[2013-06-21] NRC Responses to Public Comments Japan ... · Response: Since the flood hazard reev...
Transcript of [2013-06-21] NRC Responses to Public Comments Japan ... · Response: Since the flood hazard reev...
P
age
1 of
70
DR
AFT
NR
C R
espo
nses
to P
ublic
Com
men
ts [2
013-
06-2
1]
Japa
n Le
sson
s-Le
arne
d Pr
ojec
t Dire
ctor
ate
Inte
rim S
taff
Gui
danc
e JL
D-IS
G-2
013-
01:
Gui
danc
e fo
r Ass
essm
ent o
f Flo
odin
g H
azar
ds D
ue to
D
am F
ailu
re
(Doc
ket I
D N
RC
-201
3-00
73)
AD
AM
S A
cces
sion
No.
MLX
XX
X
MO
NTH
201
3
P
age
2 of
70
I. In
trod
uctio
n Th
is d
ocum
ent p
rese
nts
the
U.S
. Nuc
lear
Reg
ulat
ory
Com
mis
sion
(NR
C) s
taff’
s re
spon
ses
to c
omm
ents
rece
ived
on
the
Dra
ft in
terim
sta
ff gu
idan
ce (I
SG
) doc
umen
t, “J
LD-IS
G-2
013-
01: G
uida
nce
for A
sses
smen
t of F
lodi
ng H
azar
ds D
ue to
Dam
Fai
lure
.” T
he
draf
t IS
G w
as p
ublis
hed
in th
e Fe
dera
l Reg
iste
r on
Apr
il 25
, 201
3 (7
8 FR
244
39).
The
pub
lic c
omm
ent p
erio
d cl
osed
on
May
28,
201
3; th
ere
wer
e no
late
com
men
ts re
ceiv
ed.
Com
men
t sub
mis
sion
s on
the
draf
t doc
umen
t are
ava
ilabl
e el
ectro
nica
lly a
t the
NR
C’s
Ele
ctro
nic
Rea
ding
Roo
m a
t ht
tp://
ww
w.n
rc.g
ov/re
adin
g-rm
/ada
ms.
htm
l . F
rom
this
pag
e, th
e pu
blic
can
gai
n en
try in
to th
e A
genc
ywid
e D
ocum
ents
Acc
ess
and
Man
agem
ent S
yste
m (A
DA
MS
), w
hich
pro
vide
s te
xt a
nd im
age
files
of N
RC
's p
ublic
doc
umen
ts.
This
com
men
t res
olut
ion
docu
men
t is
also
ava
ilabl
e el
ectro
nica
lly a
t the
NR
C’s
Ele
ctro
nic
Rea
ding
Roo
m u
nder
AD
AM
S A
cces
sion
N
o. M
L13X
XX
XX
.
The
final
ISG
can
be
foun
d in
AD
AM
S a
t Acc
essi
on N
o. M
L13X
XX
XX
.
II.
Com
men
t sub
mis
sion
s Th
e N
RC
rece
ived
[Num
ber]
(X) c
omm
ent s
ubm
issi
ons.
The
NR
C-d
esig
nate
d id
entif
ier f
or e
ach
uniq
ue c
omm
ent s
ubm
issi
on, t
he
nam
e of
the
subm
itter
, the
sub
mitt
er’s
affi
liatio
n (if
any
), an
d th
e A
DA
MS
Acc
essi
on N
umbe
r is
prov
ided
bel
ow.
Sum
mar
y Ta
ble
Nam
e A
ffilia
tion
AD
AM
S
Acc
essi
on N
o.
Kar
in M
. Hol
liste
r S
arge
nt &
Lun
dy, L
LC
ML1
3XX
XX
X
Mar
k M
oens
sens
W
estin
ghou
se E
lect
ric C
ompa
ny
ML1
3XX
XX
X
Jam
es H
. Rile
y N
ucle
ar E
nerg
y In
stitu
te
ML1
3XX
XX
X
J. W
. She
a Te
nnes
see
Val
ley
Aut
horit
y M
L13X
XX
XX
K. C
anav
an
Ele
ctric
Pow
er R
esea
rch
Inst
itute
M
L13X
XX
XX
M. M
cCan
n ??
? M
L13X
XX
XX
P
age
3 of
70
III.
Publ
ic C
omm
ents
and
NR
C R
espo
nse
P
age
4 of
70
Tabl
e 1:
Com
men
ts
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
1.
[K. H
ollist
er]
Loca
tion:
Var
ious
Com
men
t: In
the T
erms
and D
efinit
ions s
ectio
n, pr
ovide
a de
finitio
n for
each
re
servo
ir/poo
l leve
l disc
usse
d in t
he do
cume
nt. F
or ex
ample
, Sec
tion
4.2.2.
2 disc
usse
s the
"max
imum
norm
al po
ol ele
vatio
n," S
ectio
n 5.6
discu
sses
"max
imum
norm
al op
erati
ng ("
full-p
ool")
and a
vera
ge
rese
rvoir l
evels
," an
d Sec
tion 6
.2.2 d
iscus
ses "
norm
al po
ol ele
vatio
n (in
vert
of the
high
est o
utlet
or sp
illway
)" an
d "top
of da
m/ma
ximum
high
po
ol."
Plea
se in
clude
a de
finitio
n for
thes
e lev
els an
d any
othe
rs tha
t are
inc
luded
in th
e fina
l ver
sion o
f the D
am F
ailur
e ISG
.
Resp
onse
: Ma
ximum
norm
al po
ol ele
vatio
n is d
efine
d as t
he
eleva
tion c
orre
spon
ding t
o the
top o
f the a
ctive
sto
rage
. Th
e ave
rage
rese
rvoir l
evel
(ave
rage
pool
eleva
tion)
is
the 50
% ex
ceed
ance
dura
tion p
ool le
vel
calcu
lated
using
aver
age d
aily w
ater l
evels
for t
he
perio
d of r
ecor
d. “fu
ll poo
l”, “n
orma
l poo
l”, “m
axim
um hi
gh po
ol” ar
e no
long
er us
ed in
the d
ocum
ent.
Actio
n:
1)
defin
itions
adde
d to a
ppro
priat
e sec
tions
to
the T
erms
and d
efinit
ions s
ectio
n (un
der s
torag
e)
2)
“full p
ool” i
s no l
onge
r use
d in t
he do
cume
nt
2.
[M. M
oens
sens
] Lo
catio
n: G
ener
al Co
mm
ent:
In ge
nera
l, it d
oes n
ot ap
pear
that
there
is a
direc
t off r
amp o
r red
uced
pa
th for
the i
nstan
ce w
here
a da
m, le
vee,
emba
nkme
nt, et
c. is
owne
r co
ntroll
ed an
d lice
nsed
by th
e NRC
as a
seism
ic ca
tegor
y I st
ructu
re.
Thes
e stru
cture
s wer
e orig
inally
quali
fied i
n the
safet
y ana
lysis
repo
rt su
bmitte
d with
the l
icens
ee's
appli
catio
n and
verifi
ed by
the N
RC sa
fety
evalu
ation
repo
rt. A
dire
ct sta
temen
t(s) s
hould
be in
clude
d in t
he IS
G to
Resp
onse
: Fo
r ons
ite w
ater c
ontro
l stru
cture
s suc
h as d
ams,
levee
s, im
poun
dmen
ts, et
c. (in
cludin
g seis
mic
categ
ory I
, but
exclu
ding t
anks
), fai
lure d
ue to
hy
drolo
gic or
sunn
y-day
mec
hanis
ms ar
e to b
e ev
aluate
d as p
art o
f the R
2.1 F
loodin
g Ree
valua
tion.
Me
thods
acce
ptable
to th
e staf
f for t
his pu
rpos
e are
de
scrib
ed in
this
ISG.
Seis
mic f
ailur
e of s
uch
P
age
5 of
70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
clear
ly sta
te wh
at is
requ
ired f
or se
ismic
categ
ory I
stru
cture
s. Cu
rrentl
y, the
ISG
does
not m
ake a
ny di
recti
on m
entio
n to t
he te
rm
seism
ic ca
tegor
y I.
struc
tures
falls
unde
r the
scop
e of th
e R2.1
Seis
mic
Reev
aluati
on.
Actio
n:
Text
adde
d to S
ectio
n 2.1
(scop
e) to
clar
ify th
is po
sition
.
3.
[M. M
oens
sens
] Lo
catio
n: P
age 1
, Sec
tion 1
Co
mm
ent:
Add "
of' af
ter th
e wor
d "co
mbina
tion"
in th
e sec
ond p
arag
raph
Resp
onse
: Ca
nnot
find t
his w
ord i
n 2nd
para
grap
h. Co
mbina
tion
is us
ed in
3rd pa
ragr
aph,
but is
alre
ady f
ollow
ed by
“o
f”.
Actio
n: N
o cha
nge t
o tex
t
4.
[M. M
oens
sens
] Lo
catio
n: P
age 1
, Sec
tion 1
.1 Co
mm
ent:
Is no
t it m
ore r
ealis
tic to
only
utiliz
e this
ISG
rathe
r tha
n refe
rring
back
to
Reg.
1.59 w
hich i
s ver
y muc
h outd
ated?
Resp
onse
: Th
is IS
G su
pplem
ents
and c
larifie
s othe
r NRC
gu
idanc
e tha
t disc
usse
s dam
failu
re su
ch as
RG-
1.59.
Actio
n: N
o cha
nge t
o tex
t
5.
[M. M
oens
sens
] Lo
catio
n: P
age 2
, Sec
tion 1
.1 Co
mm
ent:
If the
re ar
e diffe
renc
es on
a ce
rtain
issue
betw
een t
he di
ffere
nt gu
idanc
e, wh
ich gu
idanc
e sho
uld be
follo
wed?
The
mos
t strin
gent?
Mo
reov
er, if
the L
icens
ee al
so ow
ns a
dam,
does
it ne
ed to
be in
co
mplia
nce w
ith al
l regu
lation
s or o
nly th
e nuc
lear o
nes?
Resp
onse
: In
gene
ral, t
his IS
G sh
ould
be fo
llowe
d if th
ere a
re
differ
ence
s in N
RC gu
idanc
e. Ho
weve
r, lic
ense
es
are n
ot re
quire
d to f
ollow
NRC
guida
nce.
As st
ated i
n sec
tion 1
.1, th
is gu
idanc
e sho
uld in
no
way s
uper
sede
or be
used
in lie
u of g
uidan
ce
deve
loped
by an
y age
ncy t
hat o
wns,
oper
ates o
r re
gulat
es th
e dam
(s) of
inter
est.
P
age
6 of
70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
The p
urpo
se of
this
ISG
is to
prov
ide gu
idanc
e in
estim
ating
the c
onse
quen
ces o
f pote
ntial
dam
failur
es in
term
s of fl
ood h
azar
ds at
the N
PP.
Actio
n: N
o cha
nge t
o tex
t
6.
[M. M
oens
sens
] Lo
catio
n: P
age 4
, Sec
tion 1
.3.2
Com
men
t: Do
es N
RC re
quire
a P.
E en
ginee
r cer
tifica
tion f
or br
each
analy
sis (b
ut no
t the s
creen
ing an
d sim
plifie
d ana
lyses
)? If
so, d
oes h
e/she
need
to
have
the P
.E fr
om th
e stat
e whe
re th
e dam
is lo
cated
?
Resp
onse
: Si
nce t
he flo
od ha
zard
reev
aluati
on re
ports
are t
o be
subm
itted u
nder
“Oath
and A
ffirma
tion”
, it is
ex
pecte
d tha
t the t
echn
ical w
ork b
e per
forme
d by
comp
etent
profe
ssion
als. H
owev
er N
RC do
es no
t ha
ve ex
plicit
requ
ireme
nts re
gard
ing lic
ensu
re. O
ther
state
or fe
dera
l age
ncies
with
juris
dictio
n for
dam
safet
y may
have
such
requ
ireme
nts.
Actio
n: N
o cha
nge t
o tex
t
7.
[M. M
oens
sens
] Lo
catio
n: P
age 4
, Sec
tion 1
.3.2
Com
men
t: Se
cond
para
grap
h, do
es th
is IS
G re
comm
end u
sing t
he cu
rrent
NOAA
hy
drom
eteor
ologic
al re
ports
for d
am fa
ilure
analy
sis, s
ome o
f whic
h da
te ba
ck to
the l
ate 19
70's
but a
re st
ill the
"cur
rent"
repo
rt for
a re
gion?
Resp
onse
: Th
e NOA
A/NW
S hy
drom
eteor
ologic
al re
ports
(H
MRs)
are t
he m
ost c
ompr
ehen
sive i
nform
ation
on
extre
me ra
infall
estim
ate av
ailab
le at
this t
ime.
Ho
weve
r, du
e to t
he ag
e of th
ese r
epor
ts (e
.g. H
MR-
51 w
as pu
blish
ed in
1978
), the
licen
see s
hould
ex
ercis
e due
dilig
ence
and e
xami
ne th
e rec
ord o
f ex
treme
stor
ms in
the r
egion
of in
teres
t to pr
ovide
as
sura
nce t
hat th
e HMR
estim
ates a
re st
ill va
lid.
Actio
n:
Follo
wing
text
adde
d to S
ectio
n 1.3.
2: Ex
isting
estim
ates f
or de
sign s
torms
and f
loods
(e.g.
, PM
P an
d PMF
) in th
e reg
ion of
inter
est d
evelo
ped b
y
P
age
7 of
70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
feder
al, st
ate or
othe
r age
ncies
may
be us
ed.
Howe
ver,
some
of th
ese r
epor
ts ma
y be q
uite o
ld (e
.g. th
e NOA
A/NW
S Hy
drom
eteor
ologic
al Re
port
51
for th
e Eas
tern U
.S. w
as pu
blish
ed in
1978
). T
he
licen
see s
hould
exer
cise d
ue di
ligen
ce an
d exa
mine
the
reco
rd of
extre
me st
orms
and f
loods
in th
e reg
ion
of int
eres
t to pr
ovide
assu
ranc
e tha
t the e
xistin
g es
timate
s are
still
valid
.
8.
[M. M
oens
sens
] Lo
catio
n: P
age 4
, Sec
tion 1
.3.2
Com
men
t: If f
lood l
evels
do no
t rea
ch th
e site
, doe
s the
licen
see s
till ne
ed to
ev
aluate
the t
rans
port
of se
dimen
ts an
d deb
ris?
Resp
onse
: Se
dimen
t tran
spor
t sho
uld be
cons
idere
d in t
he
analy
sis. Ig
norin
g sed
imen
t dep
ositio
n may
resu
lt in
unde
resti
mates
of w
ater le
vel e
levati
ons.
Co
nver
sely,
igno
ring s
edim
ent e
rosio
n may
mea
n tha
t pote
ntiall
y dan
gero
us sc
ourin
g aro
und
struc
tures
is ig
nore
d. If f
lood l
evels
do no
t rea
ch th
e site
, then
wate
rbor
ne
debr
is im
pacts
wou
ld no
t nee
d to b
e con
sider
ed at
the
site.
How
ever
, wate
rbor
ne de
bris
impa
cts on
an
upstr
eam
dam
may s
till be
germ
ane.
Secti
on 4.
2.8 of
the r
evise
d ISG
prov
ides m
ore d
etail
on es
timati
ng w
aterb
orne
debr
is im
pacts
. De
tailed
guida
nce o
n sed
imen
t tran
spor
t mod
eling
is
beyo
nd th
e sco
pe of
this
ISG,
but S
ectio
n 9.3
of the
re
vised
guide
prov
ed re
feren
ces.
In m
any
case
s,
sim
plifi
ed c
onse
rvat
ive
estim
ates
for e
rosi
on a
nd
sedi
men
tatio
n m
ay b
e us
ed in
lieu
of d
etai
led
anal
ysis
..
P
age
8 of
70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Actio
n:
Secti
on 9.
3 of h
as be
en ad
ded t
o the
revis
ed gu
ide.
9.
[M. M
oens
sens
] Lo
catio
n: P
age
8, S
ectio
n 1.
4.2
Com
men
t: Ad
d "is"
after
"it"
to re
ad "i
t is ac
cepta
ble"
Resp
onse
: Se
ction
1.4 h
as be
en re
orga
nized
and t
his ph
rase
is
no lo
nger
used
. Ac
tion:
No
chan
ge to
text.
10.
[M. M
oens
sens
] Lo
catio
n: P
age
10, S
ectio
n 1.
5.3
Co
mm
ent:
On th
e sixt
h line
of th
e firs
t bull
et, "d
evelo
pi" is
miss
pelle
d
Resp
onse
: Ac
tion:
Sp
elling
corre
cted.
11.
[M. M
oens
sens
] Lo
catio
n: P
age
11, S
ectio
n 1.
6
Com
men
t: Th
e sec
tion s
tates
that,
"Deta
ils of
dam
brea
ch m
odeli
ng ar
e disc
usse
d in
ISG
Secti
on 7.
" This
shou
ld be
Sec
tion 8
Resp
onse
: Ac
tion:
Se
ction
cros
s refe
renc
e cor
recte
d,
12.
[M. M
oens
sens
] Lo
catio
n: P
age
11, S
ectio
n 1.
6
Com
men
t: Th
e sec
tion s
tates
that,
"Deta
ils of
flood
routi
ng ar
e disc
usse
d in I
SG
Secti
on 9.
" This
shou
ld be
Sec
tion 1
0
Resp
onse
: Ac
tion:
Se
ction
cros
s refe
renc
e cor
recte
d
13.
[M. M
oens
sens
] Lo
catio
n: P
age
11, S
ectio
n 1.
6
Com
men
t: Re
spon
se:
In the
revis
ed IS
G, op
erati
onal
failur
es an
d
P
age
9 of
70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
The s
ectio
n des
cribe
s the
orga
nizati
on of
the g
uidan
ce bu
t doe
s not
desc
ribe S
ectio
n 7, "
Oper
ation
al Fa
ilure
s and
Con
trolle
d Rele
ases
." co
ntroll
ed re
lease
s are
disc
usse
d in s
ectio
n 4.2.
7 Ac
tion:
No
chan
ges t
o tex
t in se
ction
1.6
14.
[M. M
oens
sens
] Lo
catio
n: P
age
24, S
ectio
n 3.
2 Co
mm
ent:
Do yo
u inc
lude "
all" d
ams (
items
1.a a
nd 2.
b) or
only
"all"
dams
that
are
cons
eque
ntial
(i.e., a
fter s
creen
ing)?
The
text
contr
adict
s wha
t is on
Fig
ure 1
0.
Resp
onse
: Th
e figu
re 10
is co
rrect.
Inco
nseq
uenti
al da
ms m
ay
be ex
clude
d befo
re im
pleme
nting
the s
creen
ing
proc
edur
es di
scus
sed.
Actio
n:
Clar
ificati
on ad
ded t
o tex
t for s
creen
ing st
eps 1
.a an
d 2.b
and 3
.b
15.
[M. M
oens
sens
] Lo
catio
n: P
ages
33,
38,8
1; S
ectio
ns 4
.2.2
.1,4
.2.7
,10
Com
men
t: Do
es N
RC re
comm
end t
he ut
ilizati
on of
2D / 3
D mo
delin
g soft
ware
pa
ckag
e suc
h as F
LO-2
D or
Delf
t3D in
stead
of H
EC-R
AS to
acco
unt fo
r se
dimen
t pro
ducti
on an
d tra
nspo
rt, m
ud flo
ws, a
nd de
bris
trans
port?
Resp
onse
: Th
e nee
d to a
ddre
ss m
ud flo
ws ha
s bee
n rem
oved
fro
m the
ISG.
Ce
rtain
wide
ly-us
ed m
odeli
ng so
ftwar
e pac
kage
s are
me
ntion
ed in
the I
SG fo
r illus
trativ
e pur
pose
s, bu
t the
NRC
does
not r
ecom
mend
spec
ific so
ftwar
e pa
ckag
es. I
n gen
eral,
hydr
ologic
and h
ydra
ulic
simula
tion m
odels
acce
pted i
n stan
dard
engin
eerin
g pr
actic
e by F
eder
al ag
encie
s and
othe
r auth
oritie
s re
spon
sible
for si
milar
desig
n con
sider
ation
s may
be
used
. Ac
tion:
La
ngua
ge si
milar
to th
e pre
cedin
g par
agra
ph ha
s
P
age
10 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
been
adde
d to t
he re
vised
ISG
secti
on 1.
1 (Pu
rpos
e)
16.
[M. M
oens
sens
] Lo
catio
n: P
age
37, S
ectio
n 4.
2.4
Com
men
t: Th
ere a
ppea
rs to
be an
extra
bulle
t at th
e end
of th
e Staf
f pos
ition i
n Se
ction
4.2.4
. Is th
is an
extra
bulle
t or w
as an
addit
ional
staff p
ositio
n sta
temen
t sup
pose
d to b
e loc
ated h
ere?
Resp
onse
: Ac
tion:
Ex
tra bu
llet r
emov
ed.
17.
[M. M
oens
sens
] Lo
catio
n: P
age
38, S
ectio
n 4.
2.7
Com
men
t: Ca
n the
licen
see u
tilize
the R
USLE
meth
od to
iden
tify th
e pote
ntial
for
eros
ion in
the w
atersh
ed?
Resp
onse
: Th
e RUS
LE m
ethod
was
deve
loped
to es
timate
er
osion
for a
gricu
ltura
l app
licati
ons.
The
datab
ase
used
to de
velop
the m
ethod
was
base
d on
agric
ultur
al plo
t-sca
le sit
es w
ith di
sturb
ed so
ils. In
ge
nera
l, it w
ould
not b
e app
licab
le to
the la
rge
water
shed
s of in
teres
t in th
is IS
G wi
thout
signif
icant
modif
icatio
n. H
owev
er, th
e req
uirem
ent to
cons
ider
mud f
lows h
as be
en re
move
d fro
m the
ISG,
so th
is co
mmen
t is no
long
er re
levan
t. Ac
tion:
Th
e sec
tion o
n mud
flows
has b
een r
emov
ed.
18.
[M. M
oens
sens
] Lo
catio
n: P
age
40, S
ectio
n 4.
2.7.
2 Co
mm
ent:
The f
irst p
arag
raph
after
Tab
le 3 r
efere
nces
the 2
005 v
ersio
n of
ASCE
/SEI
7-05
. The
re is
a mo
re re
cent
versi
on, A
SCE/
SEI 7
-10.
Resp
onse
: Th
e meth
odolo
gy de
scrib
ed in
the m
ost r
ecen
t ve
rsion
(ASC
E/SE
I 7-1
0) di
ffers
some
what
from
the
older
meth
od in
the I
SG. N
RC st
aff ha
ve re
viewe
d the
newe
r meth
odolo
gy an
d fou
nd it
to be
ac
cepta
ble.
Actio
n:
P
age
11 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
This
secti
on ha
s bee
n mod
ified t
o refl
ect th
e me
thodo
logy i
n the
mos
t rec
ent v
ersio
n of th
e ACS
E sta
ndar
d.
19.
[M. M
oens
sens
] Lo
catio
n: P
age
40, S
ectio
n 4.
2.7.
2 Co
mm
ent:
USAC
E ER
DC/C
RREL
TR-
02-2
evalu
ated s
ever
al dif
feren
t meth
ods o
f es
timati
ng de
bris
loadin
g for
logs
. It co
nclud
ed th
at "a
ll thr
ee
appr
oach
es ca
n be d
erive
d fro
m a s
ingle-
degr
ee-o
f-fre
edom
mod
el of
the co
llision
and a
re eq
uivale
nt." T
here
fore,
it is r
ecom
mend
ed th
at the
NA
ASTR
A (H
ighwa
y Brid
ge D
esign
Spe
cifica
tion)
and A
ASHT
O (L
RFD
Bridg
e De
sign
Spec
ificat
ions)
meth
ods a
lso be
refer
ence
d in S
taff
Posit
ion bu
llet 3
.
Resp
onse
: Th
e USA
CE re
port
show
s tha
t the m
ethod
s are
eq
uivale
nt for
a ce
rtain
rang
e of v
elocit
ies an
d und
er
certa
in as
sump
tions
rega
rding
the s
tiffne
ss of
the
debr
is an
d stru
cture
impa
cted.
If the
NAS
STRA
me
thod (
work
ener
gy m
ethod
) or t
he A
ASHT
O me
thod (
conta
ct sti
ffnes
s meth
od)
are u
sed,
the
licen
see s
hould
justi
fy tha
t the r
esult
s are
equiv
alent
or m
ore c
onse
rvativ
e tha
n the
impu
lse m
omen
tum
appr
oach
outlin
ed in
the A
SCE
stand
ard.
Actio
n:
No ch
ange
to te
xt.
20.
[M. M
oens
sens
] Lo
catio
n: P
age
43, S
ectio
n 5
Com
men
t: Th
ere i
s a se
ction
cros
s refe
renc
e tha
t app
ears
to ha
ve be
en lo
st at
the
end o
f the l
ast s
enten
ce in
the t
hird p
arag
raph
.
Resp
onse
: Cr
oss r
efere
nce i
s to s
ectio
n 5.6
Actio
n:
Adde
d cro
ss re
feren
ce to
secti
on 5.
