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Five Year Review Report

Second Five Year Review Reportfor the

Triangle Chemical Company SiteBridge City, Orange County, Texas

September 2000

U.S. Environmental Protection Agency1445 Ross Avenue

Dallas, Texas 75202-2722

146333

FIVE-YEAR REVIEW

Triangle Chemical Company SiteEPA ID# TXD055143705

Bridge City, Texas

This memorandum documents EPA's approval of the Triangle Chemical CompanySecond Five-Year Review Report prepared by CH2M Hill, Inc., on behalf of EPA.

Summary of Five Year Review Findings

The Triangle Chemical Company site continues to be protective of human health and theenvironment. Data review lends credence to the presumption, made by the TNRCC andits subcontractor, that the groundwater contamination at the site is not migrating. Minordeficiencies were noted at the site (e.g., unlocked monitoring wells, damaged fencing),but none were significant enough to warrant a finding that the remedy is not protective.

Actions Needed

None of the deficiencies noted were significant enough to warrant questioning the futureprotectiveness of the remedy. The damaged fencing around the site should be repaired, acap should be placed on the inner casing of MW-3, locks should be placed on MW-3 andMW-8, MW-1, MW-3, and MW-9 should be sampled at least annually, and the siteshould be mowed on a regular basis.

Determinations

I have determined that the remedy for the Triangle Chemical Co. EPA Superfund site isprotective of human health and the environment, and will remain so provided the actionitems identified in the Five Year Review Report are addressed as described above.

DirectorSuperfund DivisionU.S. Environmental Protection AgencyRegion 6

TC_5YR_000928.WPO SEPTEMBER 2000

TRIANGLE CHEMICAL COMPANY SITESECOND FIVE YEAR REVIEW REPORT

[This page intentionally left blank.]

5YR 000928.WO SEPTEMBER 2000

CONCURRENCES

FIVE-YEAR REVIEW

for the

Triangle Chemical Co.EPA ID# TXD055143705

Ruben MoyaRemedial Project Manager

B. Wfj^/Gustavo T. Chavarria, Chief

^AR/OKTTX Project Management Section

Bv: j^^n^M^_William K. Honker, ChiefAR/OK/TX Branch

- ^ y / / y/By: /^••L^-<-< z'x^"'-fc2->- c''<- -<.Paul WendelSite Attorney

MariTpeycke,'Chie^ -Superfund Branch, Office of Regional Counsel

Pam Phillips /Superfund Deputy Division Director

Date: ^ / S ' / 6 ^————r——7-——————

Date: ^^/g^————/ • r /——f——

Date: ^//7/Q f————•^.———^y

Date: ^// 7 / ^ /

Date: n/0(

Date: ^l Ol

TC_5YR_000928.WPD SEPTEMBER 2000

Five Year Review Report

Second Five Year Review Reportfor

Triangle Chemical CompanyBridge City

Orange County, Texas

September 2000

PREPARED BY:

Region 6United States Environmental Protection Agency

Dallas, Texas

Work Assignment Number:EPA Region:Date Prepared:Contract Number:Prepared By:Telephone:EPA Work Assignment Manager:Telephone:

048-FRFE-06ZZ6September 200068-W6-0036CH2M HILL972-980-2170Tom Reilly214-665-8307

TC_5YR_000928.WO SEPTEMBER 2000



SEPTEMBER 2000


Executive Summary

The second five year review of the Triangle Chemical Company site located in Bridge City,Orange County, Texas was completed in August 2000. The results of this second five-yearreview, which covers the period since the first five year review dated July 1994, indicate that theremedy is continues to be protective of human health and the environment. Overall, the remedialactions performed appear to be functioning as designed. No deficiencies were noted that do notdirectly impact the protectiveness of the remedy. However, repairs to the fence and to themonitoring wells are suggested to maintain site security and long-term protectiveness.

The remedy was chosen to remove the principle threats to human health based on direct exposureto hazardous materials stored at the site, to prevent further degradation of surface andgroundwater quality, and to mitigate future impacts to human health, the environment, and sitedevelopment. To meet these objectives, the remedy for the site included the offsite incinerationand deep well injection of the contents of drums and tanks, the decontamination of onsitebuildings, the offsite disposal of contaminated debris and trash, mechanical aeration ofcontaminated soils, and groundwater monitoring. The ROD recommended that operations andmaintenance (O&M) include landscaping, fence repair, and 5 years of groundwater monitoring.Groundwater monitoring was to end after five years if no significant contamination was detected,or corrective measures would be evaluated if significant contamination was detected. Asupplemental groundwater investigation conducted in late 1988 and early 1989 concluded thathigher levels of contamination than previously thought existed in the shallow groundwater at thesite, but that monitored natural attenuation would be an effective remedy. O&M at the site nowincludes semi-annual groundwater monitoring and site inspections of the fencing, warning signs,and monitoring wells, and mowing as necessary.

The remedial action at the site as originally set forth in the Record of Decision has beenimplemented as planned and continues to be protective of human health and the environment.

TC_5YR_000928,WPO PAGEES-I SEPTEMBER 2000



TC_5YR_0009?8.WPD SEPTEMBER 2000

Table of Contents

Section Page

Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ES-1List of Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iiiFive Year Review Summary Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v

I.0 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22.0 Site Chronology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43.0 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44.0 Remedial Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

4.1 Remedy Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84.2 Remedy Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84.3 Operations and Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94.4 Progress Since First Five Year Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

5.0 Five Year Review Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116.0 Five Year Review Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

6.1 Interviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126.2 Site Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126.3 Review of O&M Costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146.4 Standards Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146.5 Data Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

7.0 Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168.0 Deficiencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179.0 Recommendations and Follow-up Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1710.0 Protectiveness Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17II.0 Next Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

FiguresFigure 1: Site Map

TablesTable 1: Chronology of Site EventsTable 2: Annual O&M Costs Since Last Five Year ReviewTable 3: Actions Taken Since Last Five Year ReviewTable 4: Selected Groundwater Detections Since Last Five Year ReviewTable 5: Currently-Identified DeficienciesTable 6: Recommendations and Follow-Up Actions

TC_5YR_000928.WPD PAGEI SEPTEMBER 2000

Table of Contents

AttachmentsAttachment 1: List of Documents ReviewedAttachment 2: Interview Record FormsAttachment 3: Site Inspection Checklist/Inspection Roster/O&M CostsAttachment 4: Site Inspection Photographs

TC_5YR_000928.WPD PAGEII SEPTEMBER 2000


List of Acronyms

ARARs Applicable or Relevant and Appropriate RequirementsCERCLA Comprehensive Environmental Response, Compensation, and Liability ActCD Consent DecreeCFR Code of Federal RegulationsCOC Chemicals/Contaminants of ConcernEPA United States Environmental Protection AgencyFR Federal RegisterHI Hazard IndexLDR Land Disposal RestrictionsNCP National Oil and Hazardous Substances Pollution Contingency PlanNPL National Priorities ListMCLs Maximum Contaminant LimitsO&M Operation and MaintenanceOSWER Office of Solid Waste and Emergency ResponseOUs Operable Unitsppb parts per billionPCE TetrachloroetheneRA Remedial ActionRCRA Resource Conservation and Recovery ActRD/RA Remedial Design/Remedial ActionRI/FS Remedial Investigation/Feasibility StudyROD Record of DecisionSARA Superfund Amendments and Reauthorization ActSH State HighwayTAT Technical Assistance TeamTBC To Be ConsideredTDWR Texas Department of Water ResourcesTNRCC Texas Natural Resources Conservation CommissionTWC Texas Water CommissionVOCs Volatile Organic Compounds

TC_5YR_000928.WPD PAGE ill SEPTEMBER 2000



TC_5YR_000928.WPD PAGE IV SEPTEMBER 2000

TRIANGLE CHEMICAL COMPANY SITESECOND FIVE YEAR REVIEW REPOflT

Five Year Revie

SITE IDEN

Site name (from WasteLAN): Triangle Chemical

EPA ID (from WasteLAN): TXD055143705

Region: EPA Region 6

w Summary F

TIFiCATION

Company

State: TX

^orm

City/County: Bridge City/Orange

SITE STATUS

NPL Status: a Final s Deleted n Other (specify):

Remediation status (choose all that apply): o Under Construction n Operating jaComplete

Multiple OUs? n Yes s No Construction completion date: March 12,1987

Has site been put into reuse? nYes a No Site is abandoned.

REVIEW STATUS

Reviewing agency: a EPA a State oTribe a Other Federal Agency:

Author: EPA Region 6, with support from RAC6 contractor CH2M HILL

Review period: July 1994 through August 2000

Date(s) of site inspection: August 9,2000

Type of review: n. Statutoryeg Policy

D Post-SARA s Pre-SARA n NPL-Removal onlyD Non-NPL Remedial Action Site o NPL State/Tribe-leado Regional Discretion

Review number: n 1 (first) s 2 (second) n 3 (third) o Other (specify):

Triggering action:D Actual RA Onsite Construction g Actual RA Starto Construction Completion s Recommendation of Previous Five Year Review ReportD Other (specify):

Triggering action date (from WasteLAN): July 1994

Due date (five years after triggering action date): July 1999

TC 5YR_000928.WPD PAGEV SEPTEMBER 2000


Five Year Review Summary Form

Deficiencies: »

The following deficiencies were noted during the site inspection and/or data evaluationconducted for this five year review:• The fence is damaged and/or missing in three observed locations: (1) an approximate 20

foot length of fence is missing along the perimeter adjacent to monitor well MW-8, and theadjacent remaining sections are damaged (southwest property line), (2) the fence isdamaged at the southern comer of the perimeter and (3) the fence is damaged and almostcompletely down near the eastern comer of the perimeter.

• The grass at the site has not been mowed in at least a year, and is very overgrown.• Monitor wells MW-3 and MW-8 do not have locks.• Monitor well MW-3 does not have a cap on its PVC casing.• Monitor wells MW-1, MW-3, and MW-9 were dropped from the semi-annual O&M

groundwater sampling program during the 1999 events due to lack of detections.

These deficiencies do not currently affect the protectiveness of the remedy.

Recommendations and Follow-up Actions:

• Repair the fence to prevent unauthorized access, possible tampering with wells, andvandalism.

