Marine Corps Air Station Miramar

IRP Site 1 is located in the central part of MCAS Miramar and consists of six non-contiguous areas, including the existing fuel farm, that are identified as sites 1A through 1F. Waste petroleum, oils, lubricants, and tank bottom sludges were sprayed on vegetated areas and bare soil for weed and dust control from the early 1940s through 1975. The majority of the wastes were disposed of at the fuel farm. Sandblast grit used for cleaning the inside of gasoline storage tank was reportedly deposited on the ground. Subsequent studies investigated the sub-sites and, at some of the sub-sites, significant detections of petroleum hydrocarbons were measured.

The first investigation at IR Site 1 was reported in a 1984 initial assessment study, a confirmation study in 1987, and a site inspection at Site 1C in 2005. In preparation for construction of a new fuel farm immediately to the west of Site 1C in 2006, soils with elevated concentrations of total petroleum hydrocarbons and polychlorinated biphenyls were excavated and disposed of off-site. A 2007 final inspection report recommended no additional assessment of the shallow hydrocarbon-impacted soils in the area at the time.

In 2012, an engineering evaluation and cost analysis presented and evaluated removal action alternatives for sites 1A, 1B, 1D, and 1F. Soil samples collected from Site 1F did not contain contaminants above remedial goals, and the Regional Water Quality Control Board concurred in 2013 with the Navy’s recommendation for no further action at the site. Soil excavation, backfilling, and off-station disposal was the chosen remedial alternative for sites 1A, 1B, and 1D. Site 1A was excluded from the removal action because of potential impacts to vernal pools located on the site and the need for additional assessment. The removal action at sites 1B and 1D to excavate soils with elevated concentrations of contaminants was completed in 2015. Based on the results, Site 1D was designated for unrestricted reuse in 2016 by the Regional Water Quality Control Board.

An evaluation of the nature and extent of contamination at sites 1A, 1B, 1C, and 1E concluded that additional soil sampling was needed to support no further action at sites 1A and 1E. In May 2020, a data gap investigation was conducted to collected additional samples at sites 1A and 1E. Based on historical information and investigations, current physical conditions at the sites, and data gap investigation analytical results, the November 2020 data gap investigation report recommended no further action at sites 1A, 1B, 1C, and 1E. The Regional Water Quality Control Board concurred with the request for no further action and requested a record of decision to document the finding. IRP Site 1 site remains open, pending completion of the record of decision.

IRP Site 2 incorporates the creek bed and banks of Rose Creek, an ephemeral stream, and a portion of adjacent Rose Canyon slopes along a 100- to 300-foot-wide swath reaching from Miramar Way on the east to 1 mile west of Pless Road. During the 1940’s through the 1960’s, industrial materials were commonly discharged into Rose Canyon via storm drains. Concentrated wastes, including oils, greases, hydraulic fluid, fuels, solvents, paint thinners, plating wastewater, corrosive wastes, and beryllium dust were reportedly disposed of on this site.

Investigations at IRP Site 2 began in 1984 with an initial assessment study, followed by a confirmation study in 1987. A site inspection was conducted in 2015 to assess whether storm water outfalls that conveyed industrial effluent resulted in a release of chemicals of potential concern to IR Site 2. The site inspection report recommended an extended site inspection and baseline risk assessment to characterize the distribution of contaminants in soils at IR Site 2 and to ensure protection of human health and the environment.

The results of a 2017 extended site inspection confirmed and delineated contaminants across the site including naturally occurring arsenic, lead, mercury, manganese, cobalt, and selenium that exceeded base-wide background levels, and concentrations of pesticides, polychlorinated biphenyls, and polycyclic aromatic hydrocarbon detected in the soil of Rose Canyon Creek that exceed human health and ecological screening levels. Recommendations for further evaluation of naturally occurring metals at the site were provided.

In 2019, a work plan for background study limited data gap investigation was developed to create a representative background data set for metals concentrations and to further delineate the extent of other contaminants of concern at IRP Site 2. The results of the study will support decision making for any future removal action needed at IRP Site 2. Fieldwork for the study was completed in 2020, and an engineering evaluation/cost analysis for a non-time critical removal action is being prepared for the site. The site remains open.

