Michigan's new Lead and Copper Rule has led to changes in sampling procedures and bottle kits for drinking water samples submitted to the state laboratory.
The state laboratory has upgraded the bottle for Total Coliform/E. coli samples from a 120 mL bottle to a 150 mL bottle. To allow for proper mixing of the sample in the bottle upon receipt at the laboratory, there needs to be 1-inch of air, or headspace, in the bottle. The test also requires 100 mL of water. By increasing the volume of the bottle, there is more flexibility when sampling and both requirements are more likely to be met.
In addition, water suppliers are required to test the first and fifth liter of water from a primary tap in homes connected to lead service lines, under the new Michigan Lead and Copper Rule. Water must be stagnant in the system for at least six hours prior to sampling. By sampling the first liter of water, the lead and copper content due to the home's plumbing (pipes, fittings, fixtures, solder) can be measured. This first liter of water does not include stagnant water directly from the service line, while the fifth liter of water is more likely to contain water from the lead service line. By submitting two samples of drinking water from lead service line homes, water suppliers will be better equipped to evaluate if corrosion control is effectively treating the multiple potential sources of lead in plumbing and service lines. Previously, water suppliers were only required to test the first liter of water collected from a tap.
For more information about the Michigan Lead and Copper Rule, check out this brochure.
For more information about EGLE's Laboratory Services, visit the website.