My WebLink
|
Help
|
About
|
Sign Out
Home
Browse
Search
SPDSS_Task43-2_Phase2_DenverBasinRegionAquiferProperty
CWCB
>
Decision Support Systems
>
DayForward
>
SPDSS_Task43-2_Phase2_DenverBasinRegionAquiferProperty
Metadata
Thumbnails
Annotations
Entry Properties
Last modified
4/17/2013 9:20:52 AM
Creation date
6/11/2008 11:57:10 AM
Metadata
Fields
Template:
Decision Support Systems
Title
SPDSS Task 43.2 - Denver Basin Region Aquifer Property - Phase 2
Description
This Technical Memorandum was undertaken under Task 43.2, and summarizes the compilation, analysis and mapping of existing published aquifer property data for the Denver Basin Region.
Decision Support - Doc Type
Task Memorandum
Date
2/13/2006
DSS Category
Groundwater
DSS
South Platte
Basin
South Platte
Contract/PO #
C153953
Grant Type
Non-Reimbursable
Bill Number
SB01-157, HB02-1152, SB03-110, HB04-1221, SB05-084, HB06-1313, SB07-122
Prepared By
CDM
There are no annotations on this page.
Document management portal powered by Laserfiche WebLink 9 © 1998-2015
Laserfiche.
All rights reserved.
/
67
PDF
Print
Pages to print
Enter page numbers and/or page ranges separated by commas. For example, 1,3,5-12.
After downloading, print the document using a PDF reader (e.g. Adobe Reader).
Show annotations
View images
View plain text
as a swamp. The relatively high values shown along the eastern margins of the aquifer <br />may reflect a bias in the specific capacity and laboratory test results, due to uncertainties <br />in aquifer saturated thickness and the collection of lab samples from outcrops, <br />respectively. The large range of values shown in Figures 5c and 5d are evidence of <br />potential bias in the results obtained from specific capacity and laboratory tests. <br />3.1.4 Upper Arapahoe Aquifer Hydraulic Conductivity Data <br />A total of 102 K values were obtained from the Upper Arapahoe Aquifer. The K values <br />range from 0.01 to 6.7 ft/day with a median value of 1.1 ft/day. The K data are <br />presented in Figure 9 and summarized statistically in Table 2. <br />As shown in Figure 9, the data indicate there is significant variability, which is typical of <br />fluvial deposits (Freeze and Cherry 1979). However, most of the data from aquifer <br />pumping tests are from Robson (1983), and, as indicated in Section 1.2, it is unknown <br />whether these test data are from the Upper or Lower Arapahoe Aquifer. Even so, there <br />does appear to be a zone of relatively higher K values along the southern edge of this <br />aquifer as shown by data from sources other than Robson (1983). This could indicate <br />proximity to a sediment source area to the south as described by Raynolds (2004) and a <br />more productive aquifer in the area of higher K values. <br />3.1.5 Lower and Undivided Arapahoe Aquifer Hydraulic Conductivity Data <br />A total of 426 K values were obtained from the Lower Arapahoe Aquifer, the second <br />largest number of data values available for any of the bedrock aquifers. The K values <br />range from 0.0003 to 42 ft/day with a median value of 1.2 ft/day. The K data are <br />presented in Figure 10 and summarized statistically in Table 2. <br />As shown in Figure 10, the data are highly concentrated in northern Douglas and <br />southwestern Arapahoe Counties, but there is a reasonable distribution of data in other <br />parts of the aquifer except for the area where Douglas, Elbert and El Paso Counties join. <br />The results from different types of tests (pumping, specific capacity, and laboratory) <br />show consistent results. The highest K values obtained from this aquifer are clustered in <br />an area in Northern Douglas County. <br />Lower K values are generally found in the northwest, southwest and eastern portions of <br />the aquifer. This spatial trend of high K values is consistent with a source for these <br />aquifer materials entering the current vicinity of the Denver Basin from a location in <br />western Douglas County. The region of high K values is also where the Arapahoe <br />Aquifer reaches its greatest thickness resulting in some of the greatest well yields from <br />the Denver Basin bedrock aquifers. This area is thought to be the location of a large <br />distributary fan deposit, the Wildcat Mountain Fan, resulting from the deposition of <br />sediments originating in mountains to the west (Raynolds 2004). <br />3.1.6 Laramie-Fox Hills Aquifer Hydraulic Conductivity Data <br />A total of 357 hydraulic conductivity values were obtained from the Laramie-Fox Hills <br />Aquifer. The K values range from 0.0004 to 262 ft/day with a median value of 0.5 <br />ft/day. The K data are presented in Figure 11 and summarized statistically in Table 2. <br />SPDSS Phase 2 Task 43.2 TM -Final 21 <br />2/ 13/ 2006 <br />
The URL can be used to link to this page
Your browser does not support the video tag.