6
21.
[M. M
oens
sens
] Lo
catio
n: P
age
43, S
ectio
n 5.
1.1
Com
men
t: W
ill NR
C ac
cept
a reg
ional
PSHA
stud
y or a
nothe
r stud
y fro
m a
neigh
borin
g site
or is
it a "
must"
to co
nduc
t a si
te-sp
ecific
PSH
A as
part
Resp
onse
: A
site-
spec
ific an
alysis
shou
ld be
perfo
rmed
. Ac
tion:
No
chan
ge to
text.
P
age
12 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
of the
dam
failur
e ana
lysis
due t
o seis
mic e
vent?
22.
[M. M
oens
sens
] Lo
catio
n: P
age
46, S
ectio
n 5.
2.1
Com
men
t: In
the la
st se
ntenc
e of th
e 3rd
para
grap
h, "d
owns
tream
" is r
epea
ted.
One o
f the i
nstan
ces s
hould
prob
ably
be up
strea
m.
Resp
onse
: Ac
tion:
Re
peate
d wor
d dele
ted.
23.
[M. M
oens
sens
] Lo
catio
n: P
age
52, S
ectio
n 5.
4.1
Com
men
t: In
staff p
ositio
n bull
et 1,
the te
rm "U
HRS"
is us
ed, b
ut no
t pre
vious
ly de
fined
. Sho
uld th
is ter
m be
UHS
, as d
efine
d in S
ectio
n 5.7.
1.4?
Resp
onse
: Sh
ould
be U
HS
Actio
n:
Text
corre
cted.
24.
[M. M
oens
sens
] Lo
catio
n: P
age
52, S
ectio
n 5.
4.1
Com
men
t: St
aff po
sition
bulle
t 1 st
ates t
hat, "
...(ba
sed o
n the
UHR
S an
d ac
coun
ting f
or si
te am
plific
ation
) as d
escri
bed i
n Sec
tion 5
.4.1."
The
re
feren
ce to
Sec
tion 5
.4.1 s
hould
prob
ably
be ch
ange
d to S
ectio
n 5.7
.1.4.
Resp
onse
: Re
feren
ce is
to 5.
3.1
Actio
n:
Refer
ence
corre
cted.
25.
[M. M
oens
sens
] Lo
catio
n: P
age
52, S
ectio
n 5.
4.1
Com
men
t: In
staff p
ositio
n bull
et 2,
the te
rm "U
HS" i
s use
d, bu
t not
prev
iously
de
fined
. It is
defin
ed la
ter in
Sec
tion 5
.7.1.4
.
Resp
onse
: Re
peat
of pr
eviou
s com
ment.
Ac
tion:
No
chan
ge
26.
[M. M
oens
sens
] Lo
catio
n: P
age
52, S
ectio
n 5.
4.1
Com
men
t: Re
spon
se:
Repe
at of
prev
ious c
omme
nt
P
age
13 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
The l
ast s
enten
ce of
Staf
f pos
ition b
ullet
1 stat
es th
at, ".
..in lig
ht of
the
UHS
deve
loped
in S
ectio
n 5.4.
1 inc
luding
effec
ts of
..." T
he re
feren
ce to
Se
ction
5.4.1
shou
ld pr
obab
ly be
chan
ged t
o Sec
tion 5
.7.1.4
.
Actio
n:
No ch
ange
27.
[M. M
oens
sens
] Lo
catio
n: P
age
67, S
ectio
n 6.
1.3
Com
men
t: Th
e tex
t of th
e Lev
ee se
ction
was
remo
ved b
ased
on pa
st co
mmen
ts bu
t the s
ectio
n hea
der r
emain
s. It i
s rec
omme
nded
that
a stat
emen
t be
adde
d und
er th
e hea
der t
hat S
unny
Day
Fail
ure i
s not
appli
cable
to
levee
s sinc
e the
y are
not n
orma
lly lo
aded
.
Resp
onse
: Ac
tion:
Se
ction
head
er re
move
d.
28.
[M. M
oens
sens
] Lo
catio
n: P
age
68, S
ectio
n 6.
2 &
6.2.
2 Co
mm
ent:
On P
age 6
8 the
re ar
e two
insta
nces
of w
here
Sec
tion 7
is re
feren
ced.
Thes
e sho
uld be
refer
ence
s to S
ectio
n 8.
Resp
onse
: Ac
tion:
Cr
oss r
efere
nce u
pdate
d.
29.
[M. M
oens
sens
] Lo
catio
n: P
age
79, S
ectio
n 9
Com
men
t: Th
e sec
ond w
ord o
f the 3
rd pa
ragr
aph s
hould
be "f
rom,
" not
"form
."
Resp
onse
: Ac
tion:
Te
xt co
rrecte
d.
30.
[M. M
oens
sens
] Lo
catio
n: P
age
82, S
ectio
n 10
.1.2
Co
mm
ent:
With
resp
ect to
the l
ast p
arag
raph
, ther
e is a
state
ment
abou
t the u
se of
1D
flood
mod
els in
flat-ly
ing to
pogr
aphy
. The
para
grap
h doe
s not
direc
tly st
ate th
at 1D
mod
eling
shou
ld no
t be u
sed i
n this
case
. 1D
mode
ling t
ools
are a
poor
choic
e of m
odeli
ng to
ols fo
r this
scen
ario.
Lo
w re
lief a
reas
whe
re di
stribu
tary f
low m
ay oc
cur s
hould
rely
on 2D
(at
Resp
onse
: Te
xt sta
tes th
at, in
this
case
, a 2D
mod
el wi
ll bett
er
simula
te flo
ws in
flat to
pogr
aphy
. Ac
tion:
No
chan
ge to
text.
P
age
14 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
minim
um) m
odels
to de
al wi
th the
comp
lexity
of no
n-ch
anne
lized
flow.
Th
ere i
s a tr
emen
dous
amou
nt of
acad
emic
rese
arch
on th
is, an
d it is
n't
clear
why
1 D
mode
ls ar
e still
used
in th
ese a
reas
. The
ISG
shou
ld tak
e a f
irm po
sition
for t
he ap
plica
bility
of 1D
versu
s 2D
/ 3D
mode
ling.
31.
[M. M
oens
sens
] Lo
catio
n: P
age
83, S
ectio
n 10
.2
Com
men
t: Th
is se
ction
ambig
uous
ly re
feren
ces t
he m
odels
used
in H
EC-R
AS. It
is
reco
mmen
ded t
o stat
e dire
ctly t
hat H
EC-R
AS is
appr
opria
te wh
en it
is de
termi
ned t
hat a
one-
dimen
siona
l flow
mod
el is
suita
ble.
Resp
onse
: Th
e disc
ussio
n in q
uesti
on is
aime
d at th
e effic
acy o
f 1D
vs. 2
D mo
delin
g app
roac
hes a
nd ap
plies
to an
y hy
drau
lic m
odeli
ng pa
ckag
e. Th
e NRC
does
not r
ecom
mend
spec
ific m
odeli
ng
softw
are p
acka
ges.
Actio
n:
No ch
ange
to te
xt.
32
[M. M
oens
sens
] Lo
catio
n: P
age
100,
ASC
E (2
005b
) Co
mm
ent:
The r
efere
nce s
hould
be up
dated
to A
SCE/
SEI 7
-10 s
ince t
his is
the
most
up-to
-date
refer
ence
for t
he st
anda
rd.
Resp
onse
: Re
feren
ce up
dated
. Ac
tion:
Re
feren
ce to
ASC
E/SE
I 7-0
5 has
been
repla
ced w
ith
ASCE
/SEI
7-10
.
33
[J. R
iley]
Loca
tion:
Gen
eral
Com
men
t:
The I
SG is
not c
lear o
n how
off-s
ite te
mpor
ary s
tructu
res c
an be
cre
dited
for f
lood p
rotec
tion
Resp
onse
: On
-site
or o
ff-sit
e te
mpo
rary
stru
cture
s can
cont
inue
to b
e cr
edite
d in
the
R2.1
flood
haz
ard
reev
aluat
ion if
such
cred
it has
bee
n ev
aluat
ed a
nd a
ccep
ted
by
NRC
staff p
rior t
o the
50.54
(f) in
forma
tion r
eque
st
P
age
15 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Conc
ern:
Te
mpor
ary o
ff-sit
e stru
cture
s may
alre
ady b
e in p
lace f
or so
me pl
ants.
Pr
opos
ed R
esol
utio
n: N
ot p
rovid
ed
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Not
pro
vided
(USN
RC 20
12).
All o
ther t
empo
rary
struc
tures
, or
meas
ures
(inclu
ding m
itigati
on or
comp
ensa
tory
meas
ures
), sh
ould
not b
e cre
dited
in th
e floo
d ha
zard
reev
aluati
on. T
empo
rary
struc
tures
or
meas
ures
not c
redit
ed in
the h
azar
d ree
valua
tion
may b
e pro
pose
d as i
nterim
actio
ns an
d disc
usse
d in
the ap
prop
riate
secti
on(s)
of th
e haz
ard r
eeva
luatio
n re
spon
se as
desc
ribed
in th
e 50.5
4(f)
infor
matio
n re
ques
t lette
r (US
NRC
2012
).
Actio
n:
The p
rece
ding t
ext h
as be
en ad
ded t
o sec
tion 4
.2.2
34
[J. R
iley]
Loca
tion:
Sec
. 1 / p
. 1
Com
men
t: “F
ailur
es of
wate
r-stor
age o
r wate
r-con
trol s
tructu
res (
such
as on
site
cooli
ng or
auxil
iary w
ater r
eser
voirs
and o
nsite
leve
es) t
hat a
re lo
cated
at
or ab
ove t
he gr
ade o
f safe
ty-re
lated
equip
ment
are p
otenti
al flo
oding
me
chan
isms.”
Co
ncer
n:
List s
hould
spec
ificall
y exc
lude
tank
s. No
te th
at th
e 50
.54(
f) let
ter o
nly a
sks f
or e
xtern
al flo
od e
valua
tions
Pr
opos
ed R
esol
utio
n:
Spec
ificall
y inc
lude “
tanks
” in th
e list
. Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We
need
to d
evelo
p ad
dition
al gu
idanc
e on
the
scop
e of
the
ISG
as w
ell Re
spon
se:
Tank
s are
exclu
ded.
Actio
n:
Tank
exclu
sion a
dded
to S
ectio
n 1.1
(Sco
pe)
P
age
16 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
as th
e flo
oding
reev
aluat
ions i
n ge
nera
l.
35
[J. R
iley]
Loca
tion:
Sec
1.3.1
, p 2
Com
men
t: Ma
ny si
tes ha
ve ow
ner-c
ontro
lled l
evee
s, em
bank
ments
, dam
s, co
oling
po
nds,
etc. a
bove
powe
r bloc
k gra
de th
at ar
e lice
nsed
by th
e NRC
as
Seism
ic Ca
tegor
y I. T
hese
stru
cture
s wer
e eva
luated
as S
eismi
c Ca
tegor
y I in
the l
icens
ing ba
sis / s
afety
analy
sis re
port
and a
ffirme
d as
such
by th
e NRC
in a
safet
y eva
luatio
n rep
ort. T
hese
stru
cture
s are
typ
ically
contr
olled
via o
pera
ting p
roce
dure
s, pr
even
tative
ma
inten
ance
s, an
d sur
veilla
nce t
ests.
How
ever
, the D
am F
ailur
e ISG
do
es no
t disc
uss a
n alte
rnati
ve, s
horte
ned a
sses
smen
t or s
creen
ing
path
spec
ificall
y for
thes
e typ
es of
stru
cture
s, no
r doe
s the
ISG
make
an
y refe
renc
e to t
he te
rm S
eismi
c Cate
gory
I. Do S
eismi
c Cate
gory
I wa
ter re
tentio
n stru
cture
s qua
lify fo
r an a
bbre
viated
scre
ening
proc
ess
that c
redit
s the
ir NRC
appr
oved
desig
n and
oper
ation
? Co
ncer
n:
The
ISG
is no
t clea
r on
how
seism
ic ca
tego
ry 1
stru
cture
s are
to b
e ev
aluat
ed fo
r floo
ding
effe
cts. A
llowi
ng fo
r the
ana
lysis
of th
ese
struc
ture
s dur
ing th
e Fu
kush
ima
50.5
4(f)
lette
r seis
mic
reev
aluat
ions
could
lead
to q
uesti
ons o
n th
e co
mple
tene
ss o
f the
Inte
grat
ed
Asse
ssm
ent w
hich
may
hav
e be
en co
mple
ted
prior
to th
e se
ismic
reev
aluat
ion.
Prop
osed
Res
olut
ion:
Not
pro
vided
Un
ders
tand
ing
of C
urre
nt S
tatu
s: N
ot p
rovid
ed
Resp
onse
: Th
is IS
G is
appli
cable
to es
timati
ng flo
od ha
zard
s du
e to f
ailur
e of b
oth on
site a
nd of
fsite
water
contr
ol str
uctur
es an
d imp
ound
ments
(exc
luding
tank
s). F
or
offsit
e stru
cture
s, hy
drolo
gic, s
eismi
c and
sunn
y-day
fai
lure m
echa
nisms
are w
ithin
the sc
ope o
f the R
2.1
Flood
ing H
azar
d Ree
valua
tion a
nd th
is IS
G. F
or
onsit
e stru
cture
s, on
ly hy
drolo
gic an
d sun
ny-d
ay
mech
anism
s are
in sc
ope.
Seis
mic f
ailur
e of o
nsite
str
uctur
es fa
lls w
ithin
the sc
ope o
f the R
2.1 S
eismi
c Re
evalu
ation
s and
is no
t disc
usse
d in t
his IS
G.
Actio
n:
The p
rece
ding t
ext h
as be
en ad
ded t
o the
ISG
36
Loca
tion:
Sec
. 1.3.
2 / p.
4 Re
spon
se:
P
age
17 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
[J. R
iley]
Com
men
t: 4th
full p
arag
raph
of p.
4, la
st se
ntenc
e: “In
lieu o
f a de
tailed
analy
sis,
one c
an si
mply
assu
me th
at the
dam
fails
unde
r app
ropr
iate l
oadin
g an
d mov
e on t
o esti
matio
n of th
e con
sequ
ence
s.”
Conc
ern:
In
lieu o
f a de
tailed
analy
sis, d
oes t
he lic
ense
e hav
e any
alter
nate
optio
ns to
justi
fy tha
t a da
m (w
hich i
s not
scre
ened
-out
acco
rding
to
Secti
on 3)
will
not fa
il, ra
ther t
han s
imply
assu
ming
dam
failur
e?
Prop
osed
Res
olut
ion:
Ex
plain
what
is me
ant b
y a de
tailed
analy
sis –
analy
ze no
n-fai
lure o
r an
alyze
how
the fa
ilure
wou
ld oc
cur.
Clar
ify if
there
are a
ny al
terna
tive o
ption
s to s
imply
assu
ming
dam
failur
e in l
ieu of
a de
tailed
analy
sis. F
or ex
ample
, if a
feder
al ag
ency
ca
n pro
vide j
ustifi
catio
n tha
t the d
ams t
hey o
wn an
d ope
rate
will n
ot fai
l un
der t
he sc
enar
ios de
scrib
ed in
this
ISG,
clar
ify if
the lic
ense
e can
rely
on th
e ass
ertio
n of a
fede
ral a
genc
y in l
ieu of
a de
tailed
analy
sis.
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
W
e und
ersta
nd th
at the
detai
ls of
shar
ing an
alysis
resu
lts pe
rform
ed by
oth
er fe
dera
l age
ncies
is st
ill be
ing de
velop
ed an
d tha
t the i
ntent
of the
IS
G is
to all
ow us
e of a
nalys
es pr
epar
ed by
othe
r age
ncies
as lo
ng as
the
analy
sis m
eets
the gu
idanc
e in t
he IS
G.
The c
urre
nt sta
ff pos
ition i
s tha
t hyd
rolog
ic fai
lure
and s
eismi
c fail
ure c
an be
ruled
out w
ith ap
prop
riate
justifi
catio
n. F
or da
ms th
at ar
e not
scre
ened
out
acco
rding
to se
ction
3 (i.e
. the d
am is
“pote
ntiall
y cri
tical”
), thi
s will
requ
ire a
detai
led an
alysis
. The
de
tailed
analy
sis ca
n be f
rom
an ex
isting
stud
y pe
rform
ed by
the d
am ow
ner,
A su
nny-d
ay fa
ilure
ca
nnot
be ru
led ou
t, eve
n by d
etaile
d ana
lysis,
sinc
e the
re is
no w
idely
acce
pted m
ethod
ology
for
estim
ating
failu
re pr
obab
ilities
on th
e ord
er of
1e-6
pe
r yea
r. A
detai
led an
alysis
is ge
nera
lly on
e tha
t take
s into
ac
coun
t site
-spec
ific ch
arac
terist
ics of
the w
atersh
ed
and t
he da
m(s)
and d
oes s
o in a
man
ner t
hat
incor
pora
tes m
ore o
f the p
hysic
s tha
n the
scre
ening
ap
proa
ches
.. We d
o not
prov
ide a
prec
ise de
finitio
n for
detai
led an
alysis
. The
comp
onen
ts of
a deta
iled
analy
sis w
ill va
ry on
a ca
se-b
y-cas
e bas
is.
Profe
ssion
al jud
gmen
t is re
quire
d. St
udies
by ot
her f
eder
al ag
encie
s can
be us
ed to
ru
le ou
t hyd
rolog
ic or
seism
ic fai
lure,
but n
ot su
nny-
day f
ailur
e. A
ctio
n:
No pr
opos
ed ch
ange
s to t
ext.
37
[J. R
iley]
Loca
tion:
1.3.
2, p.
4 Co
mm
ent:
Resp
onse
: Th
e scre
ening
meth
ods d
escri
bed i
n Sec
tion 3
are
inten
ded t
o be p
erfor
med u
sing p
ublic
ly av
ailab
le
P
age
18 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
“Dam
failu
re flo
od ha
zard
estim
ation
will
requ
ire co
llecti
ng da
ta on
the
dam
(s) to
be an
alyze
d (e.g
., des
ign do
cume
nts, c
onstr
uctio
n rec
ords
, ma
inten
ance
, and
insp
ectio
n pro
gram
, plan
ned m
odific
ation
s)”
Conc
ern:
W
hat c
an be
done
if re
cord
s can
not b
e loc
ated?
Are
ther
e any
re
ason
able
assu
mptio
ns th
at ca
n be m
ade?
Are
ther
e a m
inimu
m se
t of
reco
rds n
eede
d. No
te tha
t the r
igor o
f justi
ficati
on is
going
to be
depe
nden
t on t
he
avail
abilit
y of in
forma
tion.
Prop
osed
Res
olut
ion:
If d
etaile
d hist
orica
l infor
matio
n can
not b
e obta
ined,
rece
nt (la
st 5
year
s) ins
pecti
on re
ports
and e
valua
tions
by th
e dam
regu
lator
can b
e us
ed to
deter
mine
if the
re ar
e flaw
s or v
ulner
abilit
ies th
at sh
ould
be
evalu
ated f
or da
m fai
lure r
isk.
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Not
pro
vided
infor
matio
n (e.g
. pub
lic N
ID fie
lds).
Deta
iled
analy
ses w
ill ge
nera
lly re
quire
the t
ypes
of
infor
matio
n refe
renc
ed in
the c
omme
nt.
The t
ype a
nd am
ount
of inf
orma
tion r
equir
ed to
su
ppor
t a de
tailed
analy
sis w
ill va
ry on
a ca
se-b
y-ca
se ba
sis. I
n som
e cas
es co
nser
vativ
e as
sump
tions
may
be us
ed in
lieu o
f data
. Pr
ofess
ional
judgm
ent is
need
ed. If
suffic
ient
infor
matio
n to s
uppo
rt de
tailed
analy
sis is
not
avail
able,
failu
re sh
ould
be po
stulat
ed an
d the
co
nseq
uenc
es an
alyze
d. Ac
tion:
No
text
chan
ge.
38
[J. R
iley]
Loca
tion:
1.3.2
, p. 4
Co
mm
ent:
“Tra
nspo
rt of
sedim
ent a
nd de
bris
by flo
od w
aters
shou
ld be
co
nside
red.”
Co
ncer
n:
Not c
lear w
hat th
is sta
temen
t is re
quirin
g and
how
to pe
rform
a se
dimen
t and
debr
is an
alysis
beyo
nd en
ginee
ring j
udgm
ent. W
here
is
sedim
ent a
conc
ern?
Wha
t sca
le/typ
e of d
ebris
is of
conc
ern?
Th
e ISG
leav
es th
is ev
aluati
on up
to th
e lice
nsee
and w
ill pr
obab
ly re
sult i
n lar
ge va
riatio
n. Ad
dition
al gu
idanc
e on h
ow to
deal
with
debr
is
Resp
onse
: An
alysis
meth
ods f
or flo
od-b
orn d
ebris
are d
iscus
sed
in se
ction
4.2.8
. Th
e main
conc
erns
rega
rding
sedim
ent tr
ansp
ort
includ
e: 1)
impa
cts to
pred
icted
wate
r sur
face
eleva
tions
(e.g.
sedim
ent d
epos
ition w
ill re
sult i
n hig
her w
ater le
vels
for a
given
disc
harg
e); 2
) sco
ur at
SS
C str
uctur
es; a
nd 3)
sedim
ent a
ccum
ulatio
n in
UHS
impo
undm
ent.
How
ever
, deta
iled g
uidan
ce on
sedim
ent tr
ansp
ort
mode
ling i
s bey
ond t
he sc
ope t
his IS
G.
P
age
19 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
and s
edim
ent in
the d
am br
eak f
lood w
ave i
s nee
ded.
Prop
osed
Res
olut
ion:
If a
n ana
lysis
is re
quire
d and
expe
cted t
o be p
art o
f the r
epor
t, this
sta
temen
t wou
ld ne
ed to
be ex
pand
ed to
furth
er ch
arac
terize
whe
n se
dimen
t and
debr
is ne
eds t
o be c
onsid
ered
and t
he sp
ecific
conc
erns
tha
t nee
d to b
e add
ress
ed. If
the c
once
rn is
to co
nside
r sou
rces o
f larg
e de
bris
in the
routi
ng pa
th tha
t cou
ld be
tran
spor
ted to
the n
uclea
r site
, it
shou
ld be
state
d as s
uch.
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Not
pro
vided
Actio
n:
Adde
d sec
tion 9
.3 wh
ich di
scus
ses g
ener
al co
nside
ratio
ns fo
r sed
imen
t tran
spor
t mod
eling
and
prov
ides r
efere
nces
to th
e tec
hnica
l liter
ature
.
39
[J. R
iley]
Loca
tion:
Sec
. 1.4.
2, p.
7 Co
mm
ent:
Gene
ral c
omme
nt: T
his se
ction
state
s tha
t the p
roba
bility
targ
et for
jud
ging t
he lik
eliho
od of
a pa
rticula
r fail
ure m
ode/s
cena
rio (e
ither
from
a sin
gle ha
zard
or ap
prop
riate
comb
inatio
n) is
1x10
-6 an
nual
prob
abilit
y. Fr
om th
e abo
ve st
ateme
nt it a
ppea
rs tha
t dam
s whic
h are
safe
for
flood
s with
a pr
obab
ility o
f 10-
6 per
year
need
not to
be ch
ecke
d for
fai
lure d
uring
PMF
. Co
ncer
n:
If it c
an be
demo
nstra
ted th
at a d
am w
ill no
t fail d
uring
a flo
od w
ith
prob
abilit
y of 1
0-6 p
er ye
ar, c
an hy
drolo
gic da
m fai
lure b
e exc
luded
wi
thout
cons
iderin
g PMF
? Pr
opos
ed R
esol
utio
n:
More
clar
ificati
on is
requ
ired t
o clar
ify th
at da
ms no
t failin
g for
10-6
flo
oding
can b
e con
sider
ed as
safe
and p
otenti
al fai
lure d
uring
PMF
do
es no
t nee
d to b
e eva
luated
Resp
onse
: Du
e to t
he la
ck of
wide
ly ac
cepte
d meth
ods f
or
estim
ating
failu
re pr
obab
ilities
on th
e ord
er of
1e-6
pe
r yea
r, thi
s sec
tion h
as be
en re
vised
. The
revis
ed
appr
oach
for p
otenti
ally c
ritica
l/criti
cal d
ams i
s as
follow
s:
1)
PMF
for hy
drolo
gic fa
ilure
2)
1e
-4 ha
zard
curve
for s
eismi
c fail
ure
3)
Assu
me su
nny d
ay fa
ilure
Ac
tion:
Th
is se
ction
has b
een r
evise
d to r
eflec
t the a
ppro
ach
outlin
ed ab
ove.
P
age
20 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
W
e und
ersta
nd th
at the
10-6
crite
ria w
ill be
remo
ved.
