REV93316

• Permit No: C1980003
• IBM Index Class Name: Revision
• Doc Date: 5/20/1999
• Doc Name: MEMO VERIFICATION THAT POND HG-8 AND POND 3 MEET PERMANENT IMPOUNDMENT REQUIREMENTS OF SECTION 4.05.
• From: DMG
• To: SL-03 FILE PHASE II/III BOND RELEASE APPLICATION HAYDEN GULCH MINE PN C-80-
• Type & Sequence: SL3
• Media Type: D
• Archive: No

Permanent Impoundment Checklist
Impoundment: Pond HG-S
Mine: Hayden Gulch Loadout Facility Date review completed: 5/20/99
Permit No.: C-92-081 CDMG reviewer: Tom Kaldenbach
Document where demonstration is located: SL-03 file
Intended use of impoundment: Postmining land use Of wildlife and livestock Watering
Demonstra
Demonstrations required by Section 4.05.9 (1) -lion Comment
adequate
(Yes / No)
(a) The quality of the impounded water shall be Monitoring data indicate a trend in quality that
suitable on a permanent basis for its intended will be suitable for livestock and wildlife use,
use, and discharge of water from the YeS and will comply with NPDES limitations,
impoundment shall meet applicable State and CWQCC basic surface water standards, and
Federal water ualit standards; CWQCC instream standards.
(b) The level of water shall be sufficiently stable This spoil spring-fed pond has maintained
and the configuration of the pond shall be 1'eS adequate level for intended use for several
ade uate to su ort the intended use; ears. Confi oration is ade uate for use.
(c) Adequate safety and access to Safety and access have been demonstrated by
impounded water shall be provided for yes historical and existing wildlife use.
ro osed water users;
(d) Water impoundments. shall no[ result in [he CDMG concluded that discharges from
diminution of the quality or quantity of water impoundment will not cause material damage
available to water right holders for agricultural,
I'eS to existing or future water users downstream
industrial. recreational, or domestic uses except (see CDMG letter of 12/18/98 in SL-04 file.
in accordance with applicable State law; Minimal seepage will cause negligible ground
water im acts.
(e) The design, construction and maintenance of CDMG verified compliance with Std. 378 in
permanent impoundments not meeting the size midterm review of 1984-5 (see CDMG letter of
requirements of 4.05.9(3) shall achieve the 11125/85 in Phase I bond release submittal) and
maximum design requirements of U.S. Soil verified again in current, SL-03, review. Vol.
Conservation Service Public Standard 378, 1'eS III, Appendix E of permit indicates Pond 003
"Ponds", Colorado, January, 1989. Copies of was designed and constructed in compliance
this publication are available at the office of the with Std. 378. Quarterly pond reports indicate
Division for public inspection. pond has been maintained in compliance with
Std. 378.
(f) The impoundment spillway system shall also be CDMG verified compliance with 4.05.6(3)(d)
designed in accordance with the requirements when the spillway was last modified (TR-66).
of Rule 4.05.6(3)(d) or 4.05.6(3)(e}. The design
event requirement of Rule 4.05.6(5)(b) shall be
applied for those impoundments not meeting YeS
the size or other criteria of Rule 4.05.9(3),
unless a larger design event is required by the
U.S. Soil Conservation Service Public Standard
378 Publication, Janu , 1989.
(g) The size of the impoundment is adequate for its YeS
intended u oses;
(h) The impoundment, will be suitable for the
YeS Current wildlife use indicates suitability for
a roved ostminin land use; and future wildlife and livestock use.
(i) The vertical portion of any remaining highwall There is no remaining highwall.
shall be located far enough below the low-
waterline along the full extent of highwall to YeS
provide adequate safety and access for the
ro osed water users.