SDMSDocID 2027681

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SUNRISE LANDFILL CLEANUPFIELD INVESTIGATION REPORT

2027681

PBSI901 NORTH GREEN VALLEY PARKWAY >^^SUITE 100HENDERSON, NEVADA 89014-6139TELEPHONE: 702/263-7275 FAX: 702/263-7200

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SUNRISE LANDFILL CLEANUPFIELD INVESTIGATION REPORT

2027681

Prepared for:

I REPUBLIC DUMPCO, INC.770 East Sahara Avenue

Las Vegas, Nevada 89014

IPrepared by:

I PBS&J901 North Green Valley Parkway Suite #100

Henderson, Nevada 89014

* Reference Number 511047

I June 9,1999

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June 9,1999

Mr. Alan J. Gaddy, M.S. CEMVice PresidentREPUBLIC DUMPCO, INC.770 East Sahara AvenueLas Vegas, Nevada 89014

RE: SUNRISE LANDFILL CLEANUP FIELD INVESTIGATION REPORTPBS&J REFERENCE NUMBER 511047

Dear Mr. Gaddy:

PBS&J has enclosed two copies of the Sunrise Landfill Cleanup Field InvestigationReport for your final review and submission to the Environmental Protection Agency(EPA). If you or the EPA have any questions or comments, please do not hesitate tocontact us (702/263-7275).

Sincerely,

Mark A. Sorensen, P.E.Manager-Drainage Services

cc. Tom Gardner

PBSV?

Sunrise Landfill Cleanup 6/9/99Field Investigation Report

TABLE OF CONTENTS

I. INTRODUCTION 1

litH. GENERAL INFORMATION 1

A. Site Location 1

B. Project Description 1

C. CCRFCD Master Plan Information 3

f D. FEMA Floodplain Information 3

E. PBS&J Experience 6

1 F. Project Assumptions 6H

HI. FIELD INVESTIGATION 7r —- - — • "•• " •• •

I A. Onsite 7

<] B. Offsite 8

IV. CONLUSION 9

V. REPUBLIC DUMPCO, INC. CERTIFICATION 11

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^ Sunrise Landfill CleanupField Investigation Report

1LIST OF FIGURES

™ Figure 1. Area/Vicinity Map

1 Figure 2. CCRFCD Master Planned Facilities Map

_ Figure 3. FEMA Map

Figure 4. Project Boundary Map

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LIST OF APPENDICESI

™ Appendix I EPA's Order of Compliance Figure Al

• Appendix II Photos

Appendix III Resume (Standard Form 255) for Mark A. Sorensen

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Sunrise Landfill Cleanup 6/10/99Field Investigation Report

I. Introduction

PBS&J was contracted by Republic Dumpco, Inc. on May 24, 1999 to perform afield investigation of the results of the trash cleanup on and around the closedSunrise Landfill. The trash was deposited as a result of a September 11,1998 stormwithin washes adjacent to the landfill.

II. General Information

A. Site Location

The Sunrise Landfill site is located within a portion of the northeast quarter(NE 1/4) of Township 21 south, Range 62 east sections 1, 11, and 12M.D.M., Clark County, Nevada (Figure 1).

B. Project Description

PBS&J's contracted assignment was to determine, based on surface fieldinvestigation, if the cleanup efforts had met the intent of Requirement No.21 of EPA's Order for Compliance as reproduced below:

"21. Within 45 days, but no later than June 11, 1999, clean up anyremaining trash and debris on the Landfill, along the large unnamedwash, tributary to the Las Vegas Wash, and within 500 yards of thelease boundary within the South Wash Area, continuing in anycontinuous wash as required to remove visible pocketedaccumulations, and certify the completion of this task to the EPA.All debris shall be disposed of in accordance with all federal, state,and local laws and regulations."

Attachment A-l from the EPA's Order for Compliance is included inAppendix I.

The area of the site reconnaissance included the entire existing landfill siteand the adjacent washes as shown on Figure 4 (excepting the northwestcanyon area and eastern perimeter area shown as double cross hatch).

