HomeMy WebLinkAbout03/03/2025 - Gale Response Letter to NACC Questions - - 430 OSGOOD STREET w Gale Associates, Inc.
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March 3, 2025
Ms.Amy Maxner,Administrator
North Andover Conservation Commission
Town of North Andover
120 Main Street
North Andover, MA 01854
Re: Response to Comments
DEP#242-1045— NAHS Complex Partial Certificate of Compliance
DEP#242-1906—NAHS Athletic Field Improvements Notice of Intent
Dear Ms. Maxner and Commission Members:
On behalf of The Town of North Andover (TNA), Gale Associates, Inc. (Gale) is providing the
following response to written comments provided via email by Ms. Amy Maxner on February
10, 2025, written comments provided via email by Mr. Joseph Lynch,Jr. on February 13, 2025,
as well as verbal comments provided by the North Andover Conservation Commission (NACC)
at the February 12, 2025 and February 26, 2025 hearings related to the above referenced
projects. Plan and document changes resulting from the comments have been incorporated
into the accompanying submittal. (Responses are in bold)
Response to Conservation Administrator Inquiries:
The following are Gale's responses to review comments received email dated February 10,
2025, from Ms.Amy Maxner, Administrator, North Andover Conservation Commission.
1. The submittal has the current FEMA maps as opposed to the Preliminary maps -
Preliminary should be used.
Response: The plans have been revised to utilize the Preliminary FEMA map for the 100-
year flood line, refer to Enclosure 1 for revised plan sheets and Enclosure 6 for the
preliminary FEMA map.
2. 1 was expecting to see the limit of the 200' Riverfront Area project into the baseball
field... Can you please check with LEC about that - how close was the MHW to the
baseball field/did they delineate MHW along that stretch ?
Response: Per wetland sub-consultant LEC Environmental,the Cochichewick River travels in
a well-defined channel starting at the Chickering Road culvert near the southwest corner of
Walsh Stadium, and continues in a southeasterly direction away from the athletic facilities.
Further southeast, proximate to the tennis courts, this river system becomes a flooded
marsh due to two(2) beaver dams along the river, preventing evaluation and delineation of
the Mean Annual High Water (MAHW) mark. It is LEC's opinion that the historical aerial
imagery from 2013, available through Google Earth, can be used to provide a conservative
estimate of the MAHW. The plans have been updated to include this approximate MAHW
line and associated riverfront area, refer to Enclosure 1. The approximate 200ft riverfront
Page 1 of 9
North Andover Conservation Commission
Response to Comments "'CALE'
DEP#242-1045 & DEP#242-1906
March 3, 2025
area does not appear to project beyond the proposed improvements at the baseball field.
At the proposed tennis courts, overlap of the 200ft riverfront area is limited to a portion of
the proposed bituminous concrete pedestrian walkway.
3. Are the final results of the test boring available to share?
Response: See Enclosure 3 for final geotechnical evaluation report, which includes the
boring logs and evaluation.
4. Per the test pit data, there is a dense layer of glacial till - I am wondering if
water infiltrating through the new synthetic turf field and associated panel drains will
sheet along the top of that glacial till layer - will the new field result in water
behaving differently over the till and if so what would that look like, any resulting
conditions or impacts to be anticipated?
Response: Gale does not anticipate water sheet flowing along the top of the glacial till
layer. Rainfall that falls on the synthetic turf surface will drain vertically into the field base
stone and be contained via the concrete perimeter curb and outlet control structure. The
turf field will act as a detention chamber, allowing the water the opportunity to infiltrate.
5. 1 noticed in the Geotech report that they cited Mass DEP infiltration rates - how do these
compare to the test pit rates observed?
Response: Per Nobis's report: "...the USDA textural classifications for the soils encountered
in the test pits, below the topsoil, consisted primarily of loamy sand to sandy loam. Per the
MassDEP Stormwater Handbook(MSH)Volume 3,Table 2.3.3,the MassDEP recommended
infiltration rate varies from 2.41 inches per hour(in/hour)for a USDA textural classification
of loamy sand to 1.02 in/hour for a sandy loam. Based on the results of the infiltration
testing, the estimated hydraulic conductivity ranged from approximately 0.5 to 0.8
inches/hour." Please note, as recommended by third-party peer review through the
Limited Site Plan Review process, and in accordance with the MSH, Gale has revised the
stormwater design model to utilize an infiltration rate of 0.232 inches/hour. This does not
impact the stormwater design's ability to meet the MassDEP standards.
6. TSS removal worksheet lists the infiltration basin, and a drainage channel - is the
infiltration basin the existing subsurface basin, and I don't seem to see any drainage
channels proposed (can you point them out?)
