Proceedings of the International Symposium on Engineering Lessons Learned fromthe 2011 Great East Japan Earthquake, March 1-4, 2012, Tokyo, Japan

EMERGENCY EVACUATION OF
FUKUSHIMA RESIDENTS LIVING IN THE VICINITY
OF NUCLEAR POWER STATION
Tomoaki NISHINO1, Masaki OUCHI2, Shin-ich TSUBURAYA3, Takeyoshi TANAKA4, andAkihiko HOKUGO5
1Assistant Professor, Graduate School of Engineering, Kobe University,
Kobe, Japan, tomoaki.1098@dolphin.kobe-u.ac.jp
2
Graduate Student, Graduate School of International Cooperation Studies, Kobe University
Kobe, Japan, youandi2635@gmail.com
3
Chief Engineer, Mitsubishi Heavy Industries,
Kobe, Japan, shinichi_tsuburaya@mhi.co.jp
4Professor, Disaster Prevention Research Institute, Kyoto University,
Kyoto, Japan, takey@imdr.dpri.kyoto-u.ac.jp
5Professor, Research Center for Urban Safety and Security, Kobe University,
Kobe, Japan, hokugo@kobe-u.ac.jp

ABSTRACT: The purpose of this study is to prepare the basic data available on themodeling of full-scale emergency evacuation behavior in nuclear disaster, by clarifying apart of the actual situation in the Fukushima Emergency Event from the following
surveys: (1) interview surveys on response of local government offices to full-scaleevacuation; and (2) questionnaire surveys on evacuation behavior of residents. In thispaper, we described the content of the surveys and analyzed the obtained data in terms of
behavior type and required time.
Key Words: full-scale evacuation, disaster response, resident evacuation, Fukushima
Hamadori area

INTRODUCTION
Once radioactive materials are released at an abnormal level in the air from a nuclear facility suchas nuclear power station, it is essential to make a tremendous number of residents in a broad areaaround the facility evacuate immediately to the area where radiation exposure hardly cause a problem.
In the Fukushima Emergency Event (2011), all of the residents within 20 kilometers from a station
were ordered to evacuate out of the target area by the prime minister, so that most of the municipalities
in the vicinity of the station were forced to carry out a full-scale evacuation to other municipality, inspite of suffering from the Great East Japan Earthquake until just before.
In such an event, a tremendous number of residents have to rely on automobiles suitable forlong-distance travel, so that there is fear that the extension of evacuation time due to traffic jams on
evacuation roads may increase the amount of radiation exposure. In order to resolve such a problem, it

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is important to make an effective evacuation plan in advance, considering the evacuation time. For
such a planning, it is essential to develop a reasonable method which can predict the full-scale
emergency evacuation behavior of individual residents in nuclear disaster in time series.
Several attempts have been made in clarifying emergency evacuation behavior in nuclear disaster.
As to the JCO accident of Japan (1999), which is the first case that the protection measure was taken
in Japan, the contact situation of disaster information and the reaction of residents at that time havebeen analyzed (Umemoto et al. 2002). However, the accident did not lead to the event that theresidents all over the municipality were required to evacuate immediately; i.e. the target area of
evacuation order was within a few hundred meters radius from the facility. After that, transportation
choice by a resident for long-distance evacuation, such as a few dozen to one hundred kilometers, hasbeen modeled based on the results of the attitude survey (Umemoto 2011). However, it is not still
known how long each behavior is required under the issued situation of full-scale evacuation order,
such as time required from the issue to the start of evacuation.
So the purpose of this study is to prepare the basic data available on the modeling of full-scale
emergency evacuation behavior in nuclear disaster, by clarifying a part of the actual situation in the
Fukushima Emergency Event from the following surveys: (1) interview surveys on response of local
government offices to full-scale evacuation; and (2) questionnaire surveys on evacuation behavior ofresidents. In this paper, we described the content of the surveys and analyzed the obtained data interms of behavior type and required time.

