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2017 MACC Annual Environmental Conference College of the Holy Cross Worcester, MA March 4, 2017 Presenters: Dwight R. Dunk, LPD, PWS Epsilon Associates, Inc. Michael Toohill, PWS, CE BSC Group, Inc. Delia Kaye Town of Concord Natural Resources Division
Reviewing Wetland Mitigation Plans
Objectives
Understanding the Science of Wetland Mitigation
Elements of a Mitigation Plan to Write Effective Orders of Conditions
Monitoring and Compliance
Regulations and the Science of Wetland Replication
http://www.nae.usace.army.mil/portals/74/docs/regulatory/Mitigation/2016_New_England_Compensatory_Mitigation_Guidance.pdf http://www.mass.gov/eea/docs/dep/water/laws/i-thru-z/replicat.pdf
Replication Under the WPA
Loss vs Alteration Replication vs Restoration Mitigation means rectifying an adverse impact by repairing, rehabilitating, or restoring the affected resource area, or compensating for an adverse impact by enhancing or providing replacement resource areas.
http://www.mass.gov/eea/docs/dep/service/regulations/310cmr10a.pdf page 46
Breaking Down the Criteria— 1. Size
What the WPA says (310 CMR 10.55 (4)(b)1):
“The surface of the replacement area to be created ("the replacement area") shall be equal to that of the area that will be lost ("the lost area")” i.e. “No Net Loss”
Using the Criteria—Size
1:1 required by the WPA USACE requirements for restoration or creation
range from 2:1 to 4:1 BUT, the USACE also accepts enhancement or
“in-lieu-of” fees Generally 1.5X provides adequate area to allow
for “edge failure”
Breaking Down the Criteria— 2. GW/SW Elevation and 4. Connectivity
What the WPA says (310 CMR 10.55 (4)(b)2):
“The ground water and surface elevation of the replacement area shall be approximately equal to that of the lost area”
And 310 CMR 10.55 (4)(b)4:
“The replacement area shall have an unrestricted hydraulic connection to the same water body or waterway associated with the lost area”
Using the Criteria—Groundwater & Surface Water During design there needs to be definitive evidence of
GW hydrology-Dig a Pit! Take a Boring! In the proposed replication area
On larger projects might want to add piezometers Beware of grading changes and project drainage
altering hydrology
Using the Criteria—Groundwater & Surface Water Incorporate a stream channel “Break into” the adjacent wetland Obtain spot grades after the rough cut and confirm GW
Breaking Down the Criteria— 3. and 5. Location What the WPA says (310 CMR 10.55 (4)(b)3):
“The overall horizontal configuration and location of the replacement area with respect to the bank shall be similar to that of the lost area”
And 310 CMR 10.55 (4)(b)5
“The replacement area shall be located within the same general area of the water body or reach of the waterway as the lost area”
Using the Criteria— Location, Location, Location Wetlands are a transition zone between purely upland
and purely aquatic communities, and the edge of the wetland is flagged at “the drier end” of the spectrum
Proximity to adjacent wetland Integrate into adjacent wetland Surface and groundwater connections Criteria 3 is tough to meet for Limited Project Crossings
Breaking Down the Criteria— 6. Revegetation Success Criteria and Erosion Control What the WPA says (310 CMR 10.55 (4)(b)6):
“At least 75% of the surface of the replacement area shall be reestablished with indigenous wetland plant species within two growing seasons, and prior to said vegetative reestablishment any exposed soil in the replacement area shall be temporarily stabilized to prevent erosion in accordance with standard U.S. Soil Conservation Service methods.”
Using the Criteria—Plants
Natives versus ornamentals (NEWFS natives cultivars)
Grown under proper conditions: anoxic/reduced/acidic conditions
Using the Criteria—Plants
Planting plans and schedules Planting in “motts”; not necessarily “random”
and not “uniform”
Using the Criteria—Plants (and Microbes and Animals!) Habitat/forage value of species chosen Microbial community
Using the Criteria—Soils
Re-using existing wetland soils Stockpiling existing wetland soils Moving/handling wetland soils At least 10% organic Mix: 1 compost:1 sand: 1 loam Beware screened loam!