Response: The "infiltration basin" refers to the synthetic turf field section. As described in
the report, the perimeter concrete curb and outlet control structure detain water within
the base stone, allowing stormwater the opportunity to infiltrate. The "drainage channel"
refers to the connection to the existing stormwater infrastructure.As noted in the report, it
is Gale's opinion that runoff directed into the synthetic turf field is relatively"clean" as the
field is not subject to routine vehicular loading, sanding or salting, and therefore does not
need to be treated for TSS removal. The third-party peer review has formally concurred
with this TSS analysis.
7. O&M notes "preventative maintenance" of the turf field -what exactly does this entail?
Page 2 of 9
North Andover Conservation Commission
Response to Comments "'CALE'
DEP#242-1045 & DEP#242-1906
March 3, 2025
Response: Preventative maintenance of the turf field includes regular grooming of the field
with a specialized attachment to redistribute the infill material within the field limits and
"stand-up" the turf fibers. The frequency of grooming depends on the level of play, but
most manufacturers typically recommend every two (2) to four (4) weeks. Other regular
maintenance items are limited to general debris cleanup and visual inspection of seams.
8. O&M of manholes&clean outs- is this done by a vac truck for both?
Response: Yes, this maintenance is performed by vacuum truck. The structures within the
limits of the turf field, with the exception of the outlet control structure, are smaller PVC
structures as opposed to full size precast concrete structures typically seen within
roadways.
9. Does the new field impact snow storage/management operations?
Response: Per NAHS, the location of the proposed multi-purpose turf field is not used for
snow storage. The existing synthetic turf fields are not currently plowed, and there are no
plans to plow the proposed multipurpose field. A newly proposed snow storage location
adjacent to the proposed field has been included in the revised post construction O&M
plan, refer to Enclosure 5.
10. How exactly will the existing subsurface infiltration basin be protected during
construction
Response: Refer to Enclosure 1, Sheet C011, Note 7. The area around the existing
subsurface infiltration basin is to be designated as an area of restricted loading, with
limitations on vehicular traffic, material unloading, and material placement. As part of the
construction of the synthetic turf field, the top of the basin will be covered with
approximately eight inches (8") of stone both during construction and at completion of the
project scope, refer to Sheet C201 for elevation differentials.
11. Do you anticipate any interaction with this subsurface basin during construction of the
field surface? If so, how should it be handled?
Response: Interaction with the subsurface basin will be limited to the placement,
compaction, and grading of the synthetic turf base stone. Additionally, the project scope
will include the inspection and cleaning of this structure during the demolition phase of
construction,as per the revised Plan Sheet C011, refer to Enclosure 1.
12. 1 don't see any discussion of dewatering in the submittal - with perched water observed
in the test pits, shouldn't we anticipate the need to manage water during excavation?
Please provide some narrative and plan details for that.
Response: Dewatering will be carried out by the selected contractor as necessary to
perform construction. See Enclosure 2 for dewatering Specification Section 3123 19 which
will be included in the bid documents,as well as Plan Sheet C514, Enclosure 1 for details.
13. Baseball field construction entrance is not shown as 50' on the Demo&EC plan, as shown
on the detail sheet
Page 3 of 9
North Andover Conservation Commission
Response to Comments "'CALE'
DEP#242-1045 & DEP#242-1906
March 3, 2025
Response: Plan Sheet C011 has been revised, refer to Enclosure 1.
14. Plan needs to show EC at all light pole locations within jurisdiction at Walsh.
Response: Plan Sheet C014 has been revised, refer to Enclosure 1.
15. Wetland restoration area needs to show EC along pavement removal and on either side
of restoration work.
Response: Plan Sheet C012 has been revised, refer to Enclosure 1.
16. There is a note on the tennis court Demo&EC plan that says "remove and dispose of 15"
of soil below proposed finish grades throughout the replication area" can you explain
the purpose of this- is the 15" unsuitable eroded material?
Response: Per wetland consultant LEC, this removal and disposal of 12" (previous plans
noted 15" in error, and have been revised to 12") of soil below finish grade is standard for
replication areas, as it provides an optimal strata for the proposed plants to take hold in
and is intended to limit the establishment of invasive species that may exist in the existing
soil.
17. Plant schedule on L101 does not list the quantity of proposed plants.
Response:The plant schedule on L101 lists spacing requirements for each plant,from which
the total quantity of each plant can be determined by the contractor given the proposed
area of replication.
18. Does it make sense to show the construction entrance for the tennis courts? It seems
obvious where it should be installed.
