lowry landfill superfund site - explanation of … · file plan lortry landfill sup^efund site...

UNITED STATES CNVIRON?" iVAL -KOTECTION AGENCYRE; .n v\\i

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SDMS Document ID

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FILE PLAN

LOrtRY LANDFILL SUP EFUND SITE

EXPLANATION OP SIGNIFICANT DIFFERENCES

If-95

P/irXr-d on Recycled Pnjxr

LOWRY LANDFILL SUPERFDND SITEEXPLANATION OF SIGNIFICANT DIFFERENCES

August 14, 1995

INTRC'-UCTION

The purpose of this documer' is to explagin the significantdifferences between the remedy Delected in the Record of Decision(ROD) for the Lowry Landfill Superfund Site in Arapahoe County,Colorado (Site), issued by the U.S. Environmental ProtectionAgency (EPA) on March 10, 1994, and the remedy described herein.The changes to the ROD have been made as a result of newinformation that EPA received subsequent to the issuance of theROD and do not fundamentally alter the sitewide remedy presentedin the ROD. The sitewide remedy for the Site remains protectiveof human health and the environment.

EPA is the lead agency for overseeing the cleanup of the Site;the Colorado Department of Public Health and the Environment(CDH) is the support agency.

This Explanation of Significant Differences (BSD) provides abrief history of the Site, describes the remedy selected in theROD, and explains the ways in which the remedy described hereindiffers from the remedy selected in the ROD. It also summarizesthe support agency's comments on the changes to the remedy anddiscusses compliance with all legal requirements.

This BSD is prepared in fulfillment of EPA's public participationresponsibilities under Section 117(c) of the ComprehensiveEnvironmental Response, Compensation, and Liability Act of 1980,42 U.S.C. Section 9601, et seq.. (CERCLA or Superfund) , as amendedby the Superfund Amendments and Reauthorization Act of 1986(SARA), and Section 300.435(c)(2)(i) of the-National ContingencyPlan (NCP), 40 C.F.R. Part 300. These lawo and regulationsrequire EPA to publish an BSD when the remedy to be implementeddiffers significantly from the remedy described in the ROD.

The administrative record, which contains this BSD and thedocumentation supporting it, is available for public review atthe following location:

EPA Superfund Records Center999 18th Street . '5th floor North TerraceDenver, Colorado 80202(303) 293-1807Hours: Monday-Friday - 8:00 a.m. to 4:30 p.m.

This BSD will also be made availc,ole at the following LowrySite information repository:

Aurora Public Library14949 East Alameda DriveAurora, Colorado 8001*(303) 340-2290Hours: Monday-Thursday — 10:00 a.m. to 10:00 p.m.

Friday and Saturday — 10:00 a.m. to 6:00 p.m.Sunday — 12:30 p.m. to 6:00 p.m.

A notice of availability and brief description of the BSD waspublished in the Denver Post on Tuesday, August 15, 1995, asrequired by CERC'jA Section 117 (c) .

SUMMARY OF SITE HISTORY, CONTAMINATION PROBLEMS,AND SELECTED REMEDY

Summary of Sit® History and Contamination Problems

The Site is located northeast of the intersection of QuincyAvenue and Gun Club Road, approximately 15 miles southeast ofdowntown Denver and two miles east of the City of Aurora,Colorado (Figure 1). In 1930, the City and County of Denver(Denver) purchased land including the Site to attract an Army AirCorps Technical School to Denver. In 1937, the Denver CityCouncil conveyed title to the land to the Federal government.From about 1940 to 1962, the U.S. Air Force used the Site as abombing range. In 1964, the United States conveyed all orportions of the five sections of the bombing range back to Denverby Quitclaim Deed.

From 1966 until 1980, Denver operated a municipal landfill atSection 6 on the Site, accepting liquid and solid municipal andindustrial wastes, including sewage sludge. (Section 6 is theprincipal area of the Superfund Site. Section 31, directly tothe north of Section 6, is currently used for municipallandfilling.) These materials included hazardous substances,such as volatile organic compounds and heavy metals, listedpursuant to 40 C.F.R. Section 302.4.

From 1966 until 1980, approximately 138 million gallons of wastewere disposed of at the Site, primarily by a disposal practiceknown as "co-disposal." Approximately 75 unlined waste pits ortrenches were excavated to accommodate a mixture of municipal andindustrial wastes. In the southern half of Section 6, the pitswere filled about three-quarters full with liquid wastes andtopped with 25 to 60 feet of municipal refuse. The waste pitsranged from approximately 15 to 30 feet in depth, approximately100 to 1,100 feet in length, and approximately 50 to 150 feet inwidth. Over time, the liquids seeped out of the pits and mixedwith the surrounding refuse and ground water. In the north-central portion of Section 6, excavated pits were filled withliquid wastes and municipal refuse, then covered with two tofive feet of native soil and discarded tires. Over time,

these liquid wastes seeped out to ground water and to surfacewater in Unnamed Creek. Approximately 8 million tires werestockpiled at the Site in the 1970f

From 1969 until 1986, munici:a"i • ;v -ge sludge was applied toapproximately 160 acres alor, < ' h' northern and eastern boundariesof Section 6. The sludge waa applied to the surface of the landand then incorporated into the native soils. After 1980,leachate collected in on-site surface impoundments was injectedin the same 160-acre area. Both the municipal sewage sludge andthe leachate contained hazardous substances listed pursuant to 40C.F.R. Section 302.4.