• Provide a new PVC cap for the inner casing of MW-3, and add locks to outer casings ofMW-3 and MW-8.

• Keep site mowed on a regular basis per the original requirements of the ROD.• Add monitor wells MW-1, MW-3, and MW-9 back into the O&M monitoring program at

least annually to verify the continued lack of contaminant migration.

Protectiveness Statement(s):

The remedy completed for the Triangle Chemical site continues to be protective of humanhealth and the environment.

Other Comments: None.

TC_5YRJ)00928.WPD PAGE VI SEPTEMBER 2000

Second Five Year Review ReportTriangle Chemical Company Site

The United States Environmental Protection Agency (EPA) Region 6 has conducted a second

five year review of the remedial actions implemented at the Triangle Chemical Company site

located near Bridge City in Orange County, Texas, for the period July 1994 through July 2000.

The purpose of a five year review is to determine whether the remedy at a site remains protective

of human health and the environment. This report documents the results of the review for this

site, conducted in accordance with EPA guidance on five year reviews. EPA RAC6 contractor

CH2M HILL provided support for preparation of this five year review report.

Existing EPA guidance on five year reviews includes the following:

• Office of Solid Waste and Emergency Response (OSWER) Directive 9355.7-02 (May 23,

1991), Structure and Components of Five-Year Reviews (introduced five year review

requirements).

• OSWER Directive 9355.7-02FS 1 (August 1991), Factsheet: Structure and Components of

Five-Year Reviews.

• OSWER Directive 9355.7-02A (July 26, 1994), Supplemental Five-Year Review Guidance

(introduced level of review considerations for sites where response is ongoing).

• OSWER Directive 9355.7-03A (December 21, 1995), Second Supplemental Five-Year

Review Guidance (identified three purposes of five year review and emphasized that reviews

must include a signed protectiveness determination, along with recommendations to correct

deficiencies.

Guidance provided in these documents has been incorporated into the five year review performed

for this site, as have the concepts outlined in the Draft Comprehensive Five-Year Review

Guidance, October 1999, OSWER Directive 9355.7-03B-P.

TC_5YR_000928.WPD PAGE 1 OF 18 SEPTEMBER 2000


1.0 IntroductionThe five year review for the Triangle Chemical Company site is required as a matter of EPA

policy rather than by statute.

Statutory reviews are required for sites where, after remedial actions are complete, hazardous

substances, pollutants, or contaminants will remain onsite at levels that will not allow for

unrestricted use or unrestricted exposure. This requirement is set forth by the Comprehensive

Environmental Response, Compensation, and Liability Act (CERCLA) and the National Oil and

Hazardous Substances Pollution Contingency Plan (NCP). Statutory reviews are required only if

the ROD was signed on or after the effective date of the Superfund Amendments and

Reauthorization Act of 1986 (SARA). CERCLA §121 (c), as amended by SARA, states:

"If the 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 five years after the initiation of such remedial action to

assure that human health and the environment are being protected by the remedial action

being implemented."

The NCP §300.430(f)(4)(ii) of the Code of Federal Regulations (CFR) states:

"If a remedial action is selected that results in hazardous substances, pollutants, or

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

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

five years after the initiation of the selected remedial action."



Because the ROD for the Triangle Chemical Company site was signed before October 17, 1986,

a five year review is not required for this site under the statute cited above. However, EPA

conducts five year reviews as a matter of policy if any of the following apply:

• Sites where a remedial action selected on or after October 17, 1986 (post-SARA), will

allow for unlimited use and unrestricted exposure upon completion, but where it will take

longer than five years to complete.

• Sites where a remedial action selected prior to October 17, 1986 (pre-SARA) leaves

hazardous substances, pollutants, or contaminants are left onsite above levels that allow

for unlimited use and unrestricted exposure. [Note: this is the requirement that applies to

the Triangle Chemical Company site.]

• Sites on the National Priorities List (NPL) with only a removal action, where hazardous

substances, pollutants, or contaminants are left onsite above levels that allow for

unlimited use and unrestricted exposure, where construction is complete, and where no

further action will take place.

• State or Indian Tribe-lead NPL sites, where the remedy isn't selected under CERCLA

§ 121 and where hazardous substances, pollutants, or contaminants are left onsite above

levels that allow for unlimited use and unrestricted exposure.

• Regions may also choose to conduct a policy review at a site with a no-action Record of

Decision (ROD), where monitoring is taking place to ensure the absence of contaminants,

or where factors contributing to the assumptions underlying the no-action decision may

have changed.

The first policy review for a site is due five years after the site has achieved construction

completion.

This is the second five year review for the Triangle Chemical Company site. The triggering

action for this policy review is the date of completion of the first five year review, in July 1994.



This review is required because hazardous substances, pollutants, or contaminants were left

onsite above levels that allow for unlimited use and unrestricted exposure (per the requirement

listed in the second bullet above).

2.0 Site ChronologyA chronology of significant site events and dates is included in Table 1, provided at the end of

the report text. Sources of this information are listed in Attachment 1, Documents Reviewed.

3.0 BackgroundThe Triangle Chemical Company site is located on a 2.3 acre tract on Texas State Highway (SH)

87 just north of Bridge City, Texas. The Triangle Chemical Company was in operation from the

early 1970's until 1981 (see Figure 1 for a site map). Various types of chemicals were handled at

the site, including industrial cleaning compounds, automotive brake fluid, windshield washer

solvent, hand cleaners, and pesticides. The raw materials and finished products were stored at the

site in surface storage tanks and 55 gallon drums (EPA, 1985). Waste management practices at

the site were poor, and contamination at the site resulted from discharges from deteriorated

drums and spills and leaks from drums and tanks (EPA, 1994a). The site is not associated with

any other Superfund sites (EPA, 1985).

Currently, the site is vacant, and it does not appear that any plans for future use exist. The

Triangle Chemical Company buildings remain onsite, but they are in a state of significant

disrepair, and one building has collapsed. The area around the site was originally reported as

mostly agricultural (Weston, 1984); observations made during the site inspection indicate the

land use immediately surrounding the site is currently mixed commercial and residential. A

residence is located immediately south of the site on SH 87. Across SH 87 are several small

businesses and residences. A commercial property, which is for sale, is located north of the site

on SH 87.



The site is located within the 100 year flood plain, and the site reportedly floods approximately

once every six years. Coon Bayou borders the site to the northwest. The shallow, contaminated

aquifer has been deemed unusable, but the next lower aquifer could be used as a potential water

supply (Weston, 1989b). The primary aquifers used for drinking water in the area are the Chicot

and Evangeline aquifers, which are at depths of over 100 feet in the area (Weston, 1984).

Groundwater monitoring has so far indicated that the lower unit is not contaminated (Intera,

1999).

The Texas Department of Water Resources (TDWR), predecessor to the Texas Water

Commission (TWC) and the Texas Natural Resources Conservation Commission (TNRCC),

initiated their involvement at the site in 1981. Initial investigations indicated that seven fish kills

over a six year period (March 1976 - October 1982) in the Coon Bayou were the result of

discharges of hazardous waste from the facility. In August 1981, TDWR acquired an injunction

against Triangle Chemical Company to achieve compliance with pollution control laws and to

prevent further discharges from the site, and in October 1981, TDWR found the site abandoned.

EPA initiated an Immediate Removal Action in April 1982 to prevent access to the site and to

dig a canal that would prevent runoff from reaching the highway. A Planned Removal Action

was conducted in August 1982 to remove drums and contaminated soil. In March of 1985, an

Emergency Action was conducted by EPA to install a fence around the entire site to prevent

unauthorized access and vandalism, which had been observed (EPA, 1994a).

The Triangle Chemical Company site was added to the National Priorities List (NPL) on

December 30, 1982. A Remedial Investigation (RI) was conducted between August 1983 and

April 1984. The RI results indicated that soil contamination was limited to the drum and tank

storage areas, to depths ranging between 1.0 and 6.5 feet (EPA, 1994a). The soil was determined

to be extensively contaminated with volatile organic compounds (VOCs). Several shallow

groundwater monitoring wells at the site indicated that the groundwater was slightly



contaminated, and Coon Bayou was also determined to be slightly contaminated (Weston, 1985).

The three onsite wells installed during the RI were designated MW-1, MW-2, and MW-3.

Weston conducted a pilot study in February 1985 as part of the Feasibility Study (FS), and

concluded that mechanical aeration was an effective means of treating the contaminated soils

(Weston, 1985). The Record of Decision (ROD), signed in June 1985, selected mechanical

aeration as the remedy for the soil contamination (EPA, 1985). The ROD concluded that the

principle threats posed by the site were the continued deterioration of storage tanks and drums

resulting in continued releases of hazardous materials, direct exposure to contaminants and

contaminated soils, and further degradation of groundwater and surface water quality due to soil

leaching and surface water erosion and runoff (EPA, 1985), and also required groundwater

monitoring, fence repair, and landscaping as part of Operations and Maintenance (O&M) for the

remedy (groundwater monitoring was to be from the three existing onsite monitor wells). During

the remedial action, MW-2 was decommissioned, and replaced with new monitor well MW-4.

Further details of the remedial action are provided in Section 4 of this review.

During the first year of quarterly O&M groundwater monitoring after completion of the remedial

action, samples from MW-4 demonstrated contamination at higher levels than previously

detected in the other onsite wells. It was concluded that MW-4 might have been contaminated

during construction, and in April 1988, MW-4 was decommissioned and replaced with new

monitor wells MW-5 and MW-6 (Weston, 1989a). Subsequent analysis of these wells, however,

confirmed the contamination demonstrated by MW-4 (Weston, 1989a).

