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• UCREFRP Catalog Number: 7797
• Author: Collins, K.
• Title: Conceptual Management Plan for Razorback Sucker Habitat Enhancement in Flooded Bottomlands Scott M. Matheson Wetland Preserve Moab, Utah.
• USFW Year: 1994.
• Copyright Material: NO

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' 3. Soils and Geology
' The Windgate formation of red sandstone cliffs form the
geologic context of the Preserve. The Colorado River cuts
through steep cliffs of the Windgate formation and enters
' Moab Valley from the east at the north end of the Preserve.
The river crosses the valley flowing south, then exits the
valley through the steep cliffs at the southwest corner of
' the Preserve. Moab Valley lies along a fault zone. An
alluvial valley bottom overlays the salt cap of the Paradox
Formation. The Preserve is located in lower Moab Valley on
a complex of alluvial beds above the salt cap. The alluvium
' layer is 300 feet thick at some locations, but outcrops of
the salt cap occur near the eastern edges of the valley (M.
Ross pers. comm.).
The soils on the site are assorted Colorado River alluvial
sands, silts, and clays. The soils are generally alkaline
in nature as indicated by presence of salt tolerant plants.
Water analysis show that these salts are in the form of
calcium sulfate (gypsum salt dominated) which is expected
for this area (Cooper 1994).

Other water sampling by Cooper (1994) may indicate presence
of contaminants within the sediments. Sodium chloride (salt
water) is found in a ground water plume in the northern
portion of the Preserve. The source is presumably salt
springs from the Paradox formation on the east side of the
site. Heavy metals were also found in water samples, but
not in high concentrations. Lead occurred in the ground
water of the northwest area and also in the central
wetlands. Water contaminants are further discussed in the
water quality section below.
Two sediment samples from the central wetland area were
taken in July 1991 and were found to have concentrations of
selenium, vanadium, and zinc (Appendix B). Concentrations
were higher than typically found in this area, but were not
excessive.
Based on preliminary findings in the 1991 and soil and water
analysis by Cooper in 1993, further soil contaminant
investigations are being initiated. High levels of heavy
metals or salts may be present in water, but not pose a
problem in soils. A work plan for further soil contaminant
investigations is found in Appendix C.
conclusions: Sediment and some water samples contain higher
than normal heavy metal concentrations. Some water samples
contained high brine concentrations. Presence of these
contaminants may affect recovery of the razorback sucker.
Further investigations are being initiated.
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