301 CMR 11.03
Review Thresholds
The review thresholds identify categories of Projects or aspects thereof of a nature, size or
location that are likely, directly or indirectly, to cause Damage to the Environment. Except when
the Secretary requires fail-safe review, the review thresholds determine whether MEPA review
is required. MEPA review is required when one or more review thresholds are met or exceeded
and the subject matter of at least one review threshold is within MEPA jurisdiction. A review
threshold that is met or exceeded specifies whether MEPA review shall consist of an ENF and
a mandatory EIR or of an ENF and other MEPA review if the Secretary so requires. The subject
matter of a review threshold is within MEPA jurisdiction when there is full-scope jurisdiction
(i.e., the Project is undertaken by an Agency or seeks the provision of Financial Assistance) or
when the subject matter of the review threshold is conceptually or physically related to the
subject matter of one or more required Permits (provided that the review thresholds for Land and
Areas of Critical Environmental Concern shall be considered to be related to the subject matter
of any required Permit) or the area subject to a Land Transfer. The review thresholds do not
apply to: a lawfully existing structure, facility or activity; Routine Maintenance; a Replacement
Project; or a Project that is consistent with a Special Review Procedure review document, or
other plan or document that has been prepared with the express purpose of assessing the potential
environmental impacts from future Projects, has been reviewed as such in accordance with
MEPA and 301 CMR 11.00, and has been allowed or approved by any Participating Agency,
unless the filing of an ENF and an EIR was required by a decision of the Secretary on any such
review document, plan or document. The review thresholds are the following:
(1) Land.
(a) ENF and Mandatory EIR.
1. Direct alteration of 50 or more acres of land, unless the Project is consistent with an
approved conservation farm plan or forest cutting plan or other similar generallyaccepted
agricultural or forestry practices.
2. Creation of ten or more acres of impervious area.
(b) ENF and Other MEPA Review if the Secretary So Requires.
1. Direct alteration of 25 or more acres of land, unless the Project is consistent with an
approved conservation farm plan or forest cutting plan or other similar generallyaccepted
agricultural or forestry practices.
2. Creation of five or more acres of impervious area.
3. Disposition or change in use of land or an interest in land subject to Article 97 of the
Amendments to the Constitution of the Commonwealth, unless the Secretary waives or
modifies the replacement land requirement pursuant to M.G.L. c. 3, § 5A and its
implementing regulations.
4. Conversion of land in active agricultural use to nonagricultural use, provided the land
includes soils classified as prime, state-important or unique by the United States
Department of Agriculture, unless the Project is accessory to active agricultural use or
consists solely of one single family dwelling.
5. Release of an interest in land held for conservation, preservation or agricultural or
watershed preservation purposes, unless the Secretary waives or modifies the
replacement land requirement pursuant to M.G.L. c. 3, § 5A and its implementing
regulations.
6. Approval in accordance with M.G.L. c. 121A of a New urban redevelopment project
or a fundamental change in an approved urban redevelopment project, provided that the
Project consists of 100 or more dwelling units or 50,000 or more sq. ft. of nonresidential
space.
(2) State-listed Species under M.G.L. c. 131A (Massachusetts Endangered Species Act).
(a) ENF and Mandatory EIR. None.
(b) ENF and Other MEPA Review if the Secretary So Requires.
1. Alteration of designated significant habitat.
2. Greater than two acres of disturbance of designated priority habitat, as defined in
321 CMR 10.02: Definitions and Abbreviations, that results in a take of a state-listed
endangered or threatened species or species of special concern.
(3) Wetlands, Waterways and Tidelands.
(a) ENF and Mandatory EIR.
1. Provided that a Permit is required:
a. alteration of one or more acres of salt marsh or bordering vegetating wetlands; or
b. alteration of ten or more acres of any other wetlands.
2. Alteration requiring a variance in accordance with the Wetlands Protection Act.
3. Construction of a New dam.
4. Structural alteration of an existing dam that causes an Expansion of 20% or any
decrease in impoundment Capacity.
5. Provided that a Chapter 91 License is required, New non-water dependent use or
Expansion of an existing non-water dependent structure, provided the use or structure
occupies one or more acres of waterways or tidelands.
(b) ENF and Other MEPA Review if the Secretary So Requires.
