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Gulf State Utility - North Ryan Street Superfund SiteFirst Five-Year Review Report

September 20 10

Five-Year Review Report

First Five-Year Review Report

for

Gulf State Utility - North Ryan Street Superfund SiteLake Charles, Louisiana

September 2010

Region 6United States Environmental Protection Agency

Dallas, Texas


September 2010

Five-Year Review Memorandum

Gulf State Utility - North Ryan Street Superfund SiteCERCUS ID# LAD985169317

Lake Charles, Calcasieu Parish, Louisiana

Summary of First Five-Year Review Findings

This first FYR includes a review of relevant decision documents, implementationdocuments, remedy performance documents, operation and maintenance documents,legal documents and data obtained during routine monitoring activities. Thefollowing issues are noted:

1. Overall, insufficient data are available to confirm that MNA is an effectiveremedy for au 1, the groundwater au. Data collection needs are outlined in the setoffactors listed in Section 6.4 ofthe FYR report.

2. Lack of formal inspections, operation and maintenance (O&M) activities, andreporting for the cap at Exposed Tar Area.

3. Lack of formal inspections, O&M activities, and reporting for the cap on thesediment along the river.

4. Evaluate the need for an institutional control for the sediment cap; determinethe owner of the property on which the sediment cap is located and evaluate theadequate path forward for the remedy control.

5. Presence of heavy equipment stored on the Exposed Tar Area cap that may nothave been designed to withstand such stress.

6. Lack of signage informing that the facility is a Superfund Site and warningcitizens of residual contamination.

7. The mechanism for remediation of metals in groundwater is not described inSite documentation.

8. Evaluate the need whether arsenic should be a Site contaminant of concern(COC).

9. Costs have not been evaluated in the ROD for all on-going remedial activitiesat the Site.

10. Interconnectivity between the shallow and deep aquifer (particularly the 200foot zone), concern for which required sampling of supply wells, is not fully


September 2010

understood. Alternate sources may be present besides the GSU Site to account forearly detections of contaminants (some of which are GSU COCs) in supply wells.

II. Annual depiction of groundwater flow direction and tidal influence is notavailable; the degree to which groundwater discharges to surface water is notunderstood despite the finding that sediment samples from the Calcasieu River werefound impacted during the remedial investigation (RI).

12. Numerical ARARs for surface water have not been outlined in decisiondocuments, and the 2009 annual report only considered Federal standards.

13. Reference dose for naphthalene has changed since the preliminary remediationgoal (PRG) for naphthalene was developed for groundwater.

14. Risk assessment methodologies have changed, and in addition, the BaselineRisk Assessment (BRA) did not evaluate volatilization from groundwater or soil toindoor air.

15. Analytical methods may not be adequate to achieve detection limits forcomparison to cleanup standards such as benzo(a)pyrene; receive analytical results forsample prior to dilution so concentrations for all compounds in a sample can beevaluated against clean up goals.

16. The full extent of the residual contamination after the removal action wascompleted has not been delineated, as it was beyond the scope of the interim removalaction under the EE/CA. Ecological risk from residual contamination has not beenevaluated.

Actions Needed

Based on the issues identified, the following recommendations were made for theGSU Superfund Site:

I. Additional data collection is necessary to evaluate if MNA is an effectiveremedial action for OU I, including but not limited to: horizontal and vertical plumedelineation, calculation of constant rates of degradation, and estimation of time forremediation. After data collection, perform an evaluation of the MNA for all COCspresent at the site. If MNA is not effective, implement the contingency outlined inthe ROD, which may include development of alternative cleanup levels or theimplementation of a technical impracticability waiver. Evaluate if MNA is protectiveto ecological receptors.

2. Prepare an O&M plan for the cap constructed at the Exposed Tar Area, andafter EPA approval, implement the plan and prepare an O&M report.


September 20] 0

3. Prepare an O&M plan for the cap constructed over the sediments in CalcasieuRiver, and after EPA approval, implement the plan and prepare an O&M report.

4. Assess property ownership, evaluate how the integrity of the sediment cap willbe maintained over time, and determine how rcs will be implemented for thesediment cap.

5. Assess whether the Exposed Tar Area cap was built to withstand the load ofheavy equipment. Mark the location of the cap so O&M activities are facilitated andto avoid storage if design is not adequate.

6. Place signs regarding residual contamination.

7. Evaluate how barium, the only metal COC exceeding the MCL, will beremediated by the currently selected remedy; if the remedy is not effective, develop apath forward to address this COCo

8. ClarifY why arsenic, not a site coe, has been included in the suite of analytesfor the Site. Evaluate if it is a COC for the Site and if, so, evaluate if the groundwaterremedy will be effective in cleaning up this metal to the current MCL of 10micrograms per liter (llgIL).

9. Prepare cost evaluations for all activities to be performed in conjunction withthe Site remediation, including on-going O&M activities at OU 2, the soil OU.

10. Review all existing information to assess additional data collection needs tocomplete the hydrogeological characterization of the Site. This may be done inconjunction with the vertical delineation of groundwater impact and the assessment ofnon-aqueous phase liquid (NAPL) presence in the subsurface. Determine if a Siteimpact on the City of Lake Charles supply wells is possible. Research other sourcescontaining Site COCs that may have resulted in chemicals present in the supply wells.This can be an early indicator of other sources affecting this resource.

11. Review applicable standards for surface water.

12. Collect additional data to complete the understanding of thegroundwater/surface water interaction, and assess if surface water samples should becollected. These data will also be useful in understanding how the MNA is operatingat the Site.

13. Revise PRO for naphthalene.


September 2010

14. Review the risk assessment performed for the Site to ensure COCs arecaptured for all exposure pathways. The potential for vapor intrusion was notaddressed in the previous remedial investigation (RI). Volatiles detected in soil andgroundwater should be evaluated to address this issue. This needs to be completedprior to evaluation of remedial actions, in case additional factors need to be taken intoconsideration.

15. Review detection limits to ensure adequacy of methods. Request from theanalytical laboratory results of samples prior to dilution to obtain low detection limitsfor all compounds such that comparison to cleanup goals is possible.

16. Review post-removal data to determine if there is risk associated with residualpost-removal concentrations. Evaluate if there are ecological risks associated withresidual contamination.

Entergy is primarily responsible for implementing these actions. Upon approval ofthis five year review, an administrative copy of this document will be sent to Entergyand a conference call will be initiated by the EPA to discuss the findings of the report.

Determinations

The remedy for the GSU Superfund Site cannot be found to be protective ofhuman health and the environment in the long term at this time. The remedy for theGSU Superfund Site remains protective in the short term because, under the currentland use, there is no evidence of known current exposure to either groundwater or soilcontamination. In order to ensure both short- and long-term protectiveness, theperformance of the action items as described above and in this Five-Year ReviewReport must be appropriately addressed.

By:~sam...5u~el==c=o:::::l::e~m:::an=::;~~~=>-.2:=::~~--"-

Director, Superfu iVlslOnU.S. Environmental Protection Agency Region 6

3 .- 2-1-- f 0Date


September 2010

CONCURRENCES

Third Five-Year Review Report

for the

Gulf State Utility - North Ryan Street Superfund SiteCERCUS ID# LAD985169317

Valmiehael Leos, Re mal Project ManagerSuperfund LA I NM OK Section

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Cathy Gilmore, ChiefSuperfund LA / NM / OK Section

Donald Will' ams, Deputy AssociSuperfund Remedial Branch

Edwin M. Quinones,Att flee of Regional Counsel

Date

r j

Date

Date

FIRST FIVE-YEAR REVIEW REPORT

FOR THE

GULF STATES UTILITIES - NORTH RYAN STREET SUPERFUND SITELAKE CHARLES, LOUISIANA

September 2010

PREPARED FOR:

United States Environmental Protection AgencyRegion 6

Dallas, Texas

FIRST FIVE-YEAR REVIEW REPORTGulf States Utilities - North Ryan Street Superfund Site

EPA ID No. LAD985169317Lake Charles, Louisiana

This memorandum documents the U.S. Environmental Protection Agency's performance,determinations, and approval of the Gulf States Utilities - North Ryan Street Superfund Site's(Site) first five-year review under Section 121(c) of the Comprehensive EnvironmentalResponse, Compensation, and Liability Act, 42 United States Code § 9621 (c), as provided in theattached First Five-Year Review (FYR) Report.

Background

The First FYR for the Site was performed through a review of site documents and site-specificrequirements, site inspections performed on August 3, 2010, interviews with stakeholders, and areview of data collected at the Site during the review period. The Site is composed of twooperable units (OUs): au 1, for groundwater at the site and au 2, for soil.

The Record of Decision (ROD) for au I selected monitored natural attenuation (MNA) forgroundwater at the site. The remedy includes monitoring of drinking water supply wells andgroundwater wells installed at various depths within the alluvial aquifer. The purpose ofsampling the drinking water supply wells is to ensure that shallow contamination at the Site hasnot migrated to the City of Lake Charles water supply. In addition, institutional controls wereplaced in order to prevent human and ecological exposure to contaminated groundwater. At au2, an interim removal action consisted of excavation of contaminated soils (including theExposed Tar Area and the West Ditch) (to a depth of no less than 2.5 feet below ground surface),dredging of contaminated sediments (to a depth not specified), thermal treatment and/or disposalof excavated/dredged soil and sediment, in-situ thermal treatment of soil in an exposed tar area,and placement of caps (thickness not specified) over the residual contamination at the exposedtar area and river sediments. The ROD for au 2 called for no further action at this au;however, inspections and maintenance ofthe caps were to be performed and a restrictivecovenant on soil use was supposed to be implemented to limit the future use of the area wherethe caps Were installed. Based on the Final Ecological Risk Assessment, ecological risks wereonly associated with the Calcasieu River sediments and cypress wetland; however, the cypresswetland was eliminated as an area of concern for the Site.

No community concerns were identified during the review.

Summary of First Five-Year Review Findings

This first FYR includes a review of relevant decision documents, implementation documents,remedy performance documents, operation and maintenance documents, legal documents anddata obtained during routine monitoring activities. The following issues are noted:

This section describes issues associated with the Site that were identified during the First Fiveyear review:

1. Overall, insufficient data are available to confirm that MNA is an effective remedy forOU 1, the groundwater OU. Data collection needs are outlined in the set of factors listedin Section 6.4 of the FYR report.

2. Lack of formal inspections, operation and maintenance (O&M) activities, and reporting.for the cap at Exposed Tar Area.

3. Lack of formal inspections, O&M activities, and reporting for the cap on the sedimentalong the river.

4. Evaluate the need for an institutional control for the sediment cap; determine the ownerof the property on which the sediment cap is located and evaluate the adequate pathforward for the remedy control.

5. Presence of heavy equipment stored on the Exposed Tar Area cap that may not have beendesigned to withstand such stress.

6. Lack of signage informing that the facility is a Superfund Site and warning citizens ofresidual contamination.

7. The mechanism for remediation of metals in groundwater is not described in Sitedocumentation.

8. Evaluate if arsenic should be a Site contaminant of concern (COC) or is naturallyoccurnng.

9. Costs have not been evaluated in the ROD for all on-going remedial activities at the Site.

10. Interconnectivity between the shallow and deep aquifer (particularly the 200;.,foot zone),concern for which required sampling of supply wells, is not fully understood. Alternatesources may be present besides the GSU Site to account for early detections ofcontaminants (some of which are GSU COCs) in supply wells.

11. Annual depiction of groundwater flow direction and tidal influence is not available; thedegree to which groundwater discharges to surface water is not understood despite thefinding that sediment samples from the CalcasieuRiver were found impacted during theremedial investigation (RI).

12. Numerical ARARsfor surface water have not been outlined in decision documents, andthe 2009 annual report only considered Federal standards.

13. Reference dose for naphthalene has changed since the preliminary remediation goal(PRG) for naphthalene was developed for groundwater.

14. Risk assessment methodologies have changed, and in addition, the Baseline RiskAssessment (BRA) did not evaluate volatilization from groundwater or soil to indoor air.

2

15. Analytical methods may not be adequate to achieve detection limits for comparison tocleanup standards such as benzo(a)pyrene; receive analytical results for sample prior todilution so concentrations for all compounds in a sample can be evaluated against cleanup goals.

16. The full extent of the residual contamination after the removal action was completed hasnot been delineated, as it was beyond the scope of the interim removal action under theEE/CA. Ecological risk from residual contamination has not been evaluated.

Actions Needed

Based on the issues identified, the following recommendations were made for the GSUSuperfund Site:

1. Additional data collection is necessary to evaluate if MNA is an effective remedial actionfor OU 1, including but not limited to: horizontal and vertical plume delineation,calculation of constant rates of degradation, and estimation of time for remediation.After data collection, perform an evaluation of the MNA for all COCs present at the site.

IfMNA is not effective, implement the contingency outlined in the ROD, which mayinclude development of alternative cleanup levels or the implementation of a technicalimpracticability waiver. Evaluate ifMNA is protective to ecological receptors.

2. Prepare an O&M plan for the cap constructed at the Exposed Tar Area, and after EPAapproval, implement the plan and prepare an O&M report.

3. Prepare an O&M plan for the cap constructed over the sediments in Calcasieu River, andafter EPA approval, implement the plan and prepare an O&M report.

4. Assess property ownership, evaluate how the integrity of the sediment cap will bemaintained over time, and determine how ICs will be implemented for the sediment cap.

5. Assess whether the Exposed Tar Area cap was built to withstand the load of heavyequipment. Mark the location of the cap so O&M activities are facilitated and to avoidstorage if design is not adequate.


7. Evaluate how barium, the only metal COC exceeding the MCL, will be remediated by thecurrently selected remedy; if the remedy is not effective, develop a path forward toaddress this COC.

3

8. Clarify why arsenic, not a site COC, has been included in the suite of analytes for the

Site. Evaluate if it is a COC for the Site and if, so, evaluate if the groundwater remedywill be effective in cleaning up this metal to the current MCL of 10 micrograms perliter (llgIL).

9. Prepare cost evaluations for all activities. to be performed in conjunction with the Siteremediation, including on-going O&M activities at OU 2, the soil OU.

10. Review all existing information to assess additional data collection needs to complete thehydrogeological characterization of the Site. This may be done in conjunction with thevertical delineation of groundwater impact and the assessment of non-aqueous phaseliquid (NAPL) presence in the subsurface. Determine if a Site impact on the City of Lake

Charles supply wells is possible. Research other sources containing Site COCs that mayhave resulted in chemicals present in the supply wells. This can be an early indicator ofother sources affecting this resource.

11. Review applicable standards for surface water.

12. Collect additional data to complete the understanding ofthe groundwater/surface waterinteraction, and assess if surface water samples should be collected. These data will alsobe useful in understanding how the MNA is operating at the Site.

13. Revise PRG for naphthalene.

14. Review the risk assessment performed for the Site to ensure COCs are captured for allexposure pathways. The potential for vapor intrusion was not addressed in the previousremedial investigation (Rl). Volatiles detected in soil and groundwater should be

evaluated to address this issue. This needs to be completed prior to evaluation ofremedial actions, in case additional factors need to be taken into consideration.

15. Review detection limits to ensure adequacy of methods. Request from the analytical

laboratory results of samples prior to dilution to obtain low detection limits for allcompounds such that comparison to cleanup goals is possible.

16. Review post-removal data to determine if there is risk associated with residual postremoval concentrations. Evaluate if there are ecological risks associated.with residual

contamination.

