As used in this part:

    (a) "NAPL" means a nonaqueous-phase liquid or a nonaqueous-phase liquid solution composed of 1 or more organic compounds that are immiscible or sparingly soluble in water. NAPL includes both DNAPL and LNAPL.

    (b) "Operator" means a person who is presently, or was at the time of a release, in control of, or responsible for, the operation of an underground storage tank system.

    (c) "Owner" means a person who holds, or at the time of a release who held, a legal, equitable, or possessory interest of any kind in an underground storage tank system or in the property on which an underground storage tank system is or was located including, but not limited to, a trust, vendor, vendee, lessor, or lessee.

    (d) "Property" means real estate that is contaminated by a release from an underground storage tank system.

    (e) "Public highway" means a road or highway under the jurisdiction of the state transportation department, a county road commission, or a local unit of government.

    (f) "Qualified underground storage tank consultant" means a person who meets the requirements established in section 21325.

    (g) "RBCA" means the American Society for Testing and Materials (ASTM) document entitled standard guide for risk-based corrective action applied at petroleum release sites, designation E 1739-95 (reapproved 2010) E1; standard guide for risk-based corrective action designation E 2081-00 (reapproved 2010) E1; and standard guide for development of conceptual site models and remediation strategies for light nonaqueous-phase liquids released to the subsurface designation E 2531-06 E1, all of which are hereby incorporated by reference.

    (h) "Regulated substance" means any of the following:

    (i) A substance defined in section 101(14) of title I of the comprehensive environmental response, compensation, and liability act of 1980, Public Law 96-510, 42 USC 9601, but not including a substance regulated as a hazardous waste under subtitle C of the solid waste disposal act, title II of Public Law 89-272, 42 USC 6921 to 6939e.

    (ii) Petroleum, including crude oil or any fraction of crude oil that is liquid at standard conditions of temperature and pressure (60 degrees Fahrenheit and 14.7 pounds per square inch absolute). Petroleum includes but is not limited to mixtures of petroleum with de minimis quantities of other regulated substances and petroleum-based substances composed of a complex blend of hydrocarbons derived from crude oil through processes of separation, conversion, upgrading, or finishing such as motor fuels, jet fuels, distillate fuel oils, residual fuel oils, lubricants, and petroleum solvents.

    (iii) A substance listed in section 112 of part A of title I of the clean air act, chapter 360, 84 Stat 1685, 42 USC 7412.

    (i) "Release" means any spilling, leaking, emitting, discharging, escaping, or leaching from an underground storage tank system into groundwater, surface water, or subsurface soils.

    (j) "Residual NAPL saturation" means the range of NAPL saturations greater than zero NAPL saturation up to the NAPL saturation at which NAPL capillary pressure equals pore entry pressure and includes the maximum NAPL saturation, below which NAPL is discontinuous and immobile under the applied gradient.

    (k) "Risk-based screening level" or "RBSL" means the unrestricted residential and nonresidential generic cleanup criteria developed by the department pursuant to part 201.

    (l) "Saturated zone" means a soil area where the soil pores are filled with groundwater and can include the presence of LNAPL.

    (m) "Site" means a location where a release has occurred or a threat of release exists from an underground storage tank system, excluding any location where corrective action was completed which satisfies the applicable RBSL or SSTL.

    (n) "Surface water" means all of the following, but does not include groundwater or an enclosed sewer, other utility line, storm water retention basin, or drainage ditch:

    (i) The Great Lakes and their connecting waters.

    (ii) All inland lakes.

    (iii) Rivers.

    (iv) Streams.

    (v) Impoundments.

    (o) "Site-specific target level" or "SSTL" means an RBCA risk-based remedial action target level for contamination developed for a site under RBCA tier II and tier III evaluations.

    (p) "Threat of release" or "threatened release" means any circumstance that may reasonably be anticipated to cause a release. Threat of release or threatened release does not include the ownership or operation of an underground storage tank system if the underground storage tank system is operated in accordance with part 211 and rules promulgated under that part.

    (q) "Tier I", "tier II", and "tier III" mean those terms as they are used in RBCA.

    (r) "Underground storage tank system" means a tank or combination of tanks, including underground pipes connected to the tank or tanks, which is, was, or may have been used to contain an accumulation of regulated substances, and the volume of which, including the volume of the underground pipes connected to the tank or tanks, is 10% or more beneath the surface of the ground. An underground storage tank system does not include any of the following:

    (i) A farm or residential tank of 1,100 gallons or less capacity used for storing motor fuel for noncommercial purposes.

    (ii) A tank used for storing heating oil for consumptive use on the premises where the tank is located.

    (iii) A septic tank.

    (iv) A pipeline facility, including gathering lines regulated under either of the following:

    (A) The natural gas pipeline safety act of 1968, Public Law 90-481, 49 USC Appx 1671 to 1677, 1679a to 1682, and 1683 to 1687.

    (B) Sections 201 to 215 and 217 of the hazardous liquid pipeline safety act of 1979, title II of Public Law 96-129, 49 USC Appx 2001 to 2015.

    (v) A surface impoundment, pit, pond, or lagoon.

    (vi) A storm water or wastewater collection system.

    (vii) A flow-through process tank.

    (viii) A liquid trap or associated gathering lines directly related to oil or gas production and gathering operations.

    (ix) A storage tank situated in an underground area such as a basement, cellar, mineworking, drift, shaft, or tunnel if the storage tank is situated upon or above the surface of the floor.

    (x) Any pipes connected to a tank that is described in subdivisions (i) to (ix).

    (xi) An underground storage tank system holding hazardous wastes listed or identified under subtitle C of the solid waste disposal act, title II of Public Law 89-272, 42 USC 6921 to 6939e, or a mixture of such hazardous waste and other regulated substances.

    (xii) A wastewater treatment tank system that is part of a wastewater treatment facility regulated under section 307(b) of title III or section 402 of title IV of the federal water pollution control act, 33 USC 1317 and 1342.

    (xiii) Equipment or machinery that contains regulated substances for operational purposes such as hydraulic lift tanks and electrical equipment tanks.

    (xiv) An underground storage tank system that has a capacity of 110 gallons or less.

    (xv) An underground storage tank system that contains a de minimis concentration of regulated substances.

    (xvi) An emergency spill or overflow containment underground storage tank system that is expeditiously emptied after use.

    (s) "Vadose zone" means the soil between the land surface and the top of the capillary fringe. Vadose zone is also known as an unsaturated zone or a zone of aeration.