# Remedial Action Report for 

# Sola Optical USA, Inc. Superfund Site Sonoma County, California May 11, 2012

Prepared By: U.S. Environmental Protection Agency

Region IX 75 Hawthorne Street San Francisco, California 94105

Approved by:

Mic el Montgomery, Assistant Director Fe ral Facilities and Cleanup Branch Superfund Division EPA Region IX Date 

### SDMS DOCID# 1133116I 

## TAB LE O F CON T EN T S

T ab l e o f C o n t

en ts

......................................................................................................................... I

A c r o n y ms ....................................................................................................................................III

I. In t r o du cti on

........................................................................................................................................ 1 Lo cat i o n , s i ze, e n v i ro n m e n ta l sett i n g, l a n d a n d r e s o ur ce u se

............................................................. 1 Op e r at i o n a l h i st or y a n d w aste m

a n age m e n t pr a ct i ce s

........................................................................ 2 R eg u l at or y a n d e nf or c e m e n t h i st or y, S i t e i n vest i gat i o n a ct i v i t i es a n d m a j or fin d i n

gs , P r i or R e mo va l a n d r e m e d i a l a ct i v i t i e s

............................................................................................................. 2 Op e r ab l e U n i t s D es i g n a t e d

, Op e r ab l e U n i t A p p li c ab l e t o t h i s R A R e por t

....................................... 4



### II. O perab l e U n it B a

c k g r o und

................................................................................................. 5 R e q u i r e m e n t s Sp ec i fi e d i n t h e RO D f or t h e O U

.................................................................................... 5 B as i s f or C l ea n u p Go a l s

............................................................................................................................ 5 RO D A m

e n dm e n t

...................................................................................................................................... 6 R e m e d i a l D e s i g n

........................................................................................................................................ 7



### III. C o n st

ru cti o n A c

t i v iti e s

....................................................................................................... 8

I V

. C hr o n o l o g y o f E v en t

s

......................................................................................................... 8 Ma j or E v e n ts a n d S i g n i f i ca n t M il e s t o n e s

............................................................................................... 8 P ro j ec t e d A t t a i n m e n t o f C l ea n u p Go a l s

................................................................................................. 8



### V . Perf o rman c e S t andard s

........................................................................................................ 8 T ec h n o l o gy p e r f orm a n c e i n c om p a r i s o n t o c l e a n u p g o a l s, R es u l ts o f sa mp l i n g e ff or t

................... 8 P e r f orm a n ce D a t a Qu a li t y

........................................................................................................................ 9 O ve r s i g h t A c t i v i t i e s

................................................................................................................................... 9



### V I. F i na l In s pe c t i o n and C er

ti f i c a ti o n s

................................................................................ 10 R es u l ts o f I n s p ect i o n s

.............................................................................................................................. 10 I n st i t u t i o n a l Co n t ro l s

.............................................................................................................................. 10 Op e r at i o n a l a n d F u n ct i o n a l

................................................................................................................... 10



### V II. O pera

ti o n & Ma

i n t enan c e A c t i v iti e s

........................................................................... 11 Op e r at i o n a n d M a i n t e n a n ce A c t i v i t i e s

................................................................................................. 11 F u t ur e Gro u n d Wate

r R est or at i o n A c t i v i t i e s

....................................................................................... 11



### V III. Summar

y o f P r o j e ct C o s t

s

............................................................................................. 12 A ct u a l F i n a l Co st s

.................................................................................................................................... 12 P r ev i o u s Co st E s t i m at e

........................................................................................................................... 12 Comp a r i s o n

.............................................................................................................................................. 12 O ve r s i g h t Co s t s

........................................................................................................................................ 12I I



### I X

. O b s er v a ti o n s and Le ss o n s

Learne d

................................................................................ 12

X

. O perab l e U n it C o n t

a ct Inf o rma ti o n

................................................................................. 13

X I. R eferen c

e s

............................................................................................................................ 14

T ab l e s and F i g ure s

.................................................................................................................... 16 T ab l e 1: RO D

- Sp e

c i f i e d M CL s a

n d D r i n k i n g Wa t e r S ta n d a rd s, So l a Op t i c a l U S A

, I n c., So n om a Co u n ty, C A

............................................................................................................... 18 T ab l e 2: C h ro n o l o g y o f S i te ev e n ts, So l a Op t i ca l U S A , I n

c., S o n om a Co u n t y , C A

....................... 19 T ab l e 3: Gro u n d w ate r Q u a li ty D ata, P r

i m a r y V O C s ( 1997 t

o P r es e n t ) , F orm e r So l a Op t i ca l U

. S

. A

., I n c., F a

c i l i ty, P e t a l u m a, C a lif o r n i a

............................................................. 22 T ab l e 4: E P A O ve

r s i g h t Co sts

............................................................................................................... 28

F i g ur e 1: S i te V i c

i n i ty M a p , So l a Op t i c a l U S A

, I n c ., P et a l u m a, C a l i f or n i a

..................................... 29 F i g ur e 2: M o n i t or i n g W e ll Lo ca t i o n s , So l a Op t i c a l U S A

, I n c., P eta

l u m a , C a lif o r n i a

.................... 30 F i g ur e 3: Co n c e n t r a t i o n s o f 1,1

- DCE V e

r s u s T i m e i n W e ll W

- 2 7

..................................................... 31 F i g ur e 4: Co n c e n t r a t i o n s o f 1,1

- DC A V e

r s u s T i m e i n W e ll W

- 2 7

.................................................... 32II I 

## A CRON YM S

1,1,1

- T C A 1,1,1

- t

r i c h l oro et h a n e 1,1,1

- T C A 1,1,1

- t

r i c h l oro et h a n e 1,1,2

- T C A 1,1,2

- t r i c h l oro et h a n e 1,1

- DC E 1,1

- d i c

h l oro e t h e n e 1,2

- D C A 1,2

- d i c h l oro e t h a n e bgs be

l o w g rou n d s

ur f ac e CS P R M D Co

u n ty o f S o n om a P e r m i t a n d R es o ur ce Ma n ag e m e n t D e p a r t m e n t E P A U n

i te d S tates E n

v i ro n m e n ta l P ro tec t i o n A g e n c y G W TS g rou n d w ate r e x t r act i o n a n d t r eat m e n t sy s te m I C i n

s t i t u t i o n a l c o n t ro l M CL Ma

x i m u m Co n ta m i n a n t L i m i t μg / L m

i c ro g r a m s p e r li te r M NA mo

n i t or e d n at ur a l att e nu at i o n

m s l m

ea n se a l ev e l O & M op e

r at i o n a n d m a i n t e n a n c e O U op e

r ab l e u n i t P C E tet

r ac h l oro et h e n e pp b p a

r ts p e r b il l i o n R A O R e

m e d i a l A ct i o n O b j ec t i ve RO D R ec

ord o f D ec i s i o n T CE t

r i c h l oro e t h e n e t DCE t

r a n s

- 1 ,2

- d i c h l oro et h e n e T I tec

h n i c a l i mpr a ct i c a b i l i t y U ST u n d e

r g rou n d st

or age t a n k VO C v o

l at il e or ga n i c c ompo u n d1



## I

. I n t r o du ctio n

L o c a ti o n, si ze, en

v i r o nmen t a l s e t ti n g , l and and re s o ur

c e u s e

T h e So l a Op t i ca l U S A , I n

c. ( So l a ) S u p e r f u n d S i t e ( S i te ) i s l o cate

d i n t h e C i t y o f P e t a l u m a i n So n om a Co u n ty, C a l i f or n i a, j u st east o

f L ake v il l e H i g h w a y ’ s i n te r s e ct i o n wi t h I n te r state H i g h w a y 101, a s s h o w n o n F i g ur e 1. A do be Cr e e k li es 0. 3 m

il e w est o

f t h e S i te a n d fl o w s i n t o t h e P eta l u m a R i ve r o n e m il e f rom t h e S i t e. T h e S i te i s ess e

n t i a ll y fl at, a n d a m a n u f a ct ur i n g b u il d i n g a n d a d j o i n i n g a dm i n i st r at i o n o f fi ce b u i l d i n g o c c u p y t h e m a i n prop e r ty. S i x

u n d e r g rou n d st

or age t a n ks (U ST s ) w e r e f orm e r l y l o cate d b e h i n d t h e n or t h c or n e r o f t h e

m a n u f a ct ur i n g p a r t o f t h e f ac i li ty. T h e S i te b u il d i n g i s o cc u p i e d by t h r ee c omp a n i es, w h i c h

access t h e m a i n f a c ili t y b u il d i n g a n d t h e l o a d i n g do cks. T

h e r e i s a f e n c e l o cate d a l o n g t h e easte r n S i t e b o u n d a r y. S i n ce 2

0 05, a n as p h a l t p a r k i n g l o t a n d f o ur b u il d i n g p a d s wi t h t h e
ass o c i ate d be l o w g r a d e i nf r ast ru ct ur e ( i .e., e l ect r i ca l a n d p l u m b i n g ) h a ve bee n c o n st ru cte d o n t h e a ux il i a r y 11 ac r e l o t, a d j ac e n t t o t h e m a i n pr o p e r ty.

T h e t opo g r a p h y o f t h e a r ea, i n c l u d i n g t h e S i te, g e

n t l y s l op es 50 f

eet p e r m i l e f rom l o w h il l s i n t h e east t o w a rd s t h e P et a l u m a R i ve r , l o c a te d a ppro x i m ate l y o n e m il e s o u t h w e s t o f t h e So l a b u il d i n g. A d o be Cr eek, l o cate

d 0.3 m il e w est o

f t h e So l a b u il d i n g, ru n s n o r t h- s o u t h a n d fl o w s i n te rm i t te n t l y i n t o t h e P e ta l u m a R i ve r o n e m il e s o u t h f rom t h e S i te.

G e o l o g i c i n ve s t i ga t i o n s i n d i c a te t h at t h e d e po s i t i o n a l se d i m e n ts at t h e S i t e c o n s i st o f a c omp l e x
se q u e n ce o f a ll u v i a l d e p o s i ts c o n s i s t i n g o f i n te r b e dd e d c l ays, s il ts
, a n d s a n d s, w i t h l esse r
a mo u n ts o f g r a ve l

. A t d e p t h s o f a ppro x i m ate l y 8 0 t o 100 f e e t be l o w g rou n d s ur f ace ( bgs )

, t h i cke r c l ay i n te r v a l s a r e pr ese n t, w h i c h a pp ea r t o be r e l at i ve l y c o n t i n u o u s o ve r d i sta n ces o f h u n dr e d s o f f eet

. I n te r b e dd e d wi t h i n t h e c l ay a r e s il t, s a n d

, a n d g r av e l l a y e r s o f va r i o u s t h i c k n es s es. T h e se d ee p e r se d i m e n t s pro bab l y r e p r ese n t c omp l e x a ll u v i a l a n d est u a r i n e d e po s i t i o n a l e n v i r o n m e n ts ( L F R , 198

9 )

.

S i n ce O ct

o be r 20 0 5, g rou n d w a

t e r i n t h e s h a ll o w s e d i m e n t s i s g e n e r a l l y e n c o u n te r e d f rom 6 t o 18.5 f eet ab o ve m e a n s ea l eve l ( m s l )

. T h e a q u i f e r i s u n c o n f i n e d a n d t h e g r o u n d w ate r fl o w s
s o u t h / s o u t h w es t e r l y t o w a rd s t h e P e t a l u m a R i v e r , mo st li ke l y t h e p o i n t o f d i s c h a r ge. N at ur a l

r ec h a r ge o c c ur s at t h e b a se o f t h e f oo t h i ll s t o t h e n or t h / n or t h ea s t. T h e s h a l l o w a q u i f e r e x te n d s t o a ppro x i m ate l y 30 f eet be l o w m s l a n d h as be e n c l ass i fi e d by t h e U

. S

. E n v i ro n m e n ta l P ro tect i o n A ge n cy ( E P A ) as a C l as

s IIa dr i n k i n g w ate r s o ur ce a q u i f e r

. B e l o w t h e s h a ll o w
a q u if e r , t h e i n te rm e d i at e a q u i f e r i s a ppro x i m ate l y 30 t o 60 f eet b e l o w m s l

. T h e d ee p a q u if e r i s f rom a ppro x i m ate l y 60 t o 100 f eet be l o w m s l

, t h e d ee p e r a q u if e r f rom a p p rox i m ate l y 100 t o 2 00 f eet b e l o w m s l

, a n d t h e d ee p est a q u i f e r i s g r ea t e r t h a n 200 f eet b e l o w m s l ( L F R , 1990

)

.

T h e 35

- ac r e So l a prop e r t y i s z o n e d f or i n d u st

r i a l u se. L a n d

- u se i n t

h e s urr o u n d i n g a r ea i s i n d u st r i a l , c omm e r c i a l

, r es i d e n t i a l

, a n d u n d eve

l o p e d l a n d

. T h e a d j ac e n t p rop e r ty t o t h e w e st o f
t h e S i te w as pr

e v i o u s l y o w n e d by S te ro Comp a

n y , a m a n uf act ur e r o f d i s h w as h e r s. T h e r e a r e

r es i d e n t i a l s u b d i v i s i o n s t o t h e n or t h a n d n or t h w e st o f t h e S i te, a ppro x i m a t e l y 200 f eet a w ay. P rop e r ty east o f t h e S i te i s u se

d f or o f f i ce s p a ce a n d t h e H a r vest C h r i s t i a n S c h oo l

.2

A ppro x i m ate l y 11 pr e v i o u s l y u n d eve

l op e d ac r es ( 889,060 s

q u a r e f e e t ) i n t h e s o u t h w e st por t i o n
o f t h e S i te w e

r e p ur c h as e d by RN M C a

d e r , L

. L

. C

. ( RN M ) f

or d e v e l opm e n t

. An as p h a l t p a r k i n g l o t a n d f o ur b u il d i n g p a d s wi t h t h e ass o c i ate d b e l o w g r a d e i nf r a st ru ct ur e (i .e., e l ect r i ca l a n d p l u m b i n g ) w e r e c o n s t ru cte d o n t h i s l o t be t w e e n 2 005 a n d 2010. T

h e r e m a i n i n g 24 a c r es o f t h e So l a prop e r ty, i n c l u d i n g t h e b u i l d i n gs, w e r e s o l d t o Kl a n d

, L

. L

. C

. i n 2

002. B u il d i n

g s o n t h e S i t e f ac i li ty p a r c e l i n c l u d e t h e or i g i n a l m a n u f act ur i n g b u il d i n g, a n a d j o i n i n g a dm i n i st r at i o n o f fi ce b u il d i n g, a n d a p a r k i n g l o t s urr o u n d i n g t h e b u i l d i n gs. T h r ee c omm e r c i a l t e n a n ts c urr e n t l y
o cc u p y t h e S i te b u il d i n g : P eta l u m a P o u l t r y, R e y n o l d s P a ckag i n g, a n d S c o t t L ab or at or i es. P eta l u m a P o u l t r y c o n d u cts sa

l e s a n d d i st r i b u t i o n o f po u l t r y; R ey n o l d s P ac kag i n g c o n d u ct s st or age a n d d i st r i b u t i o n o f f ood p ac k ag i n g m ate r i a l s; a n d S c o tt L a b or at or i es c o n d u c t s

m a n u f a ct ur i n g a n d f i n i s h i n g o f c or k f or t h e w i n e i n d u st

r y

.

