1

Rodriguez, Dante

From: Zimmerman, Chuck <CZimmerman@brwncald.com>Sent: Wednesday, May 06, 2015 2:43 PMTo: Seter, DavidCc: 'Oman, Jack'; Ball, Harold; Rodriguez, Dante; jrcollins@ndep.nv.gov; Jeryl Gardner;

'Tom_Olsen@nv.blm.gov'; 'Phyllis P. Hunewill'; 'tgrady@asm.state.nv.us'; manager@yerington.net; cynthiaoceguera8@gmail.com; 'Lucari, James L'; 'Halsey, Ronald H'; Dunkelman, Tom; 'Brian.S.Johnson@bp.com'; james.nolan@bp.com; Gallery, Patricia A (patricia.gallery@bp.com); Helmlinger, Andrew; 'Tom Bowden'; 'Taurus Massey'; 'sdischler@quaterra.com'; 'John Batchelder'; 'chairman@ypt-nsn.gov'; environmentaldirector@ypt-nsn.gov; ghatch@ypt-nsn.gov; 'Olsen, Tom T'; 'preacherpauly@earthlink.net'; dmcginnis@sbcglobal.net; 'david@periandsons.com'; Isham, Julian; McMillan, John (CFS); 'Ken.Greene@CH2M.com'; 'Victor.Early@ttemi.com'; 'Colin.Lee@tetratech.com'; 'Chatham, James R'; 'Duffy, William'; 'tpatton@quaterra.com'; 'mmcfalls@wrpt.us'; 'ROB LOVEBERG'; Adam.Cohen@dgslaw.com

Subject: April 2015 Monthly Report for the Yerington Mine SiteAttachments: April 2015 Monthly Report.pdf; Arimetco FMS April 2015 Monitoring Data.pdf

Categories: A08 - Arimetco

Dave: The April 2015 monthly report for the Yerington Mine Site is attached, along with the monthly Arimetco Fluid Management System (FMS) monitoring data. The original will be sent to you today by certified mail. Hard copies will be sent via regular mail to the Lyon County Library, Chairwoman Howard, Ginny Hatch, Dietrick McGinnis, Chairwoman McFalls, Cynthia Oceguera and Peggy Pauly. This e-mail serves as the submittal for the remainder of the copied recipients. Please forward this e-mail to others who may be interested in the April 2015 monthly report. Regards, Chuck Zimmerman Vice President Brown and Caldwell CZimmerman@brwncald.com T 775.283.0810 | C 775.233.5575

SEMS-RM DOCID # 1162035

Atlantic Richfield Company

Jack Oman ~Manager

May6,2015

CERIFED- RETURN RECEIPT REQUEl'IE)

Mr. Dave Seier Remadlal Project Manager U.S. Enllirunmenlal PruCactiDn Agency Region 9 75 Hawthorne S1rwt, SFD-9-1 sen Frandlco, CA 94105

4 centlerpolnle Drive LaPllma, CA. 110623-1066 (657) 529-4581 office (714) 67<Mi1t5 fax JIClc.omari@bp.com

Aplll 20111 lllonlllly Repart, Yllllnglon Mine Site, Lyon CounlJ, Nevada:

Dear Mr. 8el!er.

Admlnla1Hdlw8 Oftler ro, Rtmedlal lnVNQgatlon 111d Fwlllllty ltlldy (Rff'S), CERCLA Docat No. 9-2007-0IIOS; A*'lrllltlaaw Order on COlllent, CERCLA Docat No. ot-200M010

Pu111Ua1t to Iha abova lllferenced onl11111 ltsued by the U.S. Envtonmental Protacllon Agency. Region 9 (EPA), Allantic Richfield Compmiy (ARC) hu preparad lhia April 201& monthly report fur RUFS and Operations and Maintanance (oaM) aclivitiea at the Yerington Mine Site (Sita).

Aprll 20I& Advtll•

Sito &en 1r1v and O&M Acitifaes • Coni,iued Sltll O&M, security and bird detenant actlvltlN. Clmenll at various locatlonl (e.g.,

Main and Amlalco gatee, entrancea to buildings) indimtad no actMty of concem. • Wind dancers, bird delttrent flage, Wtllande W8iln and Bird Gerd IDWWII continued 1D be

deployed In accordance with Iha current EPA-apprond bird deterrent approech. Balloon• remained In pla:a 01111r FMS Evaporation Ponds B and C. To reduca birds from becoming habituated 1D wind dancers and flags, th888 devices - re-located aa nae ilad. Bini Gad lowlnl •,,:, 'B' and 'C' - in operation Aprl 2S-30 due ID pl'IICipitation.

