| Action Date |
Action |
Description |
DEC Staff |
| 8/24/2012 |
Update or Other Action |
Draft UFP-QAPP for PA/SIs at Sites SA034, SA033, AT035, & AT032 Site Characterization/Cleanup at Sites TA008, TU948, TU110, TU111, TU112, TU949, & SS001 August 2012 received.
Site SA034 – Powerline Drum Site consists of approximately 120 drums. The site is located within Joint Base Elmendorf-Richardson (JBER)-Richardson (JBER-R) (the former Fort Richardson Army Post) in Anchorage, Alaska. The site has not been previously investigated. The Preliminary Assessment/Site Inspection (PA/SI) activities proposed in this Uniform Federal Policy Quality Assurance Project Plan (UFP-QAPP) for Site SA034 are being conducted to determine whether a release has occurred &, if so, whether soil or groundwater has been impacted.
Site SA034 –Powerline Drum Site was first discovered in 2002. This remote site contains approximately 120 drums located under a power line near TA-416 Road. The drums have various military markings from the 1940s- to 1960s era military drum styles; however, their contents are unknown. Photographs of the drums taken during October 2004 & August 2012 site walks are shown on Figure A-1.2. As shown in the photographs, the drums are primarily found in clusters of 2 to 3 drums, with several larger areas containing up to approximately 30 drums.
No previous investigations have been completed at the site, so little is known about the site-specific geology & hydrogeology.
The Phase I sampling & analytical approach includes the following:
- Collect samples of drum contents (as needed) from drums containing enough liquid to sample.
- Samples will be analyzed for toxicity characteristic leaching procedure (TCLP) volatile organic compounds (VOCs), TCLP semivolatile organic compounds (SVOCs), TCLP polychlorinated biphenyls (PCBs), gasoline-range organics (GRO), diesel-range organics (DRO), residual-range organics (RRO), TCLP pesticides, TCLP herbicides, & TCLP metals.
The Phase II sampling & analytical approach includes the following:
Surface soil sampling & analysis:
- Following drum removal & sampling, approximately 20 surface discrete soil samples will be collected. The actual number of samples will be based on the sample collection frequency per the surface area of the drum pile, as defined in Table 2B of the ADEC Draft Field Sampling Guidance (2010). Since the approximate area of the drum pile is 100 by 50 ft (5,000 sq ft), Table 2B indicates that the following samples should be collected: 10 screening samples for the first 250 square feet plus one per additional 100 square feet (approximately 58 screening samples total); & two laboratory samples for the first 250 sq ft, plus one for each additional 250 square feet (approximately 20 samples total). Sample locations will be based on observations of the ground surface beneath the drums. These observations include photoionization detector (PID) readings, soil staining, sheens, unusual discolorations, & odors.
- All samples will be analyzed for VOCs, SVOCs, PCBs, GRO, DRO, RRO, pesticides, herbicides, & metals.
See site file for additional information.
|
Louis Howard |
| 8/29/2012 |
Site Added to Database |
A new site has been added to the database |
Mitzi Read |
| 9/21/2012 |
Document, Report, or Work plan Review - other |
Staff provided review comments on the UFP-QAPP for Priority Sites on JBER-Richardson.
WS #17 Sampling Design & Rationale
WS #17 & all appendices
General Comment
The sampling design should specify that soil samples will be collected at the highest PID reading & where visual/olfactory evidence indicates contamination. The text seems to indicate that only the two clean intervals below contamination will be sampled regardless of field screening or visual observations. The contractor shall not limit sampling to two planned intervals below the last evidence of contamination, even though the boring logs may document contamination in other intervals within the borings. This will result in an increased number of samples per boring.
The text states: “Soil Excavation. If soil contamination is found to pose unacceptable risk using the HRC model under Method 3, & excavation is the selected remedial approach, the following decision rules will be used to guide the excavation:
– Soil contamination in the upper 15 feet bgs that creates unacceptable direct contact risk (the 95 UCL ~10,250 milligrams per kilogram [mg/kg]) will be excavated.
– Soil contamination creating unacceptable vapor intrusion or migration-to-GW risk down to 25 feet bgs will be excavated, if soil contamination below 25 feet bgs does not create unacceptable risk.”
Delete reference to 95 UCL.
a. Soil – A 95% UCL may be proposed for department review & approval in accordance with 18 AAC 75.380(c). If it is not approved, the maximum concentration will be used for site determination. It does not appear that sufficient data will be collected to calculate a valid 95% UCL.
b. Water – 95% UCL is not acceptable for GW. The maximum GW site concentrations shall be used.
