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Manual for Abandoned Underground Mine Inventory and Risk Assessment
Section 3: Initial Site Investigation

3.1 GENERAL DISCUSSION:

The Initial Site Investigation fulfills several purposes in the overall inventory and risk assessment process. First, it familiarizes District personnel with inventory site locations. Second, it provides field verification of site characteristics and conditions. Third, it produces a permanent record of site characteristics and conditions which will be utilized for Initial and Detailed Site Evaluation. Last, it may produce field information which could ultimately result in sites being added to or eliminated from the initial inventory of sites.

3.2 AVAILABLE INFORMATION:

The Initial Site Investigation process is performed by utilizing two forms of information. The first form of information is the Initial Site Listing as described in Section 2. The other form of available information is obtained from outside sources and ODOT records .

3.2.1 Initial Site Listing: The initial inventory site listing is the end product of the initial informational review as described in Section 2.

3.2.2 Available Information:Information in addition to that recovered during the development of the initial site listing should be obtained. Sources for this information include: 1)) the Ohio Department of Natural Resources (ODNR), Division of Geological Survey (DGS); 2) the ODNR, Division of Mines and Reclamation ( DMR); 3) the U. S. Department of Interior (USDI.),Office of Surface Mining (OSM); 4) the Ohio Mine Subsidence Insurance Underwriting Association (OMSIUA), and; 5) ODOT.

3.2.2.1 Individual Mine Maps: The first step in the Initial Site Investigation process is to obtain copies of maps for all the individual abandoned underground mines for roadway locations on the established site listing. Individual mine maps are available through ODNR, DGS. They are ordered by the county-number designation displayed on the Abandoned Underground Mine Map Series. A sample copy of one of these individual mine maps is provided as Figure 3.1. The ODNR, DGS "data form" associated with each individual mine map should also be obtained and reviewed. A sample copy of one of these forms is provided as Figure 3.2.

Figure 3.1 Sample Copy of a ODNR, DGS Individual Mine Map

Figure 3.1: Sample Copy of a ODNR, DGS Individual Mine Map

Figure 3.2 Sample Copy of a completed ODNR, DGS Mine Map Data Sheet

Figure 3.2: Sample Copy of a ODNR, DGS Mine Map Data Sheet

These maps, along with all corresponding roadway drawings, should be reviewed for each site. In cases where mine maps and roadway drawings do exist, a preliminary composite plan view of the roadway drawings and mine map(s) should be manually compiled. This information should then be reviewed in preparation for individual site visits.

3.2.2.2 Other ODNR, DGS Information : Other forms of ODNR, DGS information which should be reviewed at this time include: measured geologic sections and geologic structure maps.

3.2.2.3 ODNR, DMR Information: ODNR, DMR historic information regarding subsidence events should be reviewed for events near individual roadway sites.

3.2.2.4 USDI, OSM Information: OSM historic information regarding subsidence events should be reviewed for events near individual roadway sites.

3.2.2.5 OMSIUA Information: OMSIUA historic information regarding subsidence events should be reviewed for events near individual roadway sites.

3.2.2.6 ODOT Information: Roadway and right of way plans, subsurface investigations, centerline survey plat, and county maintenance records should be reviewed.

3.3 INDIVIDUAL SITE VISITS:

The next step in the Initial Site Investigation is to perform individual site visits. These site visits will serve two purposes. The primary purpose is to gather the necessary field data for the site. The secondary purpose is to eliminate sites from the initial site listing if they can be documented to have no potential for a current or future threat to the safety of the traveling public.

3.3.1 Priority Order for Site Visits: These visits shall be conducted on sites in the following priority order of classification of roadway: 1) Interstate; 2) NHS other than Interstate; 3) Arterial, and; 4) Collector.

3.3.2 Preparation for Individual Site Visits: Prior to traveling to the field to conduct an individual site visit, the coordinating District engineer should prepare for this work as outlined on the Pre-Inspection Checklist (Figure 3.3). This form outlines the information which should be office reviewed, the composite overlay plan view of the abandoned underground mine maps over the roadway , notification of the County Manager, and suggested equipment and field gear.