• Rdlec!IVe my!# bird deterrent deV!ces were deployed at the Slot pond, VL T pond and on three blnl mitigation flags. Daclbel monitoring for pyrutachnlc dalllcea - performed on Aprl 1.

• Continued the EPA-approval bird mitigation achadulB, with at laaat lhrae monitoring viaibl par day at II ponc11 plus a fold! monitoring vlllt at lhe Amie!= FMS ponds. Obtervallons wen: made within halt an hour of daWn and dusk, with Iha other vtalt(a) conducted mtcMay.

• PWS Pond watsr llwala: Nor1h Call • 0.0 fllet; Mlddle Call• 0.0 faet; South Call • 0.0 faet. • Arimelco FMS pond llvall: Ph- 1 Pond= 4.28 fNt; FMS Evlpofation Pond A= 9.02 fNI; FMS

EVaporatlon Pond B = 4.03 feet FMS Evaporation Pond C = 5.29 reet; VL T Pond = 12.21 reet; Slol Pond = 17.19 feet. The treeboeftl level In FM$ EvaporaUon Pond A on April 30 waa approximately 1.13 fail No fluid tranafara oa:urred in April. Saa altachad monitoring data.

• Approximllilly 21,548 gallons Df solution ware pumped from the leak dltlc!Drs in April including 6,2.08 91Ilon1 bm the VI. T Pond, and 22,380 gallons l'rom Ille Slot Pond. Appn»cnllely 98,344 gallonl of IOlutlon !lave been pumped l'rom the leek deleclol'I alnce January 1, 2015. Sae allBchad monitoring data.

A BP affiliated company d

Mr. Dave Seter Yerington Monthly Report May 6, 2015 Page 2 of 4

April 2015 Activities - Continued

Site Security and O&M Activities - Continued • ARC, EPA and NDEP personnel conducted a review of select FMS components on April 2. • Per EPA direction, the 4-inch diameter pipe at the Phase Ill drain line was drained, disconnected

and reattached on April 20. Solutions that drained from the pipe were collected and discharged into FMS Evaporation Pond C.

• The evaporation pan located near PW-6 was re-established on April 1.

Site Characterization Activities • Site-wide monthly groundwater elevation measurements for monitor wells with pressure

transducers were obtained on April 29-30. • A Pit Lake water elevation of 4233.36 feet amsl was recorded on April 29 from the pressure

transducer, an increase of 0.23 feet since March 29, 2015. The pit lake elevation has risen 1.48 feet since April 29, 2014.

• No changes to the Domestic Well Monitoring or Bottled Water Programs in April. • Continued the compilation of data for inclusion in the 2014 Annual Groundwater Monitoring

Report (GMR). • Prepared for the 20 2015 groundwater monitoring event in May. • Continued the compilation of field and laboratory data for inclusion in the data summary report

(DSR) for the supplemental monitor well installation program. • Continued work on the revised Background Groundwater Water Quality Assessment (BGQA). • Phase 1 drilling and sampling around the Evaporation Ponds started on April 14 pursuant to the

EPA-approved field sampling and analysis plan (FSAP): 1) 18 temporary wells were constructed and 17 shallow zone groundwater samples were collected for chemical and hydrologic tracer analyses, and four borings were abandoned; and 2) four borings were subject to geotechnical testing (standard penetration tests or SPT) and sampling for material characteristics (moisture content, particle size analysis and liquid limit, plastic limit and plasticity index).

• Participated in a groundwater technical call on April 8 to discuss the groundwater flow model and related topics.

• Prepared for the May 7 groundwater technical meeting, including a revised presentation of an approach to assess bedrock groundwater conditions.

• Communicated with ARC and EPA regarding next steps for the Geochemical Characterization Data Summary Report including an e-mail transmittal on April 27 of thermodynamic data for two mineral species proposed for inclusion in future geochemical modeling.

• Continued the evaluation of bedrock groundwater data to support a Bedrock Characterization Work Plan.

• Continued work on the conceptual site model (CSM) and data quality objectives (DQOs) for the Wabuska Drain (OU-7) RI.

• Routine database management activities in support of Site investigations and monitoring. • Attended a Yerington Community meeting on April 2.

Planned May/June 2015 Activities

Site Security and O&M Activities • Continue routine Site O&M, security and bird deterrent activities. • Upon receipt of written notification from EPA, ARC will initiate repairs to liner holes and tears

observed along the Phase Ill Heap Leach Pad perimeter collection ditch. • Provide a hydraulic test work plan for FMS Evaporation Ponds B and C to assess the integrity of

the primary liner. • Further discuss steps for managing fluids in the Phase I Pond given the accumulation of solids.

