Table Name | Field Name | Begin Column | Definition | Valid Values | Descriptions
carlpits.dbf |  |  |  |  |
| PIT_Q_ID |  | Number, 9,0 | Ex: 1,2,3,4,5,6,7.... 341, 342, 343, 344 | Aggregate pit unique ID
| Source |  | Text, 30 | See Below | Construction aggregate pit data source compiled from or observed (ex: topographic map- found on the topographic map). Where multiple records existed for a single gravel pit, data points were removed based on a constructed hierarchy of source information. The following sources of information are listed according to rank.
|  |  |  | ASIS | Minnesota Department of Transportation database called Aggregate Source Information Systems. If the location did intersect a gravel pit, the locations were interpreted off of existing gravel pit sheets to relocate the mines to as specified on the sheet. This was ranked highest because of associated quality and texture data. Some locations were modified to better correlate to present gravel pit boundaries and on top of USGS 7.5 Minute Topographic Map symbols.
|  |  |  | Air Photo | Gravel mines were also located and some attributes were interpreted with air photography. These pits were ranked last because they were remotely interpreted.
|  |  |  | Field Work | These pits were located while in the field. These pits were ranked third highest due to the fact they were directly observed for quality, texture, and locational accuracy.
|  |  |  | Soil Survey | The records for these pits are from the Soil Survey Geographic Database (SSURGO) for Carlton County. The dataset was downloaded in January 2008 and is current as of November 2006. These pits were ranked fourth highest.
|  |  |  | Topographic Map | These gravel pits are located from USGS 7.5 minute quadrangles. This was ranked second highest because of the widespread use of the maps. Where field checked, some of these pit types were changed from gravel to clay, borrow or sand pits to reflect the material excavated.
| Type |  | Text, 30 | See Below | The type of pit observed
|  |  |  | Gravel Pit | Gravel Pit
|  |  |  | Sand Pit | Sand Pit
|  |  |  | Borrow Pit | Borrow Pit- is defined not by use but by material. If a pit contains significant clay and silt material, it was classified as borrow.
|  |  |  | Clay Pit | Clay Pit contains homogenous clay material of a quality used for creating bricks.
| Asis_numbr |  | Text, 8, 0 | Ex: 09002, 09019,, 09115, | Aggregate Source Information System Number (MN/DOT Database). An empty field means that it does not have an ASIS number. Use this field to join with carldotqual.dbf for the pits that list the Source as “ASIS”
| Size |  | Text, 8 | See Below | Refers to the relative size of the pit.
|  |  |  | Small | Small pits are generally less than five acres. These pits are usually used by private landowners or for small jobs.
|  |  |  | Medium | Between 5 and 15 acres in size. These pits are used by landowners and for small construction jobs, They are generally used for short periods of time by contractors.
|  |  |  | Large | These pits are generally greater than 15 acres and are typically used by commercial aggregate operators.
| Thickness |  | Text, 15 | Ex: +10, ~20, +25, 10, 25 | The thickness of the deposit expressed in combination with a modifier.
| Thick_mod |  | Text, 1 | Ex: +,- | Modifiers to express numeric approximations observed for deposit thickness: + greater than - to, as in 10-20
| Thick_min |  | Number, 4 | Ex: 5, 10, 15…-999 | Gives the minimum value for thickness. (-999 is a null value)
| Thick_max |  | Number, 4 | Ex: 5, 10, 15…-999 | Gives the maximum value for thickness. (-999 is a null value)
| Overburden |  | Text, 15 | Ex: +10, ~20, +25, 10, 25 | Expresses overburden thickness by possibly using one or both the modifier and value.
| Ob_mod |  | Text, 1 | Ex: ~, -, + | Modifiers to express numeric approximations for the overburden thickness at a gravel pit. ~ approximate - to, as in 10-20 + greater than
| Ob_min |  | Number, 4 | Ex: 5, 10. 15…-999 | Gives the minimum value for overburden thickness. (-999 is a null value).
| Ob_max |  | Number, 4 | Ex: 5, 10. 15…-999 | Gives the maximum value for overburden thickness. (-999 is a null value).
| Watertable |  | Text, 15 | Ex: +10, ~20, +25, 10, 25 | The depth of the water table expressed in combination with a modifier.
