3800 RIVERFRONT BLVD 2025-07-23 - Laserfiche WebLink

1 The City of Everett The Floyd & Snider Team Everett Landfill/Tire Fire Site 3.5 LANDFILL GAS MONITORING FOR DEVELOPMENT AREAS 3.5.1 ALARM SYSTEM Recommendations for future landfill conditions include a continuous sensor system in all ground floor spaces for all future buildings constructed at the site. The system will automatically activate increased interior ventilation via the installed HVAC system and notify appropriate operations and maintenance personnel if the methane concentration reaches 1,000 ppm. If methane concentration reaches 10,000 ppm, alarms will be actuated that will cause the building to be evacuated and the fire department notified. In case of power failure, the system will automatically switch to battery power and activate a trouble light or audible tone. The alarm system will be tested and approved for performance by a recognized testing laboratory in accordance with Fire Department recognized standards. 3.5.2 SAMPLING AND INSPECTION PLAN Building sampling and inspection will be performed alarm system described above and periodic sampling using methane detection field instruments capable down to less than five ppm. via two modes: the continuous sensing and inspection by a qualified technician of accurately measuring concentrations The continuous alarm system sensors will be placed in ground floor locations selected with consideration given to all possible gas entry locations and possible air dilution/diffusion from the point of entry to the sensor. The technician will check every ground floor room and/or enclosure within each building with the monitoring instrument. The breathing zone within the ground floor rooms will be tested generally. Any penetration of the building structure will be tested. Any penetration of the building structure will be tested. Penetrations include cracks in the floor and retaining walls, drains in floors, sinks, toilets, showers, and tubs, interior ends of incoming utility conduits, power panels, and phone panels or switchboxes. The technician will also check enclosed spaces outside the buildings. The technician will check these spaces by inserting the instrument probe into the space (no personnel entry). Enclosed spaces to be checked include spaces under buildings due to landfill settlement, spaces under portable buildings, manholes, catch basins, pump station vaults, and cracks in pavement or sidewalks. Other areas to be checked will include the ground surface around the perimeter of the buildings. 3.5.3 FREQUENCY OF SAMPLING Permanent sensors operate continuously and will be calibrated quarterly. The manual periodic monitoring survey will be performed every two weeks after the building and/or exterior area is opened for public access. If results do not show an air quality concern for three months, monitoring will then be performed quarterly. Monitoring P an\CM Everett LanOO.dfill\PDF maker -final docslCompliance Compliance Monitoring and Contingency Plan Monitoring Plan\CMCP 1 1-10-OO.doc FINAL - March 2001 Page 3-8 1 1 1 I] 1 1 1 1 1 1 1 1 1 1 1