Riverside County continues to monitor a possible underground fuel leak in Idyllwild. R.M. Environmental Inc. of Calimesa, conducting the monitoring work, just completed the third-quarter sampling report.

In addition, RME has submitted a work plan to install two more monitoring wells that will be sampled and monitored on a quarterly basis for the next 12 months. Both will be installed slightly west of the Ferrellgas office next to Muirs Realty.

RME is also planning to conduct a soil vapor extraction pilot test. This work, along with data from the two new monitoring wells, will be used to determine recommendations for future remediation if it is warranted, the report stated.

Since the June sampling, total hydrocarbon concentrations increased in four of the monitoring wells but decreased slightly in four other monitoring wells, according to the RME October report.

Methyl-tertiary-butyl ether continued to be detected in the site’s monitoring wells. MTBE concentrations in five of the wells sampled resulted in the highest recordings since June 2013. But it remained undetected in several more wells. Benzene concentrations increased in one well, but decreased in two wells.