IRP Site 3 is a fish pond located just south of Rose Canyon, approximate one half mile north of the departure end of runway 25R. The pond was constructed between 1951 and 1952 to provide recreation and fishing areas for the air station. IRP Site 3 was located at the mouth of a canyon which received untreated runoff between 1952 and 1976 from air station runways, aircraft parking aprons, and aircraft fueling stations. The untreated runoff contained jet fuels, leaded aviation gasoline, and wastewater from aircraft washing operations. Investigation at IRP Site 3 began in 1984 with an initial assessment study, and IRP Site 3 was closed with no further action required following the completion of the site inspection in 1998.

The drill fields at the area now identified as IRP Site 4 were used for training fire fighters in the suppression of fuel and oil fires. Between 1958 and 1981, waste material, primarily fuel, was poured directly onto the ground then ignited. Investigation at IRP Site 4 began in 1984 with an initial assessment study. Following the removal of heavy metals and fuel-contaminated soils at this site in June and July 2005, this site was closed with no further action required.

IRP Site 5 is located just south of the main runway for the airfield at MCAS Miramar and was used as the air station’s main refuse disposal location. Between 1940 and 1974, solid refuse and liquid wastes were staged, disposed of, and burned. Waste materials included paints, pesticides, solvents, and spent lead batteries.

Investigations at IRP Site 5 began in 1984 with an initial assessment study. Soil and sediment samples were collected as part of a confirmation study in 1987. No groundwater samples were collected during the confirmation study because groundwater was not encountered before difficult conditions stopped drilling progress past 122 feet below ground surface.

A waste removal action was conducted in 2004. Numerous drums, containers, automobile parts, scrap metal, and assorted debris were cleaned up and disposed of. A site inspection was completed in 2006, resulting in the finding that there are large fill areas along the canyon at the end of the runway, including a horseshoe shape around the burn area, where wastes were disposed of in surface disposal areas. In addition, overshot from a local skeet range known as IRP Site 19 was observed in the area. Contamination was further delineated during a 2008 remedial investigation and feasibility study.

A 2012 action memorandum documenting the Navy’s decision to undertake an interim time critical removal action at IRP Site 5 presented the selected remedy for soil, which consisted of a multilayer soil cover, engineering controls, institutional controls, land use controls, and a monitoring and maintenance program. The removal action was performed in two phases in 2012 and 2013, and the multi-layer soil cover was completed in 2014. Portions of IRP Site 5 were re-designated as IR Site 20 in 2015. Long-term monitoring and maintenance of IRP Site 5 began in 2016 and are ongoing. The site is currently open.

IRP Site 6 was operated by the City of San Diego between 1959 and 1983 for refuse disposal. It is located south of runways at what was known until 1996 as Naval Air Station Miramar, now MCAS Miramar. The site received drummed liquid waste from the Naval Air Station Miramar Corrosion Control Center between 1972 and 1983, including paint, paint thinner, paint stripper, non-chlorinated solvents, and corrosive waste. Investigations at IRP Site 6 began in 1984 with an initial assessment study. A cap was placed on the landfill and IRP Site 6 was closed under CERCLA in May 1997 with no further action required by the California Department of Toxic Substances Control.

IRP Site 7 is a 446-acre area located just south of San Clemente Canyon on West Miramar. It was leased to the City of San Diego in 1959 for the operation of a sanitary landfill. South Miramar Landfill was operated by the City of San Diego until 1972 and may have received industrial wastes during this time, including paints, oils, and strong acids. Investigations at IRP Site 7 began in 1984 with an initial assessment study. A cap was placed on the landfill and in May 1997, the Department of Toxic Substances Control closed IR Site 7 with no further action required under CERCLA.

IRP Site 8 is located at the southwest end of the old Camp Elliott barracks north of Murphy Canyon. The Old Camp Elliott Heating Plant was built in the 1940’s and operated until 1960. Asbestos insulation that coated the plant’s eight boiler tanks and ancillary piping deteriorated and fell to the floor creating an asbestos dust hazard. Investigations at IRP Site 8 began in 1984 with an initial assessment study. The deteriorated materials and affected soils were removed and properly disposed of during site cleanup in 1985 in conjunction with the demolition of the plant. Following a final site inspection, regulatory officials closed IRP Site 8 in April 1997 with no further action required.

