New Mexico Administrative Code › Title 20 - ENVIRONMENTAL PROTECTION › Chapter 6 - WATER QUALITY › Part 4 - STANDARDS FOR INTERSTATE AND INTRASTATE SURFACE WATERS › Section 20.6.4.12 - COMPLIANCE WITH WATER QUALITY STANDARDS

Current through Register Vol. 35, No. 13, July 16, 2024
The following provisions apply to determining compliance for
				  enforcement purposes; they do not apply for purposes of determining attainment
				  of uses. The department has developed assessment protocols for the purpose of
				  determining attainment of uses that are available for review from the
				  department's surface water quality bureau.
A. Compliance with acute water quality
				criteria shall be determined from the analytical results of a single grab
				sample. Acute criteria shall not be exceeded.
B. Compliance with chronic water quality
				criteria shall be determined from the arithmetic mean of the analytical results
				of samples collected using applicable protocols. Chronic criteria shall not be
				exceeded more than once every three years.
C. Compliance with water quality standards
				for total ammonia shall be determined by performing the biomonitoring
				procedures set out in Subsections D and E of
				20.6.4.14
				NMAC, or by attainment of applicable ammonia criteria set out in Subsections K,
				L and M of
				20.6.4.900
				NMAC.
D. Compliance with the human
				health-organism only criteria shall be determined from the analytical results
				of representative grab samples, as defined in the water quality management
				plan. Human health-organism only criteria shall not be exceeded.
E. The commission may establish a numeric
				water quality criterion at a concentration that is below the minimum
				quantification level. In such cases, the water quality standard is enforceable
				at the minimum quantification level.
F. For compliance with hardness-dependent
				numeric criteria, hardness (as mg CaCO3/L) shall be
				determined from a sample taken at the same time that the sample for the
				contaminant is taken.
G.
Compliance schedules:
. The commission may allow the inclusion of a
				schedule of compliance in a NPDES permit issued to an existing facility on a
				case-by-case basis. Such schedule of compliance will be for the purpose of
				providing a permittee with adequate time to make treatment facility
				modifications necessary to comply with water quality based permit limitations
				determined to be necessary to implement new or revised water quality standards
				or wasteload allocation. Compliance schedules may be included in NPDES permits
				at the time of permit renewal or modification and shall be written to require
				compliance at the earliest practicable time. Compliance schedules shall also
				specify milestone dates so as to measure progress towards final project
				completion (e.g., design completion, construction start, construction
				completion, date of compliance).
H.
				It is a policy of the commission to allow a temporary standard approved and
				adopted pursuant to Subsection H of
				20.6.4.10
				NMAC to be included in the applicable federal Clean Water Act permit as
				enforceable limits and conditions. The temporary standard and any schedule of
				actions may be included at the earliest practicable time, and shall specify
				milestone dates so as to measure progress towards meeting the original
				standard.