The classification of a particular well is determined by the
department based upon the following categories and discharge characteristics.
The applicable regulatory category and rule section for each well type is
indicated in parentheses.
A.
Class I wells. Wells that discharge fluids under the following
circumstances:
(1) Wells used by generators
of hazardous waste or owners or operators of hazardous waste management
facilities to discharge hazardous waste beneath the lowermost formation
containing groundwater;
(2) Other
industrial and municipal disposal wells that discharge fluids beneath the
lowermost formation containing groundwater; or
(3) Radioactive waste disposal wells that
discharge fluids below the lowermost formation containing groundwater.
(Note: Prohibited, see § 3C)
B.
Class II wells.
Wells that discharge fluids:
(1) That are
brought to the surface in connection with natural gas storage operations, or
conventional oil or natural gas production and may be commingled with
wastewaters from gas plants that are an integral part of production operations,
unless those waters are classified as a hazardous waste at the time of
discharge;
(2) For enhanced
recovery of oil or natural gas; or
(3) For storage of hydrocarbons that are
liquid at standard temperature and pressure.
(Note: Prohibited, see § 3C)
C.
Class III wells.
Wells that discharge fluids for extraction of minerals including:
(1) Wells used for the mining of sulfur by
the Frasch process;
(2) Wells used
for in situ production of uranium or other metals, limited to the in-situ
production from ore bodies which have not been conventionally mined;
or
(3) Wells used for solution
mining of salts or potash.
(Note: Prohibited, see § 3C)
NOTE: Solution mining of conventional mines, such as stopes
leaching, is included in Class V. See Section 2(E)(9)(b). Stopes leaching is
not considered in-situ leaching, but is considered mining for the purposes of
06-096 Chapter 200.
D.
Class IV wells. Wells that
discharge fluids under the following circumstances:
(1) Wells used by generators of hazardous
waste or of radioactive waste, by owners or operators of hazardous waste
management facilities, or by owners or operators of radioactive waste disposal
sites to dispose of hazardous waste or radioactive waste into or above a
formation which contains groundwater (Note: Prohibited, see § 3D
);
(2) Wells used by generators of
hazardous waste or owners or operators of hazardous waste management facilities
to dispose of hazardous waste that cannot otherwise be classified under Section
2(A)(1) or Section 2(D)(1) (Note: Prohibited, see § 3D); or
NOTE: Subsurface disposal of drinking water filter backwash
containing radionuclides below concentrations determined to be radioactive
waste is included in Class V. See Sections 2(E)(2)(d) and 2(E)(11)(c).
(3) Wells used to discharge
solutions to remediate contamination in situ or to discharge contaminated
groundwater that has been treated and is being discharged into the same
formation from which it was drawn, pursuant to provisions for cleanup of
releases under CERCLA, RCRA or 38 M.R.S.A. Chapters 11-A, 11-B, and 13-B.
(Note: Authorized by meeting conditions of LBR, see § 5A)
E.
Class V wells.
Wells not included in Class I, II, III, IV or VI. Class V wells are
divided into the following subclasses.
(1)
Motor vehicle waste disposal wells, which consists of wells that receive fluids
discharged from areas in which vehicular repair or maintenance activities
occur, including, but not limited to, activities performed at such businesses
as automotive and auto body repair shops; new and used car and truck
dealerships; aircraft, outboard engine, snowmobile, lawnmower, and ATV sales
and repair shops; specialty repair shops; and any person that does gasoline- or
diesel-engine repair work, whether those services are offered to the public or
not. (Note: Prohibited, see § 3E)
(2) Industrial wells that receive discharges
of non-domestic wastewater. Industrial wells include, but are not limited to:
(a) Wells that receive wastewater from
automatic, tunnel, roll-over, and hand-held car washes;
(b) Wells that receive wastewater from egg
washing facilities;
(c) Wells that
receive wastewater from commercial fish or shellfish processing facilities
excluding home occupation fish or shellfish processing facilities;
(d) Wells that receive public drinking water
treatment plant filter backwash water, except filter backwash from surface
water sources with no chemical additions; and except as provided in Section
2(E)(11)(c);
(e) Wells that receive
wastewater from septage storage and dewatering facilities and Type IC, Type II,
and Type III residual processing facilities;
(f) Wells that receive water from secondary
containment dikes and berms at Aboveground Storage Tank facilities that has the
potential to contain concentrations of oils and hazardous materials (OHM). This
includes wells that receive stormwater from catch basins within loading and
off-loading racks at bulk oil facilities, gas stations, or other facilities
that have the potential to receive OHM spilled during loading and off-loading
activities; or
NOTE: For information on residuals and processing facilities,
see 06-096 CMR 400, 409, 419 and 420. In general, Type IC residuals come from a
known source that does not contain hazardous substances and have a carbon to
nitrogen ratio of 15:1 or less. Type IC residuals include mussels, shrimp,
fish, crab, and lobster wastes; poultry carcasses; and hen manure. Type II
residuals come from a known source that does not contain hazardous substances
but may contain human pathogens. Type II residuals include sewage sludge,
dewatered septage and disposable diapers. Type III residuals may contain
hazardous substances. Type III residuals include non source-separated
residential wastes and petroleum contaminated soils.
(g) Wells that receive wastewater from any
other commercial, industrial or manufacturing processes that contains
constituents unlike that or of significantly higher strength than that of
domestic wastewater.