40
[J. R
iley]
Loca
tion:
1.4.2
, p. 7
Co
mm
ent:
Last
bulle
t - st
aff po
sition
state
s “…
acce
ptable
to us
e the
1x10
-4 an
nual
frequ
ency
grou
nd m
otion
s, at
spec
tral fr
eque
ncies
impo
rtant
to the
dam,
for
seism
ic ev
aluati
on of
dams
, inste
ad of
1x10
-6, a
s disc
usse
d abo
ve.
Howe
ver,
appr
opria
te en
ginee
ring j
ustifi
catio
n mus
t be p
rovid
ed to
sh
ow th
at the
dam
has s
uffici
ent s
eismi
c mar
gin. O
therw
ise th
e 1x1
0-6
grou
nd m
otion
s sho
uld be
used
.”
Conc
ern:
• I
t is no
t clea
r how
the 1
0-4 a
nd 10
-6 cr
iteria
shou
ld be
used
. If
suffic
ient m
argin
cann
ot be
estab
lishe
d with
the 1
0-4 c
riteria
, how
could
ad
equa
te jus
tifica
tion b
e ach
ieved
with
the 1
0-6 c
riteria
whe
n it is
as
socia
ted w
ith a
large
r ear
thqua
ke?
• Wha
t con
stitut
es su
fficien
t mar
gin if
a 10-
4 seis
mic h
azar
d ana
lysis
is pe
rform
ed ve
rses a
10-6
seism
ic ha
zard
analy
sis?
Prop
osed
Res
olut
ion:
• C
larify
how
the tw
o seis
mic c
riteria
are t
o be u
sed
• Pro
vide g
uidan
ce on
wha
t amo
unt o
f mar
gin is
suffic
ient.
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
W
e und
ersta
nd th
at the
10-6
crite
ria w
ill be
remo
ved.
Resp
onse
: Du
e to t
he la
ck of
wide
ly ac
cepte
d meth
ods f
or
estim
ating
failu
re pr
obab
ilities
on th
e ord
er of
1e-6
pe
r yea
r, thi
s sec
tion h
as be
en re
vised
. The
revis
ed
appr
oach
for p
otenti
ally c
ritica
l/criti
cal d
ams i
s as
follow
s:
1)
PMF
for hy
drolo
gic fa
ilure
2)
1e
-4 ha
zard
curve
for s
eismi
c fail
ure
3)
Assu
me su
nny d
ay fa
ilure
Ac
tion:
Th
is se
ction
has b
een r
evise
d to r
eflec
t the a
ppro
ach
outlin
ed ab
ove.
41
[J. R
iley]
Loca
tion:
Se
c 1.4
.2, p
. 8
Com
men
t: Re
spon
se:
Due t
o the
lack
of w
idely
acce
pted m
ethod
s for
P
age
21 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
2nd b
ullet
on p.
8, ne
xt to
last s
enten
ce: “
Howe
ver,
appr
opria
te en
ginee
ring j
ustifi
catio
n mus
t be p
rovid
ed to
show
that
the da
m ha
s su
fficien
t seis
mic m
argin
.” Co
ncer
n:
No qu
antita
tive c
riteria
for “
suffic
ient m
argin
” are
prov
ided.
Prop
osed
Res
olut
ion:
Th
e 10-
4 ann
ual fr
eque
ncy g
roun
d moti
on is
comp
arab
le to
GMRS
. Fa
ctor o
f safe
ty in
NRC
regu
lator
y guid
ance
for li
quefa
ction
and s
lope
stabil
ity fo
r GMR
S ca
n be u
sed t
o dem
onstr
ate “s
uffici
ent m
argin
.” Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We u
nder
stand
that
the 10
-6 cr
iteria
will
be re
move
d.
estim
ating
failu
re pr
obab
ilities
on th
e ord
er of
1e-6
pe
r yea
r, thi
s sec
tion h
as be
en re
vised
. The
revis
ed
appr
oach
for p
otenti
ally c
ritica
l/criti
cal d
ams i
s as
follow
s:
1)
PMF
for hy
drolo
gic fa
ilure
2)
1e
-4 ha
zard
curve
for s
eismi
c fail
ure
3)
Assu
me su
nny d
ay fa
ilure
Ac
tion:
Th
is se
ction
has b
een r
evise
d to r
eflec
t the a
ppro
ach
outlin
ed ab
ove.
42
[J. R
iley]
Loca
tion:
Sec
. 1.4
.2, p
.8
Com
men
t: 2n
d bull
et on
p. 8,
last
sente
nce:
“Othe
rwise
10-6
grou
nd m
otion
s sh
ould
be us
ed.”
Conc
ern:
Th
e 10-
6 gro
und m
otion
crite
ria ap
pear
s to b
e mor
e con
serva
tive t
han
NRC
ISG-
20, “
PRA
base
d Seis
mic M
argin
s Ana
lysis”
whe
re 1.
67 *
GMRS
is us
ed as
a sc
reen
ing cr
iteria
. Co
mmen
t also
appli
es to
Sec
5.3.1
, p. 4
8, 1s
t par
agra
ph.
Prop
osed
Res
olut
ion:
“O
therw
ise 10
-6 gr
ound
moti
ons s
hould
be us
ed.”
shou
ld be
repla
ced
by “O
therw
ise da
m se
ismic
capa
city g
reate
r tha
n 1.67
*(10-
4 gro
und
Resp
onse
: Th
e 1e-
6 crite
ria ha
s bee
n rem
oved
. How
ever
, the
staff p
ositio
n tha
t ana
lysis
to sh
ow th
at 1e
-6 cr
iteria
is
met is
not s
tate o
f pra
ctice
infor
ms th
e pos
ition t
o re
quire
sunn
y-day
failu
re be
assu
med a
nd
cons
eque
nces
analy
zed.
Due t
o the
lack
of w
idely
acce
pted m
ethod
s for
es
timati
ng fa
ilure
prob
abilit
ies on
the o
rder
of 1e
-6
per y
ear,
this s
ectio
n has
been
revis
ed. T
he re
vised
ap
proa
ch fo
r pote
ntiall
y criti
cal/c
ritica
l dam
s is a
s fol
lows:
1)
PM
F for
hydr
ologic
failu
re
P
age
22 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
motio
ns) s
hould
be de
mons
trated
.” Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We u
nder
stand
that
the 10
-6 cr
iteria
will
be re
move
d.
2)
1e-4
haza
rd cu
rve fo
r seis
mic f
ailur
e 3)
As
sume
sunn
y day
failu
re
Actio
n:
This
secti
on ha
s bee
n rev
ised t
o refl
ect th
e app
roac
h ou
tlined
abov
e.
43
[J. R
iley]
Loca
tion:
Sec
. 1.5.
3, p.
10
Com
men
t: St
aff P
ositio
n, 1s
t bull
et: “I
f a fe
dera
lly ow
ned d
am is
iden
tified
as
critic
al to
the flo
oding
rean
alysis
, the l
icens
ee sh
ould
conta
ct NR
C pr
omptl
y. NR
C wi
ll act
as th
e inte
rface
betw
een t
hese
agen
cies a
nd
licen
sees
. Mem
oran
da of
Agr
eeme
nt or
othe
r mec
hanis
ms ar
e bein
g de
velop
ed to
facil
itate
shar
ing of
data
(inclu
ding n
eces
sary
safeg
uard
s to
prote
ct se
nsitiv
e info
rmati
on) b
etwee
n NRC
and t
he ap
prop
riate
feder
al ag
encie
s.”
Conc
ern:
• I
f infor
matio
n fro
m a f
eder
al ag
ency
is co
nside
red c
lassif
ied, w
ould
this
infor
matio
n be l
imite
d to t
he go
vern
ment
agen
cies o
r wou
ld the
licen
see
be in
volve
d?
Prop
osed
Res
olut
ion:
Fo
llowi
ng th
e dev
elopm
ent o
f the M
emor
anda
of A
gree
ment,
inclu
de in
thi
s ISG
infor
matio
n reg
ardin
g how
to ha
ndle
requ
ests
for in
forma
tion
that m
ay be
cons
idere
d clas
sified
by a
feder
al ag
ency
. Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We
unde
rsta
nd th
at a
Mem
oran
dum
of A
gree
men
t is u
nder
Resp
onse
: St
ill wo
rking
on th
e MOA
. How
ever
, the d
etails
on
the co
ntent
of the
MOA
is no
t the s
ubjec
t of th
is IS
G Ac
tion:
No
chan
ge to
text.
P
age
23 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
deve
lopm
ent t
hat w
ill de
scrib
e ho
w inf
orm
ation
can
be co
mm
unica
ted
and
cont
rolle
d.
45
[J. R
iley]
Loca
tion:
Sec
. 1.5.
3 / p
. 10
Com
men
t: St
aff P
ositio
n, 1s
t bull
et: “I
t is im
porta
nt to
note
that in
man
y cas
es
feder
al ag
encie
s tha
t own
or op
erate
dams
have
a co
nduc
ted de
tailed
fai
lure a
nalys
is. T
o the
exten
t thes
e ana
lyses
are a
pplic
able,
they
sh
ould
be us
ed in
the R
ecom
mend
ation
2.1 f
loodin
g rea
nalys
is.”
Conc
ern:
De
tails
of the
agen
cy’s
exist
ing da
m fai
lure a
nalys
es m
ay no
t be
prov
ided t
o the
licen
see o
r may
be co
nside
red c
lassif
ied. If
the f
ull
detai
ls of
the ag
ency
’s ex
isting
analy
ses a
re no
t ava
ilable
to th
e lic
ense
e, it m
ay no
t be p
ossib
le to
deter
mine
that
the an
alyse
s are
ap
plica
ble an
d mee
t the c
riteria
for t
he R
ecom
mend
ation
2.1 f
loodin
g re
analy
sis.
Prop
osed
Res
olut
ion:
Cl
arify
whe
ther t
he on
us is
on th
e lice
nsee
or th
e fed
eral
agen
cy to
de
termi
ne th
at the
exist
ing da
m fai
lure a
nalys
es pe
rform
ed by
fede
ral
agen
cies a
re ap
plica
ble an
d mee
t the c
riteria
for t
he R
ecom
mend
ation
2.1
flood
ing re
analy
sis, in
the e
vent
that th
e deta
ils of
thes
e ana
lyses
ar
e not
prov
ided t
o the
licen
see.
Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We
unde
rsta
nd th
at a
Mem
oran
dum
of A
gree
men
t is u
nder
de
velop
men
t tha
t will
desc
ribe
how
infor
mat
ion ca
n be
com
mun
icate
d an
d co
ntro
lled
Resp
onse
: St
ill wo
rking
on th
e MOA
, but
the de
tails
of the
MOA
ar
e bey
ond t
he sc
ope o
f this
ISG.
Ac
tion:
No
Cha
nge t
o tex
t.
46
Loca
tion:
Re
spon
se:
P
age
24 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
[J. R
iley]
Sec 1
.5.3,
p. 10
Co
mm
ent:
Staff
Pos
ition,
1st b
ullet:
“In t
he ca
se of
dams
and l
evee
s own
ed or
op
erate
d by U
.S. fe
dera
l age
ncies
, the f
eder
al ag
ency
resp
onsib
le (o
wner
/oper
ator)
for th
e dam
shou
ld be
invo
lved i
n any
disc
ussio
ns,
includ
ing po
ssibl
y rev
iewing
any a
nalys
is pe
rform
ed.”
Conc
ern:
It i
s unc
lear if
this
poss
ible r
eview
is to
occu
r as p
art o
f the e
valua
tion o
r co
ncur
rentl
y with
NRC
revie
w. It
is no
ted th
at the
NRC
-man
dated
sc
hedu
le for
evalu
ation
s may
not p
ermi
t suc
h age
ncies
to pe
rform
a re
view
given
their
othe
r com
mitm
ents
and r
espo
nsibi
lities
. This
sta
temen
t wou
ld ap
pear
to im
ply su
ppor
t for u
sing p
revio
us an
alyse
s of
upstr
eam
struc
tures
that
have
been
revie
wed a
nd ac
cepte
d by t
he
feder
al ow
ner/o
pera
tors o
f suc
h stru
cture
s. FE
RC is
a fed
eral
agen
cy
which
does
not o
wn or
oper
ate da
ms, b
ut dir
ectly
regu
lates
dam
safet
y of
licen
sed h
ydro
powe
r dam
s.
Prop
osed
Res
olut
ion:
Not
pro
vided
Un
ders
tand
ing
of C
urre
nt S
tatu
s: N
ot p
rovid
ed
The a
ction
s disc
usse
d her
e are
envis
ioned
as ta
king
place
durin
g the
evalu
ation
. Us
e of e
xistin
g stud
ies, a
s app
licab
le, is
envis
ioned
. Ac
tion:
No
chan
ge to
text.
47
[J. R
iley]
Loca
tion:
Sec
1.5.3
, p. 1
0 Co
mm
ent:
Staff
Pos
ition,
3rd b
ullet:
“In m
ost c
ases
dams
and l
evee
s will
be ow
ned
and o
pera
ted by
priva
te en
tities
and r
egula
ted by
a sta
te ag
ency
. In th
is ca
se, th
e lice
nsee
shou
ld int
erac
t dire
ctly w
ith th
e own
er an
d reg
ulator
. Th
e lice
nsee
shou
ld no
tify N
RC if
they e
ncou
nter d
ifficu
lties i
n obta
ining
inf
orma
tion.
On a
case
-by-c
ase b
asis,
NRC
may
be ab
le to
prov
ide
some
assis
tance
in in
terfac
ing w
ith st
ate ag
encie
s.”
Resp
onse
: Th
e lice
nsee
shou
ld no
tify N
RC if
they e
ncou
nter
diffic
ulties
in ob
tainin
g info
rmati
on
Actio
n:
No ch
ange
to te
xt.
P
age
25 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Conc
ern:
Ba
sed o
n exp
erien
ce, m
any d
am ow
ners
cons
ider d
am sa
fety-r
elated
inf
orma
tion t
o be h
ighly
sens
itive.
Diss
emina
tion o
f infor
matio
n rela
ted
to da
m fai
lure m
echa
nisms
, dam
stab
ility,
and h
ydra
ulic c
apac
ity is
lik
ely to
be re
strict
ed. F
ERC
has a
spec
ific de
signa
tion,
“CEI
I,” (C
ritica
l En
ergy
Infra
struc
ture I
nform
ation
) tha
t is ap
plied
to “s
ensit
ive”
infor
matio
n, the
reby
, labe
led as
non-
publi
c. Th
e NRC
shou
ld co
nside
r pr
oacti
vely
reac
hing o
ut to
state
dam
safet
y reg
ulator
y age
ncies
to
infor
m the
m of
forthc
oming
infor
matio
n req
uests
from
plan
t own
ers a
nd
to em
phas
ize th
e imp
ortan
ce of
this
infor
matio
n to s
uppo
rt the
se
evalu
ation
s. Th
ere c
an be
hund
reds
or ev
en th
ousa
nds o
f dam
s in t
he
water
shed
upstr
eam
of a n
uclea
r fac
ility;
there
fore,
direc
t inter
actio
n wi
th ea
ch ow
ner w
ould/
could
be co
st an
d tim
e pro
hibitiv
e.
Prop
osed
Res
olut
ion:
Not
pro
vided
Un
ders
tand
ing
of C
urre
nt S
tatu
s: N
ot p
rovid
ed
48
[J. R
iley]
Loca
tion:
Sec
. 2.2.
3, p.
20
Com
men
t: La
st bu
llet in
list: “
Inabil
ity to
war
n in a
dvan
ce…
” Co
ncer
n:
Unlik
e the
othe
r bull
ets in
the l
ist, th
is bu
llet s
eems
mor
e like
a co
nseq
uenc
e of fa
ilure
rathe
r tha
n a ca
usati
ve fa
ilure
mec
hanis
m,
exce
pt po
ssibl
y in t
he ca
se of
a ca
scad
ing fa
ilure
sequ
ence
, whic
h is
discu
ssed
in th
e nex
t sec
tion.
Prop
osed
Res
olut
ion:
Su
gges
t dele
ting b
ullet,
or cl
arify
ing ho
w it m
ight a
pply
as a
failur
e me
chan
ism.
Resp
onse
: Op
erati
onal
failur
es an
d con
trolle
d rele
ases
are o
f co
ncer
n main
ly in
flood
ing sc
enar
ios.
Actio
n:
Disc
ussio
n of o
pera
tiona
l failu
res a
nd co
ntroll
ed
relea
ses m
oved
into
secti
on on
hydr
ologic
failu
res.
P
age
26 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
It is u
nder
stood
that
the fa
ilure
mec
hanis
m is
asso
ciated
with
the f
ailur
e of
upstr
eam
dams
Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We
unde
rsta
nd th
at th
e te
xt wi
ll be
mod
ified
to in
dicat
e th
e co
ncer
n wi
th
upstr
eam
dam
s and
to fo
cus o
n fa
ilure
s tha
t my r
esult
in in
abilit
y to
warn
in a
dvan
ce.
49
[J. R
iley]
Loca
tion:
Sec
3.2,
p. 23
Co
mm
ent:
Why
was
500-
year
flood
data
selec
ted to
be us
ed fo
r ana
lyses
rathe
r tha
n 100
-year
data?
Co
ncer
n:
Prop
osed
Res
olut
ion:
Not
pro
vided
Un
ders
tand
ing
of C
urre
nt S
tatu
s: N
ot p
rovid
ed
Resp
onse
: Th
e 500
-year
flood
was
selec
ted to
cons
erva
tively
ac
coun
t for a
ntece
dent
cond
itions
. Ac
tion:
No
chan
ge te
xt.
50
[J. R
iley]
Loca
tion:
Sec
. 3.2,
p. 2
4 Co
mm
ent:
Item
4: “H
ydro
logic
Mode
l Meth
od (s
ee F
igure
13):
Use a
n ava
ilable
ra
infall
-runo
ff-ro
uting
softw
are p
acka
ge (e
.g. H
EC-H
MS) t
o ass
ess d
am
failur
e sce
nario
s.”
Conc
ern:
Ca
n HEC
-1 be
used
as th
e hyd
rolog
ical m
odel
metho
d?
Prop
osed
Res
olut
ion:
Not
pro
vided
Un
ders
tand
ing
of C
urre
nt S
tatu
s: N
ot p
rovid
ed
Resp
onse
: Ch
oice o
f mod
eling
pack
age i
s up t
o lice
nsee
. The
NR
C do
es no
t end
orse
spec
ific m
odeli
ng so
ftwar
e pa
ckag
es.
Actio
n:
No ch
ange
to te
xt.
51
Loca
tion:
Sec
3.2.1
, p. 2
8 Re
spon
se:
P
age
27 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
[J. R
iley]
Com
men
t: 2n
d par
a. : “
Topo
grap
hic in
forma
tion f
rom
LiDAR
or a
DEM
at the
loc
ation
of th
e hyp
otheti
cal d
am is
used
to de
velop
a sta
ge-st
orag
e fun
ction
for t
he hy
pothe
tical
dam.
This
stag
e stor
age f
uncti
on is
used
to
deter
mine
the w
ater s
urfac
e elev
ation
of th
e hyp
otheti
cal d
am.”
Co
ncer
n:
Grou
ping a
larg
e num
ber o
f dam
s tog
ether
wou
ld re
sult i
n an
unre
alisti
cally
larg
e res
ervo
ir volu
me. A
pplyi
ng ac
tual to
pogr
aphic
inf
orma
tion t
o dev
elop a
stag
e-sto
rage
func
tion f
or su
ch a
rese
rvoir m
ay
resu
lt in v
ery l
arge
wate
r sur
face e
levati
ons a
nd, th
us, v
ery l
arge
hy
drau
lic he
ad. T
he IS
G sh
ould
ackn
owled
ge (s
imila
r to t
he w
ordin
g in
the th
ird pa
ragr
aph)
that
the hy
pothe
tical
dam
shou
ld be
repr
esen
tative
of
the co
llecti
ve da
m he
ights
of the
indiv
idual
struc
tures
it re
pres
ents,
wh
ile si
multa
neou
sly re
pres
entin
g an a
ppro
priat
ely co
nser
vativ
e sc
enar
io thr
ough
the a
pplic
ation
of a
hypo
thetic
al co
llecti
ve st
orag
e vo
lume.
In
addit
ion, s
electi
ng br
each
deve
lopme
nt pa
rame
ters,
such
as br
each
de
velop
ment
time,
requ
ire en
ginee
ring j
udgm
ent in
cons
idera
tion o
f the
fact th
at the
dam
in qu
estio
n is h
ypoth
etica
l and
not a
n actu
al str
uctur
e. Pr
opos
ed R
esol
utio
n: N
ot p
rovid
ed
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Not
pro
vided
The I
SG st
ates i
n the
third
para
grap
h tha
t clus
tering
of
dams
shou
ld ma
ke hy
drolo
gic se
nse.
Th
e poin
t is th
at wa
ter vo
lumes
shou
ld be
co
nser
ved,
not h
eights
of da
ms. I
f the D
EM is
not
used
to de
velop
a sta
ge-st
orag
e cur
ve, th
e stag
e-sto
rage
curve
for t
he hy
pothe
tical
dam
may b
e de
rived
by su
mming
the s
tage-
stora
ge cu
rves o
f the
indivi
dual
dams
. The
heigh
t of th
e hyp
otheti
cal d
am
deve
loped
in th
is ma
nner
will
be eq
ual to
the h
eight
of the
talle
st ac
tual d
am.
Brea
ch m
odels
cons
isten
t with
the s
creen
ing le
vel
analy
sis in
this
secti
on sh
ould
requ
ire on
ly ba
sic
infor
matio
n (he
ight o
f dam
and p
erha
ps re
servo
ir vo
lume)
. Mor
e deta
iled b
reac
h mod
els w
ould
not b
e ap
prop
riate
for th
e scre
ening
analy
sis.
Actio
n:
Para
grap
h add
ed to
desc
ribe a
ltern
ative
appr
oach
: A
s an
alte
rnat
ive
(if a D
EM is
not u
sed t
o dev
elop a
sta
ge-st
orag
e cur
ve),
the st
age-
stora
ge cu
rve fo
r the
hy
pothe
tical
dam
may b
e der
ived b
y sum
ming
the
stage
-stor
age c
urve
s of th
e ind
ividu
al da
ms. T
he
heigh
t of th
e hyp
otheti
cal d
am de
velop
ed in
this
mann
er w
ill be
equa
l to th
e heig
ht of
the ta
llest
actua
l dam
. The
actua
l elev
ation
of da
m wo
uld be
de
rived
from
the D
EM.
P
age
28 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
No ch
ange
to te
xt.
52
[J. R
iley]
Loca
tion:
Sec
4.2
.2.3
, p. 3
4 Co
mm
ent:
Staff
Pos
ition,
2nd b
ullet:
“…at
least
one t
urbin
e sho
uld al
ways
be
assu
med t
o be d
own (
e.g., f
or m
ainten
ance
or ot
her r
easo
ns) in
pe
rform
ing flo
od ro
uting
s.”
Conc
ern:
Da
m op
erato
rs typ
ically
perfo
rm th
eir m
ainten
ance
activ
ities o
utside
of
the flo
od se
ason
. Ass
umpti
on th
at on
e unit
is ou
t of s
ervic
e is
exce
ssive
. • O
verly
cons
erva
tive a
ssum
ption
Pr
opos
ed R
esol
utio
n:
• Ass
ume a
ll unit
s are
usab
le, us
e full
powe
r plan
t disc
harg
e cap
acity
. • I
n lar
ge riv
er sy
stems
with
mult
iple g
ener
ating
dams
does
each
ge
nera
ting d
am ha
ve to
cons
ider o
ne tu
rbine
out o
f ser
vice?
. Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We u
nder
stand
that
the do
cume
nt ma
y be r
evise
d to a
llow
for
justifi
catio
n of tu
rbine
avail
abilit
y in l
arge
river
syste
ms w
ith m
ultipl
e ge
nera
ting d
ams.
Resp
onse
: W
ith re
gard
to cr
editin
g rele
ase c
apac
ity th
roug
h ap
purte
nanc
es ot
her t
han t
he sp
illway
(e.g.
, outl
ets,
turbin
es),
exist
ing fe
dera
l guid
ance
is no
t con
sisten
t. Fo
r exa
mple,
USA
CE en
ginee
ring m
anua
l EM
1110
-2-
1603
, “Hy
drau
lic D
esign
of S
pillw
ays”
states
that
a po
werh
ouse
shou
ld no
t be c
onsid
ered
as a
relia
ble
disch
arge
facil
ity w
hen c
onsid
ering
the s
afe
conv
eyan
ce of
the s
pillw
ay. C
onve
rsely,
FER
C En
ginee
ring G
uideli
nes f
or th
e Eva
luatio
n of
Hydr
opow
er P
rojec
ts sta
tes th
at tho
se re
lease
fac
ilities
whic
h can
be ex
pecte
d to o
pera
te re
liably
un
der t
he as
sume
d floo
d con
dition
can b
e cre
dited
for
flood
routi
ng. U
SBR
best
prac
tice g
uideli
nes
(USB
R 20
11) s
ugge
st tha
t at le
ast o
ne tu
rbine
sh
ould
alway
s be a
ssum
ed to
be do
wn (e
.g. fo
r ma
inten
ance
or ot
her r
easo
ns) in
perfo
rming
flood
ro
uting
. St
aff P
ositi
ons:
•
Relea
se ca
pacit
y thr
ough
appu
rtena
nces
oth
er th
an th
e spil
lway
(e.g.