Preliminary investigations at the Site began in the mid-1980s.Various parties, including EPA, CDH, and Denver, performedstudies before 1984, when the Site was placed on the SuperfundNational Priorities List. Contaminants were found in surfacewater and sediments, ground water, soils, and landfill solids.From 1984 to 1993, a series of remedial investigation/feasibility studies (RI/FSs) were performed to study the natureand extent of the contamination and to investigate the potentialthreats that the Site posed to human health and the environment.Contaminated surface water and shallow ground water at the Siteare currently being addressed through two interim remedialmeasures: a ground-water barrier wall/treatment facility and theSurface Water Removal Action (SWRA). The ground-water barrierwall and SWRA are key components of the sitewide remedy selectedin the ROD.

EPA conceptually divided the Site into six Operable Units (OUs)for response and grouped them according to the media that theyaddress: OUs 1 and 6 address shallow ground water, subsurfaceliquids, and deep ground water; OUs 2 and 3 address landfillsolids and gas; and OUs 4 and 5 address soils, surface water, andsediments. Each medium contains hazardous substances listedpursuant to 40 C.F.R. Section 302.4. The primary threats at theSite are posed by: le.ndfill gas; waste-pit liquids; contaminatedground water; and buried drums, drum contents, and contaminatedsoils within the former tire pile area.

Summary of Selected Sitewide Remedy

Under the selected sitewide remedy, contaminated ground waterwill be addressed through containment, collection, and treatment,utilizing the existing treatment facility or an upgradedfacility. Landfill gas will be addressed through containment,collection, and treatment using enclosed flare technology.Contaminated seepage and suriace water are addressed through adrainage and underground collection system in the Unnamed Creekarea as part of the SWRA. The response action identified forthe former tire pile area will address principal threats (drums,drum contents, and contaminated soils) through treatment and

offsite disposal to recUxce the ttf^icity, mobility, and volume ofcontaminants. Landfill mass solids and soils are low-levelthreats at the Site that will be addressed through containment.

DESCRIPTION OF SIGNIFICANT DIFFERENCES ANDTHE BASIS FOR THOSE DIFFERENCES

Summary of Information Giving Rise to the Significant Differences

The changes memorialized in this BSD are based on comments thatwere submitted by Denver, Waste Management of Colorado, Inc., andChemical Waste Management, Inc. in a letter dated December 27,1994. EPA considered the comments and determined that theinformation supports the need to correct and/or clarify certainaspects of the remedy described in the ROD. These changes do notfundamentally alter the overall approach of the sitewide remedyor any individual component of the sitewide remedy.

Description of Significant Differences

The significant differences are as follows:

(1) Table 11-2, Ground-Water Compliance Boundary PerformanceStandards for the Sitewide Remedy.

(a) The standard for hexachlorocyclohexane, alpha (alphaBHC), which was listed incorrectly in the ROD as 0.2jig/I, is corrected to 0.006 /xg/1.

(b) There are several risk-based ground-water performancestandards whose values are less than those for MaximumContaminant Levels (MCLs) or Colorado Basic Standardsfor Ground Water (CBSGWs). Risk-based standards arederived from slope factors and reference doses (RfDs).Slope factors estimate excess lifetime cancer risksassociated with exposure to potentially carcinogeniccontaminants. Slope factors are based on the. resultsof human epidemiological studies or chronic animalbioassays to which animal-to-human extrapolation anduncertainty factors have been applied. RfDs are usedto indicate the potential for adverse health effectsfrom exposure to contaminants exhibiting non-carcinogenic effects. RfDs are based on the results ofhuman epidemiological studies or chronic animalbioassays. MCLs establish health-based standards forpublic drinking water systems. CBSGWs establish waterquality standards for both classified and unclassifiedground water.

Where an MCL or a CBSGW exists for a given contaminant,the MCL or CBSGW standard shall be met instead of the

risk-based standard. Hoover, where no MCL or CBSGWexists for a given contaminant, a risk-based standardshall be met. The r^d^f'cations are shown in Table 1,which is attached :< t'li BSD an part of Appendix A.

