sunrise mountain landfill 1999 administrative record ... · 100-year storm intensity is 1 7...

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SFUND RECORDS CTR

2095746

Sunrise Mountain Landfill Final Cover Evaluation

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prepared for the Bureau ot Land .Management

under contract with D>nan:iac Corp (TS-\ 97-003j

prepared bv Stephen F Dvvver

November 13, 199'

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PVNAMAC CORPORATION Environmentai Services

Bureau 0^^7 30

November 24.1997 UOM ^ ^

tAS;^rOF?^ce Mr MikeMwan OlSTP^ ,4eva<i* Bureau of Land Management \_aS V ^ ' Las Vegas Ehstnct Ofl5ce 4765 West Vegas Dnve Las Vegas. Nevada 89108

Dear Mr Moran.

Enclosed are inserts to the document entitled Sunnse Mountam Landfill Final Cover Evaluation The mserts contam the changes to the document as requested by the bureau Mr Dwyer has also prepared an Executive Summary of his findmgs which is as follows

"This evaluation ofthe Sunnse Mountain Landfill identified several out of compliance issues with regard to the final cover The cover does not meet requirements of 40 CFR 258 lis thickness does not meet the mirumum requirement and its hydraulic conductivity exceeds the maximum allowable limit A safety violation was also identified with regard to gas emissions Methane gas escaping in one area wasfouruito exceed the lower explosive limit

The excessive cracking found throughout the final cover and the continued erosion warrant a formal and regular maintenance schedule The existing cover does not meet applicable regulations A large amount of gas is escaping the landfill with no controls This is a problem that should be addressed immediately The landfill needs to be closed wtth a cover that meets these regulations Methane gas emission momtonng was agreed to be conducted in the final closure plan but IS not currently being performed Due to the out of compliance issues found and the probabihty that large amounts of infiltration are being generated, it is recommended that groundwater momtonng be installed to monitor possible contaminate migration through leachate escaping the landfill Erosion due to surface runoff is not adequately controlled with the existing drainage system It is recommended this be redesigned to minimize surface erosion The findings of this effort are significant and found upon only a cursory review ofthe landfill condition Such findings warrant further comprehensive analysis ofthe overall condition ofthe landfill "

Should you have any additional questions or comments, please feel free to call me at (301)417-6063

Respectfully.

Phil Werner. Sr Geologist

cc S Skmner .NVSO B Lewis. NARSC

enclosures A i ^ ^ / > . f r ^ J ^ A/o.^ ec'/^ '^s ro A T T ? ^ ^ ' ^ ^ - ^ ' ^ < ,

The Dynamac Building, 2275 Research Boulevard, Rockville, MD 20850-3268 Telep..one (301) 417-9800, Fax (301) 417-9801

Sunnse Mountain Landfill Final Cover Evaluation

Table of Contents

1 0 Consultant Responsibilities

2 0 Sunnse Mountain Landfill Closure DocumentaUon / Quality Control

3 0 Landfill Cover Requirements

4 0 Site Visit to the Sunnse Mountain Landfill

4 1 Trench 1

4 2 Trench 2

4 3 Trench 3

4 4 Trench 4

5 0 Summary of Observauons

5 1 Cracking

5 2 Cover Requirements

5 3 Runoff Concems

5 4 Stability Concems

5 5 Gas Emission Concems

6 0 Summary of Closure Compliance Issues

7 0 Recommendations for BLM Consideration

7 1 Gas Emissions

7 2 Maintenance of Existing Cap

7 3 Existing Cover

7 4 Final Cover InstallaUon

7 5 Groundwater Momtonng

7 6 Rework of the Surface Drainage System

7 7 Complete Analysis of Entire Site

8 0 References

Attachment A - Clark County Health Distnct, Quality Control Documentation

Attachment B - Notes and Observations by Brent Lewis, BLM

Attachment C - Excavation Procedure

Attachment D - Qualifications of Stephen F Dwyer

Sunnse Mounuin Landfill Final Cover Evaluation

Attachment E - Memos and Fact Sheet RelaUng to Municipal Solid Waste Emission

Guidelmes

Attachment F - Landfill Cover Soil Quality Assurance

Attachment G- Site Map

Sunnse Mountain Landfill Final Cover Evaluauon

1 0 Consultant Responsibilities

As requested by the Bureau of Land Management (BLM) and contracted by Dynamac Corporation (Techmcal Services Agreement 97-003), an evaluaUon of the closure of Sunnse Mountain Landfill was performed The objechve was to compare the existing condition of the landfill final cover to the approved closure design Any issues found not to be in compliance or quesUonable were identified The work statement specifically requested is as follows

1 Assess the as-built cap against the approved design in the followmg areas a Thickness of the cap The BLM provided access to specified areas and

provided an operator and backhoe for excavation of cover matenal b Permeability of the cap Recommend procedures for determimng whether the

cover currently achieves design standard Evaluate any data collected to determine the permeability of the cover This may require recommendations and oversight of the installation of field instmmentation

2 Determine the depth and cause of crackmg which is cunently occumng in the cap BLM provided access to specified areas and a backhoe with an operator for excavauon of cover matenal A procedure developed by the BLM was used for excavations

3 Surface erosion is a major problem at the landfill The BLM would like to understand a Does the as-built design match the approved closure design*^ Does the

approved design follow industry standards'' BLM will supply survey results of the as-built slopes for this companson

b Provide recommendauons capable of reducing the amount of surface erosion 4 Evaluate the current surface water diversion design against Subtitle-D standards

or industry practices Provide recommendations for reducing the amount of erosion and channel destruction

2 0 Sunnse Mountam Landfill Closure Documentation / Quality Control

All applicable and available documentation of the Sunnse Mountain Landfill provided by the BLM was reviewed The following documentation was reviewed

Table 2.0-1. Related Documents Reviewed

Document Prepared by Prepared for Date Sunnse Mountain Landfill Expansion

Regulatory Compliance Audit Report, Sunnse Mountain Landfill,

EMCON Associates DUMPCO, Inc December 1986

Advanced Sciences, US Dept of Intenor Novembers, 1991 Inc

Las Vegas, NV

Sunnse Mountain Landfill Plans for Final Landfill Closure

Sunrise Mountain Landfill Closure Plan

Sunnse Mountain landfill Constmction Quality Assurance Plan

Sunnse Mountain landfill Surface Water Management Plan

Memo - Sunnse Landfill and Subpart Cc

Final Site Evaluation Project Plan, Sunnse Mountain Landfill, Clark County, NV

Memo - Municipal Solid Waste Landfills

A summary of th< work is outlined 1 these findings are accurate

1 Sunnse Moun • groundwal • most rec hi • groundwa


Harding Lawson Associates

Harding T iwson Associates

Harding Lawson Associates

Harding T wson Associates

Clark County Health District

CC Johnson & Malhotra

Clark County Health Distnct

DUMPCO, Inc Apnl 12, 1994



DUMPCO, Inc May 9, 1994

Clark County Health Febmary 13, 1997 DisU-ict, Supervisor

US Dept of Intenor, Febmary 20, 1997 BLM

Distnbution (not June 11, 1997 included)

i findings in these documents found to be relevant to this scope of jelow There are some inconsistencies between documents Note that of the agency prepanng the documents and may or may not be

tain Landfill Expansion (EMCON for DUMPCO, 12/86) .er flow IS from NE to SE irge occurs at westem edge of basin due to sand/gravel deposits .er depth beneath landfill is about 200-feet

5


clay deposits were found m soil bonngs perfonned groundwater movement within the clay deposits is approximately I to 10 feet per year groundwater quality is generally poor with an average total dissolved solids of about 3500 g/1 claimed a monitormg program would be mstalled for leachate site IS 720 acres leased by BLM to Clark County under contract to DUMPCO iniUal lease 320 acres dated 5-21-82 for 20 years second lease 400 acres dated until 5-20-88, a 3-year lease this document requests an extension of these leases site average annual precipitauon is about 4 35 inches/year 100-year storm intensity is 1 7 inches/hour landfill was to have a one-foot intermediate cap with a 4-foot final cover a leachate collection system was to be provided at the toe of the landfill the site's soil has a gypsum content between 20 and 40% site soil analysis yielded the followmg • Plasticity Index (PI) 10 to 15 • clay sand maximum dry density (MDD) = 130pcf, optimum moismre

content (WopO of 8%, saturated hydraulic conductivity (ksat) at 90% compaction per ASTM 698 of 2 x 10" cm/sec

• silty sand MDD = 124 pcf, Wop, = 9%, ksat = 1 x 10" cm/sec • silty sand with gypsum MDD = 121 pcf, Wop, = 12%, ksa, = 8 x 10^

cm/sec

Sunnse Mountain Landfill Closure Plan (Harding/Lawson for DUMPCO, 4/94) • over the past 2 years, waste accepted was about 3400 tons per day • waste consist of municipal waste, asbestos, sanitary sludge, constmction

debns, medical waste, septage waste treated soil, and hydrocarbon contarmnated soil

• refuse capacity is 60,936,000 CY • service life is 31 years • landfill stopped accepUng waste pnor to 10-9-93 • SubUtle D (40CFR258) went into effect 10-9-91 • landfill closure to meet 40CFR258 60(a) • parts of landfill that did not accept waste after 10-9-91 are not part of the

closure plan • existing intermediate cover pnor to final cover is 12-inches of soil • the intermediate cover may be regraded to a rmnimum depth of 6-inches to

prepare subgrade for installaUon of the final cover • final cover is to have a bamer layer 18-inches thick with soil that yields a

maximum ksat of 1 x 10" cm/sec with an top erosion layer to protect against erosion consisting of 6-inches of soil, the soil shall contain soil with gravel (15%) and silt (15 to 20%)


• final cover to be placed only over area of landfill that accepted waste between 10-9-91 and 10-9-93 which is about 180 acres

• other areas of landfill not to receive final cover were covered with a cap based on Clark County Health Distnct specificahons dated September 1990

• 100-year storm event is I = 3 15" (6-hour), 25-year storm is 1= 2 53" (6-hour) • permeability measurements of fill @ 90% of MDD are ksat = 3 x 10 ^ cm/sec

to 5 X 10" cm/sec • subsurface water flow is west at 1 to 10 feet/year with total dissolved solids of

3500 mg/l • culverts were designed for 25-year storm • because no waste was accepted after 10-9-93, momtonng is not required • due to agreement with Clark County, methane gas momtonng will be

performed • 2 existing wells are not usable for groundwater momtonng first one because

of the way it was constmcted, the second because it is dry

3 Regulatory Compliance Audit Report, Sunnse Mountain Landfill, Las Vegas, NV (Advanced Sciences for BLM, 11/91) • potenUal non-comphance issues noted

a lack of groundwater momtonng program b lack of financial assurance mechanism c lack of methane gas momtonng

4 Surmse Mountain Landfill Constmction Quality Assurance Plan (Harding/Lawson for DUMPCO, 4/94) • soil used for cover to h& passed/rejected based on moisture content (ASTM

D2216), PSD (ASTM D1140, D422), Atterberg Limits (ASTM D4318), Laboratory Compaction (ASTM D1557), Laboratory Hydraulic Conductivity (ASTM D5084)

• the plan discusses frequency of test and types to be performed but makes no mention of acceptance cntena.

5 Sunnse Mountain Landfill Plans for Final Landfill Closure (Harding/Lawson for DUMPCO, 4/94) • area mvesugated under this work scope is on area designated as that which

received mumcipal solid waste • area investigated under this work scope is definitely part of the areas

designated to receive a final cover per drawmgs

6 Sunnse Mountain Landfill Surface Water Management Plan (Harding/Lawson for DUMPCO, 5/94) • an off site storm water diversion system was built to minimize surface erosion • the system was designed for a 25-year, 6-hour storm • mnoff calculations done with HEC I computer program


• soils classified as hydrologic soil classificaUon ' C or 'D' • rainfall data obtamed from Clark County Regional Flood Control Distnct

manual (1990), 25-yr, 6-hr storm event mtensity is 2 53 inches • analysis performed per Clark County Regional Flood Control Distnct manual

Mr Victor Skaar of the Clark County Health Distnct was asked to supply any quality control information gathered dunng the actual installation of the final closure of the landfill A verbal request to Mr Skaar was made on October 6, 1997 On October 10, 1997, Mr Skaar informed me that an official request had to be processed through appropnate channels to receive this information (specifically a wntten letter to David Rowles, Director of Admmistrauon, Clark County Health Distnct requesting the mformaaon) This wntten request was mailed to Clark County Health Distnct on October 13, 1997

The informauon was received November 3, 1997 It consists of a letter (stamped by a Professional Engineer) from Harding Lawson to DUMPCO dated 3-22-95 venfying the landfill was closed per the Sunnse Mountain Landfill Closure Plan dated 4-14-97, a Certificate of Comphance (stamped by a Professional Engineer) from Vector Engmeermg dated 3-28-95 staUng the earthen matenal used to install the cover was placed as specified, a letter from DUMPCO to Clark County Health Distnct dated 3-3-95 notifying the County that Sunnse Mountain Landfill is fully closed as of 3-1-95, and a copy of the Sunnse Mountain Landfill Constmction Quality Assurance Plan dated 4-14-94 Refer to Attachment A for copies of this informauon

There was no documentaUon that contained any quantitative data showing that the closure does in fact meet the intent of 40CFR258 This quanUtaUve data would mclude such things as results of tests performed dunng the cover installaUon on matenals installed, and on the installaUon of these matenals The Sunnse Mountain Landfill ConstmcUon Quality Assurance Plan discusses tests to be performed and their frequency, but makes no mention of acceptance cntena

3 0 LandfiU Cover Requirements

On October 9, 1991, the US Environmentai Protection Agency (EPA) promulgated revisions to the Cntena for the Classification of Solid Waste Disposal Facilities [40CFR257] and developed revised imnimum federal cntena for municipal solid waste landfills (MSWLs) [40CFR258] These regulations were promulgated pursuant to Section 4010 of the Resource ConservaUon and Recovery Act (RCRA) (added with passage of the Hazardous zind Solid Waste Amendments of 1984), which directed EPA to revise the RCRA cntena for facilities that receive hazardous waste generated by households or small quanuty industnal generators The MSWL regulations [40CFR258] were also promulgated pursuant to Section 405 of the Clean Water Act, which required EPA to establish standards for sewer sludge that is codisposed with municipal waste


These regulations became effecUve October 3, 1993 MSWLs that stopped receiving waste pnor to that are exempt from these requuements, except for the final cover requirement States are responsible for implementing and enforcing the new MSWL cntena. They are required to incorporate the new federal standards into existing waste permittmg programs

The owner/operator of the landfill must install a final cover system designed to effectively isolate the waste from the surrounding environment by rmmmizmg the infiltrauon and erosion Specifically the cover system must (1) have a permeability or saturated hydraulic conducuvity less than or equal to that of the bottom liner or natural subsoils present, or no greater than 1 x 10^ cm/sec, whichever is less [40CFR258 60(a)(1)], (2) numnuze infilttauon through the closed MSWL by the use of an infiltraUon layer contairung a mimmum 18-inches of earthen matenal [40CFR258 60(a)(2), and (3) minimize erosion of the final cover by the use of an erosion layer contaimng a rmmmum 6-inches of earthen matenal that is capable of sustaimng native plant growth [40CFR258 60(a)(3)]

According to the Sunnse Mountain Landfill Closure Plan (1) the landfill stopped accepting waste pnor to October 9, 1993 to avoid having to completely comply with the new federal regulations for mumcipal landfills (40CFR258), (2) the areas of the landfill accepUng waste pnor to October 9, 1991 are not subject to the new Resource Conservation and Recovery Act (RCRA) Subtitle D regulauons but govemed by Clark County Health Distnct specifications dated September 1990, (3) the areas of the landfill that accepted waste between October 9,1991 and October 9, 1993 are the only areas requinng a final landfill cover that meets the RCRA Subtitle D requirements The author of this report does not necessanly agree with these last two statements Refer to section 6 0 for a bnef summary of the reasomng for disagreement with these statements It is recommended that apphcable regulators or goveming authonties make an informed decision whether these statements are vahd

4 0 Site Visit to the Sunnse Mountain Landfill

A site visit to the Sunnse Mountain Landfill was performed on October 2, 1997 The attendees mcluded Brent Lewis, BLM - Denver, Mike Moran, BLM - Las Vegas, Victor Skaar, Clark County Health Distnct, and Steve Dwyer, consultant Also in attendance were an equipment operator and ranger employed by BLM

The purpose of the visit was to assess the installed cover and determine whether it met the approved closure plan A general tour of the enture landfill was conducted by Mike Moran Excavations were performed on the upper portion of the landfill where municipal waste is buned according to the Sunnse Mountain Landfill Plans for Final Landfill Closure (sheet 3 of 16) A procedure developed by BLM was used dunng excavauon activities (see Attachment C)

Sunnse Mountain Landfill Fmal Cover Evaluation

Four pits were dug Refer to Attachment G for a site map locating these pits Their locations determmed with Global Positioning System (GPS) are as follows

Trench 1 36° 08' 46 6" 114° 59' 45 9"

Trench 2 36° 08' 316" 114° 59' 46 2"

Trench 3 36° 08' 25 1" 114° 59' 43 5"

Trench 4 36° 08' 25 0" 114° 59' 45 1"

4 1 Trench 1 was located on the northem third of the uppermost tier It was dug where a crack exists This crack was partially visible intermittently in excess of 100-feet (Picture 4 1-1)

k yXA^AA:: . ' Picture 4 1-1 Cracks Intermittently Visible (10-2-97)

Some maintenance had been attempted on the cover to repair the cracking prior to our arrival It appeared that a grader was used [o regrade the surface of the co\er to fill m the cracks Unfortunately, the cause of the cracking has not gone awa\


