Chapter 2 - Digging

Table of Contents | Chapter 1 | Chapter 3 | Chapter 4 | Chapter 5

Digging Open an Entrance:

Digging in A Sinkhole Entrance: Probably the most common place for a dig, a sinkhole is depression in the ground where a cave entrance may be formed. The most common problem with sinkhole digs is instability caused by loose soil or rock materials.  Often, sinkholes have been filled by landowners in an attempt to keep livestock or people out of harms way.  In addition to rock, digs in sinkholes often have to deal with the removal of brush, stumps, debris, trash, appliances, barbed wire, fencing, and dead animals.  In steep-sided sinkholes, shoring is often needed to keep the walls stable, and the diggers safe.
Digging in a Fissure Entrance: Fissure digs can be either horizontal or vertical (or slanted) but always involved excavting a filled "crack" that leads to bigger cave passage.  These types of digs may occur on cliff face, or at the bottom of a sinkhole.  Stability is usually less of a problem because the walls are bedrock, but loose rocks or unstable slabs can still cuase problems.  Shoring is rarely needed.
Digging Through Solid Earth: One of the more foolhardy tasks unless you know a cave exists under a particular spot, this is the most labor (or energy) intensive type of digging.  Sometimes a small, steep collapse or "dimple" may tempt some energetic and enthusiastic cavers to dig through solid earth. Several large-scale digs through solid earth and rock have been performed in recent years to excavate a safer or more convenient entrance to known large cave systems.  Shoring and/or culvert installation is almost always required in this type of dig.
Digging in a Stream/Water:  In places where water enters or exits the ground, the potential for a cave exists.  Often digging in these locations can yield significant dry cave passage, but can be cold, tedious, and uncomfortable for the diggers.  Shoring is sometimes necessary, and a wetsuit is usually mandatory for the diggers.

Serious Digging: 20 feet through earth, then 60 feet through solid rock, into the top of an 80 foot tall passage in western Virginia. 

Similar digs have been performed in Missouri and other states.  The used of heavy equipment, air-powered tools, and the use of chemical persuasion are usually necessary.  You better have a good reason (i.e. big cave) and a full wallet to undertake one of these projects.


Digging Open Cave Passage (inside the cave):

Digging in Cobble Passage:
Digging in Mud Passage:
Digging in Rocks or Breakdown:
Digging through Rock - unless the rock is so rotten or weather that it can be excavated normally, one of the "rock shaving" methods listed below is usually required to enlarge a cave passage in rock.  In some cases where the rock is highly fractured or jointed, the rock can be pulled apart in small pieced with the use of a hammer/chisel or pry bar.  


Rock Shaving Techniques:

The methods used to enlarge bedrock passage have changed in recent years.  Most cave passage that needs to be enlarged only needs marginal modification to the passage of a normal size caver.  These tight spots or constrictions required the use of localized force (directed energy) to remove some of the offending limestone.  Some of the most commonly used methods are listed below.

Manual Methods: hammer, chisel  
Mechanically Assisted Methods:  feathers and wedges, pry bars  
Powered Mechanical Methods: hammer drill, power chisel      
Micro-Burst Method: Hilti caps, small caliber shells  
Macro-Burst Methods: larger stuff  


Mass Removal Tools and Techniques:

Tools - Shovels, Hoes, Sledgehammers, Pry Bars  
Buckets and Sacks - good for vertical digs  
Sleds and Sliders - good for horizontal digs
Mechanical Systems - pulleys, cranes, haul systems    
Powered Systems - backhoes, tractors  
Alternatives ???