|
CIWMB’s Solid Waste Information System (SWIS) number: 37-AA-0005
Site Information per
Landfill Facility Compliance Study (Task 2)
Information Source: Owner/Operator—Ramona Landfill, Inc.
E-mail response: April 9, 2004
Groundwater monitoring was initiated at the Ramona Landfill following
the installation of six shallow groundwater monitoring wells (RAGW-1
through RAGW-5 and RAGW-7) by the county in January 1986. Until about
1990, groundwater samples from these wells were analyzed only for
general water quality parameters. In 1987, Phillips-Reynolds, Inc. (PRI)
installed a shallow test well and two nested observation wells (piezometers)
to evaluate the suitability of the northern 80-acre parcel as a
potential expansion area. As part of that evaluation, PRI noted that
concentrations of several inorganic monitoring parameters were elevated
in down-gradient monitoring wells relative to up-gradient monitoring
well RAGW-7 and attributed this condition, in part, to landfill impacts
to groundwater. In 1990, the county initiated work on the facility’s solid waste
assessment test (SWAT) as mandated by the State of California Water Code
(IT Corporation, 1992a). As part of the SWAT investigation, the county’s
consultant, IT Corporation, installed one additional down-gradient
monitoring well (ITRA-1) and conducted periodic testing of on-site
monitoring wells for inorganic and organic monitoring parameters. The
results of the SWAT testing indicated the presence of several volatile
organic compounds (VOC) and inorganic compounds in site monitoring wells
which they attributed to landfill impacts. VOCs were also detected in an
off-site water supply well. Based on the results of the earlier SWAT investigation, the county
initiated a voluntary evaluation monitoring program (EMP). The initial
phase of the EMP was conducted by the county during July 1992 and
included the installation of two additional onsite monitoring wells
(ITRA-2, ITRA-5) and two offsite monitoring wells (ITRA-6 and ITRA-7).
The county also conducted a vadose zone investigation that indicated
that landfill gas from the Ramona Landfill was migrating offsite. Based on the results of the initial EMP investigations, additional site
investigation activities were initiated in late 1992 to assess the
nature and extent of groundwater impacts at the Ramona Landfill. The
site investigation activities included aquifer testing of on-site
monitoring wells, surface geophysics, sampling and analysis of
monitoring well headspace gases, and performance of a soil gas survey
for an area of potential off-site contamination south of the landfill
(the “Lucas Property”). The investigation included an inventory of
off-site water supply in the vicinity of the landfill. Samples from
several of these off-site water supply wells were found to contain low
concentrations of select VOCs. Based on the results of earlier site assessment work, the county
expanded the ongoing groundwater monitoring program for the Ramona
Landfill to include several off-site monitoring wells and water supply
wells. From 1991 to 1994, two additional off-site monitoring wells
(ITRA-6 and ITRA-7) and eight privately-owned off-site water supply
wells (OFRA-1 through OFRA-7, and OFRA-10) were added to the routine
monitoring program conducted by the county for the Ramona Landfill.
Additional off-site monitoring points have subsequently been added to
the off-site monitoring program. On March 7, 1997, the regional water quality control board (RWQCB)
adopted Cleanup and Abatement Order No. 97-17 for the site. CAO No.
97-17 formalized the EMP and interim corrective action activities which
had been previously performed by the county on a voluntary basis. On October 15, 1997, the waste discharge requirements for the Ramona
Landfill were formally revised to reflect the transfer of ownership for
the facility from the County to Ramona Landfill, Inc. (RLI) (RWQCB Order
No. 70-R14). As part of the property transfer, remediation and
monitoring responsibilities were split between the two parties with RLI
assuming responsibility for on-site areas and the county assuming
responsibility for off-site areas. Since the divestiture, all monitoring
and site investigations for the Ramona Landfill’s on-site and off-site
areas have been conducted separately. With its divestiture of the Ramona Landfill, the county’s subsequent
site investigation and monitoring activities have generally focused on
the area south of the landfill. Since 1997, the county has continued to
expand the scope of the routine “off-site” monitoring program and as of
March 2002, the county was monitoring up to 32 offsite wells on a
semi-annual basis. In 1997, the county initiated a Phase II EMP at the off-site area south
of the Ramona Landfill to evaluate groundwater flow characteristics and
paths in the area south of the landfill. The EMP investigations included
aerial photo interpretation, geologic mapping, surface geophysics, depth
discrete groundwater sampling, exploratory trenching, and evaluation of
vertical flow characteristics in existing monitoring wells and water
supply wells. Between April 1999 and January 2000, the county installed
a series of additional groundwater monitoring wells. In April 1999, the
county installed four groundwater monitoring wells on county-owned
property immediately down-gradient (south) of the Ramona Landfill.
