Groveland manhole overflows

As officials with the Groveland Community Services District and the California Regional Water Quality Review Board work out a possible settlement over two sewage spills in 2010, GCSD crews dealt with another wastewater spill this month.

According to Tuolumne County Environmental Health, GCSD crews responded to an overflow out of a manhole on Pleasant View Drive near Pine Mountain Lake on the night of Jan. 18.

As much as 100 gallons of sewage leaked behind a house, some of which likely reached Second Garrote Creek, a tributary near Pine Mountain Lake, according to Environmental Health.

istrict staff posted notices in the area of the spill, which district General Manager Gary Mello said was the result of grease and other items clogging the line. According to Environmental Health, testing will continue and on-site notices would remain until bacteria levels drop.

Last week, Mello said the spill cleanup took place near the manhole and involved spreading a disinfectant and removing about 50 gallons of contaminated material.

Mello said they initially believed none of the spill, which he estimated at “less than” 100 gallons, reached a waterway. But lab results indicated some amount may have reached the creek, Mello said.

He also said he it’s not clear if the results were due solely to the spill.

Mello said inspection at the creek revealed animal tracks and waste near the waterway. He said district personnel will now conduct quarterly testing of all the existing waterways in the district and compile a database of the “background level” of possible contaminants.

“The problem is with the environment along these creeks, it’s difficult to know for sure when you have test results whether or not you’re getting evidence of sewer effluent or evidence of Mother Nature,” he said.
The backup was caused by a large blockage containing grease, plastic bags and commercial-grade paper towels that likely came from the Pine Mountain Lake clubhouse, Mello said. He said GCSD officials “followed that line back upstream,” and it led directly to the clubhouse.

Multiple manholes downstream from the facility also showed grease buildup, he said.

“We’re going to be very proactive with the management of Pine Mountain Lake regarding their discharge and their grease traps into the system. We know those are not likely coming from the residents,” Mello said.

This month’s spill was the latest in a series of overflows in the Grove-land system in recent years, including spills reported in June and July during Mello’s first two weeks as general manager. The district is also facing a possible fine of more than $1 million related to larger spills in August 2010 and March 2011.

The state water board has accused the district of failing to properly report the earlier spills and their sizes. The two parties are currently working out a possible settlement, and water board officials previously said the fine could come down if the district improves its systems and policies.

Julie Macedo, a staff attorney for the board’s enforcement department, said last week that the discussions are “continuing,” but she also said she couldn’t discuss further details. Mello also confirmed last week that settlement talks are ongoing.

Mello pointed to this month’s overflow as an example of an incident that would be difficult for district staff to prevent. He said they could have probably “inspected that manhole every six months” for years, and the clog could still occur.

“There are certain things that happened that are completely out of our control,” he said.