stage of document submittal and for

the final construction documents.

6. Provide support to client in the development of bid packages for construction contracts.7. Respond to comments from plan checkers and revise construction documents as necessary to

obtain approval.

8. Respond to bidder requests for clarification.



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9. Provide support to client in evaluation of construction contract bids for completeness and con-

sistency with the requirements of the construction documents.

10. Attend periodic meetings at the construction site, during the construction period, to coordinate

construction progress.

11. Conduct periodic site visits to confirm that the work is generally being conducted in accordance

with the design requirements.

12. Review contractor submittals and shop drawings.

13. Respond to contractor Requests for Information and assist client in negotiation of contractor

change order requests.

14. Review special inspection and test reports.

15. Perform a walkthrough of the project site at 95% completion to develop a punchlist of items not

completed by contractor.

34.6.2 Funding the Program

Like all programs, earthquake risk management requires the investment of funds. The initial phases ofthe program, in which the risk is assessed and mitigation options explored, typically entails relatively

modest cost. By spreading these tasks out over a period of one or two years, most organizations will be

able to accommodate these costs within their normal operating budgets. However, major programs of

capital improvement will typically require extraordinary sources of funding. The following sources should

generally be considered when planning programs of seismic mitigation:

General operating and maintenance funds. Not all seismic upgrade projects are particularly costly

and some seismic upgrades can be done at nominal cost. For example, most equipment items can

be anchored or braced for seismic resistance at a per-item cost of a few hundred dollars or less.

Many organizations will be able to cover significant seismic upgrade activities out of their general

operating and maintenance funds. Bond issues. If an organization understands its existing earthquake risk and is convinced that this

is unacceptable, it may be willing to support additional bonded indebtedness as a means of raising

the necessary funds. This is a particularly appropriate mechanism for the public sector. For

example, the City of San Francisco obtained permission from its electorate to raise more than

$100 million for earthquake safety retrofits offire stations and other municipal buildings. From

a strategic perspective, such bond measures are most successful in the period immediately follow-

ing a major earthquake somewhere in the world, when the publics attention is drawn to the issue

of earthquake risk.

Special use fees. In some cases, it may be possible to support the cost of seismic upgrade through

the establishment of special use fees. As an example, the State of California raised tolls on bridgescrossing San Francisco Bay as a means of funding seismic upgrades of these structures.

Hazard mitigation grants. Occasionally, special grants become available from the federal and/or

state government for partial funding of seismic mitigation work. These grants may be offered as

(1) seed money for demonstration projects, to encourage and attract other sources of funding; or

(2) in order to reduce risk of damage in future earthquakes and to help communities become

more self-sufficient. These grants are usually available only for public or nonprofit organizations

and often are restricted to, or give preference to, certain types of projects. For example, using

funding obtained under the Proposition 122 bond program, the State of California made limited

mitigation funding available to cities, counties, and similar agencies. Generally, projects to

strengthen emergency response facilities, such as fire stations, police stations, and city halls,

received priority over other types of projects. When mitigation grant programs are available,

communities must typically apply for funding in competition with others. In addition, it is usually

necessary for the enterprise to provide some co-funding of the project, often in the amount of 10

to 20% of total project costs.



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Tax preferences and credits. Certain tax credit and tax preference incentives are available for the

rehabilitation of facilities. Special facilities, such as qualified historic landmarks, are prime candi-

dates for other tax incentives. These incentives are typically applicable only to private, for-profit

enterprises. In order to qualify for these incentives, it is necessary to comply with certain historic

preservation standards and to be subjected to a review and approval process for the design.

34.6.3 Coordinating with Other Parts of the Organization

It is very important to include earthquake risk mitigation measures with other facets of an organizations

asset management program. Key issues related to this are the following:

Often, by performing seismic upgrade work concurrently with other planned projects, it is possible

to reduce the cost and disruption of the upgrade work. For example, a common requirement of

seismic upgrade programs for low-rise buildings with wood roof structures is to increase the

nailing of the plywood roof sheathing. This can only be done upon removal of the roofing. Clearly,

if such upgrade work is performed concurrently with routine replacement of the roofing system,

it will be far more economical.