, outl
ets,
turbin
es) m
ay be
cred
ited a
s par
t of th
e tota
l av
ailab
le re
lease
capa
city,
with
appr
opria
te en
ginee
ring j
ustifi
catio
n tha
t thes
e ap
purte
nanc
es w
ill be
avail
able
and r
emain
op
erati
onal
durin
g a flo
od ev
ent.
Acce
ss to
the
site
durin
g a flo
od ev
ent s
hould
be
P
age
29 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
cons
idere
d.
• Th
e gen
erato
rs an
d tra
nsmi
ssion
facil
ities t
o su
ppor
t the c
redit
ed tu
rbine
(s) m
ust b
e sh
own t
o be o
pera
tiona
l und
er co
ncur
rent
flood
and e
xpec
ted pr
evail
ing w
eathe
r co
nditio
ns if
the tu
rbine
s are
cred
ited a
s par
t of
the to
tal av
ailab
le re
lease
capa
city.
Ac
tion:
IS
G re
vised
to in
clude
the t
ext a
bove
,
53
[J. R
iley]
Loca
tion:
4.2.2
.3, p
. 34
Com
men
t: “T
he po
tentia
l for f
lood-
born
e deb
ris to
redu
ce sp
illway
capa
city s
hould
be
cons
idere
d.”
Conc
ern:
Th
e crite
ria fo
r con
sider
ing po
tentia
l deb
ris bl
ocka
ge at
a sp
illway
are
not c
lear.
If a sp
illway
is ga
ted w
ith 40
-foot
wide
gates
, are
ther
e crite
ria
for ho
w mu
ch bl
ocka
ge sh
ould
be co
nside
red o
r how
the s
pillw
ay
capa
city m
ay be
redu
ced b
y floo
d-bo
rne d
ebris
? • “
This
statem
ent n
eeds
a re
feren
ce.”
Could
not fi
nd th
e sou
rce
Prop
osed
Res
olut
ion:
If d
ebris
bloc
kage
is co
nside
red a
s a po
tentia
l vuln
erab
ility o
f a sp
illway
, cla
rify cr
iteria
rega
rding
spillw
ay ca
pacit
y red
uctio
n. Un
ders
tand
ing
of C
urre
nt S
tatu
s:
Resp
onse
: Th
e disc
ussio
n of s
pillw
ay bl
ocka
ge ha
s bee
n ex
tende
d to p
rovid
e add
itiona
l guid
ance
. Hist
orica
l inf
orma
tion a
nd de
bris
studie
s are
prop
osed
as th
e be
st so
urce
s of in
forma
tion.
Guida
nce f
or sp
illway
ca
pacit
y red
uctio
n is p
rovid
ed fo
r dam
s with
debr
is ma
nage
ment.
Ac
tion:
Mo
re de
tailed
staff
posit
ions o
n spil
lway
bloc
kage
ha
ve be
en ad
ded t
o this
secti
on:
• Th
e po
tentia
l for
flo
od-b
orne
de
bris
to re
duce
sp
illwa y
ca
pacit
y sh
ould
be
cons
idere
d. H
istor
ical in
forma
tion
on d
ebris
pr
oduc
tion
in the
wa
tersh
ed
or
simila
r wa
tersh
eds
shou
ld be
use
d to
asse
ss th
e po
tentia
l deb
ris vo
lumes
. •
For d
ams
that h
ave
debr
is ma
nage
ment,
a
P
age
30 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
We u
nder
stand
that
this a
dditio
nal g
uidan
ce is
being
deve
loped
. se
nsitiv
ity
study
as
sumi
ng
a 5-
10%
re
ducti
on in
cap
acity
sho
uld b
e pe
rform
ed.
Desc
ribe
struc
tures
, eq
uipme
nt an
d pr
oced
ures
us
ed
to pr
even
t sp
illway
blo
ckag
e by w
aterb
orne
debr
is.
• Fo
r da
ms t
hat
lack
debr
is ma
nage
ment
grea
ter
capa
city
redu
ction
s sh
ould
be
cons
idere
d.
The
appr
opria
te ca
pacit
y re
ducti
on w
ill va
ry on
a c
ase-
by-ca
se b
asis.
Ju
stific
ation
for t
he re
ducti
on us
ed sh
ould
be
prov
ided
(e.g.
, de
bris
studie
s for
the
wa
tersh
ed or
simi
lar w
atersh
eds).
54
[J. R
iley]
Loca
tion:
4.2.
6, p
38
Com
men
t: St
aff P
ositio
n: As
writt
en, th
e guid
ance
is am
biguo
us as
to th
e ev
aluati
on(s)
that
shou
ld be
cond
ucted
for g
ate fa
ilure
. Fur
ther,
it doe
s no
t add
ress
gate
failur
e for
mult
iple u
pstre
am da
ms.
Conc
ern:
Th
ere a
re in
finite
perm
utatio
ns fo
r fail
ure o
f gate
s give
n the
infor
matio
n pr
ovide
d. Th
e sec
ond s
taff p
ositio
n is i
ncom
plete
Prop
osed
Res
olut
ion:
Cl
arify
the g
uidan
ce fo
r gate
failu
re.
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
W
e und
ersta
nd th
at thi
s add
itiona
l guid
ance
is be
ing de
velop
ed.
Resp
onse
: Di
fficult
to pr
ovide
detai
led gu
idanc
e on g
ate fa
ilure
du
e to w
ide va
riety
of ga
te typ
es. T
he co
ncer
n her
e is
that r
easo
nable
allow
ance
shou
ld be
mad
e for
po
tentia
l failu
res.
If a ga
te fai
lure c
an be
hand
led
(e.g.
, free
boar
d still
adeq
uate)
, goo
d. If a
ll gate
s av
ailab
le re
quire
d to a
void
over
toppin
g (i.e
., ev
eryth
ing ne
eds t
o wor
k per
fectly
), the
n the
re
shou
ld be
some
conc
ern.
Fuse
plug
s are
gene
rally
cons
idere
d to b
e reli
able,
bu
t ther
e is s
ome i
nher
ent u
ncer
tainty
abou
t the
exac
t dep
th an
d dur
ation
of ov
ertop
ping n
eede
d to
initia
te br
each
. The
re is
also
unce
rtaint
y abo
ut the
ex
act r
ate of
brea
ch de
velop
ment.
Und
ersta
nding
the
mag
nitud
e of th
ese u
ncer
tainti
es is
impo
rtant
beca
use d
elaye
d ope
ratio
n of th
e fus
e plug
to le
ad to
fai
lure o
f the d
am.
P
age
31 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Staff
posit
ion:
• W
ith re
gard
to fu
se pl
ugs,
one s
hould
show
tha
t floo
d rou
tings
are n
ot se
nsitiv
e to t
he
depth
and d
urati
on of
over
toppin
g nee
ded t
o ini
tiate
brea
ch so
that
delay
ed op
erati
on
does
not le
ad to
failu
re of
a ma
in da
m.
Actio
n:
Text
adde
d for
fuse
plug
s
55
[J. R
iley]
Loca
tion:
4.2.7
.1, p
38
Com
men
t: St
aff P
ositio
n: Th
e pote
ntial
for ba
sin to
gene
rate
mud/d
ebris
flows
shou
ld be
co
nside
red.
Conc
ern:
W
hat is
the s
ignific
ance
and c
once
rn w
ith m
ud/de
bris
as it
relat
es to
da
m fai
lure a
nalys
is or
impa
ct to
the re
servo
ir? A
re ba
sin sp
ecific
stu
dies b
eing r
ecom
mend
ed or
requ
ired?
Pr
opos
ed R
esol
utio
n:
The p
urpo
se an
alyzin
g mud
/debr
is ne
eds t
o be d
escri
bed i
nclud
ing th
e ha
zard
/risk a
ssoc
iated
with
mud
flows
. Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We u
nder
stand
that
this s
ectio
n may
be de
leted
or m
odifie
d to a
ddre
ss
debr
is an
d sed
imen
t, not
mud.
Resp
onse
: Mu
d flow
s rem
oved
. Ac
tion:
Se
ction
mod
ified t
o add
ress
debr
is an
d sed
imen
t.
56
Loca
tion:
4.2.
7.2,
p 3
9 Re
spon
se:
P
age
32 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
[J. R
iley]
Com
men
t: St
aff P
ositio
n: Im
pact
loads
on st
ructu
res d
ue to
wate
rbor
ne de
bris
shou
ld be
co
nside
red.
In ge
nera
l, meth
ods o
utline
s in t
he F
EMA
Coas
tal
Cons
tructi
on M
anua
l and
aver
age s
ize/w
eight
for ob
jects
spec
ified i
n AS
CE S
tanda
rds a
re ac
cepta
ble
Conc
ern:
W
hat s
tructu
res n
eed t
o be e
valua
ted fo
r impa
ct loa
ds fo
r the
HRR
ve
rsus t
he IA
? Doe
s this
apply
only
to the
dams
and a
ppur
tenan
ces?
If thi
s ana
lysis
is int
ende
d for
the N
PP si
te, di
scre
te ve
locitie
s will
be
requ
ired a
t eac
h stru
cture
being
evalu
ated.
The d
ebris
sour
ces a
long
with
the si
ze an
d dep
th of
the flo
od w
ill de
termi
ne th
e volu
me
Prop
osed
Res
olut
ion:
Cl
arify
posit
ion on
the c
ondit
ions b
eing u
sed t
o gen
erate
the d
ebris
(P
MF or
dam
failur
e, etc
) and
whe
re im
pact
loads
mus
t be e
valua
ted. If
IA
assu
mes a
ll floo
ded S
SC’s
are l
ost, w
ould
debr
is dy
nami
c loa
d an
alysis
wou
ld no
t be r
equir
ed, o
r is it
only
inten
ded t
o dete
rmine
if flo
od re
tainin
g stru
cture
s sur
vive t
he de
bris
impa
cts?
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
W
e und
ersta
nd th
at the
follo
wing
two s
taff p
ositio
ns w
ill be
adde
d to
addr
ess t
his ite
m:
• Loa
ds du
e to w
aterb
orne
debr
is ca
rried
by flo
od w
aters
shou
ld be
co
nside
red w
ith re
gard
to im
pacts
on th
e dam
(i.e.,
gates
and
asso
ciated
mec
hanic
al eq
uipme
nt, ap
purte
nanc
es, p
arap
ets, e
tc.).
• In t
he ca
se of
dam
brea
k floo
d wav
es, d
ebris
impa
cts to
SSC
s im
porta
nt to
safet
y sho
uld be
cons
idere
d.
Poten
tial fo
r wate
rbor
ne de
bris
impa
cts to
dama
ge
emba
nkme
nt or
key a
ppur
tenan
ces s
hould
be
cons
idere
d. In
the ev
ent th
at the
dam
fails,
wate
r bor
ne de
bris
impa
cts sh
ould
be co
nside
red f
or S
SCs i
mpor
tant to
sa
fety.
Actio
n:
No ch
ange
to te
xt.
P
age
33 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Note
that w
e beli
eve t
hat th
e sec
ond o
f the a
bove
bulle
ts sh
ould
be
chan
ged a
s foll
ows t
o pro
vided
addit
ional
clarifi
catio
n: “…
loads
due t
o de
bris
impa
ct …
shou
ld be
deter
mine
d.”
57
[J. R
iley]
Loca
tion:
Sec
5.2
.1, p
. 46
Com
men
t: 3r
d par
a. : “
This
type o
f cra
cking
even
tually
lead
s to i
solat
ed bl
ocks
wi
thin t
he da
m tha
t sub
sequ
ently
rotat
e and
swing
down
strea
m or
do
wnstr
eam,
relea
sing t
he re
servo
ir.”
Conc
ern:
Pl
ease
rewo
rd th
is se
ntenc
e to c
larify
the i
ntent.
Pr
opos
ed R
esol
utio
n: N
ot p
rovid
ed
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Not
pro
vided
Resp
onse
: Th
e inte
nt is
to de
scrib
e the
conv
entio
nal w
isdom
ab
out h
ow ar
ch da
ms m
ay fa
il in s
eismi
c eve
nt. T
his
infor
matio
n cou
ld be
used
to m
odel
brea
ch, if
ne
eded
. Ac
tion:
No
chan
ge to
text.
58
[J. R
iley]
Loca
tion:
5.2.
4, p
48
Com
men
t: St
aff po
sition
for le
vee f
ailur
e dur
ing a
seism
ic ev
ent -
assu
mptio
n of
startin
g wate
r leve
l is no
t indic
ated
Conc
ern:
Pr
opos
ed R
esol
utio
n:
Star
ting w
ater le
vel s
hould
be co
nsist
ent w
ith th
at as
sume
d for
a se
ismic
dam
failur
e eva
luatio
n Un
ders
tand
ing
of C
urre
nt S
tatu
s: N
ot p
rovid
ed
Resp
onse
: Th
e mod
ified a
ppro
ach t
o seis
mic f
ailur
es st
ates t
hat
the 50
0 yea
r floo
d sho
uld be
used
whe
n the
dam
fails
unde
r ½ of
the 1
e-4 s
eismi
c haz
ard.
So,
when
da
m fai
lure i
s ass
umed
w/o
any s
eismi
c ana
lysis,
the
500-
year
flood
cond
ition s
hould
be us
ed.
Actio
n:
Text
in se
ction
mod
ified t
o add
staff
posit
ion
Staf
f Pos
ition
:
If seis
mic f
ailur
e is s
imply
assu
med w
ithou
t ana
lysis,
the
seism
ic fai
lure s
hould
be as
sume
d to o
ccur
un
der 5
00-ye
ar flo
od co
nditio
ns.
P
age
34 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
59
[J. R
iley]
Loca
tion:
Sec
.5.6,
p. 5
5 Co
mm
ent:
Staff
Pos
ition,
1st b
ullet:
“Dam
failu
re du
e to a
n ear
thqua
ke sh
ould
be
cons
idere
d for
both
maxim
um no
rmal
oper
ating
(“ful
l poo
l”) an
d ave
rage
re
servo
ir lev
els.”
Conc
ern:
• T
he “m
axim
um fu
ll poo
l leve
l” gen
erall
y cor
resp
onds
to a
10%
/year
fre
quen
cy. T
hus,
the jo
int ev
ent fa
ilure
prob
abilit
y con
sider
ing th
e ma
ximum
norm
al op
erati
ng fu
ll poo
l leve
l is co
nser
vativ
e by a
n ord
er of
ma
gnitu
de.
• Hea
d wate
r/tail
wate
r rela
tions
hip pr
escri
bed i
s not
poss
ible f
or
multip
le re
servo
irs be
ing si
mulat
ed in
a co
ntinu
ous h
ydra
ulic m
odel
for
casc
ading
dam
failur
es.
Prop
osed
Res
olut
ion:
• S
ugge
sted c
hang
e: “D
am an
alysis
to sh
ow su
fficien
t mar
gin fo
r 10-
4 gro
und
motio
ns sh
ould
cons
ider m
edian
(or a
vera
ge) r
eser
voir l
evels
. Max
imum
oper
ating
full
pool
level
(10 p
erce
ntile)
shou
ld be
cons
idere
d with
10-3
grou
nd m
otion
s.”
• Rev
ise gu
idanc
e for
the h
ead w
ater/t
ail w
ater r
elatio
nship
as ap
plied
to
casc
ading
dam
failur
es
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Not
pro
vided
Resp
onse
: Us
e max
imum
norm
al po
ol ele
vatio
n (i.e
. top
of
activ
e stor
age p
ool).
Othe
r star
ting w
ater s
urfac
e ele
vatio
ns m
ay be
used
, with
appr
opria
te jus
tifica
tion.
Justi
ficati
on sh
ould
be ba
sed o
n op
erati
ng ru
les an
d ope
ratin
g hist
ory o
f the
re
servo
ir.
Use h
ydro
dyna
mica
lly co
nsist
ent h
eadw
ater/t
ailwa
ter
relat
ions f
or ro
uting
. But
favor
able
head
water
/tailw
ater r
elatio
ns sh
ould
not b
e ass
umed
in
the se
ismic
capa
city a
nalys
is Ac
tion:
St
aff po
sition
s mod
ified t
o clar
ify w
ater s
urfac
e ele
vatio
n and
head
water
/tailw
ater p
ositio
ns.
60
[J. R
iley]
Loca
tion:
Sec
. 5.6
, p. 5
5 Co
mm
ent:
“Give
n the
haza
rd fr
eque
ncy t
arge
t of 1
x10-
6 disc
usse
d in S
ectio
n 1.4
.2, th
e dam
failu
re flo
od w
ave a
t the s
ite sh
ould
be co
mbine
d with
flo
ws of
a fre
quen
cy th
at re
sult i
n a co
mbine
d ann
ual p
roba
bility
of
1x10
-6. F
or ex
ample
, if th
e dam
fails
unde
r a 10
-4 gr
ound
moti
on,
Resp
onse
: Un
derst
andin
g is c
orre
ct. IS
G wi
ll rev
ert to
mod
ified
ANS-
2.8 ap
proa
ch in
whic
h SSE
is re
place
d by 1
e-4
seism
ic ha
zard
and O
BE is
repla
ced b
y half
of th
e 1e
-4 ha
zard
.
P
age
35 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
comb
ine th
e dam
brea
k floo
d wav
e with
a 10
0-ye
ar flo
od. If
the d
am
fails
unde
r a 10
-3 gr
ound
moti
on, c
ombin
e the
dam
brea
k floo
d wav
e it
with
a 100
0-ye
ar flo
od.”
Conc
ern:
• I
n the
exam
ple, th
e com
bined
even
t pro
babil
ity do
es no
t rea
sona
bly
acco
unt fo
r the
fact
that th
e 100
0-ye
ar flo
od is
a se
ason
al ev
ent a
nd th
e ma
ximum
flood
wate
r leve
l at th
e plan
t site
for t
he 10
00-ye
ar riv
er flo
od
is pr
esen
t for a
limite
d par
t of th
e yea
r only
. The
earth
quak
e gro
und
motio
n (an
d the
resu
lting f
lood w
ave)
and t
he 10
00-ye
ar flo
od ar
e ind
epen
dent
even
ts. T
hus,
the jo
int pr
obab
ility o
f occ
urre
nce o
f the
comb
ine ev
ent s
hould
cons
ider t
he lim
ited d
urati
on of
the m
axim
um
flood
leve
l for a
1000
-year
flood
. • T
he co
mbini
ng of
an ea
rthqu
ake a
nd
a floo
d by s
imply
mult
iplyin
g the
ir ann
ual p
roba
bilitie
s of o
ccur
renc
e do
es no
t allo
w for
the v
ery s
mall d
urati
on w
ithin
a yea
r for
the
earth
quak
e to c
oincid
e with
a lon
ger b
ut sti
ll only
a fai
rly sm
all fr
actio
n of
a yea
r for
the d
urati
on of
mos
t floo
ds.
• This
para
grap
h is c
hang
ed fr
om pr
eviou
sly ex
pres
sed N
RC po
sition
s as
disc
uss i
n pub
lic m
eetin
gs
• Wha
t com
binati
on sh
ould
be ap
plied
if se
ismic
failur
e is j
ust a
ssum
ed?
Prop
osed
Res
olut
ion:
• S
ugge
sted c
hang
e: “F
or ex
ample
, if th
e dam
fails
unde
r a 10
-4 gr
ound
mo
tion,
comb
ine th
e dam
brea
k floo
d wav
e with
a 10
-year
flood
. If th
e da
m fai
ls un
der a
10-3
grou
nd m
otion
, com
bine t
he da
m br
eak f
lood
wave
with
a 10
0-ye
ar flo
od. T
his ex
ample
assu
mes t
hat th
e high
flood
lev
el at
the pl
ant s
ite fo
r the
10-ye
ar an
d 100
-year
flood
s will
last
appr
oxim
ately
1-mo
nth (1
0% of
one y
ear)
or le
ss be
fore r
eced
ing.”
• See
meth
odolo
gy in
: Eve
nt Co
mbina
tion A
nalys
is for
Des
ign an
d Re
habil
itatio
n of U
.S. A
rmy C
orps
of E
ngine
ers N
aviga
tion S
tructu
res
Actio
n:
Text
modif
ied to
follo
w the
mod
ified A
NS-2
.8 ap
proa
ch.
P
age
36 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
by B
ruce
R. E
llingw
ood,
Contr
act R
epor
t ITL-
95-2
, July
1995
, US
Army
Co
rps o
f Eng
ineer
s, W
aterw
ays E
xper
imen
t Stat
ion
• Use
even
t com
binati
ons a
s pre
vious
ly de
scrib
ed in
publi
c mee
tings
: 1.
seism
ic ha
zard
freq
uenc
y tar
get o
f 1x1
0-4 w
ith 25
year
flood
, 2. 0
.5 x
seism
ic ha
zard
freq
uenc
y tar
get o
f 1x1
0-4 w
ith 50
0 yea
r floo
d. Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We u
nder
stand
that
the A
NS 2.
8 seis
mic a
nd flo
oding
even
t co
mbina
tions
(mod
ified w
ith 10
-4 gr
ound
moti
on) w
ill be
used
in th
e fin
al ve
rsion
of th
e ISG
. i.e.,
• 1
0-4 g
roun
d moti
on w
ith 25
year
flood
(Alt 1
), • ½
of 10
-4 gr
ound
moti
on w
ith ½
-PMF
or 50
0 yea
r floo
d, wh
ichev
er is
les
s (Al
t 2)
60
[J. R
iley]
Loca
tion:
Sec
. 6.1.
3 / p
. 67
Com
men
t: Ge
nera
l com
ment:
It is
uncle
ar w
hethe
r the
sunn
y day
failu
re
mech
anism
is ap
plica
ble to
leve
es, s
ince l
evee
s are
norm
ally s
ubjec
t to
water
load
ing on
ly du
ring f
loodin
g eve
nts.
Conc
ern:
It i
s rec
ogniz
ed th
at lev
ee fa
ilure
shou
ld be
assu
med i
f the l
evee
is
over
toppe
d. Le
vee f
ailur
e at e
levati
ons l
ess t
han o
verto
pping
shou
ld be
inv
estig
ated;
howe
ver,
it is d
ebata
ble w
hethe
r the
se co
nditio
ns ca
n be
cons
idere
d “su
nny d
ay.”
Prop
osed
Res
olut
ion:
Su
gges
t con
sider
ation
be gi
ven t
o rem
oving
leve
es fr
om th
e sun
ny da
y fai
lure m
echa
nism
secti
on, a
nd ad
ding t
he in
forma
tion a
bout
levee
Resp
onse
: Su
nny-d
ay fa
ilure
of le
vee i
s not
very
likely
to re
sult
in flo
oding
. Ac
tion:
Su
nny-d
ay fa
ilure
of le
vees
remo
ved f
rom
ISG
P
age
37 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
failur
es in
clude
d her
e to t
he hy
drolo
gic fa
ilure
mec
hanis
m, w
ith
addit
ional
infor
matio
n as n
eede
d.
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Th
e guid
ance
on le
vees
was
mov
ed fr
om th
is se
ction
but th
e hea
ding
for th
e 6.1.
3 still
need
s to b
e dele
ted.
61
[J. R
iley]
Loca
tion:
6.2,
p 6
8 Co
mm
ent:
“Sun
ny da
y fail
ure m
ay be
exclu
ded f
rom
furthe
r con
sider
ation
if it c
an
be sh
own b
y the
licen
see t
hat th
e pro
babil
ity of
failu
re is
10-6
per y
ear
or le
ss. T
he 10
-6 va
lue is
chos
en si
nce t
here
is no
t suff
icien
t data
to
allow
for a
ccur
ate ca
lculat
ions o
f this
even
t. Rea
sona
ble ar
gume
nts
justify
ing th
e cas
e for
a low
er fa
ilure
prob
abilit
y inc
lude b
ut ar
e not
limite
d to a
recu
rring
dam
inspe
ction
and m
onito
ring p
rogr
am, e
xper
t as
sess
ments
that
the da
m is
in go
od co
nditio
n, an
d deta
iled i
nspe
ction
re
ports
.” Co
ncer
n:
Wha
t meth
odolo
gy fo
r esti
matin
g a pr
obab
ility o
f failu
re is
10-6
per y
ear
or le
ss w
ould
be ac
cepta
ble to
the N
RC fo
r sun
ny-d
ay fa
ilure
inclu
ding
piping
or in
terna
l ero
sion f
ailur
es.
Prop
osed
Res
olut
ion:
Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We u
nder
stand
that
a pro
babil
istic
appr
oach
to su
nny d
ay da
m fai
lure
exclu
sion w
ill no
t be i
nclud
ed in
the d
ocum
ent. S
unny
day f
ailur
es w
ill ne
ed to
be co
nside
red f
or al
l criti
cal d
ams a
ssum
ing th
e dam
s with
stand
hy
drolo
gic ev
ent
Resp
onse
: Cu
rrent
staff p
ositio
n is t
hat s
unny
-day
failu
res o
f cri
tical
dams
shou
ld be
postu
lated
and
cons
eque
nces
analy
zed.
