Governmental Roles and Responsibilities Related to Underground Injection and Induced Seismicity - Induced Seismicity Potential in Energy Technologies - page 103

Operational
requirements

Injection pressure at the wellhead
shall not exceed a maximum which
shall be calculated so as to ensure
that the pressure during injection
does not initiate new fractures or
propagate existing fractures in
the conining zone adjacent to the
USDWs (see 40 CFR 146.23(a)
(1)). Injection between the outermost
casing protecting underground
sources of drinking water and the
well bore shall be prohibited.

No speciic injection requirements
are outlined for Class V wells except
that “injection activity cannot allow
the movement of luid containing
any contaminant into USDWs, if the
presence of that contaminant may
cause a violation of the primary
drinking water standards … or may
otherwise adversely affect the health of
persons” (see 40 CFR 144.82(a)).

Except during stimulation, the owner
or operator must ensure that injection
pressure does not exceed 90 percent of the
fracture pressure of the injection zone(s)
so as to ensure that the injection does not
initiate new fractures or propagate existing
fractures in the injection zone(s) (see 40
CFR 146.88(a)).

Termination
of permits

The Director may terminate a permit
during its term, or deny a permit
renewal application for the following
cause: a determination that the
permitted activity endangers human
health or the environment and can
only be regulated to acceptable levels
by permit modiication or termination
(see 40 CFR 144.40(a)(3)).

The Director may terminate a permit
during its term, or deny a permit
renewal application for the following
cause: a determination that the
permitted activity endangers human
health or the environment and can only
be regulated to acceptable levels by
permit modiication or termination (see
40 CFR 144.40(a)(3)).

The Director may terminate a permit
during its term, or deny a permit renewal
application for the following cause:
a determination that the permitted
activity endangers human health or the
environment and can only be regulated to
acceptable levels by permit modiication or
termination (see 40 CFR 144.40(a)(3)).

a The table provided by EPA describes Class II wells as “injected below the lowermost USDW.” Although this is correct in most cases, injection
below the lowermost USDW is not required for Class II wells, according to UIC regulations.
b Most Class V wells are unsophisticated shallow disposal systems that include storm water drainage wells, cesspools, and septic system leach
ields. Wells used for luid injection in association with the recovery of geothermal resources are included in this class because they are an injec-
tion well “not included in Classes I-IV.”
c A review of geothermal injection wells performed by the EPA in 1999 notes, “The permits [for Class V wells] are issued by state agencies,
US Bureau of Land Management (BLM), and/or the USEPA Regional Ofice, depending on the state and whether the well is located on state,
federal, or private land. In general, the permits are similar to those issued for Class II injection wells” (EPA, 1999).