PUBLIC HEALTH ASSESSMENT ADDENDUM
TEXAS CITY, GALVESTON COUNTY, TEXAS
The MOTCO National Priorities List (NPL) site is located in theCity of LaMarque, Galveston County, Texas. The contaminants ofconcern consist of several volatile organic compounds (VOCs) andsemi-volatile organic compounds (semi-VOCs). Evidence of heavymetal contamination was also noted. Areas of highest contaminantconcentration are in the subsurface soil, on-site pits, andshallow ground water. Population exposure to this site islimited due to location; those most likely to be exposed areunprotected remedial workers and trespassers. Although thesegroups might be exposed by skin contact with, ingestion of, orinhalation of contaminated soil and pit waste, there is noevidence that exposures to site contaminants are occurring. Therefore, the site is currently classified as no public healthhazard. The site could pose a future a public health hazard ifnot remediated, current site conditions change, or remediationworkers fail to follow personal protection guidelines. TheAgency for Toxic Substances and Disease Registry (ATSDR)recommends that institutional controls be implemented to preventthe installation of wells that draw water from the contaminatedshallow aquifers. ATSDR also recommends that additional surfacewater and biota samples be taken in the Del Industries' pond. The Environmental Protection Agency (EPA) has installed anincinerator for on-site disposal of waste. A continuousperimeter air monitoring system has also been installed to insurethat nearby residents are not exposed to site-relatedcontaminants. No air sample results, however, were available toevaluate during the preparation of this Addendum.
The ATSDR Health Activities Recommendation Panel (HARP) and theTexas Department of Health (TDH) have evaluated the MOTCO sitefor appropriate follow-up with respect to health activities. Because there is no indication that human exposure to sitecontaminants at levels of public health concern is occurring orhas occurred, this site is not being considered for follow-uphealth activities at this time. However, if emissions from theincineration process or other environmental data become availablesuggesting that human exposure to significant levels of hazardoussubstances is currently occurring or has occurred in the past,ATSDR and TDH will reevaluate this site for any indicatedfollow-up. In addition, TDH recommends community education toresidents concerning the emissions from the incinerator pilottest.
To respond to community concerns and based on the HARPrecommendations, the following actions have been or will beperformed to meet the needs expressed by the Recommendations ofthis Health Assessment Addendum.
TDH in cooperation with the ATSDR will conduct the followingpublic health actions:
- As air emission data from the site and incinerationprocess become available, ATSDR and TDH will evaluate this datawith regards to public health impact. This data will also beshared by TDH with the Texas Air Control Board for theirevaluation.
- TDH in conjunction with ATSDR will provide communityeducation to residents concerning emissions from the incinerator.
- ATSDR and TDH will continue to coordinate efforts withfederal and state environmental agencies in evaluating the site'simpact on public health and will provide recommendations toaddress public health issues.
The MOTCO site is an NPL site located in the City of La Marque,Galveston County, Texas. The site covers 11.3 acres and islocated near the junction of Interstate 45 and Texas Highway 3. It is bounded on the east by Texas Highway 3, on the northwest byan abandoned trailer park, and on the southwest by theright-of-way for the Houston Lighting and Power (HP&L) Companytransmission lines. The site is fenced and has locked andmonitored entrances.
The MOTCO National Priorities List (NPL) site was placed on theNPL in 1982. The Centers for Disease Control (CDC) completed aHealth Assessment, based on the existing data, for the site in1984 (Appendix A). Additional environmental information for thesite has been generated since the completion of the initialhealth assessment. In cooperation with ATSDR, the EnvironmentalEpidemiology Program of the Texas Department of Health evaluatedthe new information and completed an addendum to the originalhealth assessment. Data on the environmental and public healthissues addressed in this report were obtained from theEndangerment Assessment (EA) and the Supplemental FeasibilityStudy Investigation (SFSI). (1,2)
Historical operations at the site include a facility in the late1950's to recycle styrene tars generated by local industries anda petroleum salvage operation in 1961-1968.
MOTCO, Inc. purchased the site in 1974. Site operations involvedthe reclamation of creosote extenders, fuel, and solvent wastesat the site. In 1976, the Texas Department of Water Resourcesissued an enforcement order requiring MOTCO to secure the siteand submit closure plans. MOTCO subsequently filed forbankruptcy and eventually abandoned the facility.
In 1980, the United States Coast Guard extended and raised theperimeter dikes, removed storage drums, and erected a six-footfence around the site. In September 1981, March 1983, andSeptember 1983, EPA conducted three emergency response actionsfor the treatment and discharge of pit surface waters. In 1985and 1986, EPA removed storage tanks from the site disposing ofthem in an off-site certified landfill.
To expedite on-site waste-pit remediation, EPA chose, in 1983, todivide the remediation process into two components or operableunits: the Source Control Operable Unit (SCOU) and the Managementof Migration Unit (MOM).
The SCOU addresses actions taken within the fenced siteboundaries to remediate surface contamination in the surface pondarea (to one foot below the sludge-soil interface), tank farmarea, and the adjacent perimeter area. The SCOU includes plansfor the excavation of the eight on-site waste pits containingcontaminated water and organic waste liquids. In March 1985, EPAchose incineration as the preferred remedial alternative for theSource Control Operable Unit.