Most of the cracking in this area mns north-south The trench was excavated until waste was discovered Trash was encountered at a depth of 21-inches The top 18 or 19-inches appeared to be compacted soil The crack ran completely through this cover Just below this compacted soil was a thin 2-inch thick layer of sand (reddish brown color) that was umformly moist Immediately below the sand was soil mixed with waste The waste was a black color Excavation was continued to a depth of about 2 5-feet where pure waste was encountered Very strong odors began emanating from the hole as soon as this trash was exposed The cover in this area seemed to be retarding the vertical escape of gas in any large quantity No attempt was made to identify the specifics of the waste The crack that protruded mto the waste was partially filled with a fine sandy loam that was moist to the touch It was an obvious point of infiltration

The cover appeared to be about 18 or 19-inches thick in this area It was compacted in multiple hfts A couple of chunks of compacted soil were removed during excavation that indicated a smooth rolled compactor was probably used to compact the lifts of soil composing the cover There was an apparent smooth interface joint left between the hfts (Picture 4 1-2)

i

PICTURE 4 1-2 Smooth Surface Reveals Interface Joint Between Lifts (10-2-97)

This goes against good construction practices used in constructing barrier layers Generally the preceding lift should be scarified to a depth of an inch or two to eliminate any interface joint Interface joints can serve to allow infiltration bv providing a path of least resistance for the water to follow to the underlying waste (Figure 4 I-lj Gases can follow the same route in reverse


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Figure 4 1-1 Percolation Through Cracking in Lifts with Interface Joints

3

The soil appears to have a significant amount of calcium carbonate and/or gypsum in It The "cementing" effect this has on the soil is probably the reason for the exaggerated crackmg

4 2 Trench 2 was excavated on the lower portion of the upper tier's northem section This trench was also excavated where a crack exists This trench was excavated to a depth of about 18-inches where waste was discovered The crack continued through to the underlying waste The crack was filled with a fine sandy loam that was moist to the touch, again an obvious infiltration point The soil appeared to have been placed in two hfts The bottom hft was 9-inches of compacted soil while the upper 9-inch lift was observed to have minimal compaction - not sufficient for a bamer layer's purpose The soil excavated from Trench 2 contained large stones - greater than 6-inches in diameter (Picmre 4 2-1) These large stones cut down on the effective depth of the bamer layer by the size of their diameter


Jr%f^m^^ PICTURE 4 2-1 Large Stones Found in Barrier Layer, Trench 2 (10-2-97)

Surface cracking m this area is random mnnmg in multiple directions The cracking is more extensive than the area Trench 1 was located in The area has been regraded in an effort to fill the cracking, but the cracks contmue to be exposed

3

4 3 Trench 3 was excavated on the lower portion of the upper tier This area was chosen because it had some vegetation growth on it The vegetation appeared to be tamansk This growth was evidence of moisture content in the soil probably the result of ponding in a depressed area (approximately 500 square feet) caused by differential settlement It was one of the few spots with anything growing on it (Picture 4 3-1)

The excavated soil from the depression was moist It was consistently moist down to the waste The material appeared to be a sandy loam with rounded gravel in It There was no surface cracking in this area The material excavated was loosely placed There appeared to be no compaction Roots were visible to an 18-inch depth The loose soil was excavated to a depth of about 24-inches where waste was discovered The waste was black in color


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PICTURE 4.3-1. Surface Depression with Vegetation, Trench 3 (10-2-97)

4 4 Trench 4 was excavated on the lower portion of the upper tier about 100-feet west of Trench 3 This area was chosen because of the surface staining due to gas emissions found in the general area (Picture 4 4-1)

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PICTURE 4 4-1 Surface Staining Due to Gas Emissions (10-2-97)

There was no apparent surface cracking in this general area In fact, the southem third of the lower portion of the upper tier does not appear to have surface cracking Excavation discovered waste immediately below the surface (Picture 4 2-21


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PICTURE 4 4-2 Waste (Black Matenal) Just Below Surface - No Cover (10-2-97)

The waste was black with some lightly colored gray soils There seemed to be a petroleum-based aroma emanaUng from the waste

A photo-ionizing detector (PED) and an explosimeter were used during excavation to monitor escaping gas levels During this site visit the wind was strong (generally greater than 20 mph) Despite these strong winds aJanrung levels ot vapors were detected Refer to Attachment B in notes by Brent Lewis, BLM for PID readings taken during excavation of the trenches

5 0 Summary of Observations

5 1 Cracking The surface cracking found throughout the areas of the landfill wheie some type of a final cover was installed appears to be predominantly caused due to diffeiential settlement The longitudinal cracbng photographed by BLM along the top of the westem slopes of the municipal waste area had been regraded after the date of the BLM photo (Picture 5 I-l) and were not totally visible upon our site visit dated October 2, 1997 This cracking too appears to be caused from tensile stresses in the soil caused by differential settlement There also appears to be some minor desiccation cracking Gas pressures may also be a contributing factor


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PICTURE 5 1-1 Longitudinal Crackmg (9-4-97)

The cracking found in the areas of Trenches 1 and 2 extends completely through the cover to the underlying waste This in effect has defeated the purpose of the cover as being an impermeable layer The moisture found in the soil in the cracks and that under the cover is evidence that water is percolating through these points into the underlying waste

There was little to no cracking found m the areas of Trenches 3 and 4 The primary reason for the absence of cracking is that there appears to be no final cover in these areas Trench 3 appears to have soil over the waste that was loosely placed This is probably the remains of an interim cover or soil from subgrade preparation for a final cover The area around Trench 4 only has an inch or so of soil covering the waste There is no interim cover nor final cover in this area The extensive surface staimng is evidence that gas emissions are escaping vertically throughout this area In the areas where Trenches 1 and 2 were located, there is little surface staimng The soil excavated has a very strong odor to it, however

The major mechanisms of refuse settlement mclude (a) the mechanical consolidating or void ratio reduction by distortions, bending, cmshing, and material reorientation, (b) raveling or the movement of fines into large voids, (cj physical-chemica] changes from corrosion, oxidation and combustion, (d) bio-


chemical decomjwsiuon fi-om fermentauon and decay The refuse will settle from both its own weight and that of the fmal cover

The factors that influence the magnitude of settlement are almost unlimited but mclude • refuse type or charactenzaUon (e g, constmcUon debns vs mumcipal waste) • refiise density or void ratto • content of decomposing matenals • waste fill depths • weight of final cover • landfill operaUonal history • leachate levels • environmentai factors such as moisture content, temperature, and gases

present • water table locauon

The EPA recommends delaying the installation of the final cover unUl after the sigmficant amounts of differenttal settlement have taken place (EPA 1990) The clay bamer layer in a final cover will conUnue to crack as long as significant amounts of differential settlement are sull occumng The EPA recommends placing an intenm cover over the waste dunng this time penod The delay of the final cover installation may not be an option, however

5 2 Cover requirements Soil samples were taken from the soil excavated from Trenches 1 and 2 that composed what is claimed to be a final cover These samples were analyzed to see whether the soil matenal used was suitable to serve as a final cover The tests performed and results are summanzed in Table 5 2-1

Table 5.2-1 Soil Tests Performed

Test Particle Size Distnbution

Gravel (>4 76mm) Fines (<0 075mm)

Hydrometer Test Clay (<0 002 mm)

Standard Proctor Test

Atterberg Limits Liquid Lirmt

ASTM Standard C136/D1140

D422

D698

D4318

Trench 1 Sample see Attachment F

18% 35 8%

see Attachment F 2%

see Attachment F

39%

Trench2 Sample see Attachment F

33 3% 33 8%

-

see Attachment F

23%

17


Plastic Limit Plasticity Index

Hydraulic Conductivity

Kioosc

K9o%

^ 9 5 %

In-situ Hydrauhc Conductivity (Kciod)

Clod Density

D5084

D5084 (modified)

17% 21%

8 46 X 10' cm/sec 2 63 x 10" cm/sec <10" cm/sec

<10^ cm/sec

127 5 Ib/ft

21% 2%

-1 X IO"'cm/sec 9 1x10^ cm/sec

-

no clods

The particle size distnbution (PSD) found is only an apparent distnbution Standard test methods were followed to determine this distnbution These methods do not take into account the affect of salts (m this case calcium carbonate and gypsum) The salts bond with silts and clays which affects the PSD outcome The soil should be pretreated pnor to determimng the PSD by washing it with appropnate acids (Francis, Aguilar 1995) The acid washing was not performed

The PSD revealed a high fines content (particles retained on the no 200 sieve) A hydrometer test was then conducted on the matenal excavated from Trench 1 This test revealed that only about 2% of the fines retained were actually mineralogical clay There was a large volume of gypsum present The gypsum lead to a cementing of the soil giving it what appears to be a higher plasticity mdex The matenal excavated from Trench 2 appeared to have more calcium carbonate than gypsum The Trench 2 matenal had a very low plasticity index confirming the lack of clay in the sample

A standard proctor curve was established for both sample matenals There was no defimtive evidence found that indicated the compaction level the soil was to be compacted to dunng installation of the final cover Compaction levels of 90% were referred to m some of the reviewed documentation (Sunnse Mountain Landfill Expansion and Sunnse Mountain Landfill Closure Plan) from laboratory testing on the matenals pnor to the landfill closure This is a common standard and consequently was assumed to be the number they were "shooting" for Based on the standard proctor curve obtained for each respective sample, hydraulic conductivity tests were mn There were three senes of tests mn on the matenal from Trench 1 The first was of the loose matenal obtained This matenal was compacted to 90% where the hydraulic conductivity was detenmned to be 8 48 x 10 cm/sec It was obvious the gravel content was too high and clay content too low Two chunks of compacted soil were also obtained from Trench 1 The matenal in the chunks is the matenal tested for all of the results shown in Table

18

Sunnse Mountam Landfill Final Cover Evaluation

5 2-1 except Kioose One of the chunks was broken down and molded mto a cylinder and compacted to 90% where the hydraulic conductivity was deternuned to be 2 63 X 10" cm/sec The gravel content was lower in this sample and the gypsum content was very high A sample was then compacted to 95% where the hydraulic conductivity was found to be lower than the 1 x 10^ cm/sec requirement The high gypsum content is believed to be the reason for the lower hydraulic conductivity The weak cementing effect that took place however leads to the exaggerated cracking revealed on the landfill due to tensile stiesses from differential settlement

The second chunk of compacted soil ft-om Trench 1 was preserved and cut to fit the mold used for hydraulic conductivity testing Its hydraulic conductivity was found to also be less than the 1 x 10^ cm/sec The high gypsum content is believed to agam be the reason for the low permeability

The matenal excavated from Trench 2 was tested All matenal taken from this trench was obtamed loose Very little clodding was observed in Trench 2 dunng excavation Samples compacted to 90% and to 95% were tested where the hydraulic conductivity's were both found to be about 1 x 10' cm/sec - two orders of magmtude above the mimmum requirement The cementing effect observed from the matenal from Trench 1 was not so evident in this matenal

Table 5 2-3 summanzes general soil charactenstics that should be adhered to when constmcting a bamer layer to achieve a low permeable bamer layer (EPA 1991) Generally, the higher the clay content in the soil, the lower the hydraulic conductivity and thus the more impermeable the layer is A recommended minimum of fines is 20% Fines are defined as the percentage on a dry-weight basis, of matenal passing the No 200 sieve which has opemngs of 0 075 mm The key is that these fines be mineralogical clay In the case of the soil used in the cover on the Sunnse Mountain Landfill excavated from Trenches 1 and 2, the fines have a high calcium carbonate and/or gypsum content with an inadequate amount of clay The soil used should have a plasticity index of at least 10% In some cases a slightly lower index is allowable In general, soils with plasticity indices less than about 10% have very little clay and usually will not produce the necessary low hydraulic conductivity required

The percentage of gravel (defined as matenal retained on the No 4 sieve which has openmgs of 4 76 mm) must not be excessive A maximum amount of 10% gravel IS suggested as a conservative figure In some cases more gravel is acceptable Gravel is only deletenous if the pores between gravel particles are not filled with clayey soil and the gravel forms a pathway through the bamer layer An excessive amount of gravel was found in the soil analyzed Trenches 1, 2, and 3 all were found to have excessive amounts of gravel in the cover material There was no cover in Trench 4 This large amount of gravel was found to be clotting in areas and thus making the bamer layer very permeable No stones or rocks larger

19


than 2-inches should be present in the cover soil The large stones (Picture 4 2-1) found in the soil excavated from the trenches effectively reduce the depth of the cover in those areas

The key to constmcting the bamer layer in the cover is to produce an impermeable layer to prevent infiltration and thus percolation into the underlying waste 40CFR258 60(a) defines an effective bamer layer for MSWL as possessing a saturated hydraulic conductivity of no greater than 1 x 10 cm/sec The soil used for the constinction of a cover in Trenches 1 and 2 does not meet this requirement

Table 5.2-3 - Bamer Soil Charactenstics (EPA 1991)

Quahty Item Percent Fines Percent Gravel Water Content PI Max Clod/Stone Size Saturated Hydrauhc Conductivity

Bamer Soil 20 % nummum 10% maximum Wet of optimum 10 to 35 None larger than 2" I X 10' cm/sec, max

Another concem in the constmction of this landfill cover was also observed The lifts in Trench 1 appeared to be compacted with a smooth rolled compactor The bottom lift was not scanfied pnor to the installation of the upper lift This created an interface joint between lifts which can serve as both a comdor for the percolation of water or the migration of gas It is good practice to eliminate the possibility of an interface joint in order to get the bamer layer to act as an 18-inch layer rather than three six-mch layers

5 3 Runoff concems Erosion of the final cover can be controlled by such things as vegetation, drainage terraces, and armored drop stmctures The surface mnoff system must be capable of conveying mnoff down the side slopes without creating erosion nils and gullies The erosion contiol features should be designed so that long-term maintenance is minimized Diversion stmctures may also be needed to prevent water from mnning onto the landfill cover and causing erosion and increased infiltration After drainage is directed off the cover, penmeter drainage features such as ditches, gabions, or storm sewers are required to carry the water away from the toe of the landfill

The Sunnse Mountain Landfill appears to have had a drainage plan implemented The hundreds of lineal feet of cormgated metal collection pipes appears to have been an expensive undertaking It does not appear to be working very effectively, however (Picture 5 3-1) The erosion protection installed does not appear to be

20


mitigating the erosion that is taking place (Picture 5 3-2) If left as is, maintenance of the site to repair damage from erosion will be continual and expensive Vegetation has traditionally been one of the primary defenses against erosion At this site, this does not appear to be feasible The severe and climate and lack of nutnents m the soil will make vegetation impractical An armored surface on the other hand could be very effective The soil in the area has large amounts of gravel in it The fill to be used for the final cover could be sieved, with the gravel being removed and spread thinly (about an inch or two thick) on the surface (including slopes) to help reduce erosion effects The culverts that exist are not adequately controlling mnoff during high intensity storms The surface mnoff appears to be directed along the penmeter of the culverts creating deep cutting gullies adjacent to and below them that is exposing waste (Picture 5 3-3)

3

!.«.

Picture 5 3-1 Runoff Collection System after High Intensity Rainfall Event (6-7-95)

21


^ s ^ ^ ^ i

Picture 5.3-2. Side Slope Erosion (6-7-95)

3

Picture 5.3-3 Waste Exposed Under Culvert (9-20-95)

A senes of ditches lined with a geomembrane and riprap similar to that installed along the southeastem side of the landfill might be a better choice Another concem is with the avoidance of mn-on at the northem side of the landfill (mumcipal waste cells) It is questionable whether the ditches created are adequately directing the water around the eastem side of the landfill as designed It appears there may be some ponding on the nonhern slope of the landfill creating an infiltration zone

Potential problems conceming the lined ditch along the southeastem side of this waste ceil exist due to the fact that it was constmcted over waste (Picmre 5 3-4)


Differential settlement under a section of the ditch could cause depressions leading to ponding and thus mcreased infiltration The depressions could create excessive tensile stresses that could cause tearing of the ditch limng (geomembrane) also increasing infiltration The flow could potentially be redirected away from the lined areas due to differential settlement effects on the topography along the ditch

Picture 5.3-4 Waste Under Lined Trench (3-17-94)

5 4 Stability Concems The fmal cover over the landfill must remain stable through the design life and beyond All portions of the landfill system must be stable including the natural foundation materials below and beyond the landfill, the refuse matenal and the cover material Slope stability failures can be catastrophic both economically and environmentally The problem with stabihty is that an accurate analysis is difficult to perform The landfill materials are generally highly variable and also vary with time In addition, quantification of the waste materials is difficult There are a number of circumstances that can affect the stability of the landfill slopes Gas uplift forces can reduce stability, leachate trapped under the low-permeability bamer layer of the final cover can create a hydrostatic pressure head which can reduce stability, and tension cracks can allow surface mnoff to infiltrate the soil in sufficient quantities where the hydrostatic pressures build up leading to slope instability are a few such circumstances The obvious instability issues sucn as steep slopes, inadequate materials, and low friction interfaces such as can occur with geomembranes are the more common reasons


At present, there does not appear to be a major slope stability problem with the landfill However, some of the potential problems listed above could evenmally lead to senous stability problems There are some areas that are expenencing isolated stabihty problems that should be immediately corrected so they don't lead to bigger problems Picture 5 4-1 shows an isolated slope stability problem located along the toe of the southwestem slope of the mumcipal waste cells adjacent to a mnoff collection culvert

I f . ' - ' • .

