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North Andover Health Department
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Community and Economic Development Division
July 20, 2017
John.D. Sullivan, III P.E.
Sullivan Engineering Group, LLC
P.O. Box 2004
Woburn, MA 01888
Re: Subsurface Sewage Disposal System Plan for 800 Johnson Street(Map 38,Lot 106)
Dear Mr. Sullivan.:
The proposed wastewater system design plan for the above site dated June 21, 2017 and received
on June 23, 2017 has been reviewed. Unfortunately, the plan cannot be approved until the
following items are corrected. The specific section in Title 5: 31.0 CMR 15.000, or North
Andover regulation that is not met by this design-follows each itern where applicable.
1, On sheet 1 of 2, the foundation drain location and elevation were not shown (NA 3.2).
2. On sheet 2 of 2, the Design Analysis indicates the incorrect LTMR of 0,61 gpd/sf for a
percolation rate of 12 mins/irich in a Class 11 soil. It appears the pressure distribution
LIAR was used instead of the gravity L'I'AR. The correct LTAR is 0.56 gpd/sf in
accordance with 310 CMR 15.242(1)(a).
3. The design plan must indicate all stone in the leach field shall be double washed stone
(310 CMR 15.247(a-b).
4. On sheet 1 of 2, a Swale is required on the southern side of the leach field (3 10 CMR
15.255(2).
5. On sheet 2 of 2, the existing grade was not shown in the system profile view.
6. Orr sheet 2 of 2, the Leach Bed Detail indicates only the breakout elevation on the low
end of the leach field. The breakout elevation (98.65) on the high end should be
indicated as well.
7. On sheet 2 of 2, four septic tank model numbers are depicted and refer to 2-piece tanks.
Please indicate the model number for the proposed septic tank to assist the installer(NA
3.2).
8. Indicate if the proposed septic tank is H-10 or H-20.
9. Indicate the sire of the proposed manhole covers on the design plan.
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North.Andover I-lealth Department, Town Hall, 120 Main. Street,
North.Andover,MA 01.845 Phone: 978.688.9540 Fax: 978,688. 9542
Although not reasons for disapproval, you may wish to consider the following:
10. The primary and reserve leach fields are designed using the same LTAR but the
percolation rates are different. The primary leach field can be sized slightly smaller than
the reserve leach field based on the LTARs of 0.60 gpd/sf (9 mins/inch) and 0.56 gpd/sf
(12 mins/inch).
11. On sheet 1 of 2, it appears the finish grading on the eastern side of the leach field will
provide limited cover above the top of the impervious barrier. Please review the finish
grading to ensure appropriate cover material is provided above the barrier.
12. The slope of the longest pipe from the distribution box to the leach field lateral is
approximately 0.002. It is recommended to have slope of 0.01.
Please feel free to contact the office or Mill River Consulting at 978-282-0014 with any
questions you may have. We look forward to working with you to obtain a wastewater treatment
and dispersal system which will be in.compliance with all regulations and assure protection of
public health and the environment of North Andover,
Since ply,
Brian J. LaGrasse, CERT
Director of Public Health
cc: Robert Harding
File
Page 2 of 2
North Andover Health Department, Tower I.-fall, 120 Main Street,
North. Andover, MA 01845 Phone: 978.688.9540 Fax: 978.688.9542