Breaking Down the Criteria— 7. Consistency with all other Resource Area Performance Standards
What the WPA says (310 CMR 10.55 (4)):
“The replacement area shall be provided in a manner which is consistent with all other General Performance Standards for each resource area in Part III of 310 CMR 10.00. In the exercise of this discretion, the issuing authority shall consider the magnitude of the alteration and the significance of the project site to the interests identified in M.G.L. c. 131, § 40, the extent to which adverse impacts can be avoided, the extent to which adverse impacts are minimized, and the extent to which mitigation measures, including replication or restoration, are provided to contribute to the protection of the interests identified in M.G.L. c. 131, § 40.”
Using the Criteria—Other Resource Areas Bank Floodplain—replication and compensatory
storage? Riverfront—a “special case”—conversion of
Resource Areas
Using the Criteria—”Good” Science
Document hydrology Keep the soil “alive” Pick appropriate species Provide habitat/forage
Using the Criteria—”Good” Design
Rough grading “Final” grading Woody structure Hummocks Soil structure Hydraulic connection to adjacent wetland Build in “Phase 1” (minimize soil hold
time)
Using the Criteria—Monitoring Success Keep your eyes on SW and GW Install Monitoring and a Reference Plot Monitor Creation:
• Existing condition of replication are and the adjacent wetland
• Rough grade • Final grade • Plantings
Monitor Progress: • Frequency • Methods, Measures, and Reporting
Replication Design
Dwight Dunk
Elements of a Mitigation Plan & Writing Effective Orders of Conditions Drawings Mitigation Plan (Report or Specifications)
• Grading • Soil • Materials • Plant Palette • Execution • E&S Controls • Wildlife Controls
Schedule / Sequence of Work Construction Specifications (i.e. self-imposed conditions)
Drawings Existing Conditions Grading and E&S Plan (Plan and Cross-Sections)
Planting Plan Details
Elements of a Mitigation Plan & Writing Effective Orders of Conditions
Location Plan - relative to other site features and
fill area
Indicate access to
Replacement Area
Show Limit of Clearing
Cross-Sections
Existing Grade
Proposed Grade
Cross-Section Components
Existing Grade
Proposed Finish Grade
Sub Grade Grade
Planting Details
Planting Schedule-
Common Name, Latin Binomial,
Count, Size, Comments
Erosion and Sedimentation Control Details
Elements of a Mitigation Plan & Writing Effective Orders of Conditions
Mitigation Plan or Specifications Four critical milestones Pre-Construction Planning Site Preparation Construction Grading & Planting
Post –Construction Inspections
Elements of a Mitigation Plan & Writing Effective Orders of Conditions Pre-Construction (Conditions / Specifications)
Mitigation Schedule and Sequence Plan Soil storage protocol (if required) Grading Planting Inspection schedule Identify inspector
Soil Testing Results (manufactured soils) CO2 evolution for organic supplements Percent organic content Soil amendment recommendations from soil laboratory
Elements of a Mitigation Plan & Writing Effective Orders of Conditions
Pre-Construction Planning (Continued) Plant stock Source(s) Common name & Latin binomial needed Wildlife Use (food, nesting, perching, etc.) Quantity Replacements (if needed) On-site storage protocol
Inspect before installed
Scope of Work
Construction Elements
Submittals
Replication Plan: Schedule,
Sequence, Plant stock, Soils Sources, Seeding, Maintenance Monitoring
Manufactured Soil
Specifications
Percent Organic Content
Soluble Salts
pH
Soil Amendment Quality: C:N ratio CO2
evolution Free of
Pathogens
Plant Materials: Source, Condition Size
Elements of a Mitigation Plan & Writing Effective Orders of Conditions
Construction
Grading Plan Provided with NOI Establish sub-grade ~12 inches below finish
grade (inspect or require survey before finish grades established)
Finish grades (inspect or require survey before finish grades established)
Rough surface is good - microtopography
Elements of a Mitigation Plan & Writing Effective Orders of Conditions
Construction Soil conditioning (if required)
Lay out plant stock locations (Stake or mark planting zones)
Install plants per Nurseryman guidelines Irrigation required (tree and shrub saucers filled
twice after installation)
Execution
Plant Installation
Specifications
Specifications for: Digging plant
pits, Installing plants, Backfilling, Pruning, & Irrigation
Inspection Protocols: Methodology Defined