Ohio Department of Transportation
Abandoned Underground Mine Inventory and Risk Assessment

Pre-Inspection Checklist

A. Review Existing Information

1) Abandoned Underground Mine Map Series (U.S.G.S. Based) - Obtain from ODNR. DGS and review.

2) Individual Underground Mine Abandonment Map and associated Data Form from ODNR, DGS - Obtain and Review

3) Roadway and Right of Way Plans - Review

4) Subsurface Investigation

5 Centerline Survey Plat - to help locate mine map (section lines, property lines, etc.)

6) ODNR Historic Information Regarding Subsidence Events - review for events near site

7) OSM Historic Information Regarding Subsidence Events - review for events near site

8) OMSIUA Historic Information Regarding Subsidence Events - review for events near site

9) Abandoned Underground Mine Inventory Field Data Sheets From Counties - review for reports near site

10) County Maintenance Records - review for unusual grade and drainage conditions/maintenance near site

11) Measured Geologic Sections - Obtain from ODNR, DGS and Review

12) Geologic Structure Maps - Obtain from ODNR, DGS and Review

B. Compile Overlay:

1) Scale Adjustment - use plan scale and modify mine map (if necessary) to fit

2) Manually produce composite plan view by overlaying mine map on roadway drawings.

Figure 3.3: Pre-Inspection Checklist Form
Page 1 of 2

C. Notify County Manager:

1) Inform of intent to visit site and invite to participate in site visit

2) Ask about any known records of unusual maintenance or construction at site.

D. Equipment:

shovel permanent marker DMI equipment

tape hammer measuring wheel

camera rock hammer climbing rope

notebook - with grid paper machete binoculars for sketching

locking hand level folding rule clipboard

altimeter (+/- 5 ft.) level rod, telescoping calculator

soil probe sounding rope (cord with scale weight)

mirror hiking compass straight edge

flashlight spray paint protractor

survey lath safety strobe light for vehicle

handheld GPS unit

Figure 3.3: Pre-Inspection Checklist Form
Page 2 of 2

3.3.3 Collection of Required Field Data: The goal for the field site visit is to collect the required field observational information which will be necessary to complete an Initial Site Evaluation and Detailed Site Evaluation. Most ODNR, DMR, Abandoned Mine Land (AML) District Project Officers have many years of experience in reviewing underground mine maps and related field conditions in the development of AML projects. They can provide assistance in reviewing and interpreting sites.

County Garage personnel should be canvassed for local knowledge of underground mining information, including past or present roadway construction or maintenance problems. These employees may also know of local private individuals who might have information regarding past underground mining. Local individuals who might be of help may include mine employees (present day and retired), local historians, etc.

3.3.3.1 Field Visit Form: The final product of the individual site visits should be a completed Site Data Form (Figure 3.4). This form establishes a record of all site information needed to complete the evaluation of a given site through Initial and Detailed Site Evaluations. This information will become part of the body of data which will comprise a Geographic Information System (GIS) site attribute file.

3.3.3.1.1 Site Investigations: These investigations should be conducted while accompanied by the County Manager, or their representative, if possible.

3.3.3.1.1.1 Evidence of Past Mining Activities: A number of observable site features may be evidence of past mining activity in the site vicinity. These features include: mine openings, mine-related structures, coal refuse ("gob") piles, abandoned surface ("strip") mining pits, railroad spurs, and surface water, seeps, or springs having an orange color. While conducting the site visit, the coordinating District engineer should contact local individuals previously identified as possible sources of past mining information.

3.3.3.1.1.2 Surface Deformation Features: A number of observable features may be evidence of mine-related surface deformation in the site vicinity. These features include, but are not limited to: crack patterns or dips in the roadway; damaged or displaced drainage structures; effects on bridges, structures, poles, culverts, etc; unusual vegetation; drag patches; dips in guardrail; dips in flowline of ditches; low spots in grade which retain water; ponds (unusual water formations on surface, impoundments); surface topography anomalies; and level of groundwater.