A supplemental groundwater investigation was conducted from December 1988 through May

1989 to evaluate the extent of this contamination (Weston, 1989b). The investigation included a

cone penetrometer survey of the site, installation of additional monitor wells in the shallow and

deeper aquifer, collection and analysis of groundwater samples from two cone penetrometer

locations, all monitor wells, and two residential wells in the vicinity, and hydrogeologic testing

TC 5YR_000928.WPD PAGE 6 OF 18 SEPTEMBER 2000


and groundwater modeling. The investigation concluded the presence of significant VOC

contamination was limited to the area of MW-5 and MW-6 (up to 630 parts per billion [ppb]

methylene chloride and 3500 ppb 1,1-dichloroethene), with some lower level contamination (up

to 310 ppb chlorobenzene) detected in new monitor well MW-11 (located on the adjacent

property to the north). One indicator constituent was detected in the well installed in the deeper

aquifer (MW-7) (EPA, 1994b). Evaluation of groundwater transport as part of this study

concluded the flow directions are northwest and/or north-northeast (variable), the northwest flow

direction was impeded by a pinching out of the upper zone, and the north-northeast flow

direction would result in transport of contamination only about 100 feet onto the neighboring

property after 70 years (Weston, 1989b). The report recommended the four new shallow wells

(MW-8, MW-9, MW-10, and MW-11) and the new deep well (MW-7) be included in the

quarterly O&M sampling program for two years for determination of the need for further action,

and that if contamination in the deeper well was found to increase, the neighboring residential

wells be included in the sampling program (Weston, 1989b). No detections have been reported in

MW-7 since that initial sample. For the past few years, shallow wells MW-1, MW-3, MW-5,

MW-6, MW-8, MW-9, MW-10, and MW-11 and deep well MW-7 have been sampled semi-

annually; MW-1, MW-3 and MW-9 were dropped from the program after the last sampling event

in 1998, due to lack of detections.

The remedy selection process, remedy implementation, O&M activities, and progress since the

last five year review are summarized in the following paragraphs.

4.0 Remedial ActionsThe remedial action completed at the Triangle Chemical Company site included off-site

incineration and deep well injection of tank and drum contents, decontamination of onsite

structures, offsite disposal of trash and contaminated debris, mechanical aeration of contaminated

soil to remove VOC concentrations to background levels, and groundwater monitoring for a five

TC 5YR 000928.WPD PAGE 7 OF 18 SEPTEMBER 2000


year period. A fence was required to restrict access at the site (EPA, 1985). Included in this

section is a description of the remedy selection process employed at the Triangle Chemical

Company site, the implementation of the remedy, the operations and maintenance (O&M), and

the progress made at the site since the previous five year review.

4.1 Remedy SelectionThe ROD for the Triangle Chemical Company site was signed on June 11, 1985. The remedial

objectives were to remove and dispose of the contents of the storage tanks and drums,

decontaminate the tanks, drums, and on-site structures, prevent further significant contamination

of the shallow groundwater and surface water, reduce soil contamination to limit future impacts

to human health, the environment, and future site development, and remove and dispose of trash

at the site. The selected remedy for the Triangle Chemical Company site included the

incineration and deep well injection of the tank and drum contents. On-site structures were to be

decontaminated, and trash and contaminated debris at the site were to be disposed of off-site.

Contaminated soils were to be decontaminated to background concentrations using mechanical

aeration. The ROD also called for site landscaping, fence inspection and repair, and five years of

groundwater monitoring (EPA, 1985).

4.2 Remedy ImplementationThe TWC awarded the Remedial Action (RA) contract to ENSCO Services in August 1986, and

cleanup activities began on January 13, 1987. Mechanical aeration of the soils was performed

through tilling. The contents of the tanks and drums were analyzed and classified for proper

disposal. The buildings, process equipment, and tanks left onsite were decontaminated using a

triple rinse process. The final inspection was conducted on March 12, 1987, and the cleanup was

documented in Weston's June 1987 Remedial Action Close Out Report and the EPA's

September 1990 Site Interim Closure Report (EPA, 1994).



4.3 Operations and Maintenance

O&M activities at the site, including groundwater monitoring and site inspections and mowing,

have been conducted at the site since 1987. During the first year of O&M groundwater sampling,

MW-1, MW-3, and MW-4 were sampled. MW-4 was found to have higher concentrations than

previously demonstrated in other wells, and it was decommissioned and replaced with MW-5 and

MW-6. Sampling of these new wells confirmed the groundwater contamination documented in

MW-4, and a supplemental groundwater investigation was conducted from December 1988

through May 1989 (Weston, 1989b).

This supplemental investigation found that shallow groundwater was contaminated to a greater

extent than initially thought, and that the deeper aquifer showed one detection of an indicator

constituent. The shallow groundwater was not deemed usable due to native conditions, but the

deeper aquifer qualified as a potential drinking water source. The investigation showed that a 15

foot clay layer separated the two aquifers, however, and a pump test demonstrated that no

communication existed between the shallow and deeper aquifers. Modeling showed future

potential contaminant migration to be minimal and impeded by Coon Bayou, and a risk

assessment showed the low levels of contamination in Coon Bayou did not pose a risk. The

supplemental investigation concluded that monitored natural attenuation was the appropriate

course of action for the observed groundwater contamination (Weston, 1989b).

The TNRCC is currently responsible for O&M activities at the site, which include semi-annual

site inspections and groundwater sampling and analysis. The site is also required to be mowed as

necessary. Quarterly inspections and groundwater sampling were originally required at the site;

semi-annual inspection and groundwater sampling events have been conducted since at least as

far back as 1993 (per groundwater data included in the latest O&M report, dated May 1999).

The May 1999 O&M report is the latest available O&M report and covers activities at the site

conducted September 1998 through May 1999. The report concluded that groundwater



contamination at the site was not migrating, and that natural attenuation of the contamination has

been occurring in the upper aquifer. The lower aquifer had been determined to not be

contaminated (no contaminants were detected in MW-7 since the first sampling event). The

report notes that sections of the fence near monitoring well MW-8 had fallen down and were in

need of repair. Also, the report noted that vandalism had occurred at the site. Graffiti had been

spray-painted on the walls within several of the buildings, and several empty drums left onsite

after groundwater sampling activities had been moved (Intera, 1999). The fence damage and

graffiti were still present at the time of the second five year review inspection in August 2000.

Table 2 provides a summary of the annual O&M costs recorded to-date. See Section 6.3 for a

summary of projected versus actual annual O&M costs.

4.4 Progress Since First Five Year ReviewSince the first five year review dated July 1994, groundwater sampling events (and

corresponding site inspections) were conducted quarterly the first year, in November 1994

(Intera, 1994), February 1995 (Intera, 1995a), May 1995 (Intera, 1995b), and August 1995 (Intera

and Cook-Joyce, 1996a), and semi-annually thereafter, in May 1996 (Intera and Cook-Joyce,

1996a), July 1996 (Intera and Cook-Joyce, 1996b), April 1997 (Intera, 1997a), September 1997

(Intera, 1997b), March 1998 (Intera, 1998a), July 1998 (Intera, 1998b), February 1999 (Intera,

1999), and May 1999 (Intera, 1999).

Wells included in the groundwater sampling program events listed above are: MW-1, MW-3, and

MW-9 (each event through July 1998), and MW-5, MW-6, MW-7, MW-8, MW-10, and MW-11

(each event).

The first five year review recommended that warning signs be posted at the site (EPA, 1994);

these signs were added in November 1994 (Intera, 1994).



The first five year review report also concluded that the well in the deeper aquifer (MW-7)

should be sampled more frequently to verify the initial detection in that well. The well was added

to the groundwater sampling program, and was sampled in each of the events listed above. No

detections have been recorded since the initial detection.

In addition, the first five year report concluded that MW-8 and MW-9, both of which had only

been sampled once, should be sampled at least annually to confirm continued lack of

contamination in these perimeter wells. As a result, MW-8 has been sampled in each of the

groundwater sampling events listed above. Contamination was detected in samples from this well

during the 1996, 1997, 1998, and 1999 events; the May 1999 report concluded that seasonal

fluctuations in flow patterns resulted in the contamination of this well from the historically

downgradient onsite source (Intera, 1999). MW-9 was sampled in each event listed above until

July 1998; no confirmed detections have been reported in this well, and it was not sampled in

September 1998 or May 1999.

See Table 3 for a summary of the actions taken since the last five year review.

5.0 Five Year Review ProcessThis five year review has been conducted in accordance with EPA's Draft Comprehensive Five

Year Review Guidance, dated October 1999 (EPA, 1999), which encompasses the guidance

contained in existing final guidance documents. Interviews were conducted with relevant parties,

a site inspection was conducted at the site, and a review of applicable data and documentation

covering the period of the review was evaluated. The findings of the review are described in the

following section.

TC_5YR_000928.WPD PAGE 1 1 OF 18 SEPTEMBER 2000


6.0 Five Year Review FindingsThe information collected during the interviews, the site inspection, the standards review, and the

data review are described in the following subsections.

6.1 InterviewsDuring the course of this second five year review, interviews were conducted with one city

representative and one state representative. Interview Record Forms which document the issues

discussed during these interviews are provided in Attachment 2.

Interviews were conducted with Bill Denham of the City of Orange on August 9, 2000, at the

site, and with Emmanuel Ndame of the TNRCC by telephone on August 11, 2000. The overall

impression of the remedy effectiveness since the previous five year review was that the remedy is

still protective of human health and the environment. Both interviewees indicated they were

aware of no concerns about the site expressed by people in the local community.

6.2 Site InspectionA site inspection was conducted at the site on August 9, 2000. The completed site inspection

checklist is provided in Attachment 3. Photographs taken during the site inspection are provided

in Attachment 4.

No key for the gate lock was provided for the site inspection, so to gain access to the site for the

inspection one lock was cut off with bolt cutters. A replacement lock was installed and the keys

retained by EPA. The access gate is shown in Photograph 3 (Attachment 4).

As shown in Figure 1, the Triangle Chemical Company site is located on the west side of Texas

SH 87, just north of Bridge City, Texas. To the north of the site is a commercial property that

appeared to be for sale. South of the site appears to be a combined residence/commercial



property. West of the site is the Coon Bayou, which could not be directly observed during the site

inspection due to dense vegetation. The site did not appear to have been mowed yet this season

(Photographs 6, 9, 21,22).