Mr. Dave Seter Yerington Monthly Report May 8, 2015 Page3of4

Planned May/June 201& Activities • Continued

Site Characterization Activities • Continued • Continue groundwater elevation and pit lake level measurements, and meteorological monitoring. • Continue the Bottled Water Program. • Perfonn the 2Q 2015 groundwater monitoring event In May. • Continue the compilation of data for indusion in the 2014 Annual GMR and transmit the GMR. • Parfonn the 2Q 2015 domestic well groundwater monitoring event in June. • Continue discussions with EPA regarding the proposed parameter reduction list for routine

quarterly groundwater sampling. • Continue work on the Supplemental Monitor Well Installation DSR and transmit the DSR. • Continue the compilation of data to support an assessment of bedrock groundwater conditions. • Continue the preparation of the BGQA - Revision 2, and transmit the updated BGQA to EPA. • Continue groundwater and gaotechnical characterization activities around the Evaporation Ponds. • Continue discussions with EPA regarding the OU-1 and OU-3 Human Health Risk Assessments. • Continue wortcing on responses to comments from EPA dated March 18 on the Process Areas

(OU-3) Step-Out Characterization DSR, and the development of a Process Areas RI Report, including a scoping discussion with EPA.

• Continue working on the DQOs and CSM for the Wabuska Drain (OU-7) RI, and transmit the DQOs and CSM to EPA in June.

• Continue to work on a PCS closure plan for the Process Areas. • Participate in a groundwater technical meeting on May 7 to disc:u&S bedrock characterization and

the development of a contaminant transport model.

Please contact me at (857) 529-4581 or via e-mail at jack.oman@bp.com if you have any questions or comment& about the April 2015 monthly report.

Sincerely,

Jack Oman Project Manager

Attachment

cc: Harry Ball, EPA-via electronic mail Dante Rodriguez, EPA - via electronic mail Andrew Helmlinger, EPA - via electronic mail Tom Dunkelman, EPA-via electronic mail Jeff Collins, NDEP - via electronic mail Jeryl Gardner, NDEP - via elec:tronic mail Tom Olsen, BLM -via electronic mail Dan Newell, City of Yerington -via electronic mail Phyllis Hunewill - via electronic mail Rob Loveberg, Lyon County Planning Department-via electronic mail Tom Grady, Nevada State Assembly- via electronic mail Chairwoman Howard, YPT -via electronic mail Ginny Hatch, YPT - via electronic mail Deborah Dunn, YPT - via electronic mail Dietrick McGinnis, McGinnis and Associates - via eleci'onic mail Tom Bowden, Ridolfi, Inc. -via eledronic mail Chairwoman McFalls, WRPT - via electronic mail

Mr. Dave Seter Yerington Monthly Report May 6, 2015 Page 4 of 4

Cynthia Oceguera, WRPT - via electronic mail Ron Halsey, Atlantic Richfield Company - via electronic mail James Nolan, Atlantic Richfield Company - via electronic mail Patricia Gallery, Atlantic Richfield Company - via electronic mail Brian Johnson, Atlantic Richfield Company - via electronic mail John Batchelder, EnviroSolve - via electronic mail Jim Chatham, Atlantic Richfield Company - via electronic mail Rich Curley, Curley and Associates, LLC - via electronic mail Adam Cohen, Davis Graham & Stubbs - via electronic mail Bill Duffy, Davis Graham & Stubbs - via electronic mail Tom Patton, Singatse Peak Services, LLP - via electronic mail Steve Dischler, Singatse Peak Services, LLP - via electronic mail Taurus Massey, Singatse Peak Services, LLP - via electronic mail David Peri, Peri and Sons - via electronic mail John McMillan, CBI - via electronic mail Julian Isham, CBI - via electronic mail Victor Early, Tetra Tech - via electronic mail Colin Lee, Tetra Tech - via electronic mail Ken Greene, CH2M Hill - via electronic mail Peggy Pauly, YCAG-via electronic mail Lyon County Library System Central

~ =

;-

=

3129

115

I 3/

30/1

5

3/31

/15

4/1/

15

4/2/

15

4/3/

15

4/4/

15

4/5/

15

4/6/

15

4/7/

15

4/8/

15

4/9/

15

4/10

/15

4/11

/15

4/12

/15

4/13

/15

4/14

/15

I I I I I l l l l l l l l l l

4/15

/15

l

4/16

/15

l

4/17

/151

4/18

/15

4/19

/15

4/20

/15

4/21

/15

4/22

/15

4/23

/15

4/24

/15

4/25

/15

4/26

/15

4/27

/15

I I I I I I I I I I 4/

28/1

5 I

4/29

/15

N =

=

= l l l l l l l l l l l l l l l l l l l I I I I I I I I I I I I

~ =

=

= I

=-. =

=

=

Flo

w (

gall

ons

per

day

)

QC

=

=

=

.... =

=

=

=

.... N =

=

=

.... ~ =

=

=

.... =-. =

=

= - • ~ .-3

"'C

l e =

C

. ~

~ .... ., "!'j f

,---

.... QC

=

=

= e

<

., r

~ .