If an existing facility is assessed as incapable of providing adequate seismic performance for its

current use, consider changing its mission to be more compatible with its seismic performance

category. For example, if a critical care wing of a hospital is judged incapable of immediate post-

earthquake occupancy, and there is simultaneous need to develop new outpatient care at the

facility, the best choice may be to build new critical care space and convert the existing space to

use for outpatient care.

Consideration should be given to the length of time a facility is expected to remain in service. If

a facility is scheduled for replacement or retirement in the near future, it makes little sense to

invest in upgrade of the facility.

Construction for seismic improvements to a facility will often trigger mandatory requirements toperform other types of upgrades, such as disabled access improvements, hazardous material

abatement, and fire/life safety improvements. These collateral upgrade requirements can have

substantial impact on the implementation cost and, in some cases, the cost of collateral upgrades

is higher than the seismic construction cost. It is important to account for these impacts when

evaluating the cost of seismic mitigation.

Earthquake risk cannot be managed effectively in a vacuum. The decision-maker and the risk manager

must involve the facilities or asset manager in planning and implementing the mitigation program in

order to assure that collateral issues are addressed and all capital improvements are coordinated. It is

also important to ask professional consultants, who may be retained to assist in quantifying risk and

suggesting mitigation alternatives, to be mindful of these needs.

34.6.4 Perform Seismic Retrofit

Performing the seismic retrofit consists of the following steps:

1. Retaining a team of design professionals to develop construction documents, using the phased

approach described above. Result: a series of specifications for performing the desired upgrade

work and reliable estimates of probable construction cost.

2. Identifying funding sources for performing the work. Available funding sources were discussed in

the previous section, and include:

General operating and reserve funds

Grant programs operated by HUD (Housing and Urban Development), FEMA, and other

agencies

General obligation bonds



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Result: sufficient funds to execute the required construction work.

3. Hiring retrofit contractors. This is an important aspect of the retrofit process. As with hiring a

contractor for any other purpose, one of the most important attributes to look for is experience

and satisfactory previous performance. Generally, public agencies will have to use a competitive

bid process for the selection of a contractor. It is recommended that a process of bidder prequal-

ification be performed, prior to requesting construction bids, to assure that bidders have adequate

resources and experience. Result: on-board contractor, ready to go.

4. Scheduling the work so as to minimize disruption, in coordination with tenants, managers, or

operators, is another important aspect. Note that construction scheduling can have a significant

impact on construction costs. Therefore, any scheduling requirements or constraints that will be

imposed on the contractor, such as limiting work to certain periods of time or requiring that work

in certain sections of a facility be staged, should be clearly included in the general conditions

section of the specifications used to solicit contractor bids. The selected contractor should be

requested to submit a detailed construction schedule, incorporating the client-specified milestones

and indicating the specific timing of work by different trades. Result: schedule for construction.

5. Construction. Result: retrofitted facilities.6. Maintaining the retrofitted facility. Retain as-builts, specifications, and engineers maintenance

instructions in the retrofitted building or other archive. Use a plaque or other notice to ensure

that these materials are not lost or overlooked. Result: complete record of retrofit.

34.6.5 Dealing with Residual Risk

After the seismic upgrade work has been completed, the seismic risk associated with a facility will be

greatly reduced from original levels. However, some residual risk will remain. Prudent risk management

suggests that effective steps be taken to further minimize the residual risk, through the steps outlined

below.

34.6.5.1 Emergency Plan

Even relatively minor damage to a facility can result in extended interruption of service and loss of use,

if no-one knows what to do about assessing its condition, securing potentially hazardous contents and

utilities, and conducting repairs so that service can be restored. Emergency response plans that clearly

designate the persons responsible for each of these actions, and how they can be contacted in the event

of an emergency, can significantly reduce the amount of confusion and lost time when an earthquake

actually occurs.

In addition to basic information on who is responsible for specific actions when an emergency occurs,

emergency response plans should include information on the critical equipment and systems within the

building, the structural system, expected types and locations of damage, and checklists for specific post-

earthquake actions to be taken. For critical facilities, the emergency operations plan can also include

provision for alternative work spaces, in the event that damage is so severe that reoccupancy of the facility

within the short term is not feasible.