Warning signs were observed to be present at several locations on the perimeter fence

(Photographs 2 and 5). The perimeter fence was observed to be damaged and/or missing in three

places: (1) near the eastern comer of the perimeter near MW-1 (Photographs 1, 2, and 8); (2) at

the southern comer of the perimeter, near the access gate (Photograph 4); and (3) along the

southwestern perimeter, near MW-8 (Photographs 25, 26, and 27). Near well MW-8, the fence

was completely down for about a 20 foot stretch. During his interview, Mr. Ndame/TNRCC

indicated the fence had been reported during one of the groundwater sampling events as damaged

by the adjacent property owners. Graffiti was observed on the walls inside several of the

buildings (Photographs 16 and 17), and one building, located behind the former office building

(Photograph 6) had collapsed. Several empty drums were observed to be staged inside former

Process Building No. 2 (Photograph 23) and former Process Building No. 1.

Each existing monitor well was visited and photographed during the site inspection. The outer

casing at MW-3 was open and the inner PVC casing was missing its cap (Photographs 17, 18, 19,

20). The outer casing of MW-8 was unlocked (the well location is illustrated in Photographs 25

and 26). Wells MW-5 and MW-6 had bent guard posts (Photographs 10, 11, 13, and 14). A used

bailer was observed on the floor adjacent to MW-9 (Photograph 15). From what could be

observed of the remaining wells, the outer casings, all locked except for the flush mount wells,

appeared to be in good condition (Photographs 7, 8, 12, 13, 23, and 24). Although unauthorized

site access is currently not restricted because of the damage to the perimeter fence, none of the

wells appeared to have been vandalized.



6.3 Review of O&M CostsAs part of the technical evaluation of this review, annual O&M costs were compared to original

projected O&M costs. In his interview, the TNRCC representative, Mr. Emmanuel Ndame,

indicated that he was unable to locate written O&M documentation available for the years 1997

through 2000, but he estimated cost for O&M in 2000 to be $19,300, and that this amount

appropriately reflected the annual O&M cost since 1997. Cost figures were available for August

1994 through July 1996, and the amount spent for this period was approximately $88,200. Table

2 summarizes the O&M costs since the first five year review.

The O&M plan estimated the annual O&M costs to be $11, 900 (based on 1986 costs) (Weston,

undated). This cost does not factor into account the additional wells added in 1989 at the site, nor

has it been adjusted for inflation. The only change to O&M at the site since the previous five year

review has been the switch from quarterly inspections and semi-annual monitoring to semi-

annual inspections and monitoring. This change resulted in a decrease in O&M costs.

6.4 Standards ReviewApplicable or Relevant and Appropriate Requirements (ARARs) for this site were identified in

the ROD dated June 11, 1985. This five year review included identification of and evaluation of

changes in these ARARs to determine whether such changes may affect the protectiveness of the

selected remedy.

The ROD identified the following ARARs as having an impact on the proposed remedy:

1. The Resource Conservation and Recovery Act (RCRA) substantive requirements for the

closure of tanks and container storage facilities, as regulated under 40 CFR Part 264.

2. Water quality criteria for human health and drinking water established under the Clean

Water Act.

TC_5YR 000928.WPD PAGE 14 OF 18 SEPTEMBER 2000


3. Air exposure limits established by the Occupational Safety and Health Administration

(OSHA).

4. Requirements to evaluate the potential impacts to flood plains as regulated under the

Executive Order on Floodplain Management, Executive Order No. 11988.

No state ARARs were identified in the ROD.

The first five year review for the Triangle Chemical Company also identified the Maximum

Contaminant Levels (MCLs) promulgated under the Safe Drinking Water Act as to-be-

considereds (TBCs) for the lower groundwater bearing unit at the site.

All tanks, containers, and associated hazardous substances have been removed from the site. Soil^

contamination was remediated to background concentrations. Since no hazardous wastes remain

on-site, the requirements under RCRA no longer apply.

No changes have occurred to Executive Order No. 11988 or the Clean Water Act which would

call into question the effectiveness of the remedy. The lower groundwater bearing unit is not

known to be used, and no contamination has migrated into the aquifer. No changes have occurred

to the MCL requirements since the first five year review.

Although OSHA air exposure limits no longer apply to the site remedy, groundwater monitoring

is still occurring at the site, and OSHA requirements related to groundwater sampling would be

applicable requirements for the site. These requirements are addressed under the site-specific

health and safety plan.

In summary, it appears that no new laws or regulations have been promulgated or enacted that

would call into question the effectiveness of the remedy at Triangle Chemical Company to

protect human health and the environment.



6.5 Data ReviewData collected since the previous five year review includes all the groundwater sampling results

and water level measurements made since July 1994. Table 4 summarizes the detections in

groundwater samples collected in November 1994 vs. July 1998 and May 1999.

In the most recently documented events, February and May 1999, six monitoring wells, MW-5,

MW-6, MW-7 (deeper aquifer), MW-8, MW-10, and MW-11 were sampled (Intera, 1999).

These wells have been sampled in each event since the last five year review. Monitoring wells

MW-1, MW-3, and MW-9, considered to be outside the shallow aquifer plume boundary, were

last sampled in July 1998 (Intera, 1998a). Wells MW-3 and MW-9 are the wells closest to Coon

Bayou, on the western side of the site; MW-1 is located at the eastern perimeter near SH 87. The

groundwater gradient has been historically documented as radial away from wells MW-6 and

MW-8 (located central to the site) or towards the east (Intera, 1997 through 1999, and Intera,

Inc., and Cook-Joyce, Inc., 1994 through 1996).

Historically, the most contaminated samples have been collected from MW-6. The analytical

results show that the concentrations of most contaminants appear to be attenuating in MW-6

(Table 4). Benzene concentrations have remained fairly stable since the previous five year

review. The last monitoring report indicated the plume is not migrating (Intera, 1999), but this is

not confirmed, since the perimeter unaffected wells MW-1, MW-3, and MW-9 have not been

sampled since July 1998.

Sampling has been conducted in 2000, but the results were not available for this review.

7.0 AssessmentBased on the site interviews, the site inspection, and the data review, it appears the remedy is still

functioning as intended by the ROD. The assumptions used at the time of remedy selection are



still valid. However, several deficiencies which do not currently affect the protectiveness of the

remedy should be addressed to ensure continued protectiveness. These are reinstating regular (at

least annually) sampling of perimeter wells MW-1, MW-3, and MW-9, repairs to the perimeter

fence, and unlocked/uncapped wells.

8.0 DeficienciesThe deficiencies noted during the site inspection and data review are listed in Table 5. None of

these deficiencies currently affect the protectiveness of the remedy, but addressing them is

necessary to ensure continued protectiveness.

9.0 Recommendations and Follow-up ActionsTo restrict access to the site and maintain the integrity of the monitoring system, repairs should

be made to the perimeter fence, and a lock needs to be placed on well MW-8. The lid to the outer

casing of well MW-3 needs to be repaired so that the well can be locked, and a cap needs to be

put on the PVC well casing. Mowing should be re-initiated to control the height of the grass at

the site. Wells MW-1, MW-3, and MW-9 should be reincorporated into the groundwater

sampling program, for sampling at least annually to confirm lack of migration of the plume. Five

year reviews should continue until concentrations of contaminants have attenuated to levels that

will allow for unrestricted use at the site.

10.0 Protectiveness StatementBecause the remedial actions implemented at the Triangle Chemical Company site continue to be

protective, the remedy for the site continues to be protective of human health and the

environment.

TC_5YR_000928.WPO PAGE 17 OF 18 SEPTEMBER 2000


11.0 Next ReviewThe next five year review should be completed on or before August 2005. This review should

include an inspection and update on the condition of the fence and monitor well network, as well

as a data review of all groundwater monitoring that has occurred since this five year review to

ensure appropriate actions recommended under this five year review have been implemented and

that O&M continues as required.


F^urfiL 1; Sl+& M&.p

Ci produxed -Prow J'/r/'ero 'W]

TRIANGLE CHEMICAL COMPANY SITESECOND FIVE YEAfl REVIEW REPORT



TRIANGLE CHEMICAL COMPANY SITESECOND FIVE-YEAR REVIEW REPORT

Table 1Chronology of Site Evci

DateMarch 1976 - October 1982

August 1981

October 1981

April 1982

August 1982

August 1983

April 1984

August 1984 - March 1985

February 1985

March 1985

June 11,1985

January 2, 1987

January 13, 1987

March 12, 1987

June 1987

October 1989

September 1990

July 1994

August 2000

ntsEvent

TDWR documented seven fish kills in waters near the Triangle ChemicalCompany site.

TDWR acquired a temporary injunction against Triangle Chemical Company toattain compliance with pollution control laws and to prevent further dischargesfrom the site.

TDWR found the site abandoned.

The EPA initiated an Immediate Removal Action to deter public access tohazardous materials at the site. The actions taken included the installation ofsecurity fencing around the drum storage area, the posting of warning signs, andthe creation of a drainage canal to prevent contaminated surface water runofffrom reaching the highway in front of the site.

A Planned Removal Action was undertaken by EPA to remove drums,contaminated soil, and contaminated debris from the site.

A Cooperative Agreement was signed by the EPA and the State of Texas thatgave the state lead responsibilities to conduct the RI/FS.

The RI was completed (issued in August 1984).

The FS was conducted

A pilot study was conducted by the state contractor, R. F. Weston, to determine ifmechanical aeration would effectively treat the soils at the site.

third Emergency Action conducted, to enclose the site within a security fence.

The Record of Decision was signed.

Notice to Proceed with the RA was given to the state contractor, ENSCO

ENSCO mobilized to the site.

Final RA inspection conducted at the site.

Final Remedial Action Close Out report (prepared by Weston).

Supplemental Groundwater Monitoring Final Report (prepared by Weston).

EPA issued the Site Interim Close Out report

First Five-Year Review Report issued by EPA

O&M groundwater sampling and site inspections continue semi-annually(includes sampling of MW-1, MW-3, and MW-6 through MW-11.

TC 5YR 000928_TABLES.WPD PAGE 1 OF 5 SEPTEMBER 2000


Table 2Annual O&M Costs Sin

DcFrom

August 1994

1997

ce Last Five-Year Reviewates

ToJuly 1996

2000

Total Cost rounded to nearest $100

$88,200

Cost estimated by TNRCC is$19,200 annually since 1997

Table 3Actions Taken i

Deficienciesfrom Previous

Review

Detection ofCOCs in MW-7in 1993 O&Mevent should beverified.