. ^ . 1 - ^ -

/ "

W m i ^ ^ ^ ' A ' * r . - ' A - ,

' - '% K'Wim^^'Jj^' - ^ yiAA.~> y-1 A •^Mmf-rm^^

/

PICTURE 5.4-1 Isolated Slope Stabihty Problem (9-4-97)

U

This particular case appears to be caused from inadequate contiol of surface mnoff The culverts are creating deep gully erosion problems by directing mnoff along the exterior of the culvert and undercuttmg the soil along the toe of the landfill in this area The tension cracking near the surface should be contiolled to mitigate any potential for senous stabihty problems Leachate should be mimmized as well for the same reason

5 5 Gas emission concems Degradation of solid organic waste matenals in a landfill generates gases The composition of MSWL gas generally is about 50% methane, 40% carbon dioxide, and 10% other gases including nitrogen products (EPA 1991) The carbon dioxide IS heavier than air and will move downward The methane, however, is lighter than air and will move upward Gas migrates from landfills through two mechanisms, convection and diffusion (EPA 1991) Convection is transpon induced by pressure gradients formed by gas production in layers surrounded by low hydraulic conductivity or saturated layers Convection also results from buoyancy forces since methane is hghter than air Diffusion is the transport of materials induced by concentration gradients Anaerobic decomposition produces a gas mixture with concentiations of methane and carbon dioxide that are much greater than those found m the surrounding an Therefore, molecules of methane

24


and carbon dioxide will diffuse from the landfill gas to the air in accordance with Pick's law Diffiision plays a much smaller role m gas migration than convection

Gas migration rates are affected by the type and age of refuse matenal, the final cover design, refuse temperature and moisture content Vertical or lateral migration paths for gas movement are influenced by the fmal cover design and the presence of migration comdors and/or bamers Migration comdors include sand and gravel lenses, void spaces, cracks, fissures, utility conduits, dram culverts, and buned lines Bamers to gas nugration include clay deposits and high and perched water tables Saturated or frozen surface layers promote lateral migration of landfUl gases

The potential impacts of gas generation are as follows • Explosion hazard Methane gas can migrate laterally and vertically and collect

in adjacent stmctures, creating a potential explosion hazard • Vegetation disttess Landfill gases can disttess the vegetation on a landfill

cover • Odor Odor control becomes a design parameter if the landfill is located

adjacent to existing or potential developments • Physical disruption of cover system Landfill gases can also cause cracking of

the bamer layer resulting in increased permeability • TOXIC gases Gases produced by landfills can be toxic or may not comply with

regulatory requirements

Refer to Attachment B for levels of gases recorded dunng the October 2 site visit The levels in some areas were alarmingly high One reading exceeded 25% of the lower explosive limit [40CFR258 23(a)] Widespread surface staimng was observed, particularly in areas where there was little or no covenng above waste There is no mechanism in place to conttol the migration of gases at the landfill site at this time

6 0 Summary of Closure Compliance Issues

The following table summanzes noncompliance issues for the closure of the Sunnse Mountain Landfill as govemed by applicable regulations

Table 6.0-1. Closure Noncompliance Issues

Issue I Closure

A Cover

1 Bamer I .ayer

Reason Cover not acceptable Thickness does not meet minimum required Does not meet hydraulic conductivity requirement

Regulation 40CFR258 60 40CFR258 60(a)

40CFR258 60(a)(1)

25


2 Erosion Layer n Safety

A Gas emissions

Does not exist m areas Gas emissions excessive Emissions exceed 25% of lower explosive hmit in areas

40CFR258 60(a)(3) 40CFR257 3-8 40CFR257 3-8(a)(l)

The followmg issues may or may not be govemed by 40CFR258 due to uncertainty over whether the entire landfill should fall under this set of regulations Because waste was accepted after October 9, 1991, the entire landfill may be subject to 40CFR258, not just those areas that accepted waste between October 9, 1991, and October 9, 1993 One issue to be considered is the fact that it may be possible for percolation that entered through an area of the landfill that was not closed according to 40CFR258 to create leachate that affects areas that accepted waste after October 9, 1991 In other words, if the vanous waste cells are not physically isolated from one another, the entire landfill could be considered a single waste cell thus requinng a cover over the entire landfill

Table 6.0-2. Potential Closure Noncompliance Issues

Issue I Momtonng

A Gas momtonng

B Groundwater momtonng

II Leachate Collection

in Fmcincial Assurance Mechanism

rv Gas emissions

Reason Does not exist Does not exist

Does not exist

Does not exist

Does not exist

May exceed allowable limits and quality (definitive analysis yet to be performed)

Regulation/Agreement

Sunnse Mountain Landfill Closure Plan (Agreement with Clark County) document Regulatory Compliance Audit Report, Sunnse Mountam Landfill, l^s Vegas, NV Sunnse Mountain Landfill Expansion document Regulatory Compliance Audit Report, Sunnse Mountain Landfill, Las Vegas, NV Clean Air Act, 40CFR60 Subpart Cc '>

the Distnct Board of Health information

of Clark County Refer to Attachment E for memos and related

7 0 Recommendations for BLM Consideration

7 1 Gas Emissions

26


The gas etmssion problem is a concem that should be addressed immediately The amount and type of gas escaping should be analyzed If there is an immediate health hazard, this should be remedied before other issues are addressed The gas escaping the landfill should be contiolled Two gas conttol strategies ~ passive and active — are available Passive systems provide comdors to intercept lateral gas nugration and channel the gas to a collection point or a vent Active systems generate a zone of negative pressure to increase the pressure gradient and, consequently, the flow toward the zone

7 2 Maintenance of existmg cap The existing cap needs to have a regular maintenance schedule to repair continued damage due to surface cracking and erosion Surface depressions created by differential settlement must be filled with additional soil placed in accordance with the cover requirements set forth m 40CFR258 60

7 3 Existing Cover The existing cap does not meet cover requirements outlined in 40CFR258 or the approved closure plan (Sunnse Mountain Landfill Closure Plan) The cover that does exist should be considered no more than an intermediate cap to be covered with a final cover If desured, the final cover installation could be delayed until after significant differential settlement has ceased An intermediate cover can be used in the intenm Areas not covered with an intenm cover should be covered with one if this option is chosen

7 4 Final Cover Installation A final cover should be installed over the landfill that meets requirements set forth in 40CFR258 An informed decision should be made on whether to cover only the areas ofthe landfill that accepted waste between October 9, 1991, and October 9, 1993, as the Sunnse Mountain Landfill Closure Plan suggests, or covenng the entire landfill Consideration should be given to the fact that the percolation entenng through surfaces not covered by this final cover could migrate into and through areas that are covered

7 5 Groundwater Momtonng Groundwater momtonng wells should be installed to monitor for possible contaminant migration through leachate escaping the landfill A pnmary function of a landfill cover is to minimize infiltration and thus rmnimize the generation of leachate Because only pomons of the landfill were to be closed per 40CFR258, this logically increases the potential for infilttation and consequently the need for groundwater momtonng The noncompliance of the existing cover further warrants the need for groundwater momtonng Consideration should be given for momtonng water quality upgradient of the landfill for comparison to contaminant concentrations found downstteam

7 6 Rework of the surface drainage system

27


Elimination of the cormgated metal culverts should be considered, perhaps replacing them with lined ditches After mstallation of the final cover, the surface should be covered with an armored surface to mimiriize erosion of the final cover This armored surface could consist of 6-inches of compacted soil covered with a thin layer (one or two-inches thick) layer of gravel (3/4-mch to 2-inch diameter) Another choice for the armored surface could consist of a six-inch thick layer of soil uniformly mixed with gravel (25% by weight)

7 7 Complete Analysis of Site A complete and detailed analysis should be performed on the entire landfill site to assess the cunent situation and identify the full envelope of issues to be addressed at the site The findings of this effort are sigmficant and found upon only a cursory review of the landfill condition Such findings wanant further comprehensive analysis of the overall condition of the landfill

8 0 References

1 Code of Federal Regulations, Title 40, Subpart 257

2 Code of Federal Regulations, Title 40, Subpart 258

3 Environmentai Protection Agency 1991 Seminar Publication "Design and Constinction of RCRA/CERCLA Final Covers" EPPJ625/4-91/025

4 Francis, Richard E , Richard Aguilar 1995 "Calcium Carbonate Effects on Soil Textural Class in Senuand Wildland Soils" And Soil Research and Rehabilitation, Volume 9, pip 155-165

28


Attachment A

Clark County Health District

Quality Control Documentation

29


Stephen F. Dwyer, PE ;LCe^u~r..f

October 13, 1997

David Rowles, Director of Administration

Dear Mr Rowles

I spoke with Victor Skaar who informed me that I need to contact you to request needed documentation I would like to request copies of ail quality control documenta on, photographs, soil test data, etc for the construction of the final closure of the Sunnse Mountain Landfill outside of Las Vegas, Nevada Please send the quality control documentation to

Steve Dwyer

13140 Blackstone Rd NE

Albuquerque, NM 87111

Thank you,

Stephen F Dwyer

^0

Stephen F. Dwyer, PE 13140 BlacKXtoneRd NE

Aibuquarque NM 87111

October 13.1997

David Rowtes, Director of Administration

Dear Mr Rowles

I spoke with Victor Skaar who informed me that I need to contact you to request needed documentation I would like to request copies of ali quality control documentation, photographs, soil test data, etc for the constmction of the final closure of the Sunnse Mountain Landfill outside of Las Vegas, Nevada Please send the quality control documentation to

Steve Dwyer

13140 Blackstone Rd NE

AltxKjuerque, NM 87111

Thank you.

Stephen F Dwyer

Hard ing L a w s o n A s s o c i a t e s

March 22, 1995

28629 1

Mr Tom Isola, Vice President Mr George Rogers, Architect Disposal Urban Maintenance Processing Company, Inc 770 E Sahara Avenue Las Vegas Nevada 89104

VERIFICATION OF CLOSURE IN ACCORDANCE WITH APPROVED CLOSURE PLAN SUNRISE MOUNTAIN LANDFILL CLARK COUNTY, NEVADA

Gentlemen

At vour request this letter is submitted as venfication of closure ofthe above referenced landfill in accord with the approved landfill closure plan dated Apnl 14 1994 and titled, "Sunnse Mountam Landfill Closure Plan " This venfication IS required by Section 7 1 of the approved closure plan and further required by Clark County and Slate of Nevada Administrative Codes Section 444 6892-6 and by the Code of Federal Regulations, Part 258 60. Section (h)

Ai part ol the venficalion process, an engineer of Harding Lawson Associates (I-ILA) visited the site on seven separate occasions during construction phase activities to review progress and assist in identifying construction deficiencies which were required to be addressed pnor to finalizing closure Venfication of meeting closure plan requu-ements is also based on information provided to HLA which included the following documents

• Letter and reports by Vector Engineering Inc , the engmeenng consulating firm providmg the construction qualitv assurance oversight for the installation of the infiltration layer and erosion layer The letter, copy attached, provides certification regardmg compliance with the approved plans and specifications for the infiltration layer system

• Record survey supplied by Silver State Disposal Company showmg compliance with thickness requirements for the installation ofthe infiltration layer and erosion layer system

Based on the HLA site visits, and on the above referenced documents designed structures and engmeered matenals appear lo ha\e been installed in substantial accord with the approved closure plan and appear to meet the design mtent This leiler was prepared in accord with generally accepted practices applicable at the lime it was issued HLA makes no other warranties either expressed or implied as to the professional opimon provided under the terms of service as dcscnbed in this letter

HLA sincerely appreciates the opportunity to provide continued service to DUMPCo in completion of this project. Should there be qucsuons regarding this letter or should you require additional information please contact the undersigned at (702) 251 -5449 - - - - ^ .

Sincerely HARDING LAWSON ASSOCL^TES

.J^:^-.^^'^^^^^ Edward H Martinez P E Associate Engmeer Certified Envirorunental Manager EM-1013 (NV] "'^!^ ' '/j -jr ' - 7 ^ y '

EHM/em - attachments 2 ^ "2 "Z- ' f ^

Engineering and 4170 South Decalur Boulevard Suite A 1 Las Vegas NV B9103 702/2515449 Environmental Serv ices l. Subsidiary of Harding Associates Offices Nattonuride

CERTIFICATION OF COMPUANCE

Based on Vector's observation and testing dunng the construction of the structural fill

and infiltration cover layer, it is our opimon that the earthen matenals used to

construct these capping layers over the one hundred twenty mne (129) acre closure

area -were placed in general accordance -with the project plans and specifications

The undersigned hereby cenifies that the geotechnical aspects of structural fill and

infiltration layer components of final closure cap at the Sunnse Mountam Landfill, Las

Vegas, Ne-vada meet the intent of the technical speafications of the project

The information contained in this document was prepared by Vector Engineenng, Inc

in accordance -with generally accepted soils engineenng practices applicable at the

time, for the sole use of D U M P Co Vector Engineenng, Inc makes no other

warranues, either expressed or implied, as to the professional ad-vice pro-vided under

the terms of this agreement, and as descnbed in this report

The field and laboratory testing and observations were performed under the direction

of a registered ci-vnl engineer hcensed in the state of Ne-vada

Thomas Woodward, P E Vector Engineenng, Inc Director, Solid Waste Engi

Stfipneal Irfaan iiamtFttanre

lDltiE[io\^Ll

" MAR 1 0 1995

D'rcajr Or/.rormGnfalHcallhDiVLsiT March 3, 1995 Mr Clare Sclimutz, R S

Clark County Health Distnct 625 Shadow Lsine Las Vegas, Nevada 89127

re Sunnse Mountain Landfill Closure

Dear Mr Sclimutz,

Please accept this letter as notification that tlie Sunrise Mountam Landfill is fully closed as of March 1, 1995 according to the terms and conditions as noted in part 7 1 ofthe document titled "Sunrise Mountam Landfill Closure Plan" dated Apnl 14, 1994, agreed to by you and other agencies party thereto Furthermore understand that no additional closure activities are required except momtonng and maintenance As of March I, 1995 D U M P C o will begin momtonng and maintenance ofthe closure for a penod of five years, until April 31, 2000, as agreed to in part 8 1 1 of the aforementioned plan

Please acknowledge your understanding and agreement of this notification by signing and dating where required and returmng one original copy to us for our files

Very tiuly yours.

y y ~ ^ : ^

Thomas A Isola Vice President

Clark County Health District Date

7G ast Sahara Avenue • P O Box 98508 • Las Vegas, Nevada 89193-8508 • Telephone (702) 735-5151 • Fax (702) 735-1986

Sunrise Mountam Landfill Construction Quality Assurance Plan

Prepared for

Disposal Urban Mamtenance Processing Company, Inc Clark County, Nevada

HLA Project No ^ 0 7 3

erry A Hester P E Principal Engineer

April 14 1994

Harding Lawson Associates Engineenng and Environmentai Services 4170 S Decatur Boulevard, Suite A-1 Las Vegas, Nevada 89103 - (702)251-5449

TABLE OF CONTENTS

1 0 SCOPE AND INTENT

2 0 PARTIES 2 1 Opera tor 2 2 Resident Project Representative

2 2 1 Responsibilibes 2 2 2 Qualifications

2 3 Design Enguieer 2 3 1 Responsibditaes 2 2 3 2 Qualificataons 2 2 3 3 Submittals 2

2 4 Contractor 2 2 4 1 Responsibilibes 2 2 4 2 Qualificabons 2 2 4 3 Submittals •7

2 5 CQA Consultant 3 2 5 1 Responsibilibes 3 2 5 2 Qual i i icabons 3 2 5 3 Submittals 3

2 6 CQA Laboratory 4 2 6 2 Qualif icabons 4 2 6 3 Submittals 4

3 0 PROJECT MEETINGS 4 3 1 Pre-Construcbon Meeting 4 3 2 Periodic Progress Meetmgs 5 3 3 Problem or Work Deficiency Meetmg 5

4 0 DOCUMENTATION 5 4 1 Daily Record Keeping and Reportmg 6 4 2 Acceptance Reports 6 4 3 Fmal Documentabon 6

5 0 INSPECTION ACTIVITIES 7 5 1 Sbnc tu r a l Fill 7

5 1 1 Pre-construcbon " 5 1 2 Conformance Testing 7 5 1 3 Construcbon 8 5 1 4 Construcbon Testmg 8 5 1 5 Defects and Repairs 9 5 1 6 Post-Construcbon 9

5 2 Low Permeabili ty Material 10 5 2 1 Pre-Construcbon 10 5 ^ 2 Conformance Tesbng 11 5 2 3 Construcbon 12 5 2 4 Construcbon Testmg 12 5 2 5 Defects and Repairs 13 5 2 6 Post-construcbon 14

5 3 Erosion Layer 14 5 3 1 Pre-Construcbon 14 5 3 2 Construcbon 14 5 3 3 Defects and Repairs 15

DISTRIBUTION

Sunrise Mountain LandfiU Constmct ion Quality Assurance Plan

1.0 SCOPE AND INTENT 2.1 O p e r a t o r

This Construction Qualitv Assurance Plan (CQAP) presents quality assuiance and control procedures for closure of Sunrise Mountain Landfill ui Qark County Nevada The CQAP is a planned system of activities and mspecticns to monitor and control quality of construction to venfy the landfill is closed as mlended The CQAP shall be used m conjunction with project drawings and specifications which have been prepared to meet or exceed applicable local state and federal regulatory requuements

This CQAP provides a means for mdependent third-party verification that activities related to installation of the fmal cover and cap materials at Sunrise Mountam Landfill meets or exceeds requiremants of the plans specifications, and apphcable regulations This CQAP is not mtended to replace contractual roles of the Contractor and/or Operator which are established in plans, specifications and other contract documents

This document was prepared by Hardmg Lawson Associates (HLA) for the sole use of Disposal Urban Mamtenance Processing Company Inc (D U M P Co ) and regulatory agencies directly mvolved m this project the onlv mtended beneficiaries of our work No other party should rely on information contained herein without prior uTitten consent of D U M P Co and HLA

Typical Imes of communicalion for qualitv assmcuice issues on this pioject aie illustrated m Figure 11 It should be noted this figure depicts lecommended flow of communication only and does not necessarilv indicate contractual relationships between listed paities The CQA Consultant shall be capable of direct communication with the RPR at all times

2.0 PARTIES

This section ouUmes roles responsibilities and qualifications of parties associated with the operation design, quality assurance construction and matenals for closure of the landfdl An mdividual or firm may fulfill more than one role unless stated othervt-ise m the followmg sections

The Operator of tlie facility is Disposal Uiban Mamtenance Processmg Company Inc of Las Vegas Nevada The Operatoi is lesponsible for design, permittmg and construction necessars' for closm-e of the Sunnse Mountam Landfill This responsibdity mcludes complymg with requirements of the permittmg agency and assuring the permittmg agency, by submission of the CQA documentaUon the facditv was closed m accordance with the plans and specifications

