Changes

For underground conveyances (i.e., catchbasins, manholes, [[pipes]]), BMPs, [[pretreatment]] devices, and in-line [[Media filters|filters]], sediment removal often requires crews performing the work to enter confined spaces. Contractors or staff performing the work must have confined space entry training to satisfy occupational health and safety requirements ([https://www.ontario.ca/laws/regulation/050632#:~:text=(1)%20Every%20worker%20who%20enters,632%2F05%2C%20s. Ont. Reg. 632/05 – Confined Spaces Regulation]). <br>

For underground conveyances (i.e., catchbasins, manholes, [[pipes]]), BMPs, [[pretreatment]] devices, and in-line [[Media filters|filters]], sediment removal often requires crews performing the work to enter confined spaces. Contractors or staff performing the work must have confined space entry training to satisfy occupational health and safety requirements ([https://www.ontario.ca/laws/regulation/050632#:~:text=(1)%20Every%20worker%20who%20enters,632%2F05%2C%20s. Ont. Reg. 632/05 – Confined Spaces Regulation]). <br>

How the material removed from conveyances, LID BMPs, [[pretreatment]] devices and in-line filters will be safely and sustainably managed also needs consideration. Due to the small drainage area of most LID BMPs, the rate at which they accumulate sediment and associated contaminants tends to be low in comparison to centralized stormwater treatment facilities like [[SWM ponds|stormwater ponds]] or detention chambers/tanks that receive drainage from much larger areas. As a result, the potential for sediment accumulated in LID BMPs to qualify as contaminated according to [https://www.ontario.ca/page/soil-ground-water-and-sediment-standards-use-under-part-xv1-environmental-protection-act Ontario Brownfields Regulation 153/04 standards for soil and sediment (OMOE, 2011)] is low. <br>

How the material removed from conveyances, LID BMPs, [[pretreatment]] devices and in-line filters will be safely and sustainably managed also needs consideration. Due to the small drainage area of most LID BMPs, the rate at which they accumulate sediment and associated contaminants tends to be low in comparison to centralized stormwater treatment facilities like [[SWM ponds|stormwater ponds]] or detention chambers/tanks that receive drainage from much larger areas. As a result, the potential for sediment accumulated in LID BMPs to qualify as contaminated according to [https://www.ontario.ca/page/soil-ground-water-and-sediment-standards-use-under-part-xv1-environmental-protection-act Ontario Brownfields Regulation 153/04 standards for soil and sediment (Ministry of the Environment, 2011)<ref>Ministry of the Environment. 2011. Soil, ground water and sediment standards for use under Part XV.1 of the Environmental Protection Act. This document provides Ontario’s soil, ground water and sediment standards effective July 1, 2011. PIBS # 7382e01. https://www.ontario.ca/page/soil-ground-water-and-sediment-standards-use-under-part-xv1-environmental-protection-act</ref>] is low. <br>

Most often, contractors or staff performing sediment removal maintenance procedures will be cleaning multiple BMPs and pretreatment devices at multiple sites on any given day. At the end of the day, the mixture of material collected either manually, or by vacuum equipment (e.g., regenerative air or vacuum sweeper, vacuum/soil blower truck, hydro-vac truck) will include a mixture of re-usable, recyclable and non-recyclable constituents. In order to recover reusable and recyclable materials and minimize the volume of material needing to be managed otherwise, the mixture should be screened to isolate trash (for recycling or disposal), natural debris and [[mulch]] (for composting), and [[gravel]] - to pebble-sized [[aggregates]] (for washing and re-use) from finer (i.e., [[sand]] - to [[Texture|clay-sized]]) material. The sand- to clay-sized material (i.e., material passing a 2 mm diameter ([https://www.endecotts.com/faq/sieves-and-calibration/american-standard-test-sieve-series-astm/ ASTM No. 10]) sieve) should then be assessed and managed in accordance with [https://www.ontario.ca/laws/regulation/900347 provincial regulations (O.Reg. 347)].