IRP Site 9 is located north of Murphy Canyon and consists of former munitions ranges and impact areas for live fire training east of Interstate 15 identified in a 1984 initial assessment study. These areas were described as the Figure-8 gunnery range, and the Murphy Canyon, Fortuna Mountain, and Sycamore Canyon impact areas. The study recommended that Navy Explosives Ordnance Disposal personnel perform a removal sweep for unexploded ordnance potentially present in the impact areas. It was determined that the areas that comprise IRP Site 9 are operational ranges at MCAS Miramar and the potential for the presence and ongoing release of unexploded ordnance remains. IRP Site 9 was removed from the ERP program due to current operational requirements. If the use of these areas for active training should cease in the future, then the site will be reinstated into the ERP, likely under the MRP.

IRP Site 10 is located in Sycamore Canyon in the northeastern corner of East Miramar, approximately 5 miles east of Interstate 15. The facility was established in 1955 as a high-security testing area for the Atlas Missile program, which was run by General Dynamics under National Aeronautics and Space Administration and the United State Air Force. The facility was transferred from the Navy to the United States Air Force In 1960 and subsequently National Aeronautics and Space Administration. In 1970, the site was declared excess to National Aeronautics and Space Administration and was restored in 1971 to Navy custody.

Following closure of the facility, the site was vandalized and several electrical transformers containing polychlorinated biphenyls were damaged. In 1982, polychlorinated biphenyl contaminated materials were excavated, removed, and disposed of offsite. IRP Site 10 was included in a 1984 initial assessment study that concluded that no significant contamination resulted from missile engine testing at the site. An asbestos survey was conducted at the site in 1994, followed by additional sampling of soils and surveys of test stand areas.

A 2006 site inspection confirmed polychlorinated biphenyl contamination in soil at the site and found polychlorinated biphenyls contamination on a nearby access road to an explosive ordnance disposal site. An engineering evaluation and cost analysis was prepared to address alternatives for remediating contamination at IRP Site 10. A 2010 action memorandum documented the selected alternative, which included excavation and off-site disposal of contaminated soil. A limited removal action was conducted in 2010 to remove polychlorinated biphenyl impacted soil from structures adjacent to the facility and along the explosive ordnance disposal road.

An additional removal action was completed in 2015 to remove the polychlorinated biphenyl sediment and debris from around and inside a blockhouse structure at the facility. A remedial investigation work plan addendum was finalized in February 2020 with the plan to fully characterize the remaining contamination at the site. The remedial investigation fieldwork was completed in 2020 and the remedial investigation report is underway. The site is currently open.

IRP Site 11 is a drainage ditch located at the intersection of Miramar Way and Nomad Road. Soil along this natural drainage ditch received contamination when an oil/water separator malfunctioned and clogged. The oil/water separator was associated with the Auto Maintenance Facility, the Truck Maintenance Facility, and Pesticide Mixing and Storage Facility. Contaminants of potential concern included petroleum hydrocarbons. IRP Site 11 was cleaned up in 1995 and closed in 1996 with a no further action required letter from the Regional Water Quality Control Board.

IRP Site 12 is a drainage ditch located southwest of the Navy Exchange Main Gas Station. This natural drainage ditch received contaminated runoff resulting from a clogged oil/water separator located at the Auto Hobby Shop. Contaminants of potential concern included petroleum hydrocarbons. IRP Site 12 Site was cleaned up in 1995 and was closed in 1996 with a no further action required letter from the Regional Water Quality Control Board.

IRP Site 13 is a drainage ditch located at the Aviation Intermediate Maintenance Department. Soils along the natural drainage ditch were contaminated following a clog in an oil/water separator. Wastes were a result of aircraft engine testing, solvent cleaning of engine components, and engine repair and maintenance operations. Contaminants of potential concern included petroleum hydrocarbons. IRP Site 13 was cleaned up in 1995 and was closed in 1996 with a no further action required letter from the Regional Water Quality Control Board.

IRP Site 14 is a drainage ditch located near Hangar 6 on MCAS Miramar’s flight line. Contaminants of potential concern included petroleum hydrocarbons and lead. Contaminated soils were removed from the site in 1996. Following a determination that any residual contamination did pose no significant threat to groundwater and surface water, IRP Site 14 was closed in 1996 with a no further action required letter from the Regional Water Quality Control Board.