4

Determinations

The remedy for the GSU Superfund Site cannot be found to be protective of human healthand the environment in the long term at this time. The remedy for the GSU Superfund Siteremains protective in the short term because, under the current land use, there is no evidenceof known current exposure to either groundwater or soil contamination. In order to ensureboth short- and long-term protectiveness, the performance of the action items as describedabove and in this Five-Year Review Report must be appropriately addressed.·

BY:~~v Samuel Colem~n, P.E~ coDirector, Super'ftm: .Divisionu.S. EPA Region 6

5

Date

CONCURRENCES:

FIRST FIVE-YEAR REVIEW REPORTGULF STATES UTILITIES ~ NORTH RYAN STREET SUPERFUND SITE

EPA ID No. LAD985169317

almlchael Leo, Rem dia roject ManagerSuperfund LA / NM / Section

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Donald Williams, Deputy Associate DirectorSuperfund Remedial Branch

Mark Peycke, C iefSuperfund Branch, Office of Regional Counsel

Date

q-vt-l ()Date

Attachments

I Documents Reviewed2 Site Inspection Checklist3 Site Survey Fonns4 Site Inspection Photographs5 Public Notice for Initiation of Five-Year Review6 Institutional Control- Covenant for Restrictions on Use7 Original ARARs

11

Number

12

Number

12345

LIST OF FIGURES

Site Location MapSite Layout Map

LIST OF TABLES

Cluonology of Site EventsAnnual Operation and Maintenance CostsComparison of ARARs to Current Groundwater StandardsCurrent Federal Surface Water StandardsRecommendations and Follow-up Actions

iii

Jlg/L1,2-DCA

ACLAFCEEAOCARARATSDR

B&VB(a)PbgsBRABTEX

CERCLACFRCOC

DNAPL

EAEE/CAEntergyEPAERAER-M

FFSFSFSPFYR

GSU

HHRAHI

IC

LDEQ

MARaSMCLmg/kg

LIST OF ACRONYMS AND ABBREVIATIONS

micrograms per liter1,2-dichloroethane

Alternate Control LimitAir Force Center for Enviromnental ExcellenceAdministrative Order on ConsentApplicable or Relevant and Appropriate RequirementAgency for Toxic Substances and Disease Registry

Black and Veatchbenzo(a)pyrenebelow ground surfaceBaseline Risk Assessmentbenzene, toluene, ethylbenzene, and xylenes

Comprehensive Enviromnental Response, Compensation, and Liability ActCode of Federal Regulationscontaminant of concern

dense non-aqueous phase liquid

EA Engineering, Science, and Technology, Inc.Engineering Evaluation/Cost AnalysisEntergy Gulf States, Inc.u.S. Enviromnental Protection Agency Region 6Ecological Risk AssessmentEffects Range-Medium

focused feasibility studyfeasibility studyfield sampling planfive-year review

Gulf States Utilities

Human Health Risk Assessmenthazard index

institutional control

Louisiana Department of Enviromnental Quality

Monitoring and Remediation Optimization Systemmaximum contaminant levelmilligrams per kilogram

IV

mg/LMNA

NCPNOAANPL

O&MOSWEROU

PAHsPCBsPRGPRPPRSC

QAPP

RARAPRAORCRARIDRIROD

SARASDWASiteSSI

TBC

UAO

VOC

WQC

milligrams per litermonitored natural attenuation

National Oil and Hazardous Substances Pollution Contingency PlanNational Oceanic and Atmospheric AdministrationNational Priorities List

operation and maintenanceOffice of Solid Waste and Emergency Responseoperable unit

polycyclic aromatic hydrocarbonspolychlorinated biphenylspreliminary remediation goalpotentially responsible partyPost-Removal Site Control Plan

Quality Assurance Project Plan

remedial actionRemedial Action Planremedial action objectiveResource Conservation and Recovery Actreference doseremedial investigationRecord of Decision

Superfund Amendments and Reauthorization ActSafe Drinking Water ActGulf States Utilities - North Ryan Street Superfund Sitescreening site inspection

to-becconsidered

Unilateral Administrative Order

volatile organic compound

water quality criterion

v

EXECUTIVE SUMMARY

The U.s. Environmental Protection Agency Region 6 (EPA) has conducted the First Five-Year

Review (FYR) of the remedial actions (RAs) implemented at the Gulf States Utilities (GSU)

North Ryan Street Superfund Site (Site), located on the Ca1casieu River, approximately 0.5 miles

north of Interstate 10 and along North Ryan Street in Lake Charles, Louisiana. The purpose of

this FYR was to determine whether the selected remedy for the Site continues to protect human

health and the environment. This review was conducted from August to September 2010, and its

findings and conclusions are documented in this report. This is the first FYR for the Site.

Several documents were reviewed as part of this FYR: the Remedial Investigation (RI) and

Feasibility Study (FS) reports, an action memorandum and Engineering Evaluation/Cost

Analysis (EE/CA) for a non-time critical removal action, removal action reports, Records of

Decision (RODs) for OU 1 (EPA 2000a) and OU 2 (EPA 2004b), the Final Close Out Report,

the Public Health Assessment for the Site (Agency for Toxic Substances and Disease Registry

(ATSDR] 2006), and annual groundwater monitoring reports for 2006,2007,2008, and 2009

(Black and Veatch [B&V] 2007, 2008, 2009, 2010).

The Site was defined by the EPA in the 2000 ROD (EPA 2000a) to occupy approximately

6 acres, which covers the footprint of the wetlands where Site wastes were initially dumped from

1932 through 1980. These wastes were the source of contamination that defined the areal extent

where remediation was required. The first Administrative Order of Consent (AOC) was issued

for the Site in 1997 (EPA 1997). Under this AOC, Entergy Gulf States, Inc. (Entergy) (formerly

Gulf States Utilities), who entered this order voluntarily with EPA, was required to perform an

RIlFS and to develop an EE/CA for the Site (EPA 1997). In addition, Entergy was to reimburse

the United States for all past and future response costs paid or to be incurred in connection with

the Site, as provided in this AOC.

The EE/CA was completed in 1998 (B&V 1998) and was followed in 1999 by an Action

Memorandum (EPA 1999a) and the completed RIIFS (B&V I999c). Subsequent to the issue of

the Action Memorandum, EPA issued another AOC with Entergy to perform the non-time

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critical removal action (the transmittal letter for this AOC notes that the effective date was

October 25,1999 [EPA 1999b]).

The specific objectives of the removal action as specified in the Action Memorandum addressed

the following areas (which later on were addressed as au 2):

• On-site contaminated soil areas, known as the exposed tar and storm sewer areas

o Limit the exposure of workers and visitors to chemicals of concern in this area ator near the surface

o Reduce the amount of heavily contaminated source material to minimize thecontinued threat of chemical migration from this material into the shallowgroundwater and surrounding soils

• Calcasieu River sediment at the storm water discharge point

o Reduce the direct ecological impact of contaminated sediment by reducingpolynuclear aromatic hydrocarbons (PAHs) to below action level values

o Minimize the potential direct exposure of recreational users and indirect exposurefrom fish and shellfish consumption

o Limit migration of chemicals of concern in the Calcasieu River sediment awayfrom the point of elevated contaminant levels.

The removal actions were performed between 2000 and 2003 and included dredging, dewatering

and disposal of sediment from the Calcasieu River, and excavation of storm sewer piping,

bedding soil, and sediments from the west drainage ditch. Removal activities also included

thermal treatment and/or disposal of soils and sediments, and in-situ thermal treatment of soil in

the area where tar was exposed on the ground surface (EPA 2006).

Excavation was also performed in the exposed tar area (depth of excavation ranged from 2.5 to

6 feet below ground surface), and a temporary cover consisting of a compacted aggregate base

was placed over the excavated area and graded to allow drainage away from the area. Some

areas with sediment concentrations exceeding the removal action goals could not be additionally

dredged due to their proximity to a sunken World War II ship carrying Bunker C, a heavy fuel

oil, and/or the reach of the crane's boom (EPA 2004b). Along the shoreline, a cap (e.g.,

revetment) was placed over the river sediment to provide stability and improve the aesthetic

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appeal of the shoreline. In addition, a sediment cover, installed as an extension to the geotextile

fabric and concrete mattress, was placed in the Calcasieu River to isolate and cover any residual

contamination in the storm sewer outfall area.

The final activity for the Site removal action was the installation of a permanent, engineered cap

over the exposed tar area excavation. The cap consisted of geogrid, geotextile, and

geomembrane components, was constructed to a height of approximately three (3) feet above the

ground surface, and was domed to allow surface runoff. The removal action was completed in

February 2003 and culminated in an OU 2 ROD specifying No Further Action other than

institutional controls (ICs) with respect to access, and cap and revetment maintenance. These

rcs subject OU 2 to FYR, despite completion of active remediation in 2003.

In 2000, EPA issued a ROD (EPA 2000a) for OU I, the groundwater OU. The remedial action

objectives (RAOs) for this selected remedy are as follows:

• Maintain site property for commercial/industrial use only

• Prevent exposure to site contaminated groundwater above acceptable risk levels forpotential receptors

• Restore the site groundwater to human health-based standards following remediation ofthe exposed tar area

• Assure that no migration of contaminants from the groundwater is occurring whereby theimpact causes the surface water to exceed regulatory and/or risk-based standards relatingto human health and the environment.

The selected remedy for OU I included the following:

• Monitored natural attenuation of groundwater, including sampling groundwater wellsinstalled to depths within the alluvial aquifer in order to confirm a decrease incontamination over time

• Monitoring surface water and drinking water supply wells to assure that contaminants donot exceed any regulatory or health based risk levels at points-of-exposure

• rcs which require that Entergy file a notice of groundwater use restrictions and placethem in the property records for the Site, in order to prevent human exposure tocontaminated groundwater

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• As long as contaminants exceed standards, operation and maintenance (O&M).

The 2000 ROD noted that "a subsequent remedial action, to be named OU2, is planned to

address any residual source (soil/sediment) contamination remaining after both the source

removal and ground water remedial actions are completed. The response action in this ROD will

be consistent with the final action selectedfor this site" (EPA 2000a).

In 2004, EPA issued a ROD addressing OU 2 (EPA 2004b). This ROD stated that the "site

removal action addressed contaminated soil, sediment, and source material constituting

principal threat wastes and residual low-level threat wastes; therefore, because previous

responses at the Site andfor OU 2 eliminated the need to conductjUrther remedial action, the

selected remedial action is No Further Action Necessary, for OU 2[...], the Soil Operable Unit.

This remedial action is compatible with the remedy selectedfor OU I, the Ground Water Ou,

and will be the final remedial action for this Site." However, this remedial action left low-level

threat wastes onsite and the ROD required operation and maintenance activities including but not

limited to: Site maintenance, monitoring, and compliance with the restrictions of the IC to

ensure that no unacceptable exposures to risks posed by the Site or OU 2 occur in the future. As

a consequence, OU 2 is still included in this FYR.

A UAO was issued in July 2005 for the implementation of the OU 1 remedy identified in the

Ground Water Remedial Action Plan (RAP) (B&V 2003b) and to implement ICs for this

operable unit (EPA 2005b).

Hazardous substances remain at the Site in soil and sediments above health-based levels after

completion of the removal action and are contained by a cap; ICs are in place to restrict the use

of the Site for industrial use and prohibit excavation of soil. Hazardous substances are currently

present in groundwater and are subject to monitored natural attenuation. Because waste has been

capped and ICs are in place, the EPA must conduct a statutory review every five years, pursuant

to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)

Section 121(c) and as provided in Office of Solid Waste and Emergency Response (OSWER)

Directive 9355.7-02, Structure and Components of Five-Year Reviews, 23 May 1991; OSWER

Directive 9355.7-02A, Supplemental Five-Year Review Guidance, 26 July 1994; Second

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Supplemental Five-Year Review Guidance, 21 December 1996; and OSWER Directive 9355.7

03B-P Draft Comprehensive Five-Year Review Guidance, October 1999.

The FYR consisted of the following activities: review of relevant documents, interviews with

local water utility company representative, representatives of the maintenance contractors, and a

five-year review site inspection. EPA completed the first FYR inspection of the Site on

3 August 2010 (documented herein). The inspection verified that the containment remedy was in

place and appeared to be functioning as designed; monitoring of the Site groundwater wells was

taking place at the time of the visit. The capped area at the Entergy facility is currently used for

storage of heavy equipment, and it is uncertain if the design ofthe cap is adequate for this use.

One other requirement of a FYR is to determine if there are any new requirements that may

pertain to the Site. The reference dose for naphthalene has changed, so the preliminary

remediation goals for this compound needs to be reevaluated. Also, risk assessment

methodologies have changed (e.g. dermal toxicity adaptation and vapor intrusion), so the risk

assessment performed for the Site should be reviewed. No other newly promulgated

requirements that pertain to the Site were identified.

Since this is a statutory site that requires ongoing five-year reviews, the next review will be

conducted within five years of the completion of this FYR report. This review included the

general activities performed since the 2005 UAO was signed through August 20 Io. The

following issues were noted:

1. Overall, insufficient data are available to confirm that MNA is an effective remedy forOU 1, the groundwater OU. Data collection needs are outlined in the set of factors listedin Section 6.4 of the FYR report.

2. Lack offormal inspections, operation and maintenance (O&M) activities, and reportingfor the cap at Exposed Tar Area.

3. Lack of formal inspections, O&M activities, and reporting for the cap on the sedimentalong the river.

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4. Evaluate the need for an institutional control for the sediment cap; determine the ownerofthe property on which the sediment cap is located and evaluate the adequate pathforward for the remedy control.

5. Presence of heavy equipment stored on the Exposed Tar Area cap that may not have beendesigned to withstand such stress.



8. Evaluate if arsenic should be a Site contaminant of concern (COC) or is naturallyoccurring.

9. Costs have not been evaluated in the ROD for allan-going remedial activities at the Site.

10. Interconnectivity between the shallow and deep aquifer (particularly the 200-foot zone),concern for which required sampling of supply wells, is not fully understood. Alternatesources may be present besides the GSU Site to account for early detections ofcontaminants (some of which are GSU COCs) in supply wells.

11. Annual depiction of groundwater flow direction and tidal influence is not available; thedegree to which groundwater discharges to surface water is not understood despite thefinding that sediment samples from the Ca1casieu River were found impacted during theRI.

12. Numerical ARARs for surface water have not been outlined in decision documents, andthe 2009 annual report only considered Federal standards.

13. Reference dose for naphthalene has changed since the PRG for naphthalene wasdeveloped for groundwater.

14. Risk assessment methodologies have changed, and in addition, the BRA did not evaluatevolatilization from groundwater or soil to indoor air.

15. Analytical methods may not be adequate to achieve detection limits for comparison tocleanup standards such as benzo(a)pyrene; receive analytical results for sample prior todilution so concentrations for all compounds in a sample can be evaluated against cleanup goals.


ES-6

The following actions are needed in response to these issues:

1. Additional data collection is necessary to evaluate if MNA is an effective remedial actionfor OU 1, including but not limited to: horizontal and vertical plume delineation,calculation of constant rates of degradation, and estimation of time for remediation.After data collection, perform an evaluation of the MNA for all COCs present at the site.IfMNA is not effective, implement the contingency outlined in the ROD, which mayinclude development of alternative cleanup levels or the implementation of a technicalimpracticability waiver. Evaluate ifMNA is protective to ecological receptors.

2. Prepare an O&M plan for the cap constructed at the Exposed Tar Area, and after EPAapproval, implement the plan and prepare O&M report.

3. Prepare an O&M plan for the cap constructed over the sediments inCalcasieu River, andafter EPA approval, implement the plan and prepare O&M report.

4. Assess property ownership, evaluate how the integrity of the sediment cap will bemaintained over time, and determine how ICs will be implemented for the sediment cap.

5. Assess whether the Exposed Tar Area cap was built to withstand the load of heavyequipment. Mark the location of the cap so O&M activities are facilitated and to avoidstorage if design is not adequate.


7. Evaluate how barium, the only metal COC exceeding the MCL will be remediated by thecurrently selected remedy; if the remedy is not effective, develop a path forward toaddress this COC..

8. ClarifY why arsenic, not a site COC, has been included in the suite of analytes for theSite. Evaluate if it is a COC for the Site and if, so, evaluate if the groundwater remedywill be effective in cleaning up this metal to the current MCL of 10 micrograms perliter (Ilg/L).

9. Prepare cost evaluations for all activities to be performed in conjunction with the Siteremediation, including on-going O&M activities at OU 2, the soil OU.

10. Review all existing information to assess additi()nal data collection needs to complete thehydrogeological characterization of the Site. This may be done in conjunction with thevertical delineation of groundwater impact and the assessment ofNAPL presence in thesubsurface. Determine if a Site impact on the City of Lake Charles supply wells ispossible. Research other sources containing Site COCs that may have resulted in

chemicals present in the supply wells. This can be an early indicator of other sourcesaffecting this resource.

