|
Mr. Brendan P. Kenny, RG
<br />Corrective Action Program Update - 2Q2025
<br />July 11 2025
<br />Page 2
<br />On 30 April 2025, three gas probes had methane concentrations exceeding 1% by volume. GP-
<br />10D had an observed methane content of 42% by volume, GP-10M had an observed methane
<br />content of 41.8% by volume, GP-10S had an observed methane content of 35.8% by volume.
<br />On 30 April 2025, GP-1AD, GP-1AS, GP-2AD, GP-2AS, GP-6AM, GP-6AS, GP-10D, GP-
<br />10M,GP-10S and GP 11S had observed VOC exceedances of 600 ppbv, 3,500 ppbv, 4,500 ppbv,
<br />2,000 ppbv, 1,000 ppbv, 2,500 ppbv, 3,000ppbv, 1,500 ppbv, 5,500 ppbv, 6,200 ppbv, 4,600 ppbv
<br />and 2,500 ppbv, respectively which were above 10 ppbv.
<br />Based on the requirements in the CAO and on the above monitoring results, probes GP-1AD, GP-
<br />1AS, GP-2AD, GP-2AS, GP-6AM, GP-6AS, GP-10D, GP-10M,GP-10S and GP 11S will require
<br />annual TO-15 sampling due to methane concentrations exceeding 1 percent by volume and VOC
<br />concentrations exceeding 10 ppbv. The TO-15 sampling of these probe intervals will be conducted
<br />on an annual basis in accordance with the CAO and submitted as part of the Landfill Gas
<br />Extraction System Optimization Report.
<br />The 2025 second quarter probe monitoring data are shown in Table 1.
<br />CONTROL SYSTEM PERFORMANCE MONITORING
<br />The site sends its LFG to two onsite flares for combustion and to the onsite landfill gas to energy
<br />(LFGTE) plant operated by Ameresco. SCS operated and monitored the GCCS including the flares
<br />in the second quarter of 2025.
<br />The average flow rates to FL-100 and FL-150 were 1,544 scfm and 1,406 scfm, respectively. The
<br />average methane content was 47% by volume at flare FL-100 and 46.8% at flare FL-150.
<br />Flare FL-100 had a total run time of 708.73 hours and a total down time of 11.27 hours in April
<br />2025, a total run time of 725.93 hours and a total down time of 18.07 hours in May 2025 and a
<br />total runtime of 694.78 hours and a total down time of 25.21 hours in June 2025. Flare FL-100
<br />recorded a maximum adjusted flow of 1,680 standard cubic feet per minute (scfm) .
<br />Flare FL-150 had a total runtime of 708.72 hours and a total downtime of 11.28 hours in April
<br />2025, a total runtime of 713.05 hours and downtime of 30.95 hours in May 2025 and, a total
<br />runtime of 663.5 hours and a total downtime of 56.5 hours in June 2025. Flare FL-150 recorded a
<br />maximum adjusted flow of 1550 scfm.
<br />A plume of methane was detected at the site by a satellite-based instrument on 25 th June 2025.
<br />California Air Resources Board (CARB) notifies Republic Services about the same. Flare FL-100
<br />was shutdown from 7:44 am to 7:12 pm, while flare FL-150 was shutdown from 7:44 am to 7:13
<br />pm for source testing.
<br />Except for standard flare malfunctions or shutdowns, the GCCS was operated continuously 24
<br />hours per day without any significant downtime flare time.
<br />Q2 Corrective Action Program Update - 2025
|