|Beginning on 03 March 2023, the analog modem telemetry is no longer supoorted at this site. We are working on a solution to get this site to transmit data again, but there will likely be a delayed effort. Data are still actively being recorded at this site, but they are not being transmitted. Data will be manually downloaded periodically and loaded into the database.|
|Bemidji Toxics Research Site Well 310D|
|Township:||Lamers (T147N R35W)|
|Location:||In forest, 3.7 miles north of US Hwy. 2, 2.3 miles SE of Pinewood, MN|
|Land-surface elevation:||1422.63 ± 0.01 feet, NAVD88|
|Installation:||May 01, 1985, for the Bemidji Toxics Research Site|
|Open interval:||30.08–33.08 feet|
|Original and current use:||Monitoring, for the U.S. Geological Survey|
|Type:||Hydrologically unconfined sand and gravel|
|Thickness:||>35.25 feet (0.00–>35.25 feet, BLS)|
|Deposit:||Glacially deposited sand and gravel|
This site is operated in cooperation with the U.S. Geological Survey's Toxic Substances Hydrology Program, Minnesota Pollution Control Agency, Enbridge Energy Inc., and Beltrami County.
Water levels below land surface are accurate to 0.01 feet. Water levels above National American Vertical Datum of 1988 (sea level) are calculated by subtracting recorded water levels from the land surface elevation, which is accurate to ± 0.01 feet based on a differential GPS survey. Water-level differences are accurate to within 0.01 feet.
Water temperature during 21 Mar. 2007 at 00:00 CDT to 19 Nov. 2015 at 07:00 CST (measured with KPSI 500 transducer) were accurate to 0.3°C, due to noisiness in the water temperature record. Differences in temperature were accurate to 0.3°C. Water temperature during 19 Nov. 2015 at 08:00 CST to the present (measured with WaterLOG H-3123 transducer) are accurate to 0.1°C. Differences in temperature are accurate to 0.1°C.
Soil temperature is accurate to 0.1°C, and differences in temperature are accurate to 0.1°C.
Soil moisture is accurate to 3%, and differences in soil moisture are accurate to <0.05%. The sensors used to record soil moisture at these sites measure liquid water. When soil water freezes in the vicinity of the sensors, the sensors record an apparent decrease in soil moisture. This apparent decrease in soil moisture is caused by the sensors inability to detect frozen water rather than actual changes in soil water content. At nearby sites, the uppermost sensor (0-30cm), soil moisture values are variably affected by freezing beginning with the onset of soil frost in the fall and continuing through spring thaw. It is difficult to ascertain how much of the soil moisture changes during the fall to spring periods are due to freezing/thawing of soil water versus infiltration of precipitation or thawing snow. At this site, the sensor installed at 150cm has a much more pronounced decrease in soil moisture when soil water freezes, followed by a subsequent sharp increase when soil water thaws.
Specific conductance is accurate to 5%.
Precipitation is accurate to 0.01 inches except during freezing periods (about Dec. through early Apr.). The rain gage is unheated and uncovered. The precipitation data during freezing periods result from melting of snow (accumulated in the rain gage) during warm periods and do NOT represent actual precipitation. Precipitation totals during freezing periods may underestimate actual totals because the rain gage funnel may be full of snow (preventing further accumulation) or because snow in the funnel may sublimate instead of melt.
***NOTE: Beginning 22 Apr. 2020, precipitation data are no longer being published at this site. The tall pine trees that surround this site and rain gage have become too tall and were beginning to affect the accuracy of precipitation data this site. Precipitation continue to be collected and published at a nearby site that is 500 ft. NE of this location. These data are available at USGS 473425095052602