Construction of an on-site incinerator and waste materialhandling facility began in early 1989. As part of theconstruction process for the material handling facility, thewaste from Pit 1 was removed and the area enclosed. The testburn of the first incinerator was completed in October 1990 withthe second test burn completed in July 1991.
The MOM unit is concerned with existing and potential off-sitemigration of chemicals from the MOTCO site following completionof SCOU clean-up work. Remediation plans will address off-sitetop soil and on- and off-site subsurface soil and ground water. The Record of Decision (ROD) for the MOM unit was signed inSeptember 1989 and remediation will include pumping and treatingthe ground water, as well as excavation, consolidation andcapping of the contaminated soils on site.
A Health Assessment for the MOTCO site was completed by theCenters for Disease Control (CDC) and released on July 20, 1984. The Assessment, based on data available at the time, concludedthat the site constitutes a significant potential public healththreat. Furthermore, CDC advised that remediation should takeplace to reduce or eliminate the potential for exposure.
On May 16, 1990, Jean Brender, Judy Henry, and Michelle Kellyfrom the Texas Department of Health (TDH) in addition torepresentatives from EPA Region 6 and Galveston County HealthDepartment (GCHD) met with officials from the MOTCO Trust Groupand Metcalf and Eddy. A walking tour of the on-site area wasconducted along with a visual survey of Omega Bay and BayouVista.
During physical inspection of the site it was noted that theentire site was fenced with locked and monitored entrances. Onthe day of the site visit, the two borrow pits located southwestof the site contained water. A borrow pit is a excavated areawhere material has been dug for use as fill in another location. It was also noted that the "Dispose-All" Company, east-southeastof the site and across State Highway 3 had been renamed "DelIndustries". The primary physical hazard associated with on-site areas were the waste pits. At the time of the site visit, these were not fenced and little barrier existed between workers and entrance to the pits.
The MOTCO site is located approximately two miles southeast ofthe City of LaMarque, Galveston County, near the southeast coastof Texas. (See Appendix B for site location map.) The mainindustries in the area are oil and gas refining, petrochemicalprocessing, and various types of manufacturing. The nearbyeconomy is heavily influenced by ship channel activities. Theestimated 1987 population of Galveston County is 209,274 persons,with the City of LaMarque accounting for 16,162 persons.
Situated on the Gulf coastal plain, at the edge of a coastalmarsh system, the MOTCO site exists approximately two miles fromGalveston Bay and 1.5 miles from the Jones Bay/Trinity-SanJacinto estuary. The facility is on an 11.3 acre tract of land. The elevation of the site is approximately 5 feet above mean sealevel (MSL), placing it within the 100-year tidal flood plain. Two independent businesses, Central Freight Lines (truckterminal) and Del Industries, are located approximately 500 feetsoutheast of the site.
Two residential subdivisions, Omega Bay and Bayou Vista(population of 1,163), are located approximately 1500 feetwest-southwest and 2000 feet south-southwest of MOTCO,respectively. The two subdivisions are physically separated fromthe MOTCO site by the Gulf Freeway. The nearest privateresidence not separated from the site by the freeway isapproximately 2000 feet to the northwest of the site.
The area surrounding the MOTCO site is used primarily forindustrial purposes. The nearby bay and estuary waters are usedfor commercial and sport fishing, recreation, and transportation.
The GCHD officials were contacted about the availability of anyhealth outcome data of residents living in the area of the MOTCOsite. They reported no specific health outcome data for theseresidents.
Routinely collected live birth, death and fetal death certificatedata are available both in the local and state healthdepartments. These data bases are not accessible for cities lessthan 2500 people or for census tract. Therefore, vitalstatistics are not available for the Omega Bay and Bayou Vistasubdivisions.
The TDH Cancer Registry Division collects incidence data forcancer in Texas through mandatory hospital reporting of cases. Incidence data are incomplete for TDH Region 4 in which the MOTCOsite is located. Therefore, this data base was not used becausethe calculated incidence rates would underestimate the trueincidence rates.
To adequately determine community health concerns relating to theMOTCO site, the Galveston County Health District Board receivedcomments from area residents at a meeting held on May 30, 1990. The TDH Environmental Epidemiology staff made additionalinquiries to the Texas Water Commission, Agency for ToxicSubstances and Disease Registry (ATSDR), and the University ofTexas Medical School at Galveston, to determine any communityhealth concerns. Issues surrounding on-site incinerationcomprise the majority of community concerns. Citizens wereconcerned with regulatory aspects of the incinerator, along withpossible exposure to heavy metal contamination from incineratoremissions.
A local citizen's group (unnamed) proposed a health study whichwas to focus on biological monitoring (blood and urine) formetals in nearby residents and on-site workers, before, during,and after incineration of wastes takes place. The citizen'sgroup approached both ATSDR and GCHD with the proposal. Uponreview by ATSDR staff, the study could not be conducted becausethe proposal did not meet ATSDR's criteria for a health study. It was suggested that the citizen's group pursue other sources tofund the health study. TDH staff encouraged members of the groupto maintain contact with TDH during site remediation.