{"id":8555,"date":"2018-04-19T03:49:37","date_gmt":"2018-04-18T19:49:37","guid":{"rendered":"https:\/\/www.envguide.com\/?p=8555"},"modified":"2018-05-24T02:41:27","modified_gmt":"2018-05-23T18:41:27","slug":"remediation-monitoring","status":"publish","type":"post","link":"https:\/\/us.envguide.com\/remediation-monitoring\/","title":{"rendered":"Remediation Monitoring"},"content":{"rendered":"

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Once the remedial action is implemented, monitoring is required to assess the protectiveness and effectiveness of the chosen interim remedial measures (IRM). The type and frequency of monitoring should be based on the CSM developed for the site which identifies the LNAPL type, source and distribution, site specific receptor issues, hydrogeologic influences on LNAPL behavior and other factors affecting LNAPL migration and recoverability. The operational monitoring should validate the assumptions developed for the site and document that the selected IRM is effective in preventing migration, reducing mass, when practicable, and is protective of known human and ecological receptors.<\/p>\n

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Type of Monitoring<\/p>\n\t\t\t\t\t<\/div>\n

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Monitoring the LNAPL Body<\/p>\n\t\t\t\t\t<\/div>\n

Since a remedial investigation should have resulted in a detailed understanding of the source(s) and distribution of the LNAPL at the site, it is anticipated that an appropriate monitoring well network was installed during the remedial investigation phase. This monitoring well network should include wells located within the LNAPL body and an appropriate array of wells around the perimeter of the LNAPL body. The spacing of these wells should reflect and account for site specific subsurface characteristics as well as the characteristics of the LNAPL being monitored. A sufficient number of monitoring points shall be located within the LNAPL body to establish and document LNAPL distribution, to predict behavior and migration and to assess recoverability. Perimeter wells should be located just beyond the LNAPL body, but close enough to verify that LNAPL is not migrating.<\/p>\n

Monitoring should be conducted on a regular basis at all LNAPL sites during the interim remedial measurement phase. Operational monitoring should include gauging events that collect depth to water (product 1: <\/a>), , depth to LNAPL and LNAPL thickness measurements (product 1:<\/a>) using appropriate field instruments. Adjustments in monitoring may be needed based on performance monitoring data and changing site conditions.<\/p>\n

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Receptor Monitoring<\/p>\n\t\t\t\t\t<\/div>\n

Receptor monitoring, if applicable, should be conducted to assess that the IRM is protective of known risks. The frequency will be based on the professional judgment of the investigator and should consider the CSM developed for the site. Receptor monitoring should be conducted in accordance with other relevant Guidance Documents and Regulations.<\/p>\n

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Interim Remedial Measure Monitoring<\/p>\n\t\t\t\t\t<\/div>\n

The specifics of remedial system monitoring will vary with the type of IRM selected for a site. All IRMs should include a means to monitor the response of the LNAPL body to remedial efforts and should include the collection of sufficient system data to allow an assessment of IRM effectiveness.<\/p>\n

An IRM monitoring protocol should include the following:<\/p>\n\t \n\t\t

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