T h e C i ty o f P e t a l u m a u s e s t h e un c o n f i n e d a q u if e r i n t h e a r ea a s a dr i n k i n g w ate r s o ur ce. I n t h e

v i c i n i ty o f t h e S i te, o n e C i ty o f P eta l u m a m u n i c i p a l w ate r s u pp l y w e

l l ( S t a t i o n # 5, sc r e e n e d f rom 180 t o 5 1 2 f eet bgs ) a n d t w o pr i vate w e l l s ( S t e ro i n d u st

r i a l w e l l a n d C r a n d e ll r e s i d e n t i a l

w e l l ) w e r e pr e v i o u s l y u s e d . I n a d d i t i o n , o n e C i ty o f P et a l u m a w e ll ( sc r e e n e d f rom 60 t o 2 8 0 f eet bgs ) w as i n st a ll e d at t h e S i te b u t n e ve r u se d

. A ll o f t h e se w e ll s h ave bee

n s h u t do w n a n d / or aba n d o n e d i n a cc ord a n c e wi t h S tate o f C a l if or n i a w e ll d ec omm i s s i o n i n g r e q u i r e m e n ts

.


### O pera ti o na l H ist o r y and Wa st e Mana g eme n t Pra ct i c e s

So l a m a n uf act ur e d op h t h a l m i c l e n ses f rom 197 8 t h rou g h 200 1

. T h e f a c ili t y c o n s i ste d o f o n e

m a n u f a ct ur i n g b u il d i n g a n d a n a d j o i n i n g a dm i n i st r at i o n o f f i ce b u i l d i n g. T h e m a n u f act ur i n g pro cess i n

v o l ve d t h e i n j e ct i o n o f a c ata l yze d , t h e r mo sett i n g r es i n i n t o a c a v i ty be t w e e n po li s h e d g l ass mo l d s

. T h e m o l d a s se m b l y w as t h e n p l ace d i n a n a i r o v e n t o c ur e t h e r es i n

. T h e asse m b l y

w as r e mo ve d f rom t h e o ve n a n d s u bs e q u e n t l y p u t t h rou g h a c l e a n i n g pro c ess be f or e t h e prod u ct i o n w a s r e p eate d

. T h e s i x U ST s l o c a te d b e h i n d t h e r ea r n or t h c or n e r o f t h e

m a n u f a ct ur i n g p a r t o f t h e f ac i li ty w e r e u se d t o s t or e s o l ve n t s s u c h as 1,1 ,1

- t

r i c h l oro et h a n e ( 1,1, 1

- T C A ) , acet

o n e, a n d m et h a n o l

.



### R e g u l a t o r y and enf o r c emen t h ist o r y , S it e i n v e sti g a

ti o n a c t i v iti e s a nd ma j o r f i nd i n g s , Pr i o r rem ov a

l and r e med i a l a c t i v iti e s

.

I n May 1982, So

l a f o u n d l o w c o n c e n t r at i o n s o f v o l at il e or g a n i c c ompo u n d ( VO C ) c o n ta m i n a t i o n i n t h e g rou n d w ate

r b e n e at h t h e S i te, n ea

r t h e s i x U ST s. I n 1983, t h e S a n F r a n c i sc o R eg i o n a l Wate r Qu a li ty C o n t ro l B o a rd ( R eg i o

n a l Bo a rd ) d i r ecte d So l a t o i n ves t i gat e t h e c o n ta m i n a t i o n
a n d 1, 1

- D C A , 1, 1

- d i c

h l o r o et h e n e ( 1

, 1

- DC E )

, m

e t h y l e n e c h l or i d e, a n d 1,1, 1

- t

r i c h l oro e t h a n e ( 1,1, 1

- T C A ) w e

r e i d e n t i fi e d i n t h e g rou n d w ate

r

. I n J u l y 1 985, So

l a e x cava t e d a n d r e mo ve d t h e
s i x U ST s. W h e n t h e t a n k s w e r e r e mo ve d

, t h e r e w e r e n o s i g n s o f l eakag e f

r om t h e t a n ks; h o w e v e r , o bse r va t i o n s o f t h e t a n k f il l p i p es a

n d s urr o u n d i n g bac k f i ll s h o w e d sta i n i n g o n t h e p i p es a n d i n t h e a d j a c e n t back f ill ( L F R , 199

0 ) . It w as c

o n c l u d e d t h at t h e g r o u n d w ate r
c o n ta m i n a t i o n m i g h t be a r es u l t o f a c c i d e n ta l s p i l l age a d j ac e n t t o , or l ea ka ge f rom , t h e f i ll p i p es

.

T h e t a n k r e mo va l i n c l u d e d e x cavat i o n o f g r a ve l b ack f i ll m ate r i a l s a n d t h r e e t o fi ve f eet o f n at i ve
s o il f rom t h e s i d es a n d b o tt om o f t h e e x cava t i o n p i t. Co n fi rm at i o n sa m p l i n g i d e n t i fi e d t h e pr ese n ce o f t h r ee c o n t a m i n a n ts: a cet o n e, 1, 1

- DCE

, a

n d t r a n s

- 1 ,2

- d i c h l oro e t h e n e ( t DC E )

. B ase

d

o n t h ese f i n d i n gs , a n a d d i t i o n a l t w o f eet o f s o i l w as e x cavate d f rom t h e e a ste r n w a ll o f t h e3

f orm e r ta n k a r e a . F ur t h e r c o n f i rm at i o n sa mp l i n g d e mo n st r ate d t h e pr es e n ce o f VO C s, i n c

l u d i n g acet o n e

. N o a dd i t i o n a l e x cavat i o n w a s p e r f orm e d ( L F R , 199

0 )

.

I n J u l y 1986, s o

il gas sa m p l es w e r e c o ll e c te d f rom 40 l o ca

t i o n s, r a n g i n g f rom t h r ee t o fi ve f eet bgs, t o d ete rm i n e i f VO C s w e

r e m i g r a t i n g f rom s h a ll o w g ro u n d w ate r a n d t o a i d i n se l e ct i o n o f l o cat i o n s f or g rou n d w at

e r mo n i t or i n g a n d e x t r act i o n w e ll s. C h e m i ca l s d et e cte d i n t h e s o il g as i n c l u d e d : c h l oro f orm , c a r b o n tet r a c h l or i d e , 1,1

- D C A , 1, 1

- DCE , tet r a c h l or o et h e n e ( P CE )

, a

n d 1,1,1

- T C A . Ma

x i m u m c o n c e n t r at i o n s w e r e f o u n d a ppro x i m ate l y 70 f eet d o w n g r a d i e n t f rom t h e l o cat i o n o f t h e f orm e r U S T s ( C H 2 M H il l , 199 1 )

.

I n 198 7 , t h e R eg i o n a l Bo a rd ord e r e d So l a t o c o n st r u ct a n d op e r ate a g rou n d w ate r e x t r act i o n a n d
t r eat m e n t s y ste m ( G W TS )

. So l a c o n d u cte d t h e a ct i v i t i es, wi t h t h e t r eate d g r o u n d w ate r b e i n g d i sc h a r ge d i n t o A d o be C r eek, j u st n or

t h w est o f t h e S i te, u n d e

r a p e rm i t f r o m t h e R eg i o n a l Bo a rd

. T h e e x t r act i o n a n d t r eat m e n t s y ste m beg a n op e r at i n g i n 198 8

. So l a a l s o a rr a n ge d t o h a ve t h e C i ty o f P eta l u m a s h u t do w n t h e n ea r by m u n i c i p a l w a te r s u pp l y w e

ll

, t o av o i d i n te r f e r e n ce wi t h t h e g rou n d w a

te r c l ea n- u p e ff or ts a n d pr ev e n t po t e n t i a l u s e o f S i t e

- i mp acte d g rou n d w ate

r

.

I n 198 9

, E P A b e ca m e t h e l ea d r eg u l at or y ag e n cy f or r e m e d i a l ac t i v i t i es at t h e S i te. O n

Feb ru a r y 21, 1990, E P

A a dd e d t h e S i te t o t h e N at i o n a l P r i o r i t i es L i st o f S u p e r f u n d s i t es. Soo n t h e r ea f t e r , E PA i ss u e d a n a dm i n i s t r at i ve ord e r d i r ec t i n g So l a t o c o n d u c t f ur t h e r e n v i ro n m e n t a l sa mp l i n g

a n d t o pr e p a r e a r e m e d i a l i n vest i g a t i o n r e por t a n d a f ea s i b i l i ty st u d y o f c l ea n- u p op t i o n s, b o t h

o f w h i c h So l a c omp l ete d i n 1 9 91

.

B ase d o n t h e r e m e d i a l i n vest i gat i o n r e por t, f e as i b ili ty st u d y, a n d r i s k asse s s m e n t, E P A i ss u e d
t h e or i g i n a l R ec ord o f D e c i s i o n ( RO D ) o

n S e p te m be r 27, 1991

. T

h e RO D d ete

rm i n e d t h at a n
e x p a n d e d G W TS w as t h e mo st a ppropr i ate m e t h od f or r e m e d i at i n g c o n t a m i n a t i o n a t t h e S i te.

So l a e x p a n d e d t h e syst e m i n 1 992 p ur

s u a n t t o E P A’ s RO D

, a

n d c o n t i n u e d op e r at i o n s. T h e syste m w a s e x p ecte d t o r est or e t h e s h a l l o w g rou n d w ate r t o c l ea n

- u p st a n d a rd s wi t h i n 1 5

- 20 yea r s. I n i t i a l l y, c o n c e n t r at i o n s o f t h e VO C c

o n t a m i n a t i o n a t t h e S i te d ec

r ease d s i g n i f i c a n t l y

. B y 1997, h o w eve r , t h e r ate o f c o n ta m i n a n t r e d u ct i o n s l o w e d t o a l mo st ze ro

. G rou n d w ate

r
mo n i t or i n g d ata at f

o ur w e ll s s h o w e d t h at c o n c e n t r at i o n s o f t w o c o n ta m i n a n ts, 1, 1

- DCE a

n d 1,1,

- D C A , a

pp ea r e d t o h ave sta b ili ze d a n d r e a c h e d a n asy mp t o t e at l e ve l s ab o ve t h e c l e a n

- u p sta n d a rd s. C o n t i n u e d m o n i t or i n g r e f l ecte d n o f u r t h e r r e d u ct i o n s i n c o n t a m i n a n t c o n c e n t r at i o n s. Som e p a r ts o f t h e c o n t a m i n ate d a q u i f e r h a d a c h i eve d t h e c l e a n- u p st a n d a rd o f 5 p a r ts p e r b il l i o n ( pp b ) f or 1, 1

- DC A by t

h i s t i m e, b u t s om e p a r ts h a d n o t. T h e e x t r ac t i o n a n d t r eat m e n t syste m w a s n o l o n ge r e f f ect i ve l y r e mo v i n g t h ese l o w e r c o n ce n t r at i o n s o f c o n ta m i n a n ts f rom t h e g rou n d w ate

r

.

I n 199 7

, So l a r e q u este d a ppro va l f rom E P A t o s h u t o ff t h e e x t r ac t i o n a n d t r eat m e n t s y ste m a n d i ss u e a te c h n i c a l i mpr ac t i cab i l i ty ( T I ) w a i ve r , a r g u i n g t h at t h e c l e a n- u p g o a l s f or t h ese t w o
c o n ta m i n a n ts c o u l d n o t be a c h i eve d u s i n g e x t r a c t i o n a n d t r eat m e n t. E PA r e q u este d i n stea d
t h at So l a e x a m i n e mo n i t or e d n at ur a l att e n u at i o n ( M NA ) as a po

t e n t i a l r e m e d y f or t h e S i te. So

l a
cease d op e r at i n g t h e g r o u n d w ate r e x t r ac t i o n a n d t r eat m e n t s y ste m a n d m o n i t or e d t h e a q u if e r ’ s

r es po n se u n d e r E P A ’ s o

v e r s i g h t.4

T h e c o n c e n t r at i o n s o f t h e t w o r e m a i n i n g c o n ta m i n a n ts s l o wl y d e c l i n e d

. I n 2001

, So l a a n a l yz e d
t h e d ata g

at h e r e d s i n ce s yste m s h u t

- do w n i n 19 97 a n d pr es e n te d i t s eva l u a t i o n o f M N A

, f o ll o w i n g E P A g u i d a n ce

. So l a c o n c l u d e d t h at e x t r act i o n a n d t r ea t m e n t a l o n e w o u l d n o t b e
ca p ab l e o f a c h i e v i n g t h e c l e a n- u p st a n d a rd f or t h e r e m a i n i n g a q u i f e r c o n t a m i n a n t. S o l a ’ s
eva l u at i o n c o n c l u d e d t h at M N A w o

u l d l i ke l y be a n e f f ec t i ve r e m e d y f or a tta i n i n g t h e c l e a n- u p sta n d a rd

. T h e e x t r act i o n a n d t r eat m e n t sy s te m w as d ec

omm i s s i o n e d i n 2 0 02.