IRP Site 15 is located adjacent to Building 238 and was used as a hazardous waste storage area until 1992. Soil contamination resulted from spills associated with storage of waste fuels, solvent rags, and waste oils. The resulting contaminants of potential concern included petroleum, oil, and lubricants, and total recoverable petroleum hydrocarbons. A site inspection to assess the contamination was completed in 2012. A 2014 extended site inspection resulted in a recommendation for no further action at IRP Site 15. Concurrence was received from the Regional Water Quality Control Board in 2014 and the site was closed.

IRP Site 16 is adjacent to the K212 Boiler Plant formerly known as Building 7212. In 1996, seven underground storage tanks were removed from the east, north, and south sides of Building 7212. During the removal of an underground storage tank on the northeast side of Building 7212, evidence was found of a small mercury release. Based on the localized area of observed soil contamination and the type of equipment historically used at the steam plant, the source of the mercury was mostly small switches damaged when they were removed during the boiler plant’s decommissioning, which was occurring at the time of the underground storage tank removals.

A new building, 7214, was constructed in the southern portion of IRP Site 16 between 2009 and 2010. A site inspection to assess the contamination was completed in 2014. Analysis of soil samples detected contaminants at levels that do not pose a threat to human health or the environment. No further action was recommended for IRP Site 16. Concurrence was received from the Regional Water Quality Control Board in 2016 and the site was closed.

IRP Site 17 is located at Building B380 which was constructed in 1959 and used as a photo imaging laboratory. Leaking sumps beneath the building contaminated soil in the immediate area with photo processing chemicals. Contaminants of potential concern include metals and semivolatile organic compounds. The site was added to the IRP in 1996. Following analysis of soil samples collected during a preliminary site investigation and an assessment of the potential risk associated with impacted soils under the building, the Regional Water Quality Control Board concurred with the Navy’s request for no further action in a letter, and IRP Site 17 was closed in November 1998.

IRP Site 19 is an approximately 43-acre site inclusive of a skeet range and portions of San Clemente Canyon. The site consists of the approximately 30 acre former San Diego Shotgun Sport Association lease area and the approximately 13 acre overshot area. Lead shot deposits have been observed in both areas. Additionally, undocumented fill material from sites of demolished power plants was used during construction of the western portion of the site.

A 2010 preliminary assessment and site inspection produced analytical results indicating high concentrations of metals in the soils at the site. Based on these findings, the site was added to the IRP in 2011 for further evaluation. An interim removal action was completed in 2017 to implement erosion control measures and to assess the feasibility of removing surface lead and polycyclic aromatic hydrocarbon contamination.

Evidence of contamination caused by overshot from the adjacent MRS 10 was found at IRP Site 19. Based on the similarities of the contamination and the evidence of cross contamination between the sites, MRS 10 was transferred from the MRP program and placed within the IRP Site 19 boundary, resulting in the closure of MRS 10.

A 2020 action memorandum documented the decision to undertake a removal action for bulk lead shot and clay target fragments in soil associated with former shotgun shooting activities at IRP Site 19. The final work plan for the removal action was published in June 2020. The removal action was conducted in 2020 and 2021 and the site remains open.

IRP Site 20 is located at the west-central portion of MCAS Miramar within the northeast trending San Clemente Canyon, and southeast of the main air station runways. The site is currently vacant and unoccupied. There are no plans for development because of the site’s location and an ecologically sensitive area hosting an ephemeral steam and vernal pools.

IRP Site 20, the San Clemente Disposal Area, was part of IRP Site 5, the Former San Clemente Canyon Landfill, prior to 2015. IRP Site 5 still comprises the main waste area of the original IRP Site 5, where an engineered cap was constructed in 2012 as part of an interim time critical removal action. This capped main waste area, still referred to as IRP Site 5, is currently undergoing long-term maintenance and monitoring.

The remaining portions of the original IRP Site 5 that surround the capped main waste area are now referred to as IRP Site 20. Although much of the debris was excavated and removed during the former IRP Site 5 interim time critical removal action, small amounts of debris and trash remain on the surface and in the subsurface at IRP Site 20. In addition, overshot from a local skeet range, IR Site 19, was observed in the area.

A supplemental remedial investigation specific to IRP Site 20 was initiated in 2016 to fully characterize contamination. Elevated levels of metals and polychlorinated biphenyls were detected in soils and sediments. A 2017 remedial alternatives analysis report evaluated options for remedial action, and in 2020 a pilot study work plan was submitted and approved by the Regional Water Quality Board. The pilot study will evaluate whether removal of contaminated soil and sediment will reduce the potential for unacceptable human health and ecological risks identified in the in the supplemental RI. Pilot study fieldwork is underway as of 2021 and the site remains open.

