Code of Massachusetts Regulations
301 CMR - EXECUTIVE OFFICE OF ENERGY AND ENVIRONMENTAL AFFAIRS
Title 301 CMR 11.00 - Mepa Regulations
Section 11.03 - Review Thresholds

Universal Citation: 301 MA Code of Regs 301.11

Current through Register 1531, September 27, 2024

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 generally accepted 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 generally accepted 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.

7. 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.

(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, 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 1/2 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 accessory to 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 1/2 or more acres within a designated ACEC, unless the Project consists solely of one single family dwelling.

(12) Regulations.

(a) ENF and Mandatory EIR. None.

(b) ENF and Other MEPA Review if the Secretary So Requires. Promulgation of New or revised regulations, of which a primary purpose is protecting against Damage to the Environment, that significantly reduce:
1. standards for environmental protection;

2. opportunities for public participation in permitting or other review processes; or

3. public access to information generated or provided in accordance with the regulations.

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