(c) There are several L: • n fc ic contaminants whoseperformance stand^n's iic be less than backgroundconcentrations. EPA has praviously stated that it willnot require cleanup of inorganic contamination to belowbackground levels. Therefore, once backgroundconcentrations have been established and approved byEPA, these values will be incorporated into theperformance standards for pertinent inorganiccontaminants.

(d) Some contaminants have performance standards whosevalues are less than the Practical Quantitation Limits(PQLs). The term PQL is defined as the level at whichthe concentration of a given contaminant can bequantified (or measured) using existing analyticalmethods. For those contaminants where the PQL exceedsthe regulatory value, the PQL shall be the standard.The modifications are shown in Table 2, which isattached to this BSD as part of Appendix A.

(e) There are a number of contaminants for whichperformance standards have been listed in Table 11-2,but which have not been listed as chemicals of concernin Table 7-1. Although these contaminants have notbeen found at the Site to date, they have performancestandards associated with them that shall be met ifthey are found at the Site. Contaminants that have notbeen previously detected at the Site shall be initiallytested for, and indicator parameters shall be monitoredwith limited frequency thereafter.

(f) The ROD provides performance standards for bothdichloromethane and meth/lene chloride. However, sincedichloromethane is another name for methylene chloride,dichloromethane is deleted from the list ofcontaminants. In addition, the original performancestandard for methylene chloride (0.19 /ig/1) , which wasbased on water quality criteria, is changed to 5 MSfA/which is the MCL for this contaminant.

(g) Xylene was inadvertantly entered into the table twice.One of the entries is deleted.

(h) Tritium was inadvertently entered into the table twice.The tritium performar-.ce standard of 880 pCi/1, which isa risk-based standard, is deleted and the CBSGWs valueof 20,000 pCi/1 remains.

(i) The performance standard for gross alpha (15 pCi/1)excludes concentration contributions from radon anduranium.

A revised version of Tablr 11-2 :1u attached to this BSD asAppendix B.

(2) Table 11-5 of the ROD presents the air quality performancestandards for the sitewide remedy. Numerical values for threechemicals were reported incorrectly in the ROD and are thereforechanged to reflect the correct values. The revised table isattached to this BSD as Appendix C. All contaminants listed inTable 11-5 that have not been previously detected at the Siteshall be initially tested for, and indicator parameters shall bemonitored with limited frequency thereafter.

(3) Table 11-6 of the ROD presents the landfill gas Point ofAction (POA) boundary standards, and Table 11-7 presents thelandfill gas compliance boundary performance standards. Risk-baaed values for several chemicals within Table 11-7 differ fromthe values for the same chemicals within Table 11-6. The reasonfor the difference is that the risk-based values in Table 11-7were calculated using an age-adjusted equation to normalize thetarget concentration for both resident children and adults. Thechemicals in Table 11-6 should have been subjected to similarage-adjustment calculations. Therefore, the values in Table 11-6are changed to reflect the age-adjustment methodology. Therevised table is attached to this BSD as Appendix D.

(4) The ROD requires that the ground-water POA boundary bemonitored to provide sufficient warning such that responseactions can be taken to prevent violations of performancestandards at the ground-water Point of Compliance (POC) boundary.The basis for the numeric standards at the ground-water POAboundary are the CBSGWs.

Portions of the ground-water POA boundary are located between themain source area and the ground-water containment systems on theeastern, western, and southern boundaries of the landfill mass.Ground water degradation beyond the POA boundary will occur ifcontaminated ground water is allowed to flow toward thecontainment systems. Given that the purpose of the containmentsystems is to collect migrating contaminated ground water, it isnot appropriate, from a technical standpoint, to establish aground-water POA boundary in areas where, through implementationof the remedy, ground water may be expected to migrate beyond theground-water POA boundary.

Therefore, the.ground-water POA boundary shall be coincident withthe ground-water POC boundary along th? eastern, western, andsouthern sides of the landfill mass, as well as along the lengthof the northern barrier wall. The revised ground-water POA

boundary is presented in Figure 11-2, which is attached to thisBSD as Appendix E.

(5) The following parag^e ?h u l''r Subsection 11.2.1.1 of the RODis modified to be consit :< it w ;:i the changes to the ground-waterPOA boundary described i.i Jterr 1 above. The modification, whichis shown in italics, is ar fol yiB:

"The selected ground-witer remedy also includej a Pointof Action (POA) bounda^ry (Figure 11-2} . Table 11-3identifies numeric standards for the POA boundary whichare based on the Colorado Basic Standards for GroundWater [5 CCR-1002-8 (3.11.5c)J. The POA boundaryencompasses the highly concentrated waste-pit liquidsand ground water at the north end of the main sourcearea and unnamed creek. Ground-water monitoring shallbe conducted at the POA boundary and additionalmeasures, as described in the next section, shall betaken if Table 11-3 standards are exceeded at the POAboundary. The POA boundary has been established toprovide sufficient warning such that response actionscan be taken to prevent violation of performancestandards at the compliance boundary. The physical/surveyed location of the compliance boundary and thePOA boundary shall be determined by EPA during RD."

