Historic treatment of rail ties in the Houston, Texas Fifth Ward and Kashmere Gardens neighborhoods has exposed residents to cancer-causing soil contamination. Creosote and its extenders were used in wood preservation processes at a nearby rail yard and have been identified as carcinogens that are hazardous to human health.
Former Houston Mayor Sylvester Turner and the EPA have advocated alongside the community for environmental justice. As of 2019, the Greater Fifth Ward neighborhood had a majority population of color: 43% non-Hispanic Black, 51% Hispanic or Latinx, and 4% non-Hispanic white. As of 2019, the Kashmere Gardens neighborhood had 9,930 residents, 59% of which were non-Hispanic Black, 36% were Hispanic or Latinx, and 3% were non-Hispanic white.
For decades, the defunct Southern Pacific Railroad wood-preserving facility dumped chemicals into an unlined pit for disposal, and the facility's operations were eventually linked to groundwater contamination observed at the site. Residents noticed high cancer rates in the community, and the Texas Department of State Health Services confirmed a cancer cluster in the area in 2019. Later, in 2021, an assessment by the same organization discovered that there were higher than expected amounts of acute lymphoblastic leukemia in a roughly 2-mile area surrounding the rail yard. In the same year, the EPA collaborated with the Houston Health Department and Mayor Turner to begin addressing these concerns. In 2022, the City of Houston, Harris County, and the nonprofit organization Bayou City Initiative filed a lawsuit against Union Pacific Railroad under the Resource Conservation and Recovery Act about the contamination and initiated a plan to support residents. An agreement was later reached on February 27th, 2023, between the Environmental Protection Agency and the Union Pacific Railroad company that required the Union Pacific Railroad company to perform various types of soil and vapor intrusion testing for the sake of identifying any contaminants that may be present. As of 2023, the Fifth Ward Voluntary Relocation Plan has begun with an initial $5 million from the City of Houston allocated to the community. In 2024, results from further soil testing will be released.
Sources of contamination
Creosote Creosote has been used as a wood preservative since the 1800s. Distilled from coal tar and composed of more than 200 aromatic hydrocarbons, creosote was applied to outdoor wood products such as railway ties and utility poles to prevent rotting or consumption by termites and pests. In 1988, the U.S. Environmental Protection Agency's Integrated Risk Information System released a chemical assessment report on creosote, classifying it as a carcinogen.
At the Fifth Ward railyard site, creosote waste materials were able to leach out of unprotected disposal pits and into the surrounding soil. Over time, a plume of concentrated liquid contaminants from the pits descended until it reached an impermeable soil layer and began to spread horizontally, pushing the creosote plume underneath the neighborhoods surrounding the railyard. Today, more than 110 homes in the Kashmere Gardens neighborhood sit above the plume.
Polycyclic Aromatic Hydrocarbons Polycyclic aromatic hydrocarbons, also known as PAHs, are an umbrella term for a class of over 100 chemicals that are frequently present as a result of the partial burning of gas, wood, coal, or waste material. Additionally, they commonly appear in wood preservation sites such as the 5th Ward. These chemicals travel through water and adhere to soil particles, allowing them to seep into groundwater, lengthening the amount of time it takes for them to break down, which can be anywhere from months to years. PAHs located in groundwater have high chances of leaking into and contaminating drinking water, especially if the water is coming from a private well. PAHs also have capabilities, such as being hydrophobic, that allow them to spread through soil, air, water, and vegetation. The Environmental Protection Agency has designated 16 priority PAHs, 7 of which are expected carcinogens.
Benzo[a]pyrene, one of the seven carcinogens and a prominent PAH found in the 5th Ward, has been understood to have lasting effects on reproductive organs and developing fetuses. It has also been shown to cause liver, skin, lung, kidney, throat, stomach, and bladder cancer in animals, along with lung and skin cancer in humans.
Dioxin To increase the volume of creosote available for wood treatment, Southern Pacific used creosote extenders in the site's treatment process. Concerns arose when it was revealed that some of these extenders were sourced from what are now Houston-area Superfund sites––including Brio Refining, Dixie Oil Processors, and Motco––bringing the extender's safety and toxicity into question. Known carcinogens, such as polychlorinated biphenyls, vinyl chloride, mercury, and lead, have all been found at these Superfund sites during historical tests.
In 2022, soil samples taken from the Kashmere Gardens neighborhood tested positive for the chemical dioxin, a persistent organic pollutant that poses a threat to human health through bioaccumulation. In prior studies of environmental contaminants (e.g. Agent Orange), dioxin exposure has been linked to cancers such as soft tissue sarcoma, Hodgkin's and non-Hodgkin's lymphoma, lung, and prostate cancers. Low-temperature combustion of organic and inorganic chlorides, such as polyvinyl chloride (PVC), has been shown to form dioxin; the dioxin found at the rail yard was likely created when the mixture of creosote and creosote extender was incinerated for disposal. Dioxin exposure has also been linked to liver cancers, one of the prevalent types of cancer in the Fifth Ward cancer cluster.