II. Review applicable standards for surface water.

12. Collect additional data to complete the understanding of the groundwater/surface waterinteraction, and assess if surface water samples should be collected. These data will alsobe useful in understanding how the MNA is operating at the Site.


14. Review the risk assessment performed for the Site to ensure COCs are captured for allexposure pathways. This needs to be completed prior to evaluation of remedial actions,in case additional factors need to be taken into consideration.

15. Review detection limits to ensure adequacy of methods. Request from the analyticallaboratory results of samples prior to dilution to obtain low detection limits for allcompounds such that comparison to cleanup goals is possible.

16. Review post-removal data to determine if there is risk associated with residual postremoval concentrations. Evaluate ifthere are ecological risks associated with residualcontamination.

Entergy is primarily responsible for implementing these actions. Upon approval of this five

year review, an administrative copy of this document will be sent to Entergy and a

conference call will be initiated by the EPA to discuss the findings of the report.

The remedy for the GSU Superfund Site cannot be found to be protective of human health

and the environment in the long term at this time. The remedy for the GSU Superfund Site

remains protective in the short term because, under the current land use, there is no evidence

of known current exposure to either groundwater or soil contamination. In order to ensure

both short- and long-term protectiveness, the performance ofthe action items as described

above and in this Five-Year Review Report must be appropriately addressed.

ES-8

'II

Five-Year Review Summary Form

SITE IDENTIFICATION

Site Name (from Waste LAN): Gulf States Utilities - North Ryan Street Superfund Site

EPA ID (from Waste LAN): LAD985169317

NFL Status: 0 Final 0 Deleted [gJ Other (specify) Not Listed

Remediation Status (choose all that apply): 0 Under Construction 0 Operating

[gJ Complete

Multiple OUs?* [gJ YES 0 NO Construction Completion Date: February 2003

Has site been put into reuse? [gJ YES ONO

REVIEW STATUS

Reviewing Agency: [gJ EPA 0 State 0 Tribe 0 Other Federal Agency

Author Name: Mr. Valmichael Leos

Author Title: Remedial Project Manager

Review Period:** September 2005-August 2010

Date(s) of Site Inspection: 3 August 2010

Author Affiliation: EPA Region 6

Type of Review: [gJ Statutory

o Policy 0 Post-SARA 0 Pre-SARA 0 NPL-Removalonly

o Non-NPL Remedial Action Site 0 NPL Stateffribe-Iead

o Regional Discretion

Review Number: [gJ 1 (first) 0 2 (second) 0 3 (third) 0 Other (specify)

Triggering Action:

o Actual RA Onsite Construction at OU 0 Actual RA Start

o Construction Completion 0 Previous Five-Year Review Report

[gJ Other (specify) Unilateral Administrative Order to implement the groundwater Record ofDecision

Triggering Action Date (from Waste LAN): September 2005

Due Date (Five Years After Triggering Action Date): September 2010

*au refers to operable unit.

** The review periodrefers to the period during which the five-year review was conducted.

ES-9

Five-Year Review Summary Form (Continued)

Issues:The following issues associated with the Site were identified during the First FYR:

I. Overall, insufficient data are available to confinn that MNA is an effective remedy for OU I, thegroundwater OU. Data collection needs are outlined in the set of factors listed in Section 6.4 ofthe FYR report.

2. Lack offonnal inspections, operation and maintenance (O&M) activities, and reporting for the capat Exposed Tar Area.

3. Lack of fonnal inspections, O&M activities, and reporting for the cap on the sediment along theriver.

4. Evaluate the need for an institutional control for the sediment cap; detennine the owner of theproperty on which the sediment cap is located and evaluate the adequate path forward for theremedy control.

5. Presence ofheavy equipment stored on the Exposed Tar Area cap that may not have been designedto withstand such stress.

6. Lack of signage infonning that the facility is a Superfund Site and warning citizens of residualcontamination.

7. The mechanism for remediation ofmetals in groundwater is not described in Site documentation.

8. Evaluate if arsenic should be a Site contaminant of concern (COC) or is naturally occurring.


10. Interconnectivity between the shallow and deep aquifer (particularly the 200-foot zone), concernfor which required sampling of supply wells, is not fully understood. Alternate sources may bepresent besides the GSU Site to account for early detections ofcontaminants (some ofwhich areGSU COCs) in supply wells.

II. Annual depiction of groundwater flow direction and tidal influence is not available; the degree towhich groundwater discharges to surface water is not understood despite the finding that sedimentsamples from Calcasieu River were found impacted during the RI.

12. Numerical ARARs for surface water have not been outlined in decision documents and the 2009annual report only considered Federal standards.

13. Reference dose for naphthalene has changed since the PRG for naphthalene was developed forgroundwater.


15. Analytical methods may not be adequate to achieve detection limits for comparison to cleanupstandards such as benzo(a)pyrene; receive analytical results for sample prior to dilution soconcentrations for all compounds in a sample can be evaluated against clean up goals.

16. The full extent ofthe residual contamination after the removal action was completed has not beendelineated, as it was beyond the scope of the interim removal action under the EE/CA. Ecologicalrisk from residual contamination has not been evaluated.

ES-IO

Recommendations and Follow-up Actions:

I. Additional data collection is necessary to evaluate ifMNA is an effective remedial action forOU I, including but not limited to: horizontal and vertical plume delineation, calculation ofconstant rates of degradation, and estimation of time for remediation. After data collection,perform an evaluation of the MNA for all COCs present at the site. If MNA is not effective,implement the contingency outlined in the ROD, which may include development of alternativecleanup levels or the implementation of a technical impracticability waiver. Evaluate if MNA isprotective to ecological receptors.

2. Prepare an O&M plan for the cap constructed at the Exposed Tar Area, and after EPA approval,implement the plan and prepare an O&M report.

3. Prepare an O&M plan for the cap constructed over the sediments in Calcasieu River, and afterEPA approval, implement the plan and prepare an O&M report.

4. Assess property ownership, evaluate how the integrity of the sediment cap will be maintained overtime, and determine how ICs will be implemented for the sediment cap.

5. Assess whether the Exposed Tar Area cap over the Exposed Tar Area was built to withstand theload of heavy equipment. Mark the location ofthe cap so O&M activities are facilitated and toavoid storage if design is not adequate.


7. Evaluate how barium, the only metal COC exceeding MCL, will be remediated by the currentlyselected remedy; if the remedy is not effective, develop a path forward to address this COCo

8. Clarify why arsenic, not a site COC, has been included in the suite of analytes for the Site.Evaluate if it is a COC for the Site and ·if, so, evaluate if the groundwater remedy will be effectivein cleaning up this metal to the current MCL of 10 1!g!L.

9. Prepare cost evaluations for all activities to be performed in conjunction with the Site remediation,including on-going O&M activities at OU 2, the soil OU.

10. Review all existing information to assess additional data collection needs to complete thehydrogeological characterization of the Site. This may be done in conjunction with the verticaldelineation of groundwater impact and the assessment ofNAPL presence in the subsurface.Determine ifa Site impact on the City of Lake Charles supply wells is possible. Research othersources containing Site COCs that may have resulted in chemicals present in the supply wells.This can be an early indicator ofother sources affecting this resource.

II. Review applicable standards for surface water.

12. Collect additional data to complete the understanding of the groundwater/surface waterinteraction, and assess if surface water samples should be collected. These data will also be usefulin understanding how the MNA is operating at the Site.


14. Review the risk assessment performed for the Site to ensure COCs are captured for all exposurepathways. This needs to be completed prior to evaluation of remedial actions, in case additionalfactors need to be taken into consideration.

15. Review detection limits to ensure adequacy of methods. Request from the analytical laboratoryresults of samples prior to dilution to obtain low detection limits for all compounds such thatcomparison to cleanup goals is possible.

ES-ll

16. Review post-removal data to detennine if there is risk associated with residual post-removalconcentrations. Evaluate if there are ecological risks associated with residual contamination.

Protectiveness Statement

The Temedy for the GSU Superfund Site remains protective because, under the current land use, there is noevidence of known current exposure to either groundwater or soil contamination. However, in order forthe remedy to remain protective, the actions recommended need to be implemented.

ES-12

1.0 INTRODUCTION

The U.S. Environmental Protection Agency Region 6 (EPA), with assistance from EA

Engineering, Science, and Technology, Inc. (EA), and in coordination with the Louisiana

Department for Environmental Quality (LDEQ) has conducted the first five-year review (FYR)

of the remedial actions (RAs) implemented at the Gulf States Utilities (GSU) - North Ryan Street

Superfund Site (Site) in Lake Charles, Louisiana. The purpose of a FYR is to determine whether

the remedy at a site remains protective of human health and the environment and to document

the methods, findings, and conclusions of the FYR process in a report. The report will identifY

issues found during each review, if any, and make recommendations to address the issues. This

first FYR report documents the results of the review for the Site, conducted in accordance with

EPA guidance (EPA 2001) on FYRs. As of February 2010, the Site has not been listed on the

National Priorities List (NPL) (EPA 2010). Of note is the fact that in the past, this Site was

referred to as either the Gulf States Utilities or North Ryan Street Site. For ease of reading, the

nomenclature GSU is used throughout this FYR report.

The FYR process is required by federal statute. The EPA must implement FYRs consistent with

the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and

the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). CERCLA

Section 121(c), 42 United States Code § 9621 (c), states the following:

"Ifthe President selects a remedial action that results in any hazardous

substances, pollutants, or contaminants remaining at the site, the President shall

review such remedial action no less often than each jive years after the initiation

ofsuch remedial action to assure that human health and the environment are

beingprotected by the remedial action being implemented."

NCP Section 300.430(f)(4)(ii) states the following:

"Ifa remedial action is selected that results in hazardous substances, pollutants,

or contaminants remaining at the site above levels that allow for unlimited use

1

and unrestricted exposure, the lead agency shall review such action no less often

than every five years after the initiation ofthe selected remedial action."

Because hazardous substances, pollutants, or contaminants remain at the Site above levels that

allow for unlimited use and unrestricted exposure, a statutory FYR is required.

There are two operable units (OUs) at the Site: au I for groundwater and au 2 for soil. The

Site was divided for the first time into OUs when the au I FS was prepared for groundwater

remedy evaluation (Black and Veatch [B&V] 1999c). Shortly thereafter, in 2000, a ROD was

signed to select a remedy for au 1 (EPA 2000a). The OU 1 ROD was followed in 2004 by the

OU-2 ROD, which addresses the soil (EPA 2004b). Ultimately, the implementation of the au I

ROD was outlined in the July 2005 Unilateral Administrative Order (UAO) (EPA 2005b).

This first FYR spans the period from July 2005 through August 2010; its methods, findings,

conclusions, and recommendations based on documents available in this time period are

documented in this report.

This report documents the FYR for the Site by providing the following information: site

chronology (Section 2.0); background information (Section 3.0); an overview of the RAs

(Section 4.0); progress since the previous FYR (which in this case provides no evaluation since

this is the first FYR performed for the Site) (Section 5.0); a discussion of the FYR process,

activities and findings (Section 6.0); technical assessment of the Site (Section 7.0); institutional

controls (lCs) (Section 8.0); issues noted with respect to RAs (Section 9.0); recommendations

and follow-up actions (Section 10.0); protectiveness statement (Section 11.0); and discussion of

the next review (Section 12.0). Attachment 1 provides a list of documents reviewed,

Attachment 2 provides the Site inspection checklist, Attachment 3 provides Site survey forms,

Attachment 4 provides the Site inspection photographs, Attachment 5 provides a copy of the

Public Notice for Initiation of Five-Year Review, and Attachment 6 contains the IC Covenant for

Restriction of Use.

2

2.0 SITE CHRONOLOGY

A chronology of events for the Site is provided in Table 1. Additional historical infonnation is

available online at http://www.epa.govlregion6/6sf/pdffiles/0603977.pdf(EPA 2010).

3.0 BACKGROUND

This section discusses the Site's physical characteristics, land and resource use near the Site,

history of Site contamination, initial response to the Site, and basis for the response.

3.1 PHYSICAL CHARACTERISTICS

The Site is located on the Calcasieu River, approximately 0.5 miles north of Interstate 10 and

along North Ryan Street in Lake Charles, Louisiana (Figure 1). The Site was originally a

manufactured gas plant on the south bank ofthe Calcasieu River, and is currently operated as the

Lake Charles Division Service Center of Entergy Gulf States, Inc. (Entergy) (EPA 20 I0).

Historical Site operations utilized a six-acre wetlands area for landfill activities.

Regional Hydrogeology

Fresh water aquifers underlying the Lake Charles region include undifferentiated shallow

alluvial aquifers and the Chicot Aquifer, while groundwater below the Chicot Aquifer is

predominantly salt water. The shallow alluvial aquifers are located along the Calcasieu River

and its tributaries in the area. These aquifers consist of fine sand with thin lenses of coarser sand

and varying amounts of silt and clay deposited by the river system. The alluvial aquifers are

capable of locally producing low to high amounts of groundwater, and are recharged by

precipitation and direct hydraulic connection to the Calcasieu River. Discharge from the alluvial

aquifers occurs to the Calcasieu River and interconnecting tributaries, and to a lesser degree by

leakage into the underlying silts and clays (EPA 2000a).

3

The primary freshwater potable aquifer in the Lake Charles region is the Chicot Aquifer. The

Chicot Aquifer contains three sand beds separated by clay and silt, and these sand beds are the

principal water bearing units in the Lake Charles area. The three sand beds are known, in

descending order, as the 200-foot, 500-foot, and 700-foot sands, which basically correspond with

their depths below ground surface (EPA 2000a).

The alluvial aquifers near the site are generally separated from the underlying Chicot Aquifer by

confining silt and clay beds of the Prairie Formation. However, the alluvial aquifers are

interconnected to the Chicot Aquifer in northern Calcasieu Parish, where the Chicot Aquifer

crops out.

Water discharged or pumped from the Chicot Aquifer is used for irrigation, industrial, and

municipal drinking water purposes in the Lake Charles area. Six operating public supply wells

are in close proximity to the site, mostly on the adjacent property at the water treatment plant

located directly to the southwest (about 14 other public supply wells have either been plugged or

destroyed). These wells are screened at depth in the regional500-foot and 700-foot sands. The

water pumped from these wells is treated and then distributed for public use. In addition, several

private residence (domestic) water wells are located in the vicinity of the site to the

west/northwest; the closest domestic well is within Yt-mile of the site. The domestic wells are all

completed in either the 200-foot or 500-foot sands.

Site Hydrogeology

The shallow surface soil and geology underlying the site consists of fill, alluvium, and

unconsolidated terrace deposits. Surficial fill covers the majority of the site, with a clay

(cohesive) unit underlying the fill, and a sand (granular) unit is present within the clay unit at the

northwest portion of the property. The fill varies in thickness from I to 12 feet and consists of

sand, clay and shells. The clay unit consists of silty clay, clayey silt, and sandy clay. In general,

it becomes more cohesive with increasing depth. Where the sand unit is present, it reaches a

maximum thickness of 30 feet (near the Calcasieu River northwest of the site), and the clay

ranges in thickness from 20 to 36 feet above the sand. The sand pinches out to the south and east

4

near the center ofthe west service yard. Where the clay unit is present alone (the majority ofthe

site), it extends to over 170 feet below ground surface. In general, within 100 feet of ground

surface, the cohesive and granular units are the two water bearing units underlying the site (EPA

2000a).

A total of 11 groundwater monitoring wells were installed on or near the site to monitor the

surficial alluvial aquifer. A 12th well was plugged and abandoned after it was drilled through a

sewer line. Ofthese 11 wells, six (MW-l through MW-4, MW-8 and MW-9) monitor the sand

(granular) unit; four (MW-5, MW-7, MW- 10 and MW-ll) monitor shallow portions of the clay

(cohesive) unit, and one (MW-6) monitors groundwater in the discontinuous sand layer in the

clay. Two of the wells which monitor the clay (MW-5 and MW-7) are nested with wells (MW-2

and MW-8, respectively) that monitor the sand unit. The depth to groundwater is relatively

shallow, ranging from approximately 2 to 6 feet below ground surface (EPA 2000a).