(Note: WDL required, see § 4A)
(3) Large-capacity cesspools which
consist of those that receive solely domestic wastewater and have the capacity
to serve 20 or more persons per day or dispose of 2,000 gallons or more of
domestic wastewater per day. This definition includes multiple-dwelling,
community or regional cesspools of all sizes but does not apply to
single-family cesspools or to non-residential cesspools that serve fewer than
20 persons per day and dispose of less than 2,000 gallons of domestic
wastewater per day. (Note: Prohibited, see § 3E)
(4) Stormwater drainage wells that are used
for the disposal of rain water and melted snow. (Note: Authorized by meeting
conditions of LBR, see § 5B)
(5) Other drainage wells that are used to
drain surface and subsurface fluids other than stormwater. These wells include,
but are not limited to:
(a) Agricultural
drainage wells that receive irrigation runoff;
(b) Construction dewatering wells that are
used to lower the water table and keep foundation excavation pits dry;
or
(c) Swimming pool drainage wells
that receive chlorinated water from swimming pools and hot tubs, including
pass-through analyzer water from public drinking water treatment plants.
(Note: Authorized by meeting conditions of LBR, see § 5B
)
(6) Beneficial
use wells that receive fluids to improve either flow of aquifers or some other
groundwater management benefit. Beneficial use wells receiving stormwater
runoff are regulated as stormwater drainage wells. Beneficial use wells
include, but are not limited to:
(a) Aquifer
recharge wells used to replenish the water in an aquifer;
(b) Aquifer storage and recovery wells used
to place excess water in the subsurface during periods of high flow and then
withdraw the water later when it is needed;
(c) Subsidence control wells used to inject
fluids to prevent the land surface from sinking or settling; or
(d) Wells that inject water to control the
intrusion of salt water in coastal areas into freshwater aquifers.
(Note: Authorized by meeting conditions of LBR, see § 5B
)
(7) Fluid
return wells that receive discharges of water that has been used for heating or
cooling a heat pump or water extracted for the recovery of geothermal energy
for heating, aquaculture, and the production of electrical power. (Note:
Authorized by meeting conditions of LBR, see § 5B)
(8) Non-contact cooling water wells that
receive discharges of non-contact cooling water that contains no additives and
has not been chemically altered. Wells that inject contact cooling water or
non-contact cooling water that contains additives, such as corrosion inhibitors
or biocides, or is contaminated compared to the original source water are
considered industrial wells, as defined in Section 2(E)(2). (Note: Authorized
by meeting conditions of LBR, see § 5B)
(9) Mining and recovery wells that receive
discharges of fluids used in the production of energy or minerals; or for
subsidence prevention, disposing of wastes and fire control in mining
operations. These include, but are not limited to:
(a) Sand backfill and other backfill wells
used to discharge a mixture of water and sand, mill tailings or other solids
into mined out portions of subsurface mines, whether what is discharged is a
radioactive waste or not;
(b) Wells
used for solution mining of conventional mines such as stopes
leaching;
(c) Wells used to
discharge spent brine into the same formation from which it was withdrawn after
extraction of halogens or their salts; or
(d) Wells used for in situ recovery of
lignite, coal, tar sands, and oil shale.
(Note: WDL required, see § 4A)
(10) Experimental technology wells
used as an integral part of an unproven subsurface injection technology other
than waste disposal. (Note: WDL required, see § 4A)
(11) Other injection wells that receive
non-hazardous, industrial and commercial wastes which have constituents similar
in type and concentration to domestic wastewater. Other injection wells
include, but are not limited to, wells that receive:
(a) Snowmelt from cars, trucks, snowmobiles
and other motor vehicles;
(b)
Filter backwash from swimming pools and hot tubs;
(c) Drinking water system filter backwash
including those containing radionuclides provided the radioactive material is
below concentrations considered to be radioactive waste as listed in 10 CFR
Part 20, Appendix B, Table II, Column 2, and provided the applicant can
demonstrate that all other pollutants are de
minimis;
(d) Boiler
blowdown, provided that the applicant has demonstrated that no other acceptable
disposal option exists.
(Note: Authorized by meeting conditions of LBR, see § 5B
)
NOTE: Some Class V wells located at single-family homes are
exempt from some requirements under this rule. Please see Section 5(D) for more
information.
F.
Class VI wells. Class VI
wells include all wells designed, installed, and operated in conformance with
the "Maine Subsurface Waste Water Disposal Rules," 10-144 CMR 241, and used for
the disposal of domestic wastewater or other wastewater from commercial,
industrial or residential sources that is of similar quality (constituents and
strength) to that of domestic wastewater. Class VI wells include, but are not
limited to:
(1) Single-family, other
residential and non-residential septic systems including, but not limited to,
large-capacity septic systems that have the capacity to serve 20 or more
persons per day and engineered disposal systems with design flows in excess of
2,000 gallons per day;
(2)
Single-family cesspools used solely for the disposal of domestic waste and
non-residential cesspools provided their layout and use complied with the
subsurface waste water or plumbing code provisions prevailing when the system
was first put into use; they are used solely for the disposal of domestic
waste; and they have the capacity to serve fewer than 20 persons per day and
dispose of less than 2,000 gallons per day;
(3) Wells receiving wastewater from home
occupation fish or shellfish processing;
(4) Wells receiving wastewater from
laundromats where no on-site dry cleaning is performed and where no organic
solvents are used for laundering;
(5) Wells receiving wastewater from funeral
homes; or
(6) Wells receiving
wastewater from hospitals, restaurants, nursing homes, schools, hotels, motels,
dental and veterinary facilities and other commercial and industrial
establishments provided the wastewater does not contain constituents unlike
that of or in significantly higher strength than found normally in domestic
wastewater.
(Note: Covered under State Plumbing Code, see §6
)
