Wyoming Administrative Code
Agency 020 - Environmental Quality, Dept. of
Sub-Agency 0011 - Water Quality
Chapter 24 - Class VI Injection Wells and Facilities Underground Injection Control Program
Appendix A - Risk Activity Table

Major Risk (Feature, Event, or Process)

1

Mineral Rights Infringement (Trespass)

1.1

Leakage migrates into mineral zone or hydraulic front impacts recoverable mineral zone; causes may include plume migration different than modeled.

1.2

Post injection discovery of recoverable minerals.

1.3

New technology (or economic conditions) enables recovery of previously uneconomically recoverable minerals.

1.4

Act of God (e.g. seismic event).

1.5

Formation fluid impact due to CO2 injection.

1.6

Address also contributing causes 3.1, 3.2, 3.3, 3.5, 4.3, and 4.4

2

Water Quality Contamination

2.1

Leakage of CO2 outside permitted area.

2.2

Leakage of drilling fluid contaminates potable water aquifer.

2.3

Rock/acid water (i.e. geochemistry) interaction contaminates potable water by carryover of dissolved contaminants.

2.4

Act of God (e.g. seismic event).

2.5

Formation fluid impact due to CO2 injection.

2.6

See also contributing causes 3.1, 3.2, 3.3, 3.5, 4.3, and 4.4

3

Single Large Volume CO2 Release to the Surface - Asphyxiation/Health/Ecological

3.1

Over pressurization (i.e. induced).

3.2

Caprock/reservoir failure.

3.3

Well blowout (e.g. at surface or bore failure below ground), includes monitoring wells - Causes could include seal failure (e.g. well, drilling or injection equipment).

3.4

Major mechanical failure of distribution system or storage facilities above ground or below ground (i.e. near the surface).

3.5

Orphan well failure (e.g. well not identified prior to injection).

3.6

Sabotage/Terrorist attack (e.g. on surface infrastructure).

3.7

Act of God (e.g. major seismic event)

4

Low Level CO2 Release to Surface - Ecological damage due to low-level releases; potential asphyxiation of human or ecological receptors

4.1

Over pressurization (i.e. induced).

4.2

Caprock/reservoir failure (e.g. Plume migrates along fault line/fissure to surface).

4.3

Incomplete geological seal (e.g. inaccurate characterization of sub-surface geology).

4.4

Well seal failure (e.g. well, drilling or injection equipment) including monitor wells

4.5

Mechanical failure of distribution system or storage facilities above or below ground (e.g. near surface).

4.6

Orphan wells (e.g. well not identified prior to injection).

4.7

Induced seismicity leading to leakage.

4.8

Act of God (e.g. seismic event).

Major Risk (Feature, Event, or Process)

5

Storage Rights Infringement (CO2 or other entrained contaminant gases) - Form of Mineral Rights Infringement

5.1

Leakage migrates into adjacent pore space; causes may include plume migrates faster than modeled.

5.2

Post injection decision (e.g. due to new technology or changed economic conditions) to store gas in adjacent pore space.

5.3

Acts of God affecting storage capacity of pore space.

5.4

Formation fluid impact due to CO2 injection.

5.5

Will also require primary contributing causes 3.1, 3.2, 3.3, 3.5, 4.3, and 4.4

6

Modified Surface Topography (subsidence or uplift) Resulting in Property/Infrastructure Damage

6.1

Induced Seismicity - Pressure from geochemistry induced reactivation of historic fault or dissolution of material caused by subsidence.

6.2

Formation fluid impact due to CO2 injection.

7

Entrained Contaminant (Non-CO2) Releases

7.1

Change in CO2 composition/properties (e.g. concentration of contaminate in CO2 supply increases).

7.2

Microbial activity initiated by injection process or composition.

Will also require primary contributing causes 3.1, 3.2, 3.3, 3.5, 4.3, and 4.4

8

Accidents/Unplanned Events (Typical Insurable Events)

8.1

Surface infrastructure damage

8.2

Saline water releases from surface storage impoundment.