S i n ce 2 002, So l a c o n t i n u e d se m i- a n n u a l m o n i t or i n g. R es u l ts h a ve s h o w n t h at c o n ce n t r a t i o n s o f
t h e t w o c o n ta m i n a n ts c o n t i n u e d t o d ec l i n e. I n 2 0 07 E P A f orm a ll y s e l ecte d M N A as t

h e s i te

r e m e d y i n a R e c ord o f D ec i s i o n

.


### O perab l e U n i t

s D e s i g na

t ed, O perab l e U n i t A pp lic ab l e t o t h is R A R ep o r

t

T h e r e w as o n l y o n e op e r ab l e un i t ( O U) d es

i g n at e d f or t h i s s i te

.5



## II

. Op e r a b l e U n it B a

c k g r o und

R equ i remen ts S pe ci f

i ed i n t he R O D f

o r t he O U

T h e RO D f

or t h e S i te w a

s s i g n e d o n S e p te m be r 2 7, 1991 ( E P

A , 1 9 91 )

. T h e R e m e d i a l A ct i o n O b j ec t i ve ( R A O ) w as t

o r est or e g rou n d w ate

r t o i t s be n e fi c i a l u se, w h i c h i s dr i n k i n g w ate r

. T h e
se l ecte d s i te c l ea n u p r e m e d y c o n s i ste d o f t h e f o ll o w i n g e l e m e n ts:

n Gro u n d w ate r m o n i t or i n g t o ass ur e ca p t ur e o f c o n ta m i n ate d g rou n d w ate

r a n d t o d e mo n st r ate r est or a t i o n o f g rou n d w a

t e r t o c l e a nu p sta n d a rd s t h rou g h o u t t h e a q u if e r

n Op e r at i o n o f e x i st i n g e x t r act i o n w e l l s ( 8 )

n Co n st ru ct i o n a n d op e r at i o n o f t w o a dd i t i o n a l s h a l l o w e x t r act i o n w e l l s

n Co n ve r s i o n o f m o n i t or i n g w e l l s L F

- 13 a

n d L F

- 17 t

o d ee p e x t r act i o n w e l l s

n Co n st ru ct i o n a n d op e r at i o n o f a d d i t i o n a l p i p i n g f or t h e n e w a n d c o n ve r t e d w e l l s

n O n- s i te t r eat m e n t a n d d i sc h a r ge o f f

- s i te or d i s c

h a r ge t o t h e C i t y o f P eta l u m a se w age t r eat m e n t s y ste m

T h e e n h a n ce d G W TS

, w h i c h be g a n op e r a t i n g i n 1992, w as e

x p ecte d t o r e s t or e t h e s h a l l o w g rou n d w ate

r t o c l e a n- u p sta n d a rd s i n 15 t

o 20 y ea r s. T h e syste m ’ s d ee p e x t r act i o n w e l l s w e r e

n ee d e d t o pr ev e n t f ur t h e r m i g r at i o n o f c o n ta m i n a n ts i n t o t h e d ee p e r por t i o n o f t h e a q u i f e r

. T h e

r e m e d y i n c l u d e d c o n st ru ct i n g a ca r b o n f il t r a t i o n s yste m at t h e f a c i l i ty t o t r eat t h e e x t r a c te d g rou n d w ate

r , a n d d i s c h a r g i n g t h e t r eate d w ate r o ff

- s i te t o A do be Cr eek ( E PA

, 199 1 )

. T

h e g rou n d w ate

r c l ea n u p s ta n d a rd s w e r e set at s t ate or f e d e r a ll y prom u l gat e d dr i n k i n g w ate r sta n d a rd s, k n o w n a s M a x i m u m Co n ta m i n a n t L e v e l s ( M C L s )

. T h e a pp l i ca b l e dr i n k i n g w ate r sta n d a rd s a n d t h e M CL s li ste

d i n t h e RO D a

r e s h o w n i n T a b l e 1

.

I n 199 7 , t h e G W TS w a s t ur n e d o ff beca u se i t w a s n o l o n ge r e f f ect i ve l y r e d u c i n g c o n ta m i n a n t

c o n c e n t r at i o n s. W i t h o u t t h e G W TS op e r at i n g, c o n ta m i n a n t c o n ce n t r a t i o n s s l o wl y c o n t i n u e d t o d ec r ease. So l a be li e ve d n at ur a l att e n u at i o n w as ca u s i n g t h i s d ec r ease , a n d t h ey be g a n t o st u d y t h e p h e n om e n a. A f te r t w o yea r s, t h e G W TS w as d ec

omm i ss i o n e d a n d a n u m be r o f t h e
mo n i t or i n g w e ll s a n d p i e z om ete r s w e r e d ec o m m i ss i o n e d

. B ase d o n t h e g rou n d w ate

r
mo n i t or i n g d ata d ur

i n g t h i s t i m e, So l a r e q u este d t h at E PA c

o n s i d e r M N A as a f

i n a l r e m e d y ( L F R , 200 1 )

. T

h e fi r st fi v e yea

r r ev i e w f or t h e S i t e w as c o n d u cte d i n 2 000 a n d i n d i c a te d t h at t h e RO D r e m e d i a l ac t i o n o b j ect i ves o f pr ev e n t i n g m i g r at i o n o f c o n ta m i n ate d g rou n d w ate

r a n d

r est or i n g t h e a q u if e r c o n t i n u e d t o b e m et, ev e n t h o u g h t h e G W TS w as n o l o

n ge r op e r at i n g, a n d
t h e P R P w as st

u d y i n g t h e n at ur a l a t te n u a t i o n be l i eve d r es po n s i b l e f or t h e c o n t i n u e d

c o n ta m i n a n t d e c r ease.



### B a sis f o r Cl eanup G o a

l s

A l t h o u g h t h e i n te r i m r e m e d i a l a ct i o n s i n t h e 19 8 0 ’ s

– i n te r i m p u mp i n

g a n d t r eat m e n t o f g rou n d w ate

r , a n d r e mo v a l o f t a n ks a n d c o n ta m i n ate d s o il

– r e d u ce d S i te r i sks, g rou n d w ate

r be n ea t h t h e S i te st i l l e x c e e d e d dr i n k i n g w ate r st a n d a rd s, r e d u c i n g i ts f u l l b e n e f i c i a l u se as dr i n k i n g w ate r

. T w e l ve c h e m i c a l s o f po te n t i a l c o n ce r n w e r e i d e n t i f i e d i n t h e 1991 RO D : acet o n e , b u ta n o n e, 1 ,1

- D C A , 1, 2

- d i c h l oro e t h a n e ( 1,2

- D C A)

, 1 ,1

- DCE , F r

e o n 113, 4

- m e t h y l

- 2- p e n t a n o n e, P CE , t

o l u e n e , 1,1,1

- T C A , 1,1

, 2

- t r i c h l o r o et h a n e ( 1

, 1,2

- T C A)

, a n d t r i c h l oro et h e n e ( T CE )

. C o

n ta m i n at i o n w as f o u n d i n t h e s o il ( ace t o n e r a n g i n g u p t o 5 4 m g / kg a n d 1,1

- DCE at 0.051 m g / k g )

, a n d i n t h e g rou n d w ate

r ( pr i m a r il y 1,1

- D C A , 1, 1

- DCE , 1,1

, 1

- T C A , a n d F r e o n

- 113 )

.6

T h e h i g h e s t c o n ta m i n a n t c o n c e n t r a t i o n i n g rou n d w ate

r w a s 1, 1

- DCE ( 3

, 3 0 0 m i c ro g r a m s p e r li te r [ μ g / L ] ) d ete

c te d i n s h a l l o w w e l l W

- 1 4 l o c a t e d do w n g r a d i e n t o f t h e f o rm e r U ST a r ea. T h e

w e ll s o n t h e d o w n g r a d i e n t e d ge o f t h e S i te i n d i c

a te d t h at t h e l ate r a l e x t e n t o f t h e VO C

c o n ta m i n a t i o n wi t h i n t h e So l a prop e r ty w as at o

r be l o w t h e c l e a n- u p st a n d a rd s ( E P A , 1 9 91 )

.

T h e r i sk as s ess m e n t pr e s e n te d i n t h e RO D i n d i c

a t e d a n e x ce s s l i f et i m e c a n ce r r i sk base d o n u se
o f o n

- s i te c o n t a m i n ate d g rou n d w ate

r f or dr i n k i n g w ate r o f 1 x 10

- 4 ( 1 p e r s o n o u t o f 10

, 000 p e op l e )

, pr i m a r i l y f rom 1,1 DCE

. T

h e n o n- c a r c i n o ge n i c r i sk est i m ate f or c o n ta m i n ate d g rou n d w ate

r i n d i c ate d t h at n o a d ve r se n o n ca r c i n o ge n i c h e a l t h e f f ects w e r e e x p ecte d

.

T h e ec o l o g i ca l assess m e n t i d e n t i fi e d A do be Cr e e k as t h e c l o ses t s ur f ace w ate r b od y t o t h e S i te

a n d as a s i te o f a l o ca l p r o j ect t o r e i n t rodu ce a n a d romou s stee

l h ea d t rou t t o t h e c r eek. H o w eve r , w ate r q u a li ty s a mp l es f rom g rou n d w ate

r m o n i t o r i n g w e ll s i n s ta ll e d be t w ee n t h e So l a prop e r ty

a n d A do be Cr eek d i d n o

t d etect a n y c o n ta m i n a n t s, i n d i cat i n g t h at d i s c h a r ge o f c o n ta m i n a n ts t o
s ur f ace w a te r h a d n o t o c c urr e d . I n a dd i t i o n , c o n t a m i n a n ts d e tecte d i n g r o u n d w ate r at t h e S i te

w e r e be l o w t h e i r c orr es p o n d i n g f e d e r a l s ur f ace w ate r q u a li t y c r i te r i a f or t h e pro tect i o n o f

a q u at i c l i f e

.


### ROD A mendmen t

E PA w or

ke d w i t h So l a o n ev a l u at i n g t h e g ro u n d w ate r r e m e d i a t i o n a f te r t h e G W TS w as s h u tdo w n i n 1 997. So

l a pr e p a r e d a r e por t eva l u at i n g M o n i t or e d N at ur a l A tt e nu at i o n ( M NA ) i n 2001, a n d E P A i n d i cate

d i t w o u l d pro cee

d wi t h a m e n d i n g t h e RO D t

o es t ab li s h M N A as t

h e

n e w r e m e d y

. I n 2002, So

l a d e mo li s h e d t h e G W TS a n d pr e p a r e d a w or k p l a n a n d mo n i t or i n g

r e por t f or M N A

. D u e t

o l o w s i te r i sks a n d h i g h e r e n v i r o n m e n ta l pr i or i t i es , E PA d i d n o

t pro cee d wi t h t h e r e m e d y d ec i s i o n pro cess un

t il 2 005. I n 2 006, E P A pr e p a r e d a P ropo

se d P l a n ( i ss u e d i n J a n u a r y 2 0 07 ) f or t h e M N A r e m e d y. I n Ma r c h 2 007, E P A s i g n e d t h e R O D A m

e n dm e n t t h at

se l ecte d M N A a

n d i n s t i t u t i o n a l c o n t ro l s ( I C s ) t o ac h i eve a n d s u sta i n c l e a n- u p st a n d a rd s at t h e S i te.

So l a beg a n i mp l e m e n t i n g t h e M N A m

o n i t or i n g i n 2003

, u po n E P A a ppr o va l , c o n s i s t i n g o f se mia nn u a l sa mp l i n g. T h ey c o n t i n u e d t h e se m i

- a n n u a l sa mp l i n g t h rou g h D e

c e m be r 2009. O n e g rou n d w ate

r m o n i t or i n g eve n t w as c o n d u cte d i n 2010 a

n d n o n e i n 2 0 11. E PA i s e

n gag i n g w i t h So l a t o r es u m e t h e m o n i t or i n g pro g r a m

.

I n J u l y 2007, E P

A a ppro v e d So l a ’ s propo

sa l t o ab a n do n t h r ee g rou n d w ate

r mo n i t or i n g w e ll s ( W

- 2 2, W

- 25, a n d L F

- 2 ) a n d t h r e e e x t r act i o n w e ll s ( E

- 3, E

- 5, a

n d E

- 7 ) t h at w e r e n o t n ee d e d f or t h e M N A mo

n i t or i n g p l a n

. I n acc ord a n ce wi t h t h e 2007 RO D A m

e n dm e n t, n o a dd i t i o n a l w e ll s h ave b ee n i n s ta ll e d o n t h e S i te.

I C s w e r e a l s o a c omp o n e n t o f t h e RO D A m

e n dm e n t. I C s a r e n o n- e n g i n ee r i n g m e t h od s by

w h i c h acc e ss t o c o n ta m i n ate d e n v i r o n m e n ta l m e d i a i s r est r i cte d

. T h e 19 9 1 RO D d i d n o

t i n c l u d e I C s as p a r t o f t h e r e m e d y ( E P A , 1 9 91 ) o n t h e ba s i s t h at g rou n d w ate

r at t h e S i te w o

u l d s o o n be

c l e a n e d u p t o f e d e r a l a n d state g rou n d w ate

r st a n d a rd s, r e n d e r i n g i t a va i l ab l e f or dom e s t i c u ses

.

T h e 2005 S e

c o n d F i ve

- Y e a r R ev i e w r e por t d ete r m i n e d t h at I C s s h o u l d be i mp l e

m e n te d ( E PA

, 2005a )

. A c c ord i n g l y, t h e 2007 RO D A m

e n dm e n t i n c l u d e d I C s t o pro tect a g a i n st i n a ppropr i ate7

u se o f t h e c o n t a m i n ate d g rou n d w ate

r u n t il t h e cl ea n- u p st a n d a rd s w e r e a c h i e ve d

. T h e I C ’ s i n c l u d e d a r est r i c t i ve c o v e n a n t a n d t h e l o c a l w e ll p e rm i tt i n g pro c e ss. Th e r est r i ct i ve c o v e n a n t

w as n eve

r i mp l e m e n t e d

. T h e w e ll p e rm i t t i n g I C c o n s i ste d o f h av i n g t h e C o u n ty o f So n o m a P e rm i t a n d R es o ur ce M a n age m e n t D e p a r t m e n t ( CS P R M D ) p l ace a n o t i fi c at i o n i n t h e i r
c omp u te r i ze d syste m ca l l e d P e rm i t s P l u s, r ega rd i n g t h e S u p e r f u n d s i te. T h i s i n s t i t u t i o n a l

c o n t ro l w as n o t i n i t i a ll y i mp l e m e n te d

, b u t as a r e s u l t o f t h e 2010 F i ve

- Y e a r R ev i e w i t h a s
s u bse q u e n t l y be e n p u t i n p l ace.