Last bullet
Vapor Intrusion
ADEC requests JBER elaborate on the term “significant” with regards to HRC & vapor intrusion. ADEC’s October 2010 Conceptual Site Model guidance (see Appendix D) contains a list of volatile compounds & discusses (see 3.3.2) when a building is close enough to contamination to prompt additional evaluation (30 feet from a petroleum source & 100 feet from a non-petroleum source).
See site file for additional information.
|
Louis Howard |
| 1/2/2013 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 79325 name: SA034 Powerline Drum Site |
Louis Howard |
| 4/1/2013 |
Update or Other Action |
Draft PA/SI report received for review & comment.
DRO were detected in all surface soil samples, with three samples exceeding the ADEC Method Two migration-to-GW SL of 250 mg/kg. Several VOCs were detected in surface soil; however, only PCE, methylene chloride, & 2-hexanone were detected above the SLs. The semivolatile organic compound (SVOC) analyte bis(2-chloroethyl)ether was detected in surface soil above the ADEC Method Two MGW SL of 0.0022 mg/kg, at one location, at a concentration of 0.0621 mg/kg.
Several pesticides & herbicides were detected in surface soil; however, 4-(2,4-dichlorophenoxy) butyric acid (2,4-DB) & 2-methyl-4-chlorophenoxyacetic acid (MCPA) were the only herbicides detected at concentrations greater than the EPA risk-based protection of GW SLs. The EPA risk-based protection of GW SLs do not include a DAF. The HRC uses a default DAF of 13.2 (ADEC, 2011), & if this DAF is applied to the EPA SL for 2,4-DB, there would be no exceedance for the one sample. All exceedances for 2,4-DB & MCPA were between the method detection limit & the limit of quantitation, & the associated detected results were qualified as estimated & flagged “J.”
The herbicides do not appear to be associated with the drums at this site because they are widespread at low-level concentrations across the site, were not detected in residual drum liquids, & could possibly be due to overspray from vegetation control within the adjacent powerline easement.
Recommendations
-Using hand shovels, investigate the EMI anomalies to verify buried drums are not present.
-Conduct further investigation at the locations presented in Table ES-1 to evaluate the vertical & or horizontal extent of contamination for the contaminants of potential concern (COPCs) presented in Table ES-1.
-Determine the need for an interim removal action within the areas identified in Table ES-1 to remove the specific COPCs to below soil cleanup levels.
-Restore the site to natural conditions after investigation activities are complete:
–Fill in the locations where surface soil samples were collected, remove all lath & pin flags marking sample locations, grid, & drum locations.
–Spread piled vegetation & trees placed at the perimeter of the site across the cleared area & allow nature to re-establish itself.
See site file for additional information.
|
Louis Howard |
| 4/19/2013 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the draft UFP-QAPP for SA034.
General Comments
The text and document discusses use of the Method Three dilution attenuation factor (DAF) of 13.2 to screen out exceedances of EPA Risk-based SSLs (DAF of 1 for protection of groundwater) for various contaminants of potential concern. This approach was not mentioned in the draft UFP-QAPP nor was it agreed to by EPA and ADEC when the project managers reviewed and approved the UFP-QAPP for PA/SIs at Sites SA034, SA033, AT035, and AT032 Site Characterization/Cleanup at Sites TA008, TU948, TU110, TU111, TU112, TU949, and SS001 Joint Base Elmendorf-Richardson, Alaska.
Surface Soil Results
The text states: “The herbicides do not appear to be associated with the drums at this site because they are widespread at low-level concentrations across the site, were not detected in residual drum liquids, and could possibly be due to overspray from vegetation control within the adjacent powerline easement.”
ADEC requests JBER provide a figure with the power line easements clearly identified overlain with the herbicide sample locations [4-(2,4-dichlorophenoxy)butyric acid (2,4-DB) and 2-methyl-4-chlorophenoxyacetic acid (MCPA].
In accordance with 18 AAC 75.335(g), ADEC has calculated migration to groundwater cleanup levels for 2,4 DB and MCPA. The calculated migration to groundwater cleanup level for 2,4 DB is 0.36 mg/kg and for MCPA it is 0.0174 mg/kg.
