sunrise mountain landfill 1999 administrative record ... · shin i date i time ho nddate ndt1me i...

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2095949

SUNRISE MOUNTAIN LANDFILL REPAIRCALCULATION NOTEBOOK

Pan 1 Ditches — Hydrology and Runoff Calculations

Pan 2 Ditches — Sizing and Design Calculations

January 26, 1999

Harding Lawson Associates 'Engineering and Environmental Services /5145 South Arville Street, Suite A \(0\Las Vegas. Nevada 89118 — (702) 251-5449 (

PART 1

MEMORANDUM

To:

From:

Date:

Subject:

Project Number:

Joe Milazzo

Joe Rumann

January 7, 1999

Sunrise Landfill

42725.3

This memo summarizes the hydrologic analysis performed for onsite conditions at the Sunrise landfill.The analysis reflects changes to the drainage pattern as a consequence of the flood damages.

The design event is the 25-year frequency as established using Clark County Regional Flood ControlDistrict (CCRFCD) criteria. The watershed boundaries are shown on the enclosed site plan. Watershedareas are scaled approximations. The time of concentration for most subbasins is assumed as 10minutes. The losses are based upon an SCS curve number of 87, as used in previous analyses. Theresults are provided in the attached HEC-1 model output.

If you have any questions please call, thank you.

Ditch

Ditch 1Ditch 2Ditch 3Ditch 4Ditch 5Ditch 6Ditch 7Ditch 8Ditch 9Ditch 10Ditch 11Ditch 12Ditch 13

Q25

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19cfs23cfs38cfs22cfs24cfs59cfs12cfs79cfs

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Harding Lawson AssociatesEngineering and Environmental Services234 North Central Avenue. Suite 600Phoenix, AZ E5004- (602) 252-4105

.ESS::'; -.

..s. i!*r CCSPS or ENGINEERSiv:s:::c:c ENGINEERING CENTER

i09 SECOND STREET

CiViS. CALIFORNIA 9S616

(916) 756-1104

X X XXXXXXX XXXXX

x x x x xX X X X

XXXXXXX XXXX X

X X X X

X X X X X

X X XXXXXXX XXXXX

XXXXX

X

XX

X

X

X

X

xxx

THIS r?CISAM ?E?LACES AL. SS£V::LS .E3SICNS CF H E C - * <MOUN AS HEC1 (JAN 73), HEC15S, !is":3. AND HEC1KW.

THE DEF:NJT::NS OF VARIABLES -?TIM?- AND -PTICR- HAVE CHANGED FROM THOSE USED UITH THE 1573-siYLE INPUT sTau:7«THE DEFIN1TICN DF -AHSKK- CN RN-CA33 WAS CHANGED UITH REVISIONS DATED 28 SEP 81. THIS IS THE -ORTRAN77 VERS!CN

NEW OPTIONS: DAHBREAIC OUTFLOW SUBf.ESGENCE , SINGLE EVENT DAMAGE CALCULATION, OSS:URITE STAGE FREQUENCY,

DSS:READ TIME SERIES AT DESIRED CALCULATION INTERVAL LOSS RATE:GREEN AND AHPT INFILTRATICK

KINEMATIC WAVE: NEU FINITE DIFFERENCE ALGORITHM

nEC-1 INPUT PAGE

.::AC

= 3

:;

i;

;;

s;

• '.

;;r 1

91

«

£

.S'.2

«3A

PR

LSUD

KKBAPRLSL'D

KKBAPR

LSuo

KKBA

PR

LSUD

KKBAPR

LSUO

: 223

2.:l

.~2 .:n .3:3 .:u .321 .3163 3 .303 .007 .C32 .OC6

.337 .::: .001 .001 .:cs .01

.::5 .;•.. .::a .:o3 .302 .012

.C91 .:i .334 .037 .331 .007

.338 .:CS .312 .022 .316 .311

.003 .302 .302 .001 .003 0

.301 .33:

AREA1

i

37*» •V . 1

ASEA2

.0321

870.2

AREA3

.049

187

0.2

AREA4

,0144

1

87.1

AREAS

.0064

1

870,1

AREA7

.014

187

0.15

.3C4 0

.31 .014 .OC9

.315 .012 .008

.327 .03 .357

.3*5 .316 .035

.3:3 .02 .006

.301 .001 .303

7

8

9

13 =: .307 .332 .301 .001 .303 .01 .015 .012 .008 .332

16

17

18

"9

20

2122232425

2627282930

3132333435

3637383940

41

42

43

44

45

336

0

*EC-1 [".PUT 'AGE I

52

•A

53Si

5556

5758596061

6263

6465666768

6970717273

7475

7677787980

818283848586

«:A

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.3

<:<:A

39

.5_;

«

'••'-

«BAPRLSUD

KK

BA

PR

LSL'D

KKHC

KKBAPRLSUO

KKBAPRLSUDZZ

AREAS

.313

.10

AREA90.013

1

0.1

SAN09

'AREAVO

.021

0.1

AREA13.014

1

.1

8910133

AREA11.063

1

.25

AREA12.01

1

.1

= 7

J7

87

87

87

87

>.:. : .i CONNECT:?

;•- • > ? siv-;-::1; cs =_-><o s-.:.

:<•••; ?£'.-'. :; ::VJ?TH: cs =.•'=;:

3 =

53

57

64

81

ASeAj

RUNOFF ALSO COMPUTED AT THIS LOCATION

SANS?

AREA?

AREA6

AREAS

8AND9.

891013.

AREA9

AREA10

AREA11

AREA13

AREA12

:.:cc J.S. ASMY CORPS OF EHCISEE3S

•iTDRCLOGlC ENGINEERING :HSTE=

509 SECOND STREET

5AV1S, CALIFORNIA ?:i'6

(916) 756-110i

SUNRISE ;.A>.::

25 YEAR £,:'•

OMSITE ::S:

CUT?UT ::NTROL VARIABLES

CSCAL 0.

=?:'.: :CNTROL='.:• ::«TflCL-VC'.CGRAPH PLOT SCALE

TIME OATA FOR INPUT T'.HE Si-IEE.XMIH 5 ::VE INTERVAL IV MINUTESJX:ATE : 3 S-I;T:MG CATEJXTIME G £-.;STiNG T!«E

IT HTORCGRAPH TIKE DATASHIN

I DATEI TIME

HONDDATENDT1MEI CENT

51 00000

2881 0

235519

«I«JTES IN COMPUTATION INTERVALSTARTING DATESTARTING TIME

ML'MBER OF HYDROGRAPH CRD1NATESESS ING DATEESD1NG TIMECEKTURY MARK

COMPUTATION INTERVALTOTAL TIME BASE

.C8 HOURSJ3.9Z HOURS

ENGLISH UNITSDRAINAGE AREAPRECIPITATION DEPTHLENGTH, ELEVATIONFLOWSTORAGE VOLUMESURFACE AREATEMPERATURE

SQUARE MILESINCHESFEETCUBIC FEET PER SECONDACRE-FEETACRESDEGREES FAHRENHEIT

16 « AREA1

SJBBASIN SLNCfF

•:=.-*

.3: I'.ITIAl ABSTRACTION

S7.:: :.'SVH SLMSES

scs D^'-ssiCMsSS JNIT:SA?H"'.AS * *C L.AC

?SEC:PITAT: ;N STATION O A T A

•TATICN TOTAL AVC. AMNUAL

i 2.53 .:o

L :!STS!E'JT1CNS

STATION

.02

.03

.01

.00

.09

.01

.CO

.00

1, WEIGHT * \00.Oi

.00

.00

.01

.12

.01

.00

.00

.01

.00

.00

.01

.03

.01

.00

.02

.01

.00

.00

.04

.02

.00

.:2

.CO

.CO

.30

.03

.02

.00

.02

.01

.01

.01

.01

.01

.00

.01

.01

.02

.03

.02

.01

.00

.00

.01

.01

.03

.02

.02

.00

.00

.01

.01

.06

.00

.01

.00

.CO

.01

.00

.09

.00

.01

.00

20. 30. 13.

UNIT HTDROGSAPH

a ENO-of-PsaioD ORDINATES2. 1. o.

21 KK

*•*******•**•*

• •

• AREA2 *• *••*******•*•*•

SUBBASIN RUVOFF OATA

'•> 5A SUBBASIN CHARACTERISTICSTARE* .03 SUBBASIN AREA

PRECIPITATION DATA

23 PR RECORD I«C STATIONS 1

-EIGHTS

::s LCSS .Ai-

rs''.

57;y? .:: ==—-s- :«PERVICUS ASEA

S:S C^iNSIC'iLisS '-'\:";A:-

BR-C'.PITATICN STATION 3ATA

STATION

1

57 A L

TEHPCJAI OlSTRIBUTICNS

STATION

.02

.31

.CO

.01

.00

.04

.00

.00

.12

.ci

.00

.00

.02

.01

.CO

.02

.00

.02

.01

.01

.01

.31

.01

.00

.31

.01

.32,!3.02.01.CO

.CO

.01

.01

.03

.22

.02

.00

0

"

16

2«

:o

.00

.31

.CO

.C9

.CO

.01

.CO

16.

1.

51.1.

64.

0.

51.

0.

UNIT HYOROGRAPH

u END-OF-PERIOO ORDINATES28. 16. 9.

26 KK AREAS

SU8BA51N RUNOFF DATA

27 BA SUBBASIK CHARACTERISTICS

TASEA .05 SUBBASIM AREA

PRECIPITATION DATA

28 PR0 PU

RECORDIHG STATIONS 1

WEIGHTS 1.00

-v LS SCS LOSS KATE

STRTL

CltVNBR

RTIHP

.30 1NIT.IAL ABSTRACTION

87.00 CURVE NUMBER

.00 PERCENT IMPERVIOUS AREA

SCS CI^ESSIONLESS UNITGSAPH

TEMPORAL ;:sTs:ir.::c\5

STATICS '., WEIGHT t

2 .4 .:: .323 . 5 .33 .01

.3 .33 .30

3 .01 .31 .00

? .12 .33 .34

.31 .01 .02

3 .00 .33 .30

33 .CC

.32

.30

.33

.30

.33

.32

.30

.02

.01

.01

.01

.01

.01

.00

.31

.31

.32

.33

.32

.01

.CO

.33

.01

.3*

.33

.C2

.C2

.00

.33

.3'

.31

.36

.30

.01

.00

.33

. •»•"

.33

. 3?

.33

.01

.33

UNIT HYORCGRAPH

£>JD-0--s=?ICO CS01NATES

i3. 25. U.1.

31 KK AREAi

SUBBASIN RUNOFF DATA

32 BA SUBBASIN CHARACTERISTICS

TAREA .01 SUBBASIH AREA

PRECIPITATION DATA

33 PR0 PU

RECORDING STATIONS 1

WEIGHTS 1.00

34 IS SCS LOSS RATE

STRTL

CRVKBR

RTIHP

.30 INITIAL ABSTRACTION

87.00 CURVE NUMBER.00 PERCENT IMPERVIOUS AREA

35 UO SCS DIMENSIONLESS UNITGRAPH

TLAG .10 LAG

PRECIPITATION STATION DATA

S T A T I C S "3TAL

- :•;ANNUAL -E15XT

.co

^ M

^

i

2

1C

. zc,:o.:s.C2

••t*i f W

.C',

.01<* •

.01

.CO

.'.2

.33

.C2

.01

.00

.C'i

.03

.C2

.02fl^

.:i .cc.Co .09.CO .CC

.01 .01

.CO .03

12.

'.MIT -T3ROGRAPH

:ND-OF-Pr51CC CRDINATES

3. '. C.

34

SUE6ASIN RUNOFF DATA

37 BA SUBBASIN CHARACTERISTICS

TAREA .01 SUBBASIN AREA

PRECIPITATION DATA

38 PR0 PU

RECORDING STATIONS 1

WEIGHTS 1.00

39 IS SCS LOSS RATE

STRTL .30 INITIAL ABSTRACTION

CRVNBR 87.00 CURVE NUMBER

RTIHP .00 PERCENT IMPERVIOUS AREA

40 UO SCS OtMENSIONLESS UN ITGRAPH

TUG .10 LAC


STATION TOTAL AVG. ANNUAL WEIGHT

1 2.S3 .00 1.00

TEMPORAL DISTRIBUTIONS

STATION

.02

.00

1, WEIGHT

.04

.00

,.;

» 1.00

.01

.00

-

.02

.01

.02

.00.02.01

-••-••..'«'«. ,c.

.01

.01.00

.01

.00

.01

.00

.01

•- '. Bui • ' -vJ»J£.' '.•'••» Vtij'i.'.'VAt •̂Mj'lisa*: >«•/.-.-

.31(** *

• >* <

.01

.01

.:2 .:

.:s .:

*» •

- *

>i *t >

^ t

«

3

.3;

.36

.33

.33

.3

HYCRC3SAPH

-?rs;c: CROINATES•. c.

:*; S'.NCFf DATA

.2 5A SU83AS:s CHARACTER 1ST ICS

-A?£A .01 SJ53AS1N AS=A

?REC:?::ATION DATA

; PRo PU

RECCSDIMC STATIONS 1

WEIGHTS 1.00

LS SCS LCSS RATE


CSVKBR 87.00 CURVE NUMBER

RTIHP .00 PERCENT IMPERVIOUS AREA

45 UO SCS DIMEHSIONLESS UNITCRAPH

TLAG .15 LAC


STATION TOTAL1 2.53

AVG. ANNUAL

.00

WEIGHT1.00


STATION

.02

.00

.01

.00

.09

.01

.00

.00

1, WEIGHT = 1.00

.04

.00

.00

.01

.12

.01

.00

.00

.01

.00

.00

.01

.03

.01

.00

.02

.01

.00

.00

.06

.02

.00

.02

.00

.00

.00

.03

.02

.00

.02

.01

.01

.01

.01

.01 '

.00

.01

.01

.02

.03

.02

.01

.00

.00

.01

.01

.03

.02

•02.00

.00

.01

.01

,06

.00

.01

.00

.00

.01

.00

.09

.00

.01

.00

UNIT XYDROGRAPH

:• END-OF'PER ICO CROINATES!. -. 2.

.6 « * 5ANC7

l MJMSSS of HYORCSSAPHS 'z CCMBINE

i8 KK AREA6

SUBBASIN R'JNOFF DATA

49 8 A, SUBBAStN CHARACTERISTICS

TAREA .02 SUBBAS1N AREA

PRECIPITATION DATA

SO PR

0 PU

RECCRDING STATIONS 1WEIGHTS 1.00

51 LS SCS LOSS RATESTRTLCAVNBRRTIKP

.30 INITIAL ABSTRACTION87.00 CURVE NUMBER


52 UO SCS DIHENSIONLESS UNITGRAPH

TUC .10 LAG


STATION TOTAL AVG. ANNUAL WEIGHT1 2.53 .00 1.00


STATICK 1, WEIGHT > 1.00

.02 .04 .01 .02 .02 .02 .01 .00 .00 .00

.01

01

.01

.31

3 £%:•:= •=«.::: CSDINATES23.

5- EA S rJE£AS!'» CHARACTERISTICS

.01 £U3:AS;N AREA

PSECIPTATICN DATA

0 PT

0 PU

TOTAL STCSH STATIONS 1WEIGHTS 1.00

50 PR0 PU

RECORD I KG STATIONS 1WEIGHTS 1.00

55 IS SCS LCSS RATE

ST8TLCRVliBRRTIHP


87.00 CURVE NUMBER.00 PERCENT IMPERVIOUS AREA

56 UO SCS OIHENSICNLESS UN1TGRAPH

TLAG .10 LAG


STATION

1

TOTAL2.53

AVG. ANNUAL

.00

WEIGHT

1.00


STATIC*

.02

.00

.01

.00

.09

.01

1. WEIGHT « 1.00

.04

.00

.00

.01

.12

.01

.01

.00

.00

.01

.03

.01

.02

.01

.00

.00

.04

.02

.02

.00

.00

.00

.03

.02

.02

.01 -

.01

.01

.01

.01

.01

.01

.02

.03

.62

.01

.00

.01

.01

.03

.02

.02

.00

.01

.01

.06

.00

.01

.00

.01

.00

.09

.00

.01

.00 .00 .00

.SI" j yC

2 :s;-of-s£r O R S I N A T E S0 .

AREA;

suBBAs:>i CHA.02 r.'HHASIN AREA

59 F3

0 f'J

STATIWSU E - C H T S

*>0 IS SCS LOSS 5iTSTSr.