Actio
n:
ISG
modif
ied to
remo
ve pr
obab
ilistic
analy
sis fo
r su
nny-d
ay fa
ilure
s.
P
age
38 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
62
[J. R
iley]
Loca
tion:
Sec
. 6.2.
1 / p
. 68
Com
men
t: St
aff P
ositio
n bull
et: “R
easo
nable
argu
ments
justi
fying
the c
ase f
or a
lower
failu
re pr
obab
ility i
nclud
e but
are n
ot lim
ited t
o…”
Conc
ern:
It i
s unc
lear w
hat “
lower
failu
re pr
obab
ility”
mean
s in t
his co
ntext.
Doe
s it m
ean l
ower
than
10-6
failu
re pr
obab
ility?
Pr
opos
ed R
esol
utio
n:
Addit
ional
desc
riptio
n of h
ow to
apply
prob
abilit
y to t
he su
nny d
ay
failur
e mec
hanis
m an
d pos
sible
pathw
ays t
o tak
e cre
dit fo
r non
-failu
re
would
be he
lpful.
Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We u
nder
stand
that
a pro
babil
istic
appr
oach
to su
nny d
ay da
m fai
lure
exclu
sion w
ill no
t be i
nclud
ed in
the d
ocum
ent.
Resp
onse
: Cu
rrent
staff p
ositio
n is t
hat s
unny
-day
failu
res o
f cri
tical
dams
shou
ld be
postu
lated
and
cons
eque
nces
analy
zed.
Actio
n:
ISG
modif
ied to
remo
ve pr
obab
ilistic
analy
sis fo
r su
nny-d
ay fa
ilure
s.
63
[J. R
iley]
Loca
tion:
Sec
. 6.2
.1 /
p. 6
8 Co
mm
ent:
The S
taff P
ositio
n stat
es th
at re
ason
able
argu
ments
for a
lowe
r tha
n 10-
6 per
year
risk o
f sun
ny da
y fail
ure c
an be
mad
e usin
g the
exist
ence
of
recu
rring
dam
inspe
ction
, mon
itorin
g pro
gram
, exp
ert a
sses
smen
ts tha
t the
dam
is in
good
cond
ition a
nd de
tailed
insp
ectio
n rep
orts.
Co
ncer
n:
Fede
ral a
genc
y dam
owne
rs ge
nera
lly ha
ve al
l of th
is inf
orma
tion a
t ha
nd. U
tilitie
s wou
ld ha
ve to
requ
est th
is da
ta fro
m the
Fed
eral
agen
cy
dam
owne
rs.
Resp
onse
: Cu
rrent
staff p
ositio
n is t
hat s
unny
-day
failu
res o
f cri
tical
dams
shou
ld be
postu
lated
and
cons
eque
nces
analy
zed.
Actio
n:
ISG
modif
ied to
remo
ve pr
obab
ilistic
analy
sis fo
r su
nny-d
ay fa
ilure
s.
P
age
39 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Prop
osed
Res
olut
ion:
Pr
opos
e tha
t the N
RC as
k the
fede
ral a
genc
y dam
owne
rs to
agre
e via
an M
OU to
prov
ide th
is da
ta to
certif
y tha
t their
dams
need
not b
e an
alyze
d in d
etail f
or a
sunn
y day
failu
re.
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Not
pro
vided
W
e und
ersta
nd th
at a p
roba
bilist
ic ap
proa
ch to
sunn
y day
dam
failur
e ex
clusio
n will
not b
e inc
luded
in th
e doc
umen
t
64
[J. R
iley]
Loca
tion:
Sec
6.2.2
/ p. 6
8 Co
mm
ent:
The S
taff P
ositio
n to u
se th
e max
imum
obse
rved o
r max
imum
norm
al po
ol ele
vatio
n for
the s
unny
day b
reac
h ana
lysis
is ex
cess
ive.
Conc
ern:
• “
the m
axim
um ob
serve
d poo
l elev
ation
” may
be a
very
extre
me ev
ent
and n
ot re
flect
sunn
y day
cond
itions
, whic
h if c
onsid
ered
in co
njunc
tion
with
runo
ff fro
m a P
MP co
uld re
sult i
n an u
nrea
sona
ble pr
edict
ed
maxim
um po
ol ele
vatio
n. Su
ch an
extre
me hi
storic
al ev
ent m
ay ha
ve a
very
low fr
eque
ncy a
nd sh
ort d
urati
on re
lative
to hi
storic
al op
erati
on
depe
nding
on th
e rive
rine s
ystem
and t
he up
strea
m wa
tersh
ed.
• The
impli
catio
n of th
e ter
m “su
nny d
ay” is
that
it occ
urs d
uring
non-
flood
cond
itions
. Use
of th
e max
imum
obse
rved p
ool li
nks i
t to th
e infl
ow
of re
cord
for t
he da
m.
Prop
osed
Res
olut
ion:
• T
he de
fault s
tartin
g wate
r sur
face e
levati
on us
ed in
flood
routi
ngs f
or
evalu
ation
of ov
ertop
ping o
r sun
ny da
y fail
ure i
s the
max
imum
norm
al po
ol ele
vatio
n. Ot
her s
tartin
g wate
r sur
face e
levati
ons m
ay be
used
with
Resp
onse
: In
view
of the
unce
rtaint
ies in
volve
d in e
stima
ting
rese
rvoir l
evels
that
migh
t rea
sona
bly be
expe
cted t
o pr
evail
at th
e tim
e of fa
ilure
, the d
efault
star
ting w
ater
surfa
ce el
evati
on us
ed in
flood
routi
ngs f
or
evalu
ation
of ov
ertop
ping s
hould
be th
e max
imum
no
rmal
pool
eleva
tion (
i.e. to
p of a
ctive
stor
age p
ool).
Ot
her s
tartin
g wate
r sur
face e
levati
ons m
ay be
used
, wi
th ap
prop
riate
justifi
catio
n. Ju
stific
ation
shou
ld be
ba
sed o
n ope
ratin
g rule
s and
oper
ating
histo
ry of
the
rese
rvoir.
The
oper
ating
histo
ry us
ed sh
ould
be of
su
fficien
t leng
th to
supp
ort a
ny co
nclus
ions d
rawn
(e
.g., 2
0 yea
rs or
mor
e). B
ut co
nside
ratio
n sho
uld be
giv
en to
poss
ible i
nstan
ces w
here
the o
pera
ting
histor
y and
/or ru
les ha
ve be
en in
fluen
ced b
y an
omalo
us co
nditio
ns su
ch as
drou
ght.
Actio
n:
Prec
eding
text
used
as st
aff po
sition
.
P
age
40 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
appr
opria
te jus
tifica
tion.
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
W
e und
ersta
nd th
at the
text
will b
e mod
ified t
o rea
d: “…
the de
fault i
nitial
wate
r leve
l use
d in b
reac
h ana
lysis
and f
lood
routi
ngs f
or ev
aluati
on of
sunn
y-day
failu
re sh
ould
be th
e high
er of
the
maxim
um ob
serve
d poo
l elev
ation
or th
e max
imum
norm
al po
ol ele
vatio
n. Ot
her w
ater le
vels
may b
e use
d with
justi
ficati
on (e
.g.,
reco
rds s
howi
ng th
at wa
ter le
vels
abov
e max
norm
al po
ll are
infre
quen
t an
d of s
hort
dura
tion)
.” No
te tha
t it w
ould
be us
eful to
desc
ribe t
he at
tribute
s of a
justi
ficati
on of
“in
frequ
ent”
and “
shor
t dur
ation
”.
65
[J. R
iley]
Loca
tion:
Sec
8.1,
p. 72
Co
mm
ent:
2nd p
arag
raph
: “Ho
weve
r, by
using
a da
m-br
each
flood
pred
iction
mo
del a
nd m
aking
seve
ral a
pplic
ation
s of th
e mod
el wh
erein
the b
reac
h wi
dth pa
rame
ter re
pres
entin
g the
comb
ined l
ength
s of a
ssum
ed fa
iled
mono
liths i
s var
ied in
each
appli
catio
n, the
resu
lting r
eser
voir w
ater
surfa
ce el
evati
ons c
an be
used
to in
dicate
the e
xtent
of re
ducti
on of
the
loadin
g pre
ssur
es on
the d
am. S
ince t
he lo
ading
dimi
nishe
s as t
he
brea
ch w
idth i
ncre
ases
, a lim
iting s
afe lo
ading
cond
ition w
hich w
ould
not c
ause
furth
er fa
ilure
may
be es
timate
d.”
Conc
ern:
Th
e ben
efit o
f this
proc
ess i
s unc
lear.
The m
axim
um lo
ading
cond
ition
durin
g an o
verto
pping
even
t wou
ld be
pres
ent a
t time
zero
for a
ll mo
nolith
s. Si
nce f
ailur
e of a
sing
le mo
nolith
is as
sume
d to b
e quit
e sh
ort (
on th
e ord
er of
minu
tes),
redu
ction
s in u
pstre
am w
ater le
vels
are
likely
to no
t be s
ignific
ant e
noug
h to r
educ
e pre
ssur
es on
othe
r
Resp
onse
: Th
e loa
ding c
ondit
ions o
n the
rema
ining
mon
oliths
aft
er on
e has
faile
d will
be si
gnific
antly
diffe
rent
than
befor
e fail
ure (
e.g. th
e mon
oliths
on ei
ther s
ide of
the
failed
secti
on w
ill be
subje
ct to
hydr
odyn
amic
force
s of
the w
ater f
lowing
thro
ugh t
he br
each
). T
he
stabil
ity of
the d
am un
der t
he m
odifie
d loa
ding
cond
ition i
s poin
t to co
nside
r.
Actio
n:
No ch
ange
to te
xt.
P
age
41 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
mono
liths.
Sens
itivity
analy
ses i
ncor
pora
ting p
eak d
owns
tream
brea
ch
flows
and w
ater s
urfac
e elev
ation
s sho
uld al
so be
cons
idere
d as
appr
opria
te ap
proa
ches
to es
timati
ng br
each
widt
h. Pr
opos
ed R
esol
utio
n: N
ot p
rovid
ed
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Not
pro
vided
66
[J. R
iley]
Loca
tion:
Sec
8.2.2
, p 76
Co
mm
ent:
“How
ever
, their
pape
r doe
s not
prov
ide cl
ear c
riteria
for s
electi
ng th
e er
odibi
lity in
dex.”
Co
ncer
n:
Xu an
d Zha
ng (2
009)
do no
t pro
vide d
etaile
d crite
ria fo
r sele
cting
the
erod
ibility
inde
x bec
ause
they
state
that
they u
sed d
efinit
ions i
n a pa
per
by B
riaud
, whic
h pro
vides
detai
led de
finitio
ns.
Prop
osed
Res
olut
ion:
Not
pro
vided
Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We u
nder
stand
that
the X
u and
Zha
ng (2
009)
brea
ch m
ethod
ology
alo
ne is
not r
ecom
mend
ed fo
r the
2.1 h
azar
d re-
analy
sis an
d if u
sed,
would
have
to be
benc
h-ma
rked a
gains
t ano
ther a
ppro
ach.
Resp
onse
: Xu
& Z
hang
state
that
their e
rodib
ility i
ndex
is ba
sed
on th
e clas
sifica
tions
pres
ented
in th
e Bria
ud pa
per.
Howe
ver,
Briau
d stat
es in
his p
aper
that
the
class
ificati
on sy
stem
is me
ant a
s a pr
elimi
nary
desig
n too
l and
that
the er
ror in
his c
atego
ry as
signm
ents
could
as m
uch a
s plus
or m
inus o
ne
class
ificati
on le
vel.
In ad
dition
, Bria
ud do
es no
t pr
ovide
infor
matio
n reg
ardin
g the
numb
er of
soil
tests
that p
rovid
e the
basis
for t
he cl
assif
icatio
n sy
stem.
It ap
pear
s tha
t the c
lassif
icatio
n is b
ased
on
samp
les te
sted i
n his
EFA
devic
e at T
AMU
(e.g
resu
lts fr
om a
single
devic
e/lab
orato
ry). R
egar
dless
of
the le
vel o
f exp
erim
ental
supp
ort fo
r the
Bria
ud
class
ificati
on sy
stem,
Xu &
Zha
ng al
so st
ate th
at the
ir ero
dibilit
y ind
ex ta
kes i
nto ac
coun
t add
itiona
l fac
tors s
uch a
s dam
cros
s-sec
tiona
l geo
metry
, slop
e su
rface
prote
ction
, and
comp
actio
n meth
od.
Howe
ver,
their p
aper
does
not p
rovid
e any
of th
is ad
dition
al inf
orma
tion f
or th
e dam
s exa
mine
d in t
he
study
or pr
ovide
insig
ht int
o how
thes
e add
itiona
l fac
tors w
ere u
sed t
o dete
rmine
their
erod
ibility
inde
x.
Thus
, ther
e is a
lack
of ob
jectiv
e crite
ria fo
r ass
igning
the
Xu &
Zha
ng er
odibi
lity in
dex t
o new
dams
.
P
age
42 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Actio
n:
No ch
ange
to te
xt.
67
[J. R
iley]
Loca
tion:
Sec
8.2
.2, p
76
Com
men
t: “In
addit
ion, a
necd
otal e
viden
ce su
gges
ts tha
t their
relat
ion fo
r fail
ure
time m
ay be
bias
ed in
favo
r of lo
nger
times
(Wah
l, 201
3).”
Conc
ern:
Xu
and Z
hang
defin
e fail
ure t
ime d
iffere
ntly t
han i
n othe
r emp
irical
brea
ch pa
rame
ter st
udies
. This
mea
ns th
at on
e mus
t use
their
failu
re
time e
stima
tes in
a br
each
mod
el (e
.g. H
EC-R
AS) in
a wa
y tha
t is
cons
isten
t with
their
defin
ition.
It is n
ot a f
unda
menta
l defi
cienc
y or f
law
in the
meth
od.
• The
diffe
renc
e in r
epor
ted fa
ilure
time i
s mor
e app
ropr
iately
ch
arac
terize
d as a
diffe
renc
e in h
ow it
is de
fined
base
d on t
he st
artin
g an
d end
ing po
int. N
ot su
re th
at an
ecdo
tal ev
idenc
e is a
ppro
priat
e for
an
ISG
docu
ment
Pr
opos
ed R
esol
utio
n:
Remo
ve th
e stat
emen
t Un
ders
tand
ing
of C
urre
nt S
tatu
s:
We u
nder
stand
that
the X
u and
Zha
ng (2
009)
brea
ch m
ethod
ology
alo
ne is
not r
ecom
mend
ed fo
r the
2.1 h
azar
d re-
analy
sis an
d if u
sed,
would
have
to be
benc
h-ma
rked a
gains
t ano
ther a
ppro
ach.
Resp
onse
: De
finitio
n of fa
ilure
time i
n Xu &
Zha
ng pa
per is
the
wide
ly us
ed de
finitio
n. Bu
t Teto
n Dam
exam
ple gi
ven
in pa
per in
dicate
s tha
t auth
ors d
id no
t con
sisten
tly
apply
the d
efinit
ion. D
efinit
ion of
failu
re tim
e mus
t be
inter
nally
cons
isten
t with
in the
regr
essio
n ana
lysis
and b
etwee
n the
regr
essio
n ana
lysis
and t
he
hydr
ologic
/hydr
aulic
mod
el.
Actio
n:
Addit
ional
text a
dded
to ex
plain
issue
s with
Xu &
Zh
ang p
aper
1)
Inc
onsis
tent u
se of
failu
re tim
e defi
nition
2)
La
ck of
basis
for e
rodil
bility
. Bria
ud’s
work
focus
is on
mea
sure
ment.
Ina
ppro
priat
e for
use w
/ HEC
-RAS
68
Loca
tion:
Sec
8.2.2
.1, p
77
Resp
onse
:
P
age
43 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
[J. R
iley]
Com
men
t: Un
certa
inty i
n Pre
dicted
Bre
ach P
aram
eters
and H
ydro
grap
hs
Conc
ern:
It s
hould
be no
t nec
essa
ry to
cove
r the
extre
me va
lues i
f ther
e is a
so
und b
asis
for lim
iting t
he ra
nge
Prop
osed
Res
olut
ion:
It i
s use
ful to
reco
gnize
that
“unc
ertai
nty” in
regr
essio
n equ
ation
s is
asso
ciated
with
“une
xplai
ned v
arian
ce” a
nd th
at ph
ysica
l ar
gume
nts/en
ginee
ring j
ustifi
catio
ns ca
n be m
ade a
s to w
here
in th
e ra
nge o
f “un
certa
inty”
a par
ticula
r dam
wou
ld be
expe
cted t
o fit g
iven i
ts ph
ysica
l cha
racte
ristic
s tha
t are
not s
pecif
ically
inclu
ded i
n the
“e
xplai
ned v
arian
ce” r
epre
sente
d by t
he m
athem
atica
l form
of th
e re
gres
sion e
quati
on. T
here
fore i
t may
not b
e app
ropr
iate t
o per
form
sens
itivity
analy
ses o
ver t
he en
tire ra
nge o
f unc
ertai
nty on
pred
icted
br
each
para
meter
s (or
pred
icted
peak
brea
ch flo
w ra
tes).
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Not
pro
vided
Evalu
ating
the a
pplic
abilit
y of th
e pro
pose
d re
solut
ion w
ould
requ
ire in
-dep
th ex
amina
tion o
f the
case
stud
ies th
at we
re us
ed to
deve
lop th
e re
gres
sion e
quati
on, in
orde
r to c
ompa
re th
ese d
ams
(or s
ome s
ubse
t of th
em) t
o the
dam
being
mod
eled.
Th
is do
es no
t app
ear t
o be a
trac
table
appr
oach
in
most
case
s. Ac
tion:
No
chan
ge to
text.
69
[J. R
iley]
Loca
tion:
Sec
10.2,
p. 84
Co
mm
ent:
2nd c
omple
te se
ntenc
e : “A
ccur
ate es
timate
s of fl
ood e
levati
on in
area
s of
chan
ging t
opog
raph
y and
near
larg
e obje
cts in
the f
low fie
ld wi
ll typ
ically
requ
ire tw
o-dim
ensio
nal a
nalys
is.”
Conc
ern:
Su
gges
t add
ing “lo
caliz
ed” t
o sen
tence
, as i
t is ty
picall
y not
nece
ssar
y to
perfo
rm tw
o-dim
ensio
nal a
nalys
is of
the en
tire in
unda
tion a
rea,
which
ma
y be h
undr
eds o
f mile
s lon
g: “…
.will
typica
lly re
quire
loca
lized
two-
Resp
onse
: Co
mmen
t acc
epted
Ac
tion:
Te
xt mo
dified
to cl
arify
that
2D an
alysis
need
ed on
ly in
regio
ns w
here
2D ef
fects
are i
mpor
tant.
P
age
44 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
dimen
siona
l ana
lysis.
” Pr
opos
ed R
esol
utio
n: N
ot p
rovid
ed
Unde
rsta
ndin
g of
Cur
rent
Sta
tus:
Not
pro
vided
70
[J.W
. She
a, T
VA]
Loca
tion:
1.3.
2/pa
ge 5
Co
mm
ent:
St
ep 5
-The
read
er is
told
to es
timate
the i
mpac
ts of
sedim
ent a
nd
debr
is tra
nspo
rt.
Conc
ern:
Th
e eva
luatio
n of d
ebris
and s
edim
ent tr
ansp
ort a
nd im
pacts
to flu
id dy
nami
cs re
quire
s exte
nsive
, com
plex a
nalys
is.
Prop
osed
Res
olut
ion:
Cl
arify
whe
ther "
impa
cts" r
efers
to:(1
) im
pacts
on eq
uipme
nt for
use
durin
g the
integ
rated
asse
ssme
nt; or
(2) im
pacts
on th
e flu
id flo
w be
havio
r itse
lf (ch
ange
s in f
luid d
ynam
ics fr
om ad
dition
al se
dimen
t and
de
bris
in the
flood
routi
ng).
Resp
onse
: W
ith re
spec
t to de
bris,
impa
ct loa
ds du
e to
water
born
e deb
ris ar
e the
key i
ssue
. Impa
ct loa
ds on
the
dam
and k
ey ap
purte
nanc
es sh
ould
be
evalu
ated.
In th
e eve
nt of
dam
failur
e, im
pact
loads
du
e to w
aterb
orne
debr
is sh
ould
be co
nside
red f
or
expo
sed S
SCs i
mpor
tant to
safet
y at th
e NPP
site.
Th
e main
conc
erns
rega
rding
sedim
ent tr
ansp
ort
includ
e: 1)
impa
cts to
pred
icted
wate
r sur
face
eleva
tions
(e.g.
sedim
ent d
epos
ition w
ill re
sult i
n hig
her w
ater le
vels
for a
given
disc
harg
e); 2
) sco
ur at
SS
C str
uctur
es; a
nd 3)
sedim
ent a
ccum
ulatio
n in
UHS
impo
undm
ent.
How
ever
, deta
iled g
uidan
ce on
sedim
ent tr
ansp
ort
mode
ling i
s bey
ond t
he sc
ope t
his IS
G.
With
resp
ect to
equip
ment
for us
e in t
he in
tegra
ted
asse
ssme
nt, im
pact
loads
and s
edim
ent tr
ansp
ort
would
be in
clude
d in t
he “a
ssoc
iated
effec
ts” of
flo
oding
that
shou
ld be
inclu
ded i
n the
haza
rd
reev
aluati
on. T
he im
pact
that th
ese a
ssoc
iated
eff
ects
have
on th
e effe
ctive
ness
of eq
uipme
nt an
d/or p
roce
dure
s reli
ed up
on fo
r mitig
ation
wou
ld be
evalu
ated i
n the
integ
rated
asse
ssme
nt, if
one i
s
P
age
45 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
requ
ired.
Ac
tion:
Ad
ded s
ectio
n 9.3
which
disc
usse
s gen
eral
cons
idera
tions
for s
edim
ent tr
ansp
ort m
odeli
ng an
d pr
ovide
s refe
renc
es to
the t
echn
ical li
teratu
re.
71
[J.W
. She
a, T
VA]
Loca
tion:
1.4.
2/pa
ge 8
Co
mm
ent:
Last
bulle
t -Re
quire
s seis
mic a
nalys
is of
1 x 10
-4 w
ith su
fficien
t mar
gin
or se
ismic
analy
sis to
I x 10
-6
Conc
ern:
Th
e ter
m 'su
fficien
t mar
gin" i
s not
defin
ed. A
s use
d, the
term
'suff
icien
t m
argin
" see
ms to
imply
mor
e tha
n mee
ting r
equir
ed fa
ctor o
f safe
ty.
Prop
osed
Res
olut
ion:
De
fine "
suffic
ient m
argin
" to b
e the
requ
ired f
actor
of sa
fety p
er F
eder
al Da
m Sa
fety R
egula
tor's
guida
nce.
This
term
occu
rs in
seve
ral p
laces
thr
ough
out th
e doc
umen
t.
Resp
onse
: Th
is se
ction
mod
ified t
o rem
ove r
equir
emen
t to
evalu
ate se
ismic
haza
rds a
t the 1
e-6 a
nnua
l ex
ceed
ance
leve
l. Ac
tion:
Se
ction
1.4.2
mod
ified t
o refl
ect th
e foll
owing
ap
proa
ches
for h
azar
d eva
luatio
n. 1)
PM
F for
hydr
ologic
failu
re
2)
1e-4
haza
rd cu
rve fo
r seis
mic f
ailur
e 3)
As
sume
sunn
y day
failu
re
72
[J.W
. She
a, T
VA]
Loca
tion:
3.1/
page
22
Com
men
t: St
aff po
sition
says
'dam
s own
ed by
licen
sees
may
not b
e rem
oved
"
Conc
ern:
Th
ere a
re lic
ense
e-ow
ned d
ams t
hat h
ave m
inima
l or n
o adv
erse
failu
re
cons
eque
nces
beyo
nd th
e own
er's
prop
erty.
For
exam
ple, th
ere a
re
holdi
ng po
nds t
hat a
re on
the N
ation
al Inv
entor
y of D
ams t
hat a
re
Resp
onse
: Re
mova
l of d
ams b
ased
only
upon
dama
ge be
ing
limite
d to t
he ow
ner’s
prop
erty
does
not a
pply
to lic
ense
e own
ed da
ms (o
r ons
ite w
ater c
ontro
l str
uctur
es).
In thi
s situ
ation
addit
ional
analy
sis w
ould
be ne
eded
to ju
stify
that th
e dam
or w
ater c
ontro
l str
uctur
e mee
ts the
inten
t of th
e “inc
onse
quen
tial”
categ
ory a
nd m
ay be
remo
ved f
rom
furthe
r
P
age
46 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
owne
d by T
VA. T
hese
are l
ow ha
zard
dams
whe
re fa
ilure
unde
r nor
mal
(non
-flood
) con
dition
s wou
ld re
sult i
n env
ironm
ental
perm
it com
plian
ce
issue
s with
the s
tate a
nd is
ther
efore
deem
ed as
a fai
lure c
onse
quen
ce
to the
owne
r's pr
oper
ty. F
or flo
od an
alysis
, thes
e hold
ing po
nds w
ould
not in
creas
e the
flood
elev
ation
s at th
e site
s and
are i
ncon
sequ
entia
l.