(6) Subsection 11.2.2.1 of the ROD presents the performancestandards and points of compliance for the ground-water treatmentplant. To further clarify the discussion, two sentences, whichare shown in italics, 'are added to the first paragraph of thissubsection:

"The ground-water treatment plant shall meet water andair quality performance standards presented in Tables11-2 and 11-5 of this ROD, respectively, no later than60 days after the startup of a new or upgraded ground-water treatment plant, or no later than 60 days after adetermination by EPA that the existing treatment plantmay be used without an upgrade. These performancestandards shall supersede the performance standardsidentified in the SWRA Consent Order. However, untilthat time, the performance standards identified in theSWRA Consent Order shall remain in effect. The pointof compliance for the ground-water treatment planteffluent shall be existing Port 13 of the treatmentplant or its equivalent in the upgraded or newtreatment plant. The point of compliance for airemissions at the ground-water treatment plant shall Jbeat the plant discharge point. Performance standardsshall be calculated during RD using air dispersionmodeling."

(7) Subsection 11.4.1 of the ROD presents the performancestandards and points of compliance for the landfill gas componentof the selected remedy. In the fourth paragraph of thissubsection, Table 11-7 is lacorrectly referenced; Table 11-5 wasmeant to be referenced instead. In addition, to further clarifythe discussion in the fourth paragraph, a sentence is added tothe fourth paragraph of tJ'it subLie^tion. Both the correction andclarification are shown i- talir.s below:

"Flare emissions snail be measured at the enclosedflare stack and shall attain Table 11-5 performancestandards. The flare shall meet the New SourcePerformance Standards (40 C.F.R. Section 60.18);compliance shall be determined by testing for volatileorganic compounds using procedures approved by EPA.Performance standards shall be calculated during RDusing air dispersion modeling. "

SUPPORT AGENCY COMMENTS

CDH concurs with the BSD and the changes to the selected remedy.

AFFIRMATION OF STATUTORY DETERMINATIONS

Considering the new information that has been received and thechanges that have been made to the selected remedy, EPA and CDKbelieve that the remedy remains protective of human health andthe environment, complies with Federal and State requirementsthat are applicable or relevant and appropriate to this remedialaction, and is cost-effective. In addition, the revised remedyutilizes permanent solutions and alternative treatmenttechnologies to the maximum extent practicable for this Site.

EbHert li. Duprey, Dttectov?' DateHazardous Waste Marfageme/rc DivisionU.S. EnvironmentatxProtection Agency, Region 8

Howard Roitman, Director DateHazardous Materials and Waste Management DivisionColorado Department of Public Health and Environment

8

LIST OF ACRONYMS

ARARs Applicable or Relevant and Appropriate RequirementsCBSGWs Colorado Basic Standardn for Ground WaterCDH Colorado Department of JMblic Health and Environment

(also known as CD?T?E)CERCLA Comprehensive Environmental Response, Compensation, and

Liability Act of 1980C.F.R. Code of Federal Regular ionsEPA U.S. Environmental Protection AgencyBSD Explanation of Significant DifferencesMCL maximum contaminant level/xg microgramMSW Municipal Solid WasteNCP National Oil and Hazardous Substances Pollution

Contingency PlanOU Operable UnitpCi/L picocuries per literPDA Point of ActionPOC Point of CompliancePQLs Practical Quantitation LimitsRD Remedial DesignRI Remedial InvestigationROD Record of DecisionSARA Superfund Amendments and Reauthorization Act of 1986SWRA Surface Water Removal Action

\BucktoyAil Natond Guard

Bow

LEGEND

~- Roads*~\ Topographic Contours (interval 501)

11 Section Number

Lowry Site

DADS

:oo> me

The locations shown are approximate.

Figurs 1THE LOWRY SfTE

Appendix ATables 1 and 2

Table 1Risk-Based Stct'djirds Tfa'ir Are Less Than MCLs/CBSGWs

Contaminant

1 , 1 -Dichloroethylene

1 , 1 ,2-Trichloroethane

1 ,2-Dichloroethane

1 ,2,4-Trichlorobenzene

Benzene

Bis(2-chloroethyl)ether

Carbon tetrachloride

Chloroform

Methylene chloride

Pentachlorophenol

Tetrachioroethylene

Trans- 1 ,3 -dichloropropene

Trichloroethylene

Vinyl chloride

Arsenic

Nickel

Thallium

Strontium-90

Thorium-230

Thorium-232

Uraniurn-234

Uranium-235

Uranium-238

RODPerformance

Standard 0<g/l)

