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| Specifying that [[aggregates]] for the construction of LID practices must be free from fines is important. | | Specifying that [[aggregates]] for the construction of LID practices must be free from fines is important. |
| But checking that the delivered materials meet specification is essential to reduce problems with construction and longer term performance. | | But checking that the delivered materials meet specification is essential to reduce problems with construction and longer term performance. |
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| When possible, Construction Managers should observe the offloading of materials to watch for dust clouds. Aggregates or [[sand]] for LID construction should not give rise to clouds of dust when dumped. | | When possible, Construction Managers should observe the offloading of materials to watch for dust clouds. Aggregates or [[sand]] for LID construction should not give rise to clouds of dust when dumped. |
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| A simple jar test can be used to gauge the proportion of fines in an aggregate product before acceptance. | | A simple jar test can be used to gauge the proportion of fines in an aggregate product before acceptance. |
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| Apparatus: | | Apparatus: |
| *A large wide-mouthed jar - glass or clear plastic are both fine. | | *A large wide-mouthed jar - glass or clear plastic are both fine, |
| *Tap water, and | | *Tap water, and |
| *The aggregate to be tested. | | *The aggregate to be tested. |
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| Method: | | Method: |
| # Collect approximately 5 cm of material in the jar (or at least two complete layers of 40 mm clear stone), | | # Collect approximately 5 cm of material in the jar (or at least two complete layers of 50 mm clear stone), |
| # Add water to around 3/4 full, | | # Add water to around 3/4 full, |
| # Secure cap and shake, | | # Secure cap and shake, |
| # Leave for at least 30 minutes until the water is clear - longer is better, so overnight when possible, | | # Leave for at least 30 minutes and until the water is clear - plan to run the test overnight when possible, |
| # Examine the layer of sediment - if > 3 mm has been washed from 5 cm of product, reject the material, | | # Examine the layer of sediment - if > 3 mm has been washed from 5 cm of product, the material should be rejected, |
| Note that the sediment may collect on top of, or at the bottom of the construction material. | | Note that the sediment may collect on top of, or at the bottom of the construction material. |
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| ==External references== | | ==External references== |
| *Heger, S. (2014). Critical Aspects During System Installation and Inspection General equipment considerations. In PMSA conference. Retrieved from http://www.psma.net/pdf/14/conference-presentations/Keys to Installation (Heger).pdf | | *Heger, S. (2014). Critical Aspects During System Installation and Inspection General equipment considerations. In PMSA conference. Retrieved from http://www.psma.net/pdf/14/conference-presentations/Keys_to_Installation_(Heger).pdf |
| | *Manitoba. (2010). Onsite Wastewater Management Systems: Field Reference Guide - JAR TEST. Retrieved from http://www.gov.mb.ca/sd/envprograms/wastewater/pdf/jar_test_reference_03_2010.pdf |