The Colorado Oil and Gas Conservation Commission is the designated jurisdictional agency under subpart (g) of Part 271 of Title 18, Code of Federal Regulations. Pursuant to Section 271.705 of the Federal Energy Regulatory Commission regulations, under Section 107(b) of the Natural Gas Policy Act, the jurisdictional agency herewith submits its recommendation, as per Order Nos. NG-43-3 and NG-44-5, that the Niobrara formation underlying certain lands in Weld County, Colorado, be designated as a "tight formation" and incorporated into the list of "Tight Formations" established under Section 271.706 of the regulations. Pursuant to the guidelines established under Section 271.705(b)(l)(i)(ii)(iii), and the contents prescribed by 271.705(c), the Colorado Oil and Gas Conservation Commission submits the following:

1. Geological and geographical description of the Niobrara formation.

a. Commission Order No. NG-43-3 and NG-44-5.

2. Geologic and engineering data supporting the recommendation and the source of that data.

a. Transcript and exhibits from the public hearing held February 19, 1991.

3. A report to the extent to which existing state regulations will assure development of the recommended "tight formation" will not adversely affect any fresh water aquifers.

a. Colorado Oil and Gas Conservation Commission "Statement on Water Sand Protection".

b. A report from the State Engineer, Water Resources Investigation section, concerning water sand protection for the area has previously been submitted with NG-3-1 (Colo 1) and NG-29-1 (Colo 25).

c. State Rule No. 317.

4. Additional information.

a. Cause No. 407 established spacing and allowed commingling concerning the Niobrara formation in the area.

b. State Rule No. 318.

All geological and engineering testimonial evidence to support this recommendation has been received under oath. Copies of all documentary evidence received at the public hearing accompany this report. The requirements of 271.705(c) pursuant to 271.705(b)(l)(i)(ii)(iii) have now been met. The Oil and Gas Conservation Commission of the State of Colorado, therefore recommends, as per Order Nos. NG-43-3 and NG-44-5, that the Niobrara formation be designated as a "Tight Formation", in the area as described in said order, and having made such recommendation concludes its responsibility in the premises has been discharged.

OIL AND GAS CONSERVATION COMMISSION OF THE STATE OF COLORADO

BY Patricia C. Beaver, Secretary

PCB/dah

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STATEMENT OF WATER SAND PROTECTION

CAUSE NOS. NG-43 AND NG-44

ORDER NOS. NG-43-3 AND NG-44-5

Typical casing design of wells drilled in the area protects fresh water aquifers in the area as required by the rules and regulations of the Oil and Gas Conservation Commission of the State of Colorado. A description of an idealized-type casing program, and/or cementing program which will be used in wells drilled for production in the Niobrara formation was presented at the hearing. This plan was reviewed by representatives of the Office of the State Engineer, Water Resources Investigation Branch. All aquifers above the Niobrara formation will be behind pipe or protected by cement stage work, as required by State Rule No. 317, if these aquifers are below the shoe of the surface casing. State Rule No. 317 requires sufficient surface casing shall be run to reach a depth below all known or reasonably estimated utilizable fresh water levels. In areas where fresh water strata or zones are of such depth to make it impractical or uneconomical to set the full amount of surface casing necessary to cover or isolate all fresh water strata, the production string shall be stage cemented with a solid cement plug extending 50 feet below each fresh water strata to 50 feet above fresh water strata.

The Commission, therefore concludes that development of the recommended "tight formation" will not affect any fresh water aquifers that are, or are expected to be used as domestic, agricultural or other supplies.

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