Response: Plan Sheet C012 has been revised, refer to Enclosure 1.
19. While on site last week, we observed tons of tennis balls in the wetland, the applicant
can anticipate being required to remove them and policing for this moving forward.
Response: (Voted.
20. The track plans should label the event area that is being re-worked (needs a name)
Response: Plan Sheet C103 has been revised to label this area as "Reworked Shot Put
Area", refer to Enclosure 1.
21. The track event area EC should connect with the stockpile area EC
Response: Plan Sheet C013 has been revised, refer to Enclosure 1.
22. Do you have any idea as to the most appropriate location for a construction entrance at
the track event area?
Response: The construction entrance location will be coordinated with the selected
contractor and Owner prior to construction start. One potential approach includes the use
of the existing access drive and placement of significant surface protections on the track
and turf field to allow vehicle and equipment crossings. An alternative approach could
include the provision of a temporary raised (stone or fill)access drive leading up to the shot
Page 4 of 9
North Andover Conservation Commission
Response to Comments "'CALE'
DEP#242-1045 & DEP#242-1906
March 3, 2025
put area.
Response to February 12t"Verbal Commission Member Inquiries:
The following are Gale's responses to verbal comments and directives provided by members
of the NACC at the February 12th hearing, recorded per Gale's understanding and
interpretation.
23. Please provide an Alternatives Analysis for work proposed within the 200ft Riverfront
Area of the Cochichewick River.
Response: Work proposed within the 200ft Riverfront Area is limited to the installation of
an athletic light pole at Walsh Stadium and the construction entrance and site walkways at
the tennis courts.See below analysis for these two(2)areas:
- The athletic light pole proposed at Walsh Stadium is one of two new poles proposed to
improve the lighting at the field. Currently, six poles (four along the north side, one on
the east side, and one on the west side) are used to light the northern half of the turf
field.The proposed improvements will update the existing lights to modern LED fixtures
and provide lighting for the lower half of the field. Attempting to light the lower half of
the field without an additional pole to the southwest would result in drastically
decreased lighting uniformity, as well as a decrease in average footcandles. To provide
adequate lighting to the southwest of the field, the fixture aiming would need to be
shallower, leading to more offsite light spill. The lack of a pole in this area would also
mean an inability to provide adequate modeling of objects on the field, as light would
not be coming from all sides of a potential object (such as a ball). In short, no
alternative location exists for this light pole that wouldn't also mean failing to
adequately light the field for athletic use.
- The proposed work at the tennis courts within the 200ft riverfront area includes the
temporary construction entrance for the tennis courts and the installation of a
bituminous concrete pedestrian pathway. Due to the proximity of BVW around the
tennis courts, no alternative construction entrance or walkway location exists that does
not disturb these wetlands. The pedestrian walkway is being relocated from its existing
location, which was over a culvert connecting two (2) areas of BVW that has since
collapsed.
24. Please provide an Alternatives Analysis for the selected infill material.
Response: The project is currently proposing the use of styrene-butadiene rubber (SBR) or
"crumb rubber" to be used for infill. The primary source for SBR is used vehicle tires. This
SBR is layered on top of sand at a ratio of approximately 30:70 to make up the W2 inches of
total infill depth. The sand serves primarily as a ballast to hold the turf carpet down, while
the SBR provides playability and shock absorption akin to a natural grass field. Gale has
experience with numerous different alternative infill options on the market, with the most
common alternatives Gale has utilized being an engineered wood fiber (BrockFILL or equal)
that is paired with sand or a polymer coated sand (Envirofill or equal) that makes up the
entire infill section. The material cost of both alternatives is higher than SBR, and both
alternatives also require the use of a shock pad, as the materials themselves do not have
the same shock absorbing qualities as SBR. Gale estimates that, for a field of this size, the
Page 5 of 9
North Andover Conservation Commission
Response to Comments "'CALE'
DEP#242-1045 & DEP#242-1906
March 3, 2025
increase in cost to utilize an engineered wood fiber(BrockFILL or equal) would be$250,000,
and the increase in cost to utilize a polymer coated sand (Envirofill or equal) would be
$500,000. These prices represent an approximate 13% and 25% increase, respectively, of
the total cost for the multipurpose athletic field. These alternatives would be cost
prohibitive for the District.
25. Please provide geotechnical borings logs.
Response: Refer to response to Question 3 above,see Enclosure 3.
26. Please provide information on Dark Sky Compliance with the proposed athletic lighting.
Response: Gale is working with an athletic lighting vendor to provide information related to
Dark Sky Compliance and will provide the associated documentation to NACC once
received.