0.068

0.32

0.2

20

0.62

0.016

0.026

0.19

0.19

0.71

1.5

3.4

2.6

0.037

0.049

2

1.1

. 1.3 pCi/1

3.7 pCi/1

12 pCi/1

3.0 pCi/1

20 pCi/15.2 pCi/1

RevisedPerformance

Standard 0*g/D

7

3

0.4

70

5

0.03

0.3

6

5

1

5

87

5

2

50

100

2

8.0 pCi/1

60 pCi/1

60 pCi/1

26 pCi/1

26 pCi/1

26 pCi/1

table 2MCLs/CBS^Ws That ,*re Less Tl

Che-fcnl

t ,2-Dichlorocthane

1 ,2-Dichloropropane

1 ,2,4,5-Tetrachlorobeii^ne

2,3,7,8-TCDD (dioxin equivalent)

2,4-Dichlorophenol

2,4-Dinitrophenol

2,4,6-Trichlorophenol

Aldicarb

Aldicarb Sulfone

Aldicarb Sulfoxide

Aldrin

Benzidinc

Benzo(a)anthracene


Bis(2-ethylhexyl)phthalate

Bromodichloromethane


Chlordane

Di(2-ethylhexyl)phthalate

Dieldrin

Endothall

Ethylenedibromide

Heptachlor

Heptachlor Epoxide

Hexachlorobenzene

Hexachlorobutadiene

Hexachlorocyclohexane, Alpha

Nitrobenzene

PCBs

Pentachlorobenzene

Pcntachlorophcnol

Toxaphene

tan Current PQLs

PerformanceStandard 0>g/l)

0.4

0.56

2

0.0000002

21

14

2

3.0

2.0

4.0

0.002

0.0002

0.0031(total PAHs)

0.03

6.1

0.3

0.3

0.004

6

0.002

100

0.05

0.008

0.09

1

1

0.006

3.5

0.005

6

1

0.03

PQL(Mg/D

1

1

10

0.01

50

50

10

10

3

20

0.1

10

10

10

20

1

1

10

10

0.1

115

10

0.05

0.1

10

10

0.05

10

0.05

10

10

5

Appendix BRevised Table 11-2

T'iMelI-2Ground-Water Compliance Boundary Performance Standards

Sitev.ide Remedy Page 1 of 5

Chemical

Concentration (jift/I)

PerformanceStandard PQL Basis

Organics

1 ,1-Dichloroethiuie

1,1-DkhloroethyIene

1 ,2-Dichloroethylene(cis)

1 ,2-Dichloroethylene(trans)

1 , 1 , l-Trich!oroethane

1 ,1 ,2-Trichloroethane

1 , 1 ,2,2-Tetrachloroethane

1 ,2-Dibromo-3-ChIoropropane

1 ,2-Dichlorobenzene

1,2-Dichloroethane

1,2-Dichloropropane

1 ,2-Diphenylhydrazine

1 ,2 ,4-Trichlorobenzene

1,2,4,5-TetracUorobenzene

1 ,3-Dich!orobenzene


2-Butanone

2-Chlorophenol

2-Hexanone

2-Methylnaphthalene

2,3,7,8-TCDD (diorin equivalence) ' : :

2,4-D (dichlorophenoxyacettcacid)

2,4-DkUorophenol . :

2,4-Dmitrophenc4 .. • -''•'••• ;

2,4,5 TP (tricbloropbeaozypropiomc acid)

2,4,6-Trichlorophenol

4-Methyl-2-penumons

Acstone

Alachlor

Aldicarb

Aldicarb Sulfone

Aldicarb Sulforide

9907

70

100

200

3

0.089

0.2

600

0.4

0.56

0.05

70

2

620.

75

780

0.1-

0.0031(total PAHs)

.00000022

70

2114

SO2

7801,600

2.0

3.0

2.0

4.0

1I

10

0.2

50

50

50

10

3

20

C

A

DD

D

A

B

D

D

A

D

D

A

D

D

A

C

A

-

A

A

D

A

A

D

D

C

C

D

D

D

D

Note»: A = ARAR/TBC.B = Carcinoscmc (1 x 10*) t»rget risk for adult.C = Noncareinogenic target conr^i.i: ! >n for child.D = Colorado Basic Standards for Ground Water for chemicals that

are not COCa.— = No information availablePQL = Practical qunnliution limit. level at which the concentration of a

given chemical cnn be quantified using existing analyticalmethods. Tor those chemicals where the PQL exceeds theregulator)' value, the PQL will be utilized for measuringcompliance.

;;v-; = Performance standard has been changed from the value published inthe ROD and/or a PQL has been added.

