New Mexico Administrative Code
Title 20 - ENVIRONMENTAL PROTECTION
Chapter 9 - SOLID WASTE
Part 9 - SOLID WASTE FACILITY GROUND WATER MONITORING SYSTEM PLAN AND GROUND WATER MONITORING PLAN; CORRECTIVE ACTION
Section 20.9.9.12 - ASSESSMENT MONITORING LEVELS
Current through Register Vol. 35, No. 18, September 24, 2024
A. Approved background ground water quality determinations shall be used as the baseline for determination of AMLs.
B. For all hazardous constituents, AMLs shall be 50 percent of the ground water protection standard.
C. If the background concentrations of any hazardous constituents is above 50 percent of the ground water protection standards, then the background concentration shall be the AML. Any statistically significant increase above the AML shall be an exceedence of the AML for that constituent.
D. If a ground water protection standard has not been established for a hazardous constituent, the AML shall be the background concentration or a 95 percent increase over the PQL of the constituent, whichever is greater.
E. For constituents identified in Subsections B and C of 20.6.2.3103 NMAC, the AMLs shall be 75 percent of the ground water protection standard, except pH, which shall be within the range of values shown in Subsection B of 20.6.2.3103 NMAC
F. If the background concentration of any constituent identified in Subsections B and C of 20.6.2.3103 NMAC is above 75 percent of the ground water protection standard, then the background concentration shall be the AML. Any statistically significant increase above the AML shall be an exceedence of the AML for that constituent.
G. If more than one toxic pollutant identified in 20.6.2.7 NMAC is detected, the toxic pollutant criteria of the commission rules for the combination of constituents shall be used to determine a ground water standard, using the methods described in Subsection I of 20.9.9.13 NMAC. The AML shall be 50 percent of the ground water standard, or the background concentration, whichever is greater. If the background concentration is greater than the ground water standard, then any statistically significant increase above the background concentration shall be an exceedence of the AML. However, this shall apply only in cases where such AMLs are more stringent than the AMLs otherwise determined under this section.