2.2 Resident Project Representative

The Resident Project Representative (RPR) is the official representaUve of the Operatoi v;no shall coordinate closure activities for the project The RPR may be an employee oi llie Operator

2.2.1 R e s p o n s i b i l i t i e s

The RPR IS responsible for coordinating construction and CQA activities, and for organizmg and unplementmg the CQA Plan for the project As comimunication coordinator, the RPR shall act as a liaison between the parties mvolved m the closure to assure communications are mamtamed. The RPR shall also be responsible for resolving quality assurance issues that arise durmg closure

2.2.2 Qual i f icat ions

The selection of the RPR is the lesponsibiiity of the Operator QucJifications for this position include familiarity with the followmg

Applicable eailhwoik construction and landfill closuie technioues

• Applicable legulatoiA' lequiiements

Policies and piocediues foi pioject management

2.3 Design Engineer

The Engmeer is the mdividual or fum responsible for preparation of the closure plans construction plans specifications and CQAP The Design Engmeer will be contracted by the Operatoi and

DUMPCO/HLAOigsAcl Harding Lawson Associates

Sunrise Mountain Landfi l l Construct ion Quality Assurance Plan

as such may act when necessai v as the Oneialoi s representative

2.3.1 Respons ib i l i t i es

The Design Engmeer is responsible for developmg the engmeermg design and preparmg the associated construcbon drawmgs and specifications for closure of the landfill The Design Engmeer is responsible for approvmg design and specification changes and makmg design clarifications necessitated durmg closure activities

2.3.2 Qual i f ica t ions

The Design Engmeer shall be a qualified professional engmeer registered as a Civil Engineer m the State of Nevada The Design Engmeer shaU be familiar with the followmg

• Geotechmcal design methods and procedures

• EvaluaUon, use. and testmg of sods for earth construction

Applicable regulatorv lequirements

• The practical, technical and managerial expenence necessary for the develooment of construction plans

2.3.3 Submittals

The Design Engmeer is responsible for the followmg project documents

• Project construction drawmgs and specifications

Associated engmeermg leporls and calculations

• Approved and unapproved design change forms when requested

2-4 C o n t r a c t o r

The followmg subsections describe the general requirement for the project contractor

2.4.1 Respons ib i l i t i e s

The ConUactor is lesponsible foi tiio scojio of work estabhshed by tlie Operatoi m tlie conuact documents This work will be pei-formod m conformance with the construction drawmgs and specifications and will use necessary construction techniques and procedures to implement the closure plan The Contractor shall be responsible for locatmg and transportmg required products and matenals to and withm the site In the majonty of instances for this project the Operator will act as Contractor Exceptions to this are for specialty construction services as designated bv the Operator

2.4J2 Qual i f ica t ions

The Contractor shall

• Qualified and approved by the Operator when applicable

• Able to provide qualified persoimel to meet the demands of the project

Have practical and professional expenence m earthwork consti-uction and material processmg

2.4.3 S u b m i t t a l s

When applicable to be considered for qualification the Contractor shall typically provide the foUovnng information to the Operator Information to be requested by the Operator is at the Operator's discretion Actual qualification jequiiements will be mcluded m the contract documents

Contractor backgiound cmd information

• Bondmg capability

A list of outstandmg contracts

A list of at least three comparable projects with the followmg information

Name of the facility its location and date of construction

D UMPCO/HLAO iga/kcl Hardinq Lawson Associates

Sunrise Mountain LandfiU Construction Quality Assurance Plan

2.5

Name of pioject manager oi contact person foi each project

Description and purpose of construction and defmition of contractor's scope of work

A list of reatiily available equipment used to perform the work (such as scrapers graders scarifiers, compactors diskmg equipment and water trucks)

Resume of the Project Manager to be assigned to this project mcludmg the duration ol employment vwth the Contractor

A schedule of proposed project assigned activities

CQA C o n s u l t a n t

The CQA Consultant is the firm or mchvidual, acting on behalf of the Operator, responsible for observmg, testmg and documentmg activities related to quality assurance durmg closme activities of this project The CQA Consultant shall be mdependent of the Contractoi and/oi Operator The CQA Officer shall represent the CQA Consultant at the site and on this project The CQA Officer shall provide tramed field persormel lo provide support durmg CQA acti\ ities, if necessary

2.5.1 Respons ib i l i t i e s

The CQA Consultant shall be responsible for observing and documentmg acUvities ielated to quality assurance of the landfdl closuie The CQA Consultant shall issue a Nevada legisteied professional engmeei-sealed certification ieport at pioject completion The CQA Consultant shall oversee soil and laboratory testmg and shall review project-related documents The CQA Consultant shall observe and document activities ol the Contractor/Operator m sufficient detail, and with sufficient contmuity, to provide a level of confidence that the work product complies with design drawmgs and specifications The CQA Consultant shall also verify that construction requirements were met and that requiied submittals were provided In addition the CQA Consultant shall have performed and repealed

observations and Ic^ls as necessary lo pro\iae a high degree of ccrlamtv that physical and mechanical chaiaclenstics of project components meet oi exceed specifications

The CQA Consultant shall issue weekly reports of quality assurance activities to the RPR These reports shall mclude visual observations and test results, and shall note any deviations from the CQA Plan Construction reports summariamg significant events and addressmg all problems encoimtered and their solutions shall be penodically issued to the RPR The frequency of these reports shall be established at the preconstruction meetmg

Differences between the CQA Consultant's interpretation of design drawmgs and specifications and the Contractor's/Operators work shall be properly and adequately assessed as soon as they come to the CQA Consultant's attention If assessment mdicates actual or suspected work deficiencies, the CQA Consultant shall inform the Contractor/Operator and RPR of these oeficiencies The CQA Consultant shall be responsible for rejectmg defective work and veiifymg implementation of corrective measures The CQA Consultant will leview mteraction u ilh and lesults from the CQA Laboratory

2.5.2 Qual i f ica t ions

The CQA Consultant shall be approvea by the Operator The CQA Consultant shall be experienced m preparmg quality assurance documentation including quality assurance forms reports and certifications The CQA Consultant shall have formal academic trammg m civil engmeermg or a closely related discipline oi defendable experience and qualifications in construction oversight and shall be registered as a professional engineer m the Stale of Nevada The CQA Consultant shall have specific U-ammg in construction quality assurance of engmeered soil systems shall have currenl health and safely trammg m accordance with 29 CFR 1910 120, and ll is desirable that the CQA Consultants have expenence m landfills

2.5.3 Submittals

For qualification the CQA Consultant shall provide the followmg infonnaUon to the Operator

DUMPCOyHLA0198/lccl Harding Lawson Associates

Sunrise Mountain Landfil l Construction Quali ty Assurance Plan

A summary of the CQA Consultant's experience m quality assurance for landfiUs or other engmeered soil systems

A summary of quality assurance documentaUon and methods used by tho CQA Consultant mcludmg sample quality assurance forms, reports certifications and example CQA Plans prepared by the CQA Consultant

• Resumes of persormel lo be mvolved m the project

Proof of current professional engmeermg registration m the State of Nevada

2.6 CQA Labo ra to ry

The CQA Laboratory is a firm, mdependent of the Operator and/or Contractor, responsible for conducting tests on cover materials used at the site The laboratory will work tmder the direct supervision of the CQA Consultant

2.6.1 Respons ib i l i t i es

The CQA Laboratory shall conduct appropriate laboratory tests, as directed by the CQA Consultant Test procedures shall be performed m accordance with test methods oudmed m this CQA Plan The CQA Laboratory shall provide wTitlen test results as outlmed m Section 2 6 3

2.6.2 Qual i f icat ions

The CQA Laboratory shall be staffed with experienced technicians properly equipped and fully qualified lo perform the tests m accordance with the specified standards and shall have appropriate testmg equipment propeily maintamed and calibrated Laboratory persormel shall be familiar with American Society lor Testmg and Matenals (ASTM), Federal Test Method Standartis (FTMS), National Sanitation Founidation (NSF), Amencan Association of Slate Highway and Transportation Officials (AASHTO) Umted States Army Corps of Engmeers and other applicable test standards as required The CQA Laboratory shall be capable of providing test results withm project deadlmes throughout landfdl closure

2.6.3 S u b m i t t a l s

Tha CQA Laboratory shall submit test lesulls lo the CQA Consultant withm the deadlines agiood upon at the pre-conslruclion meetmg Written test results shall be m a logical format and shall mclude references lo standard test methoids used

3 0 PROJECT MEETINGS

Meetmgs shall be held Ihioughout the duration of construction closure activiUes to enhance communication and lo ensure familiarity of all aspects of the construction by the parties involved These meetmgs shall familiarize the parties mvolved m closure acliviUes with project design specifications construcbon procedures and any recent design changes The extent of project meetings will vary dependmg upon the stage or the projects The follovymg meetmgs will be conducted dunng the development of the project

• Pre-construction meeting

Periodic progress meetmgs

• Problem or work deficiency meetmgs (as needed)

3.1 P r e - C o n s t r u c t i o n M e e t i n g

A pre-construction meetmg shall be held pnor to commencement of any construction activity This meetmg shall be attended by the RPR Design Engmeer, Contractor/Operator and CQA Consultant and Laboraton- or their lepi-esenlatives The purpose of this meetmg is to lesolve any imcertamties regaidmg this CQA Plan design specifications and drawmgs or construction procedures The pie-construclion meetmg will also be used to

Identify parties and theu specific responsibilities

Provide each party with relevant CQA documentation and supporting mformaUon

DUMPCO/HLA0198Acl H a r d i n g L a w s o n A s s o c i a t e s

Sunrise Mountain Landfi l l Construction Quality Assurance Plan

Familiarize each party with the CQA Plan as It relates to the design and specifications

• Discuss changes to the CQA Plan needed lo meet or exceed the specified design

Review Imes of authonty and communication for each party

• Discuss protocol for field observations and field tests

• Discuss protocol for handlmg construction deficiencies repau work and relesling

• Review protocol for documentmg reportmg handlmg, distributmg and 5lormg of mspection data

• Review work area security and safely protocol

• Discuss procedures for locatmg and protectmg construction materials and for proleclmg these malenals from damage due lo mclement weather oi othei adverse events

• Review the project schedule

Site walk lo review storage locations for construction material construction equipment and inspection eqmpment will also be conducted The pre-construction meetmg shall be documented by the CQA Consultant mmules of this meetmg shall be transmitted to atlendmg parties

3-2 Pe r i od i c P r o g r e s s M e e t i n g s

A progress meetmg shall be held at a minimum of once per week lo discuss cmTent and potential issues about closure The frequency of these progress meetmgs may be modified al the discretion of the CQA Consultant and the RPR, dependmg upon the lype of construction activity bemg conducted The RPR, CQA Consultant and Contractor/Operator shall attend the progress meetings The purpose of these meetmgs is lo

• Review activities and accomplishments since the last meetmg

3 .3

Review upcoming work locations and activities

Identify Contractor's upcommg personnel and equipment assignments

Discuss any potential construction problems

Defme and discuss problems or deficiencies

Review alternative solutions

Adopt plans lo resolve problems or deficiencies

P r o b l e m or Work D e f i c i e n c y M e e t i n g

Meetmgs to discuss and resolve problems or work deficiencies shall be held as needed These meetmgs shall be attended by the RPR CQA Consultant, Contractor/Operator and other Problem or Work Deficiency Meetmg parties affected by the problem The purpose of a problem or work deficiency meetmg is lo identify a problem or deficiency m the constniciion work, review alternative solutions and select and implement a plan to resolve the problem or deficiency The CQA Consultant shall document the meetmgs and transmit mmutes to attending parties

4.0 DOCUMENTATION

The CQA Consultant shall documeni that requirements in consUTiction diawmgs specifications and CQA Plan have been addressed and satisfied The CQA Consultant shall piovide the RPR with signed descriptive remarks data sheets and checklists to verify monitormg activities have been carried out The CQA Consultant shall also mamtam a complete file of documents at the job site which mcludes the CQA Plan, checklists, lest procedures daily logs and other pertment documents The RPR shall provide safe and accessible storage for these and any other project documents

niiMprn/Hi Ani98/kcl Hardina Lawson Associates

Sunrise Mountain Landfill Construct ion Quality Assurance Plan

4.1 Daily Record Keeping and Reporting

A daily summary report shall be prepared along with supporting mspection notes drawings photographs and records for each day that construction mspection and testmg activities occur at the site The CQA Consultant shall prepare a chronological daily summary report which mcludes the followmg

• Identifying sheet number for cross-referencmg and document contiol

Dale name of project and location

• Weather and site conditions

• Summary of any meetmgs conducted and a sjimmarv oi items discussed at those meetmgs

• Location of daily construction activities and progress

• Record of equipment and persormel working in a particular area

• Record of all mspecUon activities and lest reports

Location of work bemg tested and areas passmg fmal mspection

• Record of anything which does nol meel specified designs Corrective action measures and results shall also be recorded

• Description of anv materials received at the site and tlie condition m which they were received

• Record of equipment calibrations or recalibrations of test equipment and any actions taken as a result of recalibration

• Record of any communication between the CQA Consultant and the RPR

Record of site visits by non-project persons with names and affiliations

• Identification of construction pioblcms

and their solution or disposition

Signature of the CQA Consultant

4.2 Acceptance Reports Following the completion of certam milestones of the closure activities such as completion of the mfiltralion layer the CQA Consultant shall prepare an acceptance report for die completed task These reports shall mdicaie the work has been approved as completed accordmg lo design and specifications of the closure plan Still photography shall be used to document appearance of the completed task These reports shall be appended to the Fmal Construction Report which will be submitted to the Operator

4.3 Final D o c u m e n t a t i o n

At completion of closure activities, the CQA Consultant shall prepare and send a Fmal Construction Report to the Operator for submittal lo applicable regulatory agencies The purpose of the fmal documentation is lo provide written evidence the CQA Plan was implemented as proposed and construction proceeded m accordance with applicable oesign criteria, construction plans and specifications This report shall mclude the followmg

A narrauve desciibmg (al a mmimum) the project project design team CQA personnel Contractor(s)/Operalor field mspection operations and any unusual conditions encountered

Daily inspection summan reports

Acceptance lepoi is

• Deviations fiom design and material specificalions (with justifymg documentation)

• Construction record areal survey (lo be supplied by owmer)

Fmal design drawings

Testmg results

niiMprn/i-n AmoR/Wrl Hardina Lawson Associates

S u n n s e M o u n t a i n Land f i l l C o n s t r u c t i o n Qua l i t y A s s u r a n c e P lan

Tho CQA Consultant shall certify in writing that to the extent known components of this project were built or installed according lo design plans and specifications This certification shall be included in the final documentaUon sent to the Operator for submittal to applicable regulatorv agencies

5.0 INSPECTION ACTIVITIES

This section describes field mspection activities includmg observauons and tests which shall be performed by the CQA Consultant durmg closure of the landfill The mspection activities for each phase of the closure will be specifically applicable only lo those components of the closure which they address The discussion of each component IS further subdivided mto sections on preconstruction construction and post-construction mspection activities unique lo that component

Inspection activities shall be performed by the CQA Consultant to venfy the landfill has been closed lo meel or exceed design criteria, drawmgs and specificalions Inspection acliviUes mclude conformance testmg, field observation and testing and any necessary lepau procedures The CQA Consultant has the authority lo revise testmg and inspection procedures or frequencies lo address actual field conditions Any revisions will be brought to the attention of the RPR as soon as practical

5-1.1 Pre-construction

Pre construction activities shall be pcifonncd lo piovide an understanding of woik activities design and construction requuements material properties and construction melhods necessary lo meet design requirements of the structural fill layer To accomplish this a pre-conslruclion meetmg shall be held between the Contractor/Operatoi the Design Engmeei and the CQA Consultant as needed Structural fill laver materials shall be tested, prior lo placement for material properties and durmg and afler placement for peiformance properties ConstmcUon procedm^es shall be established with the goal of meetmg or exceeding design lequiiements Pie-construction activities of the CQA Consultant shall mclude the followmg

• Review oi construction plans and specificalions associated with construction of the structural fill layer

InspecUon of stockpiles or borrow site of the structural fill layer material for uniforrmtv and the presence of unsuitable matenals

Review of ?\ailable laboratorv' testmg reports foi ..he structural fill layer materials

• Review of the Contractors work scheaule

Durmg pre-construction activities the CQA Consultant shall review design drawmgs and specifications of each component for clai itv The CQA Consultant may conduct a pie-construction mformaUon session with the Contractoi/Opeialoi to familial ize him with specified design inspection policies and piocedures

5.1 Structural Fill

Structural fill mspection activities shall be required for all matenal which is placed on top of the mlermediale cover lo level the surface to wiihm acceptable tolerance of the design drawmgs for placement of the fmal cover

5 1.2 Conformance Testing

The CQA Consultant shall oblam one sample per 10 000 cubic vaids (cy) of structm-al fill lavei maieiial placed oi moie fiequendy based on visual soil change The sample size shall be Iwo 5 gallon buckets or the equivalent volume in sample bags The CQA laboiatoi-y shall peifonn a particle size analysis and a soil classification on each sample taken

• Moisture-density re la t ionship (compaction curve ASTM D 1557)

Particle size analvsis (ASTM D 422)

Soil classification (ASTM D 2487)

niTMprn/Hi Am9B/kcl H a r d i n q L a w s o n A s s o c i a t e s

Sunrise Mountain Landfil l Construction Quality Assurance Plan

The CQA Consultant shall review tlie moislure-densily relationship test results and determme the moisture content and soil densitv which provides the relative compaction for each grouping or classificaUon of soils as requued m the drawmgs and specifications The CQA Consultant shall also review the particle size analysis and sod classificaUon results for uniformity with field testmg and to determme if results meet specification requirements The CQA Consultant shall report any nonconformance lo the RPR and the Contractor/Operator The locations and dales of all samplmg shall be recorded m the CQA Consultant's dady summary report

5.1.3 Cons t ruc t ion

Observation and mspection of the placement of the structural fill laver shall be coordinated with overall construction testing Acceptance cntena for construction work shall be as identified m project specifications The CQA Consultant shall observe, inspect and document the followmg durmg construction of the structural fill layer