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Sunrise Landfill Cleanup 6/9/99Field Investigation Report

C. CCRFCD Master Plan Information

Figure 2 shows the subject property in relation to Clark County RegionalFlood Control District (CCRFCD) Master Planned facilities. The exhibitwas reproduced from Figure F-16 of the 1996 CCRFCD Master Plan Updateof the Las Vegas Valley (CCRFCD, 1996). The figure shows that the site islocated near the following facilities:

1. Approximately 7000 ft West of the site.• Las Vegas Wash - Middle

a. LVMD 0819 - 370-ft of Existing Concrete - Channel100'W8'D2:1SS

b. LVMD 0715 - 5,482-ft of Existing Earthen Channel120'W12'D3:1SS

c. LVMD 0715 - 7,964-ft of Proposed 6' High Rock LinedDike on both sides of the wash

d. LVMD 0639 - 4,000-ft of Proposed 6' High Rock LinedDike on the West side of the wash

e. LVMD 0638 - Existing Reinforced Concrete BoxCulverts (2-10'x3', 2-5'xl.8', 2-5'x5'), Proposed 15-8'x8'RCBC at Sanitation Service Road.

2. Approximately 5000 ft Northwest of the site.• Orchard Area Conveyance/Detention

a. SLOR 0170 - 3,000-ft of Proposed Gabion Channel10'W4'D2:1SS

b. SLOR 0142 - 1,500- ft of Proposed Gabion Channel10'W6'D2:1SS

c. SLOR 0138-65 ac-ft Detention Basin with a 14,600 cfsSpillway and a 60" RCP Outlet Pipe

d. SLOR 0085 - 2,650-ft of Proposed 66" RCPe. SLOR 0053 - 1,500-ft of Existing 66" RCP

The site is not directly impacted by any of the above CCRFCD facilitiesthough it does drain toward the Las Vegas Wash - Middle Branch (LVMD).

D. FEMA Floodplain Information

Figure 3 is a reproduction of the Federal Emergency Management Agency(FEMA) Flood Insurance Rate Maps for Clark County, Nevada,Community-Panel Numbers 32003C2200 D and 32003C2225 D, effectiveAugust 16, 1995. The property lies within a flood insurance area designatedby FEMA as Zone X.. Zone X is defined by FEMA as an area determined tobe outside the 500-year floodplain.

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C L A R K C O U N T Y

REGIONAL FLOOD OMFO. DISTRICT

FLOOD CONTROLMASTER PLAN UPDATE

LAS VEGAS VALLEY1996

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PROPOSED MASTER RANFACILITIES

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GRAPHIC SCALE

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(IN FEET)

SCALE: 11NCH = 3000 FEET

FLOOD CONTROL FACILITIES

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FIRMFLOOD INSURANCE RATE MAP

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PANEL 2225 OF 4090(SEE MAP INDEX FOR PANELS NOT PRINTED)

NUMBER PANEL SUFfK

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MAP NUMBER32003C2225 D

EFFECTIVE DATE:AUGUST 16,1995

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FIRMFLOOD INSURANCE RATE MAP

CLARK COUNTY,NEVADA ANDINCORPORATED AREAS

PANEL 2200 OF 4090(SEE MAP INDEX FOR PANELS NOT PRINTED)