CRVS3SRTIMP

.30 INITIAL ABSTRACTION87.00 CURVE NUMBER


61 US SCS DIMENSICNIESS UNITGSAPH

TUG .10 LAS


STATION TOTAL

1 2.53AVC. ANNUAL

.00

WEIGHT1.00


STATION

.02

.00

.01

.00

.09

.01

.00

.00

1, WEIGHT * 1.00

.04

.00

.00

.01

.12

.01

.00

.00

.01

.00

.00

.01

.03

.01

.00

.02

.01

.00

.00

.04

.02

.00

.02

.00

.00

.00

.03

.02

.00

.02

.01

.01

.01

.01

.01

.00

.01

.01

.02

.03

.02

.01

.00

.00

.01

.01

.03

.02

.02

.00

.00

.01

.01

.06

.00

.01

.00

t

.00

.01

.00

.09

.00

.01

.00

39. 55. 26. 10.

UNIT HYDROGRAPH

8 EKD-OF-PERJCD ORDINATES

4. 1. 1. 0.

65 EA SUSEAS:\ CHARACTERISTICS

TAS-A .02 SU35ASIN AREA

PRECIPITATION DATA

66 PR0 PU

RECEDING STATIONS 1

WEIGHTS 1.00

67 IS SCS LOSS RATE



RTIMP .00 PERCENT IMPERVIOUS AREA

68 UO SCS DIHENSIONLESS UHITCRAPH

TLAC .10 LAG


STATION TOTAL

1 2.53AVC. ANNUAL

.00

WEIGHT

1.00


STATION

.02

.CO

.01

.00

.09

.01

1, WEIGHT * 1.00

.04

.00

.00

.01

.12

.01

.01

.00

.CO

.01

.03

.01

.02

.01

.00

.00

.04

.02

.02

.00

.00

.00

.03

.02

.02

.01 -

.01

.01

.01

.01

.01

.01

.02

.03

.02

.01

.00

.01

.01

.03

.02

.02

.00

.01

.01

.06

.00

.01

.00

.01

.00

.09

.00

.01

.CO

."JIT '-i'CSOSRAPH

s? « ASEAl i

S'J2SAS;s V.SC" DATA

.C1 E-lsSASIN AREA

0 PU

'2 LS SCS LCSS

STRT'.

CRVK3R

RT1MP

S*ATICNS^EIGHTS '.00


87.00 CJRVE NUMBER

.00 PHHCEST IMPERVIOUS AREA

73 UO SCS D1KEMSIONLESS UNITGSAPH

TLAC .10 LAC


STATION

1

TOTAL

2.53

AVG. ANNUAL

.00

WEIGHT

1.00


STATION

.02

.00

.01

.00

.09

.01

.00

.00

1, WEIGHT = 1 . 0 0

.04

.00

.00

.01

.12

.01

.00

.00

.01

.00

.00

.01

.03

.01

.00

.02

.01

.00

.00

.04

.02

.00

.02

.00

.00

.00

.03

.02

.00

.02

.01

.01

.01

.01

.01

.00

.01

.01

.02•03.02.01.00

.00

.01

.01

.03

.02

.02

.00

.00

.01

.01

.06

.00

.01

.00

.00

.01

.00

.09

.00

.01

.00

31. 45. 20. 8.

UNIT HYDROCRAPH

8 END-OF-PERIOO OROINATES

3. 1. 0.

..JT.. ..Nl J.-.'JU.J.JJT

SAJ£V'{<C'V-

^ " :CMBINE

« ASEAT-

suBBASii V.MQFF DATA

77 BA :^ CHARACTERISTICSTiSEA .06 SUB3ASIN AREA

PRECIPITATION DATA

78 PR0 PU

RECCS5INC STATIONS 1

WEIGHTS 1.CO

79 LS SCS LCSS RATH

STJTL .30 INITIAL ABSTRACTION


RT1HP .00 PERCENT IMPERVIOUS AREA

80 UD SCS DIHENSIONLESS UNITCRAPH

TLAG .25 LAG

P R E C I P I T A T I O N STATION DATA

STATION1

TOTAL2.53

AVG. ANNUAL

.00

WEIGHT1.00

TEMPORAL D I S T R I B U T I O N S

STATION

.02

.00

.01

.00

.C9

.01

1, WEIGHT > 1.00

.04

.00

.00

.01

.12

.01

.01

.00

.00

.01

.03

.01

.02

.01

.00

.00

.04

.02

.02

.00

.00

.00

.03

.02

.02,01 ..01

.01

.01

.01

.01

.01

.02

.03

.02

.01

.00

.01

.01

.03

.02

.02

'.00

.01

.01

.06

.00

.01

.00

.01

.00

.09

.00

.01

.:3 .co .CO .CO .50 .SO

•a .7

5 . 1.

AHEA',2

SUBBASIS r-^QFr DATA

32 3A SUBBAS:s CHARACTERISTICSTASEA .01 S.-S=AS;N AREA

::A::CS CATA

83 P^0 rU

RECCS3ISG STATJCIS

WEIGHTS

'. IS SCS LCSS RATE

Sim .30 INITIAL ABSTRACTION

CSVN8R 87.00 CLttV: NUMBER

RTIHP .00 PS5CHNT IMPERVIOUS A«£A

65 SCS DIMENSIONIESS UN1TCRAPH

TLAG .10 LAC


STATION TOTAL AVG. ANNUAL WEIGHT

1 2.53 .00 1.00


STATION

.02

.00

.01

.00

.09

.01

.00

.00

1, WEIGHT > 1,00

.04

.00

.00

.01

.12

.01

.00

.00

.01

.00

.00

.01

.03

.01

.00

.02

.01

.00

.00

.04

.02

.00

.02

.00

.00

.00

.03

.02

.00

.02

.01

.01

.01

.01

.01

.00

.01

.01

.02

.03

.02

.01

.00

.00

.01

.01

.03

.02

.02

.00

.00

.01

.01

.06

.00

.01

.00

.00

.01

.00

.09

.00

.01.00

22. 32. H. 6.

UNIT HTOROGRAPH

& ENO-QF-PERIQD OROINATES

2. 1. 0.

'^AXiHL'M :;«;

STAGE '-"AX ;'

•"»«C3«?- A: :;-A. -3. 3.i: 2.

lYDRCGSAPH A" :?M5 3. 3.5C '. 0.

MYORC5RAPH AT J?iA7 '&. 3.53 -. 1.

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PART 2

CurvePlotted Curves for Circular Channel

Project DescriptionProject F3eWortsheetPlow ElementMethodSorve for

c:\haettitfJmw\aunrtse.fm2MetalCircular ChannelManning's FonnulaDischarge

Constant DataManning* Coefficient 0.024Channel Shx>e 0.100000 ft/ft

Input DataMMmum Maximum Increment

DepthDiameter

0.6018.00

1.5036.00

0.50 n6.00 in

60.0

55.0

50.0

45.0

40.0

| 35.0

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?"25.0

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Discharge vs Depth varying Diametero se.om-t- 30.0 inA 24.0nQ 18.0 h

5 O.6 0.7 O.B O.9 1.0 1.1 1.2 1.3 1.4Depth (ft)

ca/ia/ae•.Inc. 37 BnoetaMta Ro«a VSrttoftoury. CT 08706 (ZO) TK-tOOC

18" CMPWorksheet for Circular Channel

Project DescriptionProject FileWorksheetFlow ElementMethodSolve For

c:\haestaa\fmw\sunnse.lm2MetalCircular ChannelManning's FormulaDischarge

input DataMannings CoefficientChannel SlopeDepthDiameter

0.0240.100000 ft/ft0.75 ft

18.00 in

ResultsDischargeFlow AreaWetted PerimeterTop WidthCritical DepthPercent FullCritical SlopeVelocityVelocity HeadSpecific EnergyFroude NumberMaximum DischargeFull Flow CapacityFull Flow SlopeFlow is supercritical.

9.00 cfs0.88 ft1

2.36 ft1.50 ft1.16 ft

50.000.028037 ft/ft

10.18 ft/s1.61 ft2.36 ft2.34

19.35 cfs17.99 cfs

0.025000 ft/ft

02/18/9903:10 03PM HMIUH M«thoa». Inc. 37 BroowBe Road Wweitwry. CT 06708 (203)755-1668

FtowMutBf v5.13P*0e 1 el 1


Project DescriptionProject FileWorksheetFlow ElementMethoaSolve For

c:\haestaa\fmw\sunnse.rm2MetalCircular ChannelManning's FormulaDischarge

Input DataMannings CoefficientChannel SlopeDepthDiameter

0.0240.100000 ft/ft1.00 ft

24.00 in

ResultsDischargeFlow AreaWetted PerimeterTop WidthCritical DepthPercent FullCritical SlopeVelocityVelocity HeadSpecific EnergyFroude NumberMaximum DischargeFull Flow CapacityFull Flow SlopeRow is supercritical.

19.37 cfs —1.57 ft*3.14 ft2.00 ft1.5B ft

50.000.026737 ft/ft

12.33 ft/s2.36 ft3.36 ft2.45

41.68 cfs38.75 cfs0.025000 ft/ft

02/11/9903:09:36 PM HaMUd Mtftous. Inc. 37 Brook»We Ro»d Watertjury. CT 0670» (203) 755-1666

vS.13ef 1



c:\haestaa\lmw\sunnse.fm2MetalCircular ChannelManning's FormulaDischarae


0.0240.1 ooooo ft/ft1.25 ft

30.00 in

ResultsDischargeFlow AreaWetted PerimeterTop WidthCritical DepthPercent FullCritical SlopeVelocityVelocity HeadSpecific EnergyFroude NumberMaximum DischargeFull Row CapacityFull Flow SlopeFlow is supercritical.

35.13 cfs2.45 ft*3.93 ft2.50 ft2.01 ft

50.000.025646 ft/ft

14.31 ft/83.18 ft4.43 ft2.55

75.57 cfs70.25 cfs

0.025000 ft/ft

02/16/9903:09:18PM Hwitad M«thou. Inc. 37 Breoksxto Road Witertury, CT 06708 (203)755-1606

FtowMaster vi.13P*0eteM



c:\haestad\fmw\sunnse.lm2MetalCircular ChannelManning's FormulaDischarge

Input DataMannings CoefficientChannel SlopeDepthDiameter

0.0240.100000 ft/ft1.50 ft

36.00 in

ResultsDischargeFlow AreaWetted PerimeterTop WidthCritical DepthPercent FullCritical SlopeVelocityVelocity HeadSpecific EnergyFroude NumberMaximum DischargeFull Flow CapacityFull Flow SlopeFlow is supercritical.

57.12 cfs3.53 ft*4.71 ft3.00 ft2.45 ft

50.000.025191 ft/ft

16.16 ft/s4.06 ft5.56 ft2.63

122.89 cfs114.24 cfs

0.025000 ft/ft

02/18/9903:08.47 PM Ha»iud Malhoas. Ine 37 Brookslda Road Wawmury, CT 06708 (203)755-1668

FtowM»ter vS.13P»fl»1of1

CurvePlotted Curves for Circular Channel

Project DesmuOunProject ReWorksheetFtowBememMethodSolve For

c:>hae>tad\fmwS*ini*e.frn2concreteCircular ChannelManning's FomtulaDischarge

Constant DataManning* Coefficient 0.013Channel Siooe 0.100000 fbtt

Input DataMinimum Maximum Increment

DepthDiameter

0.5018.00

1.5036.00

0.50 ft6.00 In

0C

110.0

1OO.O

9O.O

so.o

70.0t)

60.0

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4O.O

30.0

20.0

10.O

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Dbcharge v» Depth varying DiameterO 36.0 in+ 30.0 inA 24JOinQ 18.0 (n

0.5 0.6 0.7 0.6 O.9 1.O 1.1Depth (ft)

1.2 1.3 1.4

ccnase02:42.10 PM HM«tad MMhad*. Inc. 37 BraotaidB ftoad Wctartwry. CT 00706 (203)75B-1« 10M

CMP @ .01Worksheet for Circular Channel

Protect DescriptionProjectFiieWorksheetFlow ElementMethodSolve For

c:\riaestaa\fmw\sunrtse.fm2MetalCircular ChannelManning's FormulaDischarge


0.0240.010000 ft/ft2.75 ft

66.00 in

ResultsDischargeFlow AreaWetted PerimeterTop WidthCritical DepthPercent FullCritical SlopeVelocityVelocity HeadSpecific EnergyFroude NumberMaximum DischargeFull Flow CapacityFull Flow SlopeFlow is subcntical.

90.94 cfs11.88 ft1

8.64 ft5.50 ft2.63 ft

50.000.011650 ft/ft7.66 ft/s0.91 ft3.66 ft0.92

195.66 cfs181.89 cfs

0.002500 ft/ft

02/18/9903:18:17 PM H«MUd Mtthodt, me. 37 Breokrtlt ROM Wttwtwy. CT 06700 (203)755-1660

vS.131 oM

CLARK COUNTY HEALTH DISTRICT

P.O. BOX 39O2 • 623 SHADOW LANE - LAS V E G A S . N E V A D A 8 9 1 2 7 • 7 0 2 - 3 8 3 - 1 2 7 6 • FAX 702 -383 -1443

July 10, 1998

Clark County Public WorksMr. Martin Manning, P.E., Director500 South Grand Central ParkwayLas Vegas, Nevada 89155-4000

Republic D.U.M.P. Co.Mr. Stephen Kalish, President770 East Sahara AvenueLas Vegas, Nevada 89104

Gentlemen:

Based upon recent inspections of the closed Sunrise Landfill, the Clark CountyHealth District has determined that past storm events have eroded the cover of alandfill cell located within a portion of SW1/4, SE1/4, Section 1, T21S, R62E,M.D.M., Nevada, that was filled by D.U.M.P. Co. around 1979 or 1980.Construction debris, including asbestos containing transite pipe and siding materialwere found to have migrated approximately 200 yards westerly down a wash intoadjacent BLM property within a portion of SE1/4, SW1/4 of Section 1.

Ten (10) samples of suspected asbestos-containing debris were taken by ClarkCounty Health District staff on June 16, 1998 and the asbestos content resultswere received on June 25, 1998. Seven (7) of these samples were shown tocontain 20% asbestos. Health District representatives met with D.U.M.P-Co.representatives at the site to review the findings on July 6 1998.

CLARK COUNTY • LAS VEGAS • NORTH LAS VEGAS • BOULDER CITY • HENDERSO


In an effort to remediate this situation, Clark County Public Works and RepublicD.U.M.P. Co. are to:

1. Immediately contract with an asbestos consultant, licensed by the NevadaOccupational Safety and Health Enforcement Section to develop a work planto remediate the affected area employing all applicable Occupational Safetyand Health Association standards.

2. Submit the work plan within five (5) days receipt of this letter.

3. Immediately following approval by the Clark County Health District of thework plan, manually remove all construction debris including asbestoscontaining materials from the affected site, and place it in proper disposalareas of the Apex landfill.

4. In addition, the recipients of this letter shall within thirty (30) days of receipt,contract with a Nevada registered professional engineer to review the currentclosure plan, and offer recommendations to modify the drainage plan toprevent further erosion at this landfill cell. These recommendations shall besubmitted for approved by the Clark County Health District within thirty (30)days of start of contract.

5. Provide monthly progress reports commencing August 1 until January 1,1999.

If there are any questions, please contact Edmund Wojcik at 383-1256 or HaroldGlasser at 383-1276.


Sincerely,

Edmund J. Wojcik, P. E.Environmental Health Engineer/ManagerEnvironmental Health Division

Harold P. GlasserEnforcement SupervisorAir Pollution Control Division

/smb

cc: David Emme, NDEPDoug Zimmerman, NDEPBLM - Mr. Mike Dwyer, District Manager

Office of the County Manager500 S Grind Cantrt) Pky 6th F1 • POBax £51111 • Ln Vegas NV 89155-1111

(702)455-9530 • Fax (702) 465-3 5 SB

Dale W. Aitcaw. County Manager • Michael R. Alastuey, AMiram County Manager • Kchara B Holmes, Auvunt County Manager

March 1U 1999

Allen Biaggi, AdministratorDepartment of Conservation and Natural ResourcesDivision of Environmental Protection333 W.Nye Lane, Room 138Carson City, Nevada 89706-085 1

Dear Mr. Biaggi:

As indicated in our last correspondence dated January 27, 1999, the County is committed toenvironmental protection and complying with all environmental issues and regulations at SunriseLandfill. To accelerate progress, in late 1998, the County Manager's Office designated theDepartment of Comprehensive Planning, Environmental Division, as the County's lead agencyfor resolution of environmental issues associated with Sunrise Landfill. The EnvironmentalPlanning Division already has responsibility for air and water quality planning for the Countyand has expertise to address similar issues at Sunrise Landfill. All future documents submitted toregulatory agencies, regarding Sunrise Landfill will be submitted by Clark County and not itsoperators or consultants.