• Water content and consistency of soil durmg processmg placement and compaction

Type and level of typical compactive effort

Roller type

Roller weight

Number of passes

^cllon of compaction eauipment on the sod surface (sheepsfool peneUalion pumpmg crackmg)

Maximum clod size

Contdition of soil stockpile

Loose and compacted lift thickness

Melhod of meshmg the lifls together

Dimensions of the compacted embankment

Aieas wheie damage may have occunod due to excess or insufficient moisture

5.1.4 Cons t ruc t i on Tes t ing

Construction quality assurance testmg shall be conducted m accordance with the project specifications Field and laboratory tests shall be conducted on samples taken from the structura] fill durmg the course of construction work Testmg and samplmg procedures shall be observed and documented bv the CQA Consultant for compliance with procedures listed m SecUons 5 14 1 and 5 14 2

5.1.4.1 Field Tes t ing

The CQA Consultant shall perform the followmg field tests on each lift of the compacted soil

Field Moisture Content (ASTM D2216)

Field Density (ASTM D1556 D2922, D2937, D2167), use one method only

Unless otherwise specified m the project specifications field densities shall be performed each lift at a fiequency of one per every 40 000 squaie feet of compacted matenal with a minimum of 2 tests per day bemg performed Field moisture content shall be performed al a frequency of one per every 10 field densities with a minimum of one test per day Sample locations shall be selected by the CQA Consultant

The nuclear density lest method (ASTM D2922) shall be the preferred method of density testmg The locaUon of roulme m-place density tests shall be detei mined usmg a non-biased sampling plan based on statistically landom selection of testing locaUons Questionable results for any smgle lest shall be addi^essed by relestmg m the same general location Penodic checks (typically a mmimum of once per day) usmg the sand-cone method (ASTM D1556) or rubber balloon method (ASTM D2167) may be performed lo venfy the nuclear lest results

As directed by the RPR, perforations of slrucluxal fdl shall be backfdled Perforations that must be backfilled shall mclude but are not limited to the followmg

ni IMPCO/H]-A0198Ad Harding Lawson Associates


Nuclear densiu test piobe locations

Sand-cone lest locations

PerforaUons shall be backfilled and be compaclod with a lamping rod, modified or standard Procioi hammer or a hand tamper Al a mmimum the CQA Consultant shall perform routine tests and observations on the backfilled areas

An mcreased frequency of testmg shall be used upon recommendation from the CQA Consultant and approval from the RPR, if one or more of the followmg conditions develop durmg construction

Lift thickness is greater than specified

• The structural fdl material has an improper or variable moisture content

• The degree of comoaction of the matei lal IS suspect

Additional testing may also be considered by the CQA Consultant and RPR when

• Weather conditions are adveise

Rollers have not used optimum ballast

• Equipment breaks down frequently

Gradmg is being started or finished

5 1.5 D e f e c t s a n d Repa i r s

Acceptability cntena for testing shall be as identified m project specifications At locations wheie testmg indicates lequiiements of the project specifications aie nol met the CQA Consultant shall determine the extent and natuie of the defect and recommend coirective actions lo the RPR

After determmmg the extent and nature of a defect the CQA Consultant shall promptly notify the Contractor and the RPR As needed a meetmg mvolvmg the Contractor/Operator CQA Consultant RPR and other appropnate parties should be held to assess the problem review alternative solutions and implement a response plan

The Contractoi/Opcidloi shall icjiaii <ili deficiencies to meet ihe pioject specifications If a project specification cntenon cannot bo mel because of unusual wealhci oi olhei conditions the CQA Consultant or Design Enginoei shall develop and present to the RPR possible solutions for his approval

The CQA Consultant shall rolest deficienl aieas followmg repair of the reported defect All reiests by the CQA Consultant shall verify the defect has been conected before additional work is performed by the Contiaclor/Operator in the area of the deficiency Fmally the CQA Consultant shall observe repair work and report anv noncompliance with tho above requirements in wrilmg lo the RPR

5.1.6 Post-Construction

A post-construction inspecUon shall be conducted by the CQA Consultant upon completion of the structural fill layer The purpose of this mspection shall be lo identify those areas that might require conective action bv the Contiaclor/Operator The mspection shall occur pnor lo placement of matenal over the structuial fdl layer The CQA Consultant shall inspec! the structural fill layer foi the followmg

• Low spots or depressions which uould cause water to pond on the landfill

Areas damaged oi improperly compacted

Areas excessively eroded by ramfall oi other means dunng the construction period 01 as a lesull of constiuclion activities

Large inegulaiities oi pioUusions in the slrucluial fdl lavei grade resulting fiom rocks slicks giade slakes ciacks and excess material placement

In addition the CQA Consultant shall review lesults of a constinction record survey arranged for by the contractor/owner to verify the structural fill layer has been placed to wilhm acceptable tolerances of design grades and slopes

mTv/TV-r^n.r^ AniQtt/l.r.1 Hardina Lawson Associates

Sunrise Mountain Landfil l Construct ion Quality Assurance Plan

5.2 Low Permeabil ity Material

Low permeability material shall be used foi tlie low-permeabililv layer of tho landfill final covci system Low permeability material shall consist of clean select matenal free of trash oi games excessive large particles, or other deleterious matter Soils proposed for construction shall be classified accordmg to the Unified Sod Classification System and shall be capable of a placed hydraulic conducbvity of 1 x 10 ' cmysec or less Soils with a visibly identifiable organic content, or soils classified as organic sill or clay (OL,OH), shall not be used as low permeability material

5.2.1 Pre-Construction

Pre-construction activities of the CQA Consultant shall mclude

• Review of design drawmgs and specifications associated with construction of the low permeability matenal layer

• Review of Contractoi s/Operaloi s woik schedule

• Review of construction methods and equipment to be used for placement of the low permeability lavei

• Inspection of the stock piles oi bonow site of the low permeability laver material for uniformity and the presence of unsuitable materials

• Review of existing laboiatoiT testmg reports for the low peiTneabilitv layer materials (if available)

5.2.1.1 Quality Control Documentat ion

Prior lo construction of a low-permeability layer tests lo confinn adequacy of low permeability materials shall be performed on specimens procured from each source area Material evaluation tests shall be performed at the CQA Laboratory The Contractor/Operator shall submit the results of source evaluation tests to the RPR The sources shall be ranked foi acceptability based on test results and transportation cost

Material shall be accepted or i ejected by tho RPR according lo results of the following tests

Moisture Content (ASTM D2216)

Particle Size (ASTM Dil40 D422)

Atterberg Lunils (ASTM D4318)

Laboratory Compaction (ASTM D1557)

Laboratory Hydraulic Conductivity (ASTM D5084)

Unless otherwise specified m project specifications or approved by the CQA Consultant these tests shall be performed at a frequency of one per every 20 000 cubic yards of low permeability material, or upon visual observation of changes m matenal type Dependmg upon uniformity of matenal the CQA Consultant shall have the authonty lo modify the frequency of testmg to address actual field conditions If identificabon of additional low permeability matenal sources becomes necessary durmg construction the same material qualification and testmg procedures shall be applied to each new souice

A test fill shall constructed lo establish a sequential and logical approach foi development of the placement and compaction piocedme to be used durmg construction lo achieve requued performance standards Samples of compacted low permeability matenal obtained fiom the fill can be tested for hydraulic conductivity to establish acceptability of the material and construction techniques The low permeability layer shall be constructed in accoraance with the project specifications

During construction of the tesl fill the CQA Consultant shall

Identify and cracks depressions or irregulanties m the subgrade that are nol filled in and compacted

1 Inspect and observe the low permeability layer test fill construction for conformity to the Contractor's approved construction methods and equipment The low permeabdity layer test fill shall be

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constructed m accordance with Uie Specifications

Visually mspect the low permeability matenal for characteristics such as gradation clod size excessive organic matenal, and other characteristics that do not meet the Specifications

Measure uncompacted lift thickness This thiclcness musl nol exceed the maximum lift thickness m the SpecificaUons

Inspect the low permeability layer lest fill for lift thickness moisture content density, uniformity, and permeability

Moisture content and relative density shall be tested al the frequency of 4 tests per lift bv method ASTM D 2922 Density shall be tested by melhod ASTM D 1556 or by the tube method al the frequency of tests per lift

Laboratory tests shall be performed as follows

One m o i s l u r e / d e n s i l y relationship test per tesl fill per soil lype by melhod ASTM D 1557

One Atterberg Limits (ASTM D 4318) per test fill

One particle size analvsis (ASTM D422) per lest fdl

One sod classification tests (ASTM D 2487) per tesl fill

One laboratory hydraulic conductivity (ASTM D 5084) per test fill

Documeni the eqmpment type and number of passes used lo oblam the specified compaction

Identify any matenal changes used m constructing the low permeabdity layer test fdl

After completion of tho tesl fdl the CQA Engineer shall

Review all test and construction results and determme the acceptability of the construction procedures m meetmg the performance goals of the specifications If necessary an additional tesl fill will be constructed and tested usmg modified construction procedures

• Observe that all cracks, depressions, and irregulanties are filled m and compacted to the specified relative compaction

• Document the approved construction procedures includmg eqmpment type number of passes eqmpment speed moisture applied and lift thickness This mformaUon shall be distributed to the Operator, CQA Consultant and Contractor for project use and reference

5.2.1.2 Subgrade Preparat ion

The Contractor/Opeiatoi shall be responsible for pieparmg the structural fdl layer lo a suitable subgrade for placement of the low permeability layer Upon completion of the structural fill layer, the CQA Consultant shall mspect the subgrade and prepare a certificate of acceptance lo be submitted to the RPR

The CQA Consultant shall be lesponsible for verifying no woik is done on lop of the structural fdl layer until acceptable for placement

5.2.2 C o n f o r m a n c e T e s t i n g

Low permeabdity materials shall be conformance tested to ensure consistency of properties of the soil quality received from bonow sources These tests are lo be performed pnor to compaction and afler completion of any necessary conditionmg of the subgrade sod Conditionmg may mclude gradation adjustments or adjustments m compaction moisture content

The followmg tests shall be conducted

Moisture Content (ASTM D2216)

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Particle Size (ASTM Dil40 D422)

Atterberg Lunils (ASTM D4318)

Laboratorv Compaction (ASTM D1557)

Laboratory Hydraulic Conductivity (ASTMD5084)

Sod ClassificaUon (ASTM D2487)

Unless otherwise specified m project specificauons, the CQA Consultant shall field screen the low permeability matenal for conformity with the particle size and soil classification specifications upon visually observable changes m the matenal type All aforementioned tests shall be performed at the CQA Laboratory at a frequency of one per every 20 000 cubic yards of low permeability material, or upon visually observable changes m the matenal type The CQA Consultant may mcrease or decrease the testmg frequency at his discretion

The CQA Consultant shall examme test results and report any nonconformance to the RPR The RPR shall accept or reject the sod based on this leview and comparison lo the pioject specificaUons

5/2 3 Cons t ruc t ion

Observation and mspection of the low permeabdity layer construction shall be coordmated with overall construction testing Acceptance cntena for construction work shall be as identified m the project specifications The CQA Consultant shall observe mspect and document the followmg during the consUuclion of the low permeability layer

Watei content and consistency of Ihe sod durmg processmg placement and compaction

• Type and level of compactive effort

RoUer type

RoUer weight

Number of passes

Action of compaction equipment on the soil surface (sheepsfool penetration pumping Clacking)

Maximum clod size

Condition of soil stockpile

Loose and compacted lift thickness

Melhod of meshmg the lifts together

Areas where damage due lo excess moisture or msufficient moisture may have occurred

5.2.4 Cons t ruc t ion Tes t ing

Construction qucdity assurance testing shall be conducted m accordance with project specifications or as directed by the CQA Consultant Field and laboratory tests shall be conducted on samples taken from the low permeability matenal dunng the course of construction work Testing and samplmg procedures shall be observed and documented by the CQA Consultant for compliance with procedures listed in Sections 5 2 4 1 and 5 2 4 2

5.2 4 1 Field Tes t ing

The CQA Consultant shall perform the followmg field tests on each lift of the compacted soil

Field Moisluie Content (ASTM D2216)

Field Densitv (ASTM D1156 D2922 D2937 D2167) use one method only

Unless otherwise specified m project specificaUons these tests shall be performed each lift at a frequency of once per every 20,000 square feet of compacted material Samplmg locations shall be selected by the CQA Consultant Dependmg upon uniformity of material the CQA Consultant shall have the authonty lo modify the frequency of testmg lo address actual field conditions

Nuclear density tesl method (ASTM D2922) shall be the prefened method of density testing The location of roulme in-place density tests shall be determmed usmg a non-biased samplmg plan

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based on slatisticalh random selecting of testing locaUons Questionable results for any single test shall be addressed by relestmg m the same genei al location Periodic (typically a mmimum of one per day) checks usmg the sand-cone method (ASTM D1556) or rubber balloon method (ASTM D2167) shall be performed to verify the nuclear tesl results

Unless otherwise noted m the project specifications, or as directed by the RPR low permeability layer perforations shall be backfilled Perforations that must be baclddled shall mclude but are not limited lo the followmg

• Nuclear density test probe locations

• Sand-cone test locations

F-vdraulic locations

conductivity samplmg

Perforations shall be backfilled with a soil-bentonite or concrete slurry mixture and be compacted with a tampmg rod modified oi standard Proctor hammer or a hand tamper Al a mmimum the CQA Considtant shall perform roulme tests and observations on the backfdled

An mcreased frequency of testing shall be used upon recommendaUon from the CQA Consultant and approval from the RPR if one or more of the followmg conditions develop durmg construction

Rollers slip duimg operation

Lift thickness is gieatei than specified

Low permeability matenal has an improper and/or vaiiable moisluie content

• Fewer than the specified number of roller passes are made

Dirt-clogged rollers are used to compact the matenal

The degree of compaction of the material is suspect

Additional testing may also be consideied bv tlio CQA Consultant and RPR when

Weather conditions aie adverse

• Roller have not used optimum ballast

Equipment breaks down frequently

Grading is bemg started or fmished

5.2.4.2 Laboratory Testing

The followmg tests shall be performed bv the CQA Laboratory to confirm adequacy of the material and placement of the compacted fdl

Atterberg Lmiits (ASTM 4318)

Hydraulic Conductivity (ASTM D5084)

The Atterberg limits and the hydraulic conductivity of the compacted soil shall be determined on undisturbed samples obtamed from the constructed low permeabdity layer at a frequency of one tesl per 50,000 cubic yards of placed material Acceplabdity criteria shall be as identified m project specifications Laboratory hydraulic conductivity samples shall be taken such that the sample tube is mserted mto the low permeabdity layer perpendicular to the plane of the constructed surface The lube hall be mserted into the lift by applymg a gradually mcreasmg pressure

5.2.5 Defects and Repairs

Al locations where testing mdicates that lequuemenls of the project specifications are nol met the CQA Consultant shall determme the extent and the nalme of the defect and lecommend conecUve actions lo the RPR In addition if the low permeabdity layei has been subject to adverse weather conditions followmg inspection, the CQA Consultant may reexamme the soil for possible damage

Afler determmmg the extent and nature of a defect the CQA Consultant shall promptly notify the Contractor/Operator and the RJPR As needed a meetmg mvolvmg the Contractor/Operator, CQA Consultant RPR and other appropriate parties should be held lo assess the problem review

niiMPrn/Hi AniQB/lrl Hardina Lawson Associates 13

Sunrise Mountain Landfill Construction Quality Assurance Plan

1

1 4

alternative solutions and implement a response plan

The Contractor/Operator shall lepair all deficiencies to meet project specifications If a project specification criterion caimol be met because of imusual weather or other conditions the CQA Consultant or Design Engmeer shall develop and present the RPR possible solutions for approval

The CQA Consultant shall relesl any deficient area followmg repair of the reported defect All retests by the CQA Consultant shall verify the defect has been corrected before additional work IS perfonned by the Contractor/Operator m the area of the deficiency Fmally, the CQA Consultant shall observe any repair and report any noncompliance with the above requirements m wntmg to the RPR

5.2.6 P o s t - c o n s t r u c t i o n

The CQA Consultant shall conduct a post-construction inspection upon completion of the low permeability layer The purpose of this inspection shall be to identify areas that might require corrective action by the Contractor/Operator Inspection shall occur prior to placement of any matenal on top of the low permeabihty matenal The CQA Consultant shall inspect the low permeability layer for the followmg

Areas damaged or improperly compacted

• Areas excessively eroded by lamfall or other means durmg the construction period or as a result of construction acUvities

Large irregularities or protrusions in the low permeabdity fill layer grade resulting from grade stakes, cracks, and excess matenal placement

In addition the CQA Consultant shall arrange for and review results of a construction record survey, to venfy the low penneability layer has been placed lo withm acceptable tolerances of design grades and slopes

5.3 Eros ion Layer

Erosion layer material generally consists of medium textured soils which are woll-graded The purpose of the erosion layer is to protect the low permeabdity layer fiom weather or other damage

5.3.1 P re -Cons t ruc t ion

Pre-construction activities of the CQA Consultant shall mclude the followmg

• Review erosion layer design plans and specificaUons

• Review Contractor's/Operator's work schedule

• Review construcbon melhods and equipment lo be used for placement of the erosion layer

Pnor lo construction of the erosion layer particle-size distnbution of sod from each source shall be determmed once for every 40,000 cubic yards by the CQA Consultant Testmg shall be performed by the CQA Laboratory, and the matenal shall meel the project specifications Dependmg upon uniformity of matenal, the CQA Consultant shall have the authonty lo modify the frequency of testmg to address actual field conditions

Additionally, the erosion potential of the lopsod shall be evaluated The erosion potential shall not exceed 2 tons per acre per year as calculated by the US Department of Agricultures Universal Soil Loss Equation (USLE)

5.3.2 Cons t ruc t ion

The erosion layer shall be compacted moderately and uniformly to the specified thickness The firmness of the compacted erosion layer may and should be mdicated m project specifications The CQA Consultant shall

