5 Colo. Code Regs. § 1002-41.6

Current through Register Vol. 47, No. 20, October 25, 2024

Section 5 CCR 1002-41.6 - POINT OF COMPLIANCE

A. In order to effect compliance with groundwater standards, one or more points of compliance shall be established. The term "point of compliance" shall be assumed to cover situations with one or several points of compliance. An activity shall comply with groundwater quality standards established under section 41.5 at the point of compliance. The establishment of a point of compliance shall not be required at the time of classification of any groundwater pursuant to section 41.4 . The point of compliance for those activities regulated by an implementing agency is discussed in subsection B of this section. Unless modified by the applicable implementing agency or the Commission, the criteria for establishing a point of compliance for the statewide standards established in section 41.5 are set forth in subsection (C) of this section. For those activities regulated by the Water Quality Control Division through permit or control regulations, the point of compliance shall be established under the provisions of subsection (D) of this section. Nothing in this regulation shall lessen the Division's existing authority to consider these groundwater standards when setting limits for surface water discharges which impact groundwater. The Commission may establish points of compliance in lieu of those established by the Division or this rule, on a case-by-case basis as described in subsection (E).

B. For the purposes of this subsection, the following agencies are referred to as "implementing agencies":

The Division of Reclamation, Mining and Safety; the State Engineer; the Oil and Gas Conservation Commission; and the state agencies responsible for activities related to the federal "Resource Conservation and Recovery Act of 1976", as amended, and related state programs.

Per the provisions of section 25-8-202 C.R.S., implementing agencies shall establish the point of compliance for those activities under their control. The points of compliance established in section 41.6 of this regulation shall not apply to activities regulated by an implementing agency, unless the Commission has determined after rulemaking that the point of compliance established by the implementing agency is not adequate to satisfy the requirements of section 25-8-202(7). The Commission may then establish, through rulemaking, a site-specific point of compliance which shall supersede any point of compliance established by the implementing agencies.

C. In the absence of a point of compliance established by the Division, and unless modified by the Commission in accordance with section 41.6 or subject to alternative regulatory requirements in accordance with section 41.5 , the point of compliance for the statewide standards established in section 41.5 shall be located as follows.

1. For facilities at which groundwater contamination existed as of September 30, 1989:

a. If the contamination is identified and reported to the division or other appropriate implementing agency on or before September 30, 1992, then the point of compliance shall be at whichever of the following locations is closest to the contamination source:

i. The site boundary; or

ii. The hydrologically downgradient limit of the area in which contamination exists when identified.

b. If the contamination is not identified and reported to the division or other appropriate implementing agency on or before September 30, 1992, then the point of compliance shall be at whichever of the following locations is closest to the contamination source:

i. The site boundary; or

ii. The hydrologically downgradient limit of the area in which contamination exists as of September 30, 1989; or

iii. If the location specified in (ii) can not be identified, then at the hydrologically downgradient limit of the area below the activity potentially impacting groundwater quality.

2. For all other facilities, at the hydrologically downgradient limit of the area below the activity potentially impacting groundwater quality.

D. Unless modified by the Commission in a site-specific hearing in accordance with section 41.6 , the point of compliance for those activities regulated by the Division through discharge permit regulations or control regulations shall be established by the Water Quality Control Division in accordance with the following criteria.

1. For all new and existing activities that discharge to groundwater the point of compliance will be set at the end-of-pipe or some distance hydrologically downgradient from the discharge, but no further than the site boundary. The point of compliance shall be set at the distance that provides the highest degree of protection that is technologically and economically feasible, based on an evaluation of the information as may be available regarding the following criteria:

a. The hydrologically downgradient limit of the area below the activity potentially impacting groundwater quality;

b. The classified use, established by the Commission, for any groundwater or surface water which could be impacted by contamination from the activity;

c. The geologic and hydrologic characteristics of the site, such as depth to groundwater, groundwater flow direction and velocity, soil types, surface water impacts, dilution, and climate;

d. The toxicity, mobility, and persistence in the environment of contaminants used or stored at the facility or discharged from the facility;

e. The hydraulic capacity of the wastewater treatment system;

f. The location of existing and potential future domestic use wells and established wellhead protection areas;

g. The location of other existing and potential beneficial uses of groundwater;

h. The treatment system design, including whether the design uses land treatment technologies or leachfields, and whether monitoring wells are appropriate and practical points of compliance;

i. The contamination or exceedance of water quality standards the activity has caused or has the potential to cause;

j. The potential of the site as an aquifer recharge area; and

k. Data and information related to technical and economic feasibility.

2. For surface water discharges that impact groundwater, the point of compliance shall be established in accordance with the provisions of the Colorado Discharge Permit System Regulations, Regulation No. 61 (5 CCR 1002-61).

E. When considering a request to adopt a site-specific point of compliance to apply in lieu of that established in subsection (C) or (D) above:

1. The Commission shall establish a more stringent site-specific point of compliance where determined necessary to protect human health and the environment, taking into account the potential for vertical migration of contamination, the number, quantity, nature, and persistence in the environment of the contaminants present, technological feasibility, economic reasonableness, upgradient levels of contamination, geohydrological data and features, the classified uses established by the Commission for any groundwater or surface water which would be impacted by contamination from the activity, and other environmental data or other relevant information as determined by the Commission; or

2. If the Commission determines that a less stringent point of compliance would protect human health and the environment, and the point of compliance established pursuant to subsection (C) or (D) is technologically infeasible or economically unreasonable, it shall establish an alternate site-specific point of compliance, taking into account the potential for vertical migration of contamination, the number, quantity, nature, and persistence in the environment of the contaminants present, technological feasibility, economic reasonableness, upgradient levels of contamination, point of use treatment, geohydrological data and features, the classified uses established by the Commission for any groundwater or surface water which would be impacted by contamination from the activity, and other environmental data or other relevant information as determined by the Commission.

5 CCR 1002-41.6

39 CR 11, June 10, 2016, effective 6/30/2016

39 CR 23, December 10, 2016, effective 12/30/2016

43 CR 11, June 10, 2020, effective 6/30/2020