IR Site 21, the former Camp Elliott, was an active military training site during World War II that was built during the 1930s and 1940s. Presumed asbestos-containing material, including pipe insulation and floor tile, has been observed on the ground surface within and immediately adjacent to some of the old building footprints. Some asbestos-containing material was left on-site after the demolition activities were completed. Based on site plans and aerial photographs, most of the demolition appears to have taken place during the late 1960s to early 1970s.

Soil sampling for asbestos and lead was conducted in 2017 at former Camp Elliott on behalf of MCAS Miramar by Naval Facilities Engineering Systems Command Southwest. Trace concentrations of asbestos were detected in surficial soil samples collected from 0 to 2 inches below ground surface. Presumed asbestos-containing materials were also sampled, and all contained asbestos at concentrations ranging from 4 percent to 30 percent. Lead was also detected in shallow surface soil samples. Following completion of the initial sampling, the site was entered into the ERP as IRP Site 21.

A time-critical removal action will be conducted for asbestos-containing material and potentially contaminated soil at IRP Site 21. Fieldwork for the removal action is expected to be completed in fall of 2021. The site is currently open.

Back to Top

MRS 1 comprises 30.4 acres in the approximate center of the air station and is bisected by Interstate-15. From approximately 1941 through 1943, the former Grenade Course was a historical range used for grenade and bayonet training. The configuration of the former grenade course included a western section used for grenade training and two eastern sections used for bayonet training. In October 2003, the Cedars Wildfire burned through the area east of Interstate-15, where the Grenade Course is located.

The former Grenade Course MRS was first subject to a limited-scope MRP investigation in 2007 when a preliminary assessment was conducted. Fieldwork conducted during a 2010 site inspection found no evidence of munitions and explosives of concern, although munitions debris was observed including one grenade handle and a possible smoke grenade packaging cap. The presence of nitrate in a “foxhole” sample collected during the field work led to the recommendation that a remedial investigation and feasibility study for munitions constituents were warranted to ensure that MRS 1 was clear of any potential hazards.

An extended site inspection was initiated in 2016 to further characterize the site. The final 2019 extended site inspection report recommended no further action at MRS 1, and the site was closed.

MRS 2 is in the central portion of MCAS Miramar north of the runway and includes approximately 29-acres. The northern end of the former outdoor shot gun sighting range fan extends to the edge of Rose Canyon. MRS 2 was used by servicemen at the former Naval Auxiliary Air Station Camp Kearny during the mid-1940s into the early 1950s. The former shotgun sighting range overlapped MRS 3, the former skeet range. Much of the area comprising MRS 2 has been developed, providing the air station with a flight operations and support area including Hangars 5 and 6, asphalt parking areas to the north of the hangars, and military support buildings containing offices surrounded by landscaping northeast of the hangers.

The former Shot Gun Range MRS was first subject to a limited-scope MRP investigation in 2007 when a preliminary assessment was conducted. Although historical uses indicated that incidental contaminants of concern were lead, arsenic, and polycyclic aromatic hydrocarbons, no munitions constituents or evidence of incidental contaminants of concern were observed. This was attributed to the current use and past ground disturbing and extensive construction activities that had occurred at the site. No further action was recommended and MRS 2 was closed in September 2007.

MRS 3 is in the central portion of MCAS Miramar north of the runway and includes approximately 29 acres. The northern end of the former outdoor skeet range fan extends to the ends of Rose Canyon. MRS 3 was used by servicemen at the Navy Auxiliary Air Station Camp Kearny during the mid-1940s into the early 1950s. The former skeet range overlapped MRS 2, the former shotgun sighting range. MRS 3 has been developed as a flight operations and support area within the fenced-in airfield portion of the installation, including Hangars 5 and 6, a concrete ramp leading to the hangars, and asphalt parking areas to the north of the hangars which provide a staging area for helicopters. Based on historical uses at MRS 3 incidental contaminants of concern were lead, arsenic, and polycyclic aromatic hydrocarbons.

The Former Skeet Range MRS was first subject to a limited-scope MRP investigation in 2007 when a preliminary assessment was conducted. Although historical uses indicated that incidental contaminants of concern were lead, arsenic, and polycyclic aromatic hydrocarbons, no munitions constituents or evidence of incidental contaminants of concern were observed. This was attributed to the current use and past ground disturbing and extensive construction activities that had occurred at the site. No further action was recommended and MRS 3 was closed in September 2007.