THE COUNTY'S TEAMThe importance of the Sunrise Landfill project has demanded that additional County resources beassigned to address the environmental issues. Not only are Comprehensive Planning and PublicWorks leading the effort, they also have support and resources from the County Manager'sOffice. County resources currently assisting on the Sunrise Landfill project include:

Richard Holmes, Assistant County ManagerVictor Priebe, Chief Deputy District AttorneyJohn Schlegel, Director of Comprehensive PlanningMartin Manning, Director of Public WorksChristine Robinson, Environmental Planning Division ManagerCharles Jenner, Environmental & Neighborhood Services Division Manager

Additional personnel includes one full-time staff person solely dedicated to the project, two pan-rime staff persons, an environmental consultant, and legal counsel specializing in solid wasteregulatory' compliance such as RCRA, CERCLA, etc. The name of the environmental consultant

BOMO OF COUNTY (MUCC L WOOOBUflr Cn*m«n . CAM OMft.

r*OM« ATOMON OATtl • MftO MUROM • MART i KMCMO > LAN6Z M MM.ONC • WTWiA WUWMt

who has been hired is Gary Johnson, Mine Reclamation Corporation of southern California. Mr.Johnson specializing in environmental analysis, landfill design and permitting, operational plans,construction, and closure compliance. The law firm, Bruen & Gordon, of Walnut Creek,California, is prepared to assist us to meeting regulatory compliance. Bruen &. Gordon is ahighly specialized law firm practicing predominately in the area of regulatory permitting, andenvironmental compliance.

RECENT ACTIONSOver the last few months, the Environmental Planning Division has reviewed the historical files,made a site visit, and has met with all involved agencies such as: NDEP, Clark County HealthDistrict, Bureau of Land Management and Republic Silver State Disposal Service. As part of ourcomprehensive approach to address all environmental issues of the Sunrise Landfill, GaryJohnson (Mine Reclamation Corporation) has been assigned to advise us on action for the northand east off-lease trespass areas, black lagoons, stormwater management, groundwatermonitoring, gas collection systems and landfill cover.

Off-Lease Trespasi AreasIn the north and east off-lease trespass areas, the County is in the process of estimating thevolume of solid waste within the trespass areas through field surveys and areal photointerpretation. From this estimate, costs, remedial approach and schedule can be determined forenvironmental compliance.

Stonnwater Management and Groundwater MonitoringAlthough stormwater management and groundwater monitoring are included in thecomprehensive approach, as previously mentioned, current steps have already been taken toaddress these issues. A modified storm water management plan has been prepared by RepublicSilver State Disposal (RSSD). Complete plans, specifications and a schedule have beensubmitted to the Nevada Division of Environmental Protection (NDEP), Clark County PublicWorks, and Clark County Health District (CCHD) on February 19,1999 for review. In addition,a revised Groundwater Monitoring Plan, as discussed and agreed upon by Clark County, RSSD,and NDEP at a meeting on January 21,1999, was submitted to NDEP on February 11,1999.Preliminary comments from NDEP indicate that with rrir)™ drilling technique modifications, thegroundwater monitoring plan will be accepted. RSSD has committed to implementing this planwithin 30 days of approval, assuming no unforseen complications occur. Acceptance andimplementation of the Stonnwater management plan has not yet been determined. But, the plan,as submitted, could begin being implemented immediately with an estimated completion date ofthree months, per RSSD.

Methane Gas CollectionDesert Research Institute (DRI) of Las Vegas has been awarded $100,000 from the Departmentof Energy (DOE) to conduct a field investigation and validate the possibility of economic use ofthe gases of Sunrise Landfill. Included in the scope of work is tht determination of rate ofmethane release, prediction of the resource life of the methane, and determination of gasextraction-energy generation as a positive remediation strategy. In /use-July, DRI wiJJ conduct asurface air-quality survey to determine if surface emissions have changed since a similar study

03:0788 Pfoa-ClifkCtyCoaprininiPlannini *7Q23tSmO T-ilE P.04/04 F-74T

conducted in 199S and to identify hot-spots for subsurface characterization. In July, thesubsurface survey shall be completed with results to be incorporated into the gas generationmodel. A draft report with detailed findings will be delivered to DOE ai the end of September1999. This preliminary study will aid the County in addressing Clean Air Act requirements. TheCounty has had discussions with CCHD regarding comments to new EPA aii regulations for>rrtfiii« end cost estimates for regulation compliance of Sunrise Landfill.

FUNDINGA critical next step is for County staff to make rscommenaationa to our elected officials, to gaintheir feedback and to identify funding sources for a comprehensive approach to theenvironmental issues of Sunrise Landfill. The funding mechanisms may include one. but morelikely, many sources. The tentative completion date for decisions on funding issues is April 30,1999.

I would like to reiterate our commitment to finding solutions for both short- and long-termenvironmental issues at the Sunrise Landfill. As discussed with Dave Emme, at our March 4thmeeting, the County is prepared and would like to go forward with an agreement between ClarkCounty and NDEP that would address responsibilities, commitments and resolutions. Thisagreement would formally memorialize the County's commitment to issue resolution. TheCounty firmly believes that environmental concerns are community related matters to beaddressed in partnership with our operators, state and local regulators, and the appropriate federalagencies, and we look forward to working with all agencies.

If you have any additional questions or concerns regarding the County's plans to resolve thesemarten, please contact me or Chris Robinson, Environmental Planning Manager at (702) 455-3536.

Sincerely,

Richard B. HolmesAssistant County Manager

cc: John Schlegel, Comprehensive PlanningMJ. Manning, Public WorksChristine Robinson, Comprehensive Planning

STATE OF NEVADAC MORROS. Otrenor KtNNY C. CUINN

Coctntor•LLiN •UCCL A4m**trt*r

1,7516*70670 VgfttfcPw Con*** ArtoraAggr^gQW Federal F«eil.oei

TOO W74678 CP -^g-Lol

Vlmmuirwon TOJ HEOT AirQwhlr• Pollution Contni V^T bS?y

'-5456 XjggSX FtaHKilt 6S7-6J96

DEPARTMENT OF CONSERVATION AND NATURAL RESOURCES

DIVISION OF ENVIRONMENTAL PROTECTION333 W. Nyt Lane, Room 138

Carton City. Nevada 89706*851

March 11, 1999

Richard Holmes, Assistant County ManagerOffice of the County ManagerP.O. BoxSSllllLas Vegas, NV 89155-1 111

RE: Sunrise Landfill Ground Water Monitoring Plan

Dear Mr. Holmes:

On February 11, 1999, NDEP received a Ground Water Monitoring Plan for the SunriseLandfill. This plan was submitted by Gregory Walch on behalf of Republic Silver StateDisposal (RSSD). If a technical issue regarding the drilling and logging technique (describedin more detail on the attachment) is addressed, NDEP finds the plan adequate to providebaseline monitoring information at the Sunrise Landfill in the near term. Our intention is toinclude longer term monitoring, consistent with 40 CFR Part 258, as part of a comprehensiveagreement between the County and NDEP that addresses all the issues associated with theSunrise Landfill.

Please inform us as soon as possible if there is disagreement with the attached technical issue.Otherwise, please indicate the drilling and logging technique which will address the technicalissue and provide us with sufficient notice prior to commencing drilling so that we can havestaff on-site to observe. If there are questions, please contact me at (775) 687-4670 ext. 3001.

Bureau of Waste ManagementDE:kpattachmentSee page 2 for cc list.

Richard Holmes, Assistant County ManagerOffice of the County ManagerMarch 11, 1999Page 2

cc: Allen Biaggi, NDEPJohn Schiegel, Clark County Comprehensive PlanningMarty Manning. Clark County Public WorksGregory Walch, Esq., James, Driggs, Wakh et.al.Stephen Kalish, RSSDBob Abby, State Director, BLMMike Dwyer, BLM, Las Vegas DistrictDr. Donald Kwalick, CCHDClare Schmutz, CCHDSusanna Trujillo, EPA Region IX

Technical comments on Sunrise Mountain Landfill Ground-Water Monitoring Plan, datedFebruary 10, 1999:

In our letter of January 28, 1999, NDEP concurred with BLM's concern that a method oflithologic logging in the vicinity of the targeted screened interval was needed to supplementlogging of air rotary drill cuttings. Continuous coring was suggested in our letter. Accordingto CH2M Hill staff, drilling mud would be needed for this type of lithologic samplingtherefore the plan was submitted with the explanation that continuous coring would not bedone since use of drilling mud was undesirable. NDEP has discussed this matter further will1.staff hydrogeologists and we believe that coring can be accomplished without the use ofdrilling mud and that other methods of reliable lithologic logging are also available.

Recent drilling associated with the perchlorate problem south of Las Vegas wash provides anexample of an appropriate drilling and sampling technique. In this case, continuous 2 footcore samples were collected, with periodic advancement of surface casing and use of wire linetechniques. This drilling technique enabled well construction at a similar depth as thatanticipated at the Sunrise Landfill and was successful in detecting discrete zones of perchloratecontamination in the saturated zone. Brenda Pohlmann or Todd Croft of the NDEP Las Vegasoffice can provide more details regarding this drilling technique.

Another drilling technique which would provide good lithologic information is dual tubereverse rotary drilling. This method of drilling avoids contact of drill cuttings with theborehole providing more representative lithologic samples. I understand that a disadvantage ofthis technique is that it yields a fairly small diameter hole. A third alternative to providingacceptable lithologic information is to run geophysical logs of the boreholes to supplementlogging of air rotary drill cuttings. BLM staff suggest using caliper, neutron and gamma logsto detect changes in lithology, identify saturated zones and distinguish log responses due tobole diameter from lithologic change.

An acceptable method of obtaining reliable lithologic information is necessary for the proposedbaseline monitoring plan to be deemed acceptable by NDEP.

JAMES. DRIGGS, WALCH, SANTORO.: ••• n „„ KEARNEY, JOHNSON & THOMPSON- » . , o ; G r ATTORNEYS

3773 HOWARD HUGHES PARKWAY. SUITE 29ON

C. L*S VEOAS- NEVADA 89 I O9 JOHN E

GUCOOUT j WALCH "TO- <7Oa> 79 I -O3O8 J"4" E WNITWI..E. MIN.CHOCA* J. SAWTCWO PAX (7O3> 79 I • I 9 I 2 AV,V. Y GORDON

/-\ L- K"" W"JJ*M»EMAIL [email protected] TUIA.™ r W»CH»HANLUZABCTH t. WACHSMANJ OOUOLAS OftKMS. J*

OtAN 5

KIH«T c.JCNNiren J.RONALD J. THOMPSON ot"

February 19. 1999

OVERNIGHT DELIVERY

David EmmeChief. Bureau of Waste ManagementDepartment of Conservation and Natural ResourcesDivision of Environmental Protection333 West Nye Lane, Room 138Carson City, NV 89706-0851

Re: Surface Water Management Plan at the Closed Sunrise Mountain Landfill

Dear David:

Pursuant to Alan Caddy's discussions with Allen Biaggi, and pursuant to your letter ofJanuary 28, 1999, enclosed is Republic-Silver State Disposal's ("Republic's") Revised SurfaceWater Management Plan ("Plan") for the above-referenced landfill. The enclosed Plan includesmodifications to the eastern drainage channel in order to improve that structure as well asimprovements to the many other drainage berms and channels at the site.

The modifications planned for the site were based upon evaluation of the drainage structures'performance after the September 11, 1998. storm event. That event was determined to be greaterthan a 100-year storm event. The Plan continues to be based around the original design by HardingLawson Associates approved by Clark County Public Works, BLM, and the Clark County HealthDistrict. That design was based upon 25-year storm flow control (100-year storm control with"zero" freeboard) as required by applicable solid waste regulations. Calculations for new structuresare included with the drawings. Original design drawings should be referenced for those structuresthat will not be modified. Below is a brief description of the modifications proposed for the site.

The Eastern Drainage Channel will remain basically the same with the addition of bermedsides to protect a tuck trench for the liner. The liner will be welded together and the northern mouihof the channel will be widened to allow water to flow into the channel. The southern portion of thechannel will be improved by using an air track to improve flow through the bedrock area or flow willbe improved by removal of portions of waste cells so that flow of storm water will not impact theclosed waste cells adjacent to the channel.

David EmmeFebruary 19. 1999Page 2

Drainage Ditch # 1 is a new addition. Its design is similar to the changes planned for the otherdrainage ditches in that it will be a steel culvert under-lined with a plastic liner to minimizecorrosion. This ditch will include a new directional berm for flow control. Ditch #3.4,7,9,12, and14 will be reinstalled with a plastic liner under the structure and directional berms will be added forflow control.

Drainage Ditch $1 and 11, Channel #1,2, and 3. and Drainage Dike #1 and 2 will remainas originally designed. Directional berms will be heightened to improve performance.

Drainage Ditch # 5,6,8, and 10 will be moved away from on top of the waste onto the roadstructure so no liner will be necessary under the ditch. The mouth of Ditch 5 will be concrete linedand the Ditches will lead to new stilling basins at their base. A new stilling basin will also be addedfor collection of flows from Drainage Dikes #1 and 2.

As with Republic's February 11, 1999, Ground Water Monitoring Plan subminal. thescheduling and financing of the contemplated storm water control plan is predicated upon anagreement by the various stakeholders with respect to such matters. As described in my letter ofDecember 2, 1998, Republic's position at the closed Sunrise Mountain Landfill is that of amaintenance contractor. Nevertheless, Republic remains committed to working with your agency,as well as various departments within Clark County and BLM to insure proper storm watermanagement at the closed Sunrise Mountain Landfill.

Republic trusts the enclosed Surface Water Management Plan submitted herewithsatisfactorily addresses NDEP's comments. If you have any questions regarding the plan, please donot hesitate to me at any time.

Verv trulv vours.

Gregory J. Walch, Esq.

Enclosuresc: Allen Biaggi

John SchlegelMarty Manning (w/ enc.)Ed Wojcik. P.E. (w/ enc.)Stephen KalishRobert A. Groesbeck. Esq.Alan J. Caddy. M.S.Marie A. James. Esq.

7 wpo

United States Department of the Interior

BUREAU OF LAND MANAGEMENTLu Veju Field Office

*"?65 Ve»» DnvtIts Vej«j. Nevidi Ml OShttp://www.nv.blm.gov

la top* Refer To:

Nev-0462082912

(NV-053)C-I

MAR 041999

Mr. Dave EmmeBureau Chief, Bureau of Waste ManagementNevada Division of Environmental Protection333 W. Nye Lane Room 138Carson City, NV 89706-0851

Dear Mr. Emme:

The Bureau of Land Management (BLM) has reviewed the "Groundwater Monitoring PlanSunrise Mountain Landfill Clark County, Nevada" (the Plan) dated February 10, 1999. Thisdocument was submitted to the Nevada Division of Environmental Protection (NDEP) forapproval. BLM appreciates the opportunity to comment on the Plan. Our comments areenclosed.

BLM considers the Plan to be unacceptable. The Plan does not bring the landfill intocompliance with Nevada Administrative Code (NAC) Chapter 444, your October 16, 1998,Finding of Violation and Order, or Federal regulations (40 CFR 258). Though we havediscussed these issues with Clark County Public Works (CCPW) and Republic Silver StateDisposal Service (RSSDS) on numerous occasions, the Plan does not contain the technicalcomponents necessary to achieve compliance with the groundwater monitoring requirementsunder the regulations. BLM fully supports NDEP's efforts to ensure proper closure-and post-closure care practices required of CCPW and RSSDS.

If the Plan is meant to be a component of a more comprehensive groundwater monitoringplan that meets regulatory requirements, then this important consideration should be clearlystated in the Plan, as well as by NDEP. RSSDS and CCPW should understand that they areresponsible for implementation of a comprehensive plan, and that this Plan is not thecomplete groundwater monitoring plan which will be implemented at the Landfill.

We suggest the Plan be submitted through and/or concurred in by Clark County as well asconcurred in by NDEP's legal counsel.

Thank you for the opportunity to review and comment on the Plan.

ichael F. Dwy< rField Manager

Enclosure: Comments

cc (w/ enclosure): Rick Holmes, Clark CountyJohn Schlegel, Clark CountyMarty Manning, Clark CountySusanna Trujillo, EPA Region DC

Bureau of Land Management Commentson the February 10,1999

'Groundwater Monitoring Plan Sunrise Mountain Landfill Clark County, Nevada'1

Summary CommentstThe Bureau of Land Management (BLM) will only support a groundwater monitoring planthat, at a minimum, addresses or acknowledges the technical elements of the Code of FederalRegulations (CFR), specifically 40 CFR 258. These technical elements are absent from theFebruary 10th, 1999, Groundwater Monitoring Plan Sunrise Mountain Landfill Clark County,Nevada" (the Plan). Though this plan may be operating under a "cooperative agreement", itis ELM'S understanding that this agreement has not waived applicable laws. Environmentalmonitoring programs identify applicable laws which in turn dictate the technical objectivesand procedures of the entire program. Without technical elements founded in applicable lawsand guidance the monitoring program will not be protective of human health and theenvironment.