locations Frequency Season
Elements of a Mitigation Plan & Writing Effective Orders of Conditions
Post - Construction Construction completion inspection
End of growing season 1 inspection
End of growing season 2 inspection
Inspections: Initial (at Time of
planting) Intermediate (end of
first growing season) Final (end of second
growing season)
Inspection Reports
Define “Success” 75% cover in two growing seasons (per
310 CMR 10.55)
Writing Effective Orders of Conditions for Wetland Replication
Delia Kaye
Effective Orders of Conditions for Monitoring & Compliance How to condition your project for
successful mitigation Milestones How to determine if successful
mitigation has been achieved
Effective Orders of Conditions for Monitoring & Compliance Specify conditions for wetland mitigation Per approved plan and specs (use specs to develop conditions) Include condition that OOC and approved NOI plans onsite
Effective Orders of Conditions for Monitoring & Compliance Require an Environmental Monitor a qualified professional with a minimum of 5 years
experience in wetland delineation, replication design, monitoring, and construction oversight, and erosion and sedimentation control
EM resume is provided at least two weeks prior to construction for Commission/Agent approval
EM shall be independent of the Contractor with the ability to stop work if needed
EM to immediately contact the Commission in the event that there is a wetlands violation and the Contractor must take immediate steps to address the violation
Effective Orders of Conditions for Monitoring & Compliance EM contact info provided to the
Commission for 24/7 contact Pre-construction visit with the Engineer,
Contractor, Conservation Commission/Agent, and EM
Contractor to provide construction schedule to Commission/Agent at or before site visit
Effective Orders of Conditions for Monitoring & Compliance EM shall oversee all aspects of work related to wetland replication construction and monitoring
Wetland reflagging Erosion control installation When wetland replication area is excavated When soils are brought into the replication area Rough grade Final grade Before and when wetland plants are installed Monitoring
Effective Orders of Conditions for Monitoring & Compliance In OOC, require wetland replication occur during the first growing season of permit issuance
Increases chances that wetland replication will occur
Provides opportunity for evaluation during life of the permit
Provides opportunity to assess and address invasive species encroachment
Effective Orders of Conditions for Monitoring & Compliance Include condition for monitoring reports
Twice per year, through the life of the permit • at the beginning and end of the growing
season, with recommendations to address any problems
First report should include information on wetland construction and planting, with dates, forms, narrative, plan, and photos
Subsequent reports should document hydrology, hydric soils, plant success, recommendations for corrections – same format
Final report should document compliance with OOC, WPA, and Bylaw
Monitoring & Compliance Concord Wetland Replication Area Observation Plot Locations (Approximate)
Observation Plot #1
Observation Plot #2
“High Point” Observation Plot
(From 2015 LEC Monitoring Report)
Monitoring and Compliance
Soil Profile at Concord Observation Plot 2 (from 2015 and 2016 LEC Reports)
Monitoring and Compliance
Concord Observation Plot 2 (from 2015 LEC Report)
5-20-15 11-4-2015
Monitoring and Compliance
Concord Observation Plot 2 (from 2016 LEC Report)
6-10-16 10-13-16
Effective Orders of Conditions for Monitoring & Compliance
Certificate of Compliance A written statement by a P.E. or P.L.S registered in the
Commonwealth of MA that the Project has been developed in accordance with all terms and conditions of the OOC. Any existing deviations from the OOC and approved plans must be noted
As-built plans prepared by a P.E. or P.L.S. registered in the Commonwealth of MA showing the wetland replication area, with representative cross sections
A written report from a qualified wetlands professional that the wetland replication area has been constructed in accordance with the permit and the WPA (and Bylaw, if applicable)
Critical to ensure that correct replication area has been provided, and that 75% coverage has been achieved
THANK YOU
CONTACT INFO
Dwight Dunk: [email protected] Mike Toohill: [email protected] Delia Kaye: [email protected]