Groundwater Flow Direction

According to the 2000 ROD (EPA 2000a), and based on groundwater gauging data, the general

groundwater flow direction in the shallow water table aquifer is north/northwest toward the river

and appears to be controlled by ground topography (EPA 2000a).

The 1998 EE/CA notes that Calcasieu River does not receive upstream flow since the

construction of a saltwater barrier two miles upstream of the site in 1968. The saltwater barrier

consists of a dam and canal that prevent the movement of salt water from the meander further

upriver. The canal diverts the flow of the Calcasieu River from the meander by bypassing it and

cutting off the meander; however, the meander does receive tidal flux via the Calcasieu River

downstream of the dam and canal. Consequently, the elevation of the river is sea level, and is

controlled by tides. One of the impacts of the tidal influenc~ is that water within the meander of

the Calcasieu Rivervaries from salt to fresh water. Typically, fresh water is present in the

meander of the river during the months of October through May, and during the remaining

months the meander contains saltwater (B&V 1998).

5

The 2002 Ground Water Sampling Report (B&V 2003a), states that groundwater flow is either to

or away from the river, and these changes in direction are more dependent on tidal activity than

seasonal variations, although high precipitation also influences flow direction. Tidal influences

on the groundwater flow direction in the alluvial aquifer were also noted in the RI and EE/CA

reports (B&V 1998).

3.2 LAND AND RESOURCE USE

The Site is a former gas production facility (manufactured gas plant) located on the south bank of

the Calcasieu River in Lake Charles, Louisiana. It consists of east and west service yards

separated by North Ryan Street (Figure I). The west service yard is approximately 16 acres and

is used as a storage area and repair center associated with the Lake Charles Service Center

operations. The east service yard is three to four acres in size and was originally leased for

storage; however, it is no longer used. The Site is bounded to the north by River Road and the

Calcasieu River, to the south by commercial businesses, to the southwest by waste water holding

ponds and a waste water treatment plant, and to the west by a cypress wetland. A drainage ditch

and an abandoned railroad spur are also located along the southern boundary of the Site and

separate the Site from the water treatment plant. The western edge of the Site is also bounded by

a drainage ditch and an unpaved access road for the wastewater treatment plant property (EPA

2006).

The Site is situated in a sparsely populated riparian area surrounded by industrial-zoned land. A

site layout map is provided as Figure 2.

3.3 HISTORY OF CONTAMINATION

The Site property was originally owned by the Lake Charles Ice, Light and Water Works

Company that operated an electric plant on the northeast portion from 1894 to 1909. Gas

production began in 1916 by the Lake Charles Gas Company, which operated on the

southeastern portion of the property untill924. The plant was then operated by the Lake

6

Charles Electric Company in 1925, Louisiana Electric Company, Inc., in 1926, and Gulf States

Utilities Company from 1927 to 1932; therefore, gas was produced at the site between 1916 and

1932 in the southeastern portion of the existing property (west service yard). Gas was

manufactured using the Tenney carbureted water gas process until 1931, when the plant was

converted to the Kenns horizontal carbureted water gas process for one year of production. The

annual production of gas during the years of operation at the Lake Charles gas plant ranged from

approximately 50 to 85 million cubic feet. Manufactured gas production was phased out when

natural gas service became available to the City of Lake Charles in 1932 (EPA 2004b).

Historical fire insurance maps show that the gas plant consisted of a structure that housed the gas

manufacturing equipment and materials (retorts, coke house, compressor, scrubbers, and

purifiers), an aboveground gas holder of unknown dimensions and capacity, seven aboveground

gas storage tanks, and two aboveground oil storage tanks. The maps also show that an electric

generating plant, a 300,000-galion capacity reservoir, a smaller reservoir of unknown

dimensions, and two partially underground tanks for crude oil storage (7,500 barrel and 2,000

barrel capacities) were located north and northwest of the gas plant. The reservoirs were likely

used for the storage of water for electric-generating processes, and according to the historical

maps, six water production wells were also present on site. Between 1919 and 1925, two

aboveground gas tanks, one rectangular scrubber, and two oil tanks located 90 feet east of the gas

holder were added to the site. The purifiers, storage tanks, reservoirs, and crude oil storage tanks

were removed from the site by 1949. In 1932, the Site ceased operations as a manufactured gas

plant (EPA 2004b).

The coal tar by-products generated during gas plant activities were reportedly discharged into

marshlands west of the gas plant. At this time, a wetland area of approximately six acres was

used as a landfill for the disposal of electric equipment, poles, appliances, and other waste.

Electric transformers, capacitors, and drums containing used transformer oil were reported to

have been disposed of in this landfill. In 1980, the landfill had reached capacity, was filled in

and covered with shells and soil, and was leveled to grade.

7

A storm water drainage pipeline (storm sewer) previously extended south to north across the

Site, and was formerly used by the City of Lake Charles and Entergy for the discharge of surface

water run-off. The pipeline discharged to the Calcasieu River before it was plugged with

concrete at its entrance and a steel plate at its terminus near the river (EPA 2004b).

Discovery of Site conditions, including potential groundwater contamination, occurred on

20 July 1988, when utility workers digging a trench along the Site's northern fence line

discovered an oily material leaking out of the side of the trench closest to the Site. The LDEQ

was notified of this discovery, and sampled this material in cooperation with the 1988 property

owner, GSU. A more thorough investigation of the Site revealed a pit where a black substance

was found at the surface in the center of the western utility storage yard.

On 19 September 1988, LDEQ ordered GSU to determine the extent of soil, sediment,

groundwater and surface water contamination and to propose a plan for remediation at the Site.

Three investigations by GSU were carried out: Phase I, II, and III investigations are dated

December 1988, March 1989, and March 1990, respectively. In October 1990, EPA performed a

Screening Site Investigation (SSI), which began in October 1990 and was completed in

September 1992. Samples collected during SSI field activities from Calcasieu River sediments

revealed a release of contaminants including polycyclic aromatic hydrocarbons (PAHs), volatile

organic compounds (VOCs) and polychlorinated biphenyls (PCBs) from the North Ryan Street

site into the adjacent Calcasieu River (EPA 2000a and Agency for Toxic Substances and Disease

Registry [ATSDR] 2006).

The site was proposed for the NPL in February 1995. An Administrative Order on Consent

(AOC) signed by both Entergy and EPA became effective on July 7,1997 (EPA 1997), making

this an EPA enforcement-lead project.

Remedial Investigation (RI) work on groundwater, surface water, soil, and sediment was

conducted by GSU, under EPA's oversight. As part of the RI, a Baseline Risk Assessment

(BRA) was performed in order to identify potential threats to human health by evaluating cancer

and noncancer risks posed to various populations that could possibly be exposed to any of the

8

contaminated soil, sediment, surface water, and groundwater on and around the site. In October

1999, an FS for OU I, the groundwater OU, was based upon the findings of the RI and BRA

(EPA 2000a). Only groundwater was evaluated in the FS because most of the threats to human

health and the environment posed by soil (also the coal tar source material) and sediment were

evaluated during the development ofthe removal response action. The considerations ofthe

non-time critical removal action are documented in the EE/CA (B&V 1998), the Action

Memorandum (EPA 1999) and the Administrative Order on Consent to Conduct the Removal

Action (EPA 1999). Additional information on the RI, an addendum to the RI, the EE/CA and

the removal actions performed is provided below.

RI and BRA Reports

RI activities performed included the excavation of seven test pits, the drilling of 28 soil borings,

the installation of six monitoring wells, and the collection of 22 sediment samples, 18 surface

water samples, and 12 groundwater samples (ASTDR 2006). The EE/CA and risk assessments

identified the following key problem areas: 1) soil contamination in a former marshland area

where tar by-products from the gas generation process had been disposed (the exposed tar area);

2) an area of soil along a storm sewer pipe extending from the former marshland area north to the

river; 3) west drainage ditch sediment and, 4) an area of Calcasieu River sediment located at the

end of the storm.sewer discharge point. The contaminants of concern were PAHs; PCBs; and

benzene, toluene, ethylbenzene and xylenes (BTEXs).

In March 1999, the BRA and an Addendum to the RI and EE/CA were completed. The objective

ofthe Addendum was to further evaluate the connection between subsurface soil contamination

and the river. In January 1999 and January 2000, annual groundwater sampling reports were

completed. Domestic well water from 25 additional wells was sampled in April 1999, and three

sources of contaminants were identified: the former manufactured-gas plant which operated

from 1916-1932, two fuel oil pits used from 1900-1920, and the marsh area used by GSU as a

landfill from 1932-1980. None of the disposal areas were contained; the coal tars were pumped

into the marsh, the fuel oil was stored in earthen pits, and the landfill was covered with soil and

shells to create a base for the storage yard. No records of waste type, amount, location, or

9

capacity of the pits were available. Fuel oil pits were located in the northern area of the site, near

the Calcasieu River, PCBs were found in areas associated with landfill operations on the site, and

a storm water drain line transported coal tar from the site to the river until 1995, when it was

plugged (ASTOR 2006).

Ecological Risk Assessment (ERA) Report

A Screening Level ERA was performed in 1998 and a final ERA was performed in 1999 (B&V

1999b). The final ERA evaluated three assessment endpoints that included protection of the

aquatic habitat, the fish community, and upper trophic receptors. Based on the comparison of

estimated exposure concentrations and doses to appropriate toxicity benchmarks, ecological risks

in the Calcasieu River sediments and cypress wetland were identified. Both river water and

sediments contained chemicals that may have presented a risk to ecological communities through

food-chain transfer. Surface water contained levels of metals but only slightly exceeding the

water quality criteria and are attributable to other sources. Sediments contained metals and

PAHs that posed an ecological risk. However, the cypress wetland did not appear to be typically

hydrologically connected to contaminated areas of the Site and existing contamination has not

been attributed to Site operations. Therefore, the cypress wetland was eliminated as an area of

concern for the Site (B&V I999b). Concentrations in soil and sediment were compared to the

National Oceanic and Atmospheric Administration (NOAA) Effects Range-Median (ER-M)

values for PAHs, which later on became the action levels for the removal action.

Action Memorandum

A June 1999 Action Memorandum (EPA 1999a) and an October 1999 AOC (EPA 1999c) was

signed to perform a non-time critical removal at the following areas of concern: Calcasieu River

sediment, storm sewer, west drainage ditch, and the exposed tar area. As a note, the 2004 ROD

discusses all these activities as being part ofOU 2, the Soil OU.

The Action Memorandum noted that, based upon the streamlined risk evaluation, the river

sediment did not pose a potential risk to human health. However, the ERA indicated that the

10

river sediment did pose a potential risk to the benthic community due to PAHs and some metals.

The specific objectives of the removal action as specified in the Action Memorandum that

implemented the EE/CA addressed the following:

• On-site contaminated soil areas, known as the exposed tar and storm sewer areas

o Limit the exposure of workers and visitors to chemicals of concern in this area ator near the surface

o Reduce the amount of heavily contaminated source material to minimize thecontinued threat of chemical migration from this material into the shallowgroundwater and surrounding soils

• Calcasieu River sediment at the storm water discharge point

o Reduce the direct ecological impact of contaminated sediment by reducing PAHsto below action level values

o Minimize the potential direct exposure of recreational users and indirect exposurefrom fish and shellfish consumption

o Limit migration of chemicals of concern in the Calcasieu River sediment away

from the point of elevated contaminant levels

The plarmed Removal Actions included: dredging, dewatering and disposal of river sediment;

excavation of storm sewer piping, bedding soil, and west drainage ditch sediments including

thermal treatment and/or disposal; and in-situ thermal treatment of soil in the exposed tar area.

EPA has set the goals for the interim removal action for total carcinogenic PAHs at 10

milligrams per kilogram (mg/kg) (calculated using B(a)P equivalents), 50 mg/kg total PCBs and

2 mg/kg total benzene. The removal action goals are the maximum concentrations of a

contaminant which may remain in a specific medium (i.e., soil) after treatment and still be

protective ofhuman health and the environment. The action level goals for the Calcasieu River

sediment are based upon screening level median values within the range that would affect

benthic organisms and are based on NOAA Screening Quick Reference Table for Organics.

These values were included in Appendix E ofthe EE/CA and are presented below:

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CompoundAcenaphtheneAcenaphthyleneAnthraceneBenzo(a)pyreneBenzo(a)anthraceneChryseneDibenz(a,h)anthraceneFluorantheneFluorene2-MethylnaphthaleneNaphthalenePhenanthrenePyreneLow Molecular Weight PAHsHigh Molecular Weight PAHsTotalPAHs

Action Level (mg/kg)5006401,1001,6001,6002,8002605,1005406702,1001,5002,6003,1609,60044,792

A risk assessment on the residual contamination at the Site post-removal has not been performed.

Removal Actions

Removal actions were completed in four principal areas in 2003 and are described in the

paragraphs below.

• Calcasieu River Sediment

During the Calcasieu River sediment removal action, more than 25,000 square feet of theCalcasieu River sediment were dredged, 1,023 tons of dewatered sediment weregenerated and disposed of off-site, and approximately 770,000 gallons of waste waterwere treated and discharged to the river (EPA 2004b). After dredging activities, sampleresults of the sediment that remained in the Calcasieu River verified that residualcontaminants remained in concentrations above the removal action goals (NationalOceanic and Atmospheric Administration [NOAA] Effects Range-Median [ER-M] valuesfor PARs); therefore, several areas in the river were over-dredged. However, some areaswith sediment concentrations exceeding the removal action goals could not beadditionally dredged due to their proximity to a sunken World War II ship carryingBunker C, a heavy fuel oil, and/or the reach of the crane's boom (EPA 2004b). Becauseremoval action goals were not met, a cap consisting of a geotextile fabric and Petraflex®,a concrete mattress consisting of interlocking blocks interconnected with nylon cabling,were placed over the river sediment area to provide stability and improve the aestheticappeal of the shoreline. A sediment cover, installed as an extension to the geotextilefabric and concrete mattress, was placed in the Calcasieu River to isolate and cover anyresidual contamination in the storm sewer outfall area. The liner system covers an areaapproximately 30-feet long by 64-feet wide (B&V 2004 and EPA 2004b).

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I

• Storm Sewer

Approximately 64 linear feet of the storm sewer was excavated to remove and dispose of278 tons of soil and approximately 27 tons of concrete off-site, and to remove, treat, anddischarge 30,000 gallons ofwaste water to the Calcasieu River (EPA 2004b). Uponremoval of the storm sewer piping and soil, confirmation soil samples collected from theexcavation bottom and sides verified that concentrations of the chemicals of concern(PAHs, PCBs, and benzene) were all below the removal action cleanup goals of 10, 50,and 2 mg/kg, respectively (EPA 2004b). The storm sewer excavation area was backfilledwith stabilized sand and road stone.

• West Drainage Ditch

Surface sediments were removed to a depth of approximately 6 inches over a 4- to 6-footwidth for a distance of 150 feet. Approximately 61 tons of sediment was removed fromthe ditch and transported off-site for disposal. The ditch was restored by sloping the sidesof the ditch to facilitate drainage and by placing road stone along the excavated portions.Waste water removed from the ditch, along with waste water generated during sedimentdewatering, was treated and discharged to the Calcasieu River. Sediment samples werecollected from the drainage ditch to document the level of residual contamination in theditch, but not to determine the extent of excavation required. The sediment samplescollected from the base of the ditch excavation contained total PAH concentrationsbetween 3.84 and 45.7 mg/kg and total PAH concentrations between 2.14 and 22.5 mg/kg(EPA 2004b).