Table 11-2Ground-Water Compliance Boundary Performance Standards

SitewiUe Remedy Page 2 of 5

Chemical

AMrin

Atrazine '

Benzene

Benzidme

Benzo(a)anthracene

Benzo(a)pyrene (PAH)

Benzyl Alcohol

bis(2-Ch!oroethyl)ether

bis(2-E*hyIhetyl)plilhalate

BromodkUoromethane

Bromoform

Carbazole

Carbofuran

Carbon tetrachlorido

Chlordane

Chlorobenzene

Chloroe thane

Chloroform

Chlorophenol '

Dalapon

DDT Metabolite (DDE)

DDTDi(2-ethylhexyl)adipate

Di(2-*thylhexyl)phthalate

Di-n-Octylphth«l«te

Dibenzofuran

Dibromochloromethane

Diddrin

Dinoieb

Diquat

Endothall

Endrin

Endrin Aldehyde

Ethylbenzene

Concentration (w?/l)

PerformanceStandard

0.002

3.05

0.0002

0.1

0.2

-

0.03

6.1

0.3

4.0-

36

0.3

0.03

100

-

6

0.2

200

0.1

0.1

4006

-

-

14

0.002

7

20

1000.2

0.2

680

PQL

0.1

10

10

• 10

1

11.0

10

0.1

115

Basis

D

D

A

D

A

D-

A

B

D

D-

D

A

D

D-

A

D

D

D

D

D

D

-

-

D

DD

D

D

D

D

D

Note*: A = ARAR/TBC. .B = Carcinogenic (1 x 10*) target risk for adult.C = Noncarcinogenic target concentration for child.D = Colorado Basic SUrdiirds for Ground Water for chemicals that are

not COCa.- = No information aviiieble.PQL = Pnctical quantitation limits, cvel at which the concentration of a

given chemical can be quantified using cxi.iting analytical method!.For those chemicals when: Uic PQL exceeds the regulatory value, thePQL will be utilized for measuring compliance.

> -lfi; = Performanco standard his been changed from the valu: published inthe ROD nnd/or a PQL hns been added.

Tyle ;l-2Grouno-Waf- C • plianc 01 -•dary Performance Standards

Site^ '.e m-K'y Page 3 of 5

Cbemic il

Ethylenedibroraide

Fluonnthene

Olyphosate

Heptachlor - ..• . : •'•

Heptachlor Epoxide

HexacbJorobenzene •. •• : •. : •

Hexachlorobtitadiene : '"•'•''

Hexacblorocyclobexane, Alpha ' . .

Hexachlorocyclohexane, Gamma (Lindane)

Hexachlorocyclopentadiene

Iiophorone

Malathion v . '• ; •

Methoxychlor

Methylene chloride . . . ; • • • • ' .

Monotrydric phenol ; :"'';".'"•' V'.. " ••.'.

.Naphfl^we^-:?:'--S->-V''-:.:. . • • ••• '-:; •^•:- ' : •

Nitrobemene •::.'•••:•'•..••• ''•. ;--;f. • . .;;: :. -,-,. •:•••• ••.':•• •'•

Oxamyl (vydate)

PCBs" ' •:-:.:"::-i-,:.x.:;.: • ; • • • : • > A V - . v r - /

Fentachlorobeozene ': ; ,-5; '.y* •••'•••. \.:'-'----

.Pentacblorophenol :. ; ;: :

Phenanthrene

•PHenol- ' . . : - : . : . . •' ' •/• ' .•::. . • -

Piclonm

SimizineStyrene

Tetrachloroethylcnc . • • • • . "Toluene

Toxaphcne : . • '.':

trans-13-Dicbloropropeite .

TrictaloroeUiylene

Concentration (jiR/1)

PerformanceStandard

0.05

188

7000.008

0.09

11

0.006

0.2

501,050

40

5

63

3.5

200

0.005

6

1

0.0031(total PAHs)

300

500

4100

5

1,000

0.03

87

5

PQL

0.05

1010

0.05

10

1.0

10

50

5

Basis

A

A

D

D

D

D

D

D

D

D

D*

D

A*

C

D

D

D

D

A

A

D

D

DD

A

A

D

A

A

Note*: A = ARAR/TBC.B = Carcinogenic (1 s 10*) target risk for adult.C = Noncarcinogenicurget concentration for child.D = Colorado Basic Standards fcr Ground Water for chemicals that

are not COCc.— = No information available.PQL = Practical quar.titation limiu, level at which the concentration of a

given chemical can be quantified using existing analyticalmethods. For those chemicals where the PQL exceeds theregulatory value, the PQL will be utilized for measuringcompliance.

S.H = Performance ctandard hao been changed from the value published intho ROD and/or a PQL has been ndded.

