The following words and terms, when used in this subchapter, shall have the following meanings, unless the context clearly indicates otherwise.
  (1) Carcinogen--Substances which have been classified for human carcinogenic risk based on the United States Environmental Protection Agency's Weight of Evidence System of Carcinogenicity as Group A--Human Carcinogen; Group B--Probable Human Carcinogen; or Group C--Possible Human Carcinogen.
  (2) Carcinogen classification--The basis by which substances are classified for human carcinogenic risk based on the United States Environmental Protection Agency's Weight of Evidence System for Carcinogenicity: Group A--Human Carcinogen; Group B--Probable Human Carcinogen; Group C--Possible Human Carcinogen; Group D--Not Classifiable as to Human Carcinogenicity; and Group E--Evidence of Non-Carcinogenicity for Humans.
  (3) Long-term effectiveness--The ability of a remediation or corrective action to maintain over time the required level of protection of human health and the environment.
  (4) Nonresidential property--Any real property or portion of a property not currently being used for human habitation or for other purposes with a similar potential for human exposure, at which activities have been or are being conducted, having the primary Standard Industrial Classification (SIC) major group numbers 01-48 inclusive, 49 except 4941, 50-67 inclusive, 72-79 inclusive, 80 except 8051, 8059, 8062, 8063, 8069, 81 and 82 except 8211, 8221, 8222, 83 except 8351, 8361, 84-86 except 8661, 87-91 inclusive, 92 except 9223, and 93-97 inclusive. Nonresidential property includes all of the block(s) and lot(s) controlled by the same owner or operator that are vacant land, or that are used in conjunction with such business. For leased properties, nonresidential property includes the leasehold and any external tank, surface impoundment, septic system, or any other structure, vessel, contrivance, or unit that provides, or is utilized, for the management of contaminants to or from the leasehold.
  (5) Permanence/permanent/permanently--The property of achieving the maximum degree of long-term effectiveness and of enduring indefinitely without posing the threat of any future release that would increase the risk above levels established for the facility or area.
  (6) Point of exposure--A location where human or environmental receptors can come into contact with contaminants; also, a location which can be arbitrarily determined for purposes of estimating or measuring the concentration of contaminants available for exposure.
  (7) Practical quantitation limit/PQL--The lowest concentration of an analyte which can be reliably quantified within specified limits of precision and accuracy during routine laboratory operating conditions. The PQL minimizes to the extent possible the effects of instrument and operator variability and the influences of the sample matrix and other contaminants or substances upon the quantitation of the analyte. "Specified limits of precision and accuracy" are the criteria which have been included in applicable regulations or which are listed in the quality control sections of the analytical method. The PQL may be directly obtained or derived from the following sources with preference given to the most recent, scientifically valid method: federal regulations; EPA guidance documents; calculation from interlaboratory studies; and experimentally determined analytical methods not available from other existing sources.
  (8) Residential property--Any property that does not exclusively meet the definition of nonresidential property. Also, a portion of nonresidential property that is used in part for residential activities, such as a day care center, is defined as residential.
  (9) Systemic toxicant--Substances shown either through epidemiological studies or through laboratory studies to cause adverse health effects other than cancer.

Source Note: The provisions of this §335.552 adopted to be effective June 28, 1993, 18 TexReg 3814.