MW-8 andMW-9 had onlybeen sampledonce

Warning signsmissing

Continue five-year reviews

Since Last Five-YeaRecommendations/Follow-up Actions

Sample MW-7quarterly or semi-annually until non-detect orcontaminationverified.

Sample thesewells at leastannually

Replace thewarning signs

N/A

»r ReviewParty Responsible

TNRCC

TNRCC

TNRCC

EPA

MilestoneDate

N/A

N/A

N/A

July 1999

Action Taken

All wells sampledquarterly first yearafter five-yearreview, and semi-annually since1996

All wells sampledquarterly first yearand semi-annuallysince 1996

New warningsigns were posted

Second five-yearreview conducted

Date ofAction

Semi-annuallysince 1996

Semi-annualsince 1996

Nov. 10,1994

August 2000

TC_5YR_000928_TABLES.WPD PAGE 2 OF 5 SEPTEMBER 2000

TRIANGLE CHEMICAL.COMPANY SITESECOND FIVE-YEAR REVIEW REPORT

Table 4Selected Groundwater Detectio

Contaminant

Acetone

Benzene

Chlorobenzene

Chloroethane

1,2-Dichlorobenzene

1,4-Dichlorobenzene

1,1-Dichlorethane

1,2-Dichloroethane

1,1-Dichloroethene

cis-1,2-Dichloroethene1

trans-1,2-Dichloroethene

Tetrachloroethene

)ns Since LasWell

MW-6

MW-6

MW-10

MW-6

MW-5

MW-10

MW-11

MW-6

MW-6

MW-5

MW-11

MW-6

MW-5

MW-11

MW-6

MW-11

MW-6

MW-8

MW-6

MW-6

MW-6

MW-8

MW-9

MW-10

t Five-year Review1994 (Nov.)

Concentration(PPb)

29

27

ND

317

195

78

473

424

NA

NA

NA

NA

NA

NA

143

NA

39

68

80

NA

11

133

ND

ND

/

1998 (July)Concentration

(PPb)NA

22

ND

242

54

85

170

66

12

240

15

10

31

26

123

5

25

33

89

8

24 J

112

8J

6J

1999 (May)Concentration

(PPb)748

23

7

206

47

103

253

59

12

174

ND

9

25

45

49

ND

ND

37

38

7

8

118

NA

ND



Table 4Selected Groundwater Detectic

Contaminant

Toluene

Trichloroethene

Vinyl Chloride

1 : total dichloroethene for 1994 results

ins Since Las

Well

MW-6

MW-6

MW-6

MW-11

only.

it Five-year Review1994 (Nov.)

Concentration(PPb)

10

89

48

14

V

1998 (July)Concentration

(PPb)

14

86

47

ND

1999 (May)Concentration

(PPb)

10

27

40

ND

Table 5Currently-Identified De

Fence is damaged at three

Grass needs mowing.

Wells MW-3 and MW-8 n

Well MW-3 needs a PVC

Wells MW-1, MW-3, andprogram to provide a "clea

ficienciesDeficiencies

locations.

eed well cap locks on the outer casings.

well cap on its inner casing.

MW-9 should be added back to the monitoringm" line for contaminant plume tracking.

Currently AffectsProtectiveness

(Y/N)

N

N

N

N

N



Table 6Recommendations ar

Deficiencies

Fence is damaged atthree locations.

Grass needs mowing.

Wells MW-3 andMW-8 need locks onthe outer casings.

Well MW-3 needs aPVC well cap on itsinner casing.

Wells MW-1, MW-3,and MW-9 should beadded back to themonitoring program toprovide a "clean" linefor contaminant plumetracking.

1. Although performancthemselves, they are req

nd Follow-up Actions

Recommendations/Follow-up Actions

Repair fence

Mow site on regularbasis.

Add locks to MW-3and MW-8

Add well cap to MW-3

Include MW-1, MW-3, and MW-9 insampling, at leastannually

e of these activities will nuired to allow appropriate

PartyResponsible

TNRCC

TNRCC

TNRCC

TNRCC

TNRCC

ot directly affectmonitoring to en

OversightAgency

EPA

EPA

EPA

EPA

EPA

the protectiversure the rernei

MilestoneDate

December2000

asneededly

December2000

December2000

December2001,ornextsamplingevent.

ness of the reiry continues to

Follow-upActions:Affects

Protectiveness(Y/N)N'

N

N'

N'

N'

nedy in and/ofbe protective.

PAGE 5 OF 5 SEPTEMBER 2000


Attachment 1

Documents Reviewed



Attachment 1Documents Reviewed

Intera, Inc., and Cook-Joyce, Inc., 1994. Quarterly Groundwater Data and Operations andMaintenance at the Triangle Chemical Company Federal Superfund Site for the periodOctober 1994 through December 1994. Revision 2, April 1995.

Intera, Inc., and Cook-Joyce, Inc., 1995a. Quarterly Groundwater Data and Operations andMaintenance at the Triangle Chemical Company Federal Superfund Site for the timeperiod January 1995 through March 1995. May 1995.

Intera, Inc., and Cook-Joyce, Inc., 19950. Quarterly Groundwater Data and Operations andMaintenance at the Triangle Chemical Company Federal Superfund Site for the timeperiod April 1995 through June 1995. July 1995.

Intera, Inc., and Cook-Joyce, Inc., 1996a. Biannual Groundwater Data and Operations andMaintenance at the Triangle Chemical Company Federal Superfund Site. May 1996.

Intera, Inc., and Cook-Joyce, Inc., 1996b. Biannual Groundwater Data and Operations andMaintenance at the Triangle Chemical Superfund Site. August 1996.

Intera, 1997a. Operations and Maintenance Activity Report for the Triangle Chemical CompanyFederal Superfund Site. April 1997.

Intera, 19970. Operations and Maintenance Activity Report for the Triangle Chemical CompanyFederal Superfund Site. September 1997.

Intera, 1998a. Operations and Maintenance Activity Report for the Triangle Chemical CompanyFederal Superfund Site. March 1998.

Intera, 19980. Operations and Maintenance Activity Report for the Triangle Chemical CompanyFederal Superfund Site. July 1998.

Intera, 1999. Operations and Maintenance Activity Report for the Triangle Chemical CompanyFederal Superfund Site: Annual Report, September 1998 - May 1999. May 1999.

U.S Environmental Protection Agency (EPA), 1985. Record of Decision, Remedial ActionAlternative. Final, June 11, 1985.

TC_5YR_000928_ATT1_DOCUMENTS.WPD PAGE 1 OF 2 SEPTEMBER 2000


U.S. Environmental Protection Agency (EPA), 1990. Site Interim Close Out Report. September1990.

U.S. Environmental Protection Agency (EPA), 1991. Structure and Components of Five-YearReviews. Office of Solid Waste and Emergency Response (OSWER) Directive 9355.7-02. May 23, 1991.

U.S. Environmental Protection Agency (EPA), 1991. Factsheet: Structure and Components ofFive-Year Reviews. OSWER Directive 9355.7-02FS1. August 1991.

U.S. Environmental Protection Agency (EPA), 1994a. 1st Five -Year Review, Triangle ChemicalCompany Superfund Site, Bridge City, Orange County, Texas. Final, July 1994.

U.S. Environmental Protection Agency (EPA), 1994b. Supplemental Five-Year ReviewGuidance. OSWER Directive 9355.7-02A. July 26, 1994.

U.S. Environmental Protection Agency (EPA), 1995. Second Supplemental Five-Year ReviewGuidance. OSWER Directive 9355.7-03A. December 21, 1995.

U.S. Environmental Protection Agency (EPA), 1999. Comprehensive Five-Year ReviewGuidance. EPA540R-98-050, OSWER Directive 9355.7-03B-P. Draft, October 1999.

Weston, 1984. Site Investigation, Triangle Chemical Company, Bridge City, Texas. Final,September 1984.

Weston, 1985. Feasibility Study, Triangle Chemical Company, Bridge City, Texas. Final, June1985.

Weston, 1987. Remedial Action Closeout Report. June 1987.

Weston, 1989a. Groundwater Sample Data for Triangle Chemical Company Remedial ActionOperation and Maintenance (2nd Year). June 1989.

Weston, 1989b. Triangle Chemical Company Superfund Site Supplemental GroundwaterMonitoring Final Report. Final, October 1989.

Weston, undated. Operation and Maintenance Plan for Triangle Chemical Co. Remedial Action.

TC_5YR_000928_An1 _DOCUMENTS.WPD PAGE 2 OF 2 SEPTEMBER 2000


Attachment 2

Interview Record Forms




TC 5YR_000928.WPD SEPTEMBER 2000

Five-Year RevTriangle ChemOrange County

Site Name

Triangle ChemicaSuperfund Site

InterviewContactsMargaret 0'Hare

Dan-en Davis

Interview Que

1. What isfirst five

Response:

2. From yocommun

Response:

3. Are you

Response:

4. Are youdumpin

Response:

5. Havethactivitiedescribe

Response:

iew Interview Rical Company Sit, Texas

Company

Organization

CH2M HILL, asrepofEPA

CH2M HILL, asrepofEPA

stions

your overall impreyear review)?

So impression note

ur perspective, whlity?

Mr. Denham indicaabout the site.

aware of any comr

No concerns report

aware of any evens,, vandalism, trespa

Mr. Denham indies

ere been routine cos, etc.) conducted bpurpose and result

Mr. Denham indice

ecorde

EPAID

EPAID#1

Phone

972-980-2170

972-980-2170

ssion of the

;d.

at effect ha

ited that the

Tiunity cone

ed.

ts, incidentissing, or ei

ited he was

mmunicatic)y your offis.

ited he was

Interviewee: Bill DDepart

No.

DCD055143705

Email

[email protected]

[email protected]

work conducted at the s

s the site since that time

;re appears to be no inter

;ems regarding the site o

s, or activities that have (mergency response from

not aware of any such e

3ns or activities (site visice, if applicable, regard!

not aware of any routine

enham/Orangetment of Public

Date ofInterview

August 9,2000

Address

5339 Alpha RoadDallas, Texas 752

5339 Alpha RoadDallas, Texas 752

ite since 1994 (t

"lad on the surro

est expressed b}

r its administrat

occurred at the slocal authoritie

vents, incidents

ts, inspections,ng the site? If s

s communicatio

County= Works

InterviewMethod

In person

Suite 30040

Suite 30040

he date of the

unding

y the community

ion?

site, such ass?

or activities.

reportingo, please

ns or activities.