Verify actual thickness of the erosion layer after compaction by direct measurements Fmal grades should be verified by a construction record survey

DUMPCOlHLAOlSZlkd Harding Lawson Associates 14

Sunrise Mountain Landfil l Construct ion Quality Assurance Plan

performed by a qualified land suri.e%oi and observed bv the CQA Consultant

• Ensure the specified particle-size distnbuUon mmimizes dust and erosion

Upon completion of the erosion layer, the CQA Consultant shall prepare a certificate of acceptance for the erosion layer and submit it to the RPR The CQA Consultant shall report any nonconformance of this layer with specified requirements to the RPR

5.3.3 De fec ts a n d Repa i r s

Acceptability cntena for testmg shall be as identified m the project specifications If the erosion layer has been subject to adverse weather conditions followmg mspection the CQA Consultant shall reexamme the sod for possible damage

After determmmg the extent and nature of a defect the CQA Consultant shall promptly notify the Contractor/Operator and the RPR As needed, a meetmg mvolvmg the Contractor/Operator, CQA Consultant RPR and other appropriate parties should be held to assess the pioblem levfiew alternative soluUons and implement a lesponse plan

The Contractor/Operator shall repair all deficiencies lo meet project specifications Lf a project specificaUon criterion carmot be met because of unusual weather or other conditions, the CQA Consultant or Engmeer shall develop and present the RPR possible solutions for his approval

5.3.4 Post-Construction

A post-construction inspection shall be conducted by the CQA Consultant upon completion of the erosion layer This inspection will identify those areas that might require corrective action by the Contractor/Operator The CQA Consultant shall inspect the erosion layer for the followmg

• Low spots or depressions which would cause water lo pond on the landfdl

Areas damaged or improperly compacted

Areas excessively eroded bv lamfall or other means during the constmction period or as a result of the consUiiclion activities

« Large megulanties or protrusions resultmg from rocks, sticks grade stakes cracks, and excess material placement

In addition, the CQA Consultant shall arrange for and review results of a construction record survey lo venfy the erosion layer has been placed lo withm acceptable tolerances of design grades and slopes

DUMPCO/HLA0198Ad Hardmg Lawson Associates 1 5

J

1 I

DISTRIBUTION

Sunrise Mountain Landfill Construcbon Quaht} Assurance Plan Disposal Urban Mamtenance Processmg Company, Inc Clark County, Nevada

Aprd 14 1994

Copies 1 - 3 Disposal Urban Mamtenance Processmg Company Inc 770 East Sahara Avenue Las Vegas, Nevada 89104

Attention Mr George Rogers

Copies 4 - 5 Clark County Department of Public Woiks 6655 West Sahara Avenue Buddmg C-2 04 Las Vegas Nevada 89102

Attention Mr M ] Mannmg

Copies 6 -7 U S Department of the Intenor Bureau of Land Management 4765 Vegas Dnve Las Vegas, Nevada 89126

Attention Mr Gary Ryan

Copy 8 Clark County Health Distiict 625 Shadow Lane Las Vegas Nevada 89127

AltenUon Mr Victor B Skarr

Copy 9 Job File

Quality Control Reviewer

W Cliff Yeckes.PG Managmg Prmcipal Nevada Environmental Manager #EM-1014

EHMAVCY/kcl


Attachment B

Notes and Observations by Brent Lewis, BLM on October 2,1997 Site Visit to the Sunrise Mountain LandHil


Brent's notes forwarded Date 10/21/1997 09 43 am (Tuesday) From Brent Lewis To ilmnvc50 ilmnvd50 mmoran, ilmnvc91 ilmnvd91 sskinner

Subject Sunrise Mountain Landfill

This letter documents my observations ofthe Sunrise Mountain Landfill dunng a visit on Oct 1-2, 1997 The objectives of this visit were to onentate several individuals who may be working on the different aspects of the landfill evaluation and to examine the depths of fractunng we observed in the cap last spring Numerous fractures were observed in the cap last spnng, but subsequent re-grooming of the landfill has covered their surface expression This is not to say the fractures no longer exist, but have only been filled but unconsolidated matenal As we observed in the field on October I and 2, the fractures are reopening

On Oct 2, 1997 we used a backhoe to excavate several fractures as well as several areas not fractured The results were surpnsing It appears fractunng only occurs where the cap was constructed with the required compacted/engineered clay interval Moreover, the fractures pienetrated the entire thickness of the clay interval Such depths compromise Its purpose of preventing infiltiation In the areas where no fractunng was observed, the landfill's surface appears to be settling This settling is expected and likely causes the fractunng as the clay interval provides an ability to hold open movements caused by the settling As a result of the settling, low lying topographic depressions are developing These areas are ponding water and allowing undesirable infiltration as moisture was found at completion depths of several excavations

Generally speaking, based upon the topographic expressions of the landfill's surface the extent of capping does not conespond to the extent depicted in the approved closure plan hi fact. It IS possible the majonty of the landfill has only a cover which is allowing a direct contact exposure pathway, infiltration and a dispersed off-gasing of landfill vapor

A photo-ionizmg detector (PED) and an explosimeter were used for health and safety momtonng dunng the excavations Although the weather was very windy, a severe odor was encountered at depths below the clay interval, no instrument readings above background were encountered in the breathing zone However, PED readings were encountered in several pits, see attached field notes

Vapor measurements from a vent located on the east face of the landfill provided the greatest concentrations recorded by the field instruments, 502 ppm on the PED and 25% LEL on the explosimeter These reading strongly suggests further evaluations of the vapor are needed As planned the PBD was not capable of detecting methane or hydrogen sulfide and the explosimeter would indirectly provide methane concentrations Consequently, the PID readings are of an organic vapor(s) of unknown composition

"12


Based upon our current knowledge of the site the following recommendation are made

1 In order to comply with current Nevada regulations a detailed vapor analysis survey is required to quantify the non-methane component of the vapor

2 An on-going maintenance program of the cap should be initiated to ensure proper runoff and run-off contiol which prohibits infiltration and exposure

3 Ground water momtonng wells should be installed and monitored according to a program capable ot addressing both spatial and temporal aspects of the site

More of Brent's notes Date 10/21/1997 10 23 am (Tuesday) From Brent Lewis To ilmnvc50 ilmnvd50 mmoran, ilmnvc91 ilmnvd91 sskinner

Subject field notes

Attached are my field notes I was pnmanly concerned with the instrumentation reading and providing Steve Dwyer with the depth measurements, therefore, my depths measurements are only approx Field notes by Brent Lewis of the Sunnse landfill cap evaluation (Oct 2 1997)

Pit#l Located on the nonh side of the uppermost lift

Background PID= 0 4 Explosimeter = 21%

All of the following readings were taken from the bottom of the excavation pit Readings from the breathing zone are noted only if they exceed background levels

1st backhoe scoop approx 8" depth PID= 0 5 Explosimeter = 21%

2nd backhoe scoop approx I 3 ft depth PID= 0 5 Explosimeter = 21%

3rd backhoe scoop approx 2 ft Depth PID= 0 5 Explosimeter = 20 9%

4th backhoe scoop approx 2 5 ft depth PID= 0 5 Explosimeter = 20 9%

5 th backhoe scoop approx 2 7 ft depth PID = 04 Explosimeter = 20 8% Black matenal encountered no direct readings

above background A two inch wide fracture reaches depths greater than the bottom ofthe clay interval

^1


Pit #2 Located northern edge of upper landfill lift, but west of pit #1 on the lower level Weather has become hot and very windy and causing some dnft in instruments detected background


Background PID= 4 0 Explosimeter = 21%

1st backhoe scoop approx 8" depth PID= 4 0 Explosimeter = 21%

2nd backhoe scoop approx I 3 ft depth PID= 5 2 Explosimeter = 21 % Black material encountered

3rd backhoe scoop approx 2 ft depth PID= 10 2 Explosimeter = 20 9% Oxygen, 2% Lower explosive limit (LEL)

FractureTl to the depth of the waste 1 5 ft Moisture is also obvious to this depth

Pit #3 Located southwest of pit #2 and near several small bushes growing in the cap No fractures at the surface Area is located in a slight depression


Background P1D= 4 0 Explosimeter = 21%

1st backhoe scoop approx 8" depth PID= 7 0 Explosimeter =21%

2nd backhoe scoop approx 1 3 ft depth PID= 7 0 Explosimeter = 21% , 2% LEL Black matenal encountered

3rd backhoe scoop Approx 2 ft depth PID= 7 0 Explosimeter = 21%, 2% LEL Black material encountered

Pit #4 Located northeast of pit #3 and near several small tamarisk bushes growing in the cap No fractures at the surface Area is located in a slight depression with a yellow surface hue



Background PID= 4 6 Explosimeter =21%

I St backhoe scoop approx 8" depth Black matenal encountered PID= 7 0 Explosimeter = 21%

2nd backhoe scoop Approx 1 3 ft depth PID= 11 8 Explosimeter = 21% , 2% LEL Black and light gray matenal encountered Slight petioleum odor

Vent readings A single vent was monitored This vent is located on the west face of the landfill just below the upper lift The instruments were placed in a small vent opening

PID = 502 ppm Explosimeter = 25% LEL

^5

Sunnse iMountain Landfill Final Cover Evaluation

Attachment C

Excavation Procedure drafted by BLM for October 2,1997

site visit to the Sunrise Mountam Landfill

^6


The following is an addendum to the Sunnse Mountain workplan This addendum is necessary because the use of backhoe excavations were not previously addressed

Purpose

Previous observations of the landfill cap have found an abundance of surface fractures On the ground's surface these fractures are as much as 0 5 feet in width and over 50 feet in length The cause of the cracking is unknown at this point in time Because the functional purpose of the cap may be in jeopardy, the depths of the fractures must be determined

Objective

The objective of this effort is to determine if the depths of surface fractures are greater than that of the engineered clay interval of the landfill cap

Methodologv A backhoe will be used to excavate through fractures at several locations on the landfill Excavations should be perpendicular to the fracture inorder to limit the amount of sediment forced into the fractures by the backhoe The excavation depths will be no greater than one or two feet past the engineered clay interval, if fractures are observed to be deeper Conversely, if fracturing terminates at the top of the clay interval the excavations will not precede any further The backhoe will be used for easy access to the required depths while hand excavation will be necessary to investigate fractured surfaces and clay material of each excavation pit Exposed profiles of each excavation pit will be photographed and the following information from each excavation is to be recorded

1 Depth/thickness of rubble cover and matenal encountered 2 Depth to top of the engineered clay layer and matenal encountered 3 Width of fracture at surface and at every six inch interval of the depth of the

excavation depth 4 Depth to bottom of the clay interval, matenal encountered and visual conditions of the

clay interval 5 If the excavation is required to go through the clay layer the type of matenal

encountered beneath the layer is to be recorded as well as the width of the fractures 6 Each excavation will precede by segregating and placing all excavated material on

visqueen After recording the above information (items 1-5) each excavation will be backfilled with the same material and compacted to specifications previously approved in the landfill closure plan If mixing of the excavating material prohibits Its use for the reconstruction of the clay layer, new material from the cap stock pile will be used Construction of the clay interval will meet the thickness and compaction cntena of the closure plan

^7

Sunnse Mountam Landfill Final Cover Evaluation

Attachment D

Qualifications of Stephen F. Dwyer

^8


Qualifications of Stephen F. Dwyer

EDUCATION

M.SyCivil Engineering, University of New Mexico, Albuquerque, N M

B-S7Civil Engineering; New Mexico State University, Las Cruces, N M

Master of Business Administration; New Mexico State University, Las Cruces, N M

EMPLOYMENT HIGHLIGHTS

Expenence consists of over 15 years of engineenng in the areas of design, construction management, and research and development Cunently working as the Pnncipal Investigator tor the Alternative Landfill Cover Demonstration (ALCD) The ALCD is a research project funded by the Department of Energy that demonstrates altemative landfill cover components and systems to provide long-term containment of waste in and and semi-and environments Data from the project includes construction information about the construction of six different landfill cover designs and their associated construction costs, and water balance data including percolation, soil moisture changes, runoff, lateral drainage, and evapotranspiration Other cunent projects include serving as a technical consultant to EPA Region 8 for the implementation of a final cover over a hazardous waste landfill in Cheyenne, Wyoming, wnting the design guidance for RCRA/CERCLA final closures for the EPA, designing a final cover for a Mixed Waste Landfill at Sandia National Laboratories in Albuquerque, NM

PROFESSIONAL SOCIETIES AND HONORS

Registered Professional Engineer- States of New Mexico, Colorado and Ohio Member -American Society of Civil Engineers Graduated No 1 - M B A Program, Dean's List, Chi Epsilon, Academic All-Missoun Valley Conference (Basketball @ New Mexico State University), Sandia Award for Excellence, Sandia Employee Recognition Award, New Mexico Society of Professional Engineers Engineenng Achievement Award

^9


Attachment E

Memos and Fact Sheets Relating to Municipal Solid Waste Emission Guidelines

40

NOV-ll-sr 2106 702 647 5010 P 02 R-SiB Job-731

i l / 1 2 / 9 7 08 03 F U 702 647 5010 !2l002

MEMORANDUM

TO Elizabeth Gilmartin, NSR Supen/isor, APCD

FROM Ben Griffith. Permit Specialist, APCD

RE Sunnse Lanfill and Subpart Cc

DATE Febnjary 13. 1997

y d /y-y/yy

T/ A/vKr Attached to this memo is a copy of 40 CFR 60 Subpart Cc - Emission Guidelines and Compliance Times for Municipal Solid Waste Landfills. Subpart Cc requires states to develop an Emission Guideline for Municipal Solid Waste (MSW) landfills which meet the cntena defined in 40 CFR 60 33c (a) I believe that the Emission Guideline would be applicable to the dosed Sunrise landfill because (1) waste was accepted after November 8, 1987. (2) I think the design capacity was greater than 2.5 million megagrams or 2 5 million cubic meters, and (3) I think non-methane organic compound (NMOC) emission rate is greater than 50 megagrams per year

To detenmine for certain that Subpart Cc is applicable, we would have to obtain data on the amount of waste placed in the landfill and the time of placement If the amount of waste exceeds the 2 5 million megagrams, an initial estimate of the NMOC emission rate would be calculated from the equation provided in 40 CFR 60 754 (a)(1)(i). If the calculated NMOC emission rate is greater than 50 megagrams per year, control devices meeting the requirements of 40 CFR 60 33c(c) would have to be installed unless a site-specific NMOC emission rate less than 50 megagrams per year is determined by Tier 2 or Tier 3 methods outlined in 40 CFR 60 754

Subpart Cc requires the control devices specified in 40 CFR 60 33c(c) to be installed within 30 months after the effective date of a state emission standard. Subpart Cc was promulgated on March 12, 1996 40 CFR 60.23(a) requires the state to submit a plan within 9 months of the promulgation date To my knowledge, no such plan has been submitted and the deadline of December 12, 1996 has passed 40 CFR 60 27(d) requires the administrator to promulgate a pian within 6 months of the due date if the state fails to submit a plan If this course is followed, the state guideline would be effective June 12. 1997.

Based on the aforementioned timelines and assumptions, control devices meeting the requirements of 40 CFR 60 33c(c) would be required to be installed at the Sunnse landfill by December 12. 1999 /Q/y

NOV-n-97 21 06 702 W 5010 P 03 " " ^ ' ^ Job-731

. x /12 /97 08 03 ¥ \ 1 702 647 5010 ' ^ " ^ ' ^

C L A R K C O U N T Y H E A L T H D I S T R I C T

PO BOX 4426 - 625 SHADOW LANE - LAS VEGAS NEVADA 83 127 702-383-1275 FAX 702 -383 14^

Distribution List .- , - ^

Allen Bell - Mequite Public Works ^ ^ ^ o\ -' -/' O James Carlson - Nevada Power Company ^ .q^ -] Mark Chatterton - Bureau of Land Management ^y"^^ ^ Joe Cyphers - Nevada State Parks ,,c ^ 1 - ^ 5 G £ Conrad Dziewulski - Nellis AFB ^,^-{'X 3" ^^,j5],vi3 Davd Emme - Nevada Division of Envtronmental Protection y^^s '*'' - ^* Col Michael F Fukey - Nellis AFB Karl Gieszi - So Cal Edison Co Elizabeth Gilmartin - Clark County Health Distnct Alan Gove - Boulder City Public Works Matt Haber - U S Environmentai Protection Agency Tom Isola - Silver State Disposal Service Donald Kwalick - Clark County Health District Teresa Mann - Boulder City Disposal Marty Manning - Clark County Public Works Michael Moran - Bureau of Land Management Michael Naylor - Clark County Health Distnct Roy E On- - Nevada State Parks Dr Otto Ravenholt - Clark County Health District Greg Sanks - Nevada Power Company Victor Skaar - Clark County Health Distnct Clare Schmutz - Clark County Health Distnct Dick Serdoz - Nevada Divsion of Environmentai Protection Dave Sorg - James Hardie Gypsum Susan Stewart - Titanium Metals Company Mike Sword - Clark County Health Distnct Joe Titus - Henderson Public Works Guy Wells - Wells Cargo. Inc Edmund Wojcik - Clark County Health Distnct

C ^RK COUNTY . LAS VEGAS . NORTH LAS VEGAS - BOULDER CITY HENDERSOt

NOV-11-9? 21 06 702 647 5010 P 0* "-918 Job-731

. 1 / 1 2 / 9 7 08 04 FAX 702 647 5010 121004

/

C L A R K C O U N T Y H E A L T H D I S T R I C T

PO. BOX 4426 - 625 S H A D O W LANE LAS VEGAS NEVADA 89 1 27 702-383-1 276 . FAX 702-3B3-1 44.

