| (22) Deed notice--An instrument filed in the real property records of the county where the affected property is located that is intended to provide to owners, prospective buyers and others notice and information regarding, but which does not, by itself, restrict use of the affected property. (23) De minimus --The description of an area of affected property comprised of one acre or less where the ecological risk is considered to be insignificant because of the small extent of contamination, the absence of protected species, the availability of similar unimpacted habitat nearby, and the lack of adjacent sensitive environmental areas. (24) Ecological benchmark--A state standard, federal guideline, or other exposure level for a chemical of concern in water, sediment, or soil that represents a protective threshold from adverse ecological effects. An ecological benchmark may also be a toxicity reference value that is established by the person based on scientific studies in the literature. (25) Ecological hazard index--The sum of individual ecological hazard quotients of COCs within a class of compounds that exert ecological effects which have the same toxicological mechanism or endpoint (e.g., PAHs, PCBs). (26) Ecological hazard quotient--The ratio of an exposure level to a chemical of concern to a toxicity value selected for the risk assessment for that chemical of concern (e.g., a no observed adverse effects level). (27) Ecological protective concentration level--The concentration of a chemical of concern at the point of exposure within an exposure medium (e.g., soil, sediment, groundwater, or surface water) which is determined in accordance with §350.77(c) or (d) of this title (relating to Ecological Risk Assessment and Development of Ecological Protective Concentration Levels) to be protective for ecological receptors. These concentration levels are primarily intended to be protective for more mobile or wide-ranging ecological receptors and, where appropriate, benthic invertebrate communities within the waters in the state. These concentration levels are not intended to be directly protective of receptors with limited mobility or range (e.g., plants, soil invertebrates, and small rodents), particularly those residing within active areas of a facility, unless these receptors are threatened/endangered species or unless impacts to these receptors result in disruption of the ecosystem or other unacceptable consequences for the more mobile or wide-ranging receptors (e.g., impacts to an off-site grassland habitat eliminate rodents which causes a desirable owl population to leave the area). (28) Ecological risk assessment--The process that evaluates the likelihood that adverse ecological effects may occur or are occurring as a result of exposure to one or more stressors; however, as used in this context, only chemical stressors (i.e., COCs) are evaluated. (29) Ecological services--The physical, chemical, or biological functions of natural resources that one natural resource provides for another or to the public. Examples include provision of food, protection from predation, and nesting habitat, among others. (30) Ecological services analysis--A measurement of the potential change in ecological services based on considerations which may include, but are not limited to: the percent change in ecological services at the affected property that are attributable to COCs and/or potential response actions; the spatial extent of the affected property; and the recovery period. (31) Environmental medium--A material found in the natural environment such as soil (including non-waste fill materials), groundwater, air, surface water, and sediments, or a mixture of such materials with liquids, sludges, gases, or solids, including hazardous waste which is inseparable by simple mechanical removal processes, and is made up primarily of natural environmental material. (32) Exclusion criteria--Those conditions at an affected property which preclude the need to establish a protective concentration level for an ecological exposure pathway because the exposure pathway between the chemical of concern and the ecological receptors is not complete or is insignificant. (33) Exposure area--The smallest property surface area within which it is believed that exposure to chemicals of concern in soil or air by a receptor would be limited under reasonably anticipated current or future use scenarios. (34) Exposure medium--The environmental medium or biologic tissue in which or by which exposure to chemicals of concern by ecological or human receptors occurs. (35) Exposure pathway--The course that a chemical of concern takes from a source area to ecological or human receptors and includes a source area, a point of exposure, and an exposure route (e.g., ingestion), as well as a transport mechanism if the point of exposure is different from the source area. (36) Facility--The installation associated with the affected property where the release of chemicals of concern occurred. (37) Facility Operations Area--One or more areas (lateral and vertical extent) of an operational chemical or petroleum manufacturing plant with North American Industrial Classification System code numbers 325 or 324, respectively, with a hazardous waste permit or commission corrective action order within which response actions to multiple releases of COCs can be consolidated for purposes of compliance with this chapter on an area-wide basis by using interim or permanent response actions. The lateral extent of the facility operations area is limited to the contiguous area actively used for the development, manufacture, process, transfer, storage, and management of chemical or refinery products, hazardous materials, substances and wastes subject to Resource Conservation and Recovery Act regulation, and includes ancillary components such as, but not necessarily limited to, power plants and cooling units. (38) Feeding guilds--Groups of ecological receptors used to represent the variety of species that may be exposed to chemicals of concern at the affected property. The feeding guilds are generally based on function within an ecosystem, potential for exposure, and physiological and taxonomic similarity. Examples include carnivorous mammals, carnivorous birds, and piscivorous birds. (39) Functioning cap--A low permeability layer or other approved cover meeting its design specifications to minimize water infiltration and chemical of concern migration, and prevent ecological or human receptor exposure to chemicals of concern, and whose design requirements are routinely maintained. (40) Groundwater-bearing unit--A saturated geologic formation, group of formations, or part of a formation which has a hydraulic conductivity equal to or greater than 1 x 10-5 centimeters/second. (41) Groundwater production zone--The groundwater-bearing unit(s) which contributes water to a well. For example, if a well penetrates four distinct groundwater-bearing units isolated by competent aquitards, but the well is screened in only two of the units and has a competent annular seal to isolate the other two units, then the groundwater production zone consists of only the two units that contribute water to the well. (42) Groundwater protective concentration level exceedence zone--A protective concentration level exceedence zone within a groundwater-bearing unit. (43) Hazard index--The sum of two or more hazard quotients for multiple noncarcinogens originating from a single affected property. (44) Hazard quotient--The ratio of the level of exposure of a noncarcinogen acting through an individual or combined exposure pathway over a specified time period to a reference dose for the noncarcinogen derived for a similar exposure period. (45) Implementation Procedures--The most current version of Procedures to Implement the Texas Surface Water Quality Standards, as amended. (46) Innocent Owner or Operator--Those persons so designated in accordance with Texas Health and Safety Code, Chapter 361, Subchapter V, Immunity From Liability of Innocent Owner or Operator, as amended. (47) Institutional control--A legal instrument placed in the property records in the form of a deed notice, Voluntary Cleanup Program Certificate of Completion (VCP Certificate of Completion), or restrictive covenant which indicates the limitations on or the conditions governing use of the property which ensures protection of human health and the environment or equivalent zoning and governmental ordinances. (48) Judgmental sample--An investigative sample of an environmental medium which is purposefully located based upon property-specific information. (49) Laboratory Control Sample--A spiked blank sample analyzed by the laboratory to assess laboratory ability to successfully recover chemicals of concern from a control matrix. (50) Landscaped area--An area of ornamental, introduced, commercially installed, or manicured vegetation which is routinely maintained. (51) Long-term effectiveness--The ability of a remedy to maintain the required level of protection of human health and the environment over time. Cont'd... |