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OROE 46

URT 67

: COURT 130

=tY STREET. 180

P STREET 181

RD DRIVE 183

rr 175STREET 186

1ATSWORTH COURT 58

»NTREE CIRCLE 156

pi RICHARD DRIVE 182

IOAN LANE 19

'ROE 38

HILL DRIVE 101

E WAY 61

. WAY 166

TREET .123

«IGE STREET 132

STREET 160

HEIGHTS LANE 148

[IME DRIVE,

HILLS DRIVE 29

COURT 147

CIRCLE 165

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CASCADE STREET 205

!„ CHAMPIONS AVENUE 82

q CHAMPIONS CIRCLE 88

CLAGETT LANE 121

CLARGES LANE 176

CLEEK STREET 72

CLEMENTINE STREET 146

CLOVERLEAF CIRCLE 47

CLUB HOUSE DRIVE 87

COALDALE PLACE 172

COMMODORE COVE DRIVE 30

COMMONWEALTH DRIVE 36

— CONSUL AVENUE 75

COPPER ROAD -62

CORAL VINE WAY J5

CORTINA AVENUE 73

COTTON STREET 178COUNTRY KNOLL CIRCLE -18

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WILD BERRY DRIVE 2

WILLOW OAK CIRCLE 45

WINCHESTER STREET 133

WIND RIVER DRIVE 139

YERINGTON AVENUE 163

901 N. Green Valley PkwySuite 100Henderson, Nevada 89014Telephone: 702/263-7275Fax: 702/263-7200

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Sunrise Landfill CleanupField Investigation Report

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E. PBS&J ExperienceBecause the trash was uncovered and deposited by an extreme stormevent, Republic Dumpco, Inc. and PBS&J believed that field inspectionrelated to Requirement No. 21 of the EPA Order of Compliance wouldbest be handled by an experienced surface water hydrologist. Mr. MarkA. Sorensen, P.E., a registered Civil Engineer with 14 years ofexperience was therefor selected. Most of Mr. Sorensen's career has beenin hydrologic analysis, hydraulic design, and scour mitigation. All of hisexperience has been in the Las Vegas Valley and surrounding areas.

As a drainage engineer, Mr. Sorensen has analyzed the hydrology ofvirtually the entire Las Vegas Valley for such projects as the 1996 ClarkCounty Regional Flood Control District Master Plan and the 1999 City ofLas Vegas City-wide hydrology study. He has analyzed the Las VegasWash and tributaries for numerous public and private drainage studiessuch as the Palm City development, the Clark County Sanitation DistrictCentral Plant Expansion, and the Southwest Gas Line at the Las VegasWash Scour Mitigation Project. These three projects are all locateddownstream of the Sunrise Landfill.

Mr. Sorensen's experience has included driving and hiking most of themajor washes in the Las Vegas Valley to determine basin delineation, soilcharacteristics, and scour potential related to storm flows. This has givenhim knowledge of debris flow characteristics of this area as well as a verygood general idea of the appearance of storm deposited debris and trash asopposed to direct illegal dumping and windblown trash.

A resume for Mr. Sorensen is included in Appendix III.

F. Project Assumptions

PBS&J's field investigation was limited to visual inspection of the post-storm event cleanup efforts within the limits shown on Figure 4 (exceptingthe northwest canyon area and eastern perimeter area shown as doublecross hatch). No subsurface exploration or exploration beyond the limitsshown on Figure 4 was performed. No detailed study of the hydrologicwatershed associated with the storm event was performed. No hydraulicor scour analysis was performed for the flood control facilities built toprotect the closed landfill. No design recommendations to prevent futurescour damage to the closed landfill were made. However, in order tounderstand the performance of the landfill's storm water facilities and thedebris flow patterns, PBS&J made general assessments of the hydrology ofthe area and flood control facilities.

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PBS&J did not inspect the cleanup efforts during its actual occurrence orthe disposal of the collected refuse.

Note that the area downstream of the landfill is still subject to illegaldumping and windblown trash. Also, though many hours of fieldinvestigation were performed and all expected trash flow paths werewalked or driven, some very small and isolated areas between the washesmay not have been seen. And finally, most of the cleanup was necessarilyperformed by hand (for environmental considerations) and no such humaneffort can be 100% effective. Based on the above, PBS&J's finalconclusions must include some engineering judgement.

HI. FIELD INVESTIGATION

A. OnsiteThe first field investigation was performed on May 28, 1999. The entirelandfill site was driven and existing storm water facilities were examined.Also, landfill side slopes were examined. The upstream watershed wasdetermined, in general, by field investigation and use of 1996 GIS aerialtopography. David Faircloth of Environmental Technologies provided firsthand accounts of the flows, drainage, facility performance, and trash scour anddeposition during the storm event.

The flow and trash erosion patterns described by Mr. Faircloth were consistentwith the hydrology of the area and expected scour locations. The downstreamareas identified by Mr. Faircloth where trash was deposited were consistentwith expected patterns.