34.6.5.2 Risk Transfer

Earthquake insurance can be an effective method of guarding against the direct financial losses associated

with an earthquake and is commonly used in the private sector for this purpose. Earthquake insurance

is very effective in reimbursing a property owner for the direct costs related to repair of damage. It is

less effective with regard to reimbursement for business interruption costs, as often the quantification

of these costs is difficult and therefore subject to dispute. It is also important to note that most earthquake

insurance policies include significant deductibles and will not cover upgrades to the facility that may betriggered by the building official as part of damage repair work. The cost of earthquake insurance is

highly variable and depends as much on the global financial markets and health of the insurance industry

as it does on the actual risk associated with a facility. In some years insurance can be obtained at a fraction



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of its real value, while in other years, it may cost several times its actual value or may not be available at

all. This is why it is prudent not to rely on earthquake insurance as the sole means of risk management.

Another aspect of risk transfer involves an organizations suppliers and customers. To the extent that

provisions for special circumstances in the event of an earthquake can be written into contracts, then

the earthquake risk has been transferred. For example, if obligations to purchase supplies or deliver

product can be relaxed in the event of an earthquake, then additional time is gained by the organization

during its crisis period. Keeping this aspect in mind during contract negotiations, as an ongoing aspect,

can pay handsome dividends in the event of an earthquake, at little or no cost.

34.6.5.3 Physical Redundancy and Geographic Dispersion

One of the most effective techniques for mitigation of earthquake risk is to disperse operations into

independent locations at different sites. Although the effects of earthquakes can be widely dispersed over

a region of many square miles, the most extreme earthquake effects are typically limited to a small fraction

of the affected region. If all of the physical facilities associated with an operation are concentrated at a

single site or location, there may be significant potential for damage to this physical facility to completely

interrupt operations for an extended period of time. However, if the physical facilities are dispersed tomultiple locations, it becomes much less likely that all of these facilities would be damaged to an extent

that would limit operations at all of the locations. Thus, dispersion can become an effective tool to

maintain at least partial operational capability following a major earthquake. To the extent that the

dispersed facilities provide redundant capacity, it may be possible to provide full operational capability

if some of the facilities become damaged.

34.6.5.4 Data Backup

Redundant storage of critical records and data can be a highly effective risk mitigation technique.

Following the 1989 Loma Prieta earthquake, the City of Oaklands Building Department found itself

displaced from City Hall, which had been severely damaged by the earthquake. The building department

stored microfilm copies of the original construction drawings for private buildings in archives maintainedwithin City Hall. The red-tagging of that building effectively made these records unavailable for many

months following the earthquake, hampering the efforts of the community to assess and repair damage

sustained by other buildings. Had a redundant set of microfilm records been maintained in another, off-

site, location, it is highly unlikely that access to both sets of data would have been lost.

Public agencies and private businesses can maintain their own off-site records storage or, alternatively,

they can rely on any of a number of providers of this service. This may be particularly important for

electronic records that are maintained on-line. There are a number of private data centers that provide

stand-by electronic records storage, as well as data processing capability.

34.6.5.5 Retain Structural Engineers and Contractors

Following the 1989 Loma Prieta earthquake, the City of San Franciscos Building Inspection Department

found itself overwhelmed by the demand to perform post-earthquake safety inspections of public and

private buildings in the city. Even with the assistance of many volunteer inspectors, it took a period of

months before all buildings were evaluated and their conditions determined. During this period of time,

building owners and tenants were often at a loss to know whether it was safe to reoccupy damaged

buildings, leading to extensive economic losses.

In order to avoid these problems in future earthquakes, the City of San Francisco later established the

voluntary Business Occupancy Resumption Earthquake Inspection Program (BOREIP). Under the

BOREIP, building owners can retain qualified structural engineers to perform post-earthquake inspec-

tions of their buildings in the event of a future earthquake. These engineers must develop a

post-earthquake inspection plan for the building and be certified by the city as deputy building inspectorsfor the specific building. Under the program BOREIP inspectors are obligated to perform post-earthquake

inspections within 36 hours of the occurrence of an earthquake disaster. They then have the authority

to post buildings, as inspected, following an earthquake, on behalf of the city.