TO Distnbution List

FROM Ben Griffith, Permit Specialist, Clark County Health District - Air Pollution

Control Division

RE Municipal Solid Waste Landfills

DATE June 11, 1997 Landfills in Clark County have not previously been permitted by Air Pollution Control However, on March 12. 1996 (Federal Register 61 FR 9918), the Environmental Protection Agency (EPA) promulgated a New Source Performance Standard for Municipal Solid Waste (MSW) Landfills (40 CFR 60 Subpart WWW) and an Emission Guideline and Compliance Time for MSW Landfills (40 CFR 60 Subpart Cc) The federal regulations were incorporated by reference into the Air Pollution Control Regulations ofthe Distnct Board of Health of Clark County on January 23. 1997

The following definitions apply

The term Municipal Solid Waste (MSW) landfill means an entire disposal facility in a contiguous geographical space where household waste is placed in or on land An MSW landfill may also receive other types of RCRA Subtitle D wastes such as commeraal solid waste, non-hazardous sludge, conditionally exempt small quantity generator waste, and industnal solid waste Portions of an MSW landUll may be separated by access roads An MSW landfill may be publicly or privately owned An MSW landfill may be a new MSW tandWl, and existing MSW landfill, or a lateral expansion

Household waste means any solid waste (including garbage, trash, and sanitary waste in septic tanks) denved from households (including, but not limited to, single and multiple residences, hotels and motels, bunkhouses, ranger stations, crew quarters, campgrounds, picnic grounds, and day-use recreation areas).

Solid waste means any garbage, sludge from a wastewater treatment plant, water supply treatment plant, or air pollution control facility and other discarded matenal, including solid, liquid, semisolid, or contained gaseous matenal resulting from industnal, commercial, mining, and agnculturat operations, and from community activities, but does not include solid or dissolved matenal in domestic sewage, or solid or dissolved matenals in imgation return flows or industnal discharges that are point sources subject to permits under 33 U S C 1342, or source, speaal nuclear, or by-product matenal as defined by the Atomic Energy Act of 1954, as amended (42U SC 2011 et seq)

I RK COUNTY - LAS VEGAS - NORTH LAS VEGAS - BOULDER CITY . HENDERSON

NOV-11-97 21 06 702 547 5010

. 1 / 1 2 / 9 7 08 04 FAX 702 647 5010

P 05 R-918 Job-731 I2100S

y

Non-degradable waste means any waste that does not decompose through chemical breakdown or microbiological activity Examples are, but are not limited to, concrete, municipal waste combustor ash, and metals

The Emission Guideline is applicable to the faalihes which meet the following four cntena

1 Each exishng MSW landfill for which construction, reconstruction or modification was commenced before May 30,1991

2 The landfill has accepted waste at any time smca November 8, 1987, or has additional design capacity available for future waste deposition

3 The landfill has a design capaaty greater than or equal to 2 5 million megagrams (2 76 million tons) or 2 5 million cubic meters (3 27 million cubic yards) The landfill may calculate design capaaty in either megagrams or cubic meters for companson with the exemption values Any density conversions shall be documented

4 The landfill has a Nonmethane Organic Compound (NMOC) emission rate of 50 megagrams (55 1 tons) per year or more

If you have an MSW landfill that meets the first three cntena, the method to calculate the NMOC emission rate (Tier I screening) is available in the regulations cited above Alternatively I have a computer model which will calculate the NMOC emission rate (Tier I screening) if you provide the solid waste acceptance rate on an annual average or year to year basis from opening to closure

If the above four cntena are exceeded based on the Tier I screening method There are Tier II and Tier III methods which require actual testing at the landfill site to determine the NMOC emission rate If the NMOC emission rate is above 50 megagrams per year, a control system is required to t>e installed within thirty months of the date the Emission Guideline was enacted, i e by July 23, 1999

Pease submit the following following infonmation for our records, regardless of the applicability ofthe new regulations I will preform a Tier I screening analysis on any that meet the first three cntena to determine whether the NMOC emission rate exceedes 50 megagrams per year

1 2 3 4 5

Name of Facility Location of Faa I ity Contact Person (Phone Number) Start Date Closure Date

NOV-n-57 2106 702 647 5010 ? 05 R-91B Job-731

1 / 1 2 / 9 7 OS 04 FAX 702 647 5010 12)006

6 Design Capaaty 7 Total amount of solid waste in place 8 Year to year solid waste acceptance rate (or)

averaged solid waste acceptance over penods from opening to closure 9 Percentage of waste that was manerated (legally or illegally) 10 Percentage of non-degradable waste in place

Please answer all questions as completely as possible Code each answer as R-record. M-measurement. E-estimate. or G-guess

The New Source Performance Standard. 40 CFR 60 Subpart WWW, has the same cntena regarding size, and control technology requirements as the emissions guideline, but It IS applicable to each municipal solid waste landfill that commenced construction, reconstruction or modification or began accepting waste on or after May 30. 1991 Physical or operational changes made to an existing MSW landfill solely to comply with the emissions guideline (Subpart Cc) of are not considered construction, reconstruction, or modification for the purposes of Subpart WV\AA/

Please contact me if you think your landfill is subject to Subpart WWW

All active landfills of any type, regardless of applicability of the aforementioned regulations, would probably require an air pollution control pennit on the basis of Particulate Matter (PMio) emissions

if you have any questions or comments, please contact me at 702-383-1276, Fax 702-383-1443

Sincerely,

CLARK COUNTY HEALTH DISTRICT

Ben L Griffith Permit Specialist 11 Air Pollution Conf ol Division

NOV-11-97 04 00 1 702 5475023 P 02 R-909 Job-722

^ l l / i l / 9 7 _ TIE 13_58 F U _ 1 702^6475023 BUREAU OF L\ND MGT 121002

\Pf r -m7(Tl iEl 15 19 NV DIV ENV PROT TEL 7028850868 P 001

3/1/96

FACT SHEET

FINAL AIR REGULATIONS FOR MUNICIPAL SOLID WASTE LANDFILLS

TODAY'S ACTION

• Under authonty of the Clean Air Act. the Environmenial Protection Agency (HPA) today issued a final regulation contiollmg emissions of a variety of air pollutants fi-om new and existing large municipal solid waste landfills Landfills subject to EPA s regulauon accept and handle everyday household waste, they do not handle hazardous waste Currently, 60 percent of municipal solid waste generated m the United States is landfillcd 16 percent is incinerated, and 24 percent is recycled

• E P A worked m pannership with major stakeholders, includmg private industry, the National Association of Counties, the National League of Cities, and the Solid Waste Association of North Amcnca to develop the fmal rule

WHAT ARE THE HEALTH AND E N V I R O N M E X N T A L BENEFITS' '

• As the waste m a landfill decomposes, it breaks down to form landfill gases such as methane, smog-causmg volatile organic compounds (VOCs), and air toxics, pollutants known or suspected of causmg cancer and other senous health effects Landfills are the largest anthropogeruc source of methane emissions in the United States Methane is a potent greenhouse gas that contnbutes lo global warming

• EPA's final air rules for municipal solid waste landfills will achieve si^ificant reducnons in emissions of VOCs and air toxics, such as benzene, carbon tctrachionde and chloroform EPA's regulation will reduce emissions of VOCs, air toxics, and malodorous compounds from existing and new landfills by over 90 000 tons annually (a 53 percent reduction from current levels) This rulemakmg will also result in sigiuficant reductions in emissions of methane, a major constituent of landfill gas and a potent greenhouse gas By reducing methane emissions. EPA's regulaaon wjH also increase safety in and near landfills

' *° ' ' ' ^ '^^ " ' '"' ' 712 B475023 P 03 R-m Job 722 . 1 /11 /9 , TUE 13 58 FU 1 702 6475023 BUREAU OF L ND MGT 2)003

//{TUEl 15 20 NV DIV ENV PROT TEL 7028850868 P 002

HOW DOES TODAY'S ACTION RELATE TO THE U.S CLIMATE CHANCE ACTION PLAN-^

• Landfills arc the largest anthropogeruc source of methane emissions in the United States, constituting about 40 percent Methane reductions of over 50 percent in the year 2000, anticipated under this rulemaking, as well as reductions achieved by EPA's Landfill Methane Outreach Program, arc important components of the U S "Climate Change Action Plan" to reduce emissions of greenhouse gases to 1990 levels by the year 2000 The rule alone will reduce greenhouse gas emissions by 37 1 million metnc tons of carbon equivalent (6 2 million tons of methane) When Ihe outreach program is included as well total reductions will be 38 6 mmtce (6 8 rmlhon ions of methane)

• This rulemaking and the EPA Landfill Methane Outreach Program (LMOP) go hand-m-hand lo provide bubsiantial reductions in greenhouse gas emissions Tlie new regulations will cause many landfills acro;»s ihe countiy to asseivS llieir landfill gas emissions and the potential tor cost-effective recovery of energy trom this gas The LMOP Will provide ihese landfills wjih guidance on how to comply wuh the regulations, including how lo evaluate energy recovery options Working together these two cornerstone actions of the Climate Change Action Plan will encourage many landfills co capture and use their landfill gas

WHAT ARE THE MAIN COMPONENTS OF EPA'S FINAL RULE?

• EPA's final rule takes tlic form of new source performance standards ior new l<indfills and emission guidelines for existing landfills Slates will adopt and entorcc the emission guidelines for existing landfills The regulation will require large landfills tliat emit landfill gas in excess of 50 megagrams (Mg) per year to control emissions In general, conlrolhng emissions involves drilling collection wells into the landfill and routing the gas to a suitable energy recovery system or combustion device Specifically the regulations will require the following

• New and cxisung landfills designed to hold 2 5 million Mg of waste or more will be required lo install gas collection systems or prove that the landfill emits less than 50 Mg per year of non-methane organic compounds mcluding smog-causmg VOCs and air toxics

• EPA s final rule provides the owner or operator of a landfill with a tier system lor determimng if controls will be required If the owner or operator iniiiallv calculates the emissions to be above the 50 Mg per year threshold by using default parameters provided m the regulation, the tier system provides the opportunity to conduct sampling and deiemiine site specific values to prove that emissions are below the emission tlireshold and thai controls are not required

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• If emissions controls arc required, the rule provides fiexibility lo industry by allowing landfill owners or operators to design their own gas collection and control system to fit their unique circumstances A control device may be a flare or a device which utilizes the energy content of the gas, such as an internal combustion engine, a turbine, or a boiler

• EPA's final rule contains an operational standard that requires a landfill's surface methane concentiation to be monitored on a quarterly basis If the surface concentration of methane is greater than 500 parts per million after three consecutive measurements, the regulation requires system expansion to accommodate the excess gas This reduces the chance of explosions in or near a landfill

• The fmal rale will achieve substantial emission reductions without placing an undue financial burden on mumcipahtics and will place no burden on small municipalities (since small landfills are exempted from the regulation) Waste disposal costs will increase only about 20 to 40 cents per household EPA anticipates that many landfills will use energy recovery systems further reducmg costs per hoLisehold

WHO WTLL BE AFFECTED BY EPA'S FINAL R U L E '

• Approximately 7000 landfills exist in the Unired States However, over 90 percent of these landfills have design capacities less than the 2 5 million Mg exemption in the regulation Thus only about 4 percent of the existing landfills nationwide will be subject to the regulation Of the 900 new landfills estimated to open dunng ihe next five years, approximately 5 percent will be subject to the regulation

FOR FURTHER INFORMATION

• Anyone with a computer and a modem can download the final rule from the Clean Air Act Amendments bulletin board (look under "Recently Signed Rules") on EPA's clectromc Teclinology Transfer Network (TTN) by calling (919) 541-5742 For further mformanon about how to access the board, call (919) 541-5384 For teclmical qae,«!nons about the rule contact Martha Smith of EPA's Office ot Air Quality Planning and Standards at (919) 541-2421 For mformation on the EPA Landfill Methane Outreach Program (LMOP), call the LMOP Hotline at (202) 233-9042

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F e d e r a l Regis ter / Vol 01 No 4>i / T u e s d a y M a r c h iZ 1096 / Rules a n d R t ' g u h l i o n s 9 9 1 ' J

§60 16 Priority IISL • ^ « • *

OlhiT '5otirrf Cfllcijoni s * * * * *

MuniLUMl bdlid wibtL landfills -' * * * * *

7 Si Ltioii 60 10 IS imi ndi d bv id(iin>; 1 now paragriph (r)ô read ib lol lows

§60 30 Scope

ic) bubpart Cc—Miuii<,ipai bolid W istp Lai dfilU

8 Pan trO IS furtlier aijiendi,d by adding the Subpart Ci. 'o road a^ follow s

Subpart Cc—Emission Guidelines and Compliance Times for Municipal Solid Waste Landfil ls

Sttc 60 10c Scooe 60 31i, Detinjtions GO J2c Oestunatt-d faciliue^ 60 33c Emission guidelines for nunic pai

solid uas[u laiidlill eTissions hO 3-11. T<,sl Tiethods and procLdures GO 35c Rtporting and recorci-ettpirg

guidelines 60 36c Compliance times

S u b p a r t C c — E m i s s i o n G u i d e l i n e s and C o m p l i a n c e T i m e s fo r M u n i c i p a l So l i d Was te L a n d f i l l s

§ 60 30c Scope

This subpart corikairs emission guideunes and compliance t m e s for the control of certain designated oollulants from certain designated m u i i c i p a l solid waste landfiUs in accordance vuh section 111(d) of the ^ct a n c suooart B

§60 31c Oednitions

Terms used but not defined in this subpart have the meaning given them in the Act and in subparts A B ana VVVWV of th.s part

\durucipal solid waste landjill or MSW landfill means an entire disposal laciiitv in a contiguous geographical space where housenold was e is placed m or on land An MSW landfill may also receive other tvoes of RCRA Subutie D wastes such as comnerc i a l solid waste, nonhazardous sludge t onditionallv exempt small quanti ty generator waste, and m d u s t n a l solid waste Poruons of an MSW iandni l may be separated by access roads An MSW landfill may oe puohcly or pnvate iv owned An MSW landfill -nay be a new MSW landfill an existing MSW landfill or a lateral expansion

•• \nt prioruiied >inco an NSPS for rhii mj|Or SOUTH, atcyury h.15 tlrenuy bwii p nmultjjaij

§ 60 3Zc Designated racllltles

(a) Th( designated facilitv to wlui h ihr i»uidcli IDS apply IS each uxisting MSW landfill tor which conslniclinii n»coiistruction or inodiricalion was coiumuiiced bofon' M iv JO 14<)1

HI) Physu T1 (ir (ipi-ralional c^Miigt s iinilt' to an i-Msting MSW landfill soW'ly to cciniply Willi an cmissKm giiidcluio iru nut considered a modification or rcf onstruction and would not subject an exuiing MSW landfill lo the ri qtiirumi iits ot subp irt WWW [sco V O ' ^ ' O o f S u b p i r t WWW]

^ 60 33c Emission guidelines lor municipal solid waste landfill emissions

(a) for approval a State plan shall include control of MSW landfill emissions at each MSW landfill meeting the tollowing three condit ions

(1) The landfill has accepted waste at any tune since November 8 1987 or has additional design capacity available for "jture waste deoosition

(2) The landfill has a design capacity greater than or equal to 2 5 million megagrams or 2 5 million cubic meters The landfill m w calculate design capacity in either ^negagratns or cuoic meters for comparison with the eAemption values Any density conversions shall be documented and submitted with the report and

(3) The landfill has a nonmethane organic compound emission rate of 50 megagrams per year or tôre

(b) For approval, a State plan shall include the installation of a collection and control system meeting die conditions orovided in §60 752fb)(2)(ii) 01 this part at each MSW lanali l l meeting the conditions in paragraph (a) of this section The State pian shall include a process for State review and approval of the site soecific design olans for the gas collecUon and control svste'n{s)

(c) For approval a Siate plan shall include nrovisions for the control of collected MSW landfill emissions through the use of control devices 'neet^ng the requirements of paragraph (c)(1) (2) or i3) of this section except as provided m § 60 24

(1) An open flare designed and operated in accordance with the parameters established in § 50 18 or

(2) A control system designed and operated to reduce NMOC bv 98 weight percent or

(3) An enclosed combustor dfsignet! and operated to reduc(> the outlet NMOC concentration to 20 parts per mill ion as hexane by volume dry basis at 3 percent oxygen or less

§ 60 34c Test methods and procedures

For jporoval a State olan shall include orovibions for the calculation

of till landfill NMOC omission rate lisled in ^ bO 7'">4 as ipplicahlo to <lc tprinin« whethor iho 1 intlfill nu»«>ts t luMondition iniÔU H I I J K J ) Iho opcrat ioinl s tand i rds in ^60 7'>^ ilio 1 ompliancn provisuins in 'toO 75'5 and Ihe monitoring provisions in <}60 7'JI)

§60 35c Reporting and recordkeeping guidelines

fo rapprovn i a S t i t e plan shall include the rrcordkuoping i n d reporting provisions li-,tpd in-'}SbO 757 i n d 60 7S8 IS applicable oxcept is provided undl r fe 60 24

,«•

§ 60 36c Compliance times (a) Except as p rov id t a for under

paragraph (b) of this section planning awarding of contracts and inst i l lat ion of MSW landfill air emission collection and control equipment capable of meeting the emission guidel ines established under § 60 33c shall be accomohshed within TO months a ' t e ' the e'fective aate of a State emission standard for MSW landClls

(b) For each existing MSW landfi'l meeting the condi t ions in §60 33c(a)(l) and s>60 33c(a)(2) whose NMOC emission rate is 'ess than 50 megagrams per year on the effective date of the State emission s tandard installation of collection and control systems capable of meeUng emission guidelines in § 60 33c shall be accompl ished within 30 months o f the date when the condit ion m § 60 33c(a){3) is met (i e the oate of the llrst annua l n o i m e i h a n e organic compounds emission rale which eoua 's or cxceeos 50 r i egag rans per year)

9 Part 60 is amended by add i rg a new subpart WWW to read as fo'lows

Subpart WWW—Standards o l Performance for Municipal Solid Waste Landfil ls

Sec 1)0 750 Applicability designauon ol

affected facility and delegation oi authontv

50 731 Definitions 60 752 Standards for air emissions from

municipal solid vvaste landfills 60 753 Operational stanoards to- collection

and contol systems 60 754 Test methods and procedures CO 755 Compliance provisions 60 756 Monitoring of operations BO 757 Reporting requirements OO ""Hi Recordkeepm;; rcquirenents t)0 7S9 specifications for active collection

systems

S u b p a r t W W W — S t a n d a r d s o f P e r f o r m a n c e fo r M u n i c i p a l S o l i d W a s t e L a n d f i l l s

