To all Boards of Health
Re: Title 5, 310 CMR 15.000
Clarification of Distribution Line Specification
310 CMR 15.251(5)
Dear Board of Health Member:
As you may have noticed by now, there are errors contained in the soil absorption system pipe specifications described in 310 CMR 15.251(5) of Title 5 as it was promulgated. The purpose of this letter is to provide clarification of the acceptable material specifications for pipes to be used for distribution lines in leaching trenches, leaching beds, and leaching fields.
The Department would like to provide the following clarification:
Distribution lines for leaching trenches as referenced in 310 CMR 15.251(5) and for leaching beds and fields as referenced in 310 CMR 15.252(2)(h), shall be constructed of either polyvinyl chloride (PVC), acrylonitrile-butadiene-styrene (ABS), or high density polyethylene (HDPE). PVC pipe shall be schedule 40 General Purpose Sewer Pipe (ASTM D 1785), schedule 40 Drain, Waste and Vent Pipe (ASTM D 2665) or SDR 35 PVC Gravity Sewer Pipe and Drain Pipe (ASTM D 3034). ABS pipe shall be schedule 40 (ASTM F 628). HDPE pipe shall meet or exceed ASTM F 810 for Smoothwall Polyethylene Pipe for use in Drainage and Waste Disposal Fields.
The above is intended to clarify references to acceptable types of pipe and the ASTM standards which should apply to each type of pipe. Please note that smoothwall HDPE pipe is acceptable. The ASTM standard (ASTM F 810) for smoothwall HDPE pipe was included in the original regulation, but it was incorrectly referenced for ABS pipe without any reference to HDPE. The ASTM standard which should have been referenced for ABS pipe is ASTM F 628 and not ASTM F 405 or ASTM F 810. ASTM F 405 was inadvertently included in the regulation and is not considered acceptable since this specifies corrugated polyethylene coil pipe which is difficult to lay true to line and grade.
The above clarification, stated in bold, is also intended to address another inaccuracy of 310 CMR 15.251(5) which presently states, "PVC schedule 35 NSF may be used for systems designed for less than 2,000 gpd and where no vehicular traffic is anticipated." As stated in bold above, please note that the correct reference should be
'SDR 35 PVC Gravity Sewer Pipe and Drain Pipe (ASTM D 3034)'.
Concerning any proposed installation of systems over 2,000 gpd or where vehicular traffic cannot be avoided, it appears that SDR 35 PVC sewer pipe may be acceptable when properly installed, but the regulation does not allow for it at present. As a general consideration for any pipe material where vehicular traffic cannot be avoided, the Department recommends the designer provide documentation that the proposed pipe with the proposed bedding and cover can take H20 wheel loads.
Until such time as 15.251(5) is revised, hopefully this letter provides some interim guidance on soil absorption system distribution pipe specifications. The Department would like to encourage you to share this information with local designers and installers.