Browsing by Author "Alexander, Scott C"
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Item Ahrensfeld Creek and Borson Northeast Dye Trace Report 2007-2010 Winona County, MN(2017) Green, Jeffrey A; Alexander Jr., E. Calvin; Alexander, Scott C; Luhmann, Andrew J; Runkel, Anthony C; Peters, Andrew JSoutheastern Minnesota’s karst lands support numerous trout streams. These trout streams are formed by springs discharging from Paleozoic bedrock. Dye tracing has been the tool of choice for mapping the springsheds (karst groundwater basins) that feed these springs. Previous work was focused on the Galena limestone karst. In order to accelerate springshed mapping, a two-year study was funded by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR). Across southeastern Minnesota, numerous springs discharge from the Cambrian St. Lawrence formation. The St. Lawrence is considered to be a confining unit under the Minnesota well code. A dye trace was initiated when a stream sink was discovered in the upper St. Lawrence Formation. The sampling points included springs, stream crossings, and a municipal well that may be at risk for surface contamination. Dye was recovered at one spring in less than two weeks and at two other springs in less than three weeks. This translates into travel times of 200-300 meters/day. The springs all discharge from the lower St. Lawrence Formation. The St. Lawrence contains beds of dolostone; the dye trace demonstrates that there is a karst conduit flow component in this formation. This is evidence that these springs are significantly more susceptible to degradation than previously thought.Item Bear Spring, Olmsted County, Minnesota; April 2018 Dye Trace and 2016-2018 Spring Monitoring Report(2019-01-29) Barry, John D; Larsen, Martin R; Tipping, Robert G; Alexander, Scott C; Alexander Jr, E CalvinItem Carbon-14 Age Dating Calculations for Minnesota Groundwaters(2018) Alexander, Scott C; Alexander, E Calvin Jr.Groundwater dating techniques can be applied to flow systems with time scales from hours to tens of millennia. For the purposes of this report age and residence time are used interchangeably. For waters with ages ranging up to about 30,000 to 40,000 years carbon-14 (14C), or radiocarbon dating, can be a useful technique (Han et al., 2012). Han and Plummer (2013, 2016) reviewed 14C groundwater dating models. In particular, converting a measured 14C activity to an “age” is complicated by exchange of carbon in surficial, soil, and groundwater environments. Groundwater age is, however, not defined by simple piston flow past an arbitrary point like a well. Mixing occurs at several scales from advection and dispersion along a single flow path, to mixing of multiple flow paths, to mixing within a borehole intersecting multiple aquifers. In practice all groundwaters are a mixture of waters with varying subsurface residence times (Bethke and Johnson, 2008; Cartwright et al., 2017). Efforts to reconcile complex geochemistry and flow paths with geochemical models and calculations have been made by many; classic efforts include Deines et al. (1974), Wigley et al. (1978), Plummer et al. (1990), ranging to work by Coetsiers and Walraevens (2009). This document outlines field and analytical techniques we have used to acquire the carbon isotopic data from nearly 700 wells in Minnesota. Determinations of the ages or residence times of Minnesota groundwaters are widely used in scientific and management studies all around Minnesota (Alexander and Alexander, 1989). In a typical county atlas about 100 wells are measured for groundwater chemistry, stable isotopes of hydrogen (H) and oxygen (O), and tritium content. A selection of about ten water wells with no measurable tritium are then resampled for the radioactive isotope carbon-14 (14C) and the stable isotopes carbon-13 (13C) and carbon-12 (12C). Three major groups of studies have been conducted in Minnesota. Many original analyses were done as part of research on groundwater age in the Mt. Simon aquifer and were extended with a radium study (Lively et al., 1992) with funding in large part by Legislative Committee on Minnesota Resources (LCMR). At this same time a variety of small-scale studies were conducted in a variety of geologic settings across Minnesota. The United States Geological Survey (USGS) oversaw several projects to define “flow tubes” in selected aquifers across Minnesota (Delin, 1990; Smith and Nemetz, 1996) also with LCMR funding. The Minnesota Department of Natural Resources (DNR) as part of the County Atlas Program and Mt. Simon recharge studies (Berg and Pearson, 2012) has conducted 14C age dating with significant support from the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR) with additional funding from the Clean Water Fund.Item Dye Trace Report Gorman Creek Trace: March 2011 Wabasha County, Minnesota(2017-02) Green, Jeffrey A; Luhmann, Andrew; Alexander, Scott C; Wheeler, Betty J; Alexander Jr., E. CalvinThe karst lands of southeast Minnesota contain more than one hundred trout streams that receive perennial discharge from Paleozoic bedrock springs. Several of the Paleozoic bedrock aquifers that