Note, the major offsite watershed that impacts the landfill is channeled alongthe east side of the landfill to a natural major tributary to the Las Vegas Wash.The improved channel on the landfill site was riprap lined with a gabion gradecontrol structure. A portion of the riprap lining failed during the storm eventaccording to Mr. Faircloth, which is consistent with general velocities andshear forces that would be expected. Though the channel apparently did notmigrate laterally, vertical scour experienced within the northeast canyon areauncovered trash. This was deposited from just downstream of the landfill tothe Las Vegas Wash.

The improved channel discharges to a semi-natural, semi-blasted rock arealeading down to the major tributary. This rock area provides a good amountof grade control/head cutting protection and limits the amount of scourpossible in the improved channel. The channel has been regraded, but notrelined at this time.

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Mr. Faircloth also described minor erosion of the landfill side slopes along thesouth and southwest boundaries of the landfill. Also described was thedamage to some of the half round corrugated metal pipe (CMP) culverts usedto channel onsite flows. The side slopes and CMP culverts have been largelyrepaired. The side slope erosion occurred mostly from onsite flows with someminor offsite flows.

Based on rain gauge data provided by Mr. Faircloth, (over 3 inches for 3different gauges) and the duration of the storm, it appears that the storm mayhave been beyond a 100-year event. Based on the above, the accounts of Mr.Faircloth appear reasonable.

No uncovered trash was observed on the landfill, the west burn pit or themain channel area.

B. OffsiteThe second half of the May 28, 1999 field investigation was performeddriving and walking the major tributary to the Las Vegas Wash. It wasinvestigated from the dump all the way to the Las Vegas Wash. Some illegaldumping was observed including discarded targets and construction debris.However, virtually no trash with the appearance of being the result of stormdeposition was observed. Much of the trash observed was above the highwater mark hi the washes.

The second field investigation was performed on June 2, 1999 and was spentwalking all of the minor washes along the south and southwest boundaries ofthe landfill site. The washes were walked for at least 500 yards beyond thelandfill limits (survey stakes were observed). A significant amount of illegalconstruction and landscaping debris was observed, mostly downstream of thesouthwest corner of the landfill site. Much of this was above the high watermark. Some rusted cans were observed downstream of the south boundary ofthe landfill (towards the west) though they did not appear to be deposited bystorm flows. Mr. Faircloth indicated that this was very old ("pre-landfill")dumping.

Washes along the southwest and south (western half) boundary of the sitewere virtually free of trash with the appearance of storm deposition forthe 500+ yards zone investigated.

Washes along the eastern half of the south boundary of the site werevirtually free of any trash within the 500+ yard wide investigation area.

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However, some finger washes were found that appeared to have had only aninitial clean up effort. A modest amount of trash was observed that had,definite storm water deposition characteristics. Also, some trash bags andbundles, apparently filled but not collected by clean up crews were observed.These areas were identified and Mr. Faircloth agreed to send the clean up crewback out.

The final field visit was performed on June 8, 1999. The washes along theeastern half of the south boundary of the dump were reexamined. Virtuallyno trash was observed.

Site photos (see Appendix II) were taken.

IV. CONCLUSION

The project area investigated includes the landfill site, the major tributary to theLas Vegas Wash from the landfill (east side) to the Las Vegas Wash, and theminor washes along the south and southeast boundaries of the landfill to a point500+ yards downstream of the landfill property line. Illegal dumping andwindblown trash was found however, as of June 8, 1999 virtually no trash thatappeared to be stormwater deposited and originating from the landfill wasobserved. PBS&J believes and herein certifies that (as to visible trash and inconsideration of the project assumptions herein) the cleanup effort meets theintent of EPA's Order of Compliance No. 21.

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V. REPUBLIC DUMPCO, INC. CERTIFICATION

I certify under penalty of law that this document and all attachments wereprepared under my direction or supervision in accordance with a system designedto assure that qualified personnel properly gather and evaluate the informationsubmitted. Based on my inquiry of the person or persons who manage thesystem, or those persons directly responsible for gathering the information, Icertify that the information submitted is, to the best of my knowledge and belief,true, accurate, and complete. I am aware that there are significant penalties forsubmitting false information, including the possibility of fine and imprisonmentfor knowing violations.

