Page 142
December 2009
Water System Design Manual
treatment efficiency or operation costs will not match pre-design expectations, and either major
modification or complete abandonment of the approach may be required. Submittals for full-
scale pilot testing should identify actions the engineer will take if it is necessary to make major
modifications or abandon the project.
Water systems may use water from full-scale pilot tests for public consumption if they meet all
of the following conditions:
1.
Source capacity limitations on an existing water system do not provide adequate source
capacity for the combined demand of the existing customers and the pilot study.
2.
Application of the treatment device does not increase the level of any primary water
quality contaminant with an established MCL.
3.
Start-up, testing, and operation procedures are approved as part of a pilot-study plan.
4.
The treatment system technology:
a.
Received DOH approval for demonstrating adequate removal of specific
contaminants.
b.
Is an approved alternative filtration technology for surface water applications.
c.
Is constructed of components that do not leach or otherwise add substances to the
finished water as demonstrated through third party testing that meets the requirements
of ANSI/NSF Standard 61.
DOH may waive the pilot study for:
·
Identical treatment processes on nearly identical source waters, such as reverse osmosis
on well-circulated seawater.
·
Some groundwater treatment projects that use an identical treatment process and have
similar water quality data. Analogous system criteria for groundwater include:
Less than 5 percent variability of raw water pH.
5 percent variability of raw water total organic carbon (applies if greater than 2
mg/L).
20 percent variability of raw water primary and secondary IOCs.
There are no analogous criteria for any surface water treatment technologies. Analogous surface
water sources are rare. However, in some isolated cases, a design engineer may justify limited or
reduced piloting for surface water treatment. DOH anticipates this will include only water
systems with similar withdrawal points from the same water source.
Equipment for proprietary processes is usually so specialized that pilot testing results are unique
to a specific equipment design. For example, differences in low-pressure membrane filtration
make it impractical to transfer pilot results from one proprietary design to another. These
differences include: