INSPEC28554

• Permit No: M1980149
• IBM Index Class Name: Inspection
• Doc Name: MINERALS PROGRAM INSPECTION REPORT
• Inspection Date: 11/2/2000
• Media Type: D
• Archive: No

• (Page 2) •
MINE ID # OR PROSPECTING ID # M-80-149
INSPECTION DATE 11/2/2000
OBSERVATIONS
INSPECTOR'S INITIALS TAS
1. A site inspection was made of the Hokestra Pit No. 1 as part of an investigation of
various alluvial operations near the residence of John Roberts, located at 4789 WCR 24 3/9.
The Division had received a written complaint from Mr. Roberts on September 14, 2000
regarding declining water levels in his private lakes. (See attached letter). Present
during the site inspection was Greg Nelson of the Weld County Planning Department.
2. Prior to the site inspection, this inspector met privately with Mr. Roberts to evaluate
the nature of his complaint. Mr. Roberts concern is that the water levels in his private
lakes have dropped to their lowest level ever this year. Mr. Roberts has a total of 3 lakes
with a combined water surface of 19 acres. According to Mr. Roberts, the lakes were full as
of 1998. Since then, the water surface levels have dropped at least 24". Mr. Roberts
concern is that his lake water levels have been significantly and adversely affected by the
dewatering activities of the on-going mining operations at the Hokestra Pit No. 1.
Accordingly, Mr. Roberts has requested that the Division respond to his concern and evaluate
the hydrologic impacts of the adjacent operation.
3. Mr. Roberts further elaborated that the lakes he now owns were previously mined and
reclaimed by Weld County as part of the Hokestra Pit No. 1. (These lakes have been released
from further reclamation responsibility). Weld County currently has an approved water
augmentation plan from the Office of the State Engineer (OSE) for the reclaimed lakes (now
owned by Mr. Roberts) as well as existing pit disturbances. Mr. Roberts explained that Weld
County retained responsibility for ensuring adequate water rights for the three (3) private
lakes as part of their sales agreement.
4. Other hydrologic information conveyed by Mr. Roberts includes the following:
The 3 reclaimed lakes owned by Mr. Roberts are unlined and "fed" or recharged by alluvial
groundwater. They are immediately south and and range from within 100' to 1,500' of the
St. Vrain River. The lakes occur between the St. Vrain River and the Last Chance
irrigation ditch.
Groundwater in his property and surrounding area appears to flow from west to east, nearly
parallel with the flow of the St. Vrain River. Therefore, there is an assumption that
groundwater pumped from the alluvium at the Hokestra Pit No. 1 and discharged to the St.
Vrain is groundwater that would normally flow through the alluvium eastward toward Mr.
Roberts property and recharge his lakes.
Mr. Roberts expressed an interest in having Weld County install a temporary pipeline from
the Phase 2 area of the Hokestra Pit No. 1 to his lakes and discharge pit water to his
lakes to ensure adequate water levels. Once the water levels are adequate, any excess pit
water could then be discharged directly to the St. Vrain.
The Last Chance irrigation ditch is located immediately to the south of his property
(the ditch was flowing approximately 1/4 to 1/3 full at the time of inspection).
Based on drilling log information, there is a groundwater divide immediately south of Mr.
Roberts property comprised of a shale barrier approximately 13 feet below the ground
surface. Therefore, any mining related dewatering activities to the south should not have
an impact on Mr. Roberts lake water levels.