Alan J. Gad<|Vice PresidesREPUBLIC DUMPCO, INC.

Dati

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APPENDIX IEPA's ORDER OF COMPLIANCE FIGURE Al

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MAP ATTACHMENT A-1

Sun rise LandfillLas Vegas, NV t

Nellis Air Force Base

McCarran Airport 0.5 1 1.5

Scale: 1:47,874

2.5 Miles

APPENDIX IIPHOTOS

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Landfill Main Drainage Channel (looking upstream)

Landfill Main Drainage Channel at the discharge point (looking downstream)

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Looking toward the Landfill while standing in the Major Tributary to the LasVegas Wash (middle).

Looking toward the Las Vegas Wash while standing in the Major Tributary to theLas Vegas Wash (middle).

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Looking toward the Landfill while standing in the Major Tributary to the LasVegas Wash (near Hollywood Boulevard).

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Looking toward the Las Vegas Wash while standing in the Major Tributary to theLas Vegas Wash (near Hollywood Boulevard).

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L 'Wito. *> jSsS « * • ' £ . a • > > . " isjfeglS « ab" =- > * ;- il^5T ^ •'-' *" ».

: Vsfir^- ", *h: i*^*^t'JL*«|k • V -.^J**-** * ."

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Illegal dumping 700 ± yards downstream of the Southwest corner of the landfill.

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Looking toward the landfill while standing in the south wash area (easterly portion).

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Looking downstream at the south wash area (easterly portion).

Looking downstream at the south wash area (westerly portion).

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Looking toward the Landfill while standing in the south wash area (middle).

South wash area near the 500 yard point (middle)

IIIIIIII. APPENDIX IIII RESUME (STANDARD FORM 255) FOR MARK A.

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7. Brief resume of key persons, specialists, and individual consultants anticipated for this projecta. Name & Title:Mark A. Sorensen, P.E., Senior Project Manager, Drainage Services

b. Project Assignment:Drainage

c. Name of Firm with which associated:PBS&J

d. Years Experience: With This Firm4,5

With Other Firms9.5

e. Education: Degree(s) / Year / SpecializationB.S. /1985/Civil Engineering

f. Active Registration: Year First Registered / Discipline1990/Professional Engineer/Nevada/8742

g. Other Experience and Qualifications relevant to the proposed project:

Mr. Sorensen has more than 14 years of flood control and public utility engineeringexperience including hydrologic/hydraulic analyses, design, and construction management offlood control, sewer, and water distribution facilities. His project experience includes theLake Mead Storm Drain and Carey/Lake Mead Detention Basin, Flood Control Facilities Planfor the Northern Las Vegas Wash, and the Gowan Detention Basin Outfall. He has managedlarge flood control planning projects such as the Southwest Area II Development Guidelinesfor Clark County and Northwest Neighborhood Studies I and II and Citywide HydrologyAnalysis and Facility Inventory for the City of Las Vegas. He has extensive experience withpreparation of cost estimates, construction specifications, and bid documents for flood controland public utility projects. Before joining PBS&J, he was a project engineer for the FloodControl Department of the City of Las Vegas and managed the public works and privatedrainage study review team. He was directly responsible for approval of all drainage studies;review of regional detention basins, open channels, and storm drains; and coordination ofdevelopment drainage issues between the City of Las Vegas, Clark County Regional FloodControl District (CCRFCD), Federal Emergency Management Agency (FEMA), developers,adjacent communities, and the public. Prior to his service with the City, he worked for severalsouthern Nevada civil engineering firms for which he designed sewer and water distributionfacilities and prepared land development drainage studies. His specific project expenenceincludes:

Northwest Neighborhood Studies I and n and Citywide Hydrology Analysis andFacility Inventory, Las Vegas, Nevada. Project manager for these major flood controlfacility planning and hydrologic studies. The citywide study included analysis of the entirewatershed impacting the City, and the neighborhood studies encompassed over 50 squaremiles. All analysis, design, and inventory results are integrated in a GIS database.