### R emed i a

l D e si g n

So l a h a d s u b m i tte d a w o r k p l a n f or i mp l e m e n t i n g M N A b a

ck i n 20 0 2, c o n s i st i n g o f c o n t i n u e d

se m i- a n n u a l g rou n d w at

e r mo n i t or i n g. M o n i t or i n g w o u l d c o n s i st o f w ate r l eve l m e a s ur e m e n ts f or 4 w e l l s a n d w ate r q u a li ty sa m p l i n g f or 1 w e l l ( W

- 2 7 )

. ( S ee f i g ur e 2 )

. E PA a ppro ve d t h i s propo sa l as t h e r e m e d i a l d es i g n ( E P A

, 2 008 )

. I n Ju l y 2007, t

h r ee g rou n d w ate

r mo n i t or i n g w e l l s ( W

- 2 2, W

- 25, a n d L F

- 2 ) t h at w e r e n o l o n ge r u se d a n d t h r ee e x t r act i o n w e l l s ( E

- 3, E

- 5, a

n d E

- 7 )

w e r e ab a n do n e d . I n acc o rd a n ce wi t h t h e 2007 R O D A m

e n dm e n t, n o a dd i t i o n a l w e l l s w e r e i n st a ll e d

.8



## I I I

. C o n st

r u ctio n Activit

i e s

N o a dd i t i o n a l f ac i li t i e s w e r e c o n st ru cte d f or t h e i mp l e m e n tat i o n o f t h e R OD A m

e n dm e n t

. Op e r at i o n a n d m a i n t e n a n ce ( O & M ) f

or t h e M N A r

e m e d y h as c o n s i ste d o f c o n d u ct i n g se mia nn u a l sa mp l i n g o f w at e r l eve l s a n d q u a li ty. S i n c e 2005, L F R / A r

ca d i s h a v e c o n d u cte d g rou n d w ate

r m o n i t or i n g eve n ts o n a se m i

- a n n u a l a n d a nn u a l ba s i s o n b e h a lf o f So l a.



## I V

. Ch r o n ology o f E v e n ts

Ma j o r E v en ts

and S i g n i f

ic an t M il e s t

o ne s

T ab l e 2 pro v i d es a c h ro n o l o gy o f ev e n ts a t t h e S i t e.



### Pr o j e ct ed A tt a i nmen t o f Cl eanup G o a l s

B ase d o n d a t a ga t h e r e d t h rou g h 201 0

, i t i s pro j ec t e d t h at t h e g rou n d w ate

r w o u l d by n o

w h ave atta i n e d c l e a n u p g o a l s

. ( S ee T ab

l e 3, F i g ur es 2 a n d 4 )

. A dd i t i o n a l sa mp l i n g i s n ee d e d t o c o nf i rm

w h e t h e r c l e a n u p g o a l s h ave be e n att a i n e d a n d m a i n t a i n e d

. E P A i s w or k i n g wi t h t h e P R P t o
a rr a n ge t h e c o nf i rm at or y sa mp l i n g

.



## V

. P erf o r m a n c e S t a nd ar d s

T e c hn o l ogy perf o r m a n c e i n c o mpar i s o n t o c l eanup go a

ls

, R e s u lts o f s amp li n g eff o r t

S h a ll o w w e ll s a r e t h o s e s c r ee n e d wi t h i n t h e a ppro x i m ate i n te r va l o f 0 t o 3 0 f eet bgs ( L F R , 19

9 0 )

. Co n st i t u e n ts d et e cte d i n t h e s h a l l o w a q u i f e r s i n c e 2005 i n c l u d e 1 ,1 D C A

, a

n d 1,1, 1

- T C A

. T ab

l e 3

s h o w s t h e m a x i m u m c o n ce n t r a t i o n s o f 1, 1

- DCE

, 1 ,1

- DC A , a

n d 1,1, 1

- T C A d etecte

d i n g rou n d w ate

r sa mp l es f r om t h e se v e n s h a ll o w w e ll s ( W

- 2 2 , W

- 25, W

- 27, L F

- 2, E

- 3

, E

- 5, a n d E

- 7 ) f rom 2005 t o 2 010. ( L F R / A r

ca d i s , 2009 a

n d R o t h

, 2010 )

. T h e c o n c e n t r at i o n s o f a l l t h r ee
c h e m i ca l s i n mo st w e ll s h a d s h o w n a dr a m a t i c d ec l i n e f rom h i g h i n i t i a l c o n c e n t r at i o n s i n 19 8 6 t o l o w c o n c e n t r at i o n s or n o n

- d etect by 20

0 5 a n d l ate r . I n w e ll W

- 2 7, c o n c e n t r at i o n s o f 1,1

- DCE

, 1,1

- D C A

, a

n d 1,1, 1

- T C A w e

r e n o n- d e t ect i n 1 9 86 a n d ro se l a te r

. T h e i r c o n c e n t r at i o n s f l u ct u ate d

u n t il A pr il 1 991, w h e

n 1

, 1

- DC A sta

r te d t o st e a d i l y i n c r e a se a n d r e m a i n e d ab o ve t h e M CL t h rou g h 20 0 9, e x ce p t f or a n o c c as i o n a l d i p i n c o n c e n t r at i o n

. A s o f 2009, o n l y o n e w e ll ( W

- 27 ) i n t h e s h a l l o w a q u i f e r w as st ill m o n i t or e d f or VO C s. T

h e 1, 1

- DCE c

o n c e n t r a t i o n s o ve r t i m e i n W27 a r e s h o w n i n F i g ur e 2

, a n d t h e 1, 1

- D C A c

o n c e n t r at i o n s o v e r t i m e i n t h e sa m e w e ll a r e s h o w n i n F i g ur e 4.

T h e c o n c e n t r at i o n o f 1

, 1

- DC A i n w e

ll W

- 27 h a d d ropp e

d be l o w t h e M CL o

f 5 μg / L i n

t h e J u n e 2010 sa mp l i n g, a l t h o u g h i t w i ll b e

sa mp l e d i n 20 1 2 t

o c o n fi rm t h e t r e n d

. S i n ce 2005, t

h e 1

, 1- DCE c o n c e n t r a t i o n h a d b ee n b e l o w t h e M CL ( 6 μ

g / L ) i n a ll l o cat i o n s

.

S i n ce 2 005, 1

, 1,1

- T C A h a

s n o t be e n d et e cte d i n g r o u n d w ate r sa m p l es c o ll e cte d f rom a n y o f t h e
s h a l l o w w e l l s o n t h e S i t e

.9

Gro u n d w ate r w as c o n t i nu o u s l y a n a l y z e d a n d d a t a r e por te d f or 1,2

- D C A

, T CE , a

n d F r e o n 113, b u t mo st o f t e n t h ese c o n st i t u e n ts w e r e n o n

- d ete c t i n a ll o f t h e w e l l s. S i n c e 2005, 1, 2

- D C A

, T CE

, a n d F r e o n 113 h ave n o

t b ee n d ete c te d i n a n y o f t h e g rou n d w ate

r sa m p l es c o ll ecte d f rom
s h a l l o w w e l l s o n t h e S i t e

. N o e m e r g i n g c o n s t i t u e n ts o f c o n ce r n ( COC s ) h a ve bee n i d e n t i fi e d i n
s o il or s o il g as at t h e S i t e ( E P A , 20 0 5a )

.


### Perf o rman c e D a t a Q u a lit y

To pro v i d e q u a li t y c o n t ro l f or t h e se m i

- a n n u a l g r o u n d w ate r m o n i t or i n g, t h e M N A W

or k P l a n
s p ec i f i e d t h at o n e fi e l d b l a n k a n d o n e d u p li cat

e s a mp l e w o u l d b e tak e n d ur i n g ea c h s a mp l i n g

eve n t ( L F R , 200

2 )

. T h e d u p li cate sa

m p l es w e r e t a ke n a n d t h e i r r es u l ts r e p or te d o n l y o n ce d ur i n g t h e t w o s a mp l i n g eve n ts i n 2003, t

w i ce a n n u a ll y d ur i n g 200 4 a n d 2 005, o n l y o n ce i n 200 6

a n d n o t i m es s i n ce t h e n

. N o d ata va

li d at i o n r e por t i n g w as m a d e

.


### O v er si g h t A cti v i ti e s

E PA o ve r s i g h t o f t h e M N A act

i v i t i es h as c o n s i s t e d o f r ev i e w i n g t h e se m i

- a n n u a l g rou n d w ate

r
mo n i t or i n g r es u l ts, as r e por te d by So l a ’ s c o n t r a c t or , a n d c o n d u ct i n g 5

- ye a r r ev i e w s. Gro u n d w ate r m o n i t or i n g r e por ts w e r e s u b m i tte d i n 2 0 03, 20 0 5, 2006

, 2007

, 2008, 20 0 9 a n d 2010. A 5

- y ea r r ev i e w w a s c o n d u cte d i n 2000, 2

0 05 a n d o n e i n 201 0

.1 0



## V I

. Fi n a l I n s p e ct io n a nd C er ti f ic a tio n s

R e s u l t s o f In s pe c

t i o n s

N o a dd i t i o n a l c o n st ru ct i o n ac t i v i t i es o cc urr e d t o i mp l e m e n t t h e r e m e d i a l a ct i v i t i es s e l ecte d by
t h e 20 0 7 RO D A m

e n dm e n t.



### In stit u ti o na l C o n t r o l s

A ct i o n s w e r e tak e n p ur s u a n t t o t h e 2007 RO D A m

e n dm e n t t o i m p l e m e n t o n e o f t h e t w o i n s t i t u t i o n a l c o n t ro l s s e l e cte d , t h e r est r i c t i o n s wi t h i n t h e Co u n ty o f So n o m a ’ s w e ll p e rm i tt i n g pro cess. So

n om a Co u n t y ’ s P e r m i t a n d R es o ur ce Ma n age m e n t D e p a r t m e n t ( CS P R M D ) i s

r es po n s i b l e f or i ss u i n g a l l w e l l i n sta l l at i o n p e rm i t s ( E P A

, 2 007 b )

. T h e C S PR M D h as a
c omp u te r i ze d syste m ca l l e d P e rm i t s P l u s t h at i s u se d t o m a i n ta i n i nf orm a t i o n ab o u t prop e r t i es i n S o n om a Co u n ty ( E P A

, 2007b )

. A s d esc

r i be d i n t h e 200 7 RO D A m

e n dm e n t, E PA r e q u este d
t h at t h e C S P R M D p l ac

e a n o t i fi ca t i o n wi t h i n t h e P e rm i ts P l u s syste

m r ega r d i n g t h e S i te p a

r ce l
t h at l i es d i r

e ct l y a b o ve t h e c o n ta m i n ate d g rou n d w ate

r

. Th i s n o t i ce w o u l d i n d i cate t

h at t h e p a r ce l i s p a r t o f a S u p e r fu n d s i te a n d t h at w e l l p e rm i ts s h o u l d n o t b e i ss u e d be f or e c o n s u l t i n g wi t h t h e CS P R M D a

n d E PA

. I f a

n y o n e r e q u est s a p e rm i t f or t h e So l a S i te p a

r ce l

, t h i s n o t i c e

w o u l d a pp ea r w i t h i n t h e P e rm i ts P l u s s y ste m a n d t h e C S P R M D w o

u l d r e v i e w t h e p e rm i t

r e q u est w i t h i n t h e c o n t e x t o f t h e S i te r e q u i r e m e n ts.

D ur i n g t h e 2010 5

- Y ea r R ev i e w , E P A l ea r n e d t h at t h e P e rm i ts P l u s sys

t e m d i d n o t c o n t a i n a n y
n o t i ce t h a t t h e S i te p a

r c e l li es d i r e ct l y a b o ve t h e c o n ta m i n ate d g rou n d w ate

r a n d t h at w e ll s
s h o u l d n o t be c o n st ru ct e d o n t h e prop e r ty. A l t h o u g h n o a d d i t i o n a l w e l l s h a d be e n i n st a ll e d o n t h e S i te s i n ce t h e pr ev i o u s 5

- Y ea r R ev i e w , t h e Co u n ty o f S o n om a w e ll p e r m i tt i n g r est r i c t i o n I C h a d n o t be e n i mp l e m e n t e d

. A s a r e s u l t o f t h i s f i n d i n g, E P A c o n tacte d t h e Co u n ty a n d h a d t h e m p l ace a n o

t i c e i n t h e i r p e rm i tt i n g d ata b ase r ega rd i n g t h e g rou n d w a

te r at t h e So l a Op t i c a l S u p e r f u n d S i te.