1. Provided that a Permit is required:
a. alteration of coastal dune, barrier beach or coastal bank;
b. alteration of 500 or more linear feet of bank along a fish run or inland bank;
c. alteration of 1,000 or more sf of salt marsh or outstanding resource waters;
d. alteration of 5,000 or more sf of bordering or isolated vegetated wetlands;
e. New fill or structure or Expansion of existing fill or structure, except a pile-
supported structure, in a velocity zone or regulatory floodway; or
f. alteration of ½ or more acres of any other wetlands.
2. Construction of a New roadway or bridge providing access to a barrier beach or a
New utility line providing service to a structure on a barrier beach.
3. Dredging of 10,000 or more cy of material.
4. Disposal of 10,000 or more cy of dredged material, unless at a designated in-water
disposal site.
5. Provided that a Chapter 91 License is required, New or existing unlicensed non-water
dependent use of waterways or tidelands, unless the Project is an overhead utility line,
a structure of 1,000 or less sf base area accessoryto a single family dwelling, a temporary
use in a designated port area, or an existing unlicensed structure in use prior to January
1, 1984.
6. Construction, reconstruction or Expansion of an existing solid fill structure of 1,000
or more sf base area or of a pile-supported or bottom-anchored structure of 2,000 or more
sf base area, except a seasonal, pile-held or bottom-anchored float, provided the structure
occupies flowed tidelands or other waterways.
(4) Water.
(a) ENF and Mandatory EIR.
1. New withdrawal or Expansion in withdrawal of:
a. 2,500,000 or more gpd from a surface water source; or
b. 1,500,000 or more gpd from a groundwater source.
2. New interbasin transfer of water of 1,000,000 or more gpd or any amount determined
significant by the Water Resources Commission.
3. Construction of one or more New water mains ten or more miles in length.
4.
Provided that the Project is undertaken by an Agency, New water service to a
municipality or water district across a municipal boundary through New or existing
pipelines, unless a disruption of service emergency is declared in accordance with
applicable statutes and regulations.
(b) ENF and Other MEPA Review if the Secretary So Requires.
1. New withdrawal or Expansion in withdrawal of 100,000 or more gpd from a water
source that requires New construction for the withdrawal.
2. New withdrawal or Expansion in withdrawal of 500,000 or more gpd from a water
supply system above the lesser of current system-wide authorized withdrawal volume or
three-years’ average system-wide actual withdrawal volume.
3. Construction of one or more New water mains five or more miles in length.
4. Construction of a New drinking water treatment plant with a Capacity of 1,000,000
or more gpd.
5. Expansion of an existing drinking water treatment plant by the greater of 1,000,000
gpd or 10% of existing Capacity.
6. Alteration requiring a variance in accordance with the Watershed Protection Act,
unless the Project consists solely of one single family dwelling.
7. Non-bridged stream crossing 1,000 or less feet upstream of a public surface drinking
water supply for purpose of forest harvesting activities.
(5) Wastewater.
(a) ENF and Mandatory EIR.
1. Construction of a New wastewater treatment and/or disposal facility with a Capacity
of 2,500,000 or more gpd.
2. New interbasin transfer of wastewater of 1,000,000 or more gpd or any amount
determined significant by the Water Resource Commission.
3. Construction of one or more New sewer mains ten or more miles in length.
4.
Provided that the Project is undertaken by an Agency, New sewer service to a
municipality or sewer district across a municipal boundary through New or existing
pipelines, unless an emergency is declared in accordance with applicable statutes and
regulations.
5. New discharge or Expansion in discharge of any amount of sewage, industrial waste
water or untreated stormwater directly to an outstanding resource water.
6.
New Capacity or Expansion in Capacity for storage, treatment, processing,
combustion or disposal of 150 or more wet tpd of sewage sludge, sludge ash, grit,
screenings, or other sewage sludge residual materials, unless the Project is an Expansion
of an existing facility within an area that has already been sited for the proposed use in
accordance with M.G.L. c. 21 or M.G.L. c. 83, § 6.
(b) ENF and Other MEPA Review if the Secretary So Requires.
1. Construction of a New wastewater treatment and/or disposal facility with a Capacity
of 100,000 or more gpd.