3.3.3.1.2 Recording Information: The third page of the Site Data Form is used for recording needed site information. The more complete this work is performed on-site, the more likely that the needed information will not be lost or go unrecorded. The following is an outline of on-site activities to accomplish:

1) Record Mining and Geologic Information:

  • Mark features with ribbon, paint, etc.
  • Record type and apparent minimum overburden thickness to top of mined interval, if possible. Estimate minimum overburden thickness as one of the following: < 25 feet , 25 to 50 feet , 50 to 100 feet , > 100 feet .
  • Record maximum mined interval (seam(s)) thickness. If outcrop is observable in the site vicinity, estimate its thickness as one of the following: > 6 feet , 3 feet to 6 feet , < 3 feet
  • Record number of subsidences.
  • Record mine opening information:
    • Type(s) and number(s) of opening(s). Types Include: Drift (Horizontal), Slope, or Shaft( Vertical).
    • Mine opening location(s) relative to the roadway.
      1. Between the Two Outer-Most Edge of Shoulders
      2. Less than 50' Feet From Edge of Shoulder
      3. Between 50' and 100' From Edge of Shoulder
      4. Within Sight From Edge of Shoulder
      5. Location not conclusively known
    • Method of mine opening closure, if observable.
      1. No Information
      2. Timber Decking
      3. Uncontrolled Random Backfill
      4. Concrete Cap
      5. Controlled Backfill
    • Type of mine opening cribbing, if observable.
      1. No Information
      2. Timbers
      3. Brick
      4. Concrete
    • Plan area of mine opening(s), if observable and safe to measure. Estimate area of mine opening as one of the following:
      1. Mine opening size unknown
      2. >750 Sq. Ft.
      3. From 500 to 750 Sq. Ft.
      4. From 250 to 500 Sq. Ft.
      5. From 150 to 250 Sq. Ft.
      6. <150 Sq. Ft.
    • Record field observations of any other unique site features and describe the general site setting.
    • Check information recorded against information reported on Field Data Sheet (if any).
    • Record information provided by local contacts (if any).

2) Record Roadway Information:

  • Record structures in the roadway, as a YES/NO record.
    • Then note type and condition of structure(s), including materials used in their construction.
  • Record posted speed limit within site limits.
  • Record type of pavement.Indicate either: 1)continuous reinforced concrete pavement, or: 2) other. In the case of asphalt surface, verify base pavement construction or reconstruction. Determine if rubblized, or broken and seated.
  • Record evidence that the mine is not under the roadway.

3) Sketch Features on Map / Roadway Plans / Back of Site Data Form:

  • Determine site limits, and sketch them on map/plans.
  • Sketch in topographic anomalies.
  • Sketch in all recorded features.
  • Record elevations relative to the roadway.
  • Measure and record dimensions of recorded features.
  • Record bearing between features using a hand-held hiking compass.

4) Take Photographs:

  • Reference the camera angle.
  • Use "Data Back" film, or record and keep notes with film.
  • Photograph multiple angles of significant features.

3.3.3.2 Elimination of Sites: Some sites will be eliminated from further evaluation through the verification that the abandoned underground mine in question in fact does not lie beneath the highway right-of-way. This possibility could result from; 1) field review and concurrence with plan view composites suggesting this situation or 2) the field determination (visual verification) that the abandoned underground mine was excavated and removed from the site location when excavations were performed to construct the roadway. If the latter is the case for a given site, the danger of subsidence has been eliminated in the roadway, but the possibility of dangerous mine openings in cut slopes should be considered. A separate listing of such sites should be compiled.

Ohio Department of Transportation
Abandoned Underground Mine Inventory and Risk Assessment

Site Data Form


C/R/S/ (Mile Marker): ________________________ Field Report / Office Investigation No. ________________________
Site Description: ___________________________________________________________________________________
_________________________________________________________________________________________________
U.S.G.S. Topographic
Quadrangle ODOT No.:______________
O.D.N.R. Abandoned Underground
Mine Series (U.S.G.S.) Map:______________
O.D.N.R.,DGS Individual Abandoned
Underground Mine Map Index No.:______________
(If known.)