MRS 4 was a small arms range used by the San Diego Shotgun Sports Association. Because the range’s only use consisted of small arms, it was transferred into the IRP as IRP Site 19 once the range was no longer operational.

MRS 5 includes approximately 41.32-acres in the central portion of MCAS Miramar, northeast of the MCAS Miramar airfield, north of Boyington Road, and west of Kearney Villa Road. The former Skeet Range 1980 was a small arms range used for training between 1958 and 1980. MRS 5 featured four skeet-shooting fields in the western portion of the site and four trap-shooting fields in the eastern portion of the site. Direction of fire from both skeet and trap shooting fields was from south to north. The range has been inactive since 1980 and by 1996 natural vegetation covered the range completely.

The former Skeet Range 1980 MRS was first subject to a limited-scope MRP investigation in 2007 when a preliminary assessment was conducted. During a 2010 site inspection, munitions debris was observed and documented, including empty shotgun shells, shotgun shell pieces, areas of accumulated lead pellets from expended shotgun ammunition, and broken skeet fragments. No munitions and explosives of concern were identified at the former range. Munitions constituents were detected for metals associated with shotgun shell debris above human health project screening levels in surface soil samples collected at the site.

The site inspection report recommended that a remedial investigation and feasibility study be conducted for MRS 5, with a focus on munitions constituents. The remedial investigation began in 2016 and a soil removal was conducted at MRP 5 and documented in a 2019 soil removal report. The final remedial investigation and feasibility study reports were published in February 2020. A draft action memorandum supporting the Navy’s selection of a non-time-critical removal action alternative for bulk lead shot and clay target fragments in soil at MRS 5 is currently under review by the regulatory agencies. Implementation of the non-time-critical removal action is underway in 2021, and the site remains open.

MRS 6 consists of approximately 3.68 acres and is located in the northern portion of MCAS Miramar, northwest of the airfield and south of Miramar Road. Former Pistol Ranges 5, 6, and 7 were situated north of the former Camp Kearny boundary on the northern side of IRP Site 2, also known as Rose Canyon. The ranges were used between 1917 and 1920 and munitions usage was limited to small arms ammunition, specifically 0.45-caliber pistol ammunition. Since that time, the site has remained undeveloped.

The former Pistol Ranges 5-7 MRS was first subject to a limited-scope MRP investigation in 2007 when a preliminary assessment was conducted. Fieldwork conducted during a 2010 site inspection found no evidence of munitions and explosives of concern. Soil samples were collected to determine whether historical range activities had impacted soil at the site. Analyses confirmed that antimony, copper, lead, and zinc, metals associated with munitions, were present above installation background screening criteria for metals for soil and ecological project screening levels, and total lead concentrations were also above human health project screening levels.

The 2011 final site inspection report recommended no further action for munitions and explosives of concern and that a remedial investigation and feasibility study be undertaken with a focus on munitions constituents. Remedial investigation fieldwork was conducted at MRS 6 in September 2020. Following finalization and review of the results of the remedial investigation, the Navy will evaluate remedial alternatives. The site is currently open.

MRS 7 consists of approximately 12.4 acres and is located in the northwest portion of MCAS Miramar. The former firing lines for Rifle Ranges 2 and 3 are currently located within the current footprint of the installation’s Miramar Memorial Golf Course extending north into Miramar Road and commercial/industrial complexes north and outside of the installation boundary. The rifle ranges were probably operational between 1917 and 1920 and were used for small arms training, specifically 0.30-caliber rifle ammunition.

The former Rifle Ranges 2 and 3 MRS was first subject to a limited-scope MRP investigation in 2007 when a preliminary assessment was conducted. Fieldwork conducted during a 2010 site inspection found no evidence of munitions and explosives of concern. Soil samples were collected to determine whether historical range activities had impacted soil at the site. Results from analyses were within acceptable ranges for human health and ecological screening levels. The 2011 final site inspection report recommended no further action at MRS 7, and the site was closed with concurrence from the Department of Toxic Substances Controls.

MRS 8 is located on approximately 0.69 acres in the central portion of the installation, just south of Johnson Road in San Clemente Canyon. The former Pistol Range 12 was used between 1917 and 1920 and was used for small arms training, specifically 0.45-caliber pistol ammunition. The site is currently within the canyon drainage way and has become overgrown with vegetation.