The BLM disagrees with the majority of technical principals presented in this Plan becausethey do not demonstrate an understanding of the technical issues presented by the SunriseMountain Landfill site conditions or the fundamentals of designing a groundwater monitoringprogram. To understand information being obtained from a groundwater monitoring program,the owner/operator must understand the hydrogeologic setting. This is the underlying principalof 40 CFR 258. In summary, this Plan's over-generalization of information results in a planthat is not defensible and does not provide an early detection of a release to groundwater.

The BLM views the development of a groundwater monitoring program as an iterativeprocess, requiring the assessment of data against program objectives and the identification ofadditional data gaps. This process is presented in various guidance documents provided bythe United States Environmental Protection Agency (EPA) and is absent from this Plan.Moreover, for all field work involving regulatory compliance, the BLM requests a formalapproval process, prior notification of field work and the development of reports that presentthe results and interpretations of the information obtained. These results must be compared toprogram objectives, both for regulatory compliance and technical elements, and the adequacyof the design assessed. This Plan does not propose the development of any report orassessment of the groundwater monitoring program consistent with a phased assessment.

This groundwater monitoring program should not proceed until a plan that ensuresconformance with applicable regulations and presents an understanding of the site-specificconditions of the Sunrise Mountain Landfill is developed.

Specific Comments:The following comments provide additional detail of ELM'S concerns regarding this Plan

Page 1-1. Thi^d |jne of the introduction paragraph."The Sunrise Mountain Landfill was closed in accordance with the Closure Plan dated April14, 1994."As previously noted, the BLM takes exception to this statement. The November 13th, 1997report prepared for BLM by Dynamac indicates otherwise.

Page 1-1. Subsection 1.1 Objectives of the Subsurface Investigation.As compared to the November 24, 1998 draft Plan, the objectives outlined on this pageremain basically the same and therefore many of the previous BLM comments remainapplicable. Simply put, without addressing the requirements for 40 CFR 258 groundwatermonitoring, the BLM will not support this Plan.

A proper monitoring plan must clearly discuss its goals and objectives before the technicalelements of the program can be developed. This requires a plan to recognized the governinglaws from which it operates. BLM believes 40 CFR 258 applies, specifically 40 CFR258.5Ic2 through 258.5 Idii. These regulations state:

40 CFR 258.5Ic2 The monitoring wells, piezometer, and analytical devices must beoperated and maintained so that they perform to the design specifications throughout

the life of the monitoring program.

40 CFR 258.5Id The number, spacing, and depths of the monitoring system shallbe:

(1) Determined based upon site-specific technical information that must includea thorough characterization of:

(I) Aquifer thickness, ground-water flow rate, ground-water flow directionincluding seasonal and temporal fluctuations in ground-water flow; and(ii) Saturated and unsaturated geologic units and fill material overlying theuppermost aquifer, and materials comprising the uppermost aquifer, andmaterials comprising the confining unit defining the lower boundary of theuppermost aquifer, including, but not limited to: Thickness, stratigraphy,lithology, hydraulic conductivities, porosities, and effective porosities?

Though some people may argue the implications presented by a few of these technicalelements, the operative phrase found in 40 258.5ld(l) cannot be ignored. Here theregulations specify the design of the monitoring system is to be; " ... based upon site-specifictechnical information that must include a thorough characterization". BLM is willing to makeavailable the United States Environmental Protection Agency's (EPA's) guidance documents"Solid Waste Disposal Facility Criteria", USEPA 530-R-93-017 and the EPA's "RCRAGround-Water Monitoring: Draft Technical Guidance" USEPA/530-R-93-001. These

documents provides discussions of the 258 regulations and their intentions. The rationale ofthe 258 technical elements is rudimentary, to instill upon the owner/operator that in order tounderstand the information being obtained from the groundwater monitoring program, theoperator must understand the hydrogeologic setting. Otherwise, misuse or erroneousinterpretations of the information will occur and incorrect decisions will be made.

Based upon the 40 CFR 258 regulations and the referenced guidance documents, thefollowing technical objectives should be used for this program:1. The identification and characterization of the lateral and vertical extent of the uppermostaquifer. The uppermost aquifer is defined as the uppermost hydrostratigraphic horizon which,when monitored, will provide early detection of a groundwater release. In addition, estimatesof the aquifer's hydraulic interconnectivness with the underlying and overlying lilhologies areto be assessed.2. The characterization of the lateral and vertical extent of the upper and lower confininglayers.This requires the ability to map the three dimensional extent of subsurface lithologies,stratigraphy, sedimentary facies, and geologic structure of the geologic material overlying andunderlying the uppermost aquifer.3. The identification and the ability to map the three dimensional extent of the lithologies ofgreater hydraulic permeability, and conversely those which may act as vertical or horizontalhydraulic boundaries, e.g., lower permeability. This objective is specific to the faulting.4. The program must be capable of detecting a statistical increase over site backgroundconditions for each of the analytes of the approved parameter list. Not only does this requirecharacterization of the background conditions, but also the development of a statisticalprocedure for making statistical comparisons (40 CFR 258.53(g)). This procedure is requiredto be presented within this Plan.5. On-going monitoring of groundwater quality is to be performed with consistent samplingand analytical procedures that are designed to ensure results are representative of thegroundwater quality.

A serious problem with this Plan's technical elements is its over-simplification of information.One example is the Plan's acknowledgment of the major geologic fault that crosses the mid-section of the landfill and how it [the fault] may act as a groundwater barrier (page 2-3, thirdparagraph). This conclusion is based upon mere speculation because the fault has not beencharacterized. Moreover, this Plan openly understands the possible interaction of the faultand groundwater movement by its attempt to dismiss a release to a distant surface waterspring (page 1-2, last paragraph). BLM is concerned that the Plan does not propose todetermine the affects of the fault on the groundwater regime even after it acknowledges itspresence and its ability to alter groundwater flow. The BLM requests the fault's role in thehydrogeologic setting be determined by installing at least two groundwater monitoring wellsin the fault zone.

A proper environmental plan/program compares monitoring results against workplanobjectives and makes a determination whether or not objectives are satisfied and, if not

satisfied, what actions are needed to resolve these issues. This iterative process provides astructure and a sense of direction of an on-going monitoring program rather than a short-termproject. Because BLM views this plan as a first step in the development of a groundwatermonitoring program, discussions regarding each objective and possible actions needed ifobjectives are not met must be presented. For example, if the groundwater flow directiondeveloped by the new wells is perplexing, then the hydrogeologic system is not understoodenough for the well network to be protective of human health and the environment. A secondsimple example, if the stratigraphic information obtained from the well-logs indicatessignificant lithologic variability, then additional information may be needed to fullyunderstand the cause of the variability, i.e. faulting or depositional. Geologic attributescontrol groundwater quality, flow direction and rate of flow and therefore the user mustunderstand the geologic and hydrogeologic setting before an understanding of the monitoringresults can be achieved

Pace 1-1. First Bullet. "Collect subsurface information to identify lithology. in the vicinityof the Landfill".It is very important to understand that simple identification of lithology does not present anunderstanding of either the geologic or hydrogeologic setting. The Plan must consider whataspects of the lithology are important in order to obtain an acceptable understanding basedupon objectives and regulations. Regarding lithology, the regulations require a thoroughcharacterization of lithologic thicknesses, stratigraphy (the spatial relationships betw?«n thevarious types of lithology), hydraulic conductivities, porosity and effective porosity (see 40CFR 258.5 Ic2 through 258.51dii). Current knowledge of the geologic setting at the SunriseLandfill indicates that a high degree of fracturing of the bedrock units exists. This secondaryporosity may have significant implications on the hydrogeologic setting of this site.Therefore, the degree of fracturing should be sought and documented on the drilling logs.Unfortunately, many lithologic attributes are not acquired by logging drill cuttings which isthe proposed method of this plan. Drill cuttings are the ground-up pieces of the lithologiesthat are returned to the ground surface by the drilling operation. Ground-up pieces of rock donot entirely resemble in-situ characteristics or the exact depths from which they occurred. Inaddition, thin saturated horizons or horizons of low water production go undetected.Additional comments regarding the logging technique follow (see comments for subsection3.1).

Logging drill cuttings does not provide detailed information. Without sufficient subsurfaceinformation the accuracy of well construction is compromised, stratigraphic correlations areover-generalized and often erroneous, and small scale sedimentary features, e.g. channeldeposits are never obtained. To assist in obtaining detailed descriptions of the lithology, itsthicknesses and depths, BLM strongly urges the use of borehole geophysics and/or continuouscore. These proven practices provide the necessary information to thoroughly characterize thegeologic environment. In audition, they provide valuable information that enables the accuratedesign and construction of a groundwater monitoring well. The additional costs of utilizingborehole geophysics is minimal as compared to the long-term implications of this program.

This Plan refutes ELM'S previous requests to core through the anticipated water zone bysuggesting muds are necessary to obtain core. The BLM disagrees with the need for muds inobtaining drilling core because air rotary methods are conducive to obtaining core from theindurated bedrock that is exposed at the Sunrise Landfill. Comments addressing subsection3.1 provide additional discussions regarding this issue.

Additional lithologic attributes not specifically addressed in the regulations, but also impartingcontrols on the rate and direction of ground water flow exist and should be considered. Theseincluded the lithologic strike and dip, sedimentary facies, and degree of weathering. All ofthese, including the degree of fracturing, are easily obtained if proper drilling techniques areused.

Page 1-1. Second Bullet "Install a sufficient number of groundwater monitoring wells "The criteria to make the determination that a "sufficient number of wells have been installed"are never mentioned in this Flan. The full scope of work for a groundwater monitoringprogram plan should be provided in this initial planning document. If uncertainties exist, adecision making process should be identified, along with possible alternatives that willprovide the program a sense of direction. The BLM suggests the Plan fully identify anddiscuss the information necessary for the proper implementation and use of a groundwaterprogram.

While the BLM did not receive a map showing the well locations, we believe a well shouldbe placed downgradient of the Northwest lagoon area. The well should be placed close to thewaste material and not at the property boundary. Groundwater monitoring wells should alsobe placed downgradient of the landfill and as close to the municipal waste cells as possible.In addition, wells should be installed side-gradient and in the same bedrock formations as thedowngradient wells. Wells should also be installed to determine the affects the fault mayhave on groundwater flow. The BLM believes the design of all groundwater monitoringsystems should be based upon an iterative approach. This allows for the refinement of datagaps and ultimately a system design that is protective of human health and the environment.Given the size and complexity of the Sunrise Landfill, the BLM assumes the final monitoringnetwork may consist of ten to fifteen wells.

Page 1-1. third bullet. " A brief 4-hour aquifer test.... to estimate hydraulic conductivitiesof the in-situ formation....."This statement eludes to an assumption that one homogeneous formation exists beneath thelandfill and that two aquifer tests will provided the range of possible hydraulic conductivitiesof underlying formation, however, the Plan also discusses the high degree of lateral variabilityin lithology (page 2-3, second paragraph). BLM asserts the variability is high and the intentof the aquifer tests should be specific towards testing the various lithologies found after thewells are installed. This may be the intent of this Plan, but without presenting clearobjectives it is an assumption a reader must make. The total number of aquifer tssts shouldbe flexible, to ensure all lithologic types are tested.

Valid aquifer testing typically requires testing durations greater than the 4-hours presented inthe Plan, otherwise assumptions are violated and results may be erroneous. Further, withoutpresenting testing procedures in this Plan, BLM can not assess the applicability of the Plan'saquifer testing method. This information needs to be presented in the final plan. BLMrecognizes the potential problems given the anticipated slow recharge, and suggests carefulconsideration of the testing procedure occur prior to its implementation. Cross plots derivedfrom borehole geophysical logs, can assist in this design by providing in-situ porosityestimates, detailed profiles of various iithologic attributes, thicknesses and saturation. BLMrequests this Plan consider the use of borehole geophysical logging and/or continuous core toassist in this issue as well as other issues.

Page 1-1. Fourth Bullet. ** Collect a sample .... quarterly for one year ... and analyze forAppendix I constituents...."BLM recognizes the list has changed to reflect previous comments, but for consistency thisbullet-item should add the parameters of chloride, nitrate and total dissolved solids (TDS).These parameters are presented on page 4-1, subsection 4.2, of this Plan. In addition, sulfateshould be added, as previously requested by BLM. This is a reactive product which isrequired by 258 regulation. Moreover, because they are very mobile, these additionalparameters can provide early detection of a groundwater release and reduce the cost ofpotential remedial actions. The additional costs imposed by these parameters is minimal.The BLM is pleased to see the proposed alternative list of analytical parameters. Per 258regulation, this list should be based upon the types, quantities, concentrations, mobility,stability, and persistence of waste types or by their reaction products (40 CFR 258.54a2i andii).

Page 1-2. Subsection 1.2.1 GeologyThough the general geologic information presented by this Plan is accurate, additionalinformation more pertinent to the groundwater objectives exist and can be easily obtained.This information consists of the surrounding geologic structure, i.e., strike and dip, localsedimentary facies and the degree of fracturing. The September! 1th, 1998 storm eventscoured away surficial sediments exposing the underlying bedrock from which this usefulinformation can be easily obtained. Field observations of these new geologic outcrops revealthe thickness of the background alluvium and the lack of shallow groundwater. The Planproposes to install background wells in this unsaturated alluvium, i.e., gravel. For manyreasons this Plan fails to properly design a program that is capable of defining a release. Asspecified in the regulations, a release is defined as a statistical difference, as compared tobackground. Background conditions must, therefore, be installed in similar Iithologic materialin order to be representative of the downgradient wells. Based upon this Plan, this is notpossible because all of the down gradient wells will be completed in bedrock. By ignoringthr use of background, the assessment of a potential groundwater release is unlikely.Additional comments are provided regarding this issue (see comments addressing the secondbullet on page 2-1,). The BLM requests the Plan be revised to properly follow theregulations.

2. Subsection 1.2.2 Groundwater Conditions"Ground-water is present at an estimated depth of approximately 160 to 230ft bgs....."This depth estimation is inconsistent with other sections of this Plan, specifically page 2-1(well depths of 180 to 280-ft) and page 3-1 (water depths of 140 to 190-ft.). The rationalefor these various depth estimates is not supported by previous documentation presented byRSSD. The BLM requests clarifications be made in the next groundwater monitoring plan.

This section of the Plan mistakenly assumes all of lithology beneath the landfill is going tohave similar characteristics as that found in the abandoned Well-B. Furthermore, this overgeneralization is inconsistent with other discussions found, where the geology beneath the siteis considered to possess a high degree of lithologic variability (see page 2-3, secondparagraph, of this Plan). Due to the poor historical documentation of Well-B, sample resultsetc., the BLM does not place much value on this comparison. Moreover, the hydraulicproperties of a fault zone versus those of undisturbed rock can be significantly different. Thedegree of fracturing found within Well-B is unknown because only cuttings were logged.BLM has provided numerous comments regarding the use of borehole geophysics andcontinuous core and the need to thoroughly characterize the geologic setting. Furthermore,the nearby water production well operated by Nevada Ready Mix supports the fact thatlithologic variability exists. The broad, generalizing assumptions made by this Plan should beavoided until acceptable data have been acquired.

Page 1-2. Subsection 1.2.3. Third paragraph. " A water sample was collected.... from a watertank ".The procedures for the collection of this sample were never provided to the BLM and a grabsample from this open water tank violates many sampling procedures and therefore severelylimits the use of the result. A sample should be collected directly from the well head after ithas been purged so it is representative of the groundwater conditions and not that of theholding tank.

Page 1-2. Subsection 1.2.3. Fourth paragraph, last paragraph. "Because no VOCs weredetected there is no evidence that a release has migrated to the spring."BLM comments on the November 24, 1998, draft discuss the inaccuracies of this statement.To summarize, the presence or absence of Volatile Organic Compounds (VOCs) at the springcan not be used to make this conclusion. It is a well known fact that various retardationfactors slow the rate of migration of VOCs. More importantly there is a serious lack ofevidence to suggest this spring, located several miles away, is hydraulicaily connected to thelandfill. Nonetheless, other water quality parameters, not as affected by retardation, can beused as good indicators of a more serious release. Unfortunately, these parameters were notused in this assessment. For landfills, these parameters include nitrate, chloride, sulfate andTDS.

Page 1-3. First sentence. "A leachate sample was collected from the landfill. This watersample represents surface water.... *.The conclusion made, that this is surface water flowing back to the channel, is unfounded.