RESPONSE OF LOCAL GOVERNMENT OFFICESTO FULL-SCALE EVACUATION
Fig. 1 shows the destination for refuge of the local government offices which carried out
full-scale evacuation, where the data were collected from newspaper reports. In the Fukushima
Emergency Event, evacuation orders based on radius from the stations were issued five times from thenight of the earthquake (March 11th) to the night after the day (March 12th) by the Prime Minister,
according to the escalation of accident situation such as a hydrogen explosion (Nuclear Industrial

Fukushima

N

Pacific Ocean

Kawamata
Nihonmatsu

Katsurao
Namie

Koriyama

FutabaFukushima Daiich

TamuraOkuma
KawauchiTomioka
Fukushima Daini

Ono

NarahaHironoNuclear Power Station
Local government office
0

10

20

30km

Iwaki

Fig. 1 Destination for refuge of local government offices.

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Safety Agency 2011). Even after that, the escalation continued, so that eight municipalities carried out
full-scale evacuation by March 16th. The main events of station situations and protection measures by
the Prime Minister are outlined as follows: (1) at 7:03 PM on March 11th, the Prime Minister declared
an emergency situation; (2) at 9:23 PM on March 11th, the Prime Minister ordered all of the residents
within 3 kilometers from Fukushima Daiichi Nuclear Power Station “1F” to evacuate out of the target
area; (3) at 5:44 AM on March 12th, the Prime Minister ordered all of the residents within 10
kilometers from 1F to evacuate out of the target area; (4) at 7:45 AM on March 12th, the Prime
Minister ordered all of the residents within 3 kilometers from Fukushima Daini Nuclear Power Station“2F” to evacuate out of the target area; (5) at 3:36 PM on March 12th, hydrogen explosion took place
at 1F; (6) at 5:36 PM on March 12th, the Prime Minister ordered all of the residents within 10
kilometers from 2F to evacuate out of the target area; (7) at 6:25 PM on March 12th, the Prime
Minister ordered all of the residents within 20 kilometers from 1F to evacuate out of the target area;(8) at 11:01 AM on March 14th, hydrogen explosion took place again at 1F; and (9) at 11:00 AM on
March 15th, the Prime Minister ordered all of the residents within 20-to-30 kilometers from 1F to stayindoors.
Outline of Interview Results
Generally, the municipalities included within 8-to-10 kilometers from a nuclear power station has
been obligated to develop a disaster prevention plan for nuclear disaster (Nuclear Safety Commissionsof Japan 2010); i.e. some municipalities owned no plans in the Fukushima Emergency Event. When an
office makes residents evacuate to other municipality, the following operations are usually consideredin the plan: (1) an office decides to carry out full-scale evacuation depending on the order by the Prime
Minister or based on the independent judgment; (2) an office requests the accommodation of residents
to other municipality; (3) an office ensures vehicles to transport residents by itself or by receiving
support from the Japanese government and prefecture; (4) an office issues evacuation order andinforms residents; and (5) an office makes residents gather at several points and transport them toother municipality.
Table 1 shows the content of disaster operations carried out by the local government offices of
Okuma town, Tomioka town, Naraha town, Katsurao village, and Kawauchi village, where the data
were obtained from interview surveys to the officers. Of these, as to the issue time of full-scaleevacuation and the completion time of transportation, the positional relationship with the stations andthe target area of evacuation order by the Prime Minister is illustrated in Fig. 2. The origin of an arrow
indicates (1) the time when an office issued full-scale evacuation order, and (2) the straight distance of
an office from a station. The end of an arrow indicates (1) the time when an office finishedtransporting residents to other municipality, and (2) the straight distance of destination for refuge of an
office. The parenthetic number indicates the number of residents who were housed in shelters
established in the municipality of destination for refuge. Okuma town and Tomioka town decided
full-scale evacuation because the offices themselves were included in the range of evacuation order byTable 1 Disaster operations carried out by local government offices.
Municipality