Prop
osed
Res
olut
ion:
Gi
ven t
he si
tuatio
n des
cribe
d in t
he co
ncer
n fiel
d and
the f
act th
at thi
s do
cume
nt is
guida
nce,
the pr
opos
ed ch
ange
to th
e stat
emen
t is th
at the
"lic
ense
e own
ed da
ms sh
ould
not b
e rem
oved
from
cons
idera
tion
witho
ut jus
tifica
tion."
cons
idera
tion.
Actio
n:
Secti
on 3.
1 mod
ified t
o now
read
: Re
mova
l of d
ams b
ased
only
upon
dama
ge be
ing
limite
d to t
he ow
ner’s
prop
erty
does
not a
pply
to lic
ense
e own
ed da
ms (o
r ons
ite w
ater c
ontro
l str
uctur
es).
In thi
s situ
ation
addit
ional
analy
sis w
ould
be ne
eded
to ju
stify
that th
e dam
or w
ater c
ontro
l str
uctur
e mee
ts the
inten
t of th
e “inc
onse
quen
tial”
categ
ory a
nd m
ay be
remo
ved f
rom
furthe
r co
nside
ratio
n.
73
[J.W
. She
a, T
VA]
Loca
tion:
4.1.3
/page
31
Com
men
t: Th
e staf
f pos
ition r
equir
es en
ginee
ring j
ustifi
catio
n if fa
ilure
of sp
illway
ga
tes an
d outl
et wo
rks is
not c
onsid
ered
for h
ydro
logic
failur
e mod
es.
Conc
ern:
W
ith a
comp
lex riv
er sy
stem
with
multip
le da
ms an
d man
y hyd
ro un
its
(IVA
has 1
09 hy
dro u
nits),
the s
taff p
ositio
n is v
ery d
ifficu
lt to i
mplem
ent
witho
ut ex
tensiv
e ana
lysis,
such
as an
exten
sive u
ncer
tainty
analy
sis
with
Monte
Car
lo sim
ulatio
ns or
othe
r suc
h ana
lyses
. The
sche
dule
for
the flo
od ha
zard
reev
aluati
on do
esn't
supp
ort th
is typ
e of a
nalys
is.
Prop
osed
Res
olut
ion:
Re
comm
end a
dding
to th
e staf
f pos
ition,
a thir
d opti
on, w
hich w
ould
be
a sim
plifie
d sys
tem ap
proa
ch th
at all
ows p
roba
bility
of fa
ilure
of ga
tes
and g
ener
ating
units
to op
erate
durin
g floo
d eve
nts or
appli
catio
n of a
n av
ailab
ility f
actor
base
d on h
istor
ical fl
oods
.
Resp
onse
: Th
e staf
f pos
ition i
s only
mea
nt to
conv
ey th
e ge
nera
l requ
ireme
nt for
cons
idera
tion o
f red
uced
co
nvey
ance
capa
city d
ue to
such
failu
res.
More
de
tails
are p
rovid
ed in
subs
eque
nt se
ction
s of th
e IS
G.
Actio
n:
The p
resu
mptio
n of fa
ilure
has b
een r
emov
ed fr
om
the st
aff po
sition
.
P
age
47 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
74
[J.W
. She
a, T
VA]
Loca
tion:
4.2/p
age 3
2, 5.2
/page
45, &
6.1.1
/page
66
Com
men
t: Th
e guid
ance
is no
t clea
r on t
he es
tablis
hmen
t of lo
ads/d
eman
ds fo
r de
tailed
analy
sis.
Conc
ern:
Th
ere i
s no s
epar
ate se
ction
in th
e guid
ance
for e
stabli
shing
the
dema
nds/l
oads
for t
he de
tailed
analy
sis as
outlin
ed in
the f
lowch
art in
Fig
ure 2
of S
ectio
n 1.3.
The
dema
nds/l
oads
are a
ddre
ssed
in th
e ov
ertop
ping s
ectio
n of th
e doc
umen
t but
only
brief
ly. It
is no
t clea
r to t
he
read
er if
these
load
s are
to in
clude
the c
ombin
ed ef
fects
from
Appe
ndix
H of
NURE
G/CR
-704
6, e.g
., Alte
rnati
ve 1
comb
inatio
n of m
ean m
onthl
y ba
se flo
w, m
edian
soil m
oistur
e, an
antec
eden
t or s
ubse
quen
t rain
that
is the
less
er of
40%
PMP
or 50
0 yea
r rain
fall, t
he P
MP an
d wav
es
induc
ed by
2-ye
arwi
nd sp
eed a
pplie
d alon
g the
critic
al dir
ectio
n.
Prop
osed
Res
olut
ion:
Pr
ovide
clea
r guid
ance
on th
e esta
blish
ment
of the
dema
nds/l
oads
wh
ich ar
e to b
e use
d for
the d
etaile
d ana
lysis
of the
dams
. This
same
co
mmen
t also
appli
es to
seism
ic loa
d/dem
ands
for d
etaile
d ana
lysis
and f
or su
nny d
ay lo
ads/d
eman
ds fo
r deta
iled a
nalys
is. G
uidan
ce
shou
ld inc
lude s
uch
spec
ifics a
s the
follo
wing
: (1)
head
water
and
tailw
ater le
vels
to be
used
in st
abilit
y ana
lysis;
(2)
whe
ther a
ntece
dent
or su
bseq
uent
rainf
all m
ust b
e com
bined
with
PMP
; (3)
whe
ther o
r not
to inc
lude 2
-year
wind
spee
ds in
the
analy
sis; a
nd (4
) ade
quate
facto
rs of
safet
y.
Resp
onse
:
1)
For h
ydro
logic
failur
e ana
lysis,
the d
am
shou
ld be
able
to pa
ss th
e PMF
via t
he
spillw
ay an
d othe
r disc
harg
e outl
ets. T
he
struc
tural
loads
/dema
nds a
re hy
dros
tatic
and h
ydro
dyna
mic l
oads
of th
e res
ervo
ir lev
el as
socia
ted w
ith th
e PMF
as w
ell as
as
socia
ted ef
fects
such
as w
ind w
aves
and
debr
is loa
ds.
Head
water
/tailw
ater le
vels
will b
e gov
erne
d by
inflo
w an
d the
spillw
ay co
nvey
ance
re
lation
ships
(and
poss
ibly b
ackw
ater
effec
ts). H
eadw
ater/t
ailwa
ter el
evati
ons w
ill be
calcu
lated
by th
e hyd
rolog
ic or
hydr
aulic
ro
uting
mod
el us
ed.
The c
ombin
ation
refer
red t
o in t
he co
mmen
t is
one a
ltern
ative
for d
erivi
ng th
e PMF
. PMF
es
timate
s typ
ically
inclu
de as
sump
tions
re
gard
ing an
teced
ent b
ase f
low, s
oil
moist
ure a
nd ra
infall
cond
itions
. Fa
ctors
of sa
fety u
sed i
n stab
ility a
nalys
is sh
ould
be co
nsist
ent w
ith ac
cepte
d en
ginee
ring p
racti
ce an
d stan
dard
s for
the
struc
ture(
s) in
ques
tion.
2)
For s
eismi
c fail
ure,
the lo
ad/de
mand
are
P
age
48 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
those
effec
ts (vi
brato
ry gr
ound
moti
on,
displa
ceme
nt, liq
uefac
tion)
asso
ciated
with
eit
her t
he 1e
-4 se
ismic
haza
rd (o
r half
of th
e 1e
-4 ha
zard
) Fo
r the
seism
ic sta
bility
calcu
lation
, defa
ult
head
water
elev
ation
shou
ld be
max
norm
al po
ol lev
el. O
ther le
vels
can b
e use
d with
jus
tifica
tion.
Tailw
ater s
hould
be av
erag
e, no
nfloo
d lev
els. F
loodin
g con
dition
s sho
uld
not b
e ass
umed
to in
creas
e the
stab
ility o
f the
dam.
Fa
ctors
of sa
fety u
sed i
n stab
ility a
nalys
is sh
ould
be co
nsist
ent w
ith ac
cepte
d en
ginee
ring p
racti
ce an
d stan
dard
s for
the
struc
ture(
s) in
ques
tion.
If the
dam
fails,
the d
am br
eak f
lood w
ave
shou
ld be
comb
ined w
ith th
e 25 o
r 500
year
flo
od (d
epen
ding u
pon w
hethe
r dam
faile
d un
der t
he 1e
-4 se
ismic
haza
rd or
½ of
the
1e04
seism
ic ha
zard
). W
hen r
outin
g the
flo
od w
ave,
hydr
ologic
ally c
onsis
tent
head
water
/tailw
ater r
elatio
nship
s, as
ca
lculat
ed by
the h
ydro
logic
or hy
drau
lic
routi
ng m
odel,
shou
ld be
used
.
3)
For s
unny
-day
failu
re, th
e fail
ure i
s sim
ply
assu
med t
o occ
ur. T
here
is no
spec
ific lo
ad
P
age
49 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
or de
mand
. How
ever
, a br
each
scen
ario
must
be po
stulat
ed.
For s
unny
-day
failu
re flo
od ro
uting
, the
defau
lt hea
dwate
r elev
ation
shou
ld be
max
no
rmal
pool
level.
Othe
r leve
ls ca
n be u
sed
with
justifi
catio
n. T
ailwa
ter el
evati
ons w
ill be
ca
lculat
ed by
the h
ydro
logic
or hy
drau
lic
routi
ng m
odel
used
.
Actio
n:
TBD
75
[J.W
. She
a, T
VA]
Loca
tion:
4.2.2
1pag
e 33
Co
mm
ent:
In ma
ny ca
ses t
he ID
F is
the pr
obab
le ma
ximum
flood
(PMF
) dev
elope
d by
analy
zing t
he im
pacts
of th
e pro
bable
max
imum
prec
ipitat
ion (P
MP)
even
t ove
r the
dams
upstr
eam
water
shed
. Co
ncer
n:
The g
uidan
ce se
ems t
o imp
ly tha
t the d
ams b
e eva
luated
for p
rojec
t sp
ecific
PMF
s and
if the
y are
not a
ble to
pass
the p
rojec
t spe
cific
PMFs
the
n the
y sho
uld be
cons
idere
d to f
ail w
ithou
t con
sider
ation
for o
ther
even
ts. W
ith a
comp
lex riv
er sy
stem
with
multip
le da
ms, th
e staf
f po
sition
is un
reali
stic a
nd ov
erly
cons
erva
tive.
The n
uclea
r pow
er pl
ant
PMP
which
prod
uces
the P
MF is
over
a lar
ge w
atersh
ed w
ith sm
aller
am
ounts
of ra
infall
comp
ared
to th
e pro
ject s
pecif
ic PM
Fs w
hich h
ave
very
high a
moun
ts of
PMP
over
a sm
aller
wate
rshed
.
Resp
onse
: NU
REG-
0800
state
s tha
t dam
failu
re sh
ould
be
evalu
ated u
sing a
ppro
pria
te c
ombi
natio
n of
an
tece
dent
flow
s as
des
crib
ed b
y A
NS
I/AN
S-
2.8-
1992
. ANS
-2.8-
1992
state
s tha
t eac
h pote
ntiall
y cri
tical
dam
shou
ld be
subje
cted a
nalyt
ically
to th
e PM
F fro
m the
ir own
contr
ibutin
g wate
rshed
. ANS
-2.8
-199
2 fur
ther s
tates
that
if an u
pstre
am da
m wo
uld lik
ely fa
il in t
he pr
obab
le ma
ximum
flood
from
its
own w
atersh
ed, it
shall
also
be te
sted i
n the
pr
obab
le ma
ximum
flood
appli
cable
to th
e tota
l plan
t sit
e wate
rshed
. If ju
dged
likely
to fa
il in e
ither
case
, the
resu
lting f
lood w
ave s
hall b
e car
ried d
owns
tream
to
the pl
ant s
ite fo
r com
paris
on an
d sele
ction
of th
e cri
tical
case
.
P
age
50 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Prop
osed
Res
olut
ion:
In
addit
ion to
the e
valua
tion o
f the d
ams f
or th
e IDF
, allo
w the
larg
e wa
tersh
ed P
MP an
d ass
ociat
ed P
MF to
be us
ed to
evalu
ate th
e stab
ility
of the
dams
whe
n the
re is
a lar
ge w
atersh
ed w
ith m
any u
pstre
am da
ms.
This
would
be a
furthe
r refi
neme
nt in
the hi
erar
chica
l haz
ard a
nalys
is (H
HA) p
roce
ss.
Actio
n:
No ch
ange
to te
xt
76
[J.W
. She
a, T
VA]
Loca
tion:
4.2.2
.2/pa
ge 34
Co
mm
ent:
Staff
posit
ion ta
lks ab
out "
maxim
um no
rmal
pool
eleva
tion"
Co
ncer
n:
Maxim
um no
rmal
pool
eleva
tion t
erm
is no
t defi
ned.
Prop
osed
Res
olut
ion:
De
fine w
hat °
maxim
um no
rmal"
is, a
nd/or
prov
ide ex
ample
s for
diffe
rent
kinds
of re
servo
irs. T
VA de
fines
max
imum
norm
al as
the n
orma
l su
mmer
pool.
Maxim
um no
rmal
pool
eleva
tion i
s defi
ned a
s the
ele
vatio
n cor
resp
ondin
g to t
he to
p of th
e acti
ve
stora
ge.
Actio
n:
Adde
d a fig
ure t
o Sec
tion 2
.1.3 t
o clar
ify w
ater le
vels
and s
torag
e volu
me de
finitio
ns. D
efinit
ions a
re al
so
prov
ided i
n the
Ter
ms an
d Defi
nition
s sec
tion (
unde
r sto
rage
)
77
[J.W
. She
a, T
VA]
Loca
tion:
4.2.2
.4/pa
ge 35
Co
mm
ent:
Cons
idera
tion o
f deb
ris bl
ocka
ge of
spillw
ay ga
tes.
Conc
ern:
W
ith a
comp
lex riv
er sy
stem
with
multip
le da
ms an
d man
y hyd
ro un
its
(TVA
has 1
09 hy
dro u
nits),
the s
taff p
ositio
n is v
ery d
ifficu
lt to
imple
ment
witho
ut ex
tensiv
e ana
lysis.
The
sche
dule
for th
e floo
d haz
ard
reev
aluati
on do
esn't
supp
ort th
is lev
el of
analy
sis.
Resp
onse
: 5-
10%
capa
city r
educ
tion i
s rea
sona
ble fo
r dam
s wi
th de
bris
mana
geme
nt. F
or da
ms th
at lac
k deb
ris
mana
geme
nt, gr
eater
redu
ction
s may
be
appr
opria
te. C
apac
ity re
ducti
ons a
s lar
ge as
35%
ha
ve be
en ob
serve
d. T
his de
termi
natio
n nee
ds to
be
mad
e on a
case
-by-c
ase b
asis.
Ac
tion:
Mo
dified
text
to inc
lude d
escri
ption
of La
ke Ly
nn
Dam
debr
is blo
ckag
e. M
odifie
d staf
f pos
ition t
o
P
age
51 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Prop
osed
Res
olut
ion:
Re
comm
end g
uidan
ce pr
ovide
perce
ntage
for s
pillw
ay ga
te blo
ckag
e. TV
A's p
ositio
n tha
t per
forma
nce o
f sen
sitivi
ty an
alyse
s on 5
perce
nt an
d 10
perce
nt sp
illway
gate
block
age i
s app
ropr
iate.
includ
e sen
sitive
ly stu
dy us
ing 5-
10%
capa
city
redu
ction
for d
ams w
ith de
bris
mana
geme
nt. D
ams
witho
ut de
bris
mana
geme
nt sh
ould
cons
ider g
reate
r re
ducti
ons o
n a ca
se-b
y-cas
e bas
is.
78
[J.W
. She
a, T
VA]
Loca
tion:
4.2.2
.4/pa
ge 35
Co
mm
ent:
Last
bulle
t -At
leas
t one
turb
ine sh
ould
alway
s be a
ssum
ed to
be do
wn
in pe
rform
ing flo
od ro
uting
s. Co
ncer
n:
Dam
oper
ators
typica
lly pe
rform
their
main
tenan
ce ac
tivitie
s outs
ide of
the
flood
seas
on an
d the
assu
mptio
n tha
t one
unit i
s out
of se
rvice
for
ever
y hyd
ro da
m in
a lar
ge sy
stem
may b
e ove
rly co
nser
vativ
e. TV
A ha
s com
pleted
the h
azar
d ree
valua
tion i
nput
work
for th
e dar
ns (t
he
dam
ratin
g cur
ves)
assu
ming
that
all th
e hyd
ro un
its ar
e ava
ilable
until
the tu
rbine
deck
, swi
tchya
rd or
powe
rhou
se is
flood
ed.
Prop
osed
Res
olut
ion:
Re
comm
end g
uidan
ce al
low a
simpli
fied s
ystem
appr
oach
that
cons
iders
prob
abilit
y of tu
rbine
outag
es or
appli
catio
n of a
n ava
ilabil
ity
factor
base
d on m
ainten
ance
data
and/o
r hist
orica
l floo
ds.
Resp
onse
: Re
view
of fed
eral
guida
nce o
n cre
diting
disc
harg
e ca
pacit
y thr
ough
show
s tha
t diffe
rent
agen
cies t
ake
differ
ent a
ppro
ache
s. T
here
fore,
turbin
e flow
s can
be
cred
ited,
if eng
ineer
ing ju
stific
ation
is pr
ovide
d.
Actio
n:
Last
bulle
t rem
oved
. Di
scus
sion o
f var
ious f
eder
al gu
idelin
es on
cred
iting
turbin
e/pow
erho
use f
lows i
s add
ed.
Disc
ussio
n on u
se of
site-
spec
ific an
d gen
eric
infor
matio
n on g
ener
ating
unit a
vaila
bility
has b
een
adde
d.
79
[J.W
. She
a, T
VA]
Loca
tion:
4.2.6
/pag
e 39
Com
men
t: St
aff po
sition
–“W
ith re
gard
to th
e fus
e plug
s, on
e sho
uld co
nside
r sh
ow th
at ro
uting
” Co
ncer
n:
Resp
onse
: Te
xt sh
ould
have
read
: Fu
se p
lugs
are
gen
eral
ly c
onsi
dere
d to
be
relia
ble,
bu
t the
re is
som
e in
here
nt u
ncer
tain
ty a
bout
the
exac
t dep
th a
nd d
urat
ion
of o
verto
ppin
g ne
eded
to
initi
ate
brea
ch.
Ther
e is
als
o un
certa
inty
abo
ut th
e
P
age
52 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
The s
enten
ce is
inco
mplet
e and
TVA
is un
able
to un
derst
and t
he st
aff
posit
ion re
gard
ing fu
se pl
ugs.
Pr
opos
ed R
esol
utio
n:
Comp
lete t
he se
ntenc
e.
exac
t rat
e of
bre
ach
deve
lopm
ent.
Und
erst
andi
ng
the
mag
nitu
de o
f the
se u
ncer
tain
ties
is im
porta
nt
beca
use
dela
yed
oper
atio
n of
the
fuse
plu
g to
lead
to
failu
re o
f the
dam
.
Staff
posit
ion sh
ould
have
been
: •
With
reg
ard
to f
use
plug
s, o
ne s
houl
d sh
ow
that
flo
od
rout
ings
ar
e no
t se
nsiti
ve t
o th
e de
pth
and
dura
tion
of
over
topp
ing
need
ed t
o in
itiat
e br
each
so th
at d
elay
ed o
pera
tion
does
not
lead
to
failu
re o
f a m
ain
dam
.
Actio
n:
Text
corre
cted.
80
[J.W
. She
a, T
VA]
Loca
tion:
4.2.7
.2/pa
ge 39
Co
mm
ent:
No eq
uatio
n pro
vided
. Co
ncer
n:
Edito
rial; n
o equ
ation
and v
ariab
les pr
ovide
d.
Prop
osed
Res
olut
ion:
Pr
ovide
equa
tion a
nd de
fine v
ariab
les.
Resp
onse
: Ty
pogr
aphic
erro
r. Ac
tion:
Eq
uatio
n and
defin
ition o
f var
iables
prov
ided.
81
[J.W
. She
a, T
VA]
Loca
tion:
5/pa
ge 43
Co
mm
ent:
Last
para
grap
h, las
t sen
tence
calls
out a
Sec
tion 0
.
Resp
onse
: Re
feren
ce sh
ould
be to
Sec
tion 5
.6
P
age
53 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Conc
ern:
Ed
itoria
l; use
r is no
t able
to de
termi
ne w
hich s
ectio
n was
mea
nt to
be
refer
ence
d.
Prop
osed
Res
olut
ion:
Pr
ovide
the c
orre
ct se
ction
refer
ence
.
Actio
n:
Cros
s refe
renc
e pro
vided
.
82
[J.W
. She
a, T
VA]
Loca
tion:
5.1/p
age 4
3 Co
mm
ent:
Whe
n usin
g the
HHA
proc
ess a
nd as
sumi
ng a
seism
ic da
rn fa
ilure
wi
thout
a deta
iled a
nalys
is of
the da
m, th
ere i
s no f
lood s
pecif
ied to
use
for hy
drolo
gic ro
uting
with
the a
ssum
ed fa
ilure
. Co
ncer
n:
By no
t spe
cifyin
g to t
he us
er, th
e doc
umen
t see
ms to
imply
that
a de
tailed
seism
ic an
alysis
is re
quire
d to b
e per
forme
d whic
h is c
ontra
ry to
NURE
GICR
-704
6 HHA
. Pr
opos
ed R
esol
utio
n:
Prov
ide th
e floo
d whic
h is t
o be u
sed f
or hy
drolo
gic ro
uting
whe
n the
re
is an
assu
med f
ailur
e of th
e dam
unde
r seis
mic l
oadin
g.
Resp
onse
: Th
e mod
ified a
ppro
ach t
o seis
mic s
tates
that
the 50
0 ye
ar flo
od sh
ould
be us
ed w
hen t
he da
m fai
ls un
der
½ of
the 1e
-4 se
ismic
haza
rd. S
o, wh
en da
m fai
lure
is as
sume
d w/o
any s
eismi
c ana
lysis,
the 5
00-ye
ar
flood
cond
ition s
hould
be us
ed.
Actio
n:
Text
in se
ction
mod
ified t
o add
staff
posit
ion
Staf
f Pos
ition
:
• If
seism
ic fai
lure
is sim
ply a
ssum
ed w
ithou
t an
al ysis
, the
se
ismic
failur
e sh
ould
be
assu
med
to oc
cur
unde
r 50
0-ye
ar f
lood
cond
itions
.
83
[J.W
. She
a, T
VA]
Loca
tion:
5.2.3
/page
48
Com
men
t: Se
ismic
analy
sis of
appu
rtena
nt str
uctur
es.
Conc
ern:
Th
is se
ction
impli
es th
e spil
lway
gate
syste
m sh
ould
be se
ismica
lly
Resp
onse
: It i
s com
mon p
racti
ce to
perfo
rm se
ismic
analy
sis of
sp
illway
gates
and o
ther k
ey ap
purte
nanc
es,
beca
use t
heir f
ailur
e can
lead
dire
ctly t
o ove
rtopp
ing
and f
ailur
e of th
e dam
. Ho
weve
r, the
HHA
appr
oach
inclu
des t
he us
e of
P
age
54 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
analy
zed.
It is n
ot co
mmon
prac
tice t
o per
form
detai
led se
ismic
analy
sis
of da
m ap
purte
nanc
es w
ithin
the da
m sa
fety i
ndus
try. T
his is
an
exten
sive a
moun
t of w
ork f
or th
e amo
unt o
f dam
s with
in TV
A's
water
shed
and v
ery d
ifficu
lt for
equip
ment
instal
led 60
-year
s ago
. The
do
cume
ntatio
n of m
ateria
l and
insta
llatio
n deta
ils w
ill be
a ch
allen
ge.
The s
ched
ule fo
r the
flood
haza
rd re
evalu
ation
does
n't su
ppor
t this
type
of an
alysis
. Pr
opos
ed R
esol
utio
n:
Reco
mmen
d staf
f guid
ance
prov
ide an
optio
n to c
onsid
er so
me
cons
erva
tive p
erce
ntage
of fa
ilure
of sp
illway
gates
, outl
et wo
rks an
d oth
er ap
purte
nanc
es in
stead
of co
mpre
hens
ive de
tailed
analy
sis.
cons
erva
tive a
ssum
ption
s in l
ieu of
mor
e deta
iled
analy
sis. I
t wou
ld be
the r
espo
nsibi
lity of
the
licen
see t
o jus
tify th
at so
me pe
rcenta
ge of
failu
re is
co
nser
vativ
e. Ac
tion:
No
chan
ge to
text.