ITRA-8, ITRA-9, and ITRA-10 are shallow groundwater wells that are
screened predominantly within saturated portions of the weathered
bedrock. ITRA-11 is a deep monitoring well (screened from about 200 to
230 feet below ground surface (bgs)) located adjacent to monitoring well
ITRA-9.It was installed primarily to provide information regarding the
potential hydraulic connection between the weathered and unweathered
groundwater zones. During January 2002, the county installed two
additional sets of nested monitoring wells in the area south of the
Ramona Landfill. These two sets of nested monitoring wells are located
approximately 1,200 feet south (RAMW-4 and -5) and southeast (RAMW-1,
-2, and -3) of the site. Since its acquisition of the Ramona Landfill, RLI has conducted
substantial investigation of groundwater flow characteristics of the
“on-site area” and of potential remedial measures. In 1998, RLI
conducted a detailed evaluation of the groundwater and landfill gas (LFG)
extraction systems at the Ramona Landfill. In its report of findings,
Golder Associates concluded that majority of the VOCs detected in
groundwater from site monitoring wells were likely the result of LFG
impacts to groundwater and recommended that a series of LFG system
upgrades be performed to control the source of the VOCs. During January 1999, RLI conducted a detailed geophysical survey of
subsurface conductions beneath the site (Golder Associates, 1999). As
part of this project, Golder Associates utilized very low frequency (VLF)
Resistivity Imaging to investigate the depth and degree of saturation of
the weathered bedrock zone along the site’s southern and eastern
boundaries. The results of the investigation indicate that the depth of
the weathered bedrock in these areas is highly variable. During December 1999, RLI installed an exploratory test well and three
associated piezometers along the southern boundary of the Ramona
Landfill. The test well and associated piezometers were installed to
facilitate the completion of aquifer testing in this area. Aquifer
testing was conducted during June 2000 and results were submitted in
draft form to RLI in July 2001. During March 2000, RLI conducted a limited evaluation of VOC
concentrations in groundwater since the startup of the LFG extraction
system at the site. Based on VOC concentration trends from the four
on-site groundwater extraction wells, it was concluded that
concentrations of VOCs in these extraction wells had decreased since the
LFG system operation was improved. As part of the corrective action for the site, monitoring activities as
described above are ongoing. Since 2002, RLI has installed additional
gas wells and upgrades to the landfill gas management system, in order
to reduce the migration of landfill gas from the old portion of the
landfill into groundwater. Groundwater contaminant levels are trending
slightly lower. It is the owner’s experience from this site that an effective gas
collection system, operating 24 hours a day, is instrumental to avoiding
and resolving corrective action situations with respect to groundwater.
The owner is not aware of any landfill gas-related areas of concern (AOC)
or violations being issued to the site since the beginning of the study
period (January 1, 1998). There have been no issues related to leachate control at the site. AOCs
were issued in September 2002, October 2002, and April 2003 for standing
surface water on the landfill top deck. An NOV was issued in February
2004 for drainage/erosion control relative to erosion of cover soil. The air pollution control district (APCD) issued an NOV in March 2003
for a landfill gas leak from a gas collection system due to a crack in
the blower motor housing at the flare station. It has been the owner’s
experience at this site that APCD regulations related to landfill gas
control, monitoring, and reporting are not well-tailored to the
operation of a landfill. There are a number of redundant and confusing
reporting requirements, particularly those resulting from Title V‡
requirements.
