Section 335.568 - Appendix IIExamples of medium-specific concentrations (MSC), standards, and criteria for health-based closure/remediation (see § 335.558 of this title (relating to Medium Specific Concentration of Risk Reduction Standards Number 2.))
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(1) Concentrations for constituents are expressed in scientific notation. Examples 2.20E-00 = 2.2; 2.20E+02 = 220; and 2.20E-01 = 0.22.(2) The development of final cleanup levels may involve other factors as described in this subchapter, such as cumulative health effects, that are not considered in this chapter.(3) Groundwater concentrations are based on maximum contaminant levels (MCLs) or the formula and parameters for residential use of groundwater which are contained in § 335.567 of this title (relating to Appendix I). For nonresidential exposure conditions, the groundwater concentrations are calculated using the procedures of § 335.559(d)(2) or (3) of this title (relating to Medium Specific Requirements and Adjustments for Risk Reduction Standard Number 2).(4) For some constituents, the practical quantitation limit (PQL) may be the appropriate groundwater MSC as described in § 335.555(d)(1) of this title (relating to Attainment of Risk Reduction Standard Number 2: Closure/Remediation to Health-Based Standards and Criteria). See 40 Code of Federal Regulations Part 264 (Appendix IX) for a list of groundwater PQLs.(5) Residential soil groundwater protection concentrations are based on a multiplication factor of 100 times the groundwater MSC.(6) Industrial soil groundwater protection concentrations are based on a multiplication factor of 100 times the MCL or, when an MCL is not available, a factor of 100 times the groundwater concentration calculated using the formula and parameters which are contained in § 335.559(d)(2) or (3) of this title (relating to Medium Specific Requirements and Adjustments for Risk Reduction Standard Number 2).(7) Residential soil concentrations (maximum) are calculated using the formula and parameters for residential land use which are contained in § 335.567 of this title (relating to Appendix I). The person must also demonstrate that groundwater is protected and that no nuisance conditions exist (§ 335.559(a)-(h) of this title (relating to Medium Specific Requirements and Adjustments for Risk Reduction Standard Number 2)).(8) Industrial soil concentrations (maximum) are calculated using the formula and parameters for industrial land use which are contained in § 335.567 of this title (relating to Appendix I). The person must also demonstrate that groundwater is protected and that no nuisance conditions exist (§ 335.559(a)-(h) of this title (relating to Medium Specific Requirements and Adjustments for Risk Reduction Standard Number 2)).(9) The final, proposed or listed MCL, from the Federal Safe Drinking Water Act, §146. For lead, the action level for lead in drinking water is used as the MSC.(10) All concentrations were calculated using data from the Integrated Risk Information System (IRIS) Chemical Files, or data from the Health Effects Assessment Summary Tables (HEAST), developed by the United States Environmental Protection Agency, Office of Research and Development and Office of Health and Environmental Assessment, Washington, D.C.20460. The toxicity information, and the MSCs, will be updated as new information becomes available.(11) In some cases, an oral reference dose (RFD) or an oral slope factor (SF) was substituted for the inhalation RFD or inhalation SF in calculating MSC. This MSC will be updated when this information becomes available.(12) The MSCs calculated for this compound are based on noncarcinogenic effects. The following formula was used for calculating the soil MSCs: MSC = [(oral RFD)(Body Weight)(ED)(365 days/yr)]/[(EF)(ED)(IR)(CF)]. For residential soils, the following exposure factors were used: BW = 15 Kg; ED = 5 years; EF = 350 days/year; IR = 200 mg/day. For industrial soils, the following exposure factors were used: BW = 70 Kg; ED = 25 years; EF = 250 days/year; IR = 100 mg/day. In both cases, the CF is 0.000001 kg/mg. When oral slope factors become available, these MSCs will be revised.(13) As described in § 335.559(e) of this title (relating to Medium Specific Requirements and Adjustments for Risk Reduction Standard Number 2), the sum of concentrations of the volatile organic compounds in vapor phase in soil shall not exceed 1,000 ppm by weight or volume.(14) The MSC for lead in soil is based on values calculated by the United States EPA using the Lead Uptake/Biokinetic Model, Version 0.4, which has been developed by the United States EPA Office of Health and Environmental Assessment.(15) Soil MSCs for polychlorinated biphenyls are based upon the 4/2/87 TSCA regulations, 40 Code of Federal Regulations §761.125 (see 52 FedReg 10688).(16) NHHB = Not Human Health Based. The SAI-Ind MSC for this compound exceeds 10e+6 ppm, which means it is not toxic to humans when exposed to soils under these assumptions. Persons must consider other criteria of § 335.559 of this title (relating to Medium Specific Requirements and Adjustments for Risk Reduction Standards Number 2) to develop numeric cleanup values.30 Tex. Admin. Code § 335.568
The provisions of this §335.568 adopted to be effective June 28, 1993, 18 TexReg 3814