TC 5YR 000928_ATT2JNTERVIEWRECORD_ClTY.WPD PAGE 1 OF 2 AUGUST 9,2000

Interview Questions

1. What is your overall impression of the work conducted at the site since 1994 (the date of thefirst five year review)?

Response: No impression noted.

2. From your perspective, what effect has the site since that time had on the surroundingcommunity?

Response: Mr. Denham indicated that there appears to be no interest expressed by the communityabout the site.

3. Are you aware of any community concerns regarding the site or its administration?

Response: No concerns reported.

4. Are you aware of any events, incidents, or activities that have occurred at the site, such asdumping, vandalism, trespassing, or emergency response from local authorities?

Response: Mr. Denham indicated he was not aware of any such events, incidents, or activities.

5. Have there been routine communications or activities (site visits, inspections, reportingactivities, etc.) conducted by your office, if applicable, regarding the site? If so, pleasedescribe purpose and results.

Response: Mr. Denham indicated he was not aware of any routine communications or activities.

TRIANGLE CHEMICAL FIVE-YEAR REVIEW INTERVIEW RECORDRESPONSE PROVIDED BY BILL DENHAM/ORANGE COUNTY DEPARTMENT OF PUBLIC WORKS

6. Have there been any complaints, violations, or other incidents related to the site that required aresponse by your office, if applicable? If so, please give details of the events and results of theresponses.

Response: Mr. Denham indicated he was not aware of any complaints, violations, or otherincidents.

7. Do you feel well-informed about the site's activities and status?

Response: Mr. Denham indicated he felt as aware as he needed to be about the site.

8. Do you have any comments, suggestions, or recommendations regarding the site?

Response: Mr. Denham indicated he had no comments, suggestions or recommendations.

TC_5YR_000928_ATT2_lNTERVIEWRECORD_ClTY.WPD PAGE 2 OF 2 AUGUST 9,2000

Five-Year Review Interview RecordTriangle Chemical Company SiteOrange County, Texas

Interviewee: Emmanuel Ndame/TNRCCPhone: #512-239-2494email: [email protected]

Site Name EPA ID No. Date ofInterview

InterviewMethod

Triangle Chemical CompanySuperfund Site

EPA ID#TXD055143705 August 10,2000

via phone

InterviewContacts

Organization Phone Email Address

Margaret 0'Hare CH2M HILL, asrep ofEPA

972-980-2170

[email protected] 5339 Alpha Road Suite 300Dallas, Texas 75240

Darren Davis CH2M HILL, asrep ofEPA

972-980-2170

[email protected] 5339 Alpha Road Suite 300Dallas, Texas 75240

Interview Questions

1. What is your overall impression of the work conducted at the site? (general sentiment)

Response: Mr. Ndame indicated that natural attenuation appears to be occurring for mostcontaminants. The results for MW-7 still show no contamination in the lower aquifer,and there are no indications that the site poses unacceptable risks to human health andthe environment.

2. From your perspective, what effect have remedial operations at the site had on the surroundingcommunity?

Response: Mr. Ndame responded that no effect was apparent.

3. Are you aware of any ongoing community concerns regarding the site or its operation andadministration? Please provide details.

Response: No concerns noted.

4. Are you aware of any significant events, incidents, or activities that have occurred at the site,such as dumping, vandalism, trespassing, or emergency response from local authorities? If so,please give details.

Response: Mr. Ndame indicated the fence near MW-8 had been damaged by the neighbors whilethey were doing some excavating. He stated that they were suppose to repair thefence, and he was not aware until this interview that the repairs had not been made.

PAGE 1 OF 3 AUGUST 10,2000

TRIANGLE CHEMICAL FIVE-YEAR REVIEW INTERVIEW RECORDRESPONSE PROVIDED BY EMMANUEL NDAME/TNRCC

5. Have there been routine communications or activities (site visits, inspections, reportingactivities, etc.) conducted by your office regarding the site? If so, please describe purpose andresults.

Response: The only routine activities at the site are the semi-annual monitoring events and siteinspections. The state contractor writes a report that summarizes the results.

6. Have there been any complaints, violations, or other incidents related to the site that required aresponse by your office? If so, please give summarize the events and results of the responses.

Response: No complaints, violations, or other incidents noted.

7. Were any problems or difficulties encountered after the initiation of remedial action whichimpacted construction progress and implementability? Please briefly summarize theproblems/difficulties.

Response: No response provided.

8. Were or have any problems been encountered at either site which required or will requirechanges in the Record of Decision or remedial action performed? (Brief summary)

Response: No problems noted.

9. Have there been any significant changes in the site status or maintenance requirements sincecompletion of remedial action? If so, do they affect the protectiveness or effectiveness of theremedy? Please describe changes and impacts.

Response: No changes noted.

10. Have there been opportunities to optimize the operation, maintenance, or sampling efforts atthe site since the start of the remedial action? Please describe changes and the resultant ordesired cost savings or improved efficiency

Response: No opportunities noted.

11. What is the status of groundwater monitoring?

Response: The site was visited in February 2000, and the monitoring wells were sampled.Another sampling event is scheduled for later in the year. The contractorsubmits one report for the year that summarizes the groundwater monitoring.

TC_5YR_000928_ATT2_INTERVIEWRECORD_TNRCC.WPO PAGE 2 OF 3 AUGUST 10,2000

TRIANGLE CHEMICAL FIVE-YEAR REVIEW INTERVIEW RECORDRESPONSE PROVIDED BY EMMANUEL NDAME/TNRCC

12. What are the O&M costs related to the site? Have you noticed any significant changesin the O&M costs?

Response: Mr. Ndame reported the O&M costs for the current year will be $ 19,281, andthat this amount is a good approximation of the annual costs since semi-annualmonitoring began. He also noted the costs have gone down since themonitoring went from quarterly to twice a year in 1997.

13. Do you have any comments, suggestions, or recommendations regarding the site?

Response: No comments, suggestions, or recommendations noted.

TC_5YR_000928_An2_lNTCRVlEWRECORD_TNRCC.WPD PAGE 3 OF 3 AUGUST 10,2000



TC 5YR 000928.WPD SEPTEMBER 2000


Attachment 3

Site Inspection Checklist


Triangle Chemical CompanyFive-Year Review Site Inspection Checklist

Please note that "O&M" is referred to throughout this checklist. At sites where Long-TermResponse Actions are in progress, O&M activities may be referred to as "system operations"since these sites are not considered to be in the O&M phase while being remediated under theSuperfund program. N/A means "not applicable."

I. SITE INFORMATION

Site Name: Triangle Chemical Company EPAID:TXD055143705

City/State: near Bridge City, Orange County, Texas Date of Inspection: August 9,2000

Agency Completing 5 Year Review: EPA Weather/lemperature: Partly Cloudy, 90° F

Remedy Includes: (Check all that apply)a Landfill cover/containmentB Access controlsa Institutional controlsg Groundwater pump and treatmentD Surface water collection and treatments Other: Monitored Natural Attenuation

Attachments: s Inspection team roster attached B Site map attached

INTERVIEWS (Check all that apply)

1. O&M site manager: TNRCCName: Emmanuel NdameTitle: RPMDate: August 11,2000Interviewed: a at siteProblems, suggestions:

a at office a by phone Phone Number: 512-239-2494a Additional report attached (if additional space reguired).

Attachment 2 to the Five-Year Review.

2. O&M staff:Name:Title:Date:Interviewed: o at siteProblems, suggestions:

o at office a by phone Phone Number:a Additional report attached (if additional space required).

PAGE 1 OF 13 SITE INSPECTION AUGUST 9,2000

TRIANGLE CHEMICAL COMPANY SITESECOND FIVE-YEAR REVIEW SITE INSPECTION CHECKLIST

3. Local regulatory authorities and response agencies (i.e., State and Tribal offices, emergency response office, policedepartment, office of public health or environmental health, zoning office, recorder of deeds, or other city and countyoffices, etc.) Fill in all that apply.

Agency: City of OrangeContact:Name: Bill DenhamTitle:Date: August 9,2000Phone Number: 409-883-1900Problems, suaaestions: a Additional report attached {if additional space required).Attachment 2 to the Five-Year Review.

Agency:Contact:Name:Title:Date:Phone Number:Problems, suqqestions: a Additional report attached (if additional space required).

Agency:Contact:Name:Title:Date:Phone Number:Problems, suaqestions: D Additional report attached (if additional space required).

Agency:Contact:Name:Title:Date:Phone Number:Problems, suqqestions: a Additional report attached (if additional space required).

4. Other interviews (optional) a N/A a Additional report attached (if additional space required).

TC_5YR_000928_ATT3A_SlTElNSPECTIONCHECKLIST.WPD PAGE 2 OP 13 SITE INSPECTION AUGUST 9,2000


1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

III.ONSITEDOCUME

O&M Documentsg O&M Manuala As-Built Drawingso Maintenance LogsRemarks:

Health and Safety Plan Documentsa Site-Specific Health and Safety Plano. Contingency plan/emergency responseRemarks:

O&M and OSHA Training RecordsRemarks:

Permits and Service Agreementsa Air discharge permita Effluent dischargeD Waste disposal, POTW^ Other permitsRemarks:

Gas Generation RecordsRemarks:

Settlement Monument RecordsRemarks:

Groundwater Monitoring RecordsRemarks:

Leachate Extraction RecordsRemarks:

Discharge Compliance RecordsRemarks:

Daily Access/Security LogsRemarks:

:NTS

0D

g

plan

& RECORDS VERIFIEC

Readily availableReadily availableReadily available

a. Readily availableo Readily available

D Readily available

o Readily availablea Readily availableo Readily availableD, Readily available

a Readily available

Q Readily available

a Readily available

5 Readily available

a Readily available

D Readily available

) (Check all that ap

a Up to datea Up to datea Up to date

n. Up to datea Up to date

D Up to date

a Up to datea Up to daten Up to dateg. Up to date

g Up to date

a. Up to date

a Up to date

a Up to date

5 Up to date

n Up to date

ply)

HN/ABN/ABN/A

BN/ABN/A

aN/A

BN/ABIN/ABN/ABN/A

BN/A

BN/A

aN/A

BN/A

HN/A

BN/A

TC_5YR_000928_ATT3A SiTElNSPEC-nONCHECKLIST.WPD PAGE 3 OF 13 SITE INSPECTION AUGUST 9,2000


IV. O&M Costs s Applicable

1. O&M OrganizationB State in-housen PRP in-housen Other:

a Contractor for Statea Contractor for PRP

2. O&M Cost Recordss Readily available o Up to dateOriginal O&M cost estimate:

a Funding mechanism/agreement in places Breakdown attached [see Table 2 of Five-Year Review Report]

From (Date):

From (Date):

From (Date):

From (Date):

From (Date):

Total annual cost by year for review period if available

To (Date): Total cost: g Breakdown attached

To (Date): Total cost: a Breakdown attached




3. Unanticipated or Unusually High O&M Costs During Review Period 8 N/ADescribe costs and reasons:Note: O&M costs have declined, because groundwater sampling was changed from quarterly to semi-annually.