provide discharge to these streams are dominated by conduit-flow. Field investigations into the flow characteristics of these aquifers have been conducted using fluorescent dyes to map groundwater springsheds and characterize groundwater flow velocities for use in water resource protection. Gorman Creek is one of these designated trout streams. The creek is located roughly 14 kilometers (8.5 mi.) northeast of Plainview, Minnesota in Wabasha County (Figure 1). This trace was completed to add to delineated springsheds of the region as part of the Environmental and Natural Resources Trust Fund (ENRTF) Springshed Mapping project.Item Dye Trace Report Harmony, Minnesota Area Traces: October 2007, June 2009, and November 2010 Fillmore County, Minnesota(2016-06) Green, Jeffrey A; Peters, Andrew J; Luhmann, Andrew J; Alexander, Scott C; Wheeler, Betty J; Alexander Jr., E. CalvinDye traces were conducted in the area of Harmony, MN in southern Fillmore County as part of the Environmental and Natural Resources Trust Fund (ENRTF) Springshed Mapping project. The traces described in this report were conducted to improve the delineation of the springsheds in the Harmony area. This report covers traces completed in October 2007, June 2009, and November 2010. Tracing had been completed in the vicinity previously for the ENRTF-Springshed project in the spring of 2008 (Green et al., 2008) and fall of 2008 (Green et al., 2009); as part of the ENRTF-Hydraulic Impacts of Quarries and Pits project from 2002-2004 (Green et al, 2003); in 1997 (Alexander et al, 1997); during the Fillmore County Geologic Atlas Project in 1993 and 1994 (Alexander et al, 1995); and for earlier work summarized in Alexander and others (1995) and by Kingston (1943).Item Dye Trace Report on the Groundwater Springsheds of Roaring Spring and Frego Creek near Canton, Minnesota; Traces: September 2009, March 2010, and February 2011; Fillmore County, Minnesota(2016-02) Green, Jeffrey A; Luhmann, Andrew; Alexander, Scott C; Wheeler, Betty J; Alexander Jr., E. CalvinDye traces were conducted in and around the area of Canton, MN in southern Fillmore County as part of the Environmental and Natural Resources Trust Fund (ENRTF) funded Springshed Mapping project. This report covers traces done in September 2009, March 2010, and February 2011. Tracing had been done in the area previously in the spring of 2008 (Green et al., 2008) and 2009 (Green et al., 2009) under the auspices of the ENRTF-Springshed Project, spring of 2007 for the South Fork Root River watershed project (Green, 2007), in 1993 and 1994 during the Fillmore County Geologic Atlas Project and earlier work summarized in Alexander et al. (1995) and by Kingston and Janssen (1941).Item Dye Tracing Sewage Lagoon Discharge in a Sandstone Karst, Askov, Minnesota(Proceedings of the 10th Multidisciplinary Conference on Sinkholes and the Engineering and Environmental Impacts of Karst. © 2005 American Society of Civil Engineers. Published online: April 26, 2012, 2005-09-28) Alexander Jr., E. Calvin; Alexander, Scott C; Piegat, James J; Barr, Kelton D; Nordberg, BradAn investigation of the sandstone karst at Askov, Pine County, Minnesota was conducted utilizing fluorescent dye tracing techniques. Connections were documented between the effluent from WWTF lagoons discharged into a sinking stream and local residential water supply wells southwest of the stream sink, over kilometer-scale distances. The apparent velocity of dye from the steam sink to the residential well was 57 m/day, much faster than would be expected for porous-media flow in a sandstone but slower than expected for well-developed conduit karst in carbonate rock. The traces also document stage-dependent, divergent flow to the northeast and west from recharge to a sinkhole adjacent to the lagoons. A well-developed conduit system extends a few hundred meters under the northern portion of the lagoons with flow velocities greater than 128 m/day to the northeast. A slower flow system extends for at least a kilometer to the west and northwest with a range of apparent flow velocities that average about 9 m/day. The slower flow system reached a broad “fan” of residential wells to the west but was not detected in other wells in the same direction.Item Dye Tracing to Camp Coldwater Spring, Minneapolis, MN(Minnesota Ground Water Association Newsletter Volume 20 Number 4: December 2001 Page 4 - 6. Additional results from Sophie Kasahara's Senior Thesis "A Hydrological Study of Coldwater Spring, Minneapolis, MN." - UM Geoengineering Department, 2016., 2017-06) Alexander Jr., E. Calvin; Alexander, Scott C; Barr, Kelton D; Kasahara, Sophie M; Wheeler, Betty JCamp Coldwater Spring is a ~6.3 liter/sec spring that emerges from a Platteville Limestone ledge at the top of the west side of the Mississippi River gorge. It was the original water supply for Ft. Snelling in the early-mid 1800’s and is a registered Minnesota State Landmark. Potential impacts from nearby highway construction led to two successful dye traces to help define the groundwater basin feeding the spring. These traces are the first traces through the Platteville in the Twin Cities. Dye