### O pera ti o na l and F un c

ti o na l

E PA d e te rm i n e d t h at t h e M N A r e m e d y w as op e

r at i o n a l a n d f un ct i o n a l w h e n E P A a ppro ve d
t h e r e m e d i a l d es i g n f or t h e M N A r

e m e d y o n Feb r u a r y 2, 2008 ( E P

A , 200 8 )

.1 1



## V II

. Ope r

a tio n & M a

i n t e n a n c e Acti v iti e s

O pera ti o n and Ma

i n t e nan c e A cti v i ti e s

T h e O & M ac

t i v i t i es ass o c i ate d wi t h t h e M NA r e m e d y c o n s i sts o f se m i

- a n n u a l g rou n d w ate

r
mo n i t or i n g. I n 20 0 5, 20 0 6, a n d ea r l y 2007, te

n w e l l s w e r e m o n i t or e d f or g rou n d w ate

r e l evat i o n
se m i- a n n u a ll y, s e ve n w e ll s w e r e sa mp l e d f or VO C s a

n n u a ll y, a n d f o ur w e ll s w e r e sa mp l e d f or VO C s se m i- a n n u a ll y. I n J u l y 2007, t

h r ee g rou n d w ate

r mo n i t or i n g w e ll s ( W

- 22, W

- 25

, a n d L F

- 2 )

a n d t h r ee e x t r act i o n w e l l s ( E

- 3, E

- 5, a

n d E

- 7 ) w e r e aba n d o n e d a n d se a l e d i n a c c ord a n c e w i t h D e p a r t m e n t o f Wate r R e s o ur ces ( D W R ) g u i d e l i n e s ( L F R , 200

7 b )

. S a m p l i n g h a d s h o w n t h at VO C

c o n c e n t r at i o n s i n t h ese w e ll s h a d bee n c o n s i st e n t l y be l o w c l ea n

- u p st a n d a rd s. T h e w e ll d est ru ct i o n w as p e r f or m e d u n d e r C a l i f or n i a S tat e D e p a r t m e n t o f H e a l t h S e r v i ces E n v i r o n m e n t a l H ea l t h D i v i s i o n p e rm i t n u m be r 0 5582 H MW. F i g

ur e 2 s h o w s t h e stat u s o f t h e
mo n i t or i n g w e ll s i n 201 0

. N o i n te rm e d i ate or d e

e p w e ll s r e m a i n ; a l l r e m a i n i n g w e ll s a r e
s h a l l o w

. O n e or mor

e o f t h e r e m a i n i n g e x t r ac t i o n w e ll s m ay be u se

d f or f u t ur e sa mp li n g if t h e

n ee d i s i d e n t i f i e d

. S i n ce O ct

o be r 2007, t h e r e m a i n i n g f o ur w e ll s h a ve be e n mo n i t or e d f or g rou n d w ate

r e l e vat i o n a n d o n e o f t h e m ( W

- 2 7 ) c o n t i n u es t o be m o n i t or e d f or VO C s.

N o O & M ac

t i v i t i es a r e c o n d u cte d r e l a t i n g t o t h e I C r e m e d y c ompo n e n t

.


### F u t ure G r o und Wa

t er R e st o ra ti o n A c t i v iti e s

T h e sa m e a ct i v i t i es w i ll c o n t i n u e i n t h e f u t ur e u n t il g rou n d w ate

r c l e a n u p s ta n d a rd s a r e
ac h i eve d a n d m a i n t a i n e d

.1 2



## V I I I

. Su mm a

r y o f P r oj e c t C osts

A ct ua l F i na l C o s t s I n A pr il 20 1 0, L F R / A r

c a d i s r e por te d t h at t h e S i te a nn u a l O & M c o sts a r e a ppro x i m ate l y $14,50 0 / yea r f or t h e g r o u n d w ate r m o n i t or i n g ( R o t h , 20 1 0 )

.


### Pre v i o u s C o st

E st i ma te T h e pr ese n t w or t h c o st, a s do c u m e n te d i n t h e R O D A m

e n dm e n t, w a s est i m ate d t o be $ 1 49,000.

C a p i ta l : 0 A n n u a l : $18,000 f

or ea c h o f fi r st 3 yea r s, t h e n $8,00 0 a n n u a l l y f or n e x t 2 yea r s , F u t ur e: $36,00

0 To ta l P r es e n t V a l u e : $143,000 a

t 7 % i n te r est r a te $149,000 a

t 5 % i n te r est r a te



### C o mpar is o n

T h e a n n u a l c o st o f t h e g r o u n d w ate r m o n i t or i n g a pp ea r s t o be w i t h i n c l o s e r a n ge t o t h e es t i m ate f rom t h e RO D A m

e n d m e n t.



### O v er si g h t C o st

s

E P A ’ s o ve r s i g h t c o sts h a ve ave r age d a ppro x i m a t e l y $3,200 p e

r y e a r w h e n t h e o n l y a c t i v i t i es

w e r e r ev i e w i n g t h e g rou n d w a

t e r mo n i t o r i n g r e p or ts. T h e c o st f or t h e 20 0 5 5

- Y ea r R ev i e w w as
a ppro x i m ate l y $49,6 0 0 ( i n c urr e d i n 200 5 )

. T h e c o s t f or t h e 2010 5

- Y ea r R ev i e w w a s
a ppro x i m ate l y $82,0 0 0 ( i n c urr e d i n 2010 a

n d 2 0 1 1 )

. T h e c o st f or pr e p a r i n g t h e P ropo se d P l a n
a n d t h e 200 7 RO D A m

e n dm e n t w as a ppro x i m ate l y $50,300 ( i n c

urr e d i n 2 0 06 a n d 2 007 )

. T h e
a nn u a l o ve r s i g h t c o s t b i l l s a r e s u mm a r i ze d i n T a b l e 4

.



## I X

. Ob s er v a tio n s and L e sso n s L e a

r ned

M o n i t or e d N at ur a l A tt e nu at i o n a pp ea r s t o h av e s u ccess f u l l y r e m e d i ate d t h e l i n ge r i n g g rou n d w ate

r c o n ta m i n a t i o n i n t h e a q u if e r

. A f te r p u mp i n

g a n d t r eat i n g t h e g rou n d w ate

r f or
a ppro x i m ate l y 10 yea r s, t h e P R P propo

se d t h at i t w as te

c h n i c a ll y i mpr act i cab l e t o r e m e d i ate t h e g rou n d w ate

r

. Th ey po i n t e d t o t h e s t ab i li za t i o n o f t h e c o n ta m i n a n t c o n c e n t r at i o n s a b o ve t h e M CL as ev i d e

n c e. W h e r eas t h e p u mp a

n d t r eat s yste m h a d bec om e i n e ff e ct i ve at m ak i n g f ur t h e r pro g r ess t o w a rd s t h e c l e a n u p l eve l

, t h ro u g h a n o t h e r a l te r n a t i ve, t h e a q u if e r w as c a p ab l e
o f a c h i e v i n g t h e M CL

. T

h e l e s s o n l ea r n e d i s t h at at So l a Op t i c a l a T I w a i v e r w as n o t

a ppropr i ate w h e r e a s M N A c o u l d be a n e ff e ct i v e t oo l f or r e d u c i n g g rou n d w ate r c o n ta m i n a t i o n t o M CL s.1 3



## X

. Op era b l e U n it C o n t

a ct I nf o r m a t io n

EP A C o n t

a c t : D a n te R odr i g u e z R e m e d i a l P ro j ect M a n a g e r U

. S

. E P A R eg i o n 9 75 H a w t h or n e S t r eet, S F D

- 8

- 2 S a n F r a n c i sc o , C A 9410

5 ( 415 ) 972

- 316 6 rodr i g u ez. d a n te @ e p a.g ov

P R P C o n t

ac t : H a hn N g u y e n S e n i or A cc o u n t M a n age r C a r l Z e i ss V i s i o n I n c

. 12121 S c r i p s S u mm

i t Dr i ve, S u i te 40

0 S a n D i eg o , C A 9

2 131

- 46 0 9 ( 858 ) 790

- 769 6 h a n h

. n g u ye n @ v i s i o n

. ze i ss.c om

P R P/S it e C o n t r ac t o r : D a r e n R o t h T ask Ma n a ge r L F R A r ca d i s 1900 P o w e l l S t r eet, 12 t h F l oor Em e r yv ill e, C A 9

4 60 8 ( 510 ) 596

- 955 8 d a r e n

. ro t h @ a r ca d i s

- u s. c om1 4



## X I

. R e fe re n c

e s

C H 2M H i ll

. 1 991. P u

b l i c H e a l t h R i s k A s s es s m e n t ; S o l a O p ti c a l U S A

, I n c. A pr i l

.

L ev i n e F r

i cke ( L F R

) . 19 8 9. E va l u a t i on o f I m p l e m e n t e d I n te r im R e m e d i a l M e a s u res a n d P r o p o s e d F i n a l R e m e d i a l M e a s u res a t S o l a O p t i c a l

, U S A I n c . Fa c i l i t y , P et a l u m a, C a l i f o r n i a. J u n e 15.

_________

_. 199 0

. R e m e d i a l I n v e s ti g a t i on R e p o r t ; S o l a O p ti c a l U S A

, I n c , P e t a l u m a, C a l i f o r n i a. D ece m be r 3.

_________

_. 200 1

. E v

a l u a ti on o f Mo n it o re d N a t u r a l A tte nu a t i on a s a R e m e d y t o M e et R e m e d i a l Ac t i on O b j e c t i v e s ; S o l a O p t i c a l U S A

, I n c ., S i t e. A pr il 4.

_________

_. 200 2

. L ette r f rom L F R t o E P A r ega rd i n g w or k p l a n t o i mp l e m e n t m o n i t or e d n at ur a l
atte n u at i o n

. O ct o be r 22.

L F R / A r ca d i s. 200 9

. G r o u nd w a ter Mo n i t o r i n g R e p or t
, J an u a r y t h r ough J un e 2 0 09, Fo r m e r So l a O p t i c a l U S A

, I n c ., Fa c i l it y, 1500 C ad

er L an e , P e t a l u m a, C a l i f o r n i a. S e p te m be r 1.

R o t h

, D a r e n

. 2010. (P r

o j e ct G e o l o g i s t
, A r c a d i s, E m e r yv ill e, C a

l i f or n i a )

. P e r s o n a l c o m m u n i c at i o n wi t h Ah nn a West r i c h o f CD M, Wa

l n u t Cr eek, C a l if or n i a. Ma r c h 1 7

.

U n i te d S tates E n

v i ro n m e n ta l P ro tec t i o n A g e n cy ( E P A ) . 19

9 1. R e c o r d o f D e c i s i on, S o l a O p t i c a l S i te. S e p te m be r 27.

_________

_. 200 5 a. S e c o n d F i v e

- Y e a r R e v i e w R e p o rt f o r S o l a O p ti c a l U S A

, I n c

. Sup er f u n d S i te
, Sono m a C oun t y, C a l i f o r n i a. S e p te m be r

.

_________

_. 200 7 b. R e c o r d o f D e ci s i on A m e n d m e n t f o r t h e S o l a O p t i c a l U S A

, I n c . Sup er f und S i te
, P et a l u m a, C a l i f o r n i a. Ma r c h 30

.

_________

_. 200 8

. L ette r f rom E P A t o C a r l Z e i ss V i s i o n a n d L F R r ega rd i n g A ppro va l o f R e m e d i a l D e s i g n , So l a O p t i ca l S u p e r f u n d S i te. F e

b ru a r y 20.1 5 

### [Th i s pa g e i n t e n t i o n al l y le f t b la n k ]1 6



## X II

. T a b l e s a nd Fig u re s1 7 T a b l e 1 R O D

- Sp ec i fi e d M C L s a nd D r i n k i ng Wa t e r S t a n d a r d s So l a O p t i ca l U S A , I n c ., Sono m a C oun t y , C A

C h e m ic al D r i n ki ng W a t e r S t a nd a rd ( μg / L ) R A O ( μg / L ) S t a te F e d e r al

1
, 1 -DCE 6 7 6
1
, 1 -DCA 5 NE 5
1
, 1
, 1

- T CA 20 0 20 0 20 0
F r eon 11 3 1
, 20 0 NE 1
, 20 0

N E = non e e s t ab li s he d1 8 

### T a b l e 2 C hrono l o g y o f Si t e E v e n t s S o l a O p t i c a l U S A , I n c ., S onom a C oun t y , C A

Da t e E v e nt

1978

- 2 00 1 S ola o pe r a t e s a s oph t ha l m i c l en s m a n u f a c t u r i ng f a c i li t y

. 1978

- 1 98 5 S i x 1
, 000

- ga l lon unde r g r o u nd s t o r a ge t a n k s (US T s ) a r e u s ed t o s t o r e 1
, 1
, 1- tr ic h lo r o e t h a ne ( 1
, 1
, 1

- T CA), a c e t o ne , a nd m e t h an o l

. 198 2 V ola t i le o r ga n ic c o m po u n d s ( V O C s ) a r e d e t e c t ed in s h a llo w g r ound w a t e r in i m m ed i a t e
v icini t y o f US T s

. 198 3 T he C ali f o r n ia R e gi o nal W a t e r Q uali t y C on t r ol B oa r d

– S an F r an c i s c o B a y R e g ion ( W a t e r B o a r d ) o r de r s a g r ou nd w a t e r in v e s t i g a t i o n

. J ul y 1 9 8 5 S ola r e m o v e s si x 1
, 000

- ga l lo n US T s

. J ul y 1 9 8 6 S ola c on d u c t s s oi l g a s a n d s o i l bo r i ng i n v e s t iga t ion

. M a x i m u m de t e c t ion o f 1 50
m i l lig r a m s pe r li t e r ( m g / L ) 1
, 1
, 1

- T CA in s o i l g a s

. N o v e m be r 1 98 6 T r a c e c o n c e n tr a t io n s o f V O C s a r e d e t e c t ed in C i t y o f P e t a l u m a St a t io n 5 m un i c i pal

w a t e r s uppl y w ell
, lo c a t e d ap p r o x i m a t el y 300 f ee t do w ng r ad i en t o f t he S i t e

. A p r il 1 98 7 W at e r B o a r d i s s u e s S i t e C le an U p O r de r (D o ck e t # 8 7

- 0 3 8 ) r equi r ing S ola t o c on s tr u c t a g r ound w a t e r e x tr a c t i on a nd t r e a t m e n t s ys t e m ( G W T S)

. M a y 198 7 W at e r B o a r d r e f e r s s i t e t o E P A f o r i n c l u s i on o n t h e N a t i ona l Pr io r i t i e s L i s t (NP L )

. M a y 198 7 EPA S pe c i al N o t i c e L e tt e r p r o po s e s a ddi t io n al R e m e d ial I n v e s t i ga t i on (RI) a c t i v i t i e s a n d p r epa r a t i o n o f a F e a s i bi l i t y St u d y ( F S) f o r t h e S i t e

. O c t obe r 198 7 S ola i n s t al l s a G W T S

, w hi c h is f ull y o pe r a t ion a l b y A u g u s t 1 9 88

. J un e 19 88 C i t y o f P e t a lu m a c ea s e s ope r a t ion o f St a t ion 5 w ell

. O c t obe r 198 9 S ola a nd C i t y o f P e t a lu m a e n t e r w r i tt en ag r ee m en t t o c ea s e ope r a t io n s a t S t a t i on 5 w ell
un t i l s u c h pu m pi n g w ould n o l onge r ha v e t h e po t en t ial t o i m pede an y r e m ed i al
m e a s u r e s a t t he S i t e