27. Please provide a "drip edge" along the tennis court.
Response: Plan Sheet C202 has been revised to include an infiltration trench between the
tennis courts and Bordering Vegetated Wetlands(BVW), refer to Enclosure 1.
28. Please provide additional information on snow management.
Response: Refer to response to Question 9 above.
29. The existing conditions plan shows a shed which was installed within the 100ft buffer zone
of BVW without a permit. The plans appear to suggest that this shed is to remain. This
shed needs to be removed.
Response: Plan Sheets C011 and C101 have been revised to show the removal and
relocation of the shed outside the 100ft buffer zone, refer to Enclosure 1.
30. The existing conditions plan shows a gravel parking lot and access drive adjacent to the
baseball field with portions installed within the 100ft buffer zone, 50ft No-Build Zone
(NBZ) and 25ft No-Disturb Zone (NDZ) of BVW. The plans appear to suggest that this
gravel area is to remain.This gravel area needs to be removed.
Response: This topic was discussed further at the February 26t" hearing, refer to response
37 below.
31. The submitted Partial Certificate of Compliance (PCOC) lacks the necessary certification
that the original high school construction was performed in general accordance with the
permitted plans.
Response: Per previous conversation between Gale,the Town, and the Conservation Agent,
Gale cannot make this certification as they are not the engineer-of-record (EOR) and were
not involved in the design or implementation of the stormwater system for the 2001 High
School. Comparison of the as-built plan to the permit plans for the purpose of determining
deviations is to be performed by NACC, in cooperation with the Town Engineering
Department.
32. An outstanding item from the original high school Order of Conditions (OOC) is the lack of
submitted operation and maintenance logs for the stormwater system installed at the
high school since its construction.
Page 6 of 9
North Andover Conservation Commission
Response to Comments "'CALE'
DEP#242-1045 & DEP#242-1906
March 3, 2025
Response: It is Gale's understanding that certain maintenance activities have been
performed in the past and TNA will provide the associated records, if available. Additionally,
TNA recently engaged a third-party contractor to perform cleaning and inspection on
February 28t".The associated summary report will be provided to NACC once available.
Response to Written Commission Member Inquiries.
The following are Gale's responses to review comments received via email dated February 13,
2025, from Mr.Joseph Lynch,Jr., Member, North Andover Conservation Commission.
33. Provide full specification for turf fabric and infill materials. Provide alternatives analysis for
other infill choices, including comparison of water quality and ecological impacts.
Response: See Enclosure 2 for Specification Section 32 18 23 for proposed synthetic turf
and infill materials. Refer to response to Question 24 above for alternative analysis related
to infill materials. Gale has provided additional documentation specific to the proposed
materials and their environmental implications, refer to Enclosure 4.
34. Provide intended turf maintenance schedule and statement of Town's commitment to
adhere to schedule.
Response: Refer to response to Question 7. As part of the project specifications, the turf
manufacturer is to provide an 8-year warranty of the turf product, which typically
stipulates that the Owner perform the recommended routine maintenance to maintain the
warranty. It is Gale's opinion that this warranty requirement is sufficient to secure the
Owner's commitment to maintenance. As noted above, routine maintenance typically
consists of manual grooming every two (2)to four(4)weeks.
35. Provide product name and recommended application for cleaning, disinfection, and mold
control for the sports turf. Include frequencies and concentrations and cumulative impact
to water quality.
Response: Regular cleaning and disinfecting of the turf field is not a standard maintenance
item for outdoor facilities, similar to natural grass fields, due to their regular exposure to
UV light. The use of chemical cleaning agents is not proposed, required, or recommended.
36. Provide information on frequency and volume of material necessary for infill
replenish ment/replacement.
Response:The frequency and volume varies depending on the level of use and maintenance
practices for the fields. However, regular infill replenishment/replacement is not typically
necessary for fields using SBR as an infill. Loss of an amount of infill that would necessitate
significant replenishment is typically indicative of a field reaching the end of its usable life
(11 to 13 years)due largely to compaction and fiber layover.
Response to February 26t"Verbal Commission Member Inquires:
The following are Gale's responses to verbal comments and directives provided by members
of the NACC at the February 26t" hearing, recorded per Gale's understanding and
Page 7 of 9
North Andover Conservation Commission
Response to Comments "'CALE'
DEP#242-1045 & DEP#242-1906
March 3, 2025
interpretation.
37. Gravel drive can remain solely as an emergency access point for Walsh Stadium. Revise
as necessary.