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Building departments can develop similar programs to speed the post-earthquake recovery of their

communities. In addition, even in the absence of such programs, individual public and private building

owners and tenants can retain structural engineers to perform rapid post-earthquake assessments of

buildings, to advise as to whether the buildings are safe for occupancy and to develop repairs in the event

these are required. While these engineers would not have the power to officiallypost a building, they

can provide assurance as to the condition of its structure and appropriate recovery actions. It is often

beneficial to develop retainer agreements with engineers before the earthquake actually occurs. In the

days and weeks immediately following a major earthquake, structural engineers are extremely busy and

are unlikely to be available on short notice unless advance arrangements have been made.

It may also be beneficial to develop similar retainer agreements with general contractors, so that there

is assurance that in the event repairs are needed, construction capability to effect these repairs will be

available.

34.7 Maintaining the Program

In many ways, the actual earthquake mitigation program has been performed when the following actionshave been carried through to completion:

Facilities have been strengthened, or otherwise dealt with such that their risk is acceptable.

Emergency response and business continuity plans have been developed and exercised.

Residual risk has been insured, transferred, or accepted.

However, organizations are dynamic and facilities, operations, and personnel are constantly changing.

Thus, documentation of the steps taken, including the process and criteria, is an important step to

complete. As new facilities or operations are developed, the same or enhanced criteria can be applied to

them, thus retaining the overall balance of the earthquake mitigation program. As new personnel join

the organization, they can review the earthquake mitigation program documentation and maintain theoverall goals.

Finally, when (not if) the earthquake occurs, there are a number of important steps to be quickly

performed, including:

1. Assessing the extent of damage. The first thing that should be done following an earthquake is to

assess the extent of damage that has occurred. It is necessary to assess whether physical facilities

that are relied upon for operations are functional and safe, as well as to estimate the amount of

time they may be out of service. It is impossible to implement an effective response and recovery

program until these data are known. For many public agencies, the responsibility for post-earth-

quake damage assessment may extend beyond the need to assess the performance of the physical

facilities that the agency relies upon for operation, to include an assessment of the extent of damageand loss that has occurred community-wide. For example, if housing in a community is severely

impacted, public agencies will be expected to provide for the temporary shelter and care of

displaced families. If a number of building collapses have occurred, public agencies will be expected

to assist in locating and extracting victims. In order to effectively respond to such needs, it is

necessary to be able to rapidly assess the likely extent of damage and loss. These assessments can

be made by performing rapid post-earthquake reconnaissance or, alternatively, by implementing

one of several disaster simulation software packages that permit rapid estimation of losses. Regard-

less of the method an agency or business elects to pursue, a current emergency response plan and

previously negotiated agreements with necessary engineering consultants and contractors can

speed this phase of the recovery effort.2. Implementing emergency operations procedures. As soon as an assessment of damage is made, and

the extent of impairment of ability to provide service and the need for these services is ascertained,

recovery operations should commence. In the period immediately following the earthquake,

individual public agencies and private businesses will have to rely on their own resources. An



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effective emergency response plan can help to smooth the difficult immediate post-event recovery

period. Within days to weeks, outside assistance will begin to become available from such sources

as FEMA, the State of California Office of Emergency Services, the American Red Cross, and other

volunteer agencies. In extreme emergencies, military assistance may also be made available.

3. Restoring normal operations. Over a period of days to weeks and, in the worst disasters, perhaps a

period of years, normal operations will be restored. The length of time necessary for restoration

of normal operations will be directly dependent on the severity of the event, as well as the extent

to which risks were identified and mitigated, and emergency response plans developed prior to

the event. It many cases, what is deemed to be normal operations after the earthquake is not

the same condition that existed before the event. Earthquakes can have far-reaching economic and

social impacts that can completely change the character of a community and the long-term

profitability of individual businesses. For this reason, it is particularly important that public leaders

view earthquake risk reduction not only as their responsibility with regard to protection of public

facilities, but a responsibility that the entire community must share. One of the major benefits of

proactive risk mitigation on the part of a public agency is that it sets a leadership example for the

community at large.4. Assessing the lessons learned. An important but often overlooked concluding step in the process is

a carefully conducted review of the loss and recovery experience. No matter how well prepared a

community or business is for an emergency, it will typically find that unanticipated problems

developed and that preparation could have been better. Although severe earthquakes are rare

events, it is possible for some communities in California, Japan, or other high seismicity regions

to experience major damaging events several times during a typical lifetime. The San Fernando