• Exposed Tar Area

Removal action activities for this highly-contaminated area consisted of installingthermal wells within the exposed tar area and heating the contaminated material tovaporize and draw-off the organic contaminants. In-situ treatment to a depth of 6 feetover an area of 22,400 square feet was plarmed. Unfortunately, the thermal processrequired that groundwater in the treatment area be drawn down below the treatment zone,and pilot-scale wells for the thermal treatment process were installed in the area in March2001; repeated attempts by Entergy contractors failed to control the groundwater.Subsequently, EPA issued a decision to abandon the thermal treatment alternative and toproceed with the alternate action of excavation and disposal as specified in the 1999Action Memorandum (EPA 2004b). Soil and source material over the 22,400 square footarea were excavated to depths of either 2.5 feet or 6 feet, depending on the results ofprevious investigations (i.e. borings, probes and test pits emplaced by B&V).Approximately 7,375 tons of material was excavated, separated according to level ofcontamination, and disposed of off-site (EPA 2004b). During the removal action, visiblecontamination was observed in the area of sample collection below the road base cover,and soil samples were collected at the limits and base of the excavation. A total of 25base soil samples and 30 perimeter wall soil samples were collected from the excavationareas. PAHs were detected in all of the base and perimeter wall soil samples collected,

13

and laboratory analytical results ranged from 0.10 to 29,600 mg/kg. Benzene wasdetected in wall and base samples at concentrations ranging from 0.00042 to 160 mg/kg,and PCB concentrations ranged from 0.062 to 2,900 mg/kg. It has not been discussed inthe report if there isa typographical redundance regarding concentrations of total PAHs.Ten wall samples additionally analyzed for benzene using the Synthetic PrecipitationLeaching Procedure extraction method had concentrations ranging from 0.00073 to 0.94milligrams per liter (mg/L). The analytical results collected from the residual low-levelthreat waste were used to complete the revised human health risk assessment for the Site.The purpose of collecting these samples was to document the residual levels of soilcontaminants remaining after reaching the prescribed depths of2.5 or 6 feet (EPA2004b). After all ofthe grids were excavated and backfilled, a temporary coverconsisting of a compacted aggregate base was placed over the excavated area and graded.This cap was allowed to settle and consolidate before placing the final engineered cap(B&V 2003c). The full extent of the residual contamination has not been delineated, as itwas beyond the scope of the interim removal action under the EE/CA. Neither has a riskevaluation been performed to determine ifthere are ecological risks associated with theresidual contamination.

The installation of the engineered cap was the fmal activity for the removal action andwas initiated on February 17,2003. This activity involved removing the temporary capto a depth of 2.5 feet below ground surface (bgs), to avoid digging out contaminatedmaterial. During this excavation, groundwater was encountered, and as a consequence, insome areas the excavation was limited to 1.6 feet bgs. The sub-grade was reshaped, andthe geogrid, geotextile, and geomembrane components of the engineered cap wereinstalled (EPA 2004b, B&V 2003c). The temporary cap material and additional granular,road base backfill were also used within the composite liner and as the final surfacecover. Approximately 550 tons of road base material were imported to the site andformed a shaped 18 inch layer over the cap material; because the top of the cap wasraised, additional backfill was placed around the area to reduce the overall grade changerelative to the surrounding area (B&V 2003c). The 2004 ROD notes that a cap wasconstructed over the excavated area to a total height of approximately 3 feet at center andwas domed to allow surface water run-off (EPA 2004b). As-built drawings were notprepared for the cap, and the elevation of the dome observed during site visit performedon August 3,2010 was not very pronounced. Therefore, the statement in the AddendumNo.2 to the Removal Action report (B&V 2003c) that the cap was built according tospecifications could not be visually confirmed in the field.

As removal actions were on-going, the ROD for the Groundwater OU, OU 1, was signed on

September 27, 2000 (EPA 2000a). The remedial action objectives (RAOs) for this selected

remedy are as follows:


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• Prevent exposure to site contaminated groundwater above acceptable risk levels forpotential receptors

• Restore the site groundwater to human health-based standards following remediation ofthe exposed tar area

• Assure that no migration of contaminants from the groundwater is occurring whereby theimpact causes the surface water to exceed regulatory and/or risk-based standards relatingto human health and the environment.

The selected remedy for OU I included the following:

• Monitored natural attenuation (MNA) of groundwater, including sampling groundwaterwells installed to depths within the alluvial aquifer in order to confirm a decrease incontamination over time

• Monitoring surface water and drinking water supply wells to assure that contaminants donot exceed any regulatory or health based risk levels at points-of-exposure

• Ies which require that Entergy Gulf States, Inc, (Entergy) file a notice of groundwateruse restrictions and place them in the property records for the Site in order to preventhuman exposure to contaminated groundwater

• Operation and maintenance activities (O&M) for as long as contaminants exceedstandards.

The 2000 ROD noted that "a subsequent remedial action, to be named OU2, is planned to

address any residual source (soil/sediment) contamination remaining after both the source

removal and ground water remedial actions are completed. The response action in this ROJ) will

be consistent with the final action selected/or this site" (EPA 2000a).

In January 2003, a Revised BRA was prepared for Entergy Gulf States, Inc., the current owners

of the GSU site. This re-assessment evaluated the risks posed to future onsite workers by soil

contamination in the west yard of the site. The re-assessment was required with the completion

of sediment removal activities in the west yard near the former exposed tar area. For the

purposes of the Revised BRA, the west yard was divided into north and south portions. All soil

data from the west yard used during the baseline risk assessment were used in the revised

assessment with the exception of data from excavated areas. No revised assessments were made

to the other areas of the site because no unacceptable health risks were identified in these areas,

15

or wastes had been removed until removal action goals were met in these areas. The Revised

BRA found no current risk of exposure on site. The exposed tar area has been excavated and the

excavation site has been covered with fill material and capped (ASTDR 2006).

In 2004, EPA issued a ROD addressing OU 2 (EPA 2004b). This ROD stated that the "site

removal action addressed contaminated soil, sediment, and source material constituting

principal threat wastes and residual low-level threat wastes; therefore, because previous

responses at the Site andfor OU 2 eliminated the need to conduct further remedial action, the

selected remedial action is No Further Action Necessary, for OU 2[. ..], the Soil Operable Unit.

This remedial action is compatible with the remedy selectedfor OU 1, the Ground Water Ou,

and will be the final remedial action for this Site. This remedial action will leave low-level threat

wastes onsite and will require operation and maintenance activities including but not limited to,

Site maintenance, monitoring and compliance with the restrictions ofthe IC, to ensure that no

unacceptable exposures to risks posed by the Site or OU 2 occur in thefuture". So even ifNo

Further Action was the remedial action recommended, this OU is still subject to monitoring and

maintenance and is thus discussed in this FYR report.

A UAO was issued for the implementation of the OU I remedy in July 2005 (EPA 2005b);

this UAO implemented the Ground Water Remedial Action Plan (RAP) (B&V 2003b) that

provides the monitoring plan to assess the eflectiveness of MNA, the selected remedy of the

2000 EPA ROA.

On September 24, 2005, Hurricane Rita, a Category 3 hurricane, made landfall with top winds of

120 mph on the coast of southwestern Louisiana and caused flooding and property damage to

businesses and residences throughout Lake Charles. On September 30, 2005, LDEQ

representatives and contractors visited the site and reported no visual impacts at the site. That

same day, EPA collected two surface water samples at Gulf States Utilities as a preliminary

assessment ofpotential impacts from the hurricane. No constituents of coal tar contamination

were detected in either of these samples, and EPA concluded that the remediation steps taken at

the Gulf States Utilities site were not affected by Hurricane Rita (ASTDR 2006).

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A UAO was issued in July 2005 for the implementation ofthe au I remedy identified in the

RAP (B&V 2003b) and to implement lCs for this operable unit (EPA 2005b).

The following items are ofnote relative to the media addressed in the RODs for this Site:

• au I is called the groundwater au (EPA 2000a); however, the 2005 ROD addressingthis au also requires sampling of surface water at the edge of the mat that was placedover the residual impacted sediment in the river bed, and thus has a surface watercomponent associated with it.

• The ROD for au 2 refers to residual Soil Contamination (EPA 2004b); however, riversediment has also been addressed by this ROD that notes that "some areas with sedimentconcentrations exceeding the removal action goals could not be additionally dredged"and these areas were capped; however, no requirements for maintenance of this cap orimplementation of IC were found for sediment; the property ownership for this area wasnot apparent in the documentation reviewed.

3.4 INITIAL RESPONSE

Discovery of Site conditions, including potential groundwater contamination, occurred on 20

July 1988, when utility workers digging a trench along the Site's northern fence line discovered

an oily material leaking out ofthe side of the trench closest to the Site. The Louisiana LDEQ

was notified of this discovery, and sampled the material in cooperation with the 1988 property

owner, GSU. A more thorough investigation of the Site revealed a pit where a black substance

was found at the surface in the center of the western utility storage yard.

3.5 BASIS FOR TAKING ACTION

Based on data collected during a BRA performed by GSU as part of the RI, it was determined

that hazardous substances could be released from the Site that could endanger public health,

welfare, or the environment.

OU 1 - Groundwater

The 2000 ROD notes that the BRA was comprehensive in that it quantitatively evaluated the

noncarcinogenic and carcinogenic risks posed to various populations exposed to soil, sediment

17

surface water and groundwater on and in the site area. Although the ROD was developed to

address groundwater only, the findings of the R1 indicate that there is a connection between the

groundwater and Calcasieu River surface water, therefore the surface water pathway was

evaluated as part of the human health risk assessment (EPA 2000a).

For groundwater, the results of the risk characterization concluded that a noncancer or

noncarcinogenic Hazard Index (HI) of 28.5 and an excess cancer risk of 2.lxl 04 are associated

with the exposure of on-site workers to groundwater through ingestion and dermal contact while

showering. Both of these risks exceed acceptable levels. The noncarcinogenic risk is due

primarily to the dermal contact pathway (HI of22.1), whereas the cancer risk is primarily

associated with the ingestion pathway (1.4x104). The major contributors to the overall

groundwater risk are arsenic, barium, benzene, beryllium, fluoranthene, manganese, naphthalene,

and toluene (EPA 2000a).

Therefore if the response action selected in this ROD had not been implemented, an imminent

and substantial endangerment to public health, welfare, or the environment would have occurred

(EPA 2000a).

OU 2-Soil

The basis for taking action as No Further Action for this OU is outlined in the 2004 ROD

(EPA 2004b) as presented below. The areas of concern identified in the final BRA have been

addressed through a non-time critical removal action as follows:

• Ca1casieu River Sediment: Sediments were dredged based on exceedances of the cleanupgoals. Those sediments that exceeded standards and could not be excavated were cappedwith a geotextile fabric/concrete mattress or a sediment cover. These actions removedand managed the residual low-level threat wastes by eliminating the direct ecologicalimpact, minimizing the potential direct exposure of recreational users, minimizingindirect exposure from fish and shellfish consumption, and eliminating the sediment as asource for surface water contamination.

• West Ditch: Sediments in the west ditch were excavated and capped with road stone andthe surface water was removed, treated, and discharged. These activities eliminated the

18

direct ecological impact and eliminated the west ditch as a source area of contaminationfor the Calcasieu River as well as the future onsite worker or trespasser.

• Exposed Tar Area: Waste in the exposed tar area was excavated to a depth of either 2.5or 6 ft. An engineered cap consisting of geogrid, geotextile, and geomembranecomponents was installed over the area containing residual low level threat waste. Theseactivities eliminate the risks from potential exposure pathways for the utility andconstruction worker through inhalation of and direct contact with contaminants.

• Institutional Control: The conveyance notice that was filed with the property deed (Stateof Louisiana 2004) also protects human receptors from current and future direct,inhalation or ingestion exposure through the following restrictions: on excavation, use ofsoil, use of groundwater in the first water bearing zone, and use of property for purposesother than industrial or commercial

4.0 REMEDIAL ACTIONS

This section discusses the selected remedy, remedy implementation, O&M activities, and O&M

costs.

4.1 SELECTED REMEDY

OU 1 - Groundwater

According to the ROD for OU I (EPA 2000a), based on preliminary information relating to

types of contaminants, environmental media of concern, and potential exposure pathways, RAOs

were developed to aid in the development and screening of alternatives. These RAOs were

developed to mitigate, restore and/or prevent existing and future potential threats to human

health and the environment. The RAOs for the selected remedy for the OU I are:


• Prevent exposure to site contaminated groundwater, above acceptable risk levels forpotential receptors.

• Restore the site groundwater to human health-based standards following remediation ofthe exposed tar area.

19

• Assure that no migration of contaminants from the groundwater is occurring whereby theimpact causes the surface water to exceed regulatory andlor risk-based standards relatingto human health and the environment.

The removal objective ofreducing the amount of heavily contaminated source material to

minimize the continued threat of chemical migration from this material into the shallow

groundwater is listed as a specific objective of the removal action for the exposed tar area which

is considered source material as well as a contributor to the existing pocket of dense non-aqueous

phase liquid (DNAPL) found in the vicinity ofmonitoring well MW-6. Integration ofthe source

control aspect of the removal action with the groundwater remedial action is critical to achieving

the remedial action objective of aquifer restoration. The ROD (EPA 2000a) also stated that

although DNAPL is present, which is considered source material, the RI revealed that it has low

mobility due to its confinement within an isolated, unconnected sand lens surrounded by clay.

The findings in the RI support that source removal (e.g. removal ofthe DNAPL) is not needed.

The contaminants ofconcem (COCs) for OU I are as follows (EPA 2000a):

• Acenaphthene• Anthracene• Barium• Benzene• Beryllium• Ethylbenzene• Fluoranthene• Fluorene• Naphthalene• Pyrene• Toluene• Total Xylenes.

The remedial goals specified for these COCs are based on either respective maximum

contaminant level (MCL) specified under the Federal Safe Drinking Water Act (SDWA) or if an

MCL was not available for certain compounds, preliminary remediation goals (PROs) were

calculated utilizing the appropriate EPA guidance and this information is available in the OU I

FS dated October 1999 (EPA 2000a). These goals are further discussed in the applicable or

relevant and appropriate requirements (ARARs) section of this FYR report.

20

Based upon consideration of the requirements of CERCLA, and the detailed analysis of the

alternatives using the nine criteria, EPA selected the MNA and IC as the remedy for OU 1, the

groundwater OU. In addition, a contingency plan was incorporated as part of this remedy to

assure its success in meeting the remedial action objectives. The elements of the selected

remedy include (EPA 2000a):

• MNA of groundwater, including sampling groundwater wells installed to depths withinthe alluvial aquifer in order to confirm that a decrease in contamination is occurring.

• Monitoring surface water and drinking water supply wells to assure that contaminants donot exceed any regulatory or health based risk levels.

• ICs, which require that GSU file a notice of groundwater use restrictions and place themin the property records for the Site in order to prevent human exposure to contaminatedgroundwater.

In 2003, B&V compiled the RAP for OU 1 (B&V 2003b). This plan outlines the same COCs as

the 2000 ROD (EPA 2000a) but adds arsenic to the list of analytes. The reason for adding

arsenic is not explained in this RAP; discussions during the site inspection performed on August

3,2010, regarding arsenic indicate that it is naturally present at high concentrations in the

environment at the site. As such, it is unclear why arsenic continues to be analyzed in surface

and groundwater samples at the site. The remedial action for OU 1 was finalized in the UAO,

discussed below.