input trenches were dug with a backhoe to the top of the water table. Input B reached the top of the Platteville and the water table was a few inches above the bedrock surface. Eosin dye input into the trench reached Camp Coldwater Spring, 125 meters away in less than 1.5 hours. The minimum flow velocity in the fractured Platteville Limestone was 83 m/hr. Input C reached the water table while still in glaciofluvial sediments and was 305 meters from the spring. Fluorescein dye from Input C reached the spring in 16 days. The slower flow velocity is a combination of flow through the glaciofluvial sediments and through the fractured Platteville Limestone. These two positive traces demonstrate that Inputs B and C are inside the ground-watershed that supplies the Spring and support concerns about the potential impact of dewatering and construction activities on the Spring. The trace is ongoing.Item Dye Tracing Within the St. Lawrence Confining Unit in Southeastern Minnesota(Proceedings of the 11th Multidisciplinary Conference on Sinkholes and the Engineering and Environmental Impacts of Karst. © 2008 American Society of Civil Engineers. Published online: June 20, 2012, 2008-09-26) Green, Jeffrey A; Luhmann, Andrew J; Peters, Andrew J; Runkel, Anthony C; Alexander Jr., E. Calvin; Alexander, Scott CSoutheastern Minnesota’s karst lands support numerous trout streams. These trout streams are formed by springs discharging from Paleozoic bedrock. Dye tracing has been the tool of choice for mapping the springsheds (karst groundwater basins) that feed these springs. Previous work was focused on the Galena limestone karst. In order to accelerate springshed mapping, a two-year study was funded by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative- Citizen Commission on Minnesota Resources (LCCMR). Across southeastern Minnesota, numerous springs discharge from the Cambrian St. Lawrence formation. The St. Lawrence is considered to be a confining unit under the Minnesota well code. A dye trace was initiated when a stream sink was discovered in the upper St. Lawrence Formation. The sampling points included springs, stream crossings, and a municipal well that may be at risk for surface contamination. Dye was recovered at one spring in less than two weeks and at two other springs in less than three weeks. This translates into travel times of 200- 300 meters/day. The springs all discharge from the lower St. Lawrence Formation. The St. Lawrence contains beds of dolostone; the dye trace demonstrates that there is a karst conduit flow component in this formation. This is evidence that these springs are significantly more susceptible to degradation than previously thought.Item Forestville North Dye Trace: September 5, 2008 to November 12, 2008(2008) Green, Jeffrey A; Peters, Andrew J; Luhmann, Andrew J; Alexander Jr., E. Calvin; Alexander, Scott CA dye trace was conducted in an area near Forestville State Park in Minnesota from September 5, 2008 to November 12, 2008 (Figure 1). Numerous dye traces have been completed in this area in the past and this effort was made in order to better delineate the springsheds in this area due to the close proximity of numerous State of Minnesota designated trout streams. Achieving a better understanding of the connection of these sinkholes receiving surface water flow and their connectivity to springs that provide a cold water source for the designated trout streams in the area was the goal of this trace. However, the goal of this trace was two‐fold, one sinkhole that received dye, Minnesota Karst Feature Database number 23:D2474, had previously been studied and was shown to be connected to cold water sources for two trout streams. The previous dye trace was completed during wet, spring conditions and this trace was completed during a much drier time in the late fall. Completing the trace during these differing conditions may help to better understand the seasonal changes of the subsurface flow of groundwater.Item Frego Creek Dye Trace: March 11, 2008 to June 16, 2008(2008) Green, Jeffrey A; Peters, Andrew J; Luhmann, Andrew J; Alexander Jr., E. Calvin; Alexander, Scott CA dye trace was conducted in an area near the city of Canton, Minnesota from March 11, 2008 to June 16, 2008. Dye traces have been completed in this area in the past and this effort was made to further refine delineation the springsheds in this area due to the close proximity of Frego Creek, a Minnesota designated trout stream. Much of the city of Canton’s stormwater flows to sinkholes throughout the city limits and some just outside of city limits. Achieving a better understanding of the connection of these sinkholes receiving this stormwater flow and their connectivity to springs that provide a cold water source for Frego Creek was the goal of this trace.Item Frego Creek Spring 2009 Dye Trace: March 6, 2009 to May 5, 2009(2009) Green, Jeffrey A; Peters, Andrew J; Luhmann, Andrew J; Alexander Jr., E. Calvin; Alexander, Scott CA dye trace was conducted in an area near the city of Canton, Minnesota from March 6, 2009 to May 5, 2009. Dye traces have been completed in this area in the past and this effort