V. ACCESS AND INSTITUTIONAL CONTROLS s Applicable

1. Fencing damaged B Location shown on site map s Gates secured a N/ARemarks: The fence was falling down along the northeast corner of the site, and the fence was on the ground along the

southwestern fenceline near monitoring well MW-8

B. Other Access Restrictions

1. Signs and other security measures a Location shown on site map o, N/ARemarks: Could not observe if all signs were present due to oevergrown vegetation and limited access around

northeastern and northwestern perimeters. Portions of the site were too overgrown with grass and shrubs to expectunauthorized access. Observed signs are noted on the site map.

TC_5YR_000928_A1T3A SiTElNSPECTIONCHECKLIST.WPD PAGE 4 OF 13 SITE INSPECTION AUGUST 9,2000


C. Institutional Controls

1. Implementation and enforcementSite conditions imply ICs not properly implemented: a Yes o No a, N/ASite conditions imply ICs not being fully enforced: sVes a No oN/AType of monitoring (e.g, self-reporting, drive by): State contractor visits the site twice a year.Frequency: Semi-annualResponsible party/agency: TNRCCContact:Name: Emmanuel NdameTitle: RPMDate: August 11,2000Phone Number: 512-239-2494Reporting is up-to-date: a Yes a No a, N/AReports are verified by the lead agency: .a Yes a No aN/ASpecific requirements in deed or decision documents have been met: a Yes s No a N/AViolations have been reported: BYes a No gN/AOther problems or suggestions: a Additional report attached (if additional space required).

2. Adequacy g ICs are adequate a ICs are inadequate aN/ARemarks: Unauthorized access to the site is currently not restricted because of damage to the perimeter fence.

D. General

1. Vandalism/trespassing g Location shown on site map a No vandalism evidentRemarks: Graffiti had been spray painted on the walls in several of the buildings.

2. Land use changes onsiteRemarks: The site is currently vacant.

i N/A

3. Land use changes offsiteRemarks: No land use changes were noted offsite.

BN/A

VI. GENERAL SITE CONDITIONS

A. Roads o Applicable aN/A

1. Roads damaged g Location shown on site map a Roads adequate gN/ARemarks:

B. Other Site Conditions

Remarks: Grass at the site needs to be mowed. Empty drums were present in two of the buildings.

TC_5YR_000928_ATT3A_SlTElNSPECTIONCHECKUST.WPD PAGE 5 OF 13 SITE INSPECTION AUGUST 9,2000


VII. LANDFILL COVERS g Applicable

A. Landfill Surface1. Settlement (Low spots)

Areal extent:Remarks:

o Location shown on site mapDepth:

n Settlement not evident

2. CracksLengths:Remarks:

g Location shown on site mapWidths: Depths:

g Cracking not evident

3. ErosionAreal extent:Remarks:

a Location shown on site mapDepth:

a Erosion not evident

4. HolesArea) extent:Remarks:


o Holes not evident

5. Vegetative Coverg Cover properly establishedRemarks:

g No signs of stress a Grass a Trees/Shrubs

6. Alternative Cover (armored rock, concrete, etc.)Remarks:

nN/A

7. BulgesAreal extent:Remarks:

o Location shown on site mapHeight:

a Bulges not evident

8. Wet Areas/Water Damageg Wet areaso Pondingg_Seepsg.Soft subgradeRemarks:

o Location shown on site map Areal extent:g Location shown on site map Areal extent:a Location shown on site map Areal extent:g Location shown on site map Areal extent:

g Wet areas/water damage not evident

9. Slope InstabilityAreal extent:Remarks:

g.Slides g Location shown on site map g No evidence of slope instability


TRIANGLE CHEMICAL COMPANY SITESECOND FIVE-YEAR REVIEW Srre INSPECTION CHECKLIST

B. Benches o. Applicable a N/A(Horizontally constructed mounds of earth placed across a steep landfill side slope to interrupt the slope in order to slowdown the velocity of surface runoff and intercept and convey the runoff to a lined channel.)

1 . Flows Bypass Bench a Location shown on site mapRemarks:

a N/A or okay

2. Bench BreachedRemarks:

o Location shown on site map a N/A or okay

3. Bench Overtopped o_ Location shown on site mapRemarks:

D N/A or okay

C. Letdown Channels a Applicable a N/A(Channel lined with erosion control mats, riprap, grout bags. or gabions that descend down the steep side slope of thecover and will allow the runoff water collected by the benches to move off of the landfill cover without creating erosiongullies.)

1. SettlementAreal extent:Remarks:

n Location shown on site mapDepth:

a No evidence of settlement

2. Material Degradation a. Location shown on site mapMaterial type: Areal extent:Remarks:

D, No evidence of degradation



n No evidence of erosion

4. UndercuttingAreal extent:Remarks:

a. Location shown on site mapDepth:

g_ No evidence of undercutting

5. ObstructionsType:Areal extent:Remarks:

Q Location shown on site map

Height:

nN/A



6. Excessive Vegetative Growthg Evidence of excessive growthg Location shown on site mapRemarks:

a No evidence of excessive growtha Vegetation in channels but does not obstruct flowAreal extent:

D. Cover Penetrations a Applicable oN/A

1. Gas Ventsg Active g PassiveD Properly secured/lockedg Evidence of leakage at penetrationRemarks:

DN/Ag Routinely sampledg Functioninga Needs 0& M

a Good condition

2. Gas Monitoring ProbesD Routinely sampledo Properly secured/locked g Functioningo Evidence of leakage at penetration g Needs O&MRemarks:

aN/A

D Good condition

3. Monitoring Wells (within surface area of landfill)g Routinely sampledg Properly secured/locked g Functioningg Evidence of leakage at penetration g Needs O&MRemarks:

aN/A

a Good condition

4. Leachate Extraction Wellsg Routinely sampledg Properly secured/locked g Functioningg Evidence of leakage at penetration g Needs O&MRemarks:

aN/A

a Good condition

5. Settlement Monuments g LocatedRemarks:

g Routinely surveyed aN/A

E. Gas Collection and Treatment g Applicable g N/A

1. Gas Treatment Facilitiesg Flaring g Thermal destructiong Good condition g Needs 0& MRemarks:

DN/AD Collection for reuse



2. Gas Collection Wells, Manifolds and Piping g N/Aa Good condition a Needs 0& MRemarks:

3. Gas Monitoring Facilities (e.g., gas monitoring of adjacent homes or buildings) o N/Aa Good condition a Needs 0& MRemarks:

P. Cover Drainage Layer o Applicable a N/A

1. Outlet Pipes Inspected o. Functioning a N/ARemarks:

2. Outlet Rock Inspected a Functioning gN/ARemarks:

G. Detention/Sedimentation Ponds a Applicable a N/A

1. Siltation a Siltation evident [3 N/AAreal extent: Depth:Remarks:

2. Erosion D Erosion evident gN/AAreal extent: Depth:Remarks:

3. Outlet Works o Functioning gN/ARemarks:

4. Dam a Functioning a N/ARemarks:

H. Retaining Walls a Applicable a N/A

1. Deformations a Location shown on site map a Deformation not evidentHorizontal displacement: Vertical displacement: Rotational displacement:Remarks:

2. Degradation g Location shown on site map a Degradation not evidentRemarks:



Perimeter Ditches/Off-s'rte discharge a Applicable o N/A

1. SiltationAreal extent:Remarks:


o Siltation not evident

2. Vegetative GrowthAreal extent:Remarks:

a Location shown on site mapType:

o Vegetation does not impede flow



a Erosion not evident

4. Discharge Structureg FunctioningRemarks:

g Location shown on site mapa Good Condition

a N/A

VIII. VERTICAL BARRIER WALLS g Applicable

1. SettlementAreal extent:Remarks:


a Settlement not evident

2. Performance Monitoringo Performance not monitoreda Performance monitoreda Evidence of breachingRemarks:

a N/A

Frequency:Head differential:

IX. GROUNDWATER/SURFACE WATER REMEDIES a Applicable

A. Groundwater Extraction Wells, Pumps, and Pipelines n Applicable 13 N/A

1. Pumps, Wellhead Plumbing, and Electricalg All required wells located a Good condition g Needs 0& MRemarks:

DN/A

2. Extraction System Pipelines, Valves, Valve Boxes, and Other Appurtenancesg System located g Good condition g Needs 0& MRemarks:

DN/A

PAGE100F13 SITE INSPECTION AUGUST 9,2000


3. Spare Parts and Equipmenta Readily availablea Requires UpgradeRemarks:

aN/Aa Good conditiona Needs to be provided

B. Surface Water Collection Structures, Pumps, and Pipelines D Applicable B N/A

1. Collection Structures, Pumps, and Electricalo Good condition a Needs 0& MRemarks:

aN/A

2. Surface Water Collection System Pipelines, Valves, Valve Boxes, and Other Appurtenances g N/Ag Good condition g Needs 0& MRemarks:

