S.A.V.E. Comments on draft rules for Gray Water in Montana
The Student Advocates for Valuing the Environment Foundation (S.A.V.E.) supports the use of gray water in Montana. Gray water used for irrigation and waste transfer has great potential to address issues of water quality and water quantity across Montana. While gray water use has a long history in rural agricultural communities in Montana, properly collecting and using gray water in today's structures is cutting edge. We greatly appreciate D.E.Q. staffs time, diligence, and expertise in bringing forth drafts of "Circular DEQ-4 (October 9, 2008)" and "Gray Water Reuse Rules (October 10, 2008)" to allow the benefits of gray water to be utilized while protecting public health and safety.
S.A.V.E. considers these documents to be well crafted, but do have some initial concerns and comments:
1. Soil categorization based on septic or black water treatment requirements for gray water irrigation. DEQ-4 Section 2.0, part B, number 3 states that test holes must be 7 feet deep. New rule language 17.36.103 requires ASTM standard D5921-96el. With gray water typically so close to the surface (about one to two feet), a maximum depth of 50 inches for test holes should be required and the criteria should be based on soil penetration near the surface, as with irrigation in agriculture or landscaping. In the case of a gray water irrigation being installed after a septic is already in place, this requirement could be burdensome and cost prohibitive, while not focusing exclusively on the absorption near the surface.
2. In the General Info Section, number 1.9, of DEQ-4, it states that the non-potable water must be identifiable through the use of "purple piping." We are understanding this to mean that the piping is identified with some sort of purple marking, probably durable tape, as PVC pipe is typically only available in white, black, and green colors. If that is not the case, an option should exist for labeling existing pipes in the case of any retrofit or the lack of availability of "purple piping."
3. Part 3, section 4, sets criteria for surge tanks that "may be incorporated" into irrigation system design. Certain systems, like the Brac line of gray water residential systems, which are readily available, can hold from 39 gallons designed for a home of up to three people (modelRGW-150) and up to 119 gallons for homes up to twelve people (RGW-450). If a system like this is installed and properly utilized for subsurface irrigation, it is important that the system's capacity not be considered a surge tank. A structure built to incorporate gray water systems is likely to have additional water saving features such as low flow faucets, low flow shower heads, and water saving washing machines. If this is the case, the installer should be able to size a surge tank based on less water use and best practices to control water demand. Smaller surge tanks should be allowed in this case.
S.A.V.E. looks forward to attending the Stakeholder/Task Force meeting on gray water this upcoming November 5. Parallel to the development of these rules, S.A.V.E. notes that it is in the interest of the State of Montana to provide resources for professional training, education, and research for this new realm of water conservation.
Matthew A. Elsaesser
The S.A.V.E. Foundation
P.O. Box 1481
Helena, MT 59624