The URL can be used to link to this page

Browse Search

Home My WebLink About981716.tiff Pee, 4 jlcra a _ — 3'a) P"ry ThttleApplegate,Inc. Consultants for Land,Mineral and Water Development September 8, 1998 Ms. Erica S. Crosby Division of Minerals& Geology 1313 Sherman Street,Room 215 Denver, CO 80203 RE: Kobobel Pit; Permit#M-98-043 Dear Erica: With the new publication scheduled,we understand that the public comment period ends on October 4, 1998. With the written objection entered in the application,we understand that there will not be a staff decision on that date. We are agreeable to the pre-hearing conference and the formal Board hearing to be held.on October 21 or 22, 1998. Prior to the Board hearing, it is my understanding that the staff will issue a recommendation on our application. With regard to the hydrologic balance question, we favor method A as a way to monitor decision. We do have several important points to make regarding the existing situation and a suggestion on a revised method of monitoring. First of all, it is important to note that Mr. Hopper has no legal claim to the groundwater underneath his so called"sub-irrigated" hay/alfalfa field. Mr, Hopper has no recorded water right,no decreed volume of diversion from the groundwater, and the State of Colorado makes no guarantees for stable groundwater table for anybody. Therefore,the potential impacts to the hydrologic balance relate to how a falling groundwater table might affect the natural vegetation, and not the sub-irrigated field: Potential impacts could be loss of natural vegetation in the ditch next to the field and subsequent erosion. The water requirements for natural vegetation extends from April through October. Through our observations,we contend that the water in the ditch(see Exhibit A)principally results from waste irrigation flows which proceed through the ditch, along the east side of the applicant's property, and dumps into the Rural Ditch. During the plant growing season, we believe these waste flows contribute to the groundwater and feed the plants rather than the groundwater feeding the plants. Also we believe that the groundwater level in the ditch and the adjacent sub-irrigated field may only marginally relate to the groundwater level within the permit boundary. 981716 _p ,� 11990 Grant Street, Suite 304•Denver, Colorado 80233• (303) 452-6611 • Fax (303)452-2759 Ms. Erica S. Crosby Division of Minerals & Geology September 8, 1998 Page 2 In order to better understand the situation, we agree that a piezometer should be installed at the southeast corner of the permit area and also that the water levels in the ditch should be monitored on a monthly basis. After one year of such observations,the applicant and the Division can more specifically understand the relationship between the groundwater and the waste flows. Then at a later consultation, we could determine what a reasonable drop of groundwater in the piezometer would be and what actions to minimize the impact to hydraulic balance would be appropriate. Since the applicant intends to start his mining operation in the late fall of this year,this consultation with one year of actual information could occur at the end of 1999. If you and Tom would like a site visit to confirm our observations, we would be happy to arrange that with you. We look forward to hearing from you regarding our suggestions. Cordially, TUTTLE APPLEGATE, INC. Gary J/uttle GJT/sjr Encs. cc: File#97-116M Bill Kobobel Weld County Clerk,via Certified Mail (Copy of DMG Ltr) Cog/1/ ?Fl- ((a....::,:. ‘ \ : 8 i. 1 0.1 1.70 I • :-.) —t ��• mk C\ 1 ®o •If.)...77_________\:W 1 "[ J 12 ivj1. • i V F O zto \J1\V III - m f Y ,s il V s- • noon C . S\fil ,INS.._------A_____NN.n... o: ii----- - ^ I3 b l cip/c,T • Y I 9 • dl \ `_•. ,,� ....----N �` $ Fes` n --Dees ��9 . o * I� to tea° a'-``'__'"_ " __ CA ci(3 o a' J \ -/----- " I-41 a ( o n I \ • I "' p W U �` �" I 1 Z V 1 O Y m Y n 2 .a m Y M W • VI �_— 0.3 CD p �T _ _. �✓_- _ _«: _ - gam = la 15 a L- -1 • jk i Willi, sli Niel '. ' i • 9 1 in o .- . Oooll (----1 /a. 1 c a w 'cy' 1 t^• a u' N „ 2 < O C i ,. , N N o `o o f ~ \� `� \n 1L--\\ `� \ a w u:, mz d a • - D o o n \ }hill l �ea.t� l� \�� ° 7 1� 3 v C Z c-7.1 °3 a5L® c/R\( a � J .. 1 L � 2 N CL Q ®OIL �-^1 ..'VVV 1 1��` �,yip U7 qJ .. L " p • • A� of., y. 1 '• aVl u' �°, y ao PP h ON o a a -.52- Y ^• y _ s. `' a.".- .� . Y t. n m .c it m n ti nn4-' c « m LO m m •woHoi -- 4 • �.., _ s F t 3 3 w 0 0 ri O LL m •--, `as 1 N • O � . ILA g O �v)6• © w $ OS/ 7/� ,-�' / • ( , r1 STATE OF COLORADO DIVISION OF MINERALS AND GEOLOGY Department of of Natural Resources ,1313 Sherman Room 215 Denver,Colorado 80203 Phone:(3031866-3567 866-6-3567 FAX:(303)832-8106 DEPARTMENT OF NATURAL August 31, 1998 RESOURCES Roy Romer Governor s. S ani Eastin TuttleApplegate Inc. l amess.Lochhead Executive Director 11990 Grant St., Suite 555 Michael B Long Denver, CO 80233 Division Director RE: Kobobel Pit, Permit No. M-98-043 Hydrology Review Dear Ms. Eastin, The Division of Minerals and Geology reviewed the adequacy response submitted by TuttleApplegate regarding hydrologic impacts to the Hopper's water well and subirrigated field from the Kobobel Pit mining operation. The Division concludes that there is a fair to moderate potential for the proposed mining operation to adversely affect the 8-acre subirrigated pasture owned by the Hopper's which is immediately south of Weld county Road 20 1/2. The internal memo is attached for your reference. The applicant must demonstrate that impact to the hydrologic balance of the surrounding area have been minimized, per Rule 3.1.6(1). This may be demonstrated by one of two methods; A. The operator will install a piezometer in the southeast corner of the permit area prior to excavation and will monitor the static water level at least once each month during periods of operation. Water level measurements taken will be incorporated into each year's Annual Report to be submitted to the Division. The operator will notify the Division immediately and cease all mining operations upon determination of a water level reading in excess of 2 feet. Mining may then resume following approval by the Division. OR, B. The operator will provide a groundwater investigation to verify that the proposed rate of pumping, expected drawdown rate, and expected cone of depression will not significantly affect the aquifer and water table surface that supports the 8-acre subirrigated pasture immediately south of Weld County Road 20 1/2. The groundwater investigation should identify the source of all data and equations or models used and should include at a minimum: 1. proposed pumping rate or rate needed to completely dewater the pit assuming a 12' depth, 2. expected drawdown rate of the groundwater surface at the pit, 3. groundwater elevation at the pit, 4. recharge rate of the aquifer form pit discharge, 5. expected drawdown of groundwater surface from crop use at subirrigated pasture, 6. expected rate, if significant, from other nearby wells, 7. expected recharge rate, if significant, from other nearby sources, 8. aquifer transmissivity, "T," 9. aquifer storage coefficient, "S," 10. horizontal distance from pit to subirrigated meadow, 11. calculated cone of depression, both horizontal and vertical extent, 12. analysis of results and possible impacts, and 13. if necessary, methods to be used for minimizing possible impacts. Please inform the Division as to which method will be used to demonstrate the impacts to the hydrologic balance of the surrounding area will be minimized, and incorporate it into the permit application. The Division received your written request for an extension to the decision date to October 5, 1998, in order to publish notice of the operation in accordance with Rule 1.6. The public comment period will end on October 4, 1998, which falls after the September 23-24, 1998 Board Hearing. In order to review any new comments or objections that may be submitted by October 4, 1998,the Pre-hearing Conference and Formal Board Hearing for the Kobobel Pit permit application will need to be scheduled around the October 21-22, 1998 Board Meeting. The operator will need to submit a written waiver of the right to a decision by October 4, 1998 in order for additional public comments and/or objections to be heard at the October 21-22, 1998 Board Meeting. If you have any questions, please do not hesitate to call. Since ly, (c� Erica S. Crosby Environmental Protection Specialist cc: Carl Mount, DMG Bruce Humphries, DMG Mr. William Kobobel Idaho Creek Gravel Company 7909 Weld County Road 5 Longmont, CO 80501 c:\esc\112app\M98043\980831 qg/ 7/(d • STATE OF COLORADO DIVISION OF MINERALS AND GEOLOGY Department of of Natural Resources pin 1h1nSherman St., Room 215 Denver,Colorado 80203 Phone:(303)866-6.35677 FAX:(303)832-8106 DEPARTMENT OF Date : August 27, 1998 NATURAL RESOURCES To : Erica Crosby, Carl Mount Roy Romer Governor lames S.Lochhead r From : Tom Schreiner rS Executive Director Michael B.Long Division Director RE: Kobobel Pit 112 Application, Hydrology Review, File No. M- 98-043 At your request I have reviewed the hydrologic aspects of the above mentioned application and adequacy response from Tuttle Applegate. I conclude that there is a fair to moderate potential for the proposed mining operation to adversely affect the 8-acre subirrigated pasture owned by the Hopper's which is immediately south of Weld County Road 20 1/2. The 600 foot exclusion rule as used by the Office of the State Engineer was implemented to minimize impacts to high production irrigation wells and does not seem to be appropriate in this case. For the purposes of this application, the applicant must demonstrate that impacts to the hydrologic balance of the surrounding area have been mimimized,per Rule 3.1.6(1). This may be demonstrated by one of two methods: A) The operator will install a peizometer in the southeast corner of the permit area prior to excavation and will monitor the static water level at least once each month during periods of operation. Water level measurements taken will be incorporated into each year's Annual Report to be submitted to the Division. The operator will notify the Division immediately and cease all mining operations upon determination of a water level reading in excess of 2 feet. Mining may then resume following approval by the Division. OR, B) The operator will provide a groundwater investigation to verify that the proposed rate of pumping, expected drawdown rate, and expected cone of depression will not significantly affect the aquifer and water table surface that supports the 8-acre subirrigated pasture immediately south of Weld County Road 20 1/2. The groundwater investigation should identify the source of all data and equations or models used and should include at a mimimum: 1. Proposed pumping rate or rate needed to completely dewater the pit assuming a 12' depth 2. Expected drawdown rate of the groundwater surface at the pit 3. Groundwater elevation at the pit 4. Recharge rate to the aquifer from pit discharge 5. Expected drawdown of groundwater surface from crop use at subirrigated pasture 6. Expected drawdown rate, if significant, from other nearby wells Q3/ 7/6 7. Expected recharge rate, if significant, from other nearby sources 8. Aquifer transmissivity, 9. Aquifer storage coefficient, "S" 10. Horizontal distance from pit to subirrigated meadow 11. Calculated cone of depression; both horizontal and vertical extent 12. Analysis of results and possible impacts 13. If necessary, methods to be used for minimizing possible impacts Fig 9,n/ 7/ 6, Hello