In accordance with 18 AAC 75.325 (g) If using method two or method three for determining the applicable soil cleanup levels as described in 18 AAC 75.340 - 18 AAC 75.341, or if applying the groundwater cleanup levels at Table C in 18 AAC 75.345, a responsible person shall ensure that, after completing site cleanup, the risk from hazardous substances does not exceed a cumulative carcinogenic risk standard of 1 in 100,000 across all exposure pathways and does not exceed a cumulative noncarcinogenic risk standard at a hazard index of one across all exposure pathways. Guidance on cumulative risk determinations is provided in the department's Cumulative Risk Guidance, dated June 9, 2008. The department’s Cumulative Risk Guidance, dated June 9, 2008, is adopted by reference.”
Chemicals with HQs less than 1 generally need only be retained for uncertainty assessment. If the HI is less than 1, yet the chemical has potential to bioaccumulate, it should be retained for further evaluation in the risk assessment.
5.3
Soil Analytical Data
The text states: “The herbicides do not appear to be associated with the drums at this site because they were not detected in residual drum liquids, are widespread across the site, and could possibly be due to vegetation control within the adjacent powerline easement (Figure 1-1). Normal herbicide use is not considered a release under CERCLA (Federal Insecticide, Fungicide, and Rodenticide Act exemption).
JBER must meet the two conditions stated below for 2,4 DB and MCPA to be eligible for the FIFRA “release” exemption from CERCLA:
Application of the pesticide exception requires a two-part test:
(1) was the pesticide at issue registered under FIFRA and
(2) did the contamination, "result ... from the application of a pesticide product?"
Since 1947 FIFRA has required registration of all pesticides sold in interstate commerce. Prior to that time, the United States Department of Agriculture had regulatory jurisdiction over pesticides. In 1972 the registration requirement was extended to all pesticides sold in both interstate and intrastate commerce, essentially all commercial pesticides.
An "application" is, "... the placement of a pesticide at or on the site where the pest control or other responses is desired." An "Application" also appears to include any use of the pesticide in accordance with manufacturers' instructions.
EPA does not, however, consider the spill of a pesticide to be either an "application" of the pesticide or in accordance with the pesticide's purpose. Please provide additional supporting information that the herbicides were registered and applied at SS034 and not discharged, released or spilled at SS034.
While CERCLA may exempt 2,4 DB and MCPA in this instance from if it is shown to be registered and applied at or on the site, ADEC will still require the contaminants be investigated for nature and extent for the purposes of cumulative risk calculations as required by 18 AAC 75 at SS034.
|
Louis Howard |
| 1/27/2014 |
Update or Other Action |
ADEC received a work plan for review and comment.
This Work Plan describes a phased approach to determine the nature and extent of contamination
at the site and support a risk evaluation. This site-specific Work Plan follows the Uniform
Federal Policy-Quality Assurance Project Plan (UFP-QAPP) format, and the work will be performed under the Joint Base Elmendorf-Richardson, Basewide Uniform Federal Policy-Quality Assurance Project Plan (JBER Basewide UFP-QAPP) (USAF, 2013a).
The purpose of this Work Plan is to further characterize the nature and extent of petroleum
hydrocarbon–contamination at SA034, evaluate potential risks to human health and the
environment within the proper regulatory framework, and determine whether further action is
necessary to advance the site toward site closure. Depending on the contaminants of potential
concern (COPCs) ultimately identified at the site, the risk evaluation will be performed within
the framework of the Comprehensive Environmental Response, Compensation, and Liability Act
of 1980 (CERCLA) or the ADEC site cleanup process (Title 18 Alaska Administrative Code
Chapter 75 [18 AAC 75] Sections 325 to 390, and 18 AAC 78 Section 600) (ADEC, 2012a;
ADEC, 2012b). |
Louis Howard |
| 1/28/2014 |
Document, Report, or Work plan Review - other |
Staff provided comments on the draft "focused site inspection" work plan.
General Comments
The title of this document states it is a “Focused Site Inspection”. ADEC will treat this site inspection & the previous PA/SI work as a “Preliminary Source Evaluation” (PSE) I & II under the Fort Richardson Federal Facility Agreement or as a “Site Assessment” under the State-Fort Richardson Environmental Restoration Agreement if SA034 does not become a new source area under CERCLA after the PSE process is conducted.
There are three management options for sources reviewed in a PSE processes: a) No Further Action (NFA), in terms of planning for FFA remediations (such a decision would not prohibit future activity undertaken pursuant to State authority); b) inclusion in an RI/FS; or, c) recommendation for IRA.
Executive Summary
If SA034 does not qualify as a new source area under the Fort Richardson Federal Facility Agreement, then SA034 shall be subject to the risk evaluation requirements for Method Two or Method Three [see 18 AAC 75.325(g)] & any cleanup subject to 18 AAC 75.340(k) requirements for calculating cumulative risk.