2. Expansion of an existing wastewater treatment and/or disposal facility by the greater
of 100,000 gpd or 10% of existing Capacity.
3. Construction of one or more New sewer mains:
a. that will result in an Expansion in the flow to a wastewater treatment and/or
disposal facility by 10% of existing Capacity; or
b. five or more miles in length.
4. New discharge or Expansion in discharge:
a. to a sewer system of 100,000 or more gpd of sewage, industrial waste water or
untreated stormwater;
b. to a surface water of:
i. 100,000 or more gpd of sewage;
ii. 20,000 or more gpd of industrial waste water; or
iii.
any amount of sewage, industrial waste water or untreated stormwater
requiring a variance from applicable water quality regulations; or
c. to groundwater of:
i. 10,000 or more gpd of sewage within an area, zone or district established,
delineated or identified as necessary or appropriate to protect a public drinking
water supply, an area established to protect a nitrogen sensitive embayment, an
area within 200 feet of a tributary to a public surface drinking water supply, or
an area within 400 feet of a public surface drinking water supply;
ii. 50,000 or more gpd of sewage within any other area;
iii. 20,000 or more gpd of industrial waste water; or
iv.
any amount of sewage, industrial waste water or untreated stormwater
requiring approval by the Department of Environmental Protection of a variance
from Title 5 of the State Environmental Code for New construction.
5. New Capacity or Expansion in Capacity for:
a.
combustion or disposal of any amount of sewage sludge, sludge ash, grit,
screenings, or other sewage sludge residual materials; or
b. storage, treatment, or processing of 50 or more wet tpd of sewage sludge or
sewage sludge residual materials.
(6) Transportation.
(a) ENF and Mandatory EIR.
1. Unless the Project consists solely of an internal or on-site roadway or is located
entirely on the site of a non-roadway Project:
a. construction of a New roadway two or more miles in length; or
b. widening of an existing roadway by one or more travel lanes for two or more
miles.
2. New interchange on a completed limited access highway.
3. Construction of a New airport.
4. Construction of a New runway or terminal at an existing airport.
5. Construction of a New rail or rapid transit line along a New, unused or abandoned
right-of-way for transportation of passengers or freight (not including sidings, spurs or
other lines not leading to an ultimate destination).
6. Generation of 3,000 or more New adt on roadways providing access to a single
location.
7. Construction of 1,000 or more New parking spaces at a single location.
(b) ENF and Other MEPA Review if the Secretary So Requires.
1. Unless the Project consists solely of an internal or on-site roadway or is located
entirely on the site of a non-roadway Project:
a. construction of a New roadway one-quarter or more miles in length; or
b. widening of an existing roadway by four or more feet for one-half or more miles,
excluding widening to add bicycle or pedestrian accomodations.
2. Construction, widening or maintenance of a roadway or its right-of-way that will:
a. alter the bank or terrain located ten more feet from the existing roadway for one-
half or more miles, unless necessary to install a structure or equipment;
b. cut five or more living public shade trees of 14 or more inches in diameter at
breast height; or
c. eliminate 300 or more feet of stone wall.
3. Expansion of an existing runway at an airport.
4. Construction of a New taxiway at an airport.
5. Expansion of an existing taxiway at Logan Airport.
6. Expansion of an existing terminal at Logan Airport by 100,000 or more sf.
7. Expansion of an existing terminal at any other airport by 25,000 or more sf.
8. Construction of New or Expansion of existing air cargo buildings at an airport by
100,000 or more sf.
9. Conversion of a military airport to a non-military airport.
10. Construction of a New rail or rapid transit line for transportation of passengers or
freight.
11. Discontinuation of passenger or freight service along a rail or rapid transit line.
12. Abandonment of a substantially intact rail or rapid transit right-of-way.
13. Generation of 2,000 or more New adt on roadways providing access to a single
location.
14. Generation of 1,000 or more New adt on roadways providing access to a single
location and construction of 150 or more New parking spaces at a single location.
15. Construction of 300 or more New parking spaces at a single location.
(7) Energy.
(a) ENF and Mandatory EIR.
1. Construction of a New electric generating facility with a Capacity of 100 or more
MW.
2. Expansion of an existing electric generating facility by 100 or more MW.
3. Construction of a New fuel pipeline ten or more miles in length.
4.