" = Chemical should not be in the table becauoo it is not a COC and doesnot hove « Colorado Baltic Sundard for Ground Water value

Tab1??!;-*Ground-Wa'er Co~i bonce I ID 1 'ry Performance Standards

SHewid. Rosiedy Page 4 of 5

Chemic&I

Concentration 0*8/1)

PerformanceStandard

Vinyl chloride ) 2

Xylenei (total) • 10,000

PQL Basis

A

D

In tames and I ".'cc.'lc. icons

Aluminum

Antimony

Arsenic - . - . • • • • •:'•

Aibeitoi (fibers/I)

Barium

Beryllium

Boron

Cadmium

Chloride

Cobalt

Coliform (total) per 100 ml

Color, color unita

Corrosivity

Copper

Chromium (as CrfVn)

Chromium (total)

Cyanide

Fluoride

Foaming Agents

Iron

Lead

Manganese

Mercury

Nkkei - . . ' • ' •• •' • . :; •••- :Nitrate ai N

Nitrate ird Nitrite ai N

Nitrite as N

pH

Selenium

Silver

Sulfite

5,000

6

SO

30,000

1,000

4

750

5

250.COO

50

1

15noncorrosive

200

50

50

200

2,000

500300

15

50

2

10010,000

10,000

1,000

6.5 to 8.5

10

50

250,000

D

D

A

D

D

D

D

D

D

A

D

DD

D

A

D

D

DD

D

A

A

D

A

D

Ti

D

D

D

D

D

Notes: A = ARAR/TBC.B «= Csrcinogenb (1 x 10*) target risk for adult.C = Noncarcinogcnic target concentration for child.D =» Colondo Basic Standards for Ground Water for chemicals that are

not COCs.— = No information available.PQL =• Practical qunn'itation iimita, 1 ,vel at which the concentration of a

given chemical can be qjan'.iiied using existing anslytical methods.For those chrmicals Mthr.re 'Vj P*QL exceeds tha reguletory value, thePQL will be utilized for measuring compliance.

::\.:f: = Performanco r.tindard hci hcxsn changed from iho value published inthe ROD nnd/or n PQL hnn been ndded.

•fr)Uel!-2Ground-Water Compliaac^ ''onndary Performance Standards

StcvHe Remedy Page 5 of 5

Chemical

Thfttlmin

Viiudium

Zinc

Concentration Oig/1)

PerformanceStandard

->

100

2,000

PQL Basis

A

D

D

Rauionudides

Americiuni-241

Beta and photon emitten, mrem/yr

Ceiium-134

Gross Alpha (excluding radon and uranium)

Uad-210

PIutonium-238, -239, and -240

Pbtassiimi-40 • ' : •' • ••. •• • - . • ' :' ' , -::;-. "

Radium-226 and -228

Stnratium-90Thorium-228

.Thoriuin-230 and -232. : :

Tritium

UranJnai'234 : . ';..:i::-.'-. •.- :';• ••'''-.•:• • • .

:Uraninm-235V: ::,/':.:::::':•' : '. •' .'•'^':'^'--'"^.-\

Uraniiim-238 ; .'.. VJ';'.-1"'1'.":1' -:?. . -'.fy.d

0.2 pCi/1

4

80 pCi/1

15 pCi/1

0.072 pCi/1

15 pCi/1

4.3 pCi/1

5 pCi/1

8.0 pCi/1

0.87 pCi/1

60pCi/l

20,000 pCi/1

3.0pCi/l

3.0pCi/l

1.7pCi/I

B

D

D

D

B

A

B

A

A

B

A

D

B

B

B

Note*: A = ARAR/TBC.B = Carcinogenic (1 x 10*) target risk for adult.C = Noncarcinogenictargst concentration for child.D = Colorado Basic Standard! for Ground Water for chemicals that are

not COCi.— = No information available.PQL = Practical quantitation limits, level tt which the concentration of a

given chemical can be quantified using existing analytical methods.For those chemicolo where the PQL exceeds the regulatory value, thePQL will be utilized for measuring compliance.

;..:.. -J — Performance standard has been changed from the value published in

the ROD and/or * PQL has been added.

Appendix CRevised Table 11-5

Tab'cll-SAir Quality Performarce Standards

Sittwide Remedy Page 1 of 3

Chemical/Element

ConcentrationOtg/m3)

AnnualAverage(AAL)

24-HourAverage(TEL) Other Source

Organics1,1, 1-Trichloroethane

1,1,2-Trichloroethane

1 , l-Dichloroethane1 , 1 ,2,2-Tetrachloroethane

1,2,4 Trichlorobenzene

1,2-Dichloroethylene (total)

1 , 1 -Dichloroethylene

1 ,2-Dichlorobenzene (ortho)

1 ,2-Dichloroethane

1 ,2-Dichloroethylene

1 ,2-Dichloropropane


2,3,7,8-TCDD(dioxinequivalence)

2,4-Dichlorophenol

2,4-Dimethylphenol2,4-Dinitrophenol

2-Butanone2-Chlorophenol

2-Hexanone

2-Methylphenol

2-Methylnaphthalene

4,4-DDT

4-Methylphenol

4-Methyl-2-pentanone

Acetone

Acrylonitrile

Aniline

Benzene

Benzo(a)anthracene

Benzyl alcohol


1038.37

0.06

--

0.02

-

107.81--

81.74

0.04

107.81

0.05

0.18

—

-

---

32.07--

10.88

-14.25'-

--

160.54

0.010.14

0.12„

--

--

1038.37

14.84

-

18.67

-

215.62--

81.74 .