Okuma

TomiokaNarahaKatsurao

KawauchiPopulation

11,51516,001

7,700

1,531

Households

3,955

6,141

2,576

470

950

2011, 5/21

2011, 6/4

2012, 1/24

2011, 4/30

2011, 4/30

Date of the interview
Ownership of disaster prevention plan

2,820

Own

Own

Own

Not own

Not own

3/12 6:00

3/12 7:00

3/12 8:00

3/14 21:00

3/16 9:30

Municipality of destination for refuge

TamuraKawauchi

Iwaki

Fukushima

Koriyama

Number of vehicles for transportation

50

8

6

5

8

Vehicle support from Japanese government and prefecture

Supported

Unsupported

Unsupported

Unsupported

Unsupported

Completion time of transportation

3/12 15:00

3/12 17:30

3/12 16:00

3/14 23:00

3.16 23:00

4,000

6,200

5,300

470

600

Issue time of full-scale evacuation order

Number of residents housed in shelters of destination

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the Prime Minister. On the other hand, the other municipalities decided full-scale evacuation based on
the independent judgment before the offices being including. As a result, any of the offices chose theaccommodations more than 20 kilometers away from the stations as the destinations for refuge. It took
more than half a day for all of the offices except Katsurao to finish the transportation of residents fromwhen the office issued full-scale evacuation order.
As a result, we could obtain the response types of local government offices as shown in Fig. 3, byassuming the following elements as the determination elements: (A) whether or not an office owns thedisaster prevention plan; (B) whether or not an office decides full-scale evacuation based on the
independent judgment before the office being included in the target area of evacuation order by thePrime Minister; and (C) whether or not an office receives support of vehicles from the Japanese
government and prefecture.

BEHAVIOR SURVEY ON FULL-SCALE EVACUATIONOF RESIDENTS AFTER EARTHQUAKEBefore conducting the questionnaire surveys, it is essential to define the evacuation targeted inthis study. By the time residents start long-distance evacuation from nuclear disaster, they usually takeDistance from 1F (km)
15:00
3/11
(Fri.)

0

10

20

40

Distance from 2F (km)
50

60

70

15:00

Earthquake

18:00

3/11
(Fri.)

Evacuation order R=3km from 1F
0:00

0Evacuation order R=10km from 1F

3/12(Sat.)

Tamura Athletic Park
(6,200)

18:00

24:00

40

50

60

70

Evacuation order R=3km from 2F(5,300)

12:00

Iwaki Chuodaiminami
Elementary School

Evacuation order R=10km from 2F

18:00

Hydrogen explosion at 1F
Evacuation order R=20km from 1F

30

NarahaKawauchi

18:00

20

6:00

Tomioka(4,000)

12:00

10Earthquake

0:00

Okuma

6:00
3/12
(Sat.)

30

24:00
Issue time of full-scale evacuation order by local government office

Issue time of full-scale evacuation order by local government office(XXX) Number of evacuees to destination for refuge of local government office(XXX) Number of evacuees to destination for refuge of local government office

Destination for refuge of local government office and complete time of evacuation

Destination for refuge of local government office and complete time of evacuation

Target area for evacuation order by the Prime Minister

Target area for evacuation order by the Prime Minister

Distance from 1F (km)
6:00

0

10

20

30

40

50

60

Evacuation order R=20km from 1F
Indoor stay order R=20-30km from 1F

12:00
3/15
(Tue.)
18:00

Distance from 1F (km)
0:00

0

10

12:00

18:00

30

40

50

60

70

0:00

Evacuation order R=20km from 1F

6:00
3/14
(Mon.)

20

6:00

Hydrogen explosion
at 1F

3/16
(Wed.)

Katsurao

Nihonmatsu Azuma
Athletic Park

Kawauchi

12:00

18:00

Hydrogen explosion
at 1F

(600)
Koriyama Big Pallet

(470)

24:00

24:00
Issue time of full-scale evacuation order by local government office

Issue time of full-scale evacuation order by local government office(XXX) Number of evacuees to destination for refuge of local government office(XXX) Number of evacuees to destination for refuge of local government office

Destination for refuge of local government office and complete time of evacuation

Destination for refuge of local government office and complete time of evacuation

Target area for evacuation order by the Prime Minister

Target area for evacuation order by the Prime MinisterFig. 2 Issue time of full-scale evacuation and completion time of transportation.