was made to further refine delineation the springsheds in this area due to the close proximity of Frego Creek, a Minnesota designated trout stream. Much of the city of Canton’s stormwater flows to sinkholes throughout the city limits and some just outside of city limits. Achieving a better understanding of the connection of these sinkholes receiving this stormwater flow and their connectivity to springs that provide a cold water source for Frego Creek was the goal of this trace.Item From spring to stream: water quality analysis in Trout Brook, Dakota County, MN(2018-04) Pencak, Edward S; Alexander, Scott C; Alexander, E CalvinItem Harmony Fall 2008 Dye Trace(2009) Green, Jeffrey A; Peters, Andrew J; Luhmann, Andrew J; Alexander Jr., E. Calvin; Alexander, Scott CA dye trace was conducted in an area in the City of Harmony, Minnesota, and an area located just west of the City of Harmony, Minnesota from October 28, 2008 to May 4, 2009 (Figure 1). Numerous dye traces have been completed in this area in the past and this effort was made in order to better delineate the springsheds in this area due to the close proximity of numerous State of Minnesota designated trout streams. Achieving a better understanding of the connection of these sinkholes receiving surface water flow and their connectivity to springs that provide a cold water source for the designated trout streams in the area was the goal of this trace.Item Harmony Spring 2008 Dye Trace(2008) Green, Jeffrey A; Peters, Andrew J; Luhmann, Andrew J; Alexander Jr., e; Alexander, Scott CA dye trace was conducted in an area in the City of Harmony, Minnesota from May 6, 2008 to June 13, 2008 (Figure 1). Numerous dye traces have been completed in this area in the past and this effort was made in order to better delineate the Buggywhip, Hart, and the Big Spring springsheds in this area due to the close proximity of numerous State of Minnesota designated trout streams. Achieving a better understanding of the connection of these sinkholes receiving surface water flow and their connectivity to springs that provide a cold water source for the designated trout streams in the area was the goal of this trace.Item Indian Springs Creek Dye Trace Report Houston County, Minnesota(2017-03) Green, Jeffrey A; Luhmann, Andrew J; Alexander, Scott C; Wheeler, Betty J; Alexander Jr., E. CalvinItem June 1997 Highway 44--Odessa Spring Traces(1997-07-23) Alexander, Scott C; Alexander Jr., E. CalvinOn June 6 1997, three dye traces were initiated from sinkholes D6741, D6742, and D6743 which are located on the north edge of Highway 44. The sinkholes are 2.23, 1.28, and 0.38 miles west of Highway 44's junction with Minn. Highway 139 on the south edge of Harmony Minn. Flow from sinkholes D6741 and D6742 resurged at Odessa Spring in four to six days. Odessa Spring is on the Upper Iowa River about 3.5 miles southwest of that segment of Highway 44. The third dye washed into sinkhole D6743 was not detected as any of the monitoring sites as of July 8, 1997. None of the dyes were detected in the upper or lower underground streams in Niagara Cave.Item Lewiston Interchange Dye Trace Report Winona County, Minnesota(2017-03) Green, Jeffrey A; Peters, Andrew J; Luhmann, Andrew J; Alexander, Scott C; Wheeler, Betty J; Alexander Jr., E. CalvinItem Optical Brighteners: Sorption Behavior, Detection, Septic System Tracer Applications(Published in: Proceedings of the International Association of Hydrogeologists XXVI International Congress, Edmonton, Alberta, Canada. June 1995., 1995-06) Fay, Steffan R; Spong, Ronald C; Alexander, Scott C; Alexander Jr., E. CalvinLaboratory soil column experiments were used to evaluate the optical brighteners (fluorescent whitening agents) Tinopal3 CBS-X (ASTM designation DSBP-1) and Tinopal3 5BM-GX (ASTM designation DASC-4) and the fluorescent dye eosin Y (C.1. 45380) as adsorbing tracers in subsurface systems. In a low organic carbon content glacial outwash sand (foe = 0.0034, 97% sand by weight) the solid-water distribution coefficient (Kd) was determined to be 0.26 cm113/g for Tinopal CBS-X, 0. 78 cm113/g for Tinopal 5BM-GX, and 0.024 cm11 3/g for eosin Y. All three compounds had simple sigmoidal breakthrough curves. Optical brighteners can be detected in direct solution by fluorometry but suffer from interference associated with naturally occurring organic compounds. Unbrightened cotton can be used to qualitatively detect optical brighteners. Polyethersulfone filter media can be used to selectively remove optical brighteners from solution without changing the background fluorescence spectrum. The exposed filter medium can be analyzed as a solid sample in a scanning spectrofluorophotometer. The resulting spectrum can be used to measure the optical brightener concentration in the filtered sample. Polyethersulfone filters can be used to detect optical brighteners in samples collected in and around septic system drain fields at less than 1 ppb Tinopal 5BM-GX equivalent.Item Ostrander Dye Trace Report Fillmore County Minnesota Traces: 17 May 1993(2018-01) Rutelonis, J. Wes; Alexander, Scott C; Green, Jeffrey A; Barry, John D; Alexander Jr., E. Calvin