Lise Marie Bisson, P.G

U.S. Environmental Protection Agency

Underground Injection Control Program (UIC), 8WD-SDU

1595 Wynkoop Street

Denver, Colorado 80202-1129

Telephone: (303) 312-6266

Email: This email address is being protected from spambots. You need JavaScript enabled to view it.

Re: Rangeview Metropolitan District, Class V Area Draft Permit, Arapahoe County, Colorado Draft Permit No. CO52414-00000, Comments Due 1-15-21

Dear Mr. Bisson,

Environmental Review, Inc. has reviewed the draft permit and has the following comments:

1)      Page 3 - Permit Considerations (40 CFR § 146.24) lacks a reference to the map that shows the injection wells and project area where the Rangeview Metropolitan District (RMD) is requesting a permit. In order to support necessary well evaluations, according to (40 CFR § 146.24) guidelines, the following proposed operational data needs to be included in this section: average and maximum daily rate and volume of fluids to be injected, average and maximum injection pressure, and source and an appropriate analysis of the chemical and physical characteristics of the injection fluid.

2)      Page 21 - Appendix J. More water quality data needs to be collected and analyzed. The water quality data is needed for Pilot Cycle Testing.  Additional constituents, such as those found in Appendix G and especially Volatile Organics and Semi-volatile organics, should be analyzed due to the possibility of mobilization from overlain strata, and unforeseen circumstances. The basis for requesting testing for volatile and semi-volatile organics is that some of the organic compounds are toxic to humans. For example, N-nitroso-dimethylamine is a volatile organic compound that is known to be highly hepatotoxic( toxins that affect the liver) to humans and animals.

3)      Page 21 - Part VII. Plugging and Abandonment Requirements (40 CFR § 146.10).This section needs to add the removal of any unused mud, liquid, gravel, and/or sludge from or adjacent to the well, per Best Management Practices.

4)      Page 14 & 15 - Part IV. Area of Review, Corrective Action Plan (40 CFR § 144.55), states that a corrective action plan is not required. This permit claims that a corrective action is unnecessary because wells will be cemented and cased to prevent the movement of fluids. What measures will you take to ensure the integrity of the well seal? Is it possible that fluid may migrate along a faulty well seal and contaminate lower aquifers or cause cascading that would drain the upper aquifer? How will you monitor that?  Due to these quality assurance concerns, please describe the methods that you will employ to ensure the integrity of  the well seal. In the event of failure, please describe what conditions will trigger the need for a corrective action.  and address the failure of the seal in this or other unforeseen situations.

5)      Page 17 - Section E, Additional Permit Requirements, subsection 3. Duty to Mitigate includes provisions for restoration of the area in the event that the injection wells become inactive or abandoned for two or more years. Please add a section that describes the processes and methods that will be used to restore the area to its original condition when they become unused/abandoned.

When responses to these comments are available, please email them to me at This email address is being protected from spambots. You need JavaScript enabled to view it.

Thank you,

Kazie Douglas (Associate in Colorado)

Environmental Reviewer

Environmental Review, Inc.

1792 Rogers Avenue

San Jose, CA  95112

www.envreview.org.

References

Agency for Toxic Substances & Disease Registry(ATSDRP).1989.Public Health Statement for n-Nitrosodimethylamine. References from https://www.atsdr.cdc.gov/phs/phs.asp?id=882&tid=173

Legal Information Institute.(1992).Legal Information Institute. https://www.law.cornell.edu/