APPCOR13048

• Permit No: C1981034
• IBM Index Class Name: Application Correspondence
• Doc Date: 12/15/1981
• Doc Name: MEMO GRAND MESA COAL CO PERMIT APPLICATION ALLUVIAL VALLEY FLOORS
• From: JERRY ZIMPFER
• To: DAN MATHEWS
• Media Type: D
• Archive: No

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4. The applicant must provide information concerning subirrigation of
the lands in question. For these areas adjacent to the permit area,
a field reconnaissance to identify those areas where the vegetation
suggests subirrigation may be sufficient. For those areas within the
permit area, however, site specific information must be provided concerning
crop type, rooting depth, and alluvial water levels during the growing
season.
If the above information is not provided, the Division would go forward
with a "worst case" AVF determination. This would likely be that all
the area designated as Qgy is an Alluvial Valley Floor.
THE FOLLOWING INFORMATION WOULD BE REQUIRED ZF THE DIVISION DETERMINES
THAN AN ALLUVIAL VALLEY FLOOR EXISTS ZN OR ADJACENT TO THE PERh1IT AREA.
If Alluvial Valley Floors are identified, the applicant must submit
site-specific information concerning the productivity of the Alluvial
Valley Floor and the economic significance of the Alluvial Valley Floor
to the farm's production. In the absence of actual information, the worst
case assumption is that any Alluvial Valley Floors are significant to
agriculture.
In addition, the application must contain information describing the
surface and ground water that supply the Alluvial Valley Floor, and
identifying the essential hydrologic functions of the AVF. For any
Alluvial Valley Floor within the permit area the following must be
provided:
1. One year's baseline data for the quantity and quality of surface
and groundwater (for a perennial stream, gaging stations with continuous
recorders would be appropriate.),
2. A description of the exact nature of the hydrologic relationship
of surface water and groundwater (low flow investigations to determine
if the perennial stream is a yaining or a loosing stream would be appropriate.),
and
3. A description of the role of subirrigation in the Alluvial Valley
Floor including site-specific data on water table fluctuations during
the growing season (alluvial monitoring wells equipped with continuous
recorders would be appropriate).
Additional information could be required during the review process.
The data requirements might be less for Alluvial Valley Floors located
adjacent to the permit area.
The application should also include a plan to monitor the hydrology and
productivity of the Alluvial Valley Floor as required under Rule 4.24.