3. Spare Parts and Equipmenta Readily availablea. Requires UpgradeRemarks:

DN/Aa Good conditiona Needs to be provided

C. Treatment System a Applicable ja N/A

1. Treatment Train (Check components that apply)n Metals removal o Oil/water separationD Air stripping g Carbon adsorberso Additive (list type, e.g., chelation agent, flocculent)o Others (list):g Good condition n Needs O&MQ Sampling ports properly marked and functionala Sampling/maintenance log displayed and up to dateg. Equipment properly identifiedD Quantity of groundwater treated annually (list volume):a Quantity of surface water treated annually (list volume):Remarks:

a Bioremediationa Filters (list type):

2. Electrical Enclosures and Panels (properly rated and functional)o Good condition D Needs 0& MRemarks:

a N/A

3. Tanks, Vaults, Storage Vesselsa Good condition o Proper secondary containment g Needs O&MRemarks:

a N/A

TC_5YR_000928 ATT3A_SlTElNSPECTIONCHECKLIST.WPD PAGE 1 1 OF 13 SITE INSPECTION AUGUST 9,2000


4. Discharge Structure and AppurtenancesD Good condition n Needs 0& MRemarks:

ON/A

5. Treatment Building(s)D Good condition (esp. roof and doorways)g_ Chemicals and equipment properly storedRemarks:

aN/Ao Needs Repair

6. Monitoring Wells (pump and treatment remedy)a All required wells located o Properly secured/lockedD Good condition a Needs O&MRemarks:

ON/Aa Functioning o Routinely sampled

D. Monitored Natural Attenuation a Applicable aN/A

1. Monitoring Wells (natural attenuation remedy) nN/As All required wells located s Properly secured/locked a Functioning a. Routinely sampleds Good condition s Needs 0& M (as noted)Remarks: MW-3 has damaged lid and is not locked. MW-8 was not locked. MW-9 and MW-10 are flush mount wells

that do not have locks. MW-11 could only be observed from a 5-8 ft. distance (a locked gate and tall grass and shrubsprevented access). MW-5 and MW-6 had damaged guard posts.

X. OTHER REMEDIES H Applicable

PAGE120F13 SITE INSPECTION AUGUST 9,2000


XI. OVERALL OBSERVATIONS

A. Implementation of the Remedy

Describe issues and observations relating to whether the remedy is effective and functioning as designed. Begin with abrief statement of what the remedy is to accomplish (i.e., to contain contaminant plume, minimize infiltration and gasemission, etc.)

The only remaining contamination at the site is in the groundwater. The contaminant plume does not appear to be migrating,although perimeter clean wells should be sampled more frequently to ensure continued lack of migration. Contaminantconcentrations, except for benzene at MW-6, appear to be attenuating. The fence is supposed to restrict access to the site,but is currently damaged.

B. Adequacy of O&M

Describe issues and observations related to the implementation and scope of O&M procedures. In particular, discusstheir relationship to the current and long-term protectiveness of the remedy.

Several wells need maintenance, and currently access to the site is not restricted due to damage to the perimeter fence. Aslong as attenuation continues to occur, monitoring would remain the only necessary action at the site. The wells should berepaired. The fence should also be repaired to prevent further vandalism/unauthorized access to the site and/or monitor wellnetwork.

C. Early Indicators of Potential Remedy Failure

Describe issues and observations such as unexpected changes in the cost or scope of O&M or a high frequency ofunscheduled repairs, that suggest that the protectiveness of the remedy may be compromised in the future.

The remedy appears to continue to be protective as planned.

D. Opportunities for Optimization

Describe possible opportunities for optimization in monitoring tasks or the operation of the remedy.

Groundwater sampling has been reduced from quarterly to semi-annually; this change is appropriate. Future monitoring maysuggest a change to annual sampling is appropriate.

TC_5YR_000928_ATT3A_SlTElNSPECTIONCHECKLIST.WPD PAGE 13 OF 13 SITE INSPECTION AUGUST 9,2000

Inspection Team RosterTriangle Chemical Company, 5 Year ReviewAugust 9,2000

Name

Margaret O'Hare

Darren Davis

Agency

CH2M HILL

CH2M HILL

Phone Number

(972)980-2170

(972)980-2170

PAGE 1 OF 1 SEPTEMBER 2000



TC 5YR 000928.WPD SEPTEMBER 2000



TC_5YR 000928.WPD SEPTEMBER 2000


Attachment 4

Site Inspection Photographs




TC 5YR_000928.WPD SEPTEMBER 2000

Second Five-Year Review Site Inspection PhotographsTriangle Chemical Company Site

Photograph 1.

Facing west from outside east comer offacility, along State Highway 87. Notedamage to fence.

The arrow is pointing to the former officebuilding (refer to Figure 1 Site Map).

PHOTOGRAPHS TAKEN AUGUST 9, 2000 PAGE1 OF 27


Photograph 2.

Facing north toward same section ofdamaged fence as seen in Photograph 1,different view. The buildings in thebackground are on the facility to thenortheast of the site.

Note restricted entry sign (white, on fence,left of damaged section)

TC 5YR 000928_ATT4 PHOTOGRAPHS.WPD PHOTOGRAPHS TAKEN AUGUST 9,2000 PAGE 2 OF 27


Photograph 3.

Facing north from outside south comer offacility, along SH 87. Same buildings inbackground as those seen in Photograph 2.

Access gate is open for our entry; the gatewas locked upon our arrival.

Note restricted entry sign, white, on fenceto the right of the open gate.

PHOTOGRAPHS TAKEN AUGUST 9, 2000 PAGE 3 OF 27

Second Five-Year Review Site Inspection Photographs_________Triangle Chemical Company Site

Photograph 4.

Facing north, from outside southern comerof perimeter fence, along SH 87. Openaccess gate visible at right side of photo;note damaged fence just left of center (atarrow).

TC_5YR_000928_ATT4_PHOTOGRAPHS.WPD PHOTOGRAPHS TAKEN AUGUST 9, 2000 PAGE 4 OF 27


Photograph 5.

Facing northwest from outside perimeterfence at restricted entry sign on fence toright of access gate. Former office buildingis in background.



Photograph 6.

Facing northwest from inside perimeterfence toward former office building.

TC_5YR 000928 An4 PHOTOGRAPHS.WPD PHOTOGRAPHS TAKEN AUGUST 9,2000 PAGE 6 OF 27


Photograph 7.

Facing north toward Monitor Well 1.

PHOTOGRAPHS TAKEN AUGUST 9,2000 PAGE 7 OF 27


Photograph 8.

Facing south-southeast, toward MonitorWell 1.



Photograph 9.

Facing north-northwest from vicinity ofMW-1. Note height of vegetation. ProcessBuilding No.3 is visible in rightbackground.



Photograph 10.

Facing northeast toward MW-5. Southwestwall of Process Building No. 3 inbackground.

PHOTOGRAPHS TAKEN AUGUST 9,2000 PAGE 1 0 OF 27


Photograph 11.

Side view of MW-5, facing north. Notebent guard posts and height of vegetation.

TC 5YR 000928 An4 PHOTOGRAPHS.WPD PHOTOGRAPHS TAKEN AUGUST 9, 2000 PABE 1 1 OF 27


Photograph 12.

Facing northeast toward MW-4 (flush-mount). Process Building No. 3visible in background.

TC_5YR_000928 ATT4 PHOTOGRAPHS.WPD PHOTOGRAPHS TAKEN AUGUST 9,2000 PAGE 12 OF 27


Photograph 13.

Facing northwest toward MW-7 (left) andMW-6.



Photograph 14.

Closer view of MW-6.


Second Five-Year Review Site Inspection Photographs__________Triangle Chemical Company Site

Photograph 15.

MW-9 (flush mount well) in north comer offormer Process Building No. 1.

Note used bailer left on floor (smallerarrow).

TC_5YR_000928_ATT4_PHOTOGRAPHS.WPD PHOTOGRAPHS TAKEN AUGUST 9,2000 PAGE 15 OF 27


Photograph 16.

Vandalism evident in aisle between formerProcess Building No. 1 and former ProcessBuilding No. 2 (facing east from area ofMW-9).



Photograph 17.

Facing north toward inside comer of formerProcess Building No. 2. Access to MW-3is through bent siding at left side of photo.

Note evidence of vandalism.



Photograph 18.

Facing northwest through bent siding inwall of former Process Building No. 2;MW-3 visible outside (arrow).

TC_5YR_000928_ATT4 PHOTOGRAPHS.WPD PHOTOGRAPHS TAKEN AUGUST 9,2000 PAGE 18 OF 27


Photograph 19.

Closer view of MW-3. Note perimeterfence in background.

TC 5YR 000928 An4 PHOTOGRAPHS.WPD PHOTOGRAPHS TAKEN AUGUST 9,2000 PAGE 19 OF 27


Photograph 20.

Closeup of MW-3; no well cap present.



Photograph 21.

Facing northeast at north comer ofperimeter fence. Former Process BuildingNo. 2 visible at right.

TC 5YR 000928 ATT4 PHOTOGRAPHS.WPD PHOTOGRAPHS TAKEN AUGUST 9,2000 PAGE 21 OF 27


Photograph 22.

Facing southwest from same position as Photo 21. Note perimeter fencebehind extensive vegetation.



Photograph 23.

Facing north, inside southeast end offormer Process Building No. 2, towardaccess to MW-11 (opening in wall withgate; center of photo).

Note empty drums staged near gate and atleft.



Photograph 24.

Facing north toward MW-11 throughlocked access gate. Well is located onneighboring property.

TC_5YR_000928_ATT4_PHOTOGRAPHS.WPO PHOTOGRAPHS TAKEN AUGUST 9, 2000 PAGE 24 OF 27


Photograph 25.

Facing northwest along side of formerOffice Building. Note perimeter fence atleft; note damage at larger arrow.

MW-8 visible at smaller arrow.

TC 5YR 000928_ATT4_PHOTOORAPHS.WPD PHOTOGRAPHS TAKEN AUGUST 9, 2000 PAGE 25 OF 27


Photograph 26.

Facing northwest toward MW-8.

Note damaged perimeter fence at left(arrow). Fence is completely down at thispoint.



Photograph 27.

Facing south toward damaged perimeterfence (different view than Photograph 26).Note fence is completely down at right ofphoto, and damaged in center.

Building at right in background is onneighboring property.