The 2005 UAO (EPA 2005b) required that groundwater monitoringfor PAHs, VOCs, and metals

be performed quarterly for the next three years. In addition, the site-specific characterization

data from the quarterly events would be analyzed annually to demonstrate the efficacy of natural

attenuation, as evidenced by decreasing trends in contaminant levels, at which point the results of

the analysis would be used to determine whether the monitoring program should proceed as is or

whether analytical parameters, sampling locations or sampling frequency should be revised. If

decreasing trends were evident after the third year, monitoring would continue annually, for a

period not to exceed ten years. If decreasing trends were not evident at the end of the third year,

then quarterly monitoring would continue until the FYR is conducted, at which time an

21

assessment of the monitoring program would be conducted and appropriate action would be

taken. A contingency plan would be considered at that time, but in order to allow for flexibility

based on changing technology and regulatory trends, no specific contingency is stated in the

UAO. The contingency plan may include establishing Alternate Concentration Limits (ACLs)

for the groundwater, filling for a technical impracticability waiver or consideration of one of the

other alternatives in the ROD (EPA 2005b).

au 2 - Soil

The selected remedial action for the soil Operable Unit, OU 2, was discussed in the 2004 ROD

for the Site. Due to the removal actions taken for OU 1, which addressed contaminated soil,

sediment and source material constituting the principal threat wastes at the Site, the selected

remedial action at OU 2 became No Further Action Necessary. The 2004 ROD states that "[t]his

remedial action is compatible with the remedy selectedfor OU 1, the Ground Water Operable

Unit, and will be the final remedial action for this Site" (EPA 2004b). However, although the

ROD selects No Further Action for this OU, the ROD recognizes that because the removal action

left low-level threat wastes on site operation and maintenance activities will be required. These

activities include, but are not limited to: Site maintenance, monitoring, and compliance with the

restrictions of the IC, to ensure that no unacceptable exposures to risks posed by the Site or OU 2

occur in the future. The IC is a conveyance notice to be filed with the property deed describing

the land use restrictions necessary to control site worker and environmental exposure to residual

low-level threat contamination as well as to prevent off-site contaminant migration. These

restrictions would prohibit any unauthorized excavation or use of contaminated soil, and limit

future use of the property to commercial or industrial purposes.

4.2 REMEDY IMPLEMENTATION

au 1,... Groundwater

The groundwater remedy did not require any additional construction (post removal action).

Quarterly sampling and gauging of Site monitoring wells and annual sampling of City of Lake

22

Charles water supply was initiated in 2006 as per the RAP (B&V 2003b). In addition to the

groundwater sampling, annual sampling of surface water is performed at five locations in the

Calcasieu River (B&V 2003b). To date, Annual Reports were available for review for 2006,

2007,2008, and 2009, although sampling has continued in 2010 as planned. Data from these

sampling events are discussed in the operation and maintenance section of this report.

As far as ICs for this au, a Restrictive Covenant (file No. 2672106) was filed with the Clerk of

Court on 17 May 2004 (State of Louisiana 2004). This use restriction covenant was binding for

the portion of land, situated in the City of Lake Charles, Parish of Calcasieu, State of Louisiana,

in Section 31, Township 9 South, Range 8 West, bounded on the east by North Ryan Street, on

the north by the Calcasieu River, on the west by lands of the City of Lake Charles, and on the

south by lands of the City of Lake Charles, bearing Municipal No. 303 North Ryan Street (the

"Property"). For the Groundwater au, this covenant states under item I that: "No use shall be

made ofgroundwater from both the unconfined water bearing sand (granular) unit and the

unconfined water bearing clay (cohesive) unit underlying the Property, with the exception of

groundwater collected on a periodic basis for sampling and analysis pursuant to any

Administrative Order(s) issued by the United States Environmental Protection Agency ("EPA"). "

This covenant is to run with the land and shall be binding on Entergy and all persons claiming

under Entergy for a period of 30 years from the date this covenant is recorded, after which time

this covenant shall be automatically extended for successive periods of 10 years. This covenant

may be terminated at any point only if an instrument containing the consent of the EPA, or its

successor, has been recorded.

OU2-Soi1

Although No Further Action was the selected remedy for this au (EPA 2004b), Site

maintenance, monitoring, and ICs were required to be implemented. Formal planning for

inspections and a&M activities at au 2 has not been developed.

As far as ICs for this au, a Restrictive Covenant (file No. 2672106) was filed with the Clerk of

Court on 17 May 2004 (State of Louisiana 2004). This use restriction covenant was binding for

23

the portion of land, situated in the City of Lake Charles, Parish of Calcasieu, State of Louisiana,

in Section 31, Township 9 South, Range 8 West, bounded on the east by North Ryan Street, on

the north by the Calcasieu River, on the west by lands of the City of Lake Charles, and on the

south by lands of the City of Lake Charles, bearing Municipal No. 303 North Ryan Street (the

"Property"). For au 2, this covenant states under item 2 that: "No non-de minimis amount of

soil on the Property shall be excavated, and no residential use ofthe Property may be made,

without either the prior written consent ofEntergy or the prior written consent ofEPA." This

covenant is to run with the land and shall be binding on Entergy and all persons claiming under

Entergy for a period of 30 years from the date this covenant is recorded, after which time this

covenant shall be automatically extended for successive periods of 10 years. This covenant may

be terminated at any point only if an instrwnent containing the consent of the EPA, or its

successor, has been recorded.

It is to be noted that the sediment cap that covers residual contamination in excess ofrisk-based

clean up goals is outside ofthe Entergy property that is captured in the Restrictive Covenant.

4.3 OPERATION AND MAINTENANCE

OU 1- Groundwater

The ground and surface water monitoring activities to be completed during the remedial action

were specifically addressed in the 2003 work plan (B&V 2003b). A field sampling plan (FSP)

and quality assurance project plan (QAPP) were provided as appendices to the RAP to satisfy

NCP requirements. Because of the nature of the activities to be completed as part of the

remedial action at the site, a remedial design, operation and maintenance plan, and contingency

plan were not required to implement the action.

Groundwater and surface water monitoring was planned to assess the success of MNA and

determine if the site has an impact on the deeper groundwater supply and the river. As part of

this remedial action, initially, quarterly sampling and analysis of monitoring wells at the site was

to be completed to monitor contaminant levels. Annual monitoring of surface water from the

24

Calcasieu River water and public supply water wells located southwest of the site would ensure

that surface water and deep groundwater are not being affected by site contamination.

According to this plan, Entergy was supposed to place a deed restriction on the property to

prevent any future use of shallow groundwater (B&V 2003b). Details on the RAP requirements

are provided below. Sample locations are depicted on Figure 2 ofthis report.

Groundwater Monitoring

Groundwater monitoring was to be performed quarterly at the site for a minimum of three years

to evaluate changes in contaminant concentrations in the groundwater and to determine if

contaminants with concentrations above the remedial action goals are migrating off site. After

three years of quarterly sampling, if decreasing trends were noted, the sampling frequency would

be performed annually for a period not to exceed ten years. After the annual monitoring, the

wells would be sampled once every five years until year 30. Iftrends did not show decreases,

the quarterly sampling would continue until 5 years, at which point the MNA program would be

. assessed and appropriate action taken. Groundwater samples were collected from all 11 site

monitoring wells. The groundwater samples were be analyzed for PAHs by SW-846 Method

8310, VOCs by SW-846 Method 8021, and selected metals (arsenic, barium, and beryllium) by

SW-846 Method 6010 (B&V 2003b).

The groundwater samples were collected following the protocol outlined in the FSP/QAPP

(Appendix A ofB&V 2003b). Water levels were gauged in all monitoring wells prior to sample

collection. The plan provided that during the first year of quarterly sampling, groundwater

samples from the monitoring wells would be analyzed for additional parameters, including

nitrate, nitrite, sulfate, sulfide, total and dissolved iron and manganese, carbon dioxide, total

organic carbon, and methane to support evaluation of MNA. Methane and carbon dioxide are

indicative end products of contaminant microbial degradation, carbon dioxide decreases under

the reducing conditions of anaerobic degradation, and iron and manganese can be reduced to

soluble forms during anaerobic degradation. This reducing condition can also convert nitrate to

nitrite and sulfate to sulfide (B&V 2003b).

25

Site monitoring wells were sampled quarterly in 2006,2007,2008, and 2009. Analytical results

are discussed in Section 6.4 of this report.

Surface Water and Public Well Sampling

Water samples were obtained annually from the Calcasieu River and from the six operating

public water supply wells, city wells G-8, G-9, G-lD, G-II, G-12, and G-B, which are located at

the Greater Lake Charles Water Company water plant to the southwest of the site. These six

wells were sampled in 2006, 2007 (twice sampled), and 2008. Only five wells were sampled in

2009, as Well G-13 was undergoing maintenance at the time of sample collection. Analytical

results are discussed in Section 6.4 ofthis report.

Surface water samples were to be collected from five locations along the Calcasieu River,

adjacent to the site. The sampling was to be completed annually for three years to evaluate

changes in contaminant levels and determine if additional action may be required at the site.

Sampling will continue annually until year ten, after which, the sampling would be completed

once every five years until year 30. The sampling requirement may be discontinued when the

remedial action goals are met. The ground and surface water samples were be analyzed for the

.same parameters as the monitoring well samples. Samples were collected annually in 2006,

2007,2008, and 2009 and analytical results are discussed in Section 6.4 of this report.

Reporting

The 2003 plan (B&V 2003b) required that a monitoring report be prepared annually after

completion of the fourth quarterly groundwater monitoring event and annual well and surface

water monitoring event. In addition, after completion of the fifth year of groundwater

monitoring, a remedial action report was to be prepared to include the same discussions and

information as the annual monitoring reports. The remedial action report was to additionally

compare the results of the quarterly and annual monitoring and provide rationale for termination

or continuation of the MNA program. Findings outlined in these reports are discussed in Section

6.4 of this report.

26

A contingency was specified in case at the end of the five years of monitoring, the groundwater

analytical results indicated the MNA process was not effective. If at that time it appeared that

the remedial action objectives could not be reached in a reasonable, remaining time frame, then a

contingency plan could be considered; however, consistent with the ROD, the specific

contingency was not named in the plan such as to allow for flexibility to account for changing

technology and regulatory trends (B&V 2003b). Because the 2003 remedial action plan was not

implemented until 2006, following the 2005 UAO, only four annual reports were available for

review for the FYR report.

MaintenancelRepairs

No specific maintenance requirements were specified in the RAP (B&V 2003b). The surface

water sampling locations require no maintenance and the city supply wells are maintained by the

Department of Public Works.

Repairs are made to the Site groundwater wells as necessary. During the August 3, 2010, site

inspection, the Entergy representative noted that in July 2010, the casing of well MW-1 was

replaced with an aluminum casing to better withhold impacts from salt water. No other

maintenance activities were documented in Site reports for the timeframe of the FYR.

OU2-Soil

O&M is required as part of the Post-Removal Site Control (PRSC) plan (B&V 2004). The goals

of the PRSC are as follows (B&V 2004):

• Implement ICs; a restrictive covenant will be bound to the property deed for 30 years toprohibit use of soil or residential use of the property

• Maintain the geosynthetic caps placed over the removal area in the west yard and overthe area of dredged sediment along Calcasieu River to ensure performance according to

27

specifications; the gravel cap was to be maintained annually to ensure integrity and thusprevent exposure of site workers to residual contamination

• Submit PRSC reports to EPA.

Institutional Control

In 2004, Entergy has recorded a restrictive covenant on the property with the State of Louisiana,

Parish of Calcasieu; this covenant included restrictions on groundwater use and soil removal

(State of Louisiana 2004). No ICs are in place for non-disturbance of the sediment capped in

Calcasieu River.

General Site and Cap Maintenance

The PRSC Plan required no direct inspection of the geosynthetic cap over the former Exposed

Tar Area. According to this plan, only an annual visual inspection of the granular cover was

necessary to ensure that the cap maintained its integrity and no ponding is occurring. The annual

O&M activities would include a visual inspection ofthe river cap from the south shore of

Calcasieu River. The PRSC Plan specified that brief maintenance memoranda be prepared

annually to document the status of maintaining the deed restrictions, granular cover, and

geosynthetic cap (B&V 2004), but to date no formal inspections have been performed on the

caps at the Exposed Tar Area or along Calcasieu River where sediment was removed. However,

during the site inspection, Mr. Richard McCabe, the Entergy representative stated that he walks

these areas when he is present at the Site. He noted that additional road base was brought on Site

to be added to the cap at the Exposed Tar Area but no maintenance activities along the river were

noted. No restrictive covenants were available for review for either of the soils or the sediment

removal areas where residual contamination remained above action levels.

4.4 OPERATION AND MAINTENANCE COST

O&M costs for the Site include B&V support and expenses for Entergy employees: Richard

McCabe, John Fausett, and Jerry Roberts. Table 2 provides the approximate costs for the years

28

stated. Total costs were provided by Mr. Richard McCabe the Entergy Site representative on

August 12, 2010.

For comparison, the following cost information was available in decision documents:

• OU 1 - according to the 2000 ROD (EPA 2000a), the cost for the selected remedy, MNAand ICs had an estimated capital cost: $23,400 (including legal and support fees toimplement the deed restrictions, attend meetings, and perform other coordinationactivities and assuming that only the groundwater underneath the site property wouldrequire deed restrictions), and estimated annual O&M cost of $73,500.

• OU 2 - no costs were provided for the implementation of the selected remedy in the 2004ROD (EPA 2004b), which was No Further Action, with the requirement for continued,Site maintenance, Site monitoring, and an IC implementation.

5.0 PROGRESS SINCE THE PREVIOUS FYR

This is the first FYR for the GSU Superfund Site.

6.0 FYR PROCESS

This section presents the process and findings ofthe first FYR. Specifically, this section

presents the findings of surveys; a site inspection; an ARARs review; and a data review.

6.1 ADMINISTRATIVE COMPONENTS

The first FYR review team was lead by Mr. Valmichael Leos ofthe EPA (Remedial Project

Manager) with field participation from Mr. Philip Allen, EPA, and Mr. Michael Miller, LDEQ

Project Manager. Ms. Cristina Radu and Mr. Gary Desselle, representatives from EA, assisted in

the review process.

In June 2010, the review team established the review schedule, which included the following

components:

29

• Community Involvement• Document Review• Data Review• ARAR Review• Site Inspection• Site Interviews• FYR Report Development and Review.

These components are discussed in the following subsections.

6.2 COMMUNITY INVOLVEMENT

A notice was published in November 2009 that EPA has initiated the FYR for this Site. A copy

of this notice is included as Attachment 5 to this report. Upon signature, the first FYR report

will be placed in the information repositories for the Site; the LDEQ office in Baton Rouge,

Louisiana; and the EPA Region 6 office in Dallas, Texas. A notice will then be published in the

local newspaper to summarize the findings of the review and announce the availability of the

report at the information repositories.

6.3 DOCUMENT REVIEW

This first FYR for the Site included a review of relevant Site documents, including the RODs for

OU 1 and OU 2, the 1997 AOC, removal action reports, the 2003 RAP, annual groundwater

monitoring inspections reports, the Final Close Out report, and other ancillary documents. As a

result of this review, it was found that the GSU has not been placed on the NPL, as proposed on

13 February 1995 (EPA 2000a). The complete list of documents reviewed during this First FYR

is provided in Attachment 1.

6.4 DATA REVIEW

There are no data applicable to OU 2, so this section will describe the data collected to satisfy

RAOs for OU 1. Groundwater and surface water data are collected on a quarterly and annual

basis, as described in Section 4.3 ofthis report. The following groundwater monitoring reports

30

were available for review (note that although they are called "Ground Water Monitoring

Reports", they also include surface water and City of Lake Charles supply well sampling

information):

• "2006 Ground Water Monitoring Report, North Ryan StreetlLake Charles ManufacturedGas Plant Site" (B&V 2007)

• "2007 Ground Water Monitoring Report, North Ryan Street/Lake Charles ManufacturedGas Plant Site" (B&V 2008)



The following sections describe the findings of these reports.

2006 Annual Report (B&V 2007)

Quarterly Groundwater Gauging and Sampling Results

Monitoring wells were gauged quarterly during 2006, and samples were collected from the 11

monitoring wells in January, June, September, and December. Standards for Site COCs were

exceeded in samples from MW-06 (benzene, ethylbenzene, toluene, acenaphtene, anthracene,

benzo(a)pyrene [B(a)P], fluorene, and pyrene), MW-03 (benzene), MW-4 (benzene), MW-5

(B(a)P), MW-7 (barium), and MW-9 (benzene). In addition, exceedances of MCLs were noted

in samples collected from MW-6 for arsenic, carbon tetrachloride, and 1,2-dichloroethane; these

compounds are not COCs for the Site. Arsenic MCL was also exceeded in MW-11. Some

exceedances were only in one sample.