84
[J.W
. She
a, T
VA]
Loca
tion:
5.3.3/
page
51
Com
men
t: De
tailed
inve
stiga
tions
wou
ld inc
lude s
urve
ys an
d und
istur
bed s
ampli
ng
borin
gs.
Conc
ern:
Th
is se
ction
impli
es th
e use
of un
distur
bed s
ampli
ng fo
r dire
ct me
asur
emen
ts of
in sit
u den
sities
and d
ynam
ic pr
oper
ties.
Howe
ver in
sit
u tes
ting i
s ofte
n pre
ferre
d for
perfo
rming
lique
factio
n ana
lysis.
Un
distur
bed s
ampli
ng fo
r labo
rator
y tes
ting o
f pote
ntiall
y liqu
efiab
le so
il oft
en re
sults
in m
ixed r
esult
s.
Prop
osed
Res
olut
ion:
Re
comm
end p
arag
raph
be re
vised
to re
ad: "
Detai
led in
vesti
gatio
ns
would
inclu
de su
rveys
and i
n situ
field
testin
g to (
1) re
fine t
he
preli
mina
ry int
erpr
etatio
n of th
e stra
tigra
phy a
nd th
e exte
nt of
poten
tially
liq
uefia
ble so
ils, a
nd (2
) mea
sure
in si
tu de
nsitie
s and
dyna
mic
prop
ertie
s for
inpu
t to dy
nami
c res
pons
e ana
lyses
. Rec
over
undis
turbe
d
Resp
onse
: Pr
opos
ed re
vised
text
is the
same
as th
e exis
ting
text in
the d
ocum
ent.
Actio
n:
No ch
ange
to te
xt.
P
age
55 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
samp
les fo
r labo
rator
y tes
ting w
hen s
ite so
ils ar
e not
adeq
uatel
y re
pres
ented
in th
e ava
ilable
data
base
.”
85
[J.W
. She
a, T
VA]
Loca
tion:
5.3.3
/page
51
Com
men
t: Se
ction
5.3.3
and S
taff P
ositio
n refe
renc
es N
RC R
egula
tory G
uide
1.198
‘Pro
cedu
res a
nd C
riteria
for A
sses
sing S
eismi
c Soil
Liqu
efacti
on
at Nu
clear
Pow
er P
lants"
as pr
ovidi
ng gu
idanc
e and
detai
led
proc
edur
es fo
r eva
luatin
g liqu
efacti
on.
Conc
ern:
Th
e staf
f pos
ition r
efere
nce t
o RG
1.198
could
imply
that
Appe
ndix
B re
quire
ments
are a
pplic
able
to the
ISG
user
s in t
he fu
ture.
Thes
e re
quire
ments
are n
ot ap
plica
ble un
der t
his sc
ope o
f wor
k.
Prop
osed
Res
olut
ion:
Re
comm
end t
hat th
e ISG
clea
rly st
ate th
at the
App
endix
B
requ
ireme
nts do
not a
pply
or re
move
the r
efere
nce t
o RG
1.198
and
refer
ence
the e
ngine
ering
meth
ods f
or liq
uefac
tion a
nalys
is dir
ectly
.
Resp
onse
: Th
e poin
t of r
efere
ncing
RG-
1.198
was
to pr
ovide
gu
idanc
e with
resp
ect te
chnic
al me
thodo
logy.
The
Ma
rch 20
12 R
eque
st for
Infor
matio
n doe
s not
stipu
late t
hat A
ppen
dix B
requ
ireme
nts ap
ply to
re
spon
ses t
o the
infor
matio
n req
uest.
How
ever
, if
the an
alyse
s sub
mitte
d in r
espo
nse t
o the
requ
est fo
r inf
orma
tion a
re la
ter us
ed fo
r cer
tain l
icens
ing
purp
oses
, App
endix
B re
quire
ments
may
apply
. Ac
tion:
No
chan
ge to
text.
86
[J.W
. She
a, T
VA]
Loca
tion:
5.4.1
/page
52
Com
men
t: St
aff po
sition
-Suff
icien
t seis
mic m
argin
in ex
isting
stud
ies.
Conc
ern:
Su
fficien
t seis
mic m
argin
is no
t defi
ned.
Prop
osed
Res
olut
ion:
De
fine '
suffic
ient m
argin
" to b
e the
requ
ired f
actor
of sa
fety p
er F
eder
al Da
m Sa
fety R
egula
tor's
guida
nce.
This
term
occu
rs in
seve
ral p
laces
Resp
onse
: Su
fficien
t mar
gin is
usua
lly de
fined
in te
rms o
f a
safet
y fac
tor.
Actio
n:
Prov
ided r
efere
nce t
o FEM
A gu
idelin
es on
ea
rthqu
ake a
nalys
is of
dams
, whic
h disc
usse
s ap
prop
riate
factor
s of s
afety.
P
age
56 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
throu
ghou
t the d
ocum
ent.
88
[J.W
. She
a, T
VA]
Loca
tion:
5.5/p
age 5
4 Co
mm
ent:
Figur
e 16 -
appe
ars t
o hav
e a re
peat
in the
last
bulle
t Co
ncer
n:
Edito
rial
Prop
osed
Res
olut
ion:
Re
move
the r
epea
t bull
et or
corre
ct the
bulle
t if it
was m
eant
to be
a 3rd
po
int in
the f
igure
.
Resp
onse
: Th
ird bu
llet in
Figu
re 16
was
mea
nt to
read
: “G
roun
d moti
ons c
ausin
g fail
ure a
t Dam
3 ca
nnot
be
exclu
ded f
rom
caus
ing fa
ilure
at D
am 2”
Ac
tion:
Te
xt co
rrecte
d in F
igure
16.
89
[J.W
. She
a, T
VA]
Loca
tion:
5.6/pa
ge 56
Co
mm
ent:
Staff
posit
ion -D
am fa
ilure
due t
o an e
arthq
uake
shou
ld be
cons
idere
d for
both
the m
axim
um no
rmal
oper
ating
('full
-poo
l”) an
d ave
rage
re
servo
ir lev
els. N
orma
l, non
-flood
tailw
ater c
ondit
ions s
hould
be us
ed.
Conc
ern:
It i
s not
clear
wha
t is m
eant
by "m
axim
um no
rmal
pool'
. The
wate
r ele
vatio
n use
d in e
arthq
uake
load
case
is ge
nera
lly th
e nor
mal
oper
ating
leve
l. The
high
est n
orma
l ope
ratin
g lev
el is
used
whe
n the
re
are s
easo
nal fl
uctua
tions
of th
e res
ervo
ir.
Prop
osed
Res
olut
ion:
It i
s rec
omme
nded
that
the no
rmal
pool
level
with
norm
al tai
lwate
r leve
ls is
used
rathe
r tha
n max
imum
and a
vera
ge po
ol. T
he us
e of th
ese l
evels
ali
gns w
ith th
e TVA
(and
othe
r fed
eral
dam
regu
lator
s) da
m sa
fety
guida
nce f
or se
ismic
stabil
ity an
alysis
.
Resp
onse
: In
vie
w o
f th
e un
certa
intie
s in
volv
ed i
n es
timat
ing
rese
rvoi
r le
vels
tha
t m
ight
rea
sona
bly
be e
xpec
ted
to p
reva
il at
the
tim
e of
fai
lure
, th
e de
faul
t st
artin
g w
ater
sur
face
ele
vatio
n us
ed i
n flo
od r
outin
gs f
or
eval
uatio
n of
sei
smic
fai
lure
con
sequ
ence
s sh
ould
be
the
max
imum
nor
mal
poo
l ele
vatio
n (i.
e. t
op o
f ac
tive
stor
age
pool
). O
ther
sta
rting
wat
er s
urfa
ce
elev
atio
ns
may
be
us
ed,
with
ap
prop
riate
ju
stifi
catio
n.
Ju
stifi
catio
n sh
ould
be
ba
sed
on
oper
atin
g ru
les
and
oper
atin
g hi
stor
y of
th
e re
serv
oir.
The
ope
ratin
g hi
stor
y us
ed s
houl
d be
of
suffi
cien
t len
gth
to s
uppo
rt an
y co
nclu
sion
s dr
awn.
B
ut
cons
ider
atio
n sh
ould
be
gi
ven
to
poss
ible
in
stan
ces
whe
re t
he o
pera
ting
hist
ory
and/
or r
ules
ha
ve
been
in
fluen
ced
by
anom
alou
s co
nditi
ons
such
as
drou
ght.
P
age
57 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Actio
n:
Staff
posit
ion re
flecti
ng th
e pre
cedin
g disc
ussio
n ins
erted
in th
is se
ction
.
90
[J.W
. She
a, T
VA]
Loca
tion:
5.6/p
age 5
6 Co
mm
ent:
Staff
posit
ion -T
he flo
od an
d seis
mic c
ombin
ation
s to p
rovid
e a 1x
10-6
ha
zard
freq
uenc
y tar
get.
Conc
ern:
Th
is im
plies
that
a seis
mic f
ragil
ity an
alysis
is re
quire
d for
each
dam
and t
hen f
lood i
nflow
s be d
evelo
ped t
o rou
te wi
th the
failu
re of
the d
am.
This
requ
ires e
xtens
ive an
alysis
for a
comp
lex riv
er sy
stem
and i
s mor
e dif
ficult
to im
pleme
nt tha
n the
two d
eterm
inisti
c com
binati
ons t
hat a
re
defin
ed in
ANS
2.8.
Modif
ied A
NS 2.
8 com
binati
ons h
ave b
een
discu
ssed
with
the s
taff fo
r rep
lacem
ent o
f the d
eterm
inisti
c ear
thqua
ke
with
a pro
babil
istic
earth
quak
e.
Prop
osed
Res
olut
ion:
Re
comm
end g
uidan
ce in
clude
use o
f the m
odifie
d ANS
2.8
comb
inatio
ns th
at ha
ve pr
eviou
sly be
en di
scus
sed w
ith th
e staf
f.
Tho
se co
mbina
tions
are:
1) 1E
-04 g
roun
d moti
on co
mbine
d with
25
year
flood
and 2
) 1/2
of IE
-04 g
roun
d moti
on co
mbine
d with
less
er of
50
0 yea
r floo
d or 1
/2 PM
F.
Resp
onse
: St
aff po
sition
has b
een m
odifie
d to r
eflec
t the
modif
ied A
NS-2
.8 ap
proa
ch..
Actio
n:
Staff
posit
ion ha
s bee
n mod
ified t
o refl
ect th
e mo
dified
ANS
-2.8
appr
oach
..
91
[J.W
. She
a, T
VA]
Loca
tion:
6.2.1
/page
68
Com
men
t: Re
spon
se:
Staff
posit
ion ha
s cha
nged
to re
quire
analy
sis of
su
nny-d
ay fa
ilure
, so t
he co
mpre
hens
ive ris
k
P
age
58 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Th
e ISG
requ
ires a
comp
rehe
nsive
risk a
nalys
is to
asse
ss su
nny d
ay
failur
e mod
es.
Conc
ern:
Si
gnific
ant r
esou
rces w
ill be
requ
ired t
o com
plete
these
analy
ses.
All o
f TV
A da
ms do
not h
ave e
xistin
g Pote
ntial
Failu
re M
ode A
nalys
es
(PFM
A) co
mplet
ed ye
t. The
sche
dule
for th
e floo
d haz
ard r
eeva
luatio
n do
esn't
supp
ort th
is typ
e of a
nalys
is.
Prop
osed
Res
olut
ion:
Al
low us
e of s
impli
fied b
ut co
nser
vativ
e fail
ure m
odes
whe
n the
re is
a lac
k of a
n exis
ting P
FMA.
analy
sis to
show
nonfa
ilure
is no
long
er re
levan
t. Ac
tion:
Th
e disc
ussio
n of c
ompr
ehen
sive r
isk an
alysis
for
sunn
y-day
failu
re ha
s bee
n rem
oved
.
92
[J.W
. She
a, T
VA]
Loca
tion :
6.2.2
/page
69
Com
men
t: Th
e nor
mal p
ool e
levati
on (in
vert
of the
high
est o
utlet
or sp
illway
) de
finitio
n nee
ds cl
arific
ation
. Co
ncer
n:
This
is co
nfusin
g as i
t cou
ld be
defin
ed as
a sp
illway
sill e
levati
on w
hich
would
be si
gnific
antly
lowe
r tha
n nor
mal p
ool.
Pr
opos
ed R
esol
utio
n:
Sugg
est IS
G do
cume
nt be
revis
ed to
refle
ct a n
orma
l poo
l elev
ation
wh
ere r
eser
voir i
s main
taine
d for
norm
al op
erati
ons.
Resp
onse
: Th
e staf
f pos
ition h
as be
en m
odifie
d to b
e con
sisten
t wi
th oth
er st
ateme
nts ab
out in
itial w
ater le
vels.
The
de
fault w
ater le
vel is
max
imum
norm
al po
ol (to
p of
activ
e poo
l) or o
ther le
vel, w
ith ju
stific
ation
. Ac
tion:
St
aff p
ositi
on:
In v
iew
of
the
unce
rtain
ties
invo
lved
in
estim
atin
g re
serv
oir
leve
ls t
hat
mig
ht r
easo
nabl
y be
exp
ecte
d to
pre
vail
at t
he t
ime
of f
ailu
re,
the
defa
ult
star
ting
wat
er s
urfa
ce e
leva
tion
used
in
flood
rou
tings
for
ev
alua
tion
of o
verto
ppin
g sh
ould
be
the
max
imum
no
rmal
poo
l el
evat
ion
(i.e.
top
of
activ
e st
orag
e po
ol).
Oth
er s
tarti
ng w
ater
sur
face
ele
vatio
ns m
ay
be u
sed,
with
app
ropr
iate
just
ifica
tion.
Ju
stifi
catio
n sh
ould
be
base
d on
ope
ratin
g ru
les
and
oper
atin
g hi
stor
y of
the
rese
rvoi
r. T
he o
pera
ting
hist
ory
used
sh
ould
be
of
su
ffici
ent
leng
th
to
supp
ort
any
conc
lusi
ons
draw
n (e
.g.,
20 y
ears
or
mor
e).
But
P
age
59 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
cons
ider
atio
n sh
ould
be
give
n to
pos
sibl
e in
stan
ces
whe
re th
e op
erat
ing
hist
ory
and/
or ru
les
have
bee
n in
fluen
ced
by
anom
alou
s co
nditi
ons
such
as
dr
ough
t.
93
[J.W
. She
a, T
VA]
Loca
tion:
6.2.2
/page
69
Com
men
t: La
st bu
llet -
max
imum
obse
rved p
ool e
levati
on an
d max
imum
norm
al po
ol ele
vatio
n Co
ncer
n:
Thes
e ter
ms ar
e not
defin
ed in
the d
ocum
ent.
Prop
osed
Res
olut
ion:
Su
gges
t a de
finitio
n be a
dded
to IS
G do
cume
nt an
d/or p
rovid
e ex
ample
s.
Resp
onse
: Ma
ximum
norm
al po
ol ele
vatio
n is d
efine
d as t
he to
p of
activ
e stor
age.
Refer
ence
to m
axim
um ob
serve
d po
ol lev
el is
no lo
nger
used
. Ac
tion:
St
aff po
sition
now
read
s: In
vie
w o
f th
e un
certa
intie
s in
volv
ed i
n es
timat
ing
rese
rvoi
r le
vels
tha
t m
ight
rea
sona
bly
be e
xpec
ted
to p
reva
il at
the
tim
e of
fai
lure
, th
e de
faul
t st
artin
g w
ater
sur
face
ele
vatio
n us
ed i
n flo
od r
outin
gs f
or
eval
uatio
n of
ove
rtopp
ing
shou
ld b
e th
e m
axim
um
norm
al p
ool
elev
atio
n (i.
e. t
op o
f ac
tive
stor
age
pool
). O
ther
sta
rting
wat
er s
urfa
ce e
leva
tions
may
be
use
d, w
ith a
ppro
pria
te ju
stifi
catio
n.
Just
ifica
tion
shou
ld b
e ba
sed
on o
pera
ting
rule
s an
d op
erat
ing
hist
ory
of th
e re
serv
oir.
The
ope
ratin
g hi
stor
y us
ed
shou
ld
be
of
suffi
cien
t le
ngth
to
su
ppor
t an
y co
nclu
sion
s dr
awn
(e.g
., 20
yea
rs o
r m
ore)
. B
ut
cons
ider
atio
n sh
ould
be
give
n to
pos
sibl
e in
stan
ces
whe
re th
e op
erat
ing
hist
ory
and/
or ru
les
have
bee
n in
fluen
ced
by
anom
alou
s co
nditi
ons
such
as
dr
ough
t.
94
Loca
tion:
7.1/pa
ge 70
Re
spon
se:
P
age
60 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
[J.W
. She
a, T
VA]
Com
men
t: 4th b
ullet
– los
s of g
ener
ation
by flo
oding
of sw
itchy
ard.
Conc
ern:
In
most
case
s the
tail d
eck c
ontro
ls wh
en ge
nera
tion i
s stop
ped.
Switc
hyar
d is u
suall
y at a
high
er el
evati
on th
an th
e tail
deck
(the
point
at
which
the p
ower
hous
e is f
loode
d due
to hi
gh ta
ilwate
r).
Prop
osed
Res
olut
ion:
Su
gges
t inco
rpor
ating
the c
onsid
erati
on of
loss
of th
e swi
tchya
rd or
the
powe
rhou
se du
e to f
loodin
g, wh
ichev
er is
at a
lower
elev
ation
.
The o
bser
vatio
n is c
orre
ct.
Actio
n:
Modif
ied st
ateme
nt to
refle
ct los
s of p
ower
hous
e, or
sw
itchy
ard.
This
discu
ssion
is no
w in
Secti
on 4.
7.2.1.
95
[J.W
. She
a, T
VA]
Loca
tion:
10.1.
2 and
10.2
/pag
es 82
-84
Co
mm
ent:
NRC
prefe
rs us
e of 2
-D an
alysis
over
a 1-
D an
alysis
. Co
ncer
n:
Effor
ts to
addr
ess t
he is
sues
disc
usse
d in t
his se
ction
can h
ave a
sig
nifica
nt im
pact
on th
e tim
e req
uired
to co
nduc
t the a
nalys
es. E
ffort
to de
velop
and c
alibr
ate a
2-D
mode
l is w
ell be
yond
that
for a
1-D
mode
l and
the c
urre
nt ha
zard
reev
aluati
on an
alysis
sche
dule
does
not
supp
ort a
2-D
analy
sis fo
r a la
rge a
nd co
mplic
ated r
iver s
ystem
. Pr
opos
ed R
esol
utio
n:
TVA
inten
ds to
use a
1-D
HECR
AS an
alysis
. Rec
omme
nd gu
idanc
e inc
lude a
listin
g of 1
-D an
d 2-D
mod
els fo
r whic
h app
ropr
iate a
nalys
es
have
been
revie
wed a
nd ap
prov
ed by
NRC
staff
.
Resp
onse
: Th
e ISG
does
not p
ropo
se 2D
analy
sis fo
r the
entire
wa
tersh
ed or
river
syste
m. 2
D an
alysis
is pr
opos
ed
for ca
ses w
here
it ma
y hav
e a si
gnific
ant e
ffect
on
calcu
lation
of in
unda
tion w
ater le
vel a
nd ve
locitie
s at
the N
PP si
te. T
he N
RC do
es no
t end
orse
spec
ific
mode
ling s
oftwa
re. T
he us
e of a
partic
ular p
acka
ge
shou
ld be
justi
fied b
y the
licen
see.
Actio
n:
No ch
ange
to te
xt.
P
age
61 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
96
[K. C
anva
n, E
PRI]
Loca
tion:
Sec
tion
1.4.2,
from
pag
e 56
Mod
elin
g C
onse
quen
ces o
f Sei
smic
Dam
Fai
lure
“G
iven
the
haza
rd fr
eque
ncy
targ
et o
f 1x1
0-6
disc
usse
d in
Se
ctio
n 1.
4.2,
the
dam
failu
re fl
ood
wav
e at
the
site
shou
ld b
e co
mbi
ned
with
flow
s of a
freq
uenc
y th
at re
sult
in a
com
bine
d an
nual
pro
babi
lity
of lx
1 0-
6. F
or e
xam
ple,
if th
e da
m fa
ils u
nder
a
10-4
gro
und
mot
ion;
com
bine
the
dam
bre
ak fl
ood
wav
e w
ith a
10
0-ye
ar fl
ood.
If th
e da
m fa
ils u
nder
a 1
0-3
grou
nd m
otio
n,
com
bine
the
dam
bre
ak fl
ood
wav
e it
with
a 1
000-
year
floo
d."
Com
men
t: Th
e co
mbi
ning
of a
n ea
rthqu
ake
and
a flo
od b
y si
mpl
y m
ultip
lyin
g th
eir a
nnua
l pro
babi
litie
s of o
ccur
renc
e do
es n
ot
allo
w fo
r the
ver
y sm
all d
urat
ion
with
in a
yea
r for
the
earth
quak
e to
coi
ncid
e w
ith a
long
er b
ut st
ill o
nly
a fa
irly
smal
l fra
ctio
n of
a
year
for t
he d
urat
ion
of m
ost f
lood
s.
Prop
osed
Res
olut
ion:
R
ecom
men
d co
nsid
erat
ion
of m
etho
dolo
gy in
: Eve
nt
Com
bina
tion
Ana
lysi
s for
Des
ign
and
Reh
abili
tatio
n of
U.S
. A
rmy
Cor
ps o
f Eng
inee
rs N
avig
atio
n St
ruct
ures
by
Bru
ce R
. El
lingw
ood,
Con
tract
Rep
ort I
TL-9
5-2,
July
199
5, U
S A
rmy
Cor
ps o
f Eng
inee
rs, W
ater
way
s Exp
erim
ent S
tatio
n.
Resp
onse
: Se
ction
1.4.2
has b
een r
evise
d to r
emov
e this
ap
proa
ch of
comb
ining
earth
quak
e and
flood
. See
re
spon
se to
comm
ent 3
9 Ac
tion:
Se
e res
pons
e to c
omme
nt 39
.
97
[K. C
anva
n, E
PRI]
Loca
tion:
Pag
e 76
"How
ever
, the
ir pa
per d
oes n
ot p
rovi
de c
lear
crit
eria
for
sele
ctin
g th
e er
odib
ility
inde
x."
Com
men
t: X
u an
d Zh
ang
(200
9) d
o no
t pro
vide
det
aile
d cr
iteria
for
sele
ctin
g th
e er
odib
ility
inde
x be
caus
e th
ey st
ate
that
they
use
d
Resp
onse
: Sa
me as
comm
ent 6
6 [J.
Riley
]. See
resp
onse
to
comm
ent 6
6 Ac
tion:
Se
e res
pons
e to c
omme
nt 66
P
age
62 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
defin
ition
s in
a pa
per b
y B
riaud
, whi
ch p
rovi
des d
etai
led
defin
ition
s.
98
[K. C
anva
n, E
PRI]
Loca
tion:
pag
e 76
- "I
n ad
ditio
n, a
necd
otal
evi
denc
e su
gges
ts
that
thei
r rel
atio
n fo
r fai
lure
tim
e m
ay b
e bi
ased
in
favo
r of l
onge
r tim
es (W
ahl,
2013
)."
Com
men
t: X
u an
d Zh
ang
defin
e fa
ilure
tim
e di
ffer
ently
than
in o
ther
em
piric
al b
reac
h pa
ram
eter
stud
ies.
This
mea
ns th
at o
ne m
ust
use
thei
r fai
lure
tim
e es
timat
es in
a b
reac
h m
odel
(e.g
. HEC
-R
AS)
in a
way
that
is c
onsi
sten
t with
thei
r def
initi
on. I
t is n
ot a
fu
ndam
enta
l def
icie
ncy
or fl
aw in
the
met
hod.
Resp
onse
: Sa
me as
comm
ent 6
7 [J.
Riley
]. See
resp
onse
to
comm
ent 6
7 Ac
tion:
Se
e res
pons
e to c
omme
nt 67
99
[K. C
anva
n, E
PRI]
Loca
tion:
pag
es 7
7 an
d 78
- Se
ctio
n 8.
2.2.
1, U
ncer
tain
ty in
Pr
edic
ted
Bre
ach
Para
met
ers a
nd H
ydro
grap
hs a
nd S
ectio
n 8.
2.2.
2, P
erfo
rmin
g Se
nsiti
vity
Ana
lyse
s to
Sele
ct B
reac
h Pa
ram
eter
s. Co
mm
ent:
It is
use
ful t
o re
cogn
ize
that
"un
certa
inty
" in
re
gres
sion
equ
atio
ns is
ass
ocia
ted
with
"un
expl
aine
d va
rianc
e"
and
that
phy
sica
l arg
umen
ts/e
ngin
eerin
g ju
stifi
catio
ns c
an b
e m
ade
as to
whe
re in
the
rang
e of
"un
certa
inty
" a
parti
cula
r dam
w
ould
be
expe
cted
to fi
t giv
en it
s phy
sica
l cha
ract
eris
tics t
hat a
re
not s
peci
fical
ly in
clud
ed in
the
"exp
lain
ed v
aria
nce"
repr
esen
ted
by th
e m
athe
mat
ical
form
of t
he re
gres
sion
equ
atio
n. T
here
fore
it
may
not
be
appr
opria
te to
per
form
sens
itivi
ty a
naly
ses o
ver t
he
entir
e ra
nge
of u
ncer
tain
ty o
n pr
edic
ted
brea
ch p
aram
eter
s (or
pr
edic
ted
peak
bre
ach
flow
rate
s).