Information Source: Regional Water Quality Control Board, San Diego
Regionn
E-mail responses: March 19, 2004, March 26, 2004, and April 27, 2004
The Ramona Landfill was issued Cleanup and Abatement Order No. 97-17 on
March 7, 1997. This CAO97-17 noted groundwater quality impairment due to
the discharge of VOCs from the Ramona Landfill. The CAO required the
County of San Diego to implement an EMP and subsequently required the
development and implementation of a corrective action program (CAP) for
the impacted groundwater. The County of San Diego submitted two technical reports regarding the
groundwater quality for the Ramona Landfill. The first technical
report—the solid waste assessment test, dated August 1992—confirmed
leakage from the Ramona Landfill. The second technical report, entitled
“Ramona Site Investigation,” dated February 1993, included a
comprehensive program of on- and off-site groundwater sampling and
testing to characterize local groundwater quality. The purpose of the
site investigation was to define the nature and extent of groundwater
contamination down-gradient of the Ramona Landfill. The Ramona site
investigation suggested that VOCs and elevated chloride concentrations
in a domestic well south of the landfill boundary were a result of
leachate migration from the Ramona Landfill. The CAO was written based
on the results of the SWAT and Ramona site investigation. The purpose of
the CAO was to formalize an existing corrective action program being
conducted by the discharger. The CAP is ongoing. Allied Waste (the owner since October 1997) has been
pumping the groundwater at the southern boundary of the landfill. In
addition, a landfill gas system was installed in 1996.. The County of San Diego, under CAO 97-17, continues to monitor wells
down-gradient of the landfill to determine horizontal and vertical
extent of contamination. This site was unlined until approximately 1998. The groundwater impacts
noted in the SWAT were probably the result of landfill gas from the
unlined portion of the landfill. This site did not have a landfill gas
collection system until 1996.. The RWQCB finds that the federal regulations, (Title 40, Code of Federal
Regulations, Part 258) for groundwater monitoring are confusing and do
not mesh well with the requirements contained in Title 27 of the
California Code or Regulations. At this site, the timing of submittal of
reports has been hard to comply with. The EMP for the off-site migration
from the Ramona Landfill has been conducted for years. However, the
evaluation of the plume is complicated by inconsistent sampling of the
wells down-gradient of the landfill (for example, sometimes well owners
would change their mind regarding access/sampling of their wells), so
that it is difficult to comply with the Title 27 timing requirements. The RWQCB is planning to update the CAO to include Ramona Landfill Inc.
as a responsible party. The revised CAO will include findings to reflect
the current status of delineation of the plume from the Ramona Landfill.
Information Source: Enforcement Agency—County of San Diego, Department
of Environmental Health
E-mail response: March 23, 2004
Landfill gas monitoring wells were installed at the Ramona Landfill in
late 1993 to meet the new criteria set forth in the federal Subtitle D§
regulations. A landfill gas control system was installed at the
beginning of August 1994 and completed in late 1995 (work ceased for a
few months due to funding problems and alleged irregularities with the
contract bidding process). The landfill gas control system was upgraded
in August 1997 with additions made to the header line and extraction
wells. In September 1997, two additional monitoring wells were
installed. In October 1997, the county sold the Ramona Landfill to
Allied Waste Industries, Inc. In March 1998, new gas extraction wells
and monitoring wells were installed, which led to the facility’s removal
from the State inventory of solid waste facilities violating State
minimum standards in June 1998. The gas control system continued to be
fine-tuned and improvements made at the landfill gas flare until early
1999. Since the completion of this work in January 1999, the EA has not
issued any landfill gas violation or AOCs. The EA worked successfully
with the owners (both the county and Allied Waste, due to the sale of
the landfill during this period) to voluntarily install a system to
correct the landfill gas problem. The EA believes that landfill gas issues at this site can be corrected
with minor fine-tuning of existing control systems. However, some
landfill gas issues are difficult to diagnosis and equally difficult to
mitigate. These take time and are sometimes corrected only by trial and
error. It would be helpful to have more technical support from the CIWMB
staff, as well as to have the CIWMB staff be more open to new
technologies and more innovative ideas for correction of long-term
landfill gas problems.. The EA issued a violation for drainage (Title 27 of the California Code
of Regulations [27 CCR], Section 20510) for a blown-out slope on
February 24, 2004. The EA also issued an AOC for erosion (27 CCR,
Section 20700) of the intermediate cover on a bench road on May 20, 2003
and June 19, 2003, and an AOC for drainage (27 CCR, Section 20820) for
runoff going off-site and not into the sedimentation pond on Oct. 3,
2002. The owner has installed sandbags approximately every 50 feet along the
bench roads and hay rolls (wattles) and sandbags have been used on the
top deck of the unlined portion of the landfill to slow the water
runoff. A larger sedimentation pond on the south/east side of the
landfill was created in March 2002. These additional protection measures
may have provided additional protection of the environment..