Additional characterization is need to support this conclusion. Leachate production wasprobably occurring before the storm event and the storm's subsequent erosion of thenir.ply provided an exposure of the "seep line" along the top of bedrock. The presence ofthis leachate seep has significant implications and irrefutably presents evidence ofgroundwater vulnerability at this site. In addition, if shallow zones of saturation exist, theyshould be monitored along with the deeper aquifer. The drilling techniques should bemodified to use borehole geophysical logging and/or continuous coring so the detection ofthese thin shallow zones is possible because the drilling and construction methods of thegroundwater monitoring well must be exact to prohibit the cross contamination of theseleachate zones to the deeper aquifer. BLM requests these procedures be added to the finalgroundwater monitoring plan.

Page 2-1. Scope of Field Investigation.As previously commented, the BLM suggests CCPW and RSSDS review the regulatoryrequirements and integrate the required objectives into this Plan. Currently, very few aspectsof the applicable regulations are being satisfied. The objectives and requirements of agroundwater monitoring program developed in accordance with 40 CFR 258 are clear andrequire information to be site-specific with well locations directed by the identification ofpotential pathways. These pathways are controlled by geologic structure, stratigraphy, andpast landfill practices. These pathways must be identified and monitored (40 CFR258.5l(b)(d)). Based upon these requireuents, the BLM urges CCPW and RSSDS to performa thorough hydrogeologic characterization prior to the installation of a final groundwatermonitoring well network.

Page 2-1. First Bullet. " Install six downgradient wells. as close TO the waste aspracticable".The regulations (40 CFR 258.40d) specify the maximum distance away from the wastematerial is 150 meters. The locations of the wells should, at a minimum, be assessed againstthis distance criteria, while keeping in mind the earlier a release is detected the less expensiveand more efficient additional characterization and remedial actions will become.

The BLM considers the efforts proposed by this Plan as the first phase in the design of agroundwater monitoring program for the Sunrise Landfill and additional wells may be needed.

Page 2-1. Second Bullet. "Install one or two monitoring wells ... upgradient.... and drilled toihe depth of bedrock."As noted in previous BLM comments, the proposed background locations and completiondepths of the proposed monitoring wells present significant problems to the implementation ofthis groundwater monitoring program. First, the Plan proposes to complete background wellsin alluvium north of the landfill while all of the downgradient wells are proposed to becompleted in bedrock of the Muddy Creek Formation. The differences in lithology alone willcause dramatic differences in the water quality between the two aquifers which may falselyindicate a groundwater release. Secondly, the September storm event produced local scouringof the alluvium, to the depths of bedrock. Based upon these scoured locations, the thickness

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of the alluvium, in outcrop, is less than ten feet and unsaturated. The exposed bedrock,however, is highly fractured, steeply dipping sandstone that strikes in the direction ofFrenchman Canyon. At some unknown depth beneath this canyon, groundwater would befound, but it is highly unlikely the Muddy Creek Formation will be found at this location.The background monitoring wells must be completed in the same geologic formations as thedowngradient monitoring wells so as to provide representative results. The BLM stronglyurges CCPW and RSSDS to reconsider their proposed background locations and assess theuse of side-gradient wells that are located in the same formation as their downgradient wells,the Muddy Creek Formation. In the fault zone, formations other than the Muddy CreekFormation may be found, this will add a complexity not yet discussed.

The Plan fails to present the proposed methodology for comparing the downgradient waterquality to background conditions. This is required by 40 CFR 258.53(g). The BLM requeststhis Plan be revised to reflect the technical requirements of the regulations.

Both BLM and NDEP should be notified two weeks prior to the sampling in order to allowregulatory oversight and to opportunity to collect split samples. All of the wells should bemonitored quarterly for the first two years to establish seasonal effect, i.e., baseline. Afterthis initial period and if no detections are discovered, semiannual monitoring should occur.The 258 regulations specify no less than semi-annual monitoring.

Page 2-L thjrd bullet. " Complete an aquifer test.... at two of the wells ..."The potential problems with this statement are discussed earlier in this set of comments (seecomments for page 1-1, third bullet).

fage 2-1. Fourth Bullet. "Complete a full round of water level measurements from all newwells quarterly for one year."The collection of static water level measurements must coincide with each sampling event.As previously commented, samples should be collected quarterly for the first year and no lessthan semi-annually thereafter.

Page 2-1. Fifth Bullet. "Collect quarterly groundwater samples ... for ...Appendix I andChloride ...."This statement should be consistent with Subsection 1.1 (last bullet). As previously noted, inthese comments, sulfate should be added.

Page 2-1. Section 2.1. Well Locations and DepthsEven in a simple geologic setting, six downgradient monitoring wells should not beconsidered sufficient for a landfill the size or as complex as the Sunrise Mountain Landfill.Distances of one-half mile separate the proposed wells. This does not provide the spatialcoverage necessary to identify all potential groundwater pathways at this site or allow for theearly detection of a groundwater release. This initial phase should attempt to assess theknown data gaps and later refine site knowledge enough to install a regulatory-based wellnetwork that is protective of human health and the environment

Subsection %.l. Item #1.The assumed flow direction, based upon data from Emcon and Southern Nevada WaterAuthority (SNWA), can not be supported because site specific data has never been obtainedfrom the site. If the flow direction is indeed to the west or southwest, wells placed on theeast side may suffice as background wells for the Muddy Creek Formation, i.e., side-gradient.In addition, a solid waste cell and liquids dump are located in the northwest area and needs tobe monitored by the installation of a monitoring well. The sampling and analysis of a springlocated to the east, opposite the flow directions indicated by EMCON and SNWA, of thelandfill indicates the uncertain about the hydrogeologic setting of this site.

Subsection 2.1. Item #2The separation of one-half mile between wells is not acceptable when the currentunderstanding of site conditions is severely limited. This does not allow for the earlydetection of a groundwater release. A release could easily migrate between wells.

Subsection 2.1. Item #3.In the end, the location(s) for background groundwater monitoring well(s) may need to be offthe current landfill lease. The majority of land surrounding the landfill is public landadministered by the BLM. With the exception of the ISA area, authorization for installationof a groundwater monitoring well(s) will require minimal administrative effort.

Subsection 2.1. Item #4.The potential for the various Quaternary channels to behave as preferential pathways forleachate is correct, however, the targeted depths of the wells are much greater, therebymaking their proximity to the channels irrelevant. If the Plan's intentions are to monitorlocations near permeable pathways then more attention should be given to monitoring thevadose zone and characterization of the fault traces.

This paragraph questions if leachate is being generated, yet the Plan terms a previous sampleas "a leachate sample". Nonetheless, the analytical results support the fact that leachateproduction is occurring in this landfill.

Subsection 2.1. Item #5.As previously noted, proven technology exists which can greatly enhance the ability to detectwater bearing zones, e.g., continuous coring and borehole geophysics. These methodologiesshould be used for this program.

Page 2-2. Subsection 2.2 Use of BLM Data to Assist in Well Locations.We have provided numerous comments regarding this issue and have not changed ouropinion. The information provided in BLM's geophysical report was not utilized in thedesign of this initial groundwater monitoring network. BLM does not object to this oversightbecause any geophysical result should be considered preliminary until confirmed by drilling,however, this Plan makes no attempt to confirm similar findings made by other geologicprofessionals, e.g., the fault.

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Several inconsistencies are produced by the Plan's attempt to invalidate the geophysics. First,the Plan states "that no permeable zone was determined by the geophysics and therefore itwas not used to locate wells'. This statement is incorrect, but more importantly, this Planfails to identify permeable zones as an objective for well completion. For example, the Planfails to characterize the effects of the fault, e.g., determine if the fault is more or lesspermeable than the surrounding lithology. The geophysical report does present potentialpermeable pathways through the identification of the primary fault, two additional fault tracesand one potentially coarse marker layer. The orientation of these faults is consistent withothers in the area and should be investigated as part of this program.

This Plan errors in its conclusion regarding the lateral extent of the geophysical marker layer.The Plan states the driller's log of well-B consists of clay and gravel and doesn't match theresistivity values of the marker layer. The BLM suggests reassessment of the geophysicalreport because the geophysics does indeed support the driller's log (see cross section A-l andA-2). The electrical sounding nearest to the location of Well-B is VES-3 and data from thissounding does not indicate the presence of the highly resistive marker layer. Therefore, thegeophysics does correlate with Well-B. The reason for the marker layer's absence is spatialvariability, e.g., lithologic heterogeneity. The cause of this heterogeneity is, however,unknown but could be caused by faulting or sedimentary facies. This Plan acknowledges theexistence of lithologic variability, but does not appear to be concerned with its affects on thedesign of this monitoring network. This produces significant inconsistencies within the Plan.The BLM suggests this Plan remove these inconsistencies by following good scientificpractices and the 40 CFR 258 regulations.

Page 2-3. Second Paragraph. "This complex geologic setting is conducive to a high degree oflateral variability in lithology."BLM agrees with this statement and suggests this Plan modify the technical objectives toaddress this "complexity" by thoroughly characterizing the geologic setting. This must beaccomplished before a groundwater monitoring program can be developed. Furthermore, it isrequired before the landfill can be properly closed. The BLM requests 40 CFR 258regulations are used in the design and implementation of this groundwater monitoringprogram.

Electrical resistivity is commonly used to detect lateral geologic variation, knowing this doesbreak assumptions. Nonetheless, when the objective of the survey was to assess the overallgeologic complexity, by looking for sudden electrical changes, this assumption is notweighted heavily. Once detailed drilling logs are obtained, BLM plans to refine theirgeophysical interpretations, however, the overall result of being a complex geologic settingwill not likely change.

Page 2-3. Paragraph 3. fifth line. "If faulting is present the fault-gouge may act as abarrier to groundwater flow."The BLM is very concerned that this Plan can acknowledge the potential affects of this fault,but not investigate it. Conclusions regarding the affects of this fault can not be drawn until it

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is characterized. The BLM requests the groundwater-fault interaction be characterized as panof this program.

Page 2-3. Paragraph 4As discussed earlier, the geophysical marker laver is not found in Well-B or the nearestgeophysical sounding location (VES-3). The BLM directs readers to cross sections A-l andA-2 of the geophysical report and the raw data of VES-3. Therefore, the correct conclusionis drawn in the geophysical report; that the geophysics agrees with the Well-B. However, asmost ail geologic professionals will agree, lithologic detail from a drillers log is nearly alwayslacking in quality. In short, the geophysical survey indicates lateral variability of the markerlayer. This fits the interpretation made by this Plan (see paragraph 2 of this page), but thecause of this variability must be determined. The BLM performed this geophysical survey toassess the overall complexity of the site in order to assist in the design of the groundwatermonitoring program. The BLM again requests a thorough characterization of the geologicand hydrogeologic settings be performed prior to the finalization of the groundwatermonitoring program.

Page 3-1. Section 3. Monitoring Well InstallationsAll of the technical objectives presented in this brief paragraph are needed, however, CCPWand RSSDS must realize their main objective is regulatory compliance. Because this Plandoes not meet the regulatory requirements, groundwater monitoring efforts should not proceeduntil this Plan has been revised. The revised Plan, as with all future planning documents,should be reviewed by BLM and Clark County and reviewed and approved by NDEP priorto implementation.

The first sentence of this section; "The purpose of installing groundwater monitoring wells isto characterize...."This objective is not presented in the discussion of the Plan's objectives (subsection 1.1, page1-1). As previously discussed, the objectives of this Plan must be detailed and conform withthe requirements of 40 CFR 258. The BLM requests this Plan be revised to reflect theserequirements.

Page 3-1. subsection 3.1. Drilling and Soil LoggingBLM has provided previous comments discussing the problems that arise from loggingcuttings. While the only advantage of logging cuttings is the reduced cost, the quality ofinformation obtained from this practice is substandard. Moreover, the management decisionsthat are based upon this information also suffer, e.g., well construction. The most commonproblems that arise from logging cuttings are: inaccurate drill logs because the crushed piecesof rock do not resemble their natural conditions and determining the exact depth to alithologic contact. In addition, thin saturated horizons or horizons that slowly produce waterare very difficult to detect and many of these produce enough water to be monitored.Moreover, these perched zones can provide early detection of a release.

Given the need for long-term monitoring it is in the best interest of the public that protection

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of human health and the environment is based upon a thorough characterization, i.e., athorough understanding of the site. Based upon this Plan, attainment of this understanding isnot possible. The BLM requests this Plan be changed to comply with the appropriateregulations.

The post-closure care period for a Municipal Solid Waste Landfill (MSWLF) is 30 years. Inaddition, the regulations state: "Once established at a MSWLF [the landfill] unit, groundwatermonitoring shall be conducted throughout the active life and post-closure care period of thatMSWLF9 (40 CFR 258.5 (f) and"77i« monitoring wells, piezometer, and other measurement,sampling, and analytical devices must be operated and maintained so that they perform to thedesign specifications throughout the life of the monitoring program." (40 CFR 258.5 l(c)(2).It is in the best interest of the public to have this program implemented correctly becausemust operate efficiently for a long time.

Page 3-1. subsection 3.1. third paragraph. " In order to core the bottom of the borehole, theuse of drilling mud would be needed." and " this is considered too risky."The BLM disagrees with this statement. Coring with air rotary is a common practice,especially through competent bedrock formations. Muds are typically used for boreholestability and better circulation of cuttings. Neither of these problems have been documentedin past drilling at the Sunrise Landfill. The BLM requests continuous coring and boreholegeophysical logging be performed on all drill locations at the Sunrise Landfill. This willassure all interested parties that accurate data and information are obtained and thegroundwater program is designed correctly.

Page 3-1. subsection ft,], thjrd paragraph. "Given the very slow recharge rate of the twopreviously existing groundwater wells....."The BLM has always understood the other well to be dry. In the context of this paragraph, itappears water was once detected in this well. The BLM requests confirmation of thisstatement.

Page 3-1. subsection 3.2. second sentence. "The depth to groundwater .... is estimated to beapproximately 140feet to 190feet."As previously discussed, this depth estimate is inconsistent with other depths estimatesprovided in this Plan. The BLM requests these inconsistencies be removed.

fage 3-1. fourth line. " the depth to groundwater may be difficult :o determine (luringdrilling, due to the slow rate at which the wells recharge."The BLM has provided numerous comments regarding the proposed logging procedures ofthis Plan. The problems identified by this Plan, e.g., the ability to detect first water andassessing small-scale geologic features can be easily overcome with the use of propertechniques. The correct techniques should use continuous core and/or borehole geophysics.To summarize, the logging of cuttings is simply an inexpensive manner of obtaining anovergeneralized description of the lithology. It does very little in achieving the groundwaterobjectives of 40 CFR 258. The BLM requests the appropriate techniques be used in the

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design of this groundwater monitoring program.

Page 3-1. subsection 3.2. ninth line. "Close examination of the core ..."Unless the proposed logging procedure has Changed, the term "core" is inappropriately usedin this sentence. This misuse occurs again in the last sentence of this paragraph.

Page 3-2. subsection 3.3. fifth line. "Based upon grain size distribution alternate wellscreen slot size and filter pack gradations for the remaining wells."This Plan again assumes all the lithologies will be the same, yet in other discussions itacknowledges a high degree of lithologic variability. These inconsistencies should beremoved from the Plan or discussed in more detail.

Subsection 3.3 Well Construction and CompletionThe procedure for selecting filter pack material as well as the overall well construction shouldfollow EPA procedures. These references should be presented in this Plan. For example, the2-ft of bentonite seal needs to be hydrated before the remainder of the annulus is pressuregrouted.

Page 3-2. Subsection 3.4 Well DevelopmentFirst bullet; "Initial development using a surge block, and bailer as necessary."It is unclear what "as necessary" truly means. Because referenced procedures are notprovided in this Plan, field personnel are left to their own judgement which may differ formothers involved in this program. Therefore, EPA procedures should be referenced in thissubsection.

Subsection 3.5 Decontamination ProceduresThough the Plan discusses the need to use decontaminated drilling and sampling equipment, itallows for the possibility of drilling equipment of becoming contaminated while beingtransported to the site and then being used on-site for the first well.. The Plan should preventthis from happening by requiring the equipment to be decontaminated prior to mobilizationand on-site again, prior to use.

Page 4-1. Section 4. Groundwater Sampling ProceduresSubsection 4.1 Groundwater Sampling

Fourth bullet and Fifth bullets:EPA procedures should be referenced, particularly for the use of impeller pumps, such as theR«di-Flow 2, for the sampling of VOCs. The BLM prefers bailers or in-situ samplers for theVOC sampling because impeller pumps are known to cause off-gassing of VOCs even at adecreased pumping rate. This off-gassing leads to a decrease in sample concentration.