Name of Site Evaluator:________________________________________________Evaluation Date:________________

NOTE: Circle applicable items, and provide comments and sketch. Use back of forms or attach additional sheets as required.

  1. Site Investigations

    1. Evidence of Past Mining Activities

      1. Mine Openings

      2. Mine Structures (ruins/foundations of tipples, fanhouses, scalehouses, wash houses,etc.)

      3. Gob Piles

      4. Strip Pits

      5. Railroad Spurs

      6. Orange water/seeps/springs

      7. Contact Local Residents

    2. Surface Deformation Features

      1. Crack Patterns and Dips in Roadway

      2. Damaged or Displaced Drainage Structures

      3. Effects on Bridges, Structures, Poles, Culverts, etc.

      4. Unusual Vegetation

      5. Drag Patches

      6. Dips in Guard Rail

      7. Dips in Flowline of Ditches

      8. Low Spots Holding Water

      9. Ponds (unusual water formations on surface, impoundments)

      10. Surface Topography Anomalies

      11. Level of Groundwater

    Figure 3.4. Page 2 of 4.  Blank sheet with lines

  2. Recording Information

    1. Record Mining and Geologic Information:

      • Mark Features with Ribbon, Paint,

      • Record Type and Apparent Minimum Overburden Thickness to Top of Mined Interval (if visible).
        • Estimate as one of the following:
          < 25'        25' - 50'       50' - 100'       > 100'

      • Record Maximum Mined Interval (seam(s)) Thickness, if outcrop is observable in site vicinity
        >6'        3' - 6'        0' - 3'

      • Record Number of Subsidences

      • Record Mine Opening Information:

        • Type(s) and Number(s) of Mine Opening(s). Types include: Drift (Horizontal), Slope, and Shaft (Vertical)
          Drift (Horizontal)_________Slope_________Shaft (Vertical) _________

        • Mine Opening Location(s) Relative to Roadway:

          Location Not Conclusively Known Between The Two Outer-Most Edge of Shoulders Less Than 50 Feet From Edge of Shoulder Between 50' and 100' From Edge of Shoulder Within Sight From Edge of Shoulder

        • Method of Mine Opening Closure, if Observable.

          No Information Timber Decking Random Backfill Concrete Cap Controlled Backfill

        • Type of Mine Opening Cribbing, if Observable

          No Information Timbers Brick Concrete

        • Plan Area of Mine Opening(s), if observable and safe to measure.

          Size Is Unknown >750 S. F From 500 to 750 S. F. From 250 to 500 S. F. From. 150 to 250 S. F. <150 S. F.
      • Record Field Observations of any other unique site features and describe the general site setting.

      • Check Information Recorded Against Information Reported on Field Data Sheet (if any).

      • Record Information Provided by Local Contacts (if any), including any information about secondary mining or problems reported during mining.

    2. Record Roadway Information:

      • Record Structures in Roadway site? (YES/NO)

        • Note type and condition of structure(s), including materials used in their construction.,

      • Record Posted Speed Limit Within Site Limits

      • Record Type of Pavement . In the case of asphalt surface, verify base pavement construction or reconstruction. Determine if rubblized. Indicate one of the following:

        Continuously Reinforced           Other
      • Record Evidence That The Mine Is Not Under The Roadway

    3. Sketch Features on Map / Roadway Plans/ Back of This Form

      • Determine Site Limits -Sketch on Map /Plans

      • Sketch in Topographic Anomalies

      • Sketch in All Recorded Features

        • Record elevations relative to the roadway
        • Measure and record dimensions of recorded features.
      • Record Bearing Between Features using a hand-held hiking compass

    4. Take Photographs:

      • Reference the Camera Position if Possible,

      • Use "Data Back" Film, or Record and Keep Notes with Film.

      • Photograph Multiple Angles of Significant Features

    Figure 3.4 Page 4.4 Site Data Form. Blank Grid
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Updated: 04/07/2011

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