. O c t obe r 198 9 EPA is s ue s a d m i n is t r a t i v e o r d e r (D o c k e t # 89

- 22 ) f o r RI/ F S; addi t io n al s oi l a n d s o il ga s s a m pl i ng c on d u c t ed u nde r E P A o v e r si g h t.
Feb r ua r y 1 99 0 S i t e w a s p l a c e d o n t he N P L

. A p r il 1 99 0 U s e o f S t e r o ’ s p r i v a t e w a t e r s u ppl y w ell d i sc o n t i n u e s ; S o l a r e m o v e s pu m pi n g s y s t e m and a g r e e s t o pa y f o r m u n i c i p al w a t e r s u ppl y

. D e c e m be r 1 99 0 S ola s u b m i t s RI

. J un e 19 91 S ola s u b m i t s F S w i t h d e t a i led e v alua t i on o f e n ha n c e m en t s t o c u rr e n t G W T S r e m ed y , i

. e ., in s t a l lin g t w o addi t io n al s h allo w e x tr a c t ion w el l s a n d c on v e rt ing t w o de e p m oni t o r i n g
w ell s in t o e x tr a c t io n w ell s

. S ep t e m be r 199 1 EPA is s ued a R e c o r d o f D e c i si on (R O D), s e lec t in g e x pan si on and c on t in u ed o pe r a t ion
o f t he e x is t ing G W T S s y s t e m , w i t h o ff- si t e d i s p o s a l o f tr ea t e d e ff l u en t. C on c lu d e s t ha t
s oi l s d o n o t p o s e un a cc e p t a bl e r i s k

. J an u a r y 199 2 EPA is s ue s A d m in i s tr a t i v e O r d e r (D o c k e t # 92

- 07 ) f o r R e m e d ial D e si g n /R e m ed i al A c t i o n

.1 9 

### T a b l e 2 (C on t i nu e d )

Da t e E v e nt

Feb r ua r y 1 99 2 R e m e d ial D e s i gn /R e m e d ial A c t ion W o r k P lan s u b m i tt ed t o E PA. S pe c i f i e d e n ha n c e d G W T S s y s t e m

. J ul y 1 9 9 2 E nha n c ed e x tr a c t ion s y s t e m s t a rt ed

. T h i s i n c l ude d t w o ne w s hal l o w m oni t o r ing w el l s and t h e c on v e r s ion o f t w o de e p m o ni t o r ing w el l s i n t o e x tr a c t i on w ell s

. A ugu s t 1 9 9 2 C on s tr u c t i on c o m ple t e a n d i n t e r i m cl o s e ou t r e po rt si g ned : e i gh t e x tr a c t i o n w ell s , li q ui d pha s e c a r bo n tr e a t m e n t

. J an u a r y 199 3 P ubl i c H e a l t h A ss e s s m e n t R e po rt c on c lu d e s no a ppa r en t pu bli c he a l t h ha z a r d a t t h e S i t e b e c a u s e c o n t a m in a t ed g r ound w a t e r i s n o t c u rr en t l y a s o u r c e o f d r in k ing w a t e r. Fu t u r e e x po s u r e s w e r e c o n si d e r ed u nl i k el y i f t h e g r o u nd w a t e r e x tr a c t ion s y s t e m
r edu c e s c o n c e n tr a t i on s t o le v e ls b elo w hea l t h c o n c e r n s

. N o v e m be r 1 99 6 S ola s u b m i t s r e q ue s t f o r a T e c hni c al I m p r a c t i c a bi l i t y ( T I) W ai v e r be c a u s e t he C ali f o r n i a D epa rt m en t o f P u b l i c H e a l t h m a x i m u m c o n t a m i n an t l e v el s ( M C L s ) h ad n o t b e en a c h i e v ed t h r ou g hou t t he S i t e w i t h a c t i v e g r ound w a t e r e x tr a c t ion a ft e r eig h t y ea r s o f pu m p ing

. M a r c h 199 7 EPA s t a t e d t h a t a T I w ai v e r c o uld n o t b e de t e r m ine d w i t hou t addi t io n al i n f o r m a t i on , inc l ud i ng t u r ni n g o f f t h e e x tr a c t ion w ell s an d tr ea t m e n t s ys t e m f o r t w o q u a rt e r s a n d
e v alua t i ng p o t e n t i a l r e b ou n d d u r ing qua r t e r l y m oni t o r i n g f o r s i x m on t h s

. G W T S s h u t do w n a t t h i s t i m e

. N o v e m be r 1 99 7 N o r ebo u nd n o t e d du r ing end o f 6

- m on t h t e s t pe r io d . S o l a a band o n s 17 g r ou n d w a t e r
m on i t o r i ng w ell s and 4 p i e z o m e t e r s t ha t ha v e b een a t n o n
- d e t e c t (ND) l e v el s o r b elo w t he M C L s and d e c r ea s e s m o ni t o r in g fr e q ue n c y fr o m qua r t e r l y t o s e m i an n ual

. S ep t e m be r 200 0 F i r s t F i v e
- Y ea r R e v ie w and s i t e i n s p e c t i o n

. A p r il

- M a y 200 1 A band o n m e n t o f 34 m o ni t o r i n g , e x tr a c t io n an d p i e z o m e t e r s a t s i t e A p r il 2 00 1 E x tr a c t i o n w ell s E- 5 , E- 6 , E

- 7
, and E- 1 1 w e r e de c o m m i ss i o n ed i n p r e p a r a t i on f o r p r op o s ed de v el o p m e n t o f a d j a c en t p r o p e rt y ( p u m p s pu l led a nd w ellhe a d p i pi n g
r e m o v ed )

. N o v e m be r 6
, 2 0 01 t o J an u a r y 13
, 2 00 2 D is m a n t l ing o f G W T S s y s t e m c o m ple t ed . E x tr a c t i o n w ell s E

- 1 , E- 2 , E- 3 , E- 4
, and E- 10 w e r e al s o d e c o m m i s si on ed a t t h i s t i m e

. M a y 200 1 M W

- 19 d e s tr o y ed t o a cc o m m o da t e si t e de v e l op m en t. E

- 7 a d ded t o m o ni t o r in g p r og r a m a s a r ep l a c e m e n t w ell

. S ep t e m be r 200 2 EPA r equ e s t s a w o r k p l an t o i m pl e m e n t m oni t o r ed na t u r al a t t enua t io n ( M NA) a t t he S i t e

. O c t obe r 200 2 S ola s u b m i t s W o r k P l an t o i m p le m e n t M NA ( Le v ine F r i ck e [ L F R], 20 0 2b ). A ls o s u b m i t s
r equ e s t t o ab a nd o n a n d d e s tr o y si x f o r m e r m o ni t o r in g an d e x tr a c t i on w ell s

. D e c e m be r 2 00 2 EPA app r o v e s t h e M NA E v al u a t io n R epo r t / W o r k P l a n

. G r o u nd w a t e r m o n i t o r ing pla n f u rt he r m o d i f i ed i n J anua r y 20 03

. A p r il 2 00 4 S i x g r ound w a t e r m o n i t o r i ng an d f o r m e r e x tr a c t i o n w ell s lo c a t ed a t t he S i t e w e r e aban d on e d ( W

- 1 4
, LF

- 25
, LF

- 26 , E- 6 , E

- 10
, and E

- 11 ), und e r D e s tr u c t i on P e r m i t # 4245
, C oun t y o f S on o m a

– D e pa rt m en t o f H e a l t h S e r vi c e s ( CSDHS).
J un e 20 05 S ola s u b m i t s G r ou n d w a t e r M oni t o r i ng a nd A d di t ion a l S i t e A c t ivi t ie s R epo r t ( LF R, 2005 )

. T hi s r epo r t i n cl u ded da t a fr o m g r ound w a t e r m o n i t o r i ng e v e n t s fr o m M a y 2003 t h r o ugh M a y 2005.
S ep t e m be r 200 5 S e c o n d F i v e
- Y ea r R e v ie w an d si t e i n s p e c t i on (EPA, 200 5 a )

.2 0 

### T a b l e 2 (C on t i nu e d )

Da t e E v e nt

A ugu s t 2 0 0 6 S ola s u b m i t s G r ou n d w a t e r M oni t o r i ng a nd A d di t ion a l S i t e A c t ivi t ie s R epo rt ( LF R, 2006 )

. T hi s r epo r t i n cl u ded da t a fr o m g r ound w a t e r m o n i t o r i ng e v e n t s in O c t o b e r 2 0 05 a nd J un e 20 0 6

. T hi s r epo r t a l s o i n cl u d ed a r eq u e s t t o a ba n don t h r ee g r ound w a t e r
m on i t o r i ng w ell s ( W

- 22
, W

- 2 5, and L F

- 2 ) a nd t h r ee e x tr a c t i o n w ell s (E- 3
, E- 5
, a nd E- 7 )

. J an u a r y 200 7 EPA s u b m i t s Pr o p o s e d P l a n t o pu b li c en t i t l e d EPA Pr o po s e s A m end i ng t he C l e an
- u p P lan f o r C on t a m ina t e d G r ou nd w a t e r, S o la O

p t i c a l USA, I n c

. S upe rf

u nd S i te (EPA, 200 7 a )

. Feb r ua r y 2 00 7 S ola s u b m i t s G r ou n d w a t e r M oni t o r i ng a nd A d di t ion a l S i t e A c t ivi t ie s R epo rt ( LF R, 2 0 07a ). T h i s r e p o rt i n c l u ded d a t a f r o m t he g r ou n d w a t e r m o n i t o r i ng e v e n t i n O c t obe r 200 6 a n d a l s o in c lu de d a r e q u e s t t o ab a ndo n t h r e e g r ound w a t e r m o n i t o r i ng
w ell s ( W

- 22
, W

- 2 5
, a n d LF

- 2 ) and t h r ee e x tr a c t ion w ell s (E- 3 , E- 5
, a n d E- 7 )

. M a r c h 200 7 EPA is s ue s a R O D A m e nd m e n t, s el e c t i n g M NA t o a c h i e v e g r ound w a t e r c le a n
- up s t a n da r d s , i n s t i t u t i on a l c on tr ol s (IC s ) t o p r o t e c t a g ai n s t i na pp r op r ia t e u s e o f t h e c on t a m i na t e d g r o und w a t e r u n t il t h e c lean

- up s t a n da r d s a r e a c hie v e d
, a n d m oni t o r i n g o f bo t h o f t h e r e m ed y c o m p one nt s un t il cl e an
- u p s t anda r d s a r e a c h i e v ed a n d s u s t ai n ed

. T he goal f o r M NA is aq u i f e r r e s t o r a t ion (EPA, 2 0 07b )

. A ugu s t 2 0 0 7 A C ondi t io n al U s e P e r m i t app li c a t i on i s s u b m i t t ed t o t he C i t y o f P e t a lu m a

– C o m m un i t y D e v elop m en t D e pa r t m en t t o r elo c a t e t he H a r v e s t C h r i s t i an S c ho o l (HCS) t o 150 0 C ade r Lane (HCS, 2007 ) . S o l a s ub m i t s r e p o rt r e ga r d ing t he w ell ab ando n m e n t a c t i v i t i e s in J ul y 2 0 07 ( L F R, 2 0 07 c ).
S ep t e m be r 200 8 S ola s u b m i t s G r ou n d w a t e r M oni t o r i ng a nd A d di t ion a l S i t e A c t ivi t ie s R epo rt ( LF R, 2 0 08a ). T h i s r e p o rt i n c l u ded d a t a f r o m t he g r ou n d w a t e r m o n i t o r i ng e v e n t i n A p r i l 2008

. T h i s r e po rt a l s o d e sc r i b ed t h e w o r k a s s o c ia t ed w i t h t h e c o n v e r si o n o f t he W

- 27
s t o v e
- p i pe w ell b o x

t o a f l u s h m ou n t ed w ell bo x

. T hi s w o r k w a s c on d u c t ed a t t he r eq u e s t
o f RN M Pr ope rt ies
, w hi c h i s a n ag e n t t o RN M C ade r, LL C (R N M ), t he c u r r en t o w ne r s o f t he au x ilia r y 1 1 a c r e s , in o r de r f o r t h e m t o i n s t a ll a pa r ki n g l ot in t h e a r e a o f t he w ell a s pa rt o f s i t e d e v elo p m en t a c t i v i t ies ( LF R, 2 0 08a )

. N o v e m be r 2 00 8 T he CSDHS s ub m i t s a N o t i c e o f P o t e n t i a l G r ou n d w a t e r C on t a m ina t i on l e tt e r t o c o n s t i t uen t s w ho o w n p r ope rt y w i t hin 1⁄4

- m i l e o f t he S o la S i t e (CSDHS-EHD, 2008 )

. D e c e m be r 2 00 8 S ola s u b m i t s G r ou n d w a t e r M oni t o r i ng R e po rt ( L F R, 2 0 08b ) . T hi s r epo r t i n cl u ded da t a fr o m t he g r ound w a t e r m o n i t o r i ng e v en t in S e p t e m be r 20 0 8

. S ep t e m be r 200 9 S ola s u b m i t s G r ou n d w a t e r M oni t o r i ng R e po rt ( L F R/Ar c a d i s , 2009 ). T h i s r e po rt in c lud e d da t a f r o m t he g r ou n d w a t e r m o ni t o r i ng e v e n t i n M a y 2009

. M a y 201 0 S ola s u b m i t s G r ou n d w a t e r M oni t o r i ng R e po rt ( L F R/Ar c a d i s , 2010 ). T h i s r e po rt in c lud e d da t a f r o m t he g r ou n d w a t e r m o ni t o r i ng e v e n t s J ul y t h r ou g h D e c e m be r 200 9.
O n
- goin g G r ound w a t e r m o ni t o r in g o f on e r e m ai n ing s h a llo w g r ou n d w a t e r w ell

. T he ne x t
m on i t o r i ng e v en t w a s c o n d u c t ed i n J u ne 2 010 ( r epo r t f o rt h c o m i n g ).2 1 T a b l e 3 Groun d w ater

- Qu a li t y Data P r i m a r y V O Cs (1997 t o P r ese n t) For m e r S o l a Op t i ca l U