The Plan should also specify "stainless steel or teflon bailers" may be used for sampling notsimply "mild steel". Teflon and stainless steel are the components accepted in EPA protocol.

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Seventh bullgt:The recharge rates of each well should be recorded in the field log books. This will assist inthe logistics of future sampling efforts, particularly for slow recharging wells.

Subsection 4.2 Request for AnalysisAs previously suggested and justified, the following parameters should be consistent withother discussions of this Plan. In addition, sulfate should be added to the list. The analyticalcost for this parameter is minimal, but it may provide useful information.

Page 4-1. Subsection 4.3 Quality Assurance/Quality ControlThe Plan should acknowledge that split samples may be collected and analyzed by theregulatory authorities.

Page 4-2. first sentence. " .... will be taken during the sampling of all 5 or 6 wells,"This statement is inconsistent with other sections of this Plan where it states 6 downgradientwells and one or two upgradient wells will be installed.

Subsection 4.4 Sample Handling. Packagine. and ShippingThese procedures should reference the appropriate EPA documents as well as the all of thetechnical requirements and procedures.

Page 5-1. Section 5 Waste ManagementThe proposed method for handling drill cuttings is contingent upon the analytical results ofthe groundwater. The saturated zone of each well represents only a small portion of theentire depth of a well. The drill cuttings from the unsaturated portion of each well should befield screened for VOCs and if any detections are found, proper disposal practices should becarried out. Health and safety monitoring should include VOC screening and subsequentlythe instrumentation will be available at each drill site for the screening of drill cuttings. TheBLM suggests the addition of field screening for VOCs should be added to the Plan.

Water produced during the aquifer test (see Section 2, third bullet) should be collected andhandled in the same manner as development water. This should be addressed here in thePlan.

The handling of Personnel Protective Equipment (PPE) needs to be addressed in this section.

Page 6-1. Section 6 ReferencesBecause all of the objectives of this Plan must satisfy regulatory requirements, the regulatorystatutes and applicable guidance documents should be referenced in this section of the Plan.

15

STATE CF NEVADA••>ETER C MORROS Dirretoi BOB MILLER

A1J.C.N BIACCI. jUmatatntor Cortnar

^^^^7021 687-W70 Conrco«___ _„ ,„ - FacilitiesTOD 667.4678

Pollution conuw V x « X f c m r uiuiilv R»mingtl* 6*7-5*56 ^^gj^^ Fmcumii* 6S7-63W

RciVj:i:.i:r joi Rcljnu^ionrfr 6M-5259 DEPARTMENT OF CONSERVATION AND NATURAL RESOLRCLS

DIVISION OF ENVIRONMENTAL PROTECTION333 W. Nyc Lane. Room 1J8

Carton City. Nevada S970&-OS51

Jamiiiy 28, 1999Mr. Gregory J. Walcfa, Esq.James, Driggs, Walch, Santoro & Thompson3773 Howard Hughes Pkwy, Suite 290NLas Vegas, NV 89109

RE. Comments on the proposed Sunrise I^ndfil] Surface Water Management Plan and GroundWater Monitoring Plan.

Dear Mr. Walch:

This letter provides comments on documents that you have submitted to the Division on behalf ofRepublic Silver State Disposal (RSSD) relating to storm water management and ground watermonitoring at the Sunrise landfill.

Storm WfttCT M*n*ggmcnt:In response to a Finding of Violation and Order issued by the Division on October 5, 1998, yousubmitted a report on November 6, 1998, prepared by Harding Lawson Associates titled, "AnEvaluation of the Sunrise Mountain Landfill Surface Water Management Plan Following theSeptember 11, 1998 Storm. " In a letter dated November 23, 1998, the Division acknowledgedreceipt of the report but noted noncompliance with item 2 of the Order which requires submirtaJof complete plans, specifications and a schedule for implementation.

On January 4, 1999, you transmitted design and construction plans for the surface water drainagesystem which are described in your cover letter as "preliminary" and "exclusive of the easterndrainage channel." The sheet index for the engineering plans lists 13 sheets, yet only sheets 1 , 2and A were submitted. These plans were not certified by a Nevada Professional Engineer and donot include any calculations or other documentation which would support the proposed design ofthe drainage structures depicted in the plans.

In short, the plans are incomplete and provide no substance for technical review. We requirecomplete plans, specifications and a schedule for review. The plans should be transmitted throughand accepted by the Clark County Public Works Department. If access to or disturbance of BLMoff-lease areas is required, Clark County must make these needs known to BLM and inmateprocedures to gain access.

Mr Gregory J. Walch, L ,.James, Driggs, Walch, Santoro & ThompsonJanuary 28, 1999Page 2

Ground water monitoring:In response to a Finding of Violation and Order issued by the Division on October 16,1998, youfiled a request on October 29,1998, for an appeal hearing on behalf of RSSD. On December 2,1998, you submitted a plan prepared by CH2M Hill titled "Proposed Groundwater MonitoringPlan, Sunrise Mountain Landfill, Clark County Nevada." In your cover letter, you state thatRSSD is willing to implement the plan under three conditions:

1. NDEP rescind* ha October 16,1998 Finding of Violation and Order,2. Republic and Clark County enter an Agreement to provide for the additional work; and3. rTOEP and RepubHc enter an agreememfadkatingrroEPwffln^

grouadwater monitoring at the landfill provided the Monitoring Plan wells do not revealthe existence of landfill caused groundwater contamination.

The Division has two fundamental comments regarding this proposal. First, the monitoring planas presented is technically ITM^^TTP^ Secondly, the Division wfll not agree to condition number3. However, if a technically adequate plan is submitted that responds to the Division's commentsand RSSD and the County enter an agreement to provide for implementation of the plan, theDivision will agree to rescind its Finding of Violation and Order.

BLM has provided extensive comments on the monitoring plan. Their comments are attached foryour review and consideration. The Division's specific comments on the momtori&s pl*n &re «follows:

• While a site as large as the Sunrise Landfill could arguably warrant more detailedinvestigation, the Division would accept a mrnimum of six (6) monitoring wells along thedowngradient perimeter of the landfill. Adding two additional weHs to the proposed plan,located along the southeast and east side of the landfill, would provide wells spacedroughly a half mile apart-certainry not an excessive degree of investigation. We agreewith BLM th** after the local gradient is determined, samples from a lateral or side-gradient well could be used as an indicator of background water quality.

• To provide an ""fal indication of ground water quality and a baseline for any subsequentsampling, the workplan should propose collection and analysis of ground water samplesquarterly for at least one year. At the end of a year, the Division win determine the needfor additional sampling Samples should be analyzed for compounds listed in Appendix Iof 40 CFR Part 258 and chloride, nitrate, and total dissolved solids.

• The screened intervals of monitoring wells should be no more than 20 feet in length. Weagree with BLM's suggestion that continuous coring near the anticipated depth of thewater table would enable field personnel to determine proper screen placement.

Mr. Gregory J. Walch, Esq.James, Driggs, Walch, Santoro & ThompsonJanuary 28, 1999Page 3

• Finally, we agree with BLM's comment that a purging and sample collection techniqueshould be selected which, minimizes sample bias or off-gassing of VOCs. In addition, theplan should provide for notification of the Division at least two weeks prior to fieldactivities.

As discussed during our meeting on January 21,1999, we will expect complete plans for thestormwater drainage system and ground water monitoring system that are responsive to ourcomments within the next two weeks. If there are questions, please contact me at 775/687-4670x3001.

Sincerely,

David Emmc, ChiefBureau of Waste Management

Attachment

oc: AlkaBiaa^Adarimstralcr.NDEPBonne Rinaldi, Deputy County Manager, CUrk CountyRkk Hoboea« Gink County Comprehensive FlemingMartin Miming. Clark County Public WeeksRobert Groesbeck, Esq.., RSSDStephen Kiliih,RSSDDr. Dow Id Kwtbck, CCHDClare Scfamutz, CCHDEdWcjotCCHDMike Dwytr, BLM. Us Wps Diatric*Mike Mcrsa, BLM. Us Vegas DistrictSussma TrujiUo, EPA DC

369220? TXECUTIUE OFFICES 486 P01 r«Y 04 '«g 13:31

May 4, 1998

1-Via FtcsiinUe - 870-0811and Pint Clais Mall

R. Ian Ross, Legal CounselClark County Health District625 Shadow LaneLas Vegas. NV 89106

Re: Comment! to Proposed Agreement of April 14/Sunrise Landfill ("Sunrise")

Dear Mr. Ross:

As I indicated in cur telephone discussion last week, our company is in the process ofpreparing our response to the above-referenced Agreement Although we h&ve ft number ofrecommendations which we chink will assist in remedying the issues surrounding the closedSunrise Landfill, i; would be inappropriate to release these recommendations until we have firsthad an opportunity :o coordinate our response with Clark County, Public Works Department Werecently had occasion to meet with representatives of Public Works, and look forward toscheduling a follow-up meeting some time this week.

It remains our position that Sunrise was closed in a timely manner and in conformancewith all pertinent rules and regulations in effect at the time of closure. The independentengineering conducted by Vector Engineering and Harding Lawson Associates bear this out.

Our company remains committed to Marking toward a satisfactory resolution of thepertinent issues relating to Sunrise, namely, landfill gas emissions and groundwj'.er -nonitoriru.

We are hopeful that the BLM will recognize the importance of our participation in thesediscussions and will invite our representatives to future meetings. It remains our opinion thatthese matters can only be resolved If all panics are included In the process.

770 Easi Sahara Awu* • P.O. Boot 96503 • Us V*ga*. N«Kfe B9193-8508»Tiltptxm (702) 735-5151 • Fax (702) 735-1986

3692206 ""ECUTIUE OFFICES PS2 -96

R. Ian Ross, Legal CounselMay 4, 1998Page 2

1 will follow-up with additional comments after we have met with Public Works. Shouldyou have any questions in the interim, as always, please do not hesitate to contact me direcuyat 734-5427.

Sincerely,

RAG/kl

xc: Stephen Kalish, PresidentAlan Gaddy, Vice PresidentMarty Manning, Director of

Public Works, Clark County

m_A. uroesbeckGeneral

jted States Depanment o. .he Interior

3UREAU OF LAND MANAGEMENTLas Vegas Reid Offict

4765 Ve|as DriveLas Vepi. Nevada 89108

In Reply Refer To:Nev-046:08

2912(NV-053)

Mr. Ian Ross ^""""WH^ DlW^_ APR 3 01993Legal CounselClark County Health District625 Shadow LaneP. O. Box 3902Las Vegas. NV 89127

Dear Mr. Ross:

Enclosed are BLM's Concept Points for the Sunrise Mountain Landfill Agreement which willbe discussed at our meeting on May 5. 1998. In addition to the Agreement, we would likesigning of the landfill and gate access to be placed on the meeting agenda.

Sincerely,

Michael F DwyerDistrict Manager

Enclosure: Concept Points

• / I " iMt n < j

C6: £t £ CHIEF HEALTH OFFICER

'•' S-

CONCEPT POTNJC ynp ^T^JSE MC-CTTAIW LANDFILL

Recitals

1. This Agreement is between the Bureau of Land Management('BLM'), Clark County Department of Public Works. Clark CountyHealth District and the Nevada Division of Environmental ProtectionCNDEP').

2. The Sunrise Mountain Landfill ('Sunrise Landfill') is locatedon land owned by the United States and under the administrativejurisdiction of ELM.

3. While the United States owns the land underlying the SunriseLandfill, Clark County is the owner and operator of the landfill.

4. Clark County leased the 720-acre landfill site from the UnitedStates through two leases (collectively referred to as "NEV-046208*) authorized under the Recreation and Public Purposes Act,43 United States Code CU.S.C.'J section 869 et sec.

5. The first lease, covering a 320-acre section of the SunriseLandfill, was issued in 1962 for a term of 20 years. The lease wasrenewed in 1982 for an additional 20 year period. BLH considersthe lease to be in full force and effect since Clark County has notcomplied with the requirements for relinquishment of the lease.

6. The second lease, for the remaining 400-ecre area of theSunrise Landfill, was issued in 1985, and renewed through May 21,1994. In 199S, Clark County refused to renew the lease. BLMconsiders the lease to be in full force and effect since ClarkCounty has not complied with the requirements for relinquishment ofthe lease.

7. Sunrise Landfill operations were also conducted in an area offthe leased areas, identified more particularly in the CCJMReconnaissance Investigation, dated March 18, 1998, as the NorthOff Lease Area and the Northwest Off Lease Area. The December 1986EMCON report prepared for Disposal Urban Maintenance ProcessingCompany Inc. ("DUMPCo"), also documented the off lease areas aspart of the landfill. The off lease portion is a part of chelandfill and must be addressed in the closure and post-closurerequirements for the Sunrise Landfill.

8. On April 24, 1994, BLM, Clark County Public Works, ClarkCounty Health District and DUMPCo signed an 'Agreement of Parties'agreeing to close the Sunrise Landfill in accordance with 'theClosure Plan and with the construction drawings and specifications*incorporated into the Closure ?lan. As specified in the ClosurePlan, the landfill was to be closed in accordance with allapplicable local, state and federal laws.

9. On April 10, 1995, BLM, Clark County Public Works, Clark

County Health District and DUMFCo determined thac the SunriseLandfill had been closed in accordance with the Closure Plan. Inmaking this conclusion. ELM relied on the determination of ClarkCounty Health District.

10. BLM believes that the Sunrise Landfill was not closed inaccordance with the Closure Plan. BLM has documented that thelandfill closure as constructed deviates significantly from theClosure Plan. Deviations from the Closure Plan include theeffectiveness and integrity of the cap, run-on/run-off controls,inadequate groundwater and gas monitoring.

11. By letter dated March 11, 1996, the United StatesEnvironmental Protection Agency, Region XX ('EPA Region IX*), hasdetermined that the Sunrise Landfill must comply with therequirements of 40 Code of Federal Regulations CC.F.R. •) Part 258,since the landfill did not meet the October 9, 1994, deadline forfacility capping and closure.

12. The NDEP concurred in EPA, Region IX's determination regardingr.he applicability of the 40 C.F.R. Part 258 requirements at theSunrise Landfill by letter of March 6, 1998. In fact, NDEPspecifically cautioned Clark County Health District, by letter ofAugust 1, 1994, regarding the necessity of completing closure ofthe Sunrise Landfill prior to the October 9, 1994, deadline toavoid full applicability 40 C.F.R. Part 258.

13. Clark County Health District granted Clark County Public Worksan extension of time to comply with the closure requirements. EPARegion IX and NDEP dispute Clark County Health District's authorityto grant an extension of time to the federal landfill closurecompliance deadline. Clark County Health District maintains itsauthority to grant the extension of time and asserts that theSunrise Landfill has been closed in accordance with applicable law.

14. By letter of April 10, 1998, EPA Region IX, has determinedthat the BLM Reconnaissance Investigation Report referenced inparagraph 7 is technically sound, that additional investigation iswarranted to determine the nature and extent of contamination atthe site, that additional investigation of the off lease lagoonareas is necessary and that desert tortoise .\ssues are to beaddressed pursuant to requirements of the Endangered Species Actand the National Environmental Policy Act. BLM concurs,with theserequirements.

Provisions to be IncludedXAddressed in the Agreement

15. Agreement regarding permissible future uses of the SunriseLandfill which are consistent with maintaining the long-termintegrity and effectiveness of the final closure,40 C.F.R. section 25B.61(c) 3

16. Compliance with Requirements of Applicable Law including:

a. Resource Cgr^servaticn and Recovery Act - construction ar.dmaintenance of the effectiveness and integrity of an appropriatefinal cap or cover, groundwater monitoring, air monitoring, surfacewater controls, post-closure care, financial assurance, and orother 40 C.F.R. Part 258 requirements;

b. Qlean Mr Act - methane and non-methane gas emissions,securing a 40 C.F.R. Part 70 operating permit;

c. Clean Water \ct - Protection of groundwater and surfacewaters ,of the State;

d. ^ndanaered Species fret - Requirements for Desert Tortoiseand other impacted species (Bear Poppy);

e. National Environmental Policy Act - NEPA corrplianceretired for portions of closure not already assessed such asconstruction of methane gas collection system and gas-energy plant,off-lease portion of landfill;

f.. Recreation an^ Pyblie Purposes Act - Renewal of leasesto cover closure and post-closure care time frames;

g. Federal Land Policy and Management Act - DesignatedWilderness Instant Study Area threatened by off-site portion oflandfill and potentially, run-on controls;

h. tfevada Annotated Codes - NDEP, CCHD;

i. CJ.ark County Air Pollution Control Regulations - CCHD;

j. EPA Guidance Documents - All work must comply with EPAguidance documents or ASTM standards.