Information Source: San Diego County Air Pollution Control District
E-mail response: March 23, 2004 and May 12, 2004
The San Diego County Air Pollution Control District has issued three
notices of violation (NOV) between January 1, 1998 and April 1, 2003.
The following summary of the NOVs was developed by the contractor for
the Landfill Facility Compliance Study from files provided by the APCD.
NOV # 206631 (March 20, 1998): Failing to maintain in good working order
landfill gas collection and flare system by allowing emission of
landfill gas in excess of 500 parts per million by volume (ppmv)
measured as methane immediately above landfill surface. Failing to
maintain in good working order landfill gas collection and flare system,
specifically by landfill gas emissions between 500 and 10,000 ppmv
measured as methane next to extraction well #26. Landfill gas emissions
leaking from flame arrestor measured between 1,375 and 10,000 ppmv by
volume measured as methane. Response: In letter dated March 27, 1998, the owner stated that on March
23, 1998, a leak was repaired in the flame arrestor and additional soil
placed around extraction well #26 to reduce odors.. NOV # 210030 (May 3, 2000): Allowing the release of odors from the
condensate tank located inside the flare station enclosure,
Specifically, the tank had two open access holes, each approximately 2
inches in diameter, from which where odors were released. Response: A letter dated May 10, 2000, states two openings were capped
on May 3, 2000. NOV # 213437 (March 21, 2003): Landfill gas collection system had
emission from a crack in the casing in the motor house of the
easternmost blower (blower #2) at the blower/flare station on-site. The
leak measured in excess of 5,000 ppmv measured as methane at ½ inch from
the fissure. Response: In a letter dated March 28, 2003, the owner stated the cracked
blower had been sealed off from the system, and the blower was taken off
line. The owner was removing it and sending it to the manufacturer to
determine the cause of the crack, since it did not look impact-related.
Also, the owner would include inspection for cracks in the inspection
program of the LFG collection system.
†Additional
background information was available for Ramona Landfill, based on the
relationship of the contractor performing the interviews with the previous
owner of the site (County of San Diego). A corrective action program (CAP)
was required, and a clean-up and abatement order (CAO) was issued to the
county prior to the sale of the property to the current owner (Ramona
Landfill, Inc.) in November 1997. The county is the party listed on the CAO.
The basis for the CAP and CAO was the detection of VOCs in groundwater
samples from down-gradient monitoring wells. A corrective action was
selected based on the results of a site assessment and the environmental
monitoring program. The corrective action consists of a groundwater
extraction system, an LFG extraction system, a groundwater monitoring
program, a moratorium on well development, a water supply contingency plan,
and acquisition of buffer properties adjacent to the landfill. The
groundwater extraction system became operational in 1993. The LFG extraction
and flare system became operational in 1997. Adjacent properties were
acquired from 1993 to 2000. The County of San Diego believes that this
multi-faceted corrective action is proving to be effective: groundwater
quality has improved in the on-site wells, and improvements, while not
documented, are anticipated for the off-site wells.
‡Title V of the Clean Air Act
(Title 42, U.S. Code, section 7401 et seq.). Title 40, Part 70 of the Code
of Federal Regulations provides for the establishment of comprehensive state
air quality permitting systems consistent with the requirements of Title V.
These regulations define the minimum elements required by the Clean Air Act
for state operating permit programs and the corresponding standards and
procedures by which U.S. EPA will approve, oversee, and withdraw approval of
state operating permit programs.
§Also
known as Subtitle D of the Resource Conservation and Recovery Act, with
regulations found in Title 40, Part 258 of the Code of Federal Regulations
(40 CFR, Part 258).
List of Landfills
|