The former Pistol Range 12 MRS was first subject to a limited-scope MRP investigation in 2007 when a preliminary assessment was conducted. Fieldwork conducted during a 2010 site inspection found no evidence of munitions and explosives of concern. Soil samples were collected to determine whether historical range activities had impacted soil at the site. Results from analyses determined that soils did not pose a risk to human health or the environment. The 2011 final site inspection report recommended no further action at MRS 8, and the site was closed with concurrence from the Department of Toxic Substances Controls.

MRS 9 is located along the southbound lanes of Interstate-15, on the eastern side of former Camp Kearny. Former Pistol Range 13 was used between 1917 and 1920 for small arms training, specifically employing the standard issue 0.45-caliber sidearm pistol.

The former Pistol Range 13 MRS was first subject to a limited-scope MRP investigation in 2007 when a preliminary assessment was conducted. Using historical aerial photographs and maps, geographical coordinates, and site reconnaissance, the site was found to be located beneath the northbound and southbound lanes of Interstate-52 at the State Route-52 West/Clairemont Mesa Boulevard off-ramp.

Because the former pistol range is contained within the interstate and the extensive ground disturbance from construction of the freeways in that area, it was determined that any residual munitions and explosives of concern or munitions constituents would have been removed during site preparation for the roadways and the interchange. No further action was recommended and MRS 9 was closed in November 2007.

MRS 10 consists of approximately 1.98 acres located south of the MCAS Miramar airfield on the northern side of San Clemente Canyon, north of the J. Harris Quarry facility. Former Pistol Ranges 9, 10, and 11 were used between 1917 and 1920 for small arms training, specifically employing the standard issue 0.45-caliber sidearm pistol. The site currently consists of undeveloped land, much of which is located within an “overshot” area where lead shot from an adjacent recreational skeet range would be anticipated to occur.

The former Pistol Ranges 9-11 MRS was first subject to a limited-scope MRP investigation in 2007 when a preliminary assessment was conducted. Fieldwork conducted during a 2010 site inspection focused on munitions constituents, specifically metals associated with munitions, and near surface soil samples were collected. Analyses confirmed that antimony, copper, lead, and zinc were present above installation background screening criteria for soil and ecological project screening levels. Total antimony and total lead concentrations were also above human health project screening levels. Based on these results, a remedial investigation and feasibility study for munitions constituents was recommended.

Because of similarities in contamination and evidence of cross contamination between the sites, MRS 10 was administratively transferred in 2016 from the MRP and placed within the IRP Site 19 boundary, the adjacent recreational skeet range, and MRS 10 was closed.

MRS 11 is located within the East Miramar Range Complex and is comprised of operational small arms ranges. Because the ranges are still operational, MRS 11 was removed from the MRP before the preliminary assessment phase.

MRS 12 consists of 3.48 acres located in the central part of the western portion of MCAS Miramar. The Navy extended the runway at the former US Naval Air Station San Diego, now MCAS Miramar, in the early 1940s. Because of proximity at the time of the dive-bombing target to the active runway, additional land north of the field was acquired for its relocation. Practice bombs weighing three pounds each were used in this target area from prior to 1940 through approximately 1942. The site of the former Bomb Target Kearny Field has been developed numerous times to support runway operations at MCAS Miramar and is currently in the middle of the operational runways. Much of it is currently covered by paved or concrete surfaces associated with the airfield.

The former Bomb Target Kearny Field MRS was first subject to a limited-scope MRP investigation in 2007 when a preliminary assessment was conducted. Fieldwork conducted during a 2010 site inspection found no evidence from an instrument-assisted visual survey of munitions and explosives of concern or munitions debris. Analyses of near surface soil samples collected at the site also found no impact to soils from munitions constituents. Results from analyses were within acceptable ranges for human health and ecological screening levels. No further action was recommended in the 2011 final site inspection report, and the Department of Toxic Substances Control agreed with the recommendation to close MRS 12 in a July 2011 letter.