Valley, for example, experienced large-magnitude events in both 1971 and 1994, located within a

few miles of each other. A careful assessment of what went wrong and what went right in the

disaster can allow for better preparation for the next event, as well as serve as valuable learning

tools for other communities that have not yet been affected by earthquake disaster.

Defining Terms

Benefit The loss avoided by mitigation.

Benefit-cost ratio Ratio of avoided losses to cost required to avoid those losses. Both amounts shouldbe computed on the same basis. For example, if the mitigation cost is the current cost of

retrofitting, then the benefit should be computed in present value dollars.

Earthquake mitigation Actions taken to reduce the effects or unwanted consequences of earthquakes,such as human casualties, structural damage, or business interruption. Actions can be taken

prior to an earthquake (e.g., strengthening a building) or after the earthquake (e.g., activating

a business continuity plan).Exposure What is at risk that is the total value of assets that could conceivably be lost due to a

hazard such as earthquake. If 100 workers are employed in a company in or near one location,

that companys exposure at that location is 100 employees.

Lateral-force-resisting system (LFRS) The structural system in a building or structure that resistslateral forces, arising, for example, from an earthquake. In order to resist an earthquake, a

structure must have a LFRS continuous to the foundation. Surprisingly, many pre-code struc-

tures may not have a demonstrable LFRS, and therefore are collapse hazards.

Risk management An integral activity of an organization, normally centralized in a risk managementdepartment headed by the risk manager and associated with the chieffinancial function. Ideally,

risk managers monitor and manage all sources of risk to the organization aside from those

associated with the organizations central mission. For example, in a manufacturing company,

the risk manager will deal with property, life, and health risk, but not market or foreign exchange

risks or worker safety. In dealing with property risk, the risk manager will normally purchase



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property insurance, but will also examine alternatives to insurance, such as strengthening a

building for earthquake so as to reduce the need for earthquake insurance.

Rough order of magnitude (ROM) estimate of costs ROM estimates are made at an early stage inthe design or development of a project. By ROM is not meant, in the mathematical sense,

variations on the order of powers of 10, but rather within a factor of

2. Therefore, if the ROMcost estimate for strengthening a building is $1 million, it is anticipated that the final cost will

not be less than $500,000 and not more than $2 million. ROM estimates are refined in later

stages of the design or development process, such that final cost estimates are usually20%

or less.

References

Federal Emergency Management Agency. 1997. NEHRP Guidelines for the Seismic Rehabilitation of

Buildings, FEMA 273, prepared by the Building Seismic Safety Council for the Federal Emergency

Management Agency, Washington, D.C.

Federal Emergency Management Agency. 1998. Handbook for the Seismic Evaluation of Buildings: APrestandard, FEMA 310, prepared by the American Society of Civil Engineers for the Federal

Emergency Management Agency, Washington, D.C.

Saaty, T. 1980. The Analytical Hierarchy Process, John Wiley & Sons, New York.

Further Reading

Earthquake Risk Management: A Toolkit for Decision-Makers, prepared by the California Seismic Safety

Commission and available via their Web site (www.seismic.ca.gov), is a useful compendium of methods

and tools for developing and implementing an earthquake mitigation program. The author was involved

in the development of the Toolkit and drew on it for this chapter, but it contains much additional material

and is highly recommended. Also recommended are two accompanying publications:A Guide for Deci-sion-Makers and Earthquake Risk Management: Mitigation Success Stories, both also available via the

Commissions Web site.
http://www.seismic.ca.gov/http://www.seismic.ca.gov/http://www.seismic.ca.gov/

Developing an Earthquake Mitigation Program

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