History
Houston Wood Preserving Works operational period (1899-1984) The exact onset of chemical wood treatment at the Houston Wood Preserving Works is unclear. The Union Pacific Railroad company says that Southern Pacific Transportation Company began chemical wood treatment in 1899 at the Houston Wood Preserving Works site. However, according to the City of Houston 90-Day Notice of Intent to Sue, it was not until 1911 that Southern Pacific Railroad Company established the Houston Wood Preserving Works at 4910 Liberty Road to treat railroad ties with creosote. The facility also used creosote extenders––other preservatives now considered hazardous––which Southern Pacific purchased from up to three Houston area suppliers whose sites are now EPA Superfund sites: Brio Refining and Dixie Oil Processors, in the Friendswood area, and Motco, in La Marque.
From its inception until operations ended in 1984, the Wood Preserving Works used open, unlined pits for disposal of creosote by-products. The tar-like substance seeped down to form a “creosote plume” under the Wood Preserving Works site and neighboring areas. The surrounding area had several industrial facilities, many of which contributed to pollution in the area; today, it is considered a “brownfield” area. As a result, it is difficult to ascertain all possible sources of contamination of nearby soil and water.
According to the Notice of Intent to Sue, creosote contamination from the Wood Preserving Works reached the groundwater under the Kashmere Gardens neighborhood sometime in the 1970s. In 1974, an explosion on Southern Pacific's site released vapors, damaged buildings, and injured many people. Similarly, in 1979, chemical-laden wastewater from the wood treatment caught fire in a ditch at the Wood Preserving Works. Much more recently, in 2014, Union Pacific paid residents in the area who agreed to use city water instead of groundwater on their properties, which may have been contaminated as far back as the 1970s.
In 1984, the EPA significantly restricted the use of creosote as a wood preservative and proposed to ban the use of creosote for any purpose other than wood preservation due to its status as a likely carcinogen. The same year, Southern Pacific ceased creosoting operations at the Wood Preserving Works. Shortly thereafter, Southern Pacific began cleanup operations of the site and dismantled all buildings. The area is still a rail yard, mostly paved over. Today, “tar-like sludge,” believed but not confirmed to be by-products from the creosote works, still seeps up between cracks in the pavement.
Union Pacific acquisition and clean-up attempts In 1997, Union Pacific Railroad Company merged with Southern Pacific Railroad Company in a $5.4 billion deal, forming one of the largest railroad networks in the United States. Union Pacific management acquired the Southern Pacific Railroad Company and assumed responsibility for the Fifth Ward rail yard site. Union Pacific acknowledged Southern Pacific's use of an extender in the creosote treatment process, but it announced its use was discontinued upon discovering that the materials came from the three Superfund sites. Union Pacific took over environmental remediation at the site after the acquisition
Union Pacific extracted samples of creosote from wells on the site and found a large creosote plume that sat under the nearby neighborhoods. Prior cleanup efforts involved drilling 40-foot deep wells throughout the site to remove creosote and contaminated soil, and installing barriers with soil and asphalt caps consisting of clay, concrete, and other materials to prevent contamination from spreading. Union Pacific also claimed to periodically test the toxicity of the groundwater, monitor the chemical plume, and extract the creosote through wells. In 2014, Union Pacific proposed a plan for remediation to the Texas Commission on Environmental Quality (TCEQ) as part of its application for a Hazardous Industrial Waste Permit renewal. They also requested several amendments to the permit, including the establishment of an environmental management zone that would use “monitored natural attenuation” for the contamination, intending to allow the creosote to degrade and evaporate without direct intervention. Additionally, they notified residents of the creosote pollution, as required by the state environmental permits. The TCEQ responded, finding this plan to be inadequate, and advised increased testing, monitoring, and extraction efforts. As of April 2024, the plan is still in discussion, as Union Pacific maintains that the creosote plume does not pose a health risk
Initial reports of pollution The identification of cancer clusters in the Fifth Ward was publicly announced in 2019. By this time, however, creosote and creosote extenders had already been present in the Fifth Ward as a result of the chemical dumping from years prior. The railroad yard's industrial waste came from the Brio Refining Superfund site, which was allegedly responsible for the reprocessing of chemicals. In 1991, the Houston Chronicle reported that 8 of 19 babies born within blocks of the dumping site were born with birth defects. Furthermore, 667 homes and an elementary school were shut down in Southbend, the adjacent neighborhood, as a result of growing health concerns.
The reprocessing of chemicals at the Brio Refining Superfund site was, according to chemical engineer Jim Tarr, “absolutely without a doubt dangerous.” In 2002, he wrote a report to provide information for a law firm representing workers who were allegedly harmed on the site. In his report, he claimed that Union Pacific mixed creosote with hazardous industrial waste to increase its available volume, using the waste as an “extender,” and that the toxicity associated with the creosote extender is more concerning than creosote itself.
Identification of cancer cluster