Annual Supply Well Sampling

One to four PAHs were detected in all supply wells with the exception of G-ll. The most

significant detection was that ofB(a)P at 0.882 micrograms per liter (flglL) in G-12, which is

above the MCL. Moreover, 1,2-DCA was detected at a concentration of 1.21 flg/L in well G-lO;

31

the MCL for 1,2-DCA is 5 Ilg/L. These hits, although for compounds also detected in Site wells

were discarded on the basis that this wells are located hydraulically upgradient from the Site and

their screened intervals are separated from the Site contamination by clay formations acting as

confining layers.

The rationale of sampling these wells in conjunction with the Superfund Site seems then to be in

contradiction with the reasons stated above for discarding the hits as relevant. It is either that (I)

water quality in these supply wells is monitored to ensure they are not impacted by the

Superfund Site because a potential hydraulic connection is assumed to exist between the two

aquifers, or (2) these wells are considered separated from the site, in which case they should not

be sampled in conjunction with the monitoring program for the Site. Because of the significant

pumping stresses in these supply wells, gradients are not well defined, so assuming these wells

are upgradient from the Site is not substantiated. The compounds detected in these wells are in

general not very mobile, so their presence (one above its MCL) should be further researched.

They are not naturally occurring, so they may be attributable to another source of contamination.

Annual Surface Water Sampling

There were no detections above the EPA National Recommended Water Quality Criteria (WQC)

(for water plus organism) with the exception of that for benzo(b)fluoranthene in the sample

collected at SW-4. The concentration was 0.184IlgIL, compared to the WQC ofO.0038IlgIL.

2007 Annual Report (B&V 2008)

Quarterly Groundwater Gauging and Sampling Re:mlts

Monitoring wells were gauged quarterly during 2007, and samples were collected from the II

monitoring wells in February, May, August, and November. Standards for Site COCs were

exceeded in samples from MW-06 (benzene, ethylbenzene, toluene, acenaphtene, anthracene,

B(a)P, fluorene, and pyrene), MW-03 (acenaphthene), MW-4 (benzene), MW-7 (barium), and

MW-9 (benzene and acenaphthene). Some exceedances were only in one sample. In addition,

arsenic was detected in MW-IO and MW-l1 above its MCL. Detection limits for B(a)P in

32

samples from MW-3, MW-4, MW-6, and MW-9 were at times higher than the MCL, so potential

exceedances in these wells for this compound may not have been detected.


In 2007, supply wells were sampled twice, in May and August. No cleanup goal exceedances

were noted in 2007.


There were no concentrations above the detection limit in surface water samples. However, the

detection limit for benzo(b)fluoranthene was significantly higher than the WQC, so for this

compound, it cannot be ascertained if it exceeds the standard of 0.0038 f.1g/L in 2007; the annual

report does not recognize this fact.

2008Annual Report (B&V 2009)



monitoring wells in February, May, August, and November. Site cac standards were exceeded

in samples from MW-06 (benzene, ethylbenzene, toluene, anthracene, B(a)P), MW-4 (benzene),

MW-7 (barium), and MW-9 (benzene). Arsenic MCL was exceeded in samples from MW-l1.

Since December 2006, the detection limit for B(a)P in MW-3 has been above the MCL of

0.2 f.1g1L, so no determination can be made regarding this compound in MW-3.


In 2008 there were no cleanup goal exceedances in supply wells.


There were no concentrations above the detection limit in surface water samples.

33

2009Annual Report fB&V 2010)



monitoring wells in February, May, August, and November. Standards for Site COCs were

exceeded in samples from MW-06 (benzene, ethylbenzene, toluene, anthracene, B(a)P, fluorene,

pyrene), MW-4 (benzene), MWc7 (barium), and MW-9 (benzene). Arsenic MeL was exceeded

in MW-I1.


In 2009, supply wells with the exception of 0-13 were sampled once. Well 0-13 was not

sampled in 2009 because it was undergoing maintenance at the time of sample collection. No

standards were exceeded in any of the wells.


There were no concentrations above the detection limit in surface water samples. No cleanup

goal exceedances were noted; detection limits for benzo(b)fluoranthene could not be verified as

the analytical data sheets for surface water samples were not included in the 2009 annual report.

General Observations on Site Data:

Although water levels were gauged quarterly in wells between 2006 and 2009, no potentiometric

surface maps were drawn and the direction of groundwater flow is not discussed in detail in the

reports. The 2006, 2007, and 2008 annual reports state that "The depth to ground water and the

general flow pattern are consistent with previous sampling events at the site, with ground water

flow to the northwest." Only in the 2009 report is the tidal influence at the Site recognized:

"During all 2009 sampling events, ground water elevations show ground water flow to the

southwest, away from the Calcasieu River. Water levels were collected in the early morning

when the river was at high tide. Historically, flow both away and toward the river has been

observed, depending on the time ofday ofwater level collection."

34

Given the variable groundwater flow direction at the site, discussions in the annual reports

regarding monitoring wells located "upgradient" and "downgradient" from each do not seem to

be substantiated. Moreover, monitoring wells are noted to be located downgradient from the

City of Lake Charles supply wells; however, these wells are screened in different aquifers and

the flow direction in the deep aquifer is not discussed in the annual reports.

Although only B(a)P was detected above its MCL in supply well G-ll in 2006, acetone, 1,2

DCA, benzo(a)anthracene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(g,h,i)perylene,

chrysene, and indeno(l,2,3-cd)pyrene, and phenanthrene were detected at low concentrations in

supply wells. Most of these compounds are not very mobile. Their presence in groundwater in

. the deep supply wells may indicate migration to greater depths. The presence of organic

compounds in supply wells and the presence ofNAPL in at least one location at the Site,

emphasize the need for vertical delineation of the groundwater impact.

Plume delineation was based on exceedances of standards for organics in monitoring wells and

all plumes are shown to enclose wells MW-3, MW-4, MW-6, and MW-9. However, the

exceedance in 2006 for B(a)P at 0.243 Jlg/L in MW-5 and in 2009 of 0.249 Jlg/L in MW-IO are

not discussed and not depicted on the plume map. The exceedance in MW-IO in February 2009

is the first one that indicates the plume may have extended further south. The exceedances for

barium and arsenic in different sampling events in samples from MW-7, MW-10, and MW-11

are not depicted on any of the plume maps. Because ofthe Site stratigraphy, variable

groundwater flow direction due to tidal influence, and well screen intervals, there appears to be

insufficient data points to adequately delineate the overall groundwater impact.

MNA parameters were discussed in each annual report. In 2006, 2007, and 2008, the MNA data

indicate that a widespread reducing environment is present in groundwater at the site. However,

this environment is independent of the distribution ofthe contaminant plume. Based on the total

organic carbon results, it appears that the reducing conditions are associated with naturally

occurring organic matter (peat) and not the contaminant plume. The high percentage of

background or naturally occurring carbon in the groundwater at the site is likely to be digested

35

preferentially to carbon contributed from the contaminants. With an abundance of naturally

occurring carbon available, degradation of the contaminant plume will likely be negligible.

Concentration trend analyses were performed using the statistical portions of the Monitoring and

Remediation Optimization System (MARaS) software developed at the Air Force Center for

Environmental Excellence (AFCEE). The trend analysis indicates that as of 2009, trends remain

inconsistent across the site. The wells comprised within the plume at the Site are MW-3, MW-4,

MW-6, and MW-9. Wells MW-6 and MW-9 show mostly stable to decreasing trends, whereas

wells MW-3 and MW-4 generally show stable, increasing, and decreasing trends for chemicals

for which trends can be established.

A review of factors to be considered in the evaluation of the success of MNA is presented below:

MNAfactor

I. Has NAPL been recovered to the extentpracticable? Was NAPL ever much of anissue?

2. Have the groundwater plume(s) been fullycharacterized in the horizontal and verticalsense?

3. Is plume stable or declining, indicatingreceptors are not threatened within a twoyear travel-time frame?

4. Is plume shrinking such that remedialaction goals are achieved in a reasonabletimeframe?

5. Should the plume unexpectedly migrate,are any receptors within a 2 year traveltime?

36

Site Conditions

1. No removal of contamination has beenperformed below the groundwater table.

2. Vertical not delineated in highconcentration areas and some data gaps inhorizontal definition. Inadequate data andpiezometer clusters to evaluate net gradientsin horizontal and vertical.

3. Plume appears stable based on evaluation oftrends in monitoring existing wells.Additional wells may be necessary to verifyno plume migration.

4. No plume shrinkage has been noted for thelast 4 years. Unknown if a calculation of atimeframe for remediation has beenperformed.

5. Unknown. Lack of potentiometric surfacemaps of net head data precludesdetermination of seepage velocity.

6. Have geochemical indicators ofMNA(alkalinity, hardness, pH, solubleiron and manganese, sulfate, nitrate,carbon dioxide, methane, sometimeshydrogen, and redox potential) beenmeasured both inside and outside thecontaminant plume?

7. Have rate constants or degradation ratesbeen calculated?

8. Is the estimated time to achieveremediation reasonable?

9. Are there sufficient sampling points,including upgradient, downgradient,centerline, and sentinel points included inthe monitoring plan?

10. Is sample collection at least quarterly inthe first two years and annually thereafter?

6. Yes, with the exception of alkalinity andhardness.

7. No information was found regarding thiscalculation. No half-lives for COC andanalysis of degradation rates have beenprovided.

8. Contractor states destruction ofcontaminants may not be occurring. Timeto achieve standards may not be acceptable.

9. No specific sampling locations (monitoringwells) were installed in addition to the wellsinstalled during the Remedial Investigation.

10. Sampling frequency is satisfactory.

From the factors considered above, it is concluded that additional data, including site

characterization data, are necessary to complete a full evaluation of MNA as a valid remedy for

the Site. Overall, the data available so far are insufficient to confmn that MNA is or is not a

valid remedy for OU I. Perhaps the most significant unknown is rate of contaminant mass

reduction, and attendant projected cleanup time. As a result, "timeliness" of the MNA remedy

may not be acceptable. Nonetheless, no receptors are imminently threatened and the remedy

appears protective based on available data.

The 2000 ROD does not list arsenic as a Site COC; however, arsenic detection in wells varies

from concentrations as high as 71 !!g/L in MW-II (February 2007) to below detection limits of

3 !!g/L or lower in most other wells; the MCL for arsenic is 10 !!g/L. This variation in

concentrations among wells appears to be indicative of arsenic not being elevated due to its

occurring naturally in soil. A determination should be made if this COC is or is not Site related

and if not, what its source is. The mechanism of remediating metals in groundwater at the Site is

not described.

37

Overall, cursory reviews of the detection limits indicate that the analytical methods employed

were adequate. However, as noted above, in some instances detection limits were higher than

the clean up goal. Some tables (such as those depicting analytical results for surface water and

supply well samples) only list analytical results as "ND," instead as "less than the detection

limit." This required a cursory review of the raw analytical data sheets, during which some of

data sheets were found to be missing.

6.5 APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTREVIEW

As part of this FYR, ARARs identified previously for this site were reviewed to determine if any

newly promulgated or modified requirements of federal and state environmental laws have

significantly changed the protectiveness of the remedies implemented at the GSU Site. ARARs

for this Site were originally identified for groundwater in the ROD for OU 1 (EPA 2000) and for

soil and sediment removal in the Action Memorandum for OU 2 (EPA 1999a), which included

the EE/CA as Appendix B (B&V 1998). The ROD for OU 2 (EPA 2004) did not list any ARARs

because the selected remedial alternative was no further action.

The ARARs identified for the Site include chemical-, action- and location-specific requirements.

A detailed list ofARARs, as specified in the ROD for OU 1, and the Action Memorandum for

OU 2 are presented in Attachment 7. Many of the ARARs identified are no longer applicable

since those ARARs applied to specific activities associated with the remedial action that are

complete or no longer occurring at the Site. Therefore, as a practical matter, they are no longer

applicable to site remediation. However, ifadditional construction activities are initiated in the

future, these ARARs may become applicable.

One ofthe requirements of an FYR is to determine if there have been any changes to the ARARs

recommended in the ROD, or if there are any new requirements that may pertain to the site.

Although arsenic was not listed among the COCs for this Site in the 2000 ROD, according to the

Groundwater Remedial Goals listed in Section H ofthe same ROD, arsenic concentrations are

being measured in surface and groundwater samples collected at the Site (EPA 2000a). In 2009,

38

II

I concentrations up to 43 Jlg/L were detected. As a consequence, the federal requirement (MCL)

for arsenic needs to be considered.

6.5.1 Chemical-Specific ARARs

Chemical-specific ARARs are usually health- or risk-based numerical values or methodologies

that, when applied to site-specific conditions, result in the establishment of numerical values.

These values establish the acceptable amount or concentration of a chemical that may remain in

or be discharged to the ambient environment. If more than one chemical-specific ARAR exists

for a contaminant of concern, the most stringent level will be identified as an ARAR for the RA

for the specific medium.

For those COCs for which standards were not specified, PRGs were developed. A BRA for the

North Ryan Street/Lake Charles Manufactured Gas Plant Site was performed in 1999 (B&V

I999a). However, one toxicity value and several methodologies employed in the BRA have

changed in recent years.

The primary change has been the oral toxicological factor (reference dose [RID]) for

naphthalene. Naphthalene is the only groundwater COC with an RID that has been updated

since 1999. The RID for naphthalene has decreased by a factor of two from 4E-2 mg/kg-day to

2E-2 mg/kg-day. Thus, a recalculation of the non-carcinogenic hazard index would show an

increase by a factor oftwo.

A number of methodologies have changed since the BRA was prepared. Namely, the

methodologies for dermal toxicity adaptation were changed by EPA guidance in 2004 (EPA

2004a), and none of the dermal toxicological values used in the BRA are correct under current

methodologies. The methodologies employed in the calculation of the inhalation pathway have

also changed (EPA 2009).

The primary driver in the BRA for groundwater was ingestion so the changes to the dermal and

inhalation pathways are less significant than that of the RID for naphthalene. However, the

39

Human Health Risk Assessment (HHRA) should be revisited to determine if the EPA dermal

guidance (EPA 2004) and the EPA inhalation (EPA 2009) guidance affect the results of the

HHRA.

The BRA did not evaluate volatilization from groundwater or soil to indoor air. Generally, the

indoor air inhalation pathway was not considered significant in 1999 and only became of concern

in recent years for sites involving volatile contaminants in groundwater, in particular in areas that

have or could have future residential development. The concern is that users of a building above

the groundwater will be exposed to vapors that can migrate through volatilization into the

building from soil or groundwater. Volatiles detected in soil and groundwater should be

evaluated to address this issue.

As mentioned above, arsenic was not identified as a COC for this Site in the 2000 ROD (EPA

2000a). However, the Remedial Action Plan (B&V 2003) added arsenic as a compound to be

measured in both surface and groundwater samples and annual monitoring reports show that

indeed, these samples are analyzed for arsenic. However, because concentrations of arsenic

exceeding the MCL have been detected a discussion of the standards for arsenic is included in

this section. The MCL for arsenic of 0.010 mgIL became effective on January 23, 2006. Table 3

presents a comparison of the standards established in the ROD to the current MCLs.

No ARARs were specified in the RODs for the surface water. However, the Surface Water

Quality Standards for the State of Louisiana are an established ARAR for the site, and they

establish effluent limitations for wastewater discharges and water quality standards. Surface

water samples collected from the site should be compared to the numerical criteria established

for the Calcasieu River based on the use of the water body. Currently, the surface water

analytical data are compared to EPA National Recommended Water Quality Criteria (for water

plus organism) (B&V 2010), which are listed in Table 4.

40

6.5.2 Location-Specific ARARs

Location-specific ARARs are restrictions placed on the concentration of hazardous substances or

the conduct of activities solely because they are in special locations. No changes to location

specific requirements were identified for the GSU Site.

6.5.3 Action-Specific ARARs

Action-specific ARARs are usually technology- or activity-based requirements or limitations on

actions taken with respect to hazardous wastes or requirements to conduct certain actions to

address particular site circumstances. These requirements are triggered by the particular

remedial activities that are selected to accomplish a remedy. No changes to action-specific

requirements were identified for the GSU Site, but these should be reviewed if new remedial

actions are implemented at the site.