To be perfectly clear, the risk “evaluation” is not the same as Method Four risk assessment or a risk assessment conducted as part of a CERCLA RI/FS as required by the Fort Richardson Federal Facility Agreement. The document does not detail how a “risk evaluation” would specifically be conducted under CERCLA or 18 AAC 75. A risk evaluation does not relieve JBER of the need to address maximum allowable concentrations for petroleum hydrocarbons within the 0-15’ interval as required by 18 AAC 75.340(j)(3).
Project Planning Session Summary
Please clarify why the aromatic & aliphatic equivalent distribution of DRO is being characterized in the context of risk since there has not been any discussion of a Method Three cleanup or Method Four risk assessment where these values are to be used. Comment applies throughout the document where aromatic & aliphatic equivalent distribution is discussed. The Method Three approach with the HRC will not be applicable nor approved for this site since the HRC will not approved for SA034 due to herbicides being commingled with DRO & VOCs (PCE).
Conceptual Site Model
Page 18
Nature & Extent of Contamination
Please provide the date (month & year) of when the EPA RSLs were accessed.
Page 19
Table 10-1
No explanation is given in the footnotes to the table for “U” “UJ” & “B” flagged data or in the text where “J” flagged data is described in detail. Data qualifying conventions shall follow Table 36-5 of the Final Basewide UFP-QAPP. Please provide an explanation of these specific data flags (“U” & “B”) for the reader in accordance with Table 36-3 of the Final Basewide UFP-QAPP.
See site file for additional information.
|
Louis Howard |
| 4/24/2014 |
Document, Report, or Work plan Review - other |
Staff provided comments on the RTCs and redline document "Draft Powerline Drum PSE II Work Plan".
Comment revision accepted for comment #13. Pending any EPA comments/concerns being addressed and incorporated, the document may be finalized.
Please be aware that the exceedance of the MAC of 22,200 mg/kg DRO at 0-1 foot below ground surface (Sample ID SA034-SS09) will need to be addressed regardless of the risk evaluation by the HRC per the HRC User Manual (Jan. 2011):
Page 38
Page 12, Site Status Summary
“Site closure considerations not addressed in the calculator, such as free product recovery and the cleanup of stained soils* to the extent practicable, maximum allowable concentration criteria**, compliance with non-risk based groundwater criteria, should be addressed in the site characterization report.”
*18 AAC 75.325 Site cleanup rules: purpose, applicability, and general provisions (E) evaluate and perform a cleanup of surface soil staining attributable to a hazardous substance; AND
*18 AAC 75.380 Final reporting requirements and site closure (b)(9)(G): a demonstration that surface soil staining was evaluated and that a cleanup of that staining was performed;
**18 AAC 75.340(j)(3): the maximum allowable concentrations for petroleum hydrocarbons described in Table B2 of 18 AAC 75.341(d) must be attained in the surface soil and the subsurface soil.
Surface soil is defined as 0-2' bgs [18 AAC 75.990(127)]
|
Louis Howard |
| 12/18/2014 |
Document, Report, or Work plan Review - other |
EPA retraction of no further action under CERCLA.
EMAIL from EPA: I’m going to retract my statement that we are NFA under CERCLA on this site. I hadn’t digested the new contaminant list fully, and now that we have detections in 2014 for 2,4,5-T (Agent Orange), we really should be looking for dioxin, and especially 2,3,7,8-TCDD which was the primary carcinogenic contaminant in Agent Orange.
http://www.publichealth.va.gov/exposures/agentorange/basics.asp
EPA has RSL’s for 2,3,7,8-TCDD and a MCL in groundwater. Sampling for dioxins could be limited to the areas with 2,4,5-T and 2,4-D in soils. I searched to see if TCDD is a known contaminant in 2,4-DB, another one of the phenoxy herbicides, but didn’t get any definitive hits. 2,4-DB was attributed to background at SA034.
Given the very low MCL, it would be good to also analyze groundwater samples for the dioxins.
It appears the analysis is complicated and will require an amended QAPP.
EPA method 1613 is preferred (or CLP method DLM02.2)
http://www.epa.gov/superfund/programs/clp/dlm2.htm
http://water.epa.gov/scitech/methods/cwa/organics/dioxins/index.cfm
http://water.epa.gov/scitech/methods/cwa/organics/dioxins/upload/2007_07_10_methods_method_dioxins_1613.pdf
The AF will need to calculate TEFs for all compounds based on toxic equivalency to 2,3,7,8-TCDD then sum them up for the TEQ. Attached is the template the EPA chemists use for the TEF calculations. Make sure you specify in the QAPP what TEFs/TEQs will be used and what ND= (0.0/0.5/1/0).