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70

Decision-making

Vehicles forTransportation

Owned

Independent

Supported

R1

Unsupported

R2

NarahaSupported

R3

Okuma

Unsupported

R4

Tomioka

Supported

R5

Unsupported

R6

Supported

R7

Unsupported

R8

Dependent

UnownedIndependent

Dependent

Response
Type

Local
Government
OfficeDisasterPrevention Plan

Katsurao,
KawauchiFig. 3 Response types of local government offices.

action against earthquake and tsunami, such as return home and escaping into local shelter. However,
it is difficult to grasp such actions of several phases at once and the analysis is fraught withcomplications. So in this study, we only addressed the travel toward the other municipality across theboundary of the resident municipality as the evacuation, by ignoring the previous action due toearthquake and tsunami. And we regarded the end of the evacuation as the time when a resident
escapes into a safe accommodation of the other municipality for the first time.
Evacuation Types of Residents
In order to design the survey, it is essential to assume the evacuation types of residents targeted
for data preparation. In this study, we assumed that the evacuation of a resident is determined by thefollowing elements:(a)start position of evacuation,(b)decision-making of evacuation,(c)transportation for evacuation,(d)municipality of destination for refuge.
Start position of evacuation
Given the action following earthquake and tsunami, such as return home and escaping into local
shelter, most of the residents are likely to start evacuation from home or shelter. So in this study, weclassified the start position of evacuation into two kinds of “home” and “shelter”, and did not consider
other positions such as employment place and relative’s home.
Decision-making of evacuation
When a resident decides the evacuation, there may be the following two patterns: (A) a resident
judges the need for evacuation independently of evacuation order (voluntary); and (B) a resident isforced to evacuate by receiving evacuation order (involuntary). So in this study, we classified thedecision-making of evacuation into two kinds of “voluntary” and “involuntary”. In order to judge if asurvey respondent meets the voluntary evacuation or the involuntary evacuation, it is essential todefine the classification basis. In this study, we classified them by comparing the issue time ofevacuation order targeted at the start position with the departure time from the start position; i.e.:

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(A)
If the departure time is earlier than the issue time, the respondent evacuates “voluntary”,(B)
If the departure time is later than the issue time, the respondent evacuates “involuntary”.
Note that we assumed a resident who starts evacuation from shelter as an involuntary evacuee forsimplicity.
Transportation for evacuation
As one of the methods to travel a long distance between municipalities, public transportation suchas a railroad is usually used. However, as the public one is often shut down after a major earthquake,evacuees have to rely on private transportation such as a family-owned automobile. On the other hand,as to the residents owning no private one, it is being planned that local government office helps with
evacuation by arranging the shared buses. So in this study, we classified the transportation forevacuation into three kinds of “family car”, “other’s car”, and “shared bus”. Note that we assumed thata resident who starts evacuation voluntary before the issue of evacuation order cannot use the shared
bus arranged by the local government office.
Municipality of destination for refuge
As local government office makes residents evacuate to other municipality, it is being planned
that the office requests the accommodation of the residents to the municipality in advance and gives
the residents an instruction on the municipality of destination for refuge. However, all of the residents
may not travel according to such an instruction and a part of the residents is likely to evacuate to amunicipality different from the requested one. So in this study, we classified the municipality ofdestination for refuge into two kinds of “requested” and “unrequested”. Note that a resident who uses
shared bus for evacuation arrives the requested municipality by the office inevitably. However, wecannot apply such a classification based on the request to a resident who starts evacuation voluntary
before the issue of evacuation order.
Time Required for Each Evacuation TypeIn order to evaluate the effectiveness of emergency evacuation, it is essential to formulate thetime required to complete evacuation from an earthquake, which determines the amount of radiation
exposure of an evacuee. So in this study, we regarded the scenario of a resident to complete evacuation
as the following two kinds, according to the classification of decision-making of evacuation:(A) voluntary evacuee,(A1) he percepts the abnormal situation of a nuclear facility after the earthquake,(A2) he thinks whether or not to evacuate and prepares for evacuation,(A3) he travels to other municipality of destination for refuge;and (B) involuntary evacuee,(B1) evacuation order is issued to the position of him,(B2) he receives the evacuation order,(B3) he thinks whether or not to evacuate and prepares for evacuation,(B4) he travels to other municipality of destination for refuge.
Thus the time when a resident completes the evacuation tE is expressed as follows:⎧t A1 + t A 2 + t A3
tE = ⎨⎩t B1 + t B 2 + t B 3 + t B 4(t A1 + t A 2 < t B1 )(t A1 + t A 2 ≥ t B1 )(1)

where tA1, tA2, tA3, tB1, tB2, tB3, and tB4 are respectively the times required for the process A1, A2, A3, B1,
B2, B3, and B4. Note that tA1+tA2 or tB1+tB2+tB3 correspond to the time when a resident leaves home or
shelter.
Outline of Behavior Survey