-3

(.JI

"'C

l --

.I e

(JCI

=

e:.

C.

-....

e =

=

=

r,,

e ~ ~

.,

II a

.... ....

....

= ~

= ="

;-~

= =

<

(JC

I ~ =

., -

= -

(JCI

e

~ =

r,

,

N =

=

=

=

4130

115

I I

I I

I I

I I

I I

I

>

"'1 .... e ~ "'"""

~

0 <

~ ~ 0 =

Q.

~

.....

0 ~ >

"'C

"'1 .... .....

N =

~

UI

'-'

3/29

/15

3/30

/15

3/31

/15

4/1/

15

4/2/

15

4/3/

15

4/4/

15

4/5/

15

4/6/

15

4/7/

15

4/8/

15

4/9/

15

4/10

/15

4/11

/15

4/12

/15

i::i

4/13

/15

= -

4/14

/15

~

4/15

/15

4/16

/15

4/17

/15

4/18

/15

4/19

/15

4/20

/15

4/21

/15

4/22

/15

4/23

/15

4/24

/15

4/25

/15

4/26

/15

4/27

/15

4/28

/15

4/29

/15

4/30

/15

=

'

N =

=

= I

""' =

=

=

=-. =

=

=

Flo

w (

gall

ons

per

day

) Q

C =

=

=

lo­ =

=

=

=

1--"

N

=

=

=

lo­ ""' =

=

=

lo­ =-. =

=

=

lo­

QC

=

=

= I = rJJ

.., -

NC

I . -

N~

-~~

• !I

Q

-·

= ..,

-

==

= =

~

~ "C

l II

~

lo­

., =

a~

-·

=

= \,C)

= lo-

--"

' ~ =

=

--

.. :.

~ =

;1

r,,

(JC

I ~

I I

~ '

-.-

--, •

-~ S"

- rJJ ~ =- e· ~ .

a -

~ = =- ~ .... .., "!'j S"

i...!_

N =

=

=

=

> ... -· a ~ fll

lt,,. ~

Q

00 .... Q

fll

lt,,.

~

Q =

Q. ~ -· ... ~ .... Q ~ >

~ ... -· .... ~ =

~

Ul

'-"'

3/29

/15

3/30

/15

3/31

/15

4/1/

15

4/2/

15

4/3/

15

4/4/

15

4/5/

15

4/6/

15

4/7/

15

4/8/

15

4/9/

15

4/10

/15

4/11

/15

~

4/12

/15

=

;-4/

13/1

5

4/14

/15

4/15

/15

4/16

/15

4/17

/15

4/18

/15

4/19

/15

4/20

/15

4/21

/15

4/22

/15

4/23

/15

4/24

/15

4/25

/15

4/26

/15

4/27

/15

4/28

/15

4/29

/15

4/30

/15

= -- --

N =

=

=

.a;. =

=

=

~ =

=

=

Flo

w (

gall

ons

per

day

)

QC

=

=

=

.... =

=

=

=

.... N =

=

=

.... .a;. =

=

=

.... ~ =

=

=

.... QC

=

=

= t_'

!'j t_'

!'j <

<

=

=

"Cl

"Cl

= =

..,

.., =

=

-- -· -· = =

= =

""'=

""'=

=

=

= =

Q

. Q

.

n=

l"!

'j l"!

'j

-- = =

~ ~

II II

l,C

=

~ 'J

Q

.... =

....

:a=

(M =

'JQ

=

=

r,,

- - = = r,, =

.., ~ .... .... 'JQ

"C

l a • •

t_'!'j

t_'!'j

<

<

= =

"C

l "C

l =

=

.., ..,

= =

--....

.... =

=

= =

""'=

""'=

=

=

= =

Q

. Q

.

=

n l"!

'j l"!