Sandra Halstead |
Louis Howard |
| 3/11/2015 |
Update or Other Action |
Staff received the draft Preliminary Source Evaluation 2 Report for review & comment.
The following conclusions were made:
• Previously identified metallic anomalies could not be located to a depth of 2’ bgs; however, a metal detector did indicate the presence of metal at or near the ground surface in the location of the EM anomalies.
• Herbicides 2,4-D, 2,4-DB, 2,4,5-T, MCPA, & MCPP; insecticides Aldrin, gamma-BHC, Heptachlor, & Heptachlor epoxide; the nine VOCs PCE, 1,2-dichloroethane (chloromethane), 1,2-dichloropropane, benzene, ethylbenzene, MTBE, methylene chloride, naphthalene, & 2-hexanone; the two SVOCs 1-methylnaphthalene & bis(2-chloroethyl)ether; & DRO in soil were found above initial project screening levels.
• The compound 2,3,7,8-TCDD is a documented by-product from the manufacturing process of the herbicide 2,4,5-T that is present in the soil. Sampling for dioxins in soil was not conducted as part of this investigation effort & remains a data gap.
• The lateral & vertical extent of herbicide, insecticide, VOC, SVOC, & DRO contamination in soil above initial project screening levels has been defined, with the exception of benzene in SA034-SB01 reported at a depth of 25’ bgs (but well below the ADEC Method Two, Table B1 cleanup level).
• There is no unacceptable risk site wide to human health under current use for herbicide, insecticide, VOC, & SVOC compounds present in soil. However, when future sampling for dioxins in soil is completed, the human health risk under current use may need to be reevaluated.
• Under potential future use, there is no unacceptable human health risk site wide through the direct contact, outdoor inhalation, & indoor inhalation pathways for herbicide, insecticide, VOC, & SVOC compounds present in soil. However, when future sampling for dioxins in soil is completed, the human health risk under potential future use may need to be reevaluated.
• GW ingestion remains a complete exposure pathway under potential future land use; however, GW has not been encountered onsite to a depth of 50’ bgs (GW is estimated at a depth of 110’ bgs), & soil contamination does not extend beyond 25’ bgs. Therefore, the migration to GW pathway is presumed incomplete, & the risk associated with the GW ingestion pathway is subsequently assumed negligible.
• Using the HRC, the cumulative cancer risks for the current industrial exposure scenario for the petroleum contaminated area meets the regulatory risk standard of 1E-05.
• The cumulative cancer risks for a current hypothetical residential exposure scenario, using the HRC for the petroleum contaminated area, is above the regulatory risk standard of 1E-05. Risk is primarily being associated with nondetect levels of benzo(a)pyrene (BAP). Actual risk associated with these compounds is assumed considerably less.
• Using the HRC for the petroleum contaminated area, the cumulative noncancer HI estimates for the current industrial & hypothetical residential exposure scenarios meet the regulatory risk standard of 1.
• Potential risks posed by the GRO, DRO, & RRO aromatic & aliphatic fractions for the petroleum contaminated area are below the regulatory risk standard of 1 for all pathways for the industrial exposure scenarios.
• Under the hypothetical residential exposure scenarios, the potential risks posed by the GRO, DRO, & RRO aromatic & aliphatic fractions are above the regulatory risk standard of 1 for direct contact with DRO aromatic & DRO aliphatic fractions. All remaining exposure pathways are below the regulatory risk standard of 1.
• Modeled impacts to GW by GRO, DRO, & RRO are well below regulatory standards.
• A single DRO hit in surface soil (22,200 mg/kg at SS09) remains above the direct contact/ingestion cleanup level of 10,250 mg/kg. [and the maximum allowable concentration of 12,500 mg/kg]
• The completed SLERA determined that site-related constituents would not pose a potential for unacceptable risks to wildlife using habitats at SA034. Under current site conditions no further evaluation or remedial action is warranted for ecological risk at SA034. However, when future sampling for dioxins in soil is completed, the ecological risk may need to be reevaluated.
Recommendations
• Because levels of the herbicide 2,4,5-T are present in the shallow surface soil at SA034, additional surface soil sampling should be conducted to determine the presence/absence of dioxins at SA034.