. S

. A ., I n c

. , F ac i li ty

P eta l u m a , Ca li f o r n ia A ll c o n c en t

ra t i o n s e x pre s s ed i

n m i c rogra m s per l

i t er ( μ g / l)

W e l l I D S a m p l e

Date L a b M et h od 1 , 1-DC E 1 , 1-D C A 1 , 2-D C A 1 , 1 ,1

- T C A T C E Fr e on 113 W

- 14 20

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- 9 7 E P A 80 1 0 1 9 5 2 < 0

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. 0

12

- A p r- 0 0 E P A 82 6 0 B 1

. 0 1

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 12

- A p r- 0 0 E P A 82 6 0 B 1

. 1 1

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

8 -S e p

- 0 0 C & T E P A 82 6 0 B 1

. 2 2

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 8 -S e p

- 0 0 C & T E P A 82 6 0 B 1

. 0 2

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

2

- A p r- 01 C & T E P A 82 60 B < 0

. 5 0

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 2

- A p r- 01 C & T E P A 82 60 B < 0

. 5 0

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

19 -O c t

- 0 1 C & T E P A 82 60 B 0

. 9 1

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16

- A p r- 0 2 C & T E P A 82 60 B 0

. 6 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 08 -O c t

- 0 2 C & T E P A 82 60 B 0

. 5 0

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

*** 06

- A p r- 0 4
W

- 19 16 -O c t

- 9 8 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0

17

- M a r

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 0

. 7 <. 5 <. 5 <. 5 <. 5 < 1

. 0 23 -S e p

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 0

. 9 <. 5 <. 5 <. 5 <. 5 < 5

. 0 12

- A p r- 0 0 E P A 82 6 0 B 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 8 -S e p

- 0 0 C & T E P A 82 6 0 B 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 2

- A p r- 01 C & T E P A 82 60 B 0

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

* * * 14

- M a y

- 01
W

- 22 16 -O c t

- 9 8 E P A 80 1 0 2

. 7 1

. 6 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0

17

- M a r

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 3 1

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 23 -S e p

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 2

. 3 1

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 12

- A p r- 0 0 E P A 82 6 0 B 2

. 2 1

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 8 -S e p

- 0 0 C & T E P A 82 6 0 B 1

. 4 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 2

- A p r- 01 C & T E P A 82 60 B 2

. 4 1

. 6 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 19 -O c t

- 0 1 C & T E P A 82 60 B 1

. 3 0

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16

- A p r- 0 2 C & T E P A 82 60 B 1

. 7 1

. 2 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 08 -O c t

- 0 2 C & T E P A 82 60 B 1

. 3 1

. 0 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 22 -O c t

- 0 3 C & T E P A 82 60 B 1

. 0 0

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16 -N ov

- 0 4 C & T E P A 82 60 B 1

. 5 0

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 20 -O c t

- 0 5 C & T E P A 82 60 B 1

. 0 0

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 26 -O c t

- 0 6 C & T E P A 82 60 B 0

. 7 0

. 6 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

* * * 03

- J u l

- 0 7
W

- 25 16

- J u n

- 9 7 E P A 80 1 0 4

. 1 1

. 8 < 0

. 5 0

. 5 < 0

. 5 < 0

. 5 d u p l i c at e 16

- J u n

- 9 7 E P A 80 1 0 3

. 8 1

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

10 -S e p

- 9 7 E P A 80 1 0 2

. 4 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 d u p l i c at e 10 -S e p

- 9 7 E P A 80 1 0 2

. 7 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

12

- J u n

- 9 8 E P A 80 1 0 1

. 9 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 16 -O c t

- 9 8 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 d u p l i c at e 16 -O c t

- 9 8 E P A 80 1 0 3

. 1 1

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0

17

- M a r

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 3

. 3 1

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 23 -S e p

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 3

. 3 1

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 12

- A p r- 0 0 E P A 82 6 0 B 3

. 9 1

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 8 -S e p

- 0 0 C & T E P A 82 6 0 B 2

. 4 1

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 2

- A p r- 01 C & T E P A 82 60 B 2

. 9 1

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 02 2 T a b l e 3 Groun d w ater

- Qu a li t y Data P r i m a r y V O Cs (1997 t o P r ese n t) For m e r S o l a Op t i ca l U

. S

. A ., I n c

. , F ac i li ty

P eta l u m a , Ca li f o r n ia A ll c o n c en t

ra t i o n s e x pre s s ed i

n m i c rogra m s per l

i t er ( μ g / l)

W e l l I D S a m p l e

Date L a b M et h od 1 , 1-DC E 1 , 1-D C A 1 , 2-D C A 1 , 1 ,1

- T C A T C E Fr e on 113 19 -O c t

- 0 1 C & T E P A 82 60 B 2

. 7 1

. 2 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16

- A p r- 0 2 C & T E P A 82 60 B 2

. 3 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 08 -O c t

- 0 2 C & T E P A 82 60 B 2

. 1 0

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 8

- A p r- 03 C & T E P A 82 60 B 2

. 3 0

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 22 -O c t

- 0 3 C & T E P A 82 60 B 1

. 6 0

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 17

- M a y

- 04 C & T E P A 82 60 B 1

. 3 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16 -N ov

- 0 4 C & T E P A 82 60 B 1

. 2 0

. 5 J < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 3

- M a y

- 05 C & T E P A 82 60 B 1

. 5 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 20 -O c t

- 0 5 C & T E P A 82 60 B 1 0

. 4 J < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 6

- J u n

- 0 6 C & T E P A 82 60 B 1

. 3 0

. 4 J < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 26 -O c t

- 0 6 C & T E P A 82 60 B 0

. 9 0

. 4 J < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 11

- A p r- 0 7 C & T E P A 82 60 B 0

. 7 0

. 3 J < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

* * * 03

- J u l

- 0 7
W

- 27 02

- J u l

- 9 7 E P A 80 1 0 7

. 1 1 2 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

10 -S e p

- 9 7 E P A 80 1 0 6

. 8 1 2 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 d u p l i c at e 10 -S e p

- 9 7 E P A 80 1 0 6

. 4 1 2 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

11

- J u n

- 9 8 E P A 80 1 0 1 0 1 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 d u p l i c at e 11

- J u n

- 9 8 E P A 80 1 0 1 1 1 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

16 -O c t

- 9 8 E P A 82 6 0 A ( 80 1 0 ) 1 2 1 5 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 17

- M a r

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 1 1 1 6 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 23 -S e p

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 9

. 9 1 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 12

- A p r- 0 0 E P A 82 6 0 B 1 0 2 0 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 8 -S e p

- 0 0 C & T E P A 82 6 0 B 6

. 3 1 6 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

** 21 -N ov

- 0 0 C & T E P A 82 6 0 B 3

. 6 1 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

* 21 -N ov

- 0 0 C L I E P A 82 6 0 A < 0

. 5 1 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

2

- A p r- 01 C & T E P A 82 60 B 7

. 1 1 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 19 -O c t

- 0 1 C & T E P A 82 60 B 8

. 3 1 6 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 19 -O c t

- 0 1 C & T E P A 82 60 B 7

. 9 1 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

16

- A p r- 0 2 C & T E P A 82 60 B 4

. 9 1 2 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 08 -O c t

- 0 2 C & T E P A 82 60 B 5

. 6 1 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 8 -O ct

- 0 2 C & T E P A 82 60 B 5

. 7 1 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

8

- A p r- 03 C & T E P A 82 60 B 4 1 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 8

- A p r- 03 C & T E P A 82 60 B 4

. 9 1 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

22 -O c t

- 0 3 C & T E P A 82 60 B 4

. 7 2 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 17

- M a y

- 04 C & T E P A 82 60 B 3

. 9 1 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 17

- M a y

- 04 C & T E P A 82 60 B 3

. 9 1 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

16 -N ov

- 0 4 C & T E P A 82 60 B 4

. 8 2 0 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 16 -N ov

- 0 4 C & T E P A 82 60 B 4

. 9 2 0 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

3

- M a y

- 05 C & T E P A 82 60 B 3

. 8 2 0 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 3

- M a y

- 05 C & T E P A 82 60 B 3

. 6 1 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

20 -O c t

- 0 5 C & T E P A 82 60 B 2

. 6 1 6 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 20 -O c t

- 0 5 C & T E P A 82 60 B 3

. 2 1 7 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

6

- J u n

- 0 6 C & T E P A 82 60 B 3 1 6 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 26 -O c t

- 0 6 C & T E P A 82 60 B 1

. 5 1 2 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 26 -O c t

- 0 6 C & T E P A 82 60 B 1

. 6 1 2 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

11

- A p r- 0 7 C & T E P A 82 60 B 1

. 2 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 19 -O c t

- 0 7 C & T E P A 82 60 B 1

. 9 8

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 4

- A p r- 08 C & T E P A 82 60 B 1

. 2 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 29 -S e p

- 0 8 C & T E P A 82 60 B 2

. 2 1 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 15

- M a y

- 09 C & T E P A 82 60 B 0

. 6 4

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0
30 -D e c

- 0 9 C & T E P A 82 60 B 0

. 8 6

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 23

- J u n

- 1 0 C & T E P A 82 60 B 0

. 3 J 2

. 6 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 02 3 T a b l e 3 Groun d w ater

- Qu a li t y Data P r i m a r y V O Cs (1997 t o P r ese n t) For m e r S o l a Op t i ca l U

. S

. A ., I n c

. , F ac i li ty

P eta l u m a , Ca li f o r n ia A ll c o n c en t

ra t i o n s e x pre s s ed i

n m i c rogra m s per l

i t er ( μ g / l)

W e l l I D S a m p l e

Date L a b M et h od 1 , 1-DC E 1 , 1-D C A 1 , 2-D C A 1 , 1 ,1

- T C A T C E Fr e on 113 d u p l i c at e 23

- J u n

- 1 0 C & T E P A 82 60 B 0

. 3 J 2

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0
W

- 33 16

- J u n

- 9 7 E P A 80 1 0 3

. 1 0

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

9 -S e p

- 9 7 E P A 80 1 0 2

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 12

- J u n

- 9 8 E P A 80 1 0 1

. 6 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

* * 21 -N ov

- 0 0 C & T E P A 82 6 0 B 1

. 6 0

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

* 21 -N ov

- 0 0 C L I E P A 82 6 0 A 1

. 3 0

. 5 3 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

*** 15

- M a y

- 01
L F

- 2 20

- J u n

- 9 7 E P A 80 1 0 3 0 6 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

09 -S e p

- 9 7 E P A 80 1 0 4

. 6 2

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 09

- J u n

- 9 8 E P A 80 1 0 4 2 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 d u p l i c at e 09

- J u n

- 9 8 E P A 80 1 0 4

. 6 2 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

16 -O c t

- 9 8 E P A 80 1 0 5

. 0 2

. 3 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 17

- M a r

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 5

. 5 2

. 2 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 23 -S e p

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 5

. 0 2

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 12

- A p r- 0 0 E P A 82 6 0 B 5

. 4 2

. 3 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 8 -S e p

- 0 0 C & T E P A 82 6 0 B 4

. 1 2

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 2

- A p r- 01 C & T E P A 82 60 B 5

. 3 2

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 19 -O c t

- 0 1 C & T E P A 82 60 B 3

. 3 1

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16

- A p r- 0 2 C & T E P A 82 60 B 3

. 9 1

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 08 -O c t

- 0 2 C & T E P A 82 60 B 4

. 1 2

. 3 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 22 -O c t

- 0 3 C & T E P A 82 60 B 2

. 6 2

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16 -N ov

- 0 4 C & T E P A 82 60 B 1 0

. 4 J < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 20 -O c t

- 0 5 C & T E P A 82 60 B 2

. 0 1

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 26 -O c t

- 0 6 C & T E P A 82 60 B 1

. 1 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

* * * 03

- J u l

- 0 7
L F

- 2 5 19

- J u n

- 9 7 E P A 80 1 0 2

. 8 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

09 -S e p

- 9 7 E P A 80 1 0 3

. 1 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 d u p l i c at e 09 -S e p

- 9 7 E P A 80 1 0 2

. 6 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

10

- J u n

- 9 8 E P A 80 1 0 2

. 3 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 d u p l i c at e 10

- J u n

- 9 8 E P A 80 1 0 2

. 4 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

16 -O c t

- 9 8 E P A 80 1 0 2

. 5 1 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 17

- M a r

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 3 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 23 -S e p

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 2

. 6 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 12

- A p r- 0 0 E P A 82 6 0 B 2

. 6 0

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 8 -S e p

- 0 0 C & T E P A 82 6 0 B < 0

. 5 1

. 2 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 2

- A p r- 01 C & T E P A 82 60 B 2

. 8 1

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 19 -O c t

- 0 1 C & T E P A 82 60 B 1

. 8 0

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16

- A p r- 0 2 C & T E P A 82 60 B 2

. 2 0

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 08 -O c t

- 0 2 C & T E P A 82 60 B 1

. 7 0

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

*** 06

- A p r- 0 4
L F

- 2 6 19

- J u n

- 9 7 E P A 80 1 0 4

. 2 1 < 0

. 5 0

. 6 < 0

. 5 < 0

. 5 d u p l i c at e 19

- J u n

- 9 7 E P A 80 1 0 4

. 1 0

. 9 < 0

. 5 0

. 6 < 0

. 5 < 0

. 5

09 -S e p

- 9 7 E P A 80 1 0 2

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 10

- J u n

- 9 8 E P A 80 1 0 4

. 3 1

. 1 < 0

. 5 0

. 5 < 0

. 5 < 0

. 5 d u p l i c at e 10

- J u n

- 9 8 E P A 80 1 0 4

. 2 1

. 1 < 0

. 5 0

. 5 < 0

. 5 < 0

. 5

23 -S e p

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 3

. 6 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 12

- A p r- 0 0 E P A 82 6 0 B 3

. 2 1

. 0 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 8 -S e p

- 0 0 C & T E P A 82 6 0 B 2

. 5 0

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 2

- A p r- 01 C & T E P A 82 60 B 2

. 6 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0
19 -O c t

- 0 1 C & T E P A 82 60 B 1

. 9 0

. 6 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16

- A p r- 0 2 C & T E P A 82 60 B 2

. 3 0

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 08 -O c t

- 0 2 C & T E P A 82 60 B 2 0

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 02 4 T a b l e 3 Groun d w ater

