Code of Maine Rules › 06 - DEPARTMENT OF ENVIRONMENTAL PROTECTION › 096 - DEPARTMENT OF ENVIRONMENTAL PROTECTION - GENERAL › Chapter 500 - STORMWATER MANAGEMENT › Section 096-500-3 - Definitions

Current through 2024-29, July 17, 2024
The following terms have the following meanings as used in
				  this Chapter and 06-096 CMR Chapter 502 (Direct Watersheds of Lakes Most at
				  Risk from New Development and Urban Impaired Streams), unless the context
				  otherwise indicates.
A.
Certified Professional in Erosion and Sedimentation Control (CPESC).
				"
Certified Professional in Erosion and Sedimentation Control (CPESC)"
				means a professional certified by Enviro-Cert International in erosion and
				sediment control practices.
B.
Compensation fee utilization plan.
"Compensation fee utilization
				plan" means a plan that specifies how funds received as a compensation fee
				payment will be allocated to reduce the impact of stormwater pollution to an
				impaired water resource.
C.
Detention basin.
"Detention basin" means a basin designed and constructed
				to provide temporary storage of runoff to control stormwater outflow from the
				site and manage peak flows downstream and to provide gravity settling of
				pollutants.
D.
Developed
				area.
"Developed area" means an impervious area, landscaped area, or
				unrevegetated area. Developed area includes all disturbed areas except an area
				that is returned to a condition that existed prior to the disturbance and is
				revegetated within one calendar year of being disturbed, provided the area is
				not mowed more than twice per year.
E.
Direct watershed of a waterbody or
				wetland.
"Direct watershed of a waterbody or wetland" means the land
				area that drains via overland flow, drainageways, waterbodies, or wetlands to a
				given waterbody or wetland without first passing through a lake or
				pond.
F.
Disturbed
				area.
"Disturbed area" means all land areas that are stripped, graded,
				grubbed, filled, bulldozed or excavated at any time during the site preparation
				or removal of vegetation for, or construction of, a project. "Disturbed area"
				does not include maintenance. A land area on which the cutting of trees,
				without grubbing, stump removal, disturbance or exposure of soil has taken
				place is not considered a "disturbed area".
G.
Drainageway.
"Drainageway"
				means a natural or man-made channel or course to or from which surface
				discharge of water may occur. Drainageways include, but are not limited to
				streams (whether intermittent or perennial), swales, ditches, pipes, culverts,
				and wetlands with localized discharge of water.
H.
Erosion and sedimentation control
				best management practices (erosion control BMPs).
"Erosion and
				sedimentation control best management practices (erosion control BMPs)" means
				methods, techniques, designs, practices, and other means to control erosion and
				sedimentation.
NOTE
: The Department has prepared protocols for
				  the control of erosion and sedimentation. See "Maine Erosion and Sediment
				  Control BMPs Maine Department of Environmental Protection."
I.
Erosion control mix.
"Erosion
				control mix" means a mulch that consists primarily of organic material such as
				shredded bark, stump grindings, composted bark, or fragmented wood generated as
				a by-product from log handling at wood mills. It includes a well-graded mixture
				of particle sizes with a mineral content that is less than 20% by weight, and
				is free from construction debris, refuse, and contaminants.
J.
High-use parking
				lot
."High-use parking lot" means a commercial or other parking lot,
				where parking is used most days and each visit is typically for aduration of
				less than two consecutive hours, such as a parking lot serving a convenience
				store, high-turnover restaurant, shopping center, or supermarket.
K.
Hydrologic Soil
				Groups.
Hydrologic Soil Groups are a ranking of soil types for runoff
				potential adopted by the Natural Resources Conservation Service of the U.S.
				Department of Agriculture used in estimating direct runoff. The four hydrologic
				groups are A, B, C, or D, where group A generally has the lowest runoff
				potential and group D has the highest.
L.
Impervious area.
"Impervious
				area" means the total area of a parcel covered with a low-permeability material
				that is highly resistant to infiltration by water, such as asphalt, concrete,
				or rooftop, and areas such as gravel roads and unpaved parking areas that will
				be compacted through design or use to reduce their permeability. Common
				impervious areas include, but are not limited to, rooftops, walkways, patios,
				driveways, parking lots or storage areas, concrete or asphalt paving, gravel
				roads, packed earthen materials, and macadam or other surfaces which similarly
				impede the natural infiltration of stormwater. Pervious pavement, pervious
				pavers, pervious concrete and underdrained artificial turf fields are all
				considered impervious. For the purpose of determining jurisdictional
				thresholds, the Department may, depending on the design, consider such
				facilities to provide alternative treatment as described in Section 4(B)(3)(e)
				of this Chapter.
M.
Infiltration.
"Infiltration" means the process by which runoff percolates
				through the unsaturated overburden and fractured bedrock to the water table,
				including any process specifically used to meet all or part of the stormwater
				standards of this Chapter by actively directing all or part of the stormwater
				into the soil. For the purposes of this Chapter, infiltration does not include:
(1) Incidental wetting of soil in ditches,
				detention basins or the equivalent;
(2) Wetting of underdrained basins, dry
				swales, or similar filtration systems that do not subsequently discharge to
				groundwater; or
(3) Wetting of
				buffers meeting Department requirements for use as stormwater control.
Discharge of runoff to areas of the site where the water will
				  collect and percolate into the ground is considered infiltration if the volume,
				  rate, or quality of the discharge does not meet Department standards for use of
				  the area as a stormwater treatment buffer. Underdrained swales, underdrained
				  ponds, and similar practices that discharge to surface waters or to buffer
				  strips meeting Department requirements in Appendix F of this Chapter for
				  stormwater buffers are not considered infiltration systems, although these may
				  be used to treat runoff prior to discharge to an infiltration area.