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"Monitoring Program" section of the report (bottom of page 4), Chesney explains that later when the system is in use and being monitored, having the water samples tested by a certified laboratory will satisfy the requirement for system certification. This is not what the State Policy says or means. Third party certification/testing to document the validity of the system must occur before it can be considered and approved for use. There are many commercially available systems that have gone through NSF or other testing/certification programs that could be used for this project. There is nothing preventing the designer from seeking similar third-party testing and certification for this system to verify the merit and demonstrated performance of this design. 2. Inadequate Leaching Capacity. While the proposed design is may be an effective way of promoting vegetative uptake of nitrogen, it fails to provide the necessary leaching capacity for the 4-bedroom residence it will serve. The design proposes to use (9) 35-ft long lengths of 12-inch diameter EZflow drain modules spaced 2-ft apart; the space between the modules will be packed with native soils. The infiltrative area beneath the EZflow modules totals 315 ft2(9 x 1' x 35'), which is all that can be credited as leaching area; the areas backfilled with soil between the modules cannot be considered effective leaching area. Multiplying 315 ft2 of leaching area times the application rate of 0.686 gpd/ft2 cited in the design report gives a total leaching capacity of 216 gpd, which is well short of the standard of 560 gpd for a 4- bedroom house (based on 140 gpd per bedroom). On page 5 of the design report, Chesney claims a leaching capacity of 600 gpd, based on 0.686 gpd/ft2 applied to the overall dimensions of the excavated bed(25' x 35'= 875 ft). Chesney includes credit for 560 ft2 of area backfilled with soil, which is not supportable by any code, studies or industry practice that I am aware of. As a result, the proposed design provides inadequate leaching capacity and would have to be nearly tripled in size to meet the leaching capacity requirements for a 4-bedroom house. 3. Other Design Issues. There are other design issues that would also have to be addressed if the comments in 1 and 2 above can be resolved, as follows: • Clogging of EZflow. The EZflow drain modules specified come with a half-section of filter fabric secured over the top, and the lower half open for dispersal of effluent into the adjacent native soil. The proposed design will backfill with loose soil around the entire module with the additional intent of encouraging roots to extend around and into the EZflow aggregate. This poses a serious risk of soil and root intrusion and potential clogging of void spaces within the geosynthetic aggregate. The designer should provide technical review and concurrence of this proposed application of EZflow drainage modules from the manufacturer, specifically addressing the risk and possible consequences of clogging by soil and/or root intrusion. • Equal Effluent Distribution. Based on the design rationale, the system is highly dependent on effluent being spread equally over the entire leaching-filter bed in order to support a uniform growth of fescue grass over the entire bed. Vegetation management and the theoretical projections of nitrogen uptake rely on uniform effluent dispersal. Gravity piping systems, such as that proposed, are susceptible to the development of 2