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In this study, we designed the questions of the survey sheet for the main purpose of measuring thefollowing items:(1)
occurrence frequency of evacuation types,(2)
time required for each process of tA1+tA2, tB2, tB3, and tB4.
Note that we regarded the issue time tB1 as the earlier time when the prime minister or the local
government office issued the evacuation order, and adopted the values described in Table 2. Table 2
shows the main questions of the sheet. As to the questions asking the start position of evacuation andthe transportation for evacuation, we set options in advance. As to the question asking the municipalityof destination for refuge, we adopted the free description where prefecture, city, and town are set to the
response unit. On the other hand, as to the question asking the each time, we also adopted the freedescription where month, day, hour, and minute are set to the response unit.
The outline of the surveys is shown in Table 3. The surveys consist of the following questionnaire
surveys targeted at three municipalities, where a full evacuation of residents to other municipality wasordered: (1) the survey carried out from June 10th, 2011 to June 13th, 2011 at shelters where theTable 2 Main questions of survey sheet.
No.

Question item

Response format

Related measurement item

Q1

Home address before the earthquake

Free description

Decision-making of evacuation

Q2

Damage situation of home just after the earthquake

Single choice－Q3

Departure position for evacuation or deciding position of evacuation

Single choiceStart position of evacuation

Q4

Departure time from the above position

Free description

Decision-making of evacuation, tA1+tA, tB1+tB2+tB3

Q5

Receiving time of evacuation orderFree description

tB1+tB2

Q6

Receiving source of evacuation orderSingle choice－

Q7

Main transportation using for evacuation

Single choiceTransportation for evacuation

Q8

Main road going through for evacuation

Free description－

Q9

Municipality escaping into a safe accommodation for the first time

Free description

Municipality of destination for refuge

Q10Time escaping into a safe accommodation for the first time

Free description

tA1+tA2+tA3, tB1+tB2+tB3+tB4

Table 3 Outline of behavior surveys.
Target municipality

TomiokaPopulation (Household)NarahaKawauchi

16,001 (6,141)

7,700 (2,576)

2,820 (950)Survey sheet

Self-administered questionnaire

Self-administered questionnaire

Self-administered questionnaire

Date of the distribution
Site of the distribution(Municipality)
Method of the distribution

June 10 , 2011
Shelters(Koriyama, Miharu, Otama)
Entrustment to administratorsthNumber of the distributed sheets
Condition of the respondents
Method of the collectionthJuly 9 , 2011
Temporary houses(Koriyama)
Drop into mailboxes

1,300

712

310

Over the age of 18

Representative of each occupant

Representative of each occupantth

Date of the collectionththJune 13 , 2011

October 14 , 2011

July 29 , 2011

Entrustment to administrators

Collection by mailCollection by mail

524

233

88

40.3%

32.7%

28.4%

Number of the collected sheets
Collection ratio
Male

Breakdown(sex, age,
address
could beall confirmed)

thSeptember 23 , 2011
Temporary houses(Iwaki, Aizumisato)
Drop into mailboxes

Female

Total

Male

Female

Total

Male

FemaleTotal

18-24 years

6

4

10

1

2

3

0

0

25-34 years

11

14

25

4

8

12

1

1

2

35-44 years

20

25

45

8

14

22

1

1

2

45-54 years

27

26

53

17

16

33

4

6

10

55-64 years

59

45

104

38

27

65

9

5

14

65-74 years

53

42

95

29

19

48

8

3

11

75 years-

35

35

70

25

13

38

12

1

13

Total

211

191

402

122

99

221

35

17

Collapse ratio

4.5%

5.0%

0

52
0.0%

Inundation ratio

6.0%

7.2%

0.0%

Blackout ratio

91.3%

54.8%

19.2%

Water cut-off ratio

85.1%

86.9%

11.5%

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evacuees from Tomioka town were accommodated; (2) the survey carried out from September 23th,
2011 to October 14th, 2011 at temporary houses where the evacuees from Naraha town wereaccommodated; and (3) the survey carried out from July 9th, 2011 to July 29th, 2011 at temporary
houses where the evacuees from Kawauchi village were accommodated. In the survey for Tomioka
town, we entrusted the distribution and collection of the survey sheets to the administrators of the
shelters, and the survey sheets were distributed to 1,300 evacuees over the age of 18 years old. In thesurveys for Naraha town and Kawauchi village, we dropped 712 sheets and 310 sheets into mailboxesof temporary houses respectively, and collected by mail after having the representative of each
occupant fill out questionnaires. As a result, the number of each survey respondent was 524, 233 and
88 in order of Tomioka, Naraha and Kawaychi, whose collection ratio was in the range of 30 to 40
percent. Of these, the number of each survey respondent whose sex, age, and address before theearthquake could be all confirmed was 424, 221 and 52 in the order, and the mail respondents aged 55
to 64 years old were the most in any surveys. Note that four kinds of ratios in Table 3 are defined asfollows: (1) collapse ratio means the ratio of the respondents who answered “home collapsed perfectlyby the shake” or “home inclined steeply by the shake”; (2) inundation ratio means the ratio of the
respondents who answered “home was destroyed by the tsunami” or “home was inundated by thetsunami”; (3) blackout ratio means the ratio of the respondents who answered “home lost power”; and(4) water cut-off ratio means the ratio of the respondents who answered “water was cut off at home”.

TEDENCY OF EVACUTION TYPES OF RESIDENTS
Fig. 4 (a) shows the breakdown of start position of evacuation answered by the respondents ineach municipality. In any of the municipalities, the respondents who started evacuation from home or
shelter accounted for a large fraction of the total. In both towns of Tomika and Naraha which spreadon the Pacific coast, a certain number of residents had escaped into local shelters due to earthquake
and tsunami in advance. On the other hand, in Kawauchi village, where the damage by the earthquake
was a little because of the inland location, local evacuation before nuclear disaster might hardly takeplace.
Fig. 4 (b) shows the breakdown of voluntary evacuee and involuntary evacuee, as to the
respondents who started evacuation from home. In any towns of Tomika and Naraha located in thevicinity of the stations, most of the residents started evacuation after the issue of evacuation order by
the Prime Minister or the local government offices. On the other hand, as many as half of the
respondents of Kawauchi village judged the need for evacuation independently before the issue, which
is located more than ten kilometers away from the stations. Such a regional difference indicates thepossibility that the residents living in the vicinity of the stations could not receive the information ofRelative’s home
KawauchiWork place

Other
KawauchiHome

Voluntary

Involuntary(n=22)(n=45)
NarahaNarahaShelter(n=218)(n=101)

Tomioka

Tomioka(n=387)(n=161)
0%

20%

40%

60%

80%

0%

100%

(a) Start position of evacuation

20%

40%

60%

80%

100%

(b) Decision-making of evacuation

Fig. 4 Tendency of evacuation types of residents.

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hi
NarahaKawaucOther’s car

Shared bus

Other

Unrequested

Home(n=11)

Kawauchi

Shelter(n=9)(n=75)
Home

NarahaFamily car(n=90)

Requested(n=126)

Tomioka

Shelter(n=123)

TomiokaHome(n=163)(n=144)