MRS 13 is a 9.19-acre parcel in the secured flight operations area in the central portion of western MCAS Miramar, which is located north of the main runway and south of the helicopter staging area. The former Bore Site Range was used to calibrate wing-mounted guns on aircraft. An outdoor range configured as a typical bore site range was operated in the southern portion of the site adjacent to the taxiway at the installation’s airfield. In the 1950s, after the range was relocated to accommodate construction of Taxiway P. The outdoor range was replaced in 1969 by a tunneled bore sight range, which was used until 2000. Munitions used in at the bore site range included 0.30 caliber, 0.50 caliber cartridge, and 20-millimeter ammunition. Currently, the area is covered by a flight line fueling station tarmac, former firing pads, and undeveloped land covered with sparse vegetation.

The former Bore Sight Range MRS was first subject to a limited-scope MRP investigation in 2006 when a preliminary assessment was conducted for a 3.2-acre site identified from historical records as the former range. During a 2010 site inspection, munitions debris was observed and documented, including projectiles from used target practice rounds. No munitions and explosives of concern were identified at the former range. Elevated levels for metals associated with munitions were detected in soil samples collected at the 3.2-acre site, although all were below human health risk screening levels. A recommendation was made to extend the southern and northern site boundaries to include areas where a 20-mm projectile and where visibly disturbed soil from range demolition activities were observed. Based on the findings of the site inspection, a remedial investigation and feasibility study for munitions constituents was recommended for the newly expanded 9.19-acre MRS 13.

Remedial investigation fieldwork was conducted at the 9.19-acre MRS 13 in 2013. No munitions and explosives of concern were identified, and previously observed munitions debris was removed and properly disposed of. Results from soil samples found one or more metals above installation background levels, but human health and ecological risk screening found no unacceptable risk to human and ecological receptors. No further action was recommended for MRS 13 in the 2014 remedial investigation report, and the site was closed with Department of Toxic Substances Control approval.

MRS 14 is located within the East Miramar Range Complex. Because it is located within an operational range, MRS 14 was removed from the MRP before the preliminary assessment phase.

MRS 15 is comprised of 28 acres in the northwestern portion of the installation. The former Rifle Range – 200 Targets was used between 1917 and 1920 for small arms training, specifically 0.30-caliber rifle ammunition. It consisted of a target berm and three firing lines. The site is currently located beneath the installation golf course and its parking areas, associated buildings on the east side of Anderson Avenue, as well as beneath the recreational field on the northeast corner of Anderson Avenue and Bauer Road.

The former Rifle Range – 200 Targets was the subject of a preliminary assessment and site inspection completed in 2011, at which time it was added to the installation’s MRP. No evidence of munitions and explosives of concern, munitions debris, or historical range features such as berms were observed. Metals associated with munitions were detected in soil samples at concentrations exceeding installation background levels and human health or ecological screening criteria. A recommendation was made that a remedial investigation and feasibility study be conducted for MRS 15.

Fieldwork for the remedial investigation at MRS 15 was conducted in 2020. Following finalization and review of the results of the remedial investigation, the Navy will evaluate remedial alternatives. The site is currently open.

Back to Top

UST Site 1, also known as the Navy Exchange Main Gas Station, is located near the intersection of Miramar Court and Maxam Avenue, near the western entrance of MCAS Miramar. The facility is the primary service station on the air station for non-military vehicles. Leaking gasoline and underground storage tanks at UST Site 1 contaminated soil and groundwater in the immediate area. Sampling conducted in 1997 indicated groundwater beneath the site was impacted with petroleum hydrocarbons. Contaminated soil was excavated and disposed of offsite. In 1997, the Navy Exchange Main Gas Station site was added to the Miramar ERP.

Free product was observed in groundwater monitoring wells during a May 2000 visit, initiating a series of groundwater monitoring events, some of which included free product removal. Results from groundwater sampling conducted in 2007 indicated that additional investigation was required to assess the extent of groundwater contamination. Additional wells were installed and monitored in 2011 and 2012 to provide further data to aid in characterizing contamination at the site. The results of this assessment indicated that there were still small quantities of free phase petroleum present, and that the contaminant plume was migrating under the building.

A site remediation pilot study using a passive soil gas venting system was initiated in 2016 and was shown to be effective at intercepting and reducing the contamination migrating under the building. Because of the success of the pilot study, the site entered long-term monitoring, which included groundwater monitoring, free product removal, and passive soil venting system monitoring. In 2020, the Regional Water Quality Control Board concurred with site closure under the Low Threat Underground Storage Tank Case Closure Policy. The site currently remains open, pending proper destruction of existing monitoring wells at the site.

Back to Top