CONROE

CREOSOTING

(MONTGOMERY

COUNTY)

CONROE,

TEXAS

EPA REGION 6

U.S. CONGRESSIONAL DISTRICT 08

Contact: Gary Baumgarten
214-665-6749

Updated: May 2015

EPA ID# TXD008091951
Site ID: 0601732

Current Status

Ari independent review team is conducting an optimization review of the selected remedial action for the
site. Recommendations from the optimization review are based on an evaluation and analysis of existing
site information, represent the technical views of the optimization review team and are intended to help
the site team identify opportunities for improvements in the current site remediation strategy. EPA and the
Texas Commission on Environmental Quality (TCEQ) are reviewing the draft optimization report.

EPA continues to implement the long-term ground water monitoring program which began in November
2005. Results from the ground water monitoring program are used to assess the natural attenuation of
pentachlorophenol in the shallow aquifer. A landfill constructed at the Site is securely fenced, has locked
gates, and is marked with signs. TCEQ completed repairs to the landfill cover over the RCRA vault
containing the contaminated soils and sediments from the site.

EPA completed the Second Five-Year Review for the Site on September 27, 2013. The Second Five-
Year Review determined that the remedy for on-site soils and off-site sediment is protective of human

health and the environment because the waste has been removed and contained. The remedy for ground
water is protective of human health and the environment in the short term because there is no evidence
that there is current exposure, and the remedy is being implemented as planned to reduce the volume of
contamination and to control migration.

Conroe Creosoting

1

EPA Publication Date: June 9, 2015


-------
Background

The Conroe Site is a former wood-treating facility located at 1776 E. Davis Street, Conroe, Montgomery
County, Texas, The former wood-treating facility occupies approximately 147 acres and operated from
1946 until March 1997. The Site is fenced and
borders residential property to the east, State
Highway 105 to the south, and forested land to the
west and north. The facility consisted of two process
areas, one tank area, two kilns, a re-work area, a
vehicle maintenance shop, boiler, lumber shed, a
pole machine, two fuel pumps, an office, a sales
office, and a retail office along with several storage
sheds and storage areas prior to a removal action
conducted by the .

Three wood preserving processes were used at the
facility, including pentachlorophenol (PCP), creosote,
and copper chromated arsenate (CCA). The PCP
and creosote wood preserving processes used
pressure to force a solution of PCP or creosote dissolved in diesel into the wood. The CCA treatment
process is water based and occurs at ambient pressures. The treated wood was then allowed to dry on a
drip pad. Treatment residues from these processes were scraped from the drying pad for shipment off-
site. The facility was closed down by the Montgomery County Tax Assessor/Collector in March 1997, due
to delinquent taxes.

In September 2002, the EPA started a time-critical removal action of on-site structures and soils. All the
contaminated material, soils, sediments, and solidified wastes were placed inside an on-site Resource
Conservation Recovery Act (RCRA) vault. A total of 252,000 cubic yards of contaminated material was
placed inside the vault.

The Record of Decision (ROD), signed on September 29, 2003, set forth the selected remedy for the site,
which includes monitored natural attenuation of the contaminants in the ground water, no further action
for the on-site soils and offsite sediments, iong-term maintenance of the RCRA vault, and placement of
institutional controls.

Benefits

The removal action addressed contamination above health-based levels at on-site and off-site locations,
including Stewart's Creek and off-site drainage areas. The ground water investigation determined that
contamination from the facility has only impacted the ground water beneath the facility and is not a threat
to the surrounding private water supply wells. The long-term monitoring program will continue to monitor
the contaminant levels in ground water.

National Priorities Listing (NPL) History

NPL Inclusion Proposal Date:	April 30, 2003

NPL Inclusion Final Date:	September 22, 2003

Conroe Creosoting

2

EPA Publication Date: June?, 2015


-------
Location:

The Site is located in Conroe, Montgomery County, approximately 30 miles north of
Houston, Texas.

Population: Aproximately 15,000 people live within two miles of the site.

Setting:	The site consists of 147 acres and is a former wood treating facility. There is a residential

community to the east, a wooded area to the north, and commercial activities to the west
and south. The shallow water-bearing zone is 60 feet deep and is currently not being
used. The first water-bearing zone used for domestic supply is 125 feet deep. The City of
Conroe water supply is 400 to 1000 feet below the surface.

Site Map

The following map illustrates the site location on the east side of Conroe, Texas.

Legend:

®	Sand-1 Shallow Monitoring Well

^	Sand-1 Cluster Monitonng Wfell

®	Sand-2 Monitoring Well

®	On-site Water well

V7A Business Park

Residential Area
j	) Approximate Boundary

Conroe Creosoting

3

EPA Publication Date: June?, 2015


-------
Conroe Creosoting	4	EPA Publication Date: June 9,2015


-------
The following site map illustrates the PCP concentration levels in ground water based on the January
2013 ground water sampling data.

PCP concentrations shown in red are above the PCP cleanup goal of 1 ppb (or 1 M9/L).

Conroe Creosoting Company
Superflind Site

Conroe, Montgomery County, Texas

PCP Concentrations
Sand-1 Shallow Monitoring Wells

January 2013

gend:

>	Sand-1 Shallow M onitoring Well
5 Sand-1 Cluster Monitoring Well

>	Sand-2 Monitoring Well

>	Onsite Water Well
2I Business Park

Residential Area
Approximate Boundary

less than MCLfor PCP of 1pg/L

eater than or equal to MCLfor PCP of Ipg'l-

US EPA Maximum Contaminant Level

Tetrachlorophenol

Micrograms per liter

indicates duplicate sample result

Not detected at quantitation limit

Wastes and Volumes

Approximately 252,000 cubic yards of soils exceeded the EPA Region 6 Human Health Medium-Specific
Screening Levels for either arsenic, chromium, PCP, total creosote compounds, or dioxin and furans and
were placed in the site RCRA vault during the emergency response action. The cleanup goal for PCP in
the ground water is 1 part per billion (ppb).

Health Considerations

The Second Five-Year Review determined that the remedy for the Site is protective of human health and
the environment, and will remain so provided the follow action items are addressed:

Establish a grass cover on the cap of the RCRA vault;

Monitor and characterize leachate accumulation in the RCRA vault on a regular basis;

Install temporary bollards around flush mounted wells and ensure that monitoring wells are
locked;

Continue monitoring ground water using the exiting monitoring well network;

Evaluate existing data to determine if additional ground water characterization of the Shallow

Sand-1 aquifer is necessary.

Conroe Creosoting

5

EPA Publication Date: June?, 2015


-------
Record of Decision (ROD)

A Final Record of Decision was signed on September 29, 2003.

Community Involvement

Proposed Plan:
Public Meeting:

Issued July 18, 2003
July 31, 2003

Information Repository:

Montgomery County Memorial Library
104 I-45 North
Conroe, TX 77301
(936) 442-7712

Site Contacts	

EPA Remedial Project Manager:
EPA Regional Public Liaison:

TCEQ Project Manager

EPA Superfund Region 6 Toll Free Number:

Gary Baumgarten	214-665-6749

Donn Walters	214-665-6483

SubhashPal	512-239-4513

1-800-533-3508

Conroe Creosoting

6

EPA Publication Date: June 9, 2015


-------