17. Access to the Sunrise Landfill for all parties to theagreement.

18. Control of public access for health and safety reasons.

19. Interim on-site work should be performed in consultation withappropriate regulatory oversight,. and not be inconsistent withclosure activities.

Concepts for Technical Requirements

20. Workplans - All activities involving, but not limited to, thecharacterization, maintenance, monitoring or modification of thelandfill must be pre-approved by NDEP, Clark County Health Districtand BLM. All field work associated with this requirement mustconform with ASTM and, or EPA procedures.

21. Field Work and Oversight - Clark County Public Works is toprovide prior notification to and secure approval from Clark CountyHealth District, BLM and NDEP for any deviations or modifications

to an approved workplan.

22. Ongoing Reporting Requirements - Monthly Progress Reports forall activities relating to the characterization, maintenance,monitoring, and, or modifications to the 5ML .T.ust be delivered toClark County Health District, ELM and NDEP for review and approval.

23. Characterization of Adjacent Desert Tortoise Habitat - ClarkCounty Public Works will conduct a tortoise survey and instituteappropriate protective measures as outlined in the RtPP lease NEV-046208 stipulations. Clark County Public Works must coordinatethese efforts with BUI and U.S. Fish and Wildlife as appropriate.

24. Interim Landfill Maintenance Plan - Clark County Public Worksis to prepare a workplan, for approval by Clark County HealthDistrict, ELM and NDEP, addressing interim landfill maintenanceissues that may arise. Clark County Health District, ELM and NDEPmust be notified prior to any activities covered in this agreement.

Additional Concept Areas Needed

25. Site Health and Safety Plan/monitoring retirements

a. Site worker safety - OSHA H2S monitoring for onsite work(onsite alarm, worker training).

26. Dispute Resolution.

27. Technical Subcommittee.

28. Community Relations Plan.

29. Cost Reimbursement for oversight activities.

30. Remediation Funding.

31. Definitions.

32. Deed Restriction.

Potential BLM Actions

33. BLM will work with Clark County to transfer* title toleased/off-lease areas comprising the Sunrise Landfill to ClarkCounty.

34. In cooperation with local law enforcement authorities, BLMwill also patrol the landfill.

35. In cooperation with Clark County Public Works, 2LM will ass.stin posting and maintaining access restriction signs ror thelandfill.

p

, 'tt "•'-.;->''"

Groundwater Monitoring PlanSunrise Mountain Landfill

Clark County, Nevada

Prepared for

Republic Silver State Disposal Service

February 10,1999

CH2MHILL3 Hirtton Centre Drive, Suite 200

Saota Ana, CA 9Z7C?

I —7—

I * r - - : 2 « * 3 3

g Groundwater Monitoring Plan# Sunrise Mountain Landfill*, Clark County, Nevada*iii

Prepared for

Republic Silver State Disposal Service

February 10,1999

CH2MHILL3 Hutton Centre Drive. Suite 20C

Santa Ana. CA 92707

••

I

1

I

2

Contents

1

1. Introduction—. —...«-..»-̂ . .̂ _ . —....1-11.1 Objectives of the Subsurface Investigator, .....1-11.2 Site Conditions 1-1

1.2.1 Geology 1-21.2.2 Groundwaier Conditions 1-21.2.3 Groundwater Quality 1-2

2. Scope of Field Investigation.-— ~.»~ __.....—..,...—~. 2-12.1 Well Locations and Depths 2-12.2 Use of BUM Data to Assist in Well Locations 2-3

3. Monitoring Well Installations ........ — ~~m.~~~^ __ ~.~ .......... — .~~.~ ................. — 3-13.1 Drilling and Soil Logging ......................................................................................... 3-1

S 3.2 Well Screen Intervals ................................................................................................ 3-13.3 Well Construction and Completion ........................................................................... 3-23.4 Well Development .................................................................................................... 3-2

^ 3.5 Decontamination Procedures .................................................................................... 3-2

4. Ground water Sampling Procedures........ — ...«..........—...«......—.......... ............... ............. .4-14.1 Groundwater Sampling ............................................................................................. 4-14.2 Request for Analysts ................................................................................................. 4-14.3 Quality Assurance /Quality Control .......................................................................... 4-24.4 Sample Handling, Packaging, and Shipping ............................................................. 4-2

5. Waste Management........ .........„.....-.....„...........„.........„.........,.......„...........„......-.....— .~5-l

••*•••«•««.*•«•«.•••«•««»••.«*««..«•—•......•...«.•«•«.........«..•..*...........«.•.»....•« ...........................D- Jt

Tables

1 Proposed Groundwater Monitoring Wells ....................................................................... 2-22 Groundwaier Sample Analytical Methods, Containers. Volumes, Preservation and

Holding Times ..................................................................................... 4-2

Figures

1 Locations of Landfill and Offsite Wells2 Locations for Monitoring Well Locations

SCCVUU. 1CH2.00GS9W 100E

i»l

1. Introduction

This Groundwater Monitonng Plan for the Sunnse Mountain Landfill in Clark County. Nevada, hasbeen prepared for Republic Silver State Disposal Service (RSSDS). The Sunnse Mountain Landfill isa closed municipal landfill that is located on property owned by the U.S. Bureau of LandManagement (BLM). The property was leased for the purpose of a landfill by Clark County and v-asoperated under contract with Clark County by DUMPCO. a subsidiary of RSSDS. The SunnseMountain Landfill was closed in accordance with the Closure Plan dated Apnl 14. 1994. Figure 1shows the location of the Sunrise Mountain Landfill.

1.1 Objectives of the Subsurface InvestigationRSSDS is conducting a field investigation of groundwater quality adjacent to the Sunrise MountainLandfill (Landfill) as pan of a cooperative effort to assess the potential impact of a release to regionalgroundwater from landfill refuse.

The specific goals of this investigation are:

• Collect subsurface information to identify lithology of subsurface geologic materials in thevicinity of the Landfill.

• Install a sufficient number of groundwater monitoring wells at the perimeter of the Landfill tomake an initial assessment of the potential impacts of the Landfill on regional groundwaterquality.

• Complete a brief 4-hour aquifer tejt or slug test of two of the monitoring wells to estimate thehydraulic conductivity of the in-siru geologic formation in which the wells are completed.

• Collect a sample of groundwater from each new well quarterly for one year and analyze forAppendix 1 constituents listed in 40 CFR Pan 258.

1.2 Site ConditionsThe Sunrise Mountain Landfill is located east of Las Vegas. Nevada at the end of Vegas ValleyDrive. The total area of the land leased from BLM is 720 acres.

The Landfill is located on the eastern edge of Las Vegas Valley, immediately south of FrenchmanCanyon. The uppermost ponion of the Landfill is located within the canyon directly east ofFrenchman Mountain, however the majority of the Landfill is located on the large alluvial fan thatoriginates at the mouth of the canyon and spreads out into the adjacent valley. Elevations range from2.275 to 1.900 feet above mean sea level (MSL).

The climate in Las Vegas Valley is semiarid with a mean annual precipitation of approximately 4.3inches. The annual rainfall is normally concentrated in four or five storms per year, with the majorityof these storms having high intensity and short duration.

1.2.1 GeologyThe sue is mostly underlain by alluvial sediments consisting of a sarficial 4 to 6 foot ( f t ) layer ofloose sand and gravel material underlain by more consolidated gravel and cobbles in a silt and fin?

I1

sand matrix to a depth of about 30 feet below ground surface (ft bgs). Inieriayered within the coarseand fine grained deposits are 5 to iO-ft-thick beds of cemented sand and gravel. At about 20 to 30 ftbgs. fine-grained claystone. siitstone. and sandstone deposits of the Muddy Creek Formation occur.The fine-grained deposits of the Muddy Creek Formation underlie the southern portion of the landfill.

The Sunrise Mountain Landfill lies on the boundary between alluvial valley fill sediments of the LasVegas Basin to the south and bedrock of ihe Frenchman Mountain to the north. The northeasternportion of the landfill property, north of the fault, is underlain by reddish-brown sandstone bedrockand light-colored limestone-dolomite. The center portion of the upper site canyon and lower easternslopes are underlain by the sandstone while steep upper side slopes are underlain by limestone. Thesandstone and limestone are separated from alluvial deposits to the south by a steep fault along thebase of Frenchman Mountain.

•

1.2.2 Groundwater ConditionsGroundwater is present at an estimated depth of approximately 160 to 230 ft bgs at the southern andwestern property boundary of the landfill, and is reported to occur in the Muddy Creek FormationBased on interpreted groundwater levels in the vicinity of the Landfill, the hydraulic gradient in thevicinity of the Sunrise Mountain Landfill is to the west and southwest towards the Las Vegas Wash.Emcon (1986) estimated an average linear groundwater velocity of 1 to 10 feet per year within theMuddy Creek Formation based on a hydraulic conductivity of 10'3 to 10"* cm/sec, a hydraulicgradient of 0.004. and an effective porosity of 30 percent. The hydraulic conductivity value used wasestimated from a well completed within the Muddy Creek Formation 5 miles west of the Landfill.The actual hydraulic conductivity beneath the landfill is anticipated to be less than that based on theslow recovery of previously existing Well B at the Sunrise Mountain Landfill.

1.2.3 Groundwater QualityGroundwater quality to the southwest of the Sunrise Mountain Landfill in the vicinity of the LasVegas Wash is poor. The Total Dissolved Solids (TDS) content of wells LG-34, LG-184, LG-223,and LG-224 ranged from 3404 to 13.444 mg/L in I98S (Emcon, 1986). A sample of groundwaterfrom Well B at the Landfill contained 3684 mg/L TDS.

During September 1998, groundwater samples were collected at existing groundwater wells and at aspring located along the fault southeast of the landfill. No organic compounds were detected ingroundwater or spring samples, or in leachate samples collected from the landfill. TDS concentrationsdetected in groundwater collected from existing wells and springs during the recent sampling episodearc illustrated in Figure 1.

Wells LG223 and LG224. located approximately 2 miles south of the landfill were sampled onSeptember 18 and 22, 1998, respectively, by Converse Consultants West. The samples were analyzedfor volatile organic compounds (VOCs), select inorganics, and total dissolved solids (TDS). A watersample was also collected on October 1, 1998 from a water tank used to store water from a welloperated by Nevada Ready Mix. The well is located approximately 2 miles west of the-iandfill. NoVOCs were detected in the sample.

A sample was also collected from an existing spring along the Sunrise Mountain Landfill Fault. NoVOCs were detected in the sample. The Southern Nevada Water Authority has hypothesized thatleachate from the landfill could potentially travel along the fault and surface at springs along the fault.This spring was sampled to test that hypothesis. Because no VOCs were detected in the sample fromthe spring, there is no evidence that a release has migrated to the spring.

SCOV.llf.J 000790*10032

•NTROOUC-TV

I

I

I\IIi12SIi*Ii

A leachate sample was collected from the landfill on September 22. 1998. This water samplerepresented surface water that flowed into the municipal solid waste and then back into the channeldue to localized erosion of a surface water drainage channel. No VOCs were detected in this sample.

SCOV.I.-.312DOOS9W1COCJ

2. Scope of Field Investigation

The proposed scope of work for this field investigation is as follows:

• Install six downgradiem groundwater monitoring wells at the landfill property perimeter and asclose to the waste as practicable.

• Instill 1 or 2 monitoring wells upgradiem of the Sunrise Mountain Landfill within the canyondirectly east of Frenchman Mountain and drilled to the depth of bedrock only.

• Complete an aquifer or slug test at two of the wells to provide an estimate of in-siru hydraulicconductivity

• Complete a full round of water level measurements from all new wells quarterly for one year.

• Collect quarterly groundwater samples from each completed monitoring well for one year andanalyze for compounds listed in Appendix I of 40 CFR Pan 258 as well as chlonde. nitrate, andIDS at a state<enified analytical laboratory.

Table 2 presents the proposed request for analysis, and sample collection and laboratory analysisr •quirements, respectively.

The following sections describe the field and analytical methods/procedures that will be followedduring the field investigation.

2.1 Weil Locations and DepthsSix groundwater monitoring wells will be installed down gradient of the Sunrise Mountain Landfillnear the Landfill property boundary. This number of wells will provide the data needed to make aninitial assessment of the potential impacts from the landfill to regional groundwater. One upgradientmonitoring well will be installed upgradient of the Sunrise Mountain Landfill within the valley east ofFrenchman Mountain. If difficulty is encountered in completing an adequate upgradient well, asecond upgradient well may be installed. An attempt will be made to install each well screen acrossthe water table. The required well depths at the landfill boundary have been estimated to range fromapproximately 180 ft bgs to 280 ft bgs. Figure 2 shows the locations of proposed groundwatermonitoring locations. Table 1 presents a summary of the proposed well depths.

The location and depths of wells were selected based on the following criteria:

1. Groundwater flow from the landfill appears to be predominantly to the west and southwest r -on water level data provided in the Emcon (1986) report These water levels were consists-additional water level data obtained from the Southern Nevada Water Authority (SNWA

2. The six down gradient monitoring wells are evenly distributed along the landfill perimeu :approximately one-half mile intervals.

3. Well locations were sited within the property limits of the Landfill. Locating the *Landfill property greatly simplifies site access fo: drilling and future monitoring

4. In general, wells were located adjacent to surface washes and historic drainage •rationale for these locations is that the washes may represent preferential pathv

SCOMJ.10120CCWW10COJ

2 SCOPE OF RELD lNVEiTiG«iv>

migration of leachate. if it is being generated at the Landfill. The wells were not located directlywithin the washes due to nsk of the well being inundated and contaminated with surface water, ordamaged due to the potential for high surface flow during high intensity rainfall events.

5. Wells will be completed to a depth that is approximately 30 to 40 feet deeper than the estimatedelevation of the regional groundwater table based on water level data obtained from the SouthernNevada Water Authority (SNWA), as summarized in Table 1. A 20-foot well screen will becompleted within the Muddy Creek Formation as close to the water table as possible given theanticipated difficulties in determining the depth of the water table during drilling. The totalboring depth is assumed to be approximately 30to 40 feet deeper than that estimated from thedepth to water to account for the uncertainty in the depth to water.

TABLE 1. SUNRISE MOUNTAIN LANDFILL CLARK COUNTY, NEVADAProposed Gfoundwater Monrtonrtg Wells

WellNumber

1

2

3

- 4

- 5

6

- 7

8

GroundSurface

Elevation((•«»[1]

1940

1900

1890

1875

1920

1980

2400

2400

EstimatedGroundwater

Elevation<»»*t) (a)

[2]

1780?

1760

1740

1730

1730

1740

unknown

unknown

EstimatedDepth to

Groundwater(tot)

I3W1M2]

160

140

150

145

190

240

unknown

unknown

EstimatedDepth of

Monitoring Well<t«et)

[4W31+40 feet

200

180

190

185

230

280

60

80

Comments

Downgradient well, depthto groundwater uncertainat this location

Downgradient well

Downgradient well

Downgradient well

Downgradient well: samelocation as abandonedWellB

Downgradient well

Upgradient well

Upgradient well installed ifWell No. 7 is unsuccessful

(a) Groundwater elevations trom estimated water level contouring provided by SNWA; assumes elevation1730 lasi at WellB.Well locations shown on attached Figure 2.

2.2 Use of BLM Data to Assist in Well LocationsAvailable boring logs from Emcon (1986) and interpretations included in A Preliminary ElectricalResistivity Survey of the Sunrise Mountain Landfill (BLM. NARSC. August 19. 1998) were evaluatedto determine if monitoring well locations could be specified that targeted potential permeablesubsurface pathways. Specific targets could not be identified, therefore, the downgradient welllocations were selected to provide a broad coverage downgradient of the Landfill.

The resistivity survey conducted by the BLM involved the use of Schlumberger soundings, where anelectrical current is induced into the ground and the electrical field created by the induced current ismeasured. As the spacing of the electrodes that induce the current are increased, the effective dsptr.

SCONJL101Z.90C/W0410CC2 1-2

? SCOPE OF FIELD INVESTIGATION

of the electrical field is increased. Apparent resistivity is measured as the electrode spacing isincreased. Sounding results are evaluated by assuming the subsurface is comprised of horizontallayers with uniform electrical resistivity. A computer model is used to generate a curve of apparentresistivities based on an assumed configuration of horizontal layers, with each layer having a uniformelectrical resistivity. The model is used iteratively until the model-generated results are similar ;oobserved conditions.

The geology of the Sunrise Mountain Landfill area is characterized by alluvial fan depositsunderlying sedimentary bedrock with superimposed faulting. This complex geologic setting isconducive to a high degree of lateral variability in lithology. Consequently, the assumptions used ininterpreting the results of the Schlumberger soundings will likely be violated, and the interpretationsmay be erroneous. However, the sounding results can provide useful data on large-scale variationsfrom one sounding location to another. NARSC conducted this analysis and presented a series ofcross sections in the report. Two general types of interpretations of sounding results are presented:one based on lateral variation being due to faulting, and another where lateral variation is due todepositional variability (i.e., facies changes).