| Wattabmod |  | Text, 1 | Ex: ~, -, + | Modifiers to express numeric approximations for the depth to the water table: ~ approximate - to, as in 10-20 + greater than
| Wattabmin |  | Number, 4 | Ex: 5, 10. 15…-999 | Describes the minimum depth to the water table within a pit or quarry. If 20 feet of gravel was exposed and there was no water table encountered, then +20 were used. (-999 is a null value)
| Wattabmax |  | Number, 4 | Ex: 5, 10. 15…-999 | Describes the maximum depth to the water table within a pit or quarry. If 20 feet of gravel was exposed and there was no water table encountered, then +20 were used. (-999 is a null value)
| Status_1 |  | Text, 20 | See Below | Refers to the status of the pit at the time of mapping.
|  |  |  | Active | Active indicates that the pit is either being actively mined or used for other mining related usage like stockpiling material.
|  |  |  | Inactive | Refers to a pit that was not immediately active when documented or may appear to have been inactive for some time.
|  |  |  | Reclaimed | The pit has been passively or actively reclaimed. Status_2 further describes the type of reclamation.
|  |  |  | Partially Reclaimed | Part of the pit has been passively or actively reclaimed. Status_2 further describes the type of reclamation.
| Status_2 |  | Text, 50 | See Below | Associated with the field Status_1. This field further explains the condition of a partially or fully reclaimed gravel pit. The status could be a combination of more than one use.
|  |  |  | Active | Specifies that mine is an active aggregate producing mine.
|  |  |  | Agriculture | Mine has been reclaimed into an agricultural use.
|  |  |  | ATV Trail | Mine is being used as ATV recreation area.
|  |  |  | Commercial | Mine has been reclaimed into an commercial development like a strip mall, a store, etc.
|  |  |  | Grass | Mine has been re-vegetated with grass.
|  |  |  | Inactive | Mine is not presently active at time of assessment.
|  |  |  | Industrial | Mine has been reclaimed into a refinery, substation, highway or other industrial application.
|  |  |  | Naturally Vegetated | Mine has been passively, or naturally re-vegetated over time.
|  |  |  | Partially Vegetated | Mine has been partially re-vegetated and is partially unreclaimed.
|  |  |  | Pond | Mining was likely below the water table and created a pond.
|  |  |  | Recreation area | Mine has been reclaimed into a public recreation area.
|  |  |  | Residential | Mine has been reclaimed into residential development.
|  |  |  | Sloped | Part or all of mine has been actively reclaimed and mine walls have been sloped.
|  |  |  | Storage | Mine has been reclaimed into a storage area including a timber storage site or a mini storage facility.
|  |  |  | Trees | Mine has been revegetated with trees and shrubs.
|  |  |  | Wetland | Part or all of mine is covered by a wetland.
| Dom_litho |  | Text, 30 | See Below | Dominant lithology of the pit.
|  |  |  | Superior Lobe/Des Moines Lobe | Intermixed sediments from the Superior Lobe glacier and the St. Louis Sublobe of the Des Moines Lobe glacier. Sand and gravel associated with the St. Louis Sublobe glacier can contain deleterious rocks (like shale, iron oxides, and soft limestones) that can degrade the quality of the deposit. Stratigraphically the St. Louis Sublobe is on top of Superior Lobe sediments.
|  |  |  | Superior Lobe | Superior Lobe is a northeastern sourced glacier flowing from the Lake Superior basin to the southwest. The quality of these deposits tends to be good to very good due to the rock types found within the deposits (basalt, granite, gabbro).
| Dom_text |  | Text, 35 | See Below | The dominant texture of the pit.
|  |  |  | Clay | Very fine-grained minerals which show plasticity depending on water content. Used in the construction of bricks in the Wrenshall area.
|  |  |  | Could not observe | The texture of the pit was undetermined due to lack of access or exposure. In some cases proximal geologic evidence was used to make a textural determination.
|  |  |  | Gravel with Sand | Rock fragments of specific particle size that is larger than 2 mm and less than 63 mm.
|  |  |  | Sand | Indicates the deposit is composed of sand and has a fine texture.
|  |  |  | Sand and Gravel | Indicates the deposit has approximately equal or slightly more sand than gravel by percent weight.
|  |  |  | Sand minor Gravel | Indicates the deposit contains mostly sand with few gravel-sized rocks and has a fine texture.
|  |  |  | Sand with Gravel | Indicates the deposit overall has more sand than gravel by percent weight and has an overall fine texture.
|  |  |  | Till | Heterogeneous deposit possibly consisting of any combination of clay, silt, sand, gravel, cobbles, and boulders. Any granular material is within a clayey or silty matrix.
| Comments |  | Text, 100 | Ex: Very sandy deposit with limited gravel | Geologist comments related to the pit.
| GPQNAME |  | Text, 50 |  | If available, the pit name at the time of mapping.