Southwest Gas Line at Las Vegas Wash, Clark County, Nevada. Designed erosioncontrol system to mitigate scour and promote revegetation to protect a 24-inch, high-pressure steel gas line along the Las Vegas Wash.

US 95 Beltway Interchange, Clark County, Nevada. Project manager for drainagedesign for this major roadway bridge project. Designed interim box culvert and channelsystem to be compatible with future master plan flood control facilities.

Las Vegas Valley Master Plan Update, Clark County,Nevada. Deputy projectmanager for this flood control master plan for the CCRFCD. The master plan includesapproximately $1 billion in regional drainage improvements including large detentionbasins, storm drains, and open channel. The project involves hydrology for the entire LasVegas Valley watershed, preliminary hydraulic design, facility siting, cost estimates, andfeasibility research. Proposed and existing facilities and hydrologic parameters arepresented in a GIS format.

Southwest Las Vegas Valley Development Guidelines Area n, Nevada. Projectmanager for this drainage master plan for 26 square miles of mostly undeveloped land. Theproject included existing and developed condition hydrologic analysis, existingimprovements inventory, proposed street grade design, development standardspreparation, and proposed drainage facility design. All analysis, design, and inventoryresults are integrated in a GIS database.

Nellis Air Force Base Water System Analysis, Las Vegas, Nevada. As designengineer, prepared FAAST™ computer model of base distribution system, including largetanks and pump stations, and identified deficiencies.

FEMA Northwest Las Vegas Flood Insurance Study (FIS) Restudy, Las Vegas,Nevada. Project manager for the City of Las Vegas' review and coordination of theNorthwest Las Vegas FIS that included hydraulic and hydrologic analyses of a largeportion of the Las Vegas Valley.

Lake Mead Storm Drain and Carey/Lake Mead Detention Basin, Las Vegas,Nevada. Project engineer for the design of the Carey/Lake Mead Detention Basin.Required extensive coordination between City of Las Vegas, City of North Las Vegas,CCRFCD, and North Las Vegas Airport. Performed most hydraulic analysis and design forthe dotontion boain and the rattonsivc inlet and outlet otorm drain

C:\WlNUOWS\TEMP\Sorensen_255.doc Standard Form 255 (REV 11-92)

June 9,1999

Mr. David Basinger (WTR-7)Water DivisionU.S. EPA Region IX75 Hawthorne StreetSan Francisco, California 94105

Re: Sunrise Mountain Landfill CWA 309-9-99-14Order for Compliance, Item #19 and #20

Dear Mr. Basinger:

Enclosed please find two (2) copies each of HLA's Report for the above referenced tasksfor the Sunrise Landfill. HLA prepared the reports as contractor to Republic DUMPCo,Republic Industries, and Republic Silver State Disposal Inc. The reports document thecondition of the Sunrise Landfill in fulfillment of Task #19, and recommend a plan forinterim repairs in fulfillment of task #20.

The reports are each signed and stamped by a Professional Engineer. I certify underpenalty of law that this document and all attachments were prepared under my directionor supervision in accordance with a system designed to assure that qualified personnelproperly gather and evaluate the information submitted. Based on my inquiry of theperson or persons who manage the system, or those persons directly responsible forgathering the information, I certify that the information submitted is, to the best of myknowledge and belief, true, accurate, and complete. I am aware that there are significantpenalties for submitting false information, including the possibility of fine andimprisonment for knowing violations.

If you have any questions regarding this submittal, please contact Mr. John Schlegel ofthe Clark County Comprehensive Planning at 702-455-3113 or me at 702-734-5400.

truly,

AlanJ. Gjjd/y /Vice President /Certified Environmental Manager

AG/im

cc: Mr. Mike Dwyer - BLMMs. Susanna Trujillo - EPAMr. John Schlegel - Clark County Comp. PlanningMr. Greg Walch, Esq.

770 East Sahara Avenue • P.O. Box 98508 • Us Vegas, Nevada 89193-8508 'Telephone (702) 735-5151 • Fax (702) 735-1986

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