Most often, contractors or staff performing sediment removal maintenance procedures will be cleaning multiple BMPs and pretreatment devices at multiple sites on any given day. At the end of the day, the mixture of material collected either manually, or by vacuum equipment (e.g., regenerative air or vacuum sweeper, vacuum/soil blower truck, hydro-vac truck) will include a mixture of re-usable, recyclable and non-recyclable constituents. In order to recover reusable and recyclable materials and minimize the volume of material needing to be managed otherwise, the mixture should be screened to isolate trash (for recycling or disposal), natural debris and [[mulch]] (for composting), and [[gravel]] - to pebble-sized [[aggregates]] (for washing and re-use) from finer (i.e., [[sand]] - to [[Texture|clay-sized]]) material. The sand- to clay-sized material (i.e., material passing a 2 mm diameter ([https://www.endecotts.com/faq/sieves-and-calibration/american-standard-test-sieve-series-astm/ ASTM No. 10]) sieve) should then be assessed and managed in accordance with [https://www.ontario.ca/laws/regulation/900347 provincial regulations (O.Reg. 347)].

[[File:Key Design and Plan Review Considerations Schematic.png|thumb|600px|Recommended process for determining reuse and disposal options for sediment from stormwater management BMPs. [https://sustainabletechnologies.ca/app/uploads/2018/04/SWMFG2016_Guide_April-2018.pdf Source: Inspection and Maintenance Guide for Stormwater Management Ponds and Constructed Wetlands (TRCA and CH2M, 2016)]<ref name="example1">Citation: Toronto and Region Conservation Authority (TRCA) and CH2M Canada. 2016. Inspection and Maintenance Guide for Stormwater Management Ponds and Constructed Wetlands. Toronto and Region Conservation Authority, Vaughan, Ontario. https://sustainabletechnologies.ca/app/uploads/2018/04/SWMFG2016_Guide_April-2018.pdf</ref>. <br>

[[File:Key Design and Plan Review Considerations Schematic.png|thumb|600px|Recommended process for determining reuse and disposal options for sediment from stormwater management BMPs. [https://sustainabletechnologies.ca/app/uploads/2018/04/SWMFG2016_Guide_April-2018.pdf Source: Inspection and Maintenance Guide for Stormwater Management Ponds and Constructed Wetlands (TRCA and CH2M, 2016)]<ref name="example1">Citation: Toronto and Region Conservation Authority (TRCA) and CH2M Canada. 2016. Inspection and Maintenance Guide for Stormwater Management Ponds and Constructed Wetlands. Toronto and Region Conservation Authority, Vaughan, Ontario. https://sustainabletechnologies.ca/app/uploads/2018/04/SWMFG2016_Guide_April-2018.pdf</ref>. <br>

<small>'''Note:''' This flow chart does not depict OMOECC policy but rather a recommended approach based on TRCA’s understanding of current OMOECC operational practices.</small>]]

<small>'''Note:''' This flow chart does not depict MECO policy but rather a recommended approach based on TRCA’s understanding of current MECP operational practices.</small>]]

Laboratory testing to determine if beneficial reuse (e.g., spreading on landscaped areas or blending with other constituents for use as a soil conditioner) of the remaining sand- to clay-sized constituents is an option that should be considered. Determining beneficial reuse options for all constituents of the accumulated material could provide substantial savings in terms of costs associated with transporting and managing the material off-site. For more detailed guidance on what types of testing should be done on sediment accumulated in SWM BMPs and what standards to apply to determine when beneficial re-use is an option, refer to [https://sustainabletechnologies.ca/app/uploads/2018/04/SWMFG2016_Guide_April-2018.pdf Chapter 9 of the Inspection and Maintenance Guide for Stormwater Management Ponds and Constructed Wetlands] (TRCA and CH2M, 2016)<ref name="example1" />. The following flow chart (to the right of the page) provides an overview of the process recommended in the aforementioned guide for determining sediment reuse and disposal options.

Laboratory testing to determine if beneficial reuse (e.g., spreading on landscaped areas or blending with other constituents for use as a soil conditioner) of the remaining sand- to clay-sized constituents is an option that should be considered. Determining beneficial reuse options for all constituents of the accumulated material could provide substantial savings in terms of costs associated with transporting and managing the material off-site. For more detailed guidance on what types of testing should be done on sediment accumulated in SWM BMPs and what standards to apply to determine when beneficial re-use is an option, refer to [https://sustainabletechnologies.ca/app/uploads/2018/04/SWMFG2016_Guide_April-2018.pdf Chapter 9 of the Inspection and Maintenance Guide for Stormwater Management Ponds and Constructed Wetlands] (TRCA and CH2M, 2016)<ref name="example1" />. The following flow chart (to the right of the page) provides an overview of the process recommended in the aforementioned guide for determining sediment reuse and disposal options.