6.6 SITE INSPECTION

A site inspection was conducted on 3 August 2010, to assess the condition ofthe GSU Site and

the measures employed to protect human health and the environment from the contaminants still

present at the Site. Attendees included: (I) Philip Allen of the EPA; (2) Michael Miller of the

LDEQ; (3) Richard McCabe of Entergy; (4) John Fausett of Entergy; (5) Barbara Butler with

B&V; and (6) Cristina Radu ofEA. The site inspection checklist is included in Attachment 2,

site survey forms are provided in Attachment 3, and a photographic log of the inspection is

included in Attachment 4. Following the site visit, Mr. Allen and Ms. Radu interviewed

Mr. Russell Buckels, the superintendent of the Lake Charles Department of Public Works, Water

Division.

No evidence of contamination was visible at the Site. The Site's general appearance was good,

and the Site appeared to be well maintained. The inspection team observed the locations of the

41

monitoring wells, the cap over the former tar pit, the area of sediment removal, and the perimeter

of the facility, including the fences, warning signs, and gates.

Monitoring wells were in good condition and were equipped with appropriate locking devices.

At the time of the visit, the wells were not locked as the caps were removed the day before to let

water levels equilibrate prior to the quarterly sampling event that was on-going during the visit.

The Site is currently used by Entergy, so within the boundary of the facility natural vegetation is

not present. Vegetation outside of the boundary of the Site does not show signs of stress.

The cap over the Exposed Tar Area was noted to be in good condition, to the extent that its area

could be identified. Two things were noted: (I) the capped area was used for storage of heavy

equipment, including a repair truck and (2) the height of the cap could not be visually confirmed

in the field. It is unclear if the cap was constructed to withstand the weight of heavy machinery

stored on it. Also, because additional fill was used to reduce the elevation difference between

the top of the cap and the surrounding area and because there are no markers to delineate the

extent ofthe cap, an inspection performed by a person not familiar with the lay-of-thecland may

not necessarily cover the cap area.

The roads within the facility are in good condition. The fence that surrounds the facility is

standard 9-foot tall chain link and is topped with three rows of barbed wire on the southern and

most of the western boundary and with Concertina coil barbed wire on the northern and eastern

boundaries. Signs on the fence identify this facility as an active Entergy facility; no note of a

Superfund Site located on the premises was found. No signs of any kind were noted on the

western boundary of the property. However, being operational, the site has better security than

most places and entry on the property is controlled.

Some evidence ofponding water was seen along the western boundary fence. Apparently, high

tidal waters enter the area on the Water Utility side of the fence and in the past, Entergy had

expressed concerns regarding this water as well as possibly water from backwashing activities

that may enter the Entergy property.

42

6.7 SITE INTERVIEWS

In accordance with the connnWlity involvement requirements of the FYR process, key

individuals to be surveyed were identified by the EPA. Contacted individuals included LDEQ

project manager, the Site owner's representative, the Entergy contractor, and the superintendent

of the Water Utility located next to the Site. Due to the industrial location of the Site,

historically there seems to be no general public interest regarding Site activities. Completed

survey forms for the following individuals are included in Attachment 3:

• Mr. Michael Miller, LDEQ project manager;• Ms. Barbara Butler, Entergy contractor on behalf of the Site owner; and• Mr. Russell Buckels, Water Utility superintendent.

The only issue brought up by Mr. Miller referred to the effectiveness of the groWldwater remedy.

Mr. Miller indicated that as per B&V conclusions in the Armual Reports, degradation of

hydrocarbons of interest will likely not be effected in the foreseeable future due to the presence

of a large amoWlt of natnrally-occurring organic materials, which are essentially outcompeting

the constituents of concern for terminal electron acceptors. This potentially has the effect of

prolonging the cleanup time. Mr. Miller has shared his concerns with EPA and believes that the

FYR is the opportWlity to review the data and discuss potential options. In addition, Wlder

optimization of the Site operations, Mr. Miller noted that from his review ofthe documents

sunnnarizing the past removal actions, he gets the impression that there may well be source

material left in place beneath the existing equipment lay-down yard, near the highly impacted

monitor well. If this is the case some consideration should be given to another removal action in

that area. If all, or most, of such source material can be removed, it is likely that the

concentrations of constituents in the well will drop, which has the potential to reduce the time

required for attenuation down to the established remedial goals.

The only suggestions brought up by Ms. Butler was to cease sampling the City of Lake Charles

supply wells based on the analytical results ofthe last four years.

43

Mr. Buckles notes that he had discussions with Entergy regarding ponding water along the west

fenceline on City property as wells as potential future issues with repairing leaking buried water

pipes at the Site due to Entergy's reluctance to dig any soils.

No other issues were brought up by the stakeholders.

7.0 TECHNICAL ASSESSMENT

The conclusions presented in this section support the determination that the selected remedy for

the Site is currently protective ofhuman health and the environment. EPA Guidance indicates

that to assess the protectiveness of a remedy, three questions (Questions A, B, and C) shall be

answered.

7.1 QUESTION A: IS THE REMEDY FUNCTIONING AS INTENDED BY THEDECISION DOCUMENTS?

• RA Performance

o OU I: Based on the review of documents and monitoring data, there is noconclusive indication that the MNA remedy will be effective in remediating Sitecontamination in a timely manner and it will be effective for all Site COCs (suchas metals). As per the ROD, one more year of data collection is necessary toevaluate if this remedy is or is not effective and subsequently, contingencymeasures should be considered.

o OU 2: Caps are in place over areas where removal has not addressed the fullextent of the impact above the clean up goals; caps appear to be operating asdesigned. Formal O&M activities should be implemented on both the soil andsediment caps. In addition, no ICs appear to have been required in relation tonon-disturbance of the sediment cap.

• Cost of System and O&M-O&M costs for fiscal years 2005 through 2009 and coststhrough July 2010 were inclusive of all activities performed at the Site, including laborcosts for Entergy staff as well as any maintenance performed at OU 2. The estimatedcosts for the remedial actions available in decision documents covered only OU 1. As aconsequence, no direct comparison could be performed between actual and estimatedcosts. Currently, as described in the O&M activities (Section 4.3), no formal O&M isperformed at OU 2 and no associated reporting is prepared; a determination if allocatedfunds are sufficient to maintain the effectiveness ofthe current remedy cannot be made.

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• Opportunities for Optimization-An evaluation of the MNA should be performed; thisevaluation will likely result in installation of wells in locations adequate for MNAmonitoring. The activities at OU 2 are already minimal and inspections and O&M shouldbe continued. An analysis of the analytical results for the supply wells that will includethe rationale for the presence of Site COCs and other compounds exceeding MCLsshould be prepared. The lack of the interconnectivity between the two aquifers should bedocumented; EPA will review this information and determine if a change in themonitoring plan is warranted.

• Early Indicators of Potential Issues- The contractor has stated that the MNA remedymay not be effective for OU I; however, currently there is no complete pathway for thismedium, and as long as the plume is stable, the remedy (in concert with ICs) isprotective.

• Implementation of ICs and Other Measures-The security fencing around the Site isintact. Waming signs regarding the presence ofa Superfund Site are not present, andalthough remedy components located within the fence of the facility are secure, elementssuch as the sediment cover are not. ICs still have to be implemented to cover all aspectsoffuture use and necessary restrictions for groundwater, soil, and sediment.

7.2 QUESTION B: ARE THE ASSUMPTIONS USED AT THE TIME OF REMEDYSELECTION STILL VALID?

• Changes in Exposure Pathways-No changes in the Site conditions that affect exposurepathways were identified as part of the five-year review. This is due to several factors:primarily, there are no current or planned changes in land use, and secondly, no newcontaminants, sources, or routes of exposure were identified as part of this FYR.

• Changes in Standards, Newly Promulgated Standards, and To-Be-Considered-Thisfive-year review did not identifY any new requirements that would pertain to the SiteCOCs; arsenic, not currently a Site COC but a compound for which samples areanalyzed, had a change in MCL from 50 Jlg/L to 10 Jlg/L during the review period.

• Changes in Toxicity and Other Contaminant Characteristics-For the OU I remedy,naphthalene was the only compound for which the reference dose has changed so thePRG will be different than the one specified in the ROD. Also, risk methodologies havechanged since the risk assessment was performed; a reevaluation of the risk, includingvolatilization of compounds from groundwater or soil to indoor air should be considered.The remedy at OU 2 relies on containment of contaminants rather than cleanup orremoval of contaminants. Therefore, changes in toxicity or other factors forcontaminants of concern do not.impact the protectiveness of the remedy.

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• Changes in Land Use--There have been no changes in land use that bear on theprotectiveness of the selected remedies.

• New Contaminants and/or Contaminant Sources- A justification for the eliminationofarsenic as a COC, present in samples collected from several but not all wells at theSite, should be provided. Given that it is likely present in groundwater due to naturaloccurrence in soil, a rationale for its presence in such a wide range of concentrationsshould be provided. If determined that it is not Site related, eliminate it from the suite ofanalyses performed routinely at the Site.

• Expected Progress Toward Meeting RA Objectives

o For OU 1, additional data are necessary to fully evaluate the effectiveness ofMNA as a remedy; the remediation mechanism for metals is not described(specifically for barium, which is a Site COC).

o For OU 2, the objective consisting in isolating the residual contamination hasbeen met. ICs should be put in place to prevent exposure to contaminants atconcentrations above health-based risk levels that have remained at the Site in thelong term and limit activities at or near the Site.

7.3 QUESTION C: HAS ANY OTHER INFORMATION COME TO LIGHT THATCOULD CALL INTO QUESTION THE PROTECTIVENESS OF THE REMEDY?

No other information has been identified that calls into question the current protectiveness ofthe

remedy.

7.4 TECHNICAL ASSESSMENT SUMMARY

According to documents and data reviewed, the site inspection, and interviews, data are

insufficient to discern if the groundwater remedy is functioning asintended by the 2000 ROD

(EPA 2000a). Nonetheless, although not fully delineated, whereas the plume does not appear to

be unstable, cleanup times may be unacceptable. This conclusion of the FYR is consistent with

conclusions of the 2006, 2007, and 2008 Annual Reports(B&V 2007,2008, and 2009), that state

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the following: "It does not appear that natural attenuation of [manufactured gas plant] MGP

contaminants is occurring in the ground water" The 2009 Annual Report (B&V 20l 0) notes,

consistently with the previous annual reports, that "much ofthe MNA data indicate a widespread

reducing environment across the site; however, these conditions are not unique to the

contaminated areas, which would be expected in a typical naturally attenuating environment"

although it falls short of noting that MNA does not appear to be occurring in groundwater at the

Site. The 2000 ROD (EPA 2000a) provided for a contingency that data for five years since the

initiation of remedy be evaluated to determine if MNA is effective or not before the remedy is

reevaluated and appropriate action is to be taken. At this time, data for only four years were

available for review, but there is a strong indication that a contingency will be considered in the

future.

Currently, the soil and sediment remedies appear to function as designed. However, no ICs

restricting the future use and requiring maintenance of the remedies are in place at this time.

There have been no changes in the physical conditions of the Site that would affect the

protectiveness of the remedy. The ARARs cited in the RODs have been met. There have been

no changes in toxicity factors for the primary contaminants of concern and there has been no

change to the standardized risk assessment methodology that could affect the protectiveness of

the remedies. There is no other information that calls into question the protectiveness of the

remedy.

8.0 INSTITUTIONAL CONTROLS

ICs are generally defined as non-engineered instruments such as administrative and legal tools

that do not involve construction or physically changing the Site and that help minimize the

potential for human exposure to contamination and/or protect the integrity of a remedy by

limiting land and/or resource use (EPA 2005a). ICs can be used for many reasons including

restriction of Site use, modifying behavior, and providing information to individuals (EPA

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2000b). ICs may include easements, covenants, restrictions or other conditions on deeds, and/or

groundwater and/or land use restriction documents (EPA 200!). The following sections describe

the ICs required at the Site, the potential effect of future land use plans on ICs, and any plans for

changes to Site contamination status.

8.1 TYPES OF ICS IN PLACE AT THE SITE

ICs that will help ensure protectiveness in the long term include (I) restricting use of

groundwater; (2) prohibition on disturbance of the soil and sediment caps placed over removal

areas where post-removal residual contamination exceeds the removal action goals; and (3)

limitations on use of the property for industrial and commercia! purposes. Entergy filed a

Restrictive Covenant (file No. 2672106) with the Clerk of Court on !7 May 2004 to prohibit the

use of the shallow groundwater, the unauthorized excavation and use of contaminated soils at the

Site, and limit the future use of the property to commercial or industrial purposes (State of

Louisiana 2004). However, no protection is currently in place for the river sediment and the cap

covering the residual contamination in Calcasieu River. The area of sediment removal is not

Entergy's property; as a consequence, the options for instituting ICs covering the river sediments

should be evaluated.

8.2 EFFECT OF FUTURE LAND USE PLANS ON INSTITUTIONAL CONTROLS

No future land uses have been established or are anticipated for the Site that would require an

adjustment to the ICs currently being required to be implemented.

8.3 PLANS FOR CHANGES TO SITE CONTAMINATION STATUS

No changes to the status of the contamination at the Site are anticipated.

9.0 ISSUES

This section describes issues associated with the Site that were identified during the First Five-

48

year reVIew:

1. Overall, insufficient data are available to confirm that MNA is an effective remedy forOU 1, the groundwater OU. Data collection needs are outlined in the set of factors listedin Section 6.4.

2. Lack of formal inspections, O&M activities, and reporting for the cap at Exposed TarArea.

3. Lack offormal inspections, O&M activities, and reporting for the cap on the sedimentalong the river.

4. Evaluate the need for an IC for the sediment cap; determine the owner ofthe property onwhich the sediment cap is located and evaluate the adequate path forward for the remedycontrol.

5. Presence ofheavy equipment stored on the Exposed Tar Area cap that may not have beendesigned to withstand such stress.



8. Evaluate if arsenic should be a Site COC or is naturally occurring.


10. Interconnectivity between the shallow and deep aquifer (particularly the 200-foot zone),concern for which required sampling of supply wells, is not fully understood. Alternatesources may be present besides the GSU Site to account for early detections ofcontaminants (some of which are GSU COCs) in supply wells.

11. Annual depiction of groundwater flow direction and tidal influence is not available; thedegree to which groundwater discharges to surface water is not understood despite thefinding that sediment samples from Calcasieu River were found impacted during the RI.

12. Numerical ARARs for surface water have not been outlined in decision documents andthe 2009 annual report only considered Federal standards.

13. Reference dose for naphthalene has changed since the PRG for naphthalene wasdeveloped for groundwater.

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15. Analytical methods may not be adequate to achieve detection limits for comparison tocleanup standards such as B(a)P; receive analytical results for sample prior to dilution soconcentrations for all compounds in a sample can be evaluated against clean up goals.


Entergy is primarily responsible for implementing these actions. Upon approval of this five

year review, an administrative copy of this document will be sent to Entergy and a

conference call will be initiated by the EPA to discuss the findings of the report.

10.0 RECOMMENDATIONS AND FOLLOW-UP ACTIONS

This section describes the recommendations and follow-up actions associated with the Site that

were identified during the First FYR. Table 5 summarizes the recommendations and follow-up

actions for the Site.

11.0 PROTECTIVENESS STATEMENT

The remedy for the GSU Superfund Site cannot be found to be protective of human health

and the environment in the long term at this time. The remedy for the GSU Superfund Site

remains protective in the short term because, under the current land use, there is no evidence

of known current exposure to either groundwater or soil contamination. In order to ensure

both short- and long-term protectiveness, the performance ofthe action items as described

above and in this Five-Year Review Report must be appropriately addressed.

12.0 NEXT REVIEW

The Site requires ongoing FYRs. The next review will be conducted within the next five years,

but no later than September 2015.

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II

Figures

Tables

Attachment 1

Documents Reviewed

Attachment 2

Site Inspection Checklist

Attachment 3

Site Survey Forms

I

Attachment 4

Site Inspection Photographs

Attachment 5

Public Notice for Initiation of Five-Year Review

Attachment 6

Institutional Controls - Covenant for Restrictions on Use

J

Attachment 7

Original ARARs