11.01

215.62

94.23

122.61

—

-

---

32.07--

10.88

-14.25-

---

--

160.54

1.182.07

1.74-

--

--

---

521--

11-

0.049

--

----

—

-

---

---

-

--

0.0103--

-

--

-

--

-

--

--

--

Massachusetts Guidance


Noncarcinogenic Risk


Based on RfC


Carcinogenic Risk









Based on Slope factor





"Value io for sum of naphthalene and 2-mcthyl naphthalene.

Table U-5Air (JuMlity Performance Standards

"< SilewWe 't'.pr.ody -•••• Page 2 of 3

Chemical/Element

Bis(2-ethylhexyl)phthalate

Carbazole

Carbon disulfide


Chlorobenzene

Chloroethane

Chloroform

Chloromethanc (methylchloride)

Dibenzofuran

Dieldrin

Di-n-Octylphthalate

Ethylbenzene

Ethylenedibromide

Fluoranthene

Gamma BHC (lindane)

Heptachlor

Methylene chloride

Naphthalene

NDMA

PCBsPentachlorophenol

Phenanthrene

Phenol

Styrene

Tetrachloroethylene

Toluene

trnns-1 ,3-DichloropropeneTrichloroethylene

Vinyl chlorideXylenes (total)

Coniieiiirationr«f,/ra3)

AnnurAv a(AAL>

--

0.82

0.07

6.26

358.78

0.04

—

----

118.04

-

-

0.003

0.001

0.24

14.25"

-

0.00050.01

-

52.33

1.75

0.02

10.24

-

0.613.47 .11.8

?/-l,'<mrAve .;gr.CTEL)

--

0.8285.52

93.88

717.55

132.76

—

-

-

-

118.04

-

-

0.14

0.149.45

14.25'

-

0.0030.01

-

52.33

115.81

922.18

10.24

-

36.52

0.38

Other

-~

- •--

'- •

0.56

-

0.000219

-

-

-

-

- .-

-

-

0.0001

-----------

—11.8 {

Source

Massachusetts GuidanceMassachusetts Guidance




Based on Slope Factor








Massachusetts GuidanceMassachusetts Guidance






Massachusetts . GuidanceMassachusetts Guidance

'Value is for sum of naphthalene and 2-methyl naphthalene.

TS* le ll-c

\ir u .. "ty Peifonna) e St" ndards'Sfcewvi '«4s - -£ Page 3 of 3

Chemical/Element

1 Con-ieitra t:-nOigArrV

Annu 'Avera(AAL)

£;-HourA tefVgr-rr r , ) Other Source

Inorganics

Ammonia

Arsenic

BariumBeryllium

Cadmium

Chromium

Lead

ManganeseMercury

Nickel .

SeleniumVanadium

4.73

-

-

0.0004

0.001--

0.07

-

-

0.180.540.27

4.73-

-

0.001

0.003

-

0.14-

-

0.270.540.27

-0.0007

0.5--

0.000085

-1

0.3---



Based on Unit Risk





Based on RfC

Based on Unit Risk




•Value is for sum of naphthalene and 2-methyl naphthalene.

Appendix DEavised Table 11-6

Chemical

1,1-Dichloroethylene 3.3

1,2-Dichloroethane 6.4

Benzene 20

Chloroform 7.3

Methylene Chloride 360Vinyl Chloride 2.0

'Standard based on 10"4 excess cancer risk.

Appendix ERevised Point of Action Boundary

Figure 11-2

EASTHAMPDENAVENUE

V&!tS&

Existing Ground-Water Treatment PlantE--* T5^-^ *•'.£-*.

WMCMaintenanceFacility

AsbestosOisposaJArea

Closedi-!*lanc)!ill Area

LIMIT Q- REFUSE

E A S T Q U I N C Y A V E N U

Not to Scale

LEGEND:Landfill Boundary (Fence Line)

—•— Ground-water Compliance Bour jij. :.

..... Ground-water Action Boundary

Approximate Extent of Closed Landfill Arc i

The locations shown are appro:, mat,.

DEN GrapM.owry ROD/170

REVISEDFigure 11-2

GROUND-WATER COMPLIANCE BOUNDARYAND GROUND-WATER ACTION BOUNDARY

LOWRY EXPLANATION OFSIGNIFICANT DIFFERENCES

lowry landfill superfund site - explanation of … · file plan lortry landfill sup^efund site...

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