Lead pipe test rigs

Lead several approaches can be used in combination to demonstrate the success (or otherwise) or corrective actions (i) benchmark monitoring at selected houses which have lead pipe-work (see Section 3.4), (ii) lead pipe test rigs at strategic locations (see Section 10.2), and (iii) zonal surveys - random daytime samphng from consumers taps wiU provide the most representative check of variation across the water supply system. 

As described in Section 10.2, lead pipe test rigs can be installed at strategic locations within a water supply system. A typical deployment would be (i) treated water at the treatment works, before orthophosphate dosing, (ii) treated water at the treatment works, after ortho-phosphate dosing, (iii) within the near distribution system, close to the treatment works, and (iv) within the far distribution system, distant from the treatment works. 

Installation of lead pipe test rigs at appropriate locations (Section 10.2), or repeated stagnation sampling of suitable reference houses, or both. 

In the lead pipe test rig shown, the operating principles are ... 

Results from automated lead pipe test rig... 

DWI s initial preference for optimisation to be demonstrated by fixed point stagnation sampling. In practice, stagnation sampling from houses was found to be difficult to sustain, and the use of lead pipe test rigs was only partially successful. 

RDT or 30MS sampling are appropriate for identifying areas that require priority action to reduce lead levels. Previous studies show that the lead pipe test (pipe rigs at the treatment facility) can also be suitable for this purpose. 

Slides Tungsten filaments, turbine blades, lead drain pipes and organ pipes, glaciers creep-testing rigs micrographs of creep cavities. 

Until now simplified methods have been available to monitor metal release by metallic pipe materials. In the United Kingdom a sit-and-soak test is available to determine the metal release from drinking water materials. In The Netherlands, copper and lead pipes in combination with water quality are tested in pipe rigs, and in Germany a protocol for testing pipe materials is available (see below). 

For copper, the rig tests are applied at pumping stations where the water has a high copper solubility. For lead, the rigs are plaeed at the majority of the pumping stations that deliver water to areas with lead pipes. The results from the pipe rig test show a good correlation with metal concentrations at the tap. The Netherlands government has accepted the pipe rig test for compliance monitoring. 

Figures 10.5 and 10.6 give illustrative results from test rigs using new lead pipe.

Pipe rig tests in the Netherlands In The Netherlands in the mid 1980s a pipe rig was developed and used at several pumping stations to measure lead and copper concentrations in the drinking water. The rig consists of three pipes through which water is flowed continuously except when sampling. The flow rate is about 0.05 m/s. The metal concentration in the drinking water is measured after 24-hour stagnation. 

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