|
CIWMB’s Solid Waste Information System (SWIS) number: 23-AA-0018
Site Information per
Landfill Facility Compliance Study (Task 2)
Information Source: Owner/Operator—Mendocino County Department
of Transportation, Solid Waste Division
Telephone conversation: April 2, 2004
Since January 1998, the owner has not been required to conduct a
corrective action program (CAP) or come under a water-related cleanup
and abatement Order (CAO). In the mid-1990s, the owner constructed a
groundwater interceptor trench up-gradient of the landfill. However, the
trench was found to be ineffective at lowering the water table at the
site and its use was discontinued.
Based on site experience, ceasing landfill operations has been
beneficial in terms of being in compliance and protecting the
environment; without the active face with exposed waste, compliance has
been improved. Currently, the owner is working toward achieving final
closure of the site. A final closure plan was submitted in 2003 and the
owner is awaiting comments from the regulating agencies. With the
current schedule and funding, construction of the final cover will not
occur until after the 2004 construction season.
Based on the owner’s experience at this site, the process required to
obtain revised waste discharge requirements (WDR) and an approved final
closure plan has been difficult. The process has been going on for over
a decade and revised WDRs have not been issued.
The owner was not familiar with the reasons for the areas of concern (AOC)
reported by the enforcement agency (EA) in 1998 and 2000 for leachate
control issues.
The interviewee noted that there are no groundwater-, landfill gas-, or
surface water-related regulations that have been too confusing (or
contradictory) to be implemented or enforced at this site. However, the
owner noted that compliance with the stormwater monitoring requirements
is difficult. The owner is required to sample stormwater within 30
minutes of the first off-site discharge. The site is inactive and
remote. It is a two-hour drive for the owner to reach the site for a
sampling event. Therefore, the requirement is impractical to complete.
Information Source: North Coast Regional Water Quality Control Board
Telephone conversation: April 8, 2004
E-mail response: May 6, 2004
This site is a small, rural, unlined facility, which no longer receives
waste, is closed under intermediate-cover, and is awaiting final closure
construction. An evaluation monitoring program (EMP) has been ongoing
following low-level detections in groundwater monitoring wells. These
impacts are expected to improve after the final cover is completed and
infiltration is minimized. No water-related CAO has been issued. Final
construction closure is planned within the next few years. Any
outstanding groundwater issues will be discussed as part of the closure
WDR update, which is planned for the near future.
Some mineralization and spring activity have also been identified below
the landfill. A groundwater cut-off trench was constructed up-gradient
of the landfill to divert groundwater to surface water. However, the
owner indicates that this is no longer in use.
The owner has been under a stipulated order from the CIWMB for
insufficient closure funding and overdue submittal of closure plans.
Recently, the owner has made provisions to provide for closure funds.
However, until sufficient funds are set aside, the owner will not be in
a position to close the site. Another issue affecting the timing of
closure is the availability of borrow soils. The owner has recently
constructed a transfer station in the former borrow area. To provide for
borrow soils near the site, the owner has indicated an intention to file
a timber harvest plan, go through the California Environmental Quality
Act (CEQA) process, and then complete the timber harvest in order to
establish a borrow area available for closure materials.
In October 2003, the owner submitted draft closure plans to the regional
water quality control board. Earlier versions of the closure plan had
called for clean closure; the current draft closure plan proposes a
hybrid final cover with synthetics and clay. In addition, because the
site is located within the San Andreas fault zone, it is potentially
subject to high seismic acceleration, and the slope stability analyses
are especially complex. Thus, Department of Water Resources personnel
with extensive experience in slope stability issues are currently
reviewing the slope stability analysis in the closure plan, at the
behest of the RWQCB.
At this time, the RWQCB has not received a complete joint technical
document (JTD) to begin the WDR update. The RWQCB is currently working
with the owner on the closure plans, which are a critical component of
the JTD.
Information Source: Enforcement Agency—Mendocino County Public Health
Department, Division of Environmental Health
Telephone conversation: April 9, 2004
E-mail response: April 28, 2004
There have been no gas-related compliance issues at this site since the
beginning of the study period (January 1, 1998). The enforcement agency
(EA) has issued several areas of concern (AOCs) for not meeting minimum
landfill standards for leachate control in 1998 and 2000. The AOCs were
issued to improve leachate control at the active face/tipping area.
Issues that occurred include a clogged leachate pipe, resulting in
ponding of leachate adjacent to the tipping area, and leaks in the berm
that directed leachate into the leachate collection system (LCS) pipe
for transport to the LCS storage tanks. In each instance, the AOC was
adequately addressed by the operator.
Information Source: Mendocino County Air Quality Management District
The Mendocino County Air Quality Management District (AQMD) has not
issued any permits, requested monitoring and reporting, conducted any
inspections, or issued any violations for this site and so was not
interviewed. As such, the Mendocino County AQMD was not initially
contacted, but was later contacted several times for review and comment
of the in-depth information as it was being developed.
List of Landfills
|