The inteipreted soundings postulate that there is a high resistivity layer (i.e.. greater than 1,000 ohm-meters) underlying the landfill that dips down slope away from the landfill. Resistivity this high istypically indicative of clean sand or gravel (i.e.. potentially high permeability). This unit is interpretedto extend below the water table. Consequently, this unit, if present, could be a potential pathway forpreferential groundwater migration. If faulting is present, however, the fault-gouge zones may act as abarrier to groundwater flow. At the toe of the landfill, this unit is interpreted to be approximately 200feet below ground surface.

This high resistivity unit is not apparent in previous borings at the Sunrise Mountain Landfill. Mostof the previous borings were shallow (less than 100 feet); however Well B was drilled to depth of 315feet and the drillers log reported clay from 120 feet to 315 feet. If a thick, laterally continuous,permeable unit were present at depth, existing wells in the study area should have encountered thiszone, but none have been reported. The proposed groundwater monitoring wells at the Landfillproperty boundary are deep enough to encounter this stratigraphic unit, if present.

The resistivity survey does not provide the resolution to identify small-scale features such as channeldeposits that could serve as conduits to leachate and groundwater flow. Thus, the survey does notprovide additional information that would alter the currently proposed monitoring well locations.

3. Monitoring Weil Installations

The purpose of installing groundwater monitonng wells is to characterize the subsurfaceenvironment, collect groundwater levels used to assess groundwater flow directions, collectgroundwater samples to assess the potential impact of the landfill en downgradient groundwaterquality, and to provide estimates on aquifer hydraulic properties.

3,1 Drilling and Soil LoggingThe monitoring well boreholes will be drilled using a direct air rotary drilling rig. During drilling ofeach monitoring well borehole, drill cuttings will be collected and logged at S-foot intervals and/crnoticeable changes in lithology to characterize the geology and identify potential pathways formigration of leachate away from the landfill. The soil cuttings samples will be logged using theUnified Soil Cassification System (U5CS) as described in American Society for Testing andMaterials (ASTM) Standard D 2488-84. The presence of moist or saturated intervals will beidentified.

The borehole will then be overreamed to an 8-inch diameter for well construction. An experiencedfield geologist/engineer will observe drilling activities, and prepare borehole logs and wellconstruction reports under the supervision of a registered geologist/engineer.

In response to BLM's suggestion, continuous coring of the bottom of each borehole was evaluated asa means of providing more detailed information of the subsurface lithology in the vicinity of thetargeted well screen interval. In order to core the bottom of the borehole, the use of drilling mudwould be needed. Given the vtry slow recharge rate of the two previously existing groundwatermonitoring wells at the Sunrise Mountain Landfill, and the very-fined grained texture of the deepersediments, the use of mud, even if polymers are used, may potentially partially plug off the boreholewall and significantly reduce the rate at which the monitoring wells recharge. It is already anticipatedthat well development may be difficult in this environment. Therefore, although this procedurewould provide additional valuable information, it is considered too risky to use at this time.

Groundwater monitoring well permits will be obtained, and both the Clark County Public WorksDepartment and NDEP will be notified prior to the start of drilling.

3.2 Well Screen IntervalsThe monitoring wells will be constructed with 20-foot well screen intervals. The depth togroundwater at the downgradient boundary of the Sunrise Mountain Landfill is estimated to rangefrom approximately 140 to 190 feet, but very little data are available in the vicinity of the Landfill.Based on the previous experience at the Sunrise Mountain Landfill, the depth to groundwater may bevery difficult to determine during drilling, due to the slow rate at which the wells recharge. In 1986.the groundwater level in Well B recovered to only 25 percent of its initial height after 9 days, due tothe very low hydraulic conductivity of the Muddy Springs Formation. However, an attempt will bemade to install the well screen about 5 ft above and IS ft below the water table. Close examination ofthe core that is recovered at the anticipated depth of the water table will be used to target permeablepathways of groundwater flow and possibly to help estimate the depth of the water table. The degreeof saturation of the core may be difficult to assess due to the very fine-grained texture of thesediments.

SCOM11012.00C«9M lOOOI

: WQHrroww WEU KSTALUTONS

3.3 Weil Construction and CompletionThe proposed groundwater monitoring wells will range in depth from approximately 80 to 300 feet.All the wells will be constructed using 4-inch-diameter, Schedule 80 polyvinyl chloride (PVC)casing, with 20 feet of slotted PVC well screen. A 5-foot length of PVC casing will be installedbelow the well screen to act as a sediment trap. The first monitoring well will be completed with0.07.0-inch sionsd well screen and 12x20 Monterey sand or equivalent. Based on the grain sizedistribution of soil samples encountered during drilling, the onsite field geologist may specifyalternate well screen slot sizes and filter pack gradations for the remaining wells. Filter pack will beplaced in the annular space adjacent to the well screen up to about 5 above the top of the well screen.Bentonite chips or pellets will be placed in the annular space above the filter pack to form a minimum2 ft thick sanitary seal. The remainder of the annular space will be pressure grouted to the surfaceusing a tremie with a 5 percent bemonite grout mix. All the wells are anticipated to be above-gradesteel-cased completion, with four above ground bumper poles set in a concrete pad.

The locations of the monitoring wells will be surveyed, and tied to locally available monuments.Landfill property lines, and downgradiem extent of fill will be surveyed and shown with the we!!locations on a scaled plot plan.

3.4 Well DevelopmentWell development will be accomplished by the following procedures:

Initial development using a surge block, and bailing as necessaryFinal development using a temporary submersible pump

Measurements of pH. temperature, and electrical conductivity (EC) will be recorded during welldevelopment. The development process will continue until field parameters stabilize or ten casingvolumes have been removed from the well, whichever occurs first, or until the well has beendswatered and has recharged twice and field parameters appear to be stabilizing. Based on existinginformation regarding water yield in the Muddy Creek Formation, it is anticipated that the monitoringwells will bail dry quickly and that considerable time (more than 24 hours) may be required for thewell to recharge.

3.5 Decontamination ProceduresPrior to transporting the drill rig and support equipment on site, the rig, augers, drill rods, and otherequipment that will be used downhole will be steam-cleaned. The drill rig and downhole tools will becleaned in the same manner after installation of each well.

Well construction materials such as the PVC blank casing and well screen will be supplied as newmaterials, free of solvents, oils, or any foreign matter, and will undergo a high-pressure steam rinseprior to installation.

Well development and soil and groundwater sampling equipment will be decontaminated prior to useat each sampling location. Some of this equipment includes the surge blocks, pumps or bailers andmiscellaneous field equipment. The following decontamination procedures will be observed:

1. Wash with tap water, using a brush if necessary

2. Wash with Alconox. or a phosphate-free detergent, and tap water solution, using a brush ifnecessary

3. Rinse with up water

4. Rinse with deionized or distilled water

5. Air dry

4. Groundwater Sampling Procedures

m

This section provides the procedures for groundwater sampling, the requested analyses forgroundwater. QA/QC samples, and sample handing, packing, and shipping.

4.1 Groundwater SamplingGroundwater samp'cs will be collected in genera! accordance with the following procedures:

• After well development, the wells will be allowed to stabilize for a minimum of 24 hours or untilthe well has fully recovered to static groundwater conditions before sampling.

• The static water level will be measured in each well using a well sounder.

• Based on the static water level, the volume of water in the well casing will be determined.

• The well will be purged of three (3) well volumes or dewatered twice prior to sampling using amild steel or disposable bailer, bladder pump, or submersible impeller pump.

• If wells are purged with a bladder pump or Redi-Flow 2 pump, the pumping rate will be reducedto 200 milliliters per minute prior to sample collection in order to minimize the potential loss ofvolatile organic compounds (VOCs). If the wells are purged dry prior to sampling, then, after thewell has recharged, the samples will be collected using disposable bailers. Care will be takenwhen filling the 40-ml VOA vials to minimize air contact and any turbulence of the samples inorder to prevent loss of VOCs. Samples will be placed in appropriate laboratory-suppliedcontainers and packed in ice for shipment to the off-site fixed laboratory.

• Field measurements (i.e., pH, temperature, and electrical conductivity [EC]) will be collected.

• Purging and sampling information will be recorded in the field log. Information recorded willinclude, at a minimum, well number: date: times of purging and sampling: water level and fieldmeasurements: volume calculations: and total volume purged.

4.2 Request for AnalysisGroundwatei samples will be collected from the seven or eight new wells. The samples will be sen:to an off-site, fixed Nevada state-certified laboratory. Each sample will be analyzed for the EPAAppendix I constituents including VOCs by EPA Method 8260 and metals by EPA Method 6010, aswell as total dissolved solids (TDS), chloride, nitrate, pH. temperature, and specific conductance. Asummary of the sample analyses, analytical methods, required containers, sample volumes, samplepreservation, and holding times are provided on Table 2.

4.3 Quality Assurance /Quality ControlQuality Assurance/Quality Control fQA'QC) samples will be collected including blank samples (tri;equipment, and ambient blanks), matrix spike/matrix spike duplicate (MS/MSD). and duplicatesamples. One duplicate sample, one MS/MSD. and one complete blank sample (for all anaiytes) will

SCQVU1012.DJCW041KW

4 CfiOUNOWATTP SWUNG PROCsOUflES

be taken during the sampling of all 5 or 6 wells. In addition, a VOC tnp blank and a VOC ambientblank will be taken each day a VOC sample is collected.

TABLE 2Grounq^ater Sample Analytical Method?. Containers. Volumes. Preservation, and Holding Times

Analytical Group

47 VOCs

15 Metals

Chlorite

Nitrate

Total Dissolved Solids

PH'

Temperature

Method Number

EPA 6260

EPA 60 10

EPA 300.0

EPA 300.0

EPA 160.1

EPA 150.1

EPA 170.1

Container

G, Teflon-linedseptum

P

P

P

P,G

P. G

P. G

MinimumSampleVolume

3x40-mLvials

1 x 500-mlbottle

1 x1L bottle

1 x1L bottle

1 x1L bottle

N/A

N/A

Preservation

HCI, pH<2. 4°C;

no headsoace

HNO3, pH<2.4°C

Cool to 4°C

Cool to 4°C

Cool to 4°C

None required

None required

Maximum HoldingTime

14 days

€ months

28 days

28 days

28 days

Analyzeimmediately inlaboratory

Analyzeimmediately inlaboratory

Notes:P - PolyethyleneG - GlassN/A - Not Applicable

4.4 Sample Handling, Packaging, and ShippingDuring this investigation, water samples will be collected for laboratory analysis. Water samples tobe analyzed will be packaged in containers provided by the analytical laboratory. Analyticalmethods, sample containers, volumes, preservation methods, and holding times are summarized inTail: 2. These containers will include: 40-ml glass vials. 1-liter amber glass bottles, and/orpolyethylene bottles (500-ml and 1-liter). The 40-ml vials containing samples to be analyzed forVOCs will be wrapped together with bubble pack and secured with strapping tape after assuring thatno air bubbles are present. Each bubble-wrapped 40-ml vial pair wil] then be placed in zip-lockplastic bags. AH other glass bottles will be wrapped in bubble pack and placed in separate zip-lockplastic bags. Polyethylene bottles will be placed into zip-lock plastic bags.

AM water samples will be stored on ice in coolers immediately after collection and packaging. Thecoolers will contain double-bagged ice packages to maintain a sample temperature at 4°C. Prior toshipment, the empty spaces in the cooler will be filled with bubble pack to prevent sample containerbreakage or movement. A Chain-of-Custody Record will be placed in a zip-lock plastic bag andtaped to the inside of the cooler lid. The cooler will be taped shut with strapping tape, and at leas;two signed custody seals will be affixed over the lid openings to allow the cooler recipient todetermine whether the cooler has been opened. Clear tape will be placed over the custody seals toensure that the cu^iod) seals are not broken accidentally during shipment. Coolers will be shipped :othe designated laboratory.

SCOVJ.1012.DOC/99M100C2 4-;

5. Waste Management

Three types of waste materials will be generated during the fielu activities. These waste materialsinclude: 1) decontamination water. 2) drill cuttings; and, 3) well development/purge water.

Soil cuttings will be containerized in a 20-yard roll-off bin. The bin will be temporarily labeled a?nonhazardous waste, and marked "awaiting analytical results". If the analytical results ofground water indicate the possible presence of contamination at the monitoring well locations, thenthe soil cuttings will be laboratory analyzed to characterize the waste for disposal. If groundwatersample analytical results do not indicate the presence of groundwater contamination, the soil cuttingswill be considered nonhazardous and will be disposed of at an appropriate landfill.

Decontamination water, well development, and sample purge water generated during the fieldactivities will be collected and held. The decontamination water will be profiled and disposed ofbased on analytical results from the groundwater samples collected during the field activities. Ifanalytical results indicate that the groundwater samples are hazardous, the decontamination water willbe disposed of as hazardous waste. Otherwise, the decontamination water will be disposed of as anonhazardous waste.

SCOAJIU012 DOC/S904100Q2 6-1

6. References

EMCON Associates. December 1986. "Sunrise Mountain Landfill Expansion. Clark County,Nevada." Prepared for Dumpco. Inc.

Bureau of Land Management, National Applied Resources Sciences Center. August 19.1998. "APreliminary Resistivity Survey of the Sunrise Mountain Landfill."

Desert Research Institute (DRI), Water Resource Center. October 15, 1998. "Groundwater QualityImpacts of Sunrise Landfill."

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RECORD OFCOMMUNICATION

DISCUSSION

PHONE CALL

:ONFERENCE

OTHER (SPECIFY)Site visit

(RECORD OF ITEM CHECKED ABOVE)

TO: Sunrise LF File FROM: David Emm ief, 3WM DATE:10/2/98

TIME:

SUBJECT; Summary cf findings during 9/29/98 site visit to Sunrise LFSUMMARY OF COMMUNICATION:The purpose of our site visit was to inspect damage to the site resultingfrom the Sept. 11, 1998 storm event. Les Gould, Nadir Sous and myself drov*to the Sunrise LF gate with Ed Wojcik, CCHD. We were me.t at the gate by BobGroesbeck, Alan Gaddy and Jim Rankin from Republic Silver State. We visiteda damaged area on the NW part of the landfill near the asbestos disposal areathat was being repaired and regraded, substantial erosion of the cap hadevidently occurred. Alan Gaddy indicated that their on-site rain gauges hadcollected 2.0, 2.2 and 2.5 inches of rain from the event in less than anhour. Bob Groesbeck indicated they had someone on-site during the rain event.We drove to the upper lift and along the eastern drainage ditch and noted thegas vents on the sideslope and erosion of the east drainage ditch. A lengthof a few hundred feet or so of the lined ditch had completely washed away anderoded underlying trash, this area had also been recently covered with soil.Also on the upper lift the stormwater system had completely failed, allowingrunoff to drain over the south edge of the upper lift cutting deep rills intothe sideslope. We drove to the northern limit of the landfill and noted anarea where water had ponded at the entrance to the east drainage ditch, thehigh water mark indicated the depth may have been 4-6 feet. Alan Gaddyspeculated that the entrance to the ditch had become clogged with debris,forming a dam which ultimately failed sending a slug of water down thedrainage ditch. There did not seem to be any evidence to support thisscenario, ie. indicating a sudden release of a wall of water. Instead itsimply appeared as though the stormwater backed up behind the drainage ditchbecause the water was coming too fast for the ditch to carry it all away. Wethen drove to the outlet of the drainage ditch along a bedrock canyon at theSE edge of the site and observed where flood waters had eroded waste andscoured a channel in the bedrock. Vic Skaar and Shane Martin, CCHD werecollecting water samples from two small ponds of water that appeared to bestormwater draining from the waste and from fractures in the bedrock. AlanGaddy said they had sampled these pools and found no organic contaminants. Itwas obvious the pools had been drying up since the storm event. We couldalso see Republic's crew a mile or more away, toward Las Vegas Wash, pickingup garbage that had washed away in the flood event. Before we left, Iindicated to Bob Groesbeck and Alan Gaddy that we would likely rssue an Orderto ensure that the drainage system was re-evaluated and if necessaryredesigned. I acknowledged the significant level of clean-up and repair workthey had done given the extensive damage. They indicated they already hadtheir consultant working on an evaluation of the stormwater system and anOrder was not needed. We disagreed on this and left the site.

CONCLUSIONS, ACTION TAKEN OR REQUIRED: Discuss with Verne, Allen.

ROUTE TO: 1. 2. FILE: Sunrise LF_