Resp
onse
: Sa
me as
comm
ent 6
8 [J.
Riley
]. See
resp
onse
to
comm
ent 6
8 Ac
tion:
No
chan
ge to
text.
100
[M. M
cCan
n]
Gen
eral
Com
men
t
This
is a
n im
porta
nt IS
G fo
r the
NR
C a
nd fo
r the
dam
s in
dust
ry. T
he
Resp
onse
:
P
age
63 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Sta
ff ha
s do
ne a
goo
d jo
b in
pul
ling
it to
geth
er in
a s
hort
perio
d of
tim
e.
No
ne
Actio
n:
None
101
[M. M
cCan
n]
Gen
eral
Com
men
t
The
docu
men
t see
ms
to d
eal w
ith p
art o
f the
pro
blem
ass
ocia
ted
with
da
ms
upst
ream
of N
PP
– S
cree
ning
Ana
lysi
s an
d th
e as
sess
men
t of
flood
ing
at N
PP
site
s. It
doe
s no
t rea
lly a
ddre
ss th
e is
sue
of h
ow th
e ev
alua
tion
of d
am(s
) sho
uld
be c
arrie
d ou
t whe
n th
ey p
ose
a flo
od
thre
at to
a N
PP
.
Resp
onse
: Tr
ue st
ateme
nt. D
etaile
d guid
ance
on st
ructu
ral
analy
sis un
der v
ariou
s loa
ding c
ases
is be
yond
the
scop
e of th
e ISG
. Lo
ok in
to pr
ovidi
ng ge
nera
l guid
ance
, with
re
feren
ces p
ointin
g to m
ore d
etaile
d guid
ance
by
USBR
, USA
CE, F
ERC.
Ac
tion:
TB
D
102
[M. M
cCan
n]
Gen
eral
Com
men
t
From
my
read
of t
he d
raft,
it a
ppea
rs th
ere
is a
mix
ed m
essa
ge w
ith
rega
rd to
the
use
of d
eter
min
istic
and
pro
babi
listic
met
hods
. Thi
s is
, as
a m
inim
um, c
onfu
sing
for t
he p
lant
ow
ner,
tryin
g to
dec
ide
how
to
appr
oach
this
pro
blem
. It s
eem
s to
me
the
Sta
ff ne
eds
to p
rese
nt a
cl
ear a
nd c
onci
se d
irect
ion
and
guid
ance
for d
ealin
g w
ith th
is is
sue.
Resp
onse
: Th
e ISG
focu
ses o
n pro
babil
istic
appr
oach
es fo
r tho
se m
echa
nisms
for w
hich p
roba
bilist
ic an
alysis
is
stand
ard e
ngine
ering
prac
tice (
e.g., s
eismi
c haz
ard)
.Pr
obab
ilistic
appr
oach
es fo
r esti
matin
g the
extre
me
rainf
all an
d floo
d eve
nts of
inter
est in
this
ISG
(e.g.
1e-4
pe
r yr o
r lowe
r ann
ual e
xcee
danc
e pro
babil
ity) e
xist, b
ut the
re ar
e no i
ndus
try co
nsen
sus s
tanda
rds o
r fed
eral
guida
nce t
hat d
efine
curre
nt ac
cepte
d pra
ctice
. Sim
ilarly
for
sunn
y-day
failu
re.
The N
RC is
curre
ntly i
nves
tigati
ng P
FHA
metho
ds,
with
the in
tentio
n of in
corp
orati
ng pr
obab
ilistic
me
thodo
logies
for f
lood h
azar
d esti
matio
n into
its
regu
lator
y fra
mewo
rk, w
here
appli
cable
.
P
age
64 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
Actio
n:
No ch
ange
to te
xt.
103
[M. M
cCan
n]
Gen
eral
Com
men
t
From
my
read
of t
he d
ocum
ent,
it se
ems
as if
the
Sta
ff is
tryi
ng to
take
a
risk-
info
rmed
app
roac
h to
this
pro
blem
(at l
east
for p
arts
of t
he
prob
lem
) – w
hich
I be
lieve
is a
ppro
pria
te. H
owev
er, t
his
is n
ot c
lear
ly
stat
ed a
t the
beg
inni
ng a
nd n
ot fu
lly c
arrie
d ou
t.
Resp
onse
: Re
spon
se to
this
comm
ent is
same
as th
e pre
vious
co
mmen
t. Ac
tion:
No
chan
ge to
text.
104
[M. M
cCan
n]
Gen
eral
Com
men
t
I sug
gest
car
e be
take
n in
refe
rrin
g/ad
optin
g ex
istin
g do
cum
enta
tion
and
met
hods
dev
elop
ed b
y ot
hers
. The
re a
re a
t lea
st fe
w e
xam
ples
w
here
refe
renc
e is
mad
e to
met
hods
of o
ther
s th
at I
belie
ve w
ould
not
m
eet c
urre
nt N
RC
requ
irem
ents
.
Resp
onse
: Th
e pur
pose
of th
is IS
G is
to pr
ovide
guida
nce t
o lic
ense
es w
hen r
espo
nding
to th
e 50.5
4(f)
Requ
est
for In
forma
tion.
The
requ
ireme
nts fo
r res
pond
ing to
an
infor
matio
n req
uest
are n
ot ne
cess
arily
the s
ame
as th
e req
uirem
ents
impo
sed f
or lic
ensin
g acti
ons.
Actio
n:
No ch
ange
to te
xt.
105
[M. M
cCan
n]
Gen
eral
Com
men
t
Sta
ff po
sitio
ns a
re o
ften
over
ly w
ordy
and
/or c
onfu
sing
. I s
ugge
st th
e po
sitio
ns b
e re
view
ed c
lose
ly a
nd w
ritte
n in
a m
anne
r tha
t con
cise
ly
stat
es w
hat t
he S
taff’
s po
sitio
n is
. Spe
cific
com
men
ts la
ter w
ill po
int t
o th
is d
irect
ly.
Resp
onse
: W
ill re
view
docu
ment
for cl
arity
. Ac
tion:
W
ill re
view
docu
ment
for cl
arity
.
106
[M. M
cCan
n]
Gen
eral
Com
men
t
Ther
e ar
e a
num
ber o
f inc
onsi
sten
cies
in th
e S
taff
posi
tions
take
n w
ith
othe
r NR
C p
ositi
ons.
For
inst
ance
, why
is u
se o
f the
US
GS
sei
smic
ha
zard
ana
lysi
s ap
prop
riate
for t
he a
naly
sis
of g
roun
d m
otio
ns a
t dam
Resp
onse
: Ta
lk to
seism
ic fol
ks ab
out th
is….
Actio
n:
P
age
65 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
site
s w
hen
it is
una
ccep
tabl
e fo
r the
eva
luat
ion
grou
nd m
otio
n ha
zard
at
NPP
site
s?
107
[M. M
cCan
n]
Sect
ion
1.4.
2, p
. 7, 8
Sta
ff Po
sitio
ns
Firs
t Pos
ition
-In
gene
ral,
both
the
prob
abili
ty o
f the
haz
ard
and
the
capa
city
/frag
ility
of t
he d
am w
ould
fact
or in
to th
e fa
ilure
like
ho
od d
eter
min
atio
n. H
owev
er, t
o th
e ex
tent
that
the
dam
ca
paci
ty o
r fra
gilit
y is
not
kno
wn,
mor
e w
eigh
t mus
t be
plac
ed
on th
e ha
zard
pro
babi
lity.
The
refo
re, t
he h
azar
d pr
obab
ility
ta
rget
for j
udgi
ng th
e lik
elih
ood
of a
par
ticul
ar fa
ilure
m
ode/
scen
ario
(eith
er fr
om a
sing
le h
azar
d or
app
ropr
iate
co
mbi
natio
n) is
1 x
10-6
ann
ual e
xcee
d pr
obab
ility
with
ju
stifi
catio
n (i.
e., d
am fa
ilure
may
be
excl
uded
from
furt
her
cons
ider
atio
n if
it ca
n be
show
n by
a d
am sp
ecifi
c en
gine
erin
g as
sess
men
t tha
t the
pro
babi
lity
of fa
ilure
is 1
x10-6
per
yea
r or
less
usi
ng c
urre
nt b
est p
ract
ices
). …
……
……
……
……
. Th
is p
ositi
on se
ts th
e st
age
for a
num
ber o
f the
pos
ition
s tha
t ha
ve b
een
laid
out
, so
it is
qui
te im
porta
nt. A
n ov
erar
chin
g co
ncep
t tha
t is b
eing
pro
mot
ed is
the
idea
of s
cree
ning
on
the
basi
s of h
azar
d. A
s an
appr
oach
this
can
be
viab
le. H
owev
er, t
he
inte
nt o
r cla
im th
is is
not
the
appr
oach
that
is b
eing
take
n. F
or
inst
ance
, whe
n yo
u sa
y th
e ut
ility
can
eva
luat
e a
dam
for a
10-4
gr
ound
mot
ion
and
show
ther
e is
suff
icie
nt m
argi
n, e
tc.;
this
is
not a
haz
ards
bas
ed a
ppro
ach,
nor
is it
an
appr
oach
that
pla
ces
mor
e w
eigh
t on
the
haza
rd. I
n fa
ct, i
t is p
laci
ng a
gre
at d
eal o
f w
eigh
t on
frag
ility
of t
he d
am. S
o m
uch
so, t
hat a
stan
dard
has
be
en se
t tha
t the
mar
gin
muc
h be
so g
reat
that
a ri
sk re
duct
ion
of
a fa
ctor
of 1
00 m
ust b
e pr
ovid
ed b
y th
e da
m. T
his i
s unl
ikel
y to
oc
cur.
Resp
onse
: Th
is se
ction
and t
he st
aff po
sition
s hav
e bee
n mo
dified
to re
flect
the pr
actic
al dif
ficult
y of e
stima
ting
haza
rds a
t the 1
e-6 a
nnua
l exc
eeda
nce p
roba
bility
. Ac
tion:
Se
ction
1.4.2
has b
een m
odifie
d as d
escri
bed i
n the
re
spon
se to
comm
ent 3
9 [J.
Riley
]
P
age
66 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
My
sugg
estio
n w
ould
be
that
you
stat
e w
hat i
t is y
ou a
re re
ally
do
ing
and
wha
t you
are
tryi
ng to
ach
ieve
(I th
ink
you
are
taki
ng
a ris
k-in
form
ed a
ppro
ach)
. A
cou
ple
of q
uest
ions
rega
rdin
g th
is p
ositi
on:
a.
Wha
t doe
s the
follo
win
g m
ean
- for
judg
ing
the
likel
ihoo
d of
a
part
icul
ar fa
ilure
mod
e/sc
enar
io.
b.
In th
e ab
ove
quot
e, w
hat d
oes ‘
judg
ing
the
likel
ihoo
d’
mea
n?
c.
Ditt
o –
Wha
t doe
s ‘pa
rticu
lar f
ailu
re m
ode/
scen
ario
’ mea
n?
Doe
s thi
s mea
n a
sing
le fa
ilure
mod
e du
e to
seis
mic
lo
adin
g? D
oes i
t mea
n al
l fai
lure
mod
es fo
r sei
smic
load
ing?
W
hat t
his r
eally
com
es d
own
to is
– w
hat d
oes t
he 1
0-6 re
ally
ap
ply
to?
For i
nsta
nce,
if th
ere
are
10 in
depe
nden
t sei
smic
fa
ilure
mod
es th
at le
ad to
unc
ontro
lled
rele
ase
of a
rese
rvoi
r (th
at p
oses
a p
robl
em fo
r a N
PP),
does
10-6
app
ly to
eac
h fa
ilure
mod
e, to
the
sum
?
109
[M. M
cCan
n]
Sect
ion
1.4.
2, p
. 7, 8
Sta
ff Po
sitio
ns
Seco
nd P
ositi
on -
Whe
n co
nsid
erin
g hy
drol
ogic
failu
re d
ue to
la
rge
flood
s, ex
trem
e ca
utio
n sh
ould
be
exer
cise
d w
ith re
gard
to
atte
mpt
s to
estim
ate
the
prob
abili
ty o
f det
erm
inis
tic e
stim
ates
su
ch a
s the
pro
babl
e m
axim
um p
reci
pita
tion
(PM
P) o
r pro
babl
e m
axim
um fl
ood
(PM
F). M
etho
ds th
at in
volv
e ex
trem
e ex
trap
olat
ion
of d
istr
ibut
ions
such
as l
og- P
ears
on a
nd o
ther
s ba
sed
on li
mite
d da
ta w
ill b
e vi
ewed
with
gre
at sk
eptic
ism
.
Resp
onse
: Ag
ree w
ith re
spec
t to co
mmen
t on e
xtrap
olatio
n. W
ith re
spec
t to co
mmen
t on U
SBR
best
prac
tices
, the
requ
ireme
nts fo
r res
pond
ing to
an in
forma
tion
requ
est a
re no
t nec
essa
rily th
e sam
e as t
hose
for a
lic
ensin
g acti
on (e
.g. w
here
RG
1.200
requ
ireme
nts
P
age
67 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
I am
a b
it pu
zzle
d by
this
pos
ition
. It s
eem
s to
me
phra
ses
like
‘cau
tion
shou
ld b
e ex
erci
sed’
, ‘vi
ewed
with
gre
at s
kept
icis
m’ a
re n
ot c
onsi
sten
t w
ith th
e no
tion
of p
rovi
ding
gui
danc
e. I
wou
ld re
com
men
d th
at a
mor
e di
rect
, pos
itive
sta
tem
ent b
e m
ade
here
. As
it st
ands
it s
eem
s to
me
to
lead
to c
onfu
sion
for u
tiliti
es. M
y re
adin
g of
this
pos
ition
is s
impl
e –
you
will
not
acc
ept e
xtra
pola
tion
or p
oint
est
imat
es o
f the
pro
babi
lity
of
fictit
ious
larg
e ev
ents
like
the
PM
F. If
this
, or s
omet
hing
like
it is
wha
t yo
u m
ean,
then
I th
ink
you
shou
ld s
ay in
a s
impl
e, s
traig
ht fo
rwar
d m
anne
r. W
ith th
e w
ordi
ng y
ou h
ave
chos
en, y
ou le
ave
the
door
ope
n fo
r the
ana
lyst
. My
own
view
is, t
hese
app
roac
hes
you
refe
r to
have
no
plac
e in
a ri
sk-in
form
ed e
valu
atio
n of
a N
PP
. Sim
ilarly
, if t
here
is
som
ethi
ng y
ou w
ould
acc
ept,
say
it as
wel
l.
The
posi
tion
that
the
US
BR
Bes
t Pra
ctic
es is
an
acce
ptab
le a
ppro
ach
mig
ht b
e co
nsid
ered
in th
e fo
llow
ing
cont
ext.
If on
e w
ere
to a
sk th
e qu
estio
n as
to w
heth
er o
r not
thes
e pr
actic
es s
atis
fy th
e P
RA
sta
ndar
d fo
r Cat
egor
y 2
(see
als
o R
G 1
.200
), on
e w
ould
con
clud
e th
at th
ey d
o no
t. A
s su
ch, i
t see
ms
from
a n
ucle
ar re
gula
tory
per
spec
tive
that
thei
r ‘b
est’
is n
ot a
dequ
ate.
You
mig
ht re
-con
side
r thi
s po
sitio
n.
would
apply
). Ac
tion:
Th
is lan
guag
e reg
ardin
g extr
apola
tion h
as be
en
remo
ved f
rom
the IS
G.
110
[M. M
cCan
n]
Sect
ion
1.4.
2, p
. 7, 8
Sta
ff Po
sitio
ns
Thir
d Po
sitio
n - W
hen
cons
ider
ing
seis
mic
dam
failu
re a
nd
prob
abili
stic
seis
mic
haz
ard
asse
ssm
ent (
PSH
A), i
t is i
mpo
rtan
t to
not
e th
at th
e ha
zard
of i
nter
est t
o th
e N
PP is
a c
atas
trop
hic
failu
re re
sulti
ng in
unc
ontr
olle
d re
leas
e of
the
rese
rvoi
r, no
t lo
wer
leve
ls o
f dam
age
that
may
deg
rade
the
serv
ices
that
the
dam
pro
vide
s. It
is a
lso
reco
gniz
ed th
at th
e se
ism
ic d
esig
n of
da
ms t
ypic
ally
incl
udes
sign
ifica
nt m
argi
ns a
nd fa
ctor
s of s
afet
y.
In o
rder
to a
ccou
nt fo
r thi
s lev
el o
f mar
gin
befo
re fa
ilure
, it
acce
ptab
le to
use
the
1x10
-4 a
nnua
l fre
quen
cy g
roun
d m
otio
ns,
at sp
ectr
al fr
eque
ncie
s im
port
ant t
o th
e da
m, f
or se
ism
ic
eval
uatio
n of
dam
s, in
stea
d of
1x1
0-6,
as d
iscu
ssed
abo
ve.
How
ever
, app
ropr
iate
eng
inee
ring
just
ifica
tion
mus
t be
prov
ided
Resp
onse
: In
dust
ry c
onse
nsus
sta
ndar
ds a
nd fe
dera
l gui
danc
e fo
r a ri
sk-in
form
ed fr
amew
ork
for a
ll as
pect
s in
the
eval
uatio
n of
dam
s do
es n
ot c
urre
ntly
exi
st.
Actio
n:
Need
furth
er di
scus
sion w
ith N
RC se
ismic
staff.
P
age
68 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
to sh
ow th
at th
e da
m h
as su
ffici
ent s
eism
ic m
argi
n. O
ther
wis
e th
e 1x
10-6
gro
und
mot
ions
shou
ld b
e us
ed.
As
I hav
e co
mm
ente
d pr
evio
usly
, the
use
of t
he 1
0-4 g
roun
d m
otio
n an
d ‘s
uffic
ient
’ mar
gin
will
not m
eet y
our g
oal o
f 10-6
. For
exa
mpl
e, if
a
utilit
y sh
ows
they
hav
e a
fact
or o
f saf
ety
of 1
.5 (a
larg
e m
argi
n in
the
seis
mic
ana
lysi
s fo
r dam
s), o
ne c
ould
read
ily s
how
this
will
not
be
equi
vale
nt to
the
eval
uatio
n at
the
10-6
gro
und
mot
ion.
I su
gges
t som
e ba
ckgr
ound
wor
k be
don
e to
est
ablis
h an
app
roac
h th
at w
ill be
in
tern
ally
con
sist
ent a
nd m
eet t
he s
tand
ard
you
are
setti
ng.
The
term
suf
ficie
nt m
argi
n is
vag
ue a
nd w
ill b
e co
nfus
ing
for t
he
anal
yst.
Ther
e is
a d
icho
tom
y w
ith re
gard
to p
ositi
ons
1, 2
and
3 fo
r sei
smic
an
d hy
drol
ogic
failu
res.
I po
sitio
n 1
a ty
pe o
f ris
k-in
form
ed a
ppro
ach
is
bein
g ta
ken.
In p
ositi
on 2
, effe
ctiv
ely
no p
ositi
on is
bei
ng ta
ken
othe
r th
an to
say
‘ext
rem
e ca
utio
n’ s
houl
d be
use
d……
…. W
hy n
ot e
stab
lish
a ris
k-in
form
ed fr
amew
ork
for a
ll as
pect
s in
the
eval
uatio
n of
dam
s?
111
[M. M
cCan
n]
Sect
ion
5.1.
3, p
. 45
In g
ener
al I
find
this
sec
tion
to b
e a
dist
ract
ion
and
mis
lead
ing.
It is
a d
istra
ctio
n be
caus
e th
e de
term
inis
tic a
naly
sis
has
no re
leva
nce
to th
e is
sue
bein
g ad
dres
sed
and
the
Sta
ff’s
posi
tion
on th
is s
ubje
ct.
The
refe
renc
es to
the
USG
S a
re n
ot re
leva
nt o
r sup
porti
ve o
f the
S
taff’
s go
als.
It is
mis
lead
ing
beca
use
of th
e af
orem
entio
ned
dist
ract
ion
and
the
impl
icat
ions
that
can
be
deriv
ed fr
om th
e st
atem
ent;
“For
tuna
tely
, m
uch
of th
is w
ork
has
alre
ady
been
don
e by
the
US
GS,
whi
ch h
as
prod
uced
map
s fo
r the
ent
ire U
.S. (
US
GS
, 200
8).”
The
fact
of t
he
mat
ter i
s, th
e U
SG
S m
aps
do n
ot m
eet t
he c
urre
nt s
tand
ard
of p
ract
ice
(am
ong
othe
r thi
ngs
they
do
not e
valu
ate
epis
tem
ic u
ncer
tain
ties
appr
opria
tely
(or a
t all
in s
ome
case
s)).
The
US
GS
map
s ar
e no
t an
acce
ptab
le b
asis
for i
nput
to e
stim
atin
g ris
ks to
nuc
lear
pow
er p
lant
s.
Rel
ativ
e to
the
Sta
ff po
sitio
n on
this
topi
c, I
wou
ld re
com
men
d th
at th
e
Resp
onse
: Ag
ree t
hat d
iscus
sion o
f dete
rmini
stic a
ppro
ache
s is
not n
eede
d. T
he re
feren
ce to
the U
SGS
maps
is a
vesti
ge of
an ea
rlier v
ersio
n of th
e doc
umen
t that
discu
ssed
using
the U
SGS
maps
as a
scre
ening
too
l. Ac
tion:
Se
ction
rena
med t
o “Pr
obab
ilistic
Seis
mic H
azar
d An
alysis
” Pa
ragr
aph o
n dete
rmini
stic a
nalys
is re
move
d. Re
feren
ce to
USG
S ma
ps ha
s bee
n rem
oved
.
P
age
69 o
f 70
Com
men
t No.
C
omm
ent
DR
AFT
NR
C R
espo
nse
posi
tion
be w
orde
d in
suc
h a
man
ner t
hat i
t is
cons
iste
nt w
ith th
e N
RC
’s p
ositi
on w
ith re
spec
t to
PS
HA
and
the
asse
ssm
ent o
f pla
nt ri
sk.
112
[M. M
cCan
n]
Sect
ion
5.3,
p. 4
8
The
proc
ess
outli
ned
in F
igur
e 15
see
ms
reas
onab
le, b
ut m
ay b
e a
bit
prob
lem
atic
in p
ract
ice.
For
inst
ance
, wha
t is
mea
nt b
y D
ocum
ente
d M
argi
n/Fa
ctor
of S
afet
y? in
the
cont
ext o
f the
Sta
ff’s
posi
tion
(i.e.
, 10-6
) an
d th
e us
e of
10-4
. As
I men
tione
d in
my
prev
ious
com
men
ts, I
thin
k a
licen
see
coul
d ac
tual
ly s
how
som
e le
vel o
f mar
gin/
fact
or o
f saf
ety
(i.e.
, m
eets
a C
orps
sta
ndar
d) a
nd fa
ll sh
ort o
f an
acce
ptab
le fr
eque
ncy
of
dam
failu
re. D
o yo
u ha
ve a
bas
is fo
r the
app
roac
h yo
u ar
e pr
opos
ing
and
mor
e im
porta
ntly
do
you
have
a b
asis
to s
how
that
it w
ill w
ork.
From
a p
ract
ical
per
spec
tive
ther
e ar
e qu
estio
ns li
ke:
M
argi
n re
lativ
e to
wha
t – th
e M
CE
?, th
e 10
-4 (
this
of c
ours
e be
com
es a
chi
cken
and
egg
thin
g), e
tc.,
D
o yo
u ha
ve g
uida
nce
for w
hat a
mou
nt o
f mar
gin
is e
noug
h?
S
tatin
g th
e pr
ior b
ulle
t diff
eren
tly, d
o yo
u kn
ow w
hat m
argi
n w
ill be
con
sist
ent w
ith a
10-4
gro
und
mot
ion
leve
l and
a ri
sk
redu
ctio
n of
a fa
ctor
of 1
00?
With
rega
rd to
the
Sta
ff po
sitio
n, I
do n
ot a
gree
with
the
refe
renc
e to
us
ing
the
USG
S to
ols
and
mod
els
for d
evel
opin
g th
e 10
-4 g
roun
d m
otio
ns fo
r rea
sons
sta
ted
abov
e an
d in
my
prev
ious
com
men
t.
Resp
onse
: IS
G ha
s bee
n mod
ified t
o rem
ove t
he 1e
-6 cr
iteria
for
seism
ic ha
zard
. 1e-
4 is t
he ha
zard
targ
et.
Ask s
eismi
c folk
s abo
ut ob
jectio
n to U
SGS
tools…
Ac
tion:
P
age
70 o
f 70