Response: The gravel area layout has been revised to be limited to a ten-foot (10') wide
travel lane with minimum twenty-five-foot inside radii leading from the access road to the
southeast corner of Walsh Stadium, entirely outside of the fifty foot No-Build-Zone. The
remaining areas that are currently gravel will be loamed and seeded with
conservation/wildlife mix south of the gravel lane and a standard seed mix north of the lane.
The existing curb cut will be removed and replaced at a location outside of the NBZ, and a
locking vehicle gate will be added at this curb cut, along with an "Emergency Vehicles Only"
sign and timber guardrail adjacent to the gate to limit vehicle access. lastly, signage will be
placed along the southwestern side of the gravel drive noting that the area between the
BVW and the gravel drive is not to be mowed. Refer to Plan Sheet C102, Enclosure 1.
38. The applicant should potentially install fencing along the 50 ft NBZ adjacent to the gravel
drive and around the entrance point to limit access and disturbance.
Response: Gale proposes a "No-Mow" area adjacent to the gravel drive in lieu of a fence,
complete with associated signage. Timber guardrail will be added on either side of the
vehicle gate to further limit vehicle access to the area. Refer to Plan Sheet C102, Enclosure
1.
39. Covering over the existing subsurface detention galley is undesirable.Are there any other
options?
Response: Gale's understanding is that this subsurface detention galley was installed as
part of the original high school construction in 2001,and is part of the stormwater drainage
design for the parking lot. It is Gale's preference to avoid making alterations to previously
designed/installed stormwater systems. It is Gale's understanding that this chamber has
been functioning as intended since its install. Due to the chamber's central location, no
field layout exists that would avoid this chamber. As part of this project, the galley will be
inspected and cleaned, and the primary inspection port raised to just below the synthetic
turf to allow for periodic maintenance access. A BMP exhibit plan was produced as part of
the stormwater review, and has been updated to include the location of this raised port.
Refer to Enclosure 5.
40. Has the gravel parking area been modeled as impervious in the stormwater design?Since
the gravel area should not have existed in the first place, no credit can be claimed for
impervious surface removal for the gravel drive and loam and seed work described.
Response: The gravel area was included in the stormwater design, and was modeled as
"Gravel Road"with a Curve Number of 85.The previously submitted HydroCAD model was
designed assuming that the gravel area was remaining, and as such no credit is being taken
for reduction of impervious surfaces. Pending revisions to the model in response to third-
party peer review comments will maintain this condition.
Page 8 of 9
North Andover Conservation Commission
Response to Comments "'CALE'
DEP#242-1045 & DEP#242-1906
March 3, 2025
41. Please provide specifics of how the gravel area will be removed and replaced with loam
and seed.
Response: The full depth of the existing gravel is to be removed, and common fill used to
raise the grade as necessary to proposed sub-grade. The gravel emergency access lane will
be finished with 5" of washed %" crushed stone, and the grassed areas south of the lane
will be finished with 6" of loam and seeded with New England Conservation/Wildlife Mix
as manufactured by New England Wetland Plants, 14 Pearl Lane, South Hadley, MA or
approved equal. Refer to Plan Sheet C501, Enclosure 1. Grassed areas north of the lane will
be seeded with the standard on-site mix.
For additional context specific to the health and environmental implications of the proposed
synthetic turf system, please see Enclosure 4 for a selection of documents for the
Commissions reference.
- 2022 Weston &Sampson Letter to Gale Associates Re: Synthetic Turf and PFAS
- 2021 Hayley Aldrich Letter to a school considering turf fields Re: Evaluation of Health and
Environmental Effects: Synthetic Turf
- 2024 EPA Federal Research Action Plan on Recycled Tire Crumb
We hope you find our responses to the above comments satisfactory. Please do not hesitate
to call our office at (781) 335-6465 or reach out via email to kfr@gainc.com should you have
any comments or questions, or if you require additional information.
Best Regards
GALE ASSOCIATES, INC.
XYL&F. ?Z(xwa w/ta& yaw D. ThaJcorayOa&
Kyle F. Rowan Ryan D.Thackeray
Project Engineer Sr. Staff Designer
KFR/RDT/lad
Enclosures: 1. Revised Permit Plan Set (pages 10—54)
2. Specification Sections (pages 55—77)
3. Geotechnical Report (pages 78—150)
4. Environmental Documentation
4a. 2022 Weston &Sampson Letter(pages 151-158)
4b. 2021 Haley Aldrich Letter(pages 159—183)
4c. 2024 EPA FRAP (pages 184—395)
5. Snow Stockpiling/BMP Exhibit Plan (pages 396—398)
6. Preliminary FEMA Map (pages 399—400)
Page 9 of 9