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permission from adjacent landowners (especially for farm fields). • Install a pump and downstream distribution manifold depending on the project size. Generally, the main distribution line should reach 100 to 200-feet long (many large projects, or projects on tight soil, will require systems that reach several thou- sand feet long with numerous branch lines off of the main distribution line). • The manifold should have several valves, allowing for control over the distribution area in the field. • Install several branches of 4" schedule 20, swaged -fit common septic tight -lined sewer line, or 6" fire hose, which can convey the turbid water out to various sec- tions of the field. See lure 11-4.2.15 Manifold and Branches in a Wooded, Veget- ated Spray Field (p.382). • Determine the branch length based on the field area geography and number of branches. Typically, branches stretch from 200-feet to several thousand feet. Always, lay branches on contour with the slope. • On uneven ground, sprinklers perform well. Space sprinkler heads so that spray patterns do not overlap. • On relatively even surfaces, a level spreader using 4-inch perforated pipe may be used as an alternative option to the sprinkler head setup. Install drain pipe at the highest point on the field and at various lower elevations to ensure full coverage of the filtration area. Pipe should be place with the holes up to allow for a gentle weeping of stormwater evenly out all holes. Leveling the pipe by staking and using sandbags may be required. . To prevent the over saturation of the field area, rotate the use of branches or spray heads. Do this as needed based on monitoring the spray field. • Monitor the spray field on a daily basis to ensure that over saturation of any portion of the field doesn't occur at any time. The presence of standing puddles of water or creation of concentrated flows visually signify that over saturation of the field has occurred. • Since the operator is handling contaminated water, physically monitor the veget- ated spray field all the way down to the nearest surface water, or furthest spray area, to ensure that the water has not caused overland or concentrated flows, and has not created erosion around the spray nozzle. • Monitoring usually needs to take place 3-5 times per day to ensure sheet -flow into state waters. Do not exceed water quality standards for turbidity. , • Ecology strongly recommends that a separate inspection log be developed, main- tained and kept with the existing site logbook to aid the operator conducting inspec- tions. This separate "Field Filtration Logbook" can also aid the facility in 1 2014 Stormwater Management Manual for Western Washington Volume 11 - Chapter 4 - Page 380