0%

20%

40%

60%

80%

100%

0%

(c) Transportation for evacuation

20%

40%

60%

80%

100%

(d) Municipality of destination for refuge

Fig. 4 Tendency of evacuation types of residents.
the accident and concern their safety until the morning on March 12th when the evacuation order was
issued by the administrative agency, because of the invisibleness of radioactive materials and theblackout. On the contrary, the residents far from the ocean might have been able to recognize theseriousness of the event by perceiving the order situation around the stations, because of the smallnessof the earthquake impact. As a result, they could have enough time for thinking whether or not toevacuate until the evacuation order was issued for Kawauchi.
Fig. 4 (c) shows the breakdown of transportation for evacuation by the respondents who started
evacuation after the issue according to start position. In any of the municipalities, most of the
respondents used the private transportation such as family car and other’s car, even where shelter. Thismay be influenced by the fact that any of the offices recommended the residents to evacuate with afamily-owned automobile.
Fig. 4 (d) shows the breakdown of whether or not the municipality of arrival for refuge was theStart Position

Decision-making

Transportation

Home

Voluntary

Family car
Other’s car

Involuntary

Involuntary

Evacuation
Type

Frequency (%)
TomiokaNarahaKawauchi

T1

4.7

5.0

50.0

T2

0.0

1.3

0.0

Requested

T3

38.4

44.7

40.9

Unrequested

T4

3.0

3.1

0.0

Requested

T5

6.0

5.0

0.0

Unrequested

T6

0.0

0.0

0.0

Shared bus

Requested

T7

4.7

2.5

9.1

Family car

Requested

T8

24.1

29.6

0.0

Unrequested

T9

4.7

1.9

0.0

Requested

T10

2.2

3.1

0.0

Unrequested

T11

0.4

0.6

0.0

Requested

T12

11.6

3.1

0.0

Family car

Other’s car

Shelter

Municipalityof Destination

Other’s car

Shared bus

Fig. 5 Evacuation types of residents obtained from the surveys.

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municipality which the resident office requested the accommodation, as to the respondents who started
evacuation with family car after the issue of the order. In any of the municipalities, most of the
respondents escaped into the municipality which the resident office desired. This may be influenced by
the fact that any of the offices referred to the destination to go in the instruction. On the contrary, we
might be able to regard the ratio of the evacuees who cannot follow the instructed destination asaround 10 percent, ignoring the difference in regional characteristics such as road network.
As a result, the evacuation types of residents were obtained as shown in Fig. 5 according tomunicipality. In the respondents of Tomioka and Naraha, the following evacuation types were
dominant:x
T3 (home - involuntary - family car - requested),x
T8 (shelter - involuntary - family car - requested),
and the occurrence tendency of the other types was also similar. On the other hand, the responses of
Kawauchi residents concentrated on the following evacuation types:x
T1 (home - voluntary - family car),x
T3 (home - involuntary - family car - requested).

REQUIRED TIME OF TYPE 3 NARAHA RESIDENTS
In this chapter, we focused on the Naraha respondents whose evacuation type were T3 (home involuntary - family car - requested), and analyzed the time required for each process of that type.
Fig. 6 shows the frequency distribution of the departure time from home (tB1+tB2+tB3), where thehorizontal axis indicates the time from 6:00 AM to 12:00 PM on March 12th, and the left and rightvertical axes are respectively relative frequency and cumulative relative frequency. And dotted lines
indicate the occurrence time of the main events of station situations and protection measures. The
relative frequency distribution showed the single-peaked distribution with the bias to left side, whose
peak was 9:00 AM to 10:00 AM on March 12th. Most of the respondents started home within
one-to-three hours after the issue of full-scale evacuation order by the office, and such generation ofevacuees roughly settled in the evening. However, the cumulative relative frequency was estimated to
be about 80 percents by four hours after the issue by the office and be about 97 percents by 12:00 PM
on March 12th.
(n=71)

50

Relative Frequency (%)

(2)

(3)

80

Cumulative

30

60(1) Full-scale evacuation orderby Naraha office(2) Hydrogen Explosion at 1F(3) R=10km from 2F evacuation orderby the Prime Minister

20

40

Relative

20

10

00

06

93

6
12

9
15

12
18

15
21

18
24

Cumulative Relative Frequency (%)

(1)

40

100

0

(h)
Departure TimeDeparturetB1+ tB2+ tTime
B3 (3/12 6:00-24:00)

Fig. 6 Distribution of departure time from home (Type 3 Naraha respondents).