§ 60 /SO Applicabil iry, designation of affected facility, and delegation o( authonty

(a) The provisions of this subpart apply to each munic ipa l solid waste

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1 indfill that commenced constnict ion rnconstruction or modification or began jccnpting waste on or after May 30, lOM I Physical or operational chniigus ni.ide to an exisUng MSW landfill solely lo comply with Subpart Cc of this purl arc not considered constniction reconstruction or modification for tho purposes of this section

(b) The following authorities shall bo retained by tho Administralor and not iransferrcd to iho Si^jte None

§ 60 751 Oeflnllions As used in this subpart ill terms not

dclinod herein shall haVe the meaning given them in the Act or in subpart A of this part

\cfjve collection ivstem means a gas collection system that uses gas mover equipment

Active landfill means a landfill m which solid wasle is bemg placed or a lindfill that IS p h n n e d to iccept waste in the futare

Closed landfill means a landfill in which solid waste s no longer being placed and in which no additional solid wastes will be placed without first fihng a notification ol modi*"cation as prescnbed u n d e r § 60 7(a)(4) Once a notitlcaiion of modification has been filed and addit ional solid waste is placed in the landfiU the landfill is no longer closed A Icindfill is considered closed after meetmg the criteria of § 258 60 of this title

Closure means that point in time when a landfill becomes a closec landfill

Commercial solid waste means all tvpes of sohd waste generated by stores offices restaurants warehouses and other nonmanufactunng activities excluding residential and industrial wastes

Controlled landfill means any landfill at which collection and control systems are required under this subpart as a result of the nonmethane organic compounds emission rate The landfill is considered controlled at the Ume either

(1) A noufication of intent to install a coUection and control system or

(2) A collecUon and control system design plan is submitted m compliance v^^th § 60 752(b)(2)(i)

Design capac i ty xaeaiis the maximum amount of s o h d waste a landfill can accept as specified in the construction or operating permit issued by the State local or Tribal agency responsible for regulating the landfill

Disposal facility means all contiguous land and s tmctures other appur tenances and improvements on the land used for the disposal of solid waste

Eintsiion rate c t i ( o / / m n n s the threshold anniuil emission rate to which a UindfiU coinpiiros its estimated omission n t o lo detprminc if control iiiulor tho regulation is required

Enclosed combustor means an enclosed firebox which maintains a relatively constant l imit id peak temperature generally using a liniitod supply of combustion air An enclosed flare is considered an enclosed combustor

Fliirr means an open combustor without enclosure or shroud

Ca i n w v r r equipment m a u m the equipment (i e , fan blower compressor) used to transport landfill gas through the header system

Household waste means any solid waste (including garbage, trash and sanitary waste in septic tanks) derived from households (including but not limited to single and mult iple residences hotels and motels bunkhouses ranger stations crew quarters campgrounds picnic grounds and day-use recreation areas)

Industrial solid wa?te means sol 'd waste generated by manufactunng or indus tna l processes that is not a hazardous waste regulated under Subtitle C of the Resource Conservation and Recovery Act, parts 264 and 265 of this title Such waste may mclude but IS not hmited to waste resulting from the following manufacturing processes electric power generation ferulizer/ agncultural chemicals food and related products/by-products inorganic chemicals iron and steel manufactunng leather and leather products nonferrous metals manufacturing/foundries, organic chemicals plastics and resins manufacturing pulp and paper mdust ry rubber and miscellaneous plastic products stone glass clay sind concrete products textile manufac tunng transportation equ ipment and water txeatmeat This term does not include minmg waste or oil and gas waste

In tenor well means anv well or similar coUecUon component located inside the perimeter of the landfill A per imeter well located outside the landfilled waste is not an m t e n o r well

Landfill means an area of land or an excavation m which wastes are placed for permanent disposal , and that is not a land application unit surface impoundmen t injeclion well or waste pile as those terms are defined under §257 2 of this title

Lateral expansion means a honzonta l expansion of the waste boundaries of an existing MSW landfill A lateral expansion is not a modification unless

It results in in increase in the design cap i< Uy of the lundfill

Municipal \oli(l wnsfe landfill or MSW landfill iTieaiib an entire disposal facility in a cont iguous geographical space where househo ld waste is placed in or on land An MSW landfill may i lso receive other typos of RCRA Subtitle D wastes (§ 257 2 of this title) such ns commercial solid waste, nonhazardous sludge cundit ionally exempt small quanii tv generator waste and industrial solid waste Portions of an MSW landfill may be separated by u cess r m d s An MSW landfill may be publii ly or privately owned An MSW landfill may be a new MSW landfill an existing MSW landfill or a lateral expansion

Municipal solid waste landfill emissions or MSW landfill emissions means gas generated by the decomposi t ion of organic waste deposited in an MSW landfill or d e n v e d trom ihe evolution of organic compounds in the waste

NMOC means nonmethane organic compounds as measured according to •he provisions of § 60 754

Nondegradable waste means any waste that does not decompose through chemical b reakdown or microbiological activity Examples are but are not l imited to concrete municipal waste combustor ash and metals

Passive collection system means a gas collection system that solely uses pos iuve pressure wi th in the landfill to move the gas rather than using gas mover equ ipment

Sludge means any solid semisobd or ' iquid waste generated from a munic ipa l commercia l or industr ial wastewater t reatment plant water supply t reatment plant or air pollution control facility exclusive of ihe treated effluent from a wastewater treatment p lant

Sol id waste means any garbage sludge from a wastewater treatment plant water supp ly treatment p lant or air pol lu t ion cont ro l facihty and other d iscarded m a t e n a l m c l u d m g solid, l iqmd senusohd , or contained gaseous ma tena l resul t ing from m d u s t n a l commercia l , mining, and agricultural operat ions a n d fi-om communi ty activities but does not inc lude solid or dissolved ma tena l in domest ic sewage or solid or d issolved materials in irrigation r e i u m flows or industr ial discharges that are point sources sub)ect to permits unde r 33 U S C 1342 or source special nuclear , or by-product material as defined by the Atomic Energy Act ot 1954 as amended (42 U S C 2 0 U e. s e q )

iiujficient dens i ty means any number spacing and combinat ion of collect ion

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9921

-ystem compononts including vertical wells horizontal collectors, and surlicc < ollcctors, necessary to niuintain

mission and migration cuiilrni as dLtermiiied by measures of porforniance set forth 111 this part

Sufficient e\trnctian rate means a rate sufficient to maintain a negadvo pressua* at all wollheuds in the collectiuii system without causing air innitration including any wellheads connected to the system as <\ result of exp insion or excess surface emissions for the life ofthe blower

§ 60 752 Standards for air emissions from municipal solid waste landfills

(a) Each owner or operator of an MSW landfill havmg a design capacity less than 2 5 million megagrams by mass or 2 5 million cubic meters by volume shall submit an initial design capacity report to the Administrator as provided in § 60 757(a) The landfill may calculate design capacity in either megagrams or cubic meters for co-nparison w iih the exemption values Any density conversions shall be documented and submitted with the report For purposes of part 70 permuting, a landfill with a design capacity less than 2 5 million megagrams or 2 5 million cubic meters does not require an operabng permit under part 70 of this chapter Submittal of the initial design capacity report shall a,lfill the requirements of this subpart except as provided for in paragraphs (a){li and (a)(2) of this section

(1) The owner or operator shall subTiit to the Administrator an anended design capacity report as provided for m § 60 757(a)(3), when there is any mcrease m the design capacity of a landfill subject to the orov^ions of this subpart wnether the increase results from an mcrease in the area or depth ofthe landfill a change in the operating procedures of the landfill or any other means

(2) If any mcrease m the maximum design capaatv of a landfill exempted from the provisions of §60 752(b) through § 60 759 of this subpart on the basis of the design capacity exempUon m paragraph (a) of this secUon results m a revised maximum design capacity equal to or greater than 2 5 million megagrams or 2 5 million cubic meters the owner or operator shall comply with the provision of paragraph (b) of this seaion

(b) Each owner or operator of an MSW landfill having a design capacity equal to oc greater than 2 5 miUion megagrams or 2 5 million cubic meters shall either comoly with p ingraoh (b)(2) of this section or calculate an MMOC emission rate for the landfill using the procedures

spefified in§60 734 The NMOC emission rate shall bo n calculated iiiuu illy except as provided in 5»liO 757(l>)(l)(ii) ol this subpart Tho owner or oper.itoi ol an MSW landfill s.ibiect lo this subpart with a design capacity greater than nr equal to 2 S imllion megagnnis or.: 5 million cubic m« t( rs iJ .ub)oct to p.ut 70 permitting reqiiirem< nts Win n i laiu'fill is closed and cither iievor needed i onlrol or meets tho conditions tor t ontrol svsiem removal specified in «) bO 752(b)(2)(v) ol this subpart T pirt ' 0 nperuirg pcrnut IS no longer required

(I) If the calculated NMOC emission rate is less than 50 megagrams per year the owner or operator shall

(i) Submit an annual emission report to the \dministrator except as provided form §60 75 7(b)(l)(u), and

(II) Recalculate the NMOC emission rate annually usmg the procedures specified in § 60 754(a)(1) unul such time as the calculated NMOC emission rate is equal to or greater tnan 50 megagrams per year or the landfill is closed

(A) If the NMOC emission rale upon recalculation required in paragraph (b)(l)(ii) of this section is equal to or greater than 50 megagrams per year the owner or operator shall install a collecUon and control system in comphance with paragraph Cb)(2) of this section

(B) If the landfill is permanently closed a closure notification snail oe submitted to the Administrator as provided for in § 60 757(d)

(2) If the calculated NMOC emission rate is equal to or greater than 50 megagrams per year the owner jr operator shall

(i) Submit a cohei 'ion and control svstem design plan preparea by a professional engineer to the Administrator within I year

(A) The collection cinQ control system as aescribed in the pian shall meet the design reqmrements of paragraph (b)(2)(ii) of this section

(B) The collectioi and control system design plan shall include any altemauves to the operational standards, test methods procedures compliemce measures motutormg, recordkeeping or reporting provisions of §§60 753 through 60 758 proposed by the owner or operator

(C) The collecUon and control system design plan shall either conform with specifications for acuve collection systems in § 60 759 or include a demonstration to die Administrator s satisfaction of the sufficiency of the alternative provisions to § 60 750

(D) The Administratur shall review the information submitted under

paragraphs (b)(2)(i) (A) (B) and (C) of this secfion .\nd either approve it (lis.ipprove it or request that additional mformaUon be submitted Because of the many site-specific factors mvolved with landfill gas system design 'iltcrnativ« systoms may be neci'ssary A wide variety of system designs are possible, such as vortical wells I ombination horizontal and vertical collection systBius or horizontal trendies only Lacli ite collection components and passive systems

(ll) Install <i collection and control system within 18 months ofthe submittal ot the design plan under paragraph (b)(2)(i) of this section that cffecuvely captures the gas generated within the landfill

(Al An active collecUon system shall [1] Be designed to handle the

maximum expected gas flow rate from the entire area ofthe landfill that warrants control over the intended use period of the gas control or treatment jystem equipment

[2] Collect gas from each area cell or grouD of cells in the landfill in which the initial solid waste has been placed for a penod of

(0 5 years or more if active or [li] 2 years or more if closed or at final

grade (J) CoUect gas at a sufficient

extraction rate, f-?) Be designed to minimize o ^ site

migration of subsurface gas (B) A passive coUection system shall (3) Comply with the provisions

specified in paragraphs (b)(2)(a) [ \ ) [ l ) [2], and (4) of this secUon

(2) Be installed with liners on the bottom and all sides in all areas in which gas is to be collected The hners snail be installed as requred under §258 -.0 of mis ntie

(ill) Route all the collected gas to a control system that complies with the requirements in either paragraph (b)(2)(iii) (A) (B) or (C) of this section

(A) An open fiare designed and operated in accordance with §60 IB

(B) A control system desig-ied and operated to reduce NMOC by 98 weight-percent or when an enclosed combustion device is used for control to either reduce NMOC by 98 weight percent or reduce the outlet NMOC concent-ation »o less than 20 oarts per million by volume dry basis as hexane at 3 percent oxygen The reduction efficiency or parts per million by volurae shall be established by an initial performance test requfcd under § 60 8 using the lest methods specified m §ba 754((1)

(l) 11 a boiler or process heater is used as the control device the lindfill gas


Attachment F

Landfill Cover Soil Quality Assurance

41

118


116 5851 ,17 I-

109 6095

1109

109 3043

- 3 - - - , I

111 5652

IJO

Moisture Content W°'o

13

Figure F-1 Standard Proctor Curve - Soil Clod Matenal from Trench I

42

1

'17

<

I 1,5

a Ml

n ' 107 2 107 2


STD Proctor/Sandia/LVH' "A " Ma-enal

14 1 J

IVl3icture Csntent W^

Figure F-2* Standard Proctor Curve - Soil from Trench I

•T=S'

A I E ^ A : I Z

43


Sieve Size 3/4" 3/8" #4 #10 #20 #40 #60

#140 #200

% Passing 100 95 0 82 0 75 5 67 8 646 60 0 39 5 35 8

Table F-1. Particle Size Distnbution - Trench I Soil (Clods)

Particle Diameter (mm) 0 023 0017 0012 0 009 0 007 0 006 0004 0 003 0 002

% Finer 99 9

27 5 25 2 23 8 218 115 28 27 20

Table F-2. Hydrometer Results from Table F-1 with #200 Control Sieve (Trench 1)

Sieve Size I"

3/4" 3/8" #4 #10 #20 #40 #60 #140 #200

% Passing 100 92 4 78 I 66 7 59 8 56 I 53 8 48 8 34 8 33 8

Table F-3 Particle Size Distnbution - Trench 2 Soil (Loose)

44


Density of soil samples by the Clod Method - Trench 1

Soil from Sunnse Mountain Landfill, Las Vegas, Nevada

Sample

No Location Depth Test Methcxi

Wt pan(g) Wt pan -I- paper (g) Wt Sample-f pan -i- paper (g) Wt Sample + Pan - Paper + acrylic (g) Length of wire used (cm) Total Wt Hair Net (g) Wt Hair Net not used (g) Wt Hair Net used (g) Wt Label (g) Wt Pan -I- Paper -i- Net + Wire + Sample -f Acrylic -i- Label (g) Wt Soil lost (g) Wt Sample - Net -i- Wire -t- Acrylic + Label + Scran (g) Wt Pan + Paper -f- Sample -t- Net + Wire + Acrylic + Label + Seran (g) Moisture content of Sample (% by Weight) Density of hair Net (g/cm' 3) Density of wire (g/cm' 3) Unit weight of wire (g/cm) Density of Seran (g/cm' 3) Wt water-I-beaker - Test No 1(g) Wt Water + beaker + submerged sample - Test No 1 (g) Length of wire not submerged - Test No I (cm) Water temperature - Test No I (degrees C) Density of water -Tesl No 1 (g/cm' 3) Wt water -i- beaker - Test No 2(g) Wt Water -i- beaker -t- submerged sample - Test No 2(g) Length of wire not submerged - Test No 2 (cm) Water temperature - Test No 2 (degrees C) Density of water -Test No 2 (g/cm' 3) Volume Sample -i- Net -i- Wire -i- Seran - Test No Volume Sample - Test No 1 (cm' 3) Volume Sample -i- Net -t- Wire -f Seran Volume Sample - Test No 2 (cm- S) Wt Air Dry Sample - Loss (g) Wl Dry Sample - Loss (g) Density Soil - Test # 1 (g/cm' 3) Density Soil - Test # 2 (glcm' 3)

Liquid limit = 23, Plastic limit = 21

IA Unknown Unknown Seran coat with net

245 95 250 95 395 64 395 64 120 0 0 13 Oil 0 02 0 14

395 89

1 (cm^3)

Test No 2(cm^3)

IB Unknown Unknown Seran coat with net

243 65 248 65 442 75 442 75 120 0 Oil 0 09 0 02 0 12

443 03

2A Unknown Unknown Seran coat with net

244 86 249 86 441 44 441 44 120 0 0 11 0 09 0 02 0)3

441 68

0 04 0 22 150 57 199 91 40152 448 56

5 80 1 09 6 45

000115 130

2518 38 2590 28

86 0 23 4

0 99733 2513 86 2585 71

86 4 23 4

0 99733 72 09 67 74 72 04 67 69 144 65 136 72 2 0184

2 0199

5 80 109 6 45

000115 1 30

2522 24 2615 60

82 8 23 4

0 99733 2509 23 2602 44

86 4 23 4

0 99733 93 61 89 33 93 46 89 18 193 88 183 25 2 0514

2 0548

Oil 197 45 447 31

2B Unknown Unknown Seran coat with net

180 34 185 34 404 79 404 79 120 0

0 13 0 11 0 02 0 16

405 06

0 07 225 97 411 31

5 90 1 09 6 45

000115 1 30

2520 31 2612 35

82 0 23 4

0 99733 2506 22 2598 14

86 4 23 4

0 99733 92 29 87 93 92 17 87 81 191 47 180 80 2 0562

2 0590

5 90 1 09 6 45

000115 1 30

2516 21 2622 40

86 0 23 4

0 99733 2511 42 2617 49

86 0 23 4

0 99733 106 47 101 64 106 35 101 52 21938 207 16

2 0381 2 0406

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Ave Bulk Density - Dry (g/cm' S) Ave Bulk Density - Dry (Ib/ff S) =

Average of tests IA, IB, 2A and 2B (g/cni^3) =

Average of tests IA, IB, 2A and 2B (Ib/ff^S) =

2 0191 2 0531 2 0576 2 0393

126 051 128 171 128 454 127 312

2 042

127 497

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Sunnse Mountam Landfill Fmal Cover Evaluation

Attachment G

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