Construction of electric transmission lines with a Capacity of 230 or more kv,
provided the transmission lines are five or more miles in length along New, unused or
abandoned right of way.
(b) ENF and Other MEPA Review if the Secretary So Requires.
1. Construction of a New electric generating facility with a Capacity of 25 or more MW.
2. Expansion of an existing electric generating facility by 25 or more MW.
3. Construction of a New fuel pipeline five or more miles in length.
4.
Construction of electric transmission lines with a Capacity of 69 or more kv,
provided the transmission lines are one or more miles in length along New, unused or
abandoned right of way.
(8) Air.
(a) ENF and Mandatory EIR.
1. Construction of a New Stationary Source with federal potential emissions, after
construction and the imposition of required controls, of: 250 tpy of any criteria air
pollutant; 40 tpy of any HAP; 100 tpy of any combination of HAPs; or 100,000 tpy of
GHGs based on CO2 Equivalent.
2. Modification of an existing Stationary Source with federal potential emissions that
collectively will result, after construction and the imposition of required controls, of
75,000 tpy of GHGs based on CO2 Equivalent.
(b) ENF and Other MEPA Review if the Secretary So Requires.
1. Construction of a New Stationary Source with federal potential emissions, after
construction and the imposition of required controls, of: 100 tpy of PM10, PM 2.5, CO,
lead or SO2; 50 tpy of VOC or NOx; 10 tpy of any HAP; or 25 tpy of any combination of
HAPs.
2. Modification of an existing Stationary Source resulting in a "significant net increase”
in actual emissions, provided that the stationary source or facility is major for the
pollutant. For purposes of this threshold, a "significant net increase" in actual emissions
shall mean an increase in emissions of: 15 tpy of PM10; 10 tpy of PM 2.5; 100 tpy of
CO; 40 tpy of SO2; 25 tpy of VOC or NOx; 0.6 tpy of lead.
(9) Solid and Hazardous Waste.
(a) ENF and Mandatory EIR. New Capacity or Expansion in Capacity of 150 or more tpd
for storage, treatment, processing, combustion or disposal of solid waste, unless the Project
is a transfer station, is an Expansion of an existing facility within a validly site assigned area
for the proposed use, or is exempt from site assignment requirements.
(b) ENF and Other MEPA Review if the Secretary So Requires.
1. New Capacity or Expansion in Capacity for combustion or disposal of any quantity
of solid waste, or storage, treatment or processing of 50 or more tpd of solid waste,
unless the Project is exempt from site assignment requirements.
2. Provided that a Permit is required in accordance with M.G.L. c. 21D, New Capacity
or Expansion in Capacity for the storage, recycling, treatment or disposal of hazardous
waste.
(10) Historical and Archaeological Resources.
(a) ENF and Mandatory EIR. None.
(b) ENF and Other MEPA Review if the Secretary So Requires. Unless the Project is
subject to a Determination of No Adverse Effect by the Massachusetts Historical
Commission or is consistent with a Memorandum of Agreement with the Massachusetts
Historical Commission that has been the subject of public notice and comment:
1. demolition of all or any exterior part of any Historic Structure listed in or located in
any Historic District listed in the State Register of Historic Places or the Inventory of
Historic and Archaeological Assets of the Commonwealth; or
2. destruction of all or any part of any Archaeological Site listed in the State Register
of Historic Places or the Inventory of Historic and Archaeological Assets of the
Commonwealth.
(11) Areas of Critical Environmental Concern.
(a) ENF and Mandatory EIR. None.
(b) ENF and Other MEPA Review if the Secretary So Requires. Any Project of ½ or more
acres within a designated ACEC, unless the Project consists solely of one single family
dwelling.
(12) Regulations and Planning.
(a) ENF and Mandatory EIR. None.
(b) ENF and Other MEPA Review if the Secretary So Requires.
1. Promulgation of New or revised regulations, of which a primary purpose is protecting
against Damage to the Environment, that significantly reduce:
a. standards for environmental protection;
b. opportunities for public participation in permitting or other review processes; or
c.
public access to information generated or provided in accordance with the
regulations.
2. Approval in accordance with M.G.L. c. 121B of a New urban renewal plan or a major
modification of an existing urban renewal plan.