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Fig. 7 shows the breakdown of the receiving source of evacuation order. Outdoor speakercontributed the most for the respondents staying home to receive the evacuation order. Including the
respondents who answered PR car or local officer, the administrative approach from Naraha office wasmore than 80 percents. The mass media such as TV and radio could not function effectively for
informing the order immediately. One of the contributing factors of this is thought to be unavailable
for the equipment because of the blackout as show in Table 3.
As to the respondents who received the evacuation order from the outdoor speaker, Fig. 8 shows
the frequency distribution of the following time: (a) the required time from when the office issued theorder till when the respondent received the order (propagation time tB2); and (b) the required time fromwhen the respondent received the order till when the respondent left the home (preparation time tB3).
The propagation time showed the double-peaked distribution whose peaks were 0-to-0.5 hours and1-to-1.5 hours. Such a difference in the required time to obtain the order may imply the existence ofthe residents who could be easy to listen to the announcement from the speaker and those who could
not. On the other hand, the preparation time also showed the double-peaked distribution whose peaks

PR car (8%)

Local officer (11%)

Neighborhood (2%)

Outdoor speaker(66%)

Naraha(n=64)
Naraha(n=64)

TV (5%)

Radio (2%)

0%

20%

Other (8%)

40%

60%

80%

100%

Fig. 7 Receiving source of evacuation order (Type 3 Naraha respondents).
(n=34)

50
μB2=1.279
σB2=0.868

30

20

30

20

10

10

0

μB3=0.874
σB3=0.582

40
Relative Frequency (%)

Relative Frequency (%)

40(n=34)

50

0

1

2

3

4

5

0

6

0

1

2

3

4

5

6

Preparation Time t B3 (h)Propagation Time t B2 (h)(a) Propagation time(b) Preparation time

Fig. 8 Distribution of propagation time and preparation time (Type 3 Naraha respondents).

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were 0-to-0.5 hours and 1-to-1.5 hours. This may imply the existence of the residents who left homewith fear immediately after listening to the order and those who could not recognize the seriousness ofthe situation immediately.
Fig. 9 shows the distribution of travel time (tB4) according to departure time from home, when theevacuees generated remarkably. Note that this travel time corresponds to the time to reach a safe
accommodation in Iwaki city, where Naraha office instructed to go for refuge. It took as much time asfive-to-seven hours on average to reach the first destination for refuge. As the distance between
Naraha office and Iwaki office along the main roads is roughly 35 kilometers, the average travel speed
was estimated to be 5-to-7 kilometers per hour. This may imply the occurrence of traffic jams on
evacuation roads.

16
14

μB4=5.43
σB4=2.55

μB4=5.05
σB4=2.41

μB4=4.73
σB4=2.13

μB4=6.83
σB4=2.21

3.12 8-9h

3.12 9-10h

3.12 10-11h

3.12 11-12h

TravelTime
TravelTimetB4(h)
(h)

12
10
8
6
4
2
0
Departure Time (3/12 8:00-12:00 AM)

Fig. 9 Distribution of travel time according to departure time (Type3 Naraha respondents).

CONCLUSIONSIn this study, we clarified a part of the actual situation in the Fukushima Emergency Event interms of evacuation types of residents and required time for involuntary evacuation, by counting theobtained data from the questionnaire surveys. However, more detail analysis on the following things isessential: (1) information contact and reaction of local government offices requiring emergency
evacuation; and (2) the governing factors of required time for each behavior of a resident.

REFERENCES
Nuclear and Industrial Safety Agency. (2011). “Report on seismic damage.” (in Japanese).
Nuclear Safety Commission of Japan. (2010). “Preparations for disaster at nuclear facilities.” (inJapanese).
Umemoto, M., Ishigami T and Kobayashi K. (2002). “The inhabitants’ Reaction after Contact with
Disaster Information at the JCO Critically Accident.” Journal of Social Safety Science, No. 4,
231-240 (in Japanese).
Umemoto, M. (2011). “A Study on Citizens’ Choices of Means of Transportation for Long Distance
Evacuation Extending to the Next Prefecture.” Journal of the City Planning Institute of Japan, Vol.
46, No. 2, 131-141 (in Japanese).

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