- Qu a li t y Data P r i m a r y V O Cs (1997 t o P r ese n t) For m e r S o l a Op t i ca l U

. S

. A ., I n c

. , F ac i li ty

P eta l u m a , Ca li f o r n ia A ll c o n c en t

ra t i o n s e x pre s s ed i

n m i c rogra m s per l

i t er ( μ g / l)

W e l l I D S a m p l e

Date L a b M et h od 1 , 1-DC E 1 , 1-D C A 1 , 2-D C A 1 , 1 ,1

- T C A T C E Fr e on 113

*** 06

- A p r- 0 4
E

- 3 18

- J u n

- 9 7 E P A 80 1 0 7

. 6 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

11 -S e p

- 9 7 E P A 80 1 0 9 1 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 11

- J u n

- 9 8 C & T E P A 80 1 0 1 5 1 8 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 8

- A p r- 03 C & T E P A 82 60 B 4

. 2 3

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 22 -O c t

- 0 3 C & T E P A 82 60 B 3

. 6 2

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 17

- M a y

- 04 C & T E P A 82 60 B 4

. 8 3

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16 -N ov

- 0 4 C & T E P A 82 60 B 1

. 8 1

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 3

- M a y

- 05 C & T E P A 82 60 B 0

. 9 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 20 -O c t

- 0 5 C & T E P A 82 60 B 2

. 0 1

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 6

- J u n

- 0 6 C & T E P A 82 60 B 1

. 9 1

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 6

- J u n

- 0 6 C & T E P A 82 60 B 2

. 0 1

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

26 -O c t

- 0 6 C & T E P A 82 60 B 2

. 2 2

. 3 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 11

- A p r- 0 7 C & T E P A 82 60 B 1

. 8 2

. 3 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

* * * 05

- J u l

- 0 7
E

- 5 18

- J u n

- 9 7 E P A 80 1 0 1 0 4 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

11 -S e p

- 9 7 E P A 80 1 0 1 1 3

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 15

- J u n

- 9 8 E P A 80 1 0 9

. 7 3

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 16 -O c t

- 9 8 E P A 80 1 0 1 2 3

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 17

- M a r

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 1 3 3

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 23 -S e p

- 9 9 E P A 82 6 0 A ( 80 1 0 ) 1 5 4

. 3 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 12

- A p r- 0 0 E P A 82 6 0 B 1 2 3

. 7 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 08 -S e p

- 0 0 C & T E P A 82 6 0 B 1 2 3

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

** 21 -N ov

- 0 0 C & T E P A 82 6 0 B 1 0 3

. 6 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

* 21 -N ov

- 0 0 C L I E P A 82 6 0 A 6

. 5 2

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

2

- A p r- 01 C & T E P A 82 60 B 1 3 4

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 19 -O c t

- 0 1 C & T E P A 82 60 B 8

. 3 3

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16

- A p r- 0 2 C & T E P A 82 60 B 5

. 1 2

. 2 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 16

- A p r- 0 2 C & T E P A 82 60 B 6

. 4 2

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

08 -O c t

- 0 2 C & T E P A 82 60 B 9

. 3 3

. 3 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 8

- A p r- 03 C & T E P A 82 60 B 7

. 2 2

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 22 -O c t

- 0 3 C & T E P A 82 60 B 7

. 1 3

. 4 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 22 -O c t

- 0 3 C & T E P A 82 60 B 6

. 9 3

. 3 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

17

- M a y

- 04 C & T E P A 82 60 B 5

. 1 2

. 2 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16 -N ov

- 0 4 C & T E P A 82 60 B 4

. 5 1

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 3

- M a y

- 05 C & T E P A 82 60 B 3

. 7 1

. 8 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 20 -O c t

- 0 5 C & T E P A 82 60 B 5

. 6 2 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 6

- J u n

- 0 6 C & T E P A 82 60 B 3

. 3 1

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 26 -O c t

- 0 6 C & T E P A 82 60 B 4

. 7 1

. 9 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 11

- A p r- 0 7 C & T E P A 82 60 B 2

. 8 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 d u p l i c at e 11

- A p r- 0 7 C & T E P A 82 60 B 2

. 7 1

. 1 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

* * * 05

- J u l

- 0 7
E

- 7 18

- J u n

- 9 7 E P A 80 1 0 < 0

. 5 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

11 -S e p

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 12

- J u n

- 9 8 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 19 -O c t

- 0 1 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16

- A p r- 0 2 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 08 -O c t

- 0 2 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 22 -O c t

- 0 3 C & T E P A 82 60 B < 0

. 5 0

. 3 J < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 16 -N ov

- 0 4 C & T E P A 82 60 B < 0

. 5 0

. 3 J < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 20 -O c t

- 0 5 C & T E P A 82 60 B < 0

. 5 0

. 3 J < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 26 -O c t

- 0 6 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 02 5 T a b l e 3 Groun d w ater

- Qu a li t y Data P r i m a r y V O Cs (1997 t o P r ese n t) For m e r S o l a Op t i ca l U

. S

. A ., I n c

. , F ac i li ty

P eta l u m a , Ca li f o r n ia A ll c o n c en t

ra t i o n s e x pre s s ed i

n m i c rogra m s per l

i t er ( μ g / l)

W e l l I D S a m p l e

Date L a b M et h od 1 , 1-DC E 1 , 1-D C A 1 , 2-D C A 1 , 1 ,1

- T C A T C E Fr e on 113

* * * 05

- J u l

- 0 7 F i e l d B l a n k s W

- 33

- F B 16

- J u n

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 L F

- 1 6

- F B 17

- J u n

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 L F

- 3

- F B 18

- J u n

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 L F

- 2 5

- F B 19

- J u n

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 W

- 28

- F B 20

- J u n

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 W 33

- F B 9 -S e p

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 L F

- 6

- F B 10 -S e p

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 W

- 28

- F B 9

- J u n

- 9 8 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 L F

- 1 6

- F B 10

- J u n

- 9 8 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 W

- 25

- F B 16 -O c t

- 9 8 ( 1 ) E P A 82 6 0 A ( 80 1 0 ) < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 W

- 14

- F B 17

- M a r

- 9 9 E P A 82 6 0 A ( 80 1 0 ) < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 1

. 0 W

- 19

- F B 23 -S e p

- 9 9 E P A 82 6 0 A ( 80 1 0 ) < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 27

- F B 12

- A p r- 0 0 E P A 82 6 0 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 L F

- 2 6 F B 8 -S e p

- 0 0 C & T E P A 82 6 0 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 27 F B 2

- A p r- 01 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 E X

- 7

- F B 19 -O c t

- 0 1 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 27 F B 16

- A p r- 0 2 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 14 F B 8 -O ct

- 0 2 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 F B 04 0 80 3 8

- A p r- 03 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 L F

- 2 F B 22 -O c t

- 0 3 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 27

- F B 17

- M a y

- 04 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 L F

- 2

- B 16 -N ov

- 0 4 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 5

- 0 3

- 0 5

- B 3

- M a y

- 05 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 25

- F B 20 -O c t

- 0 5 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 EB 0 6 06 0 6 6

- J u n

- 0 6 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 25

- F B 26 -O c t

- 0 6 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 25

- F B 11

- A p r- 0 7 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 27

- F B 19 -O c t

- 0 7 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 27

- F B 4

- A p r- 08 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 27

- F B 29 -S e p

- 0 8 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 27

- F B 15

- M a y

- 09 ( 2 ) E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 27

- F B 30 -D e c

- 0 9 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0 W

- 27

- F B 23

- J u n

- 1 0 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 1 Tri p B l a n k s 17

- J u n

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 TB 20

- J u n

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5

9 -S e p

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 10 -S e p

- 9 7 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 9

- J u n

- 9 8 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 12

- J u n

- 9 8 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 15

- J u n

- 9 8 E P A 80 1 0 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 * 21 -N ov

- 0 0 C L I E P A 82 6 0 A ( 80 1 0 ) < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

2

- A p r- 01 C & T E P A 82 60 B < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 0

. 5 < 5

. 0

D ata u p d at e d b y M D

. Pr oo f e d b y

.

N o t e s : ( 1 ) = C h lo r o f

o r m d e t e ct e d at 1

. 7 m ic r og r a ms p e r l it e r

. ( 2 ) = C h lo r o f

o r m d e t e ct e d at 0

. 8 m ic r og r a m p e r l it e r

.2 6 T a b l e 3 Groun d w ater

- Qu a li t y Data P r i m a r y V O Cs (1997 t o P r ese n t) For m e r S o l a Op t i ca l U

. S

. A ., I n c

. , F ac i li ty

P eta l u m a , Ca li f o r n ia A ll c o n c en t

ra t i o n s e x pre s s ed i

n m i c rogra m s per l

i t er ( μ g / l)

W e l l I D S a m p l e

Date L a b M et h od 1 , 1-DC E 1 , 1-D C A 1 , 2-D C A 1 , 1 ,1

- T C A T C E Fr e on 113 1
, 1 -D C E = 1
, 1 -D i c h lo r o e th e n e 1
, 1 -D C A = 1
, 1

- D i c h lo r o e than e 1
, 2 -D C A = 1
, 2

- D i c h lo r o e than e 1
, 1
, 1

- T C A

= 1
, 1
, 1

- T r ich lo r o e than e T C E = T r i c h lo r o e th e n e VO C s = Vo l a t i le o r g a ni c c o m p o u n d s J = E s t i m at e d v a l u e

. * = S a m p le s c oll e ct e d b y E n v i r o n

. ** = S p l i t s a m

p le c oll e ct e d b y L F R.

*** = W el l d e s t r oy e d

. A n al y tica l L a b o r at o r i e s : C & T = C u r t i s & T o m p k in s , L td., A n a l y tica l L a b o r at o r i e s , B e r k el e y , Ca l i f o r n i a. C L I = C h r o m a L a b
, I

n c., E n v i r o n m e n ta l S e r v ic e s , P le a s a nt o n , Ca l i f o r n i a.2 7 

### T a b l e 4 E P A O v e r s i gh t C o s t s

Da t e Of Bill A m ount Da t es C o v e r ed A c t i v i t i es Feb r ua r y 8
, 20 01 $3

, 3 4 5

. 5 9 11 / 1 / 0 0

– 10 / 3 1 / 0 1 1 M oni t o r in g J an u a r y 24
, 2 00 5 $9

, 1 8 6

. 1 2 11 / 1 / 0 1

– 10 / 3 1 / 0 4 2 M oni t o r in g M a r c h 20
, 2 0 0 6 $52

, 8 66

. 90 11 / 1 / 0 4

– 10 / 3 1 / 0 5 3 M oni t o r ing
, 5

- Y ea r R e v ie w J an u a r y 12
, 2 00 7 $15

, 2 99

. 89 11 / 1 / 0 5

– 10 / 3 1 / 0 6 4 M oni t o r ing , Pr o po s ed P la n M a r c h 4
, 20 08 $41

, 5 25

. 98 11 / 1 / 0 6

– 10 / 3 1 / 0 7 5 M oni t o r ing , Pr o po s ed P lan
, R O D A m en d m en t J an u a r y 23
, 2 00 9 $367 5

. 1 1 11 / 1 / 0 7

– 10 / 3 1 / 0 8 6 m on i t o r i n g J an u a r y 13
, 2 01 0 $271 6

. 4 9 11 / 1 / 0 8

– 10 / 3 1 / 0 9 7 m on i t o r i n g N o v e m be r 2 2
, 2 01 0 $45

, 1 52

. 58 11 / 1 / 0 9

– 10 / 3 1 / 1 0 8 M oni t o r ing
, 5

- Y ea r R e v ie w D e c e m be r 5
, 2 0 1 1 $43

, 2 25

. 72 11 / 1 / 1 0

– 10 / 3 1 / 1 1 9 M oni t o r ing
, 5

- Y ea r R e v ie w

R E F E R E NC E S : 1

. L t r B l a n k ( E P A ) t o S an z ar i ( S o l a O p t i c a l ) da t e d 2 / 8 / 01

. 2

. L t r B l a n k ( E P A ) t o S an z ar i ( S o l a O p t i c a l ) da t e d 1 / 2 4 / 05

. 3

. L t r B l a n k ( E P A ) t o S an z ar i ( S o l a O p t i c a l ) da t e d 3 / 2 0 / 06

. 4

. L t r B l a n k ( E P A ) t o S an z ar i ( S o l a O p t i c a l ) da t e d 1 / 1 2 / 07

. 5

. L t r B l a n k ( E P A ) t o S an z ar i ( S o l a O p t i c a l ) da t e d 3 / 4 / 08

. 6

. L t r B l a n k ( E P A ) t o M uen z (Car l Z e i s s V i s i on) da t e d 1 / 23 / 0 9

. 7

. L t r M oore ( EPA ) t o M uen z (Car l Z e i s s V i s i on) d a t ed 1 / 1 3 / 10

. 8

. L t r M oore ( EPA ) t o Nguyen (Car l Z e i s s V i s i on) d a t ed 11 / 2 2 / 10

. 9

. L t r M oore ( EPA ) t o Nguyen (Car l Z e i s s V i s i on) d a t ed 12 / 5 / 11

.2 8 

## Fig u r es

### 2y

74

1. a I ft I I I 

# 1

2 9End Treohneql Figu.K. ComentratIons of 1.147CE Venus time ifi Well W27

1 f.



### Vg F •E F; gEg FWET EA! E 8

I.1 E

3 0Figure 1 Concentrations of 1.1-13r—A - Versus Time in Weil 4 1 1r-77

cn FiT F.IFTFPOFT F.TF.W.Fg'F.TF

. ,VE.TE.'PEE2fVEK'ELTVil'Erg r ErgEVEV'EP;E 7.'? TT. 7

- 9 7 7 7 7 7 7 7 7 7, 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 co cm co co 03 cis tc. w 4,2 w uti ID at. a a a ca o a a. a a CV a La a CI a --1 -4 95 ca 49 .b} =I r.J 4. 1 . 4.. a um. [El a L-J CO 4I2. r*-1 1,) L.) r 4 4 CP. Ln CR. --J - 4 CV DP. Ea rj, 'KC

I • I -1 1

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