routine checks. In addition to this, your operators must understand how to shut down the ROWPU for either short-term or
Conditions: Given the requirement to provide potable water supplies, the soldier, a water section NCOIC of an S&S
company in a field environment, must monitor water purification operations. Wear MOPP 4 when monitoring water
Standards: Review mission water requirements to meet total daily water needs of the supported force. Enforce
preventive maintenance program objectives. Provide expendable supplies (such as chemicals, POL, and filters) in
sufficient quantities to support purification operations. Coordinate DS/GS maintenance support required for purification
and related equipment. Conduct inspections of purification operations. Monitor raw and product water quality to
standards as outlined in Part I of this lesson.
Supervising ROWPU Startup. Before you can start up a ROWPU, you need to know its status at its last shutdown. For
instance, was it secured or drained, stopped for an emergency, or in a standby condition? Did it require a media filter
backwash or an RO element cleaning?
Monitoring Shutdown to Standby Status. The procedures you need to monitor when your personnel place a ROWPU into
standby status are:
That they shutdown to standby by fully opening the system pressure control valve and pushing the high-pressure pump
That they push the booster pump stop button when the feed flow drops below 60 GPM.
Then they need to push the chemical pump stop and raw water pump stop buttons.
The air compressor can be left on for short shutdowns. However, for shutdowns longer than one hour, the crew must turn off
the compressor as well as the main circuit breaker, and shut down the generator. If the ROWPU is kept in standby more than
three hours, the RO elements may lose performance and require cleaning. Personnel are to use the secured shutdown
procedure when long shutdown periods are anticipated, and when the media filter has not yet been backwashed.
Your crew can start up after being in standby shutdown mode with a media filter forward flush to waste. This flushes out
the usual surge of dirty water when the filter is being restarted. The flush needs to last three minutes. This procedure is
important for your crew to follow because you do not want to put dirt into the RO elements.
Monitoring Shutdown to Temporary Secured Status. Your operators are to use this shutdown procedure when the
ROWPU will be shut down from three hours to three days. To do this requires 525 gallons of potable water. Before shutting
down, operators must have a 5-gallon can filled with product water. They need to use it in the polyelectrolyte tank during the
start-up following shutdown. To temporarily secure the ROWPU, the operators need to backwash the media filter and flush
the system with potable water. A