'j

--

= =

~

~

N =

=

=

=

> ... -· a ~ fll

lt,,. ~

0 ~

~

00

~

<

~

-c

0 ... ~ flllt,

,. -· 0 =

~

0 =

Q. =

~ =

Q. n ~ -0 ~ >

-c ... -· - ~ =

~

Ul

'-'

3/29

/15

3/30

/15

3/31

/15

4/1/

15

4/2/

15

4/3/

15

4/4/

15

4/5/

15

4/6/

15

4/7/

15

4/8/

15

4/9/

15

4/10

/15

4/11

/15

4/12

/15

4/13

/15

i 4/

14/1

5 .... ~

4/15

/15

4/16

/15

4/17

/15

4/18

/15

4/19

/15

4/20

/15

4/21

/15

4/22

/15

4/23

/15

4/24

/15

4/25

/15

4/26

/15

4/27

/15

4/28

/15

4/29

/15

4/30

/15

5/1/

15

App

roxi

mat

e P

on

d D

epth

(fe

et)

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

N

Q ~

N ~ ~ ~ ~ ~ ~ ~

Q ~

N ~ ~ ~ ~ ~ ~ ~

Q

I I

I I I

< 'i

:I 'T

j r

t:J"' ~

>-3 ~

en

~

tTl

......

< -g '"

I ~ o· t:S

'i:

I 0 8.

I I I

<

en

'Tj

r o

~

>-3

.....

en

I 'i:

I -

en

O

L'S

t:S

<

0

.. .g

N

O

'"

I ~ .....

0 t:S

'i:I

0 t:S

0..

to

I I

en

'Tj

en ~

'i:I

en

tTl ~ 0 '"

I ~ .....

0 t:S

'i:I

0 8. n

> ., ... =

~

(llllfo

,.

~

Q

~

~

r.,;.

~

Q =

Q.

r:,.i

~

~ =

r:,.i

Q. =

~

~ ., ~

~ ~ .... r:,.i

>

"'C ., ... .... N =

~

UI

'-._

I

3/29

/15

3/30

/15

3/31

/15

4/1/

15

4/2/

15

4/3/

15

4/4/

15

4/5/

15

4/6/

15

4/7/

15

4/8/

15

4/9/

15

4/10

/15

4/11

/15

4/12

/15

4/13

/15

~ =

4/14

/15

.....

~

4/15

/15

4/16

/15

4/17

/15

4/18

/15

4/19

/15

4/20

/15

4/21

/15

4/22

/15

4/23

/15

4/24

/15

4/25

/15

4/26

/15

4/27

/15

4/28

/15

4/29

/15

4/30

/15

5/1/

15

Rem

aini

ng F

reeb

oar

d (

feet

)

= =

= =

= -

--

--

N

N

N

N

N

~

= N

~

~

~

= N

~

~

~

= N

~

~

~

=

-a

n r-1

I

I

---,

~

I~

'"d

"'1"'.1

.

>

a: >

rJJ.

-"C

"C

""

I 0 .

<

t_'!'j

f'C

Q..

. <

=

"Cl

0

'"rj

""I

f'C

f'C

.

O'

"'I

-0

=

..... .... 0 =

= a

. ""d

.

0 =

=- "'1"'.1

L

"'

I ~

. ~

'c:J'

0 .

= a

. l'-

--J

. I

. . - . . . . . .

,_' - . . .

11,

- . . - I I

I I

I I

I I

I I

I I

l _

J

> ... -· a ~ ""'"

~

Q

~ a: rJl

~

<

~

-c

Q ... ~ ""'" -· Q =

~

Q =

Q.

~

; ~ O'"

Q ~ ... Q.

rJl

""'"

~ ""'" =

1:1.l >

-c ... -· ... ~ =

~

Ul

'-"'

I 2015 Monthly Leak Detector Data I Leak Detector ID1 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Monthly Totals

VLTSP w w w w

3,922 2,770 1,606 3,164 11,462

VLTP1 D D D D

0 0 0 0 0

w w w w VLTD1 25,795

12,920 5,730 4,101 3,044

w w w w VLTD2 4,213

1,124 1,076 1,117 896

VLTD3 D D D D

0 0 0 0 0

D w w w EP"B" 1,242

0 1,200 42 0

EP"C" D D D D

0 0 0 0 0

IFX w w w w

234 91 61 43 39

II FX w w w w

107 38 32 14 23

Ill FX D D D D

0 0 0 0 0

SSP1 D D D D

0 0 0 0 0

SD1 w w w w

8,988 7,138 17,757 22,380 56,263

SD2 D D D D

0 0 0 0 0

SD3 D D D D

0 0 0 0 0

MD1 w w w w

28 21 7 0 0

Total 27,104 18,014 24,680 29,546 0 0 0 0 0 0 0 0 99,344

Notes: 1) Leak Detector Locations shown on Figure 2-1 of the 2010 Annual O&M Report (June 2, 2011)

2) W=Wet; and D = Dry