• To further address the remaining petroleum contamination, additional sampling or remedial action would be necessary to ensure the DRO in soil is at or below the direct contact/ingestion cleanup level of 10,250 mg/kg, & risk associated with BAP & dibenz(a,h)anthracene is shown to be within regulatory standards. |
Louis Howard |
| 3/12/2015 |
Meeting or Teleconference Held |
Meeting held on SA034 March 12, 2015.
Path Forward: Soil sampling to determine the presence/ absence of dioxins in soil, define lateral extent of DRO at SS09 (22,000 mg/kg) and sample PAH concentrations of benzo(a)pyrene and dibenzene(a,h)anthracene by Method 8270 SIM (lower detection limits).
Soil Sampling for Dioxins
?
Surface soil samples collected by hand auger, 0 to 2 feet bgs following SOP-16
?
3 locations where herbicide 2,4,5-T was detected in surface soil during the 2014 investigation
?
SA034-SS05 (2,4,5-T at 0.0812 mg/kg)
?
SA034-SS19 (2,4-5-T at 0.0707 mg/kg)
?
SA034-SS20 (2,4,5-T at 0.0483 mg/kg)
?
2 locations where the herbicide 2,4,5-T is not known to be present (background)
?
SA034-SS28 (within powerline corridor)
?
SA034-SS33 (within SA034, but not near drum locations)
?
1 new location 200 feet north of SA034-S33 theoretically free of drum leaks/spills and powerline herbicidal application
QA/QC samples collected based on site-specific samples collected, not program-wide as presented in WS#20 of the UFP-QAPP
?
Submit soil samples for laboratory analysis by EPA Method 8290 (Test America)
?
Method SOPs included in 2014 BasewideUFP-QAPP update
?
2,3,7,8-TCDD TEQ MDL = 1.5E-10
?
2,3,7,8-TCDD TEQ LOQ = 1.0E-09
?
Project soil screening levels (2,3,7,8-TCDD)
?
EPA November 2013 RSL = 2.6E-07 (risk-based protection GW)
?
ADEC Cleanup Level = 5.8E-05
?
EPA’s Advanced KM TEQ Calculator will be used to address non-detected and rejected results when calculating the TEQ concentrations.
Soil Sampling for DRO and PAHs
?
5 surface soil sample locations for DRO and PAHs are proposed
?
Resample source area (SS09)
?
4 lateral extent samples radially 5 feet from source area sample
?
Hand auger from 0 to 2 feet bgs following SOP-16
?
Deeper subsurface soil samples are not planned as the vertical extent was determined by the PSE2 investigation
?
Submit soil samples for laboratory analysis of DRO by Alaska Method AK102 and PAHs by EPA Method 8270 SIM
?
QA/QC samples collected based on site-specific samples collected, not program-wide as presented in WS#20 of the UFP-QAPP
PSE2 Report Addendum
?
Re-evaluate site risks
?
CERCLA COCs
?
Human health and ecological screening level risk evaluation similar to PSE2 Report
?
Petroleum COCs
Surface soil sampling –June/July 2015
?
Additional soil sampling, if necessary –August 2015
?
HRC |
Louis Howard |
| 3/18/2015 |
Document, Report, or Work plan Review - other |
Staff provided comments on the draft preliminary source evaluation II report. Main comment was centered on reevaluation of risk to human health and the environment when dioxin soil sampling is complete. Staff agreed the report may be finalized pending any comments from EPA being incorporated into the document. |
Louis Howard |
| 3/24/2015 |
Update or Other Action |
Distance to Subsurface Water Right Location 45837 is approximately 3,093 feet, Customer Name: Customer Name: R & E Lab and USDOD US ARME COE COLD REGIONS, File: ADL 45837,
Legal Description: LOT 5, SAID LOT LOCATED WITHIN NW1/4 SW1/4 SECTION 24,
TOWNSHIP 14 NORTH, RANGE 3 WEST, SEWARD MERIDIAN.
THE LOCATION OF THE WATER SOURCE TO WHICH THE WATER RIGHT GRANTED
APPERTAINS IS A DRILLED WELL, DEPTH UNKNOWN, WITHIN LOT 5, SAID LOT
LOCATED WITHIN NW1/4 SW1/4 SECTION 24, TOWNSHIP 14 NORTH, RANGE 3 WEST
SEWARD MERIDIAN
3,000 gpd
OTTER LAKE RECREATION AREA
TAKE/USE PT: SAME AS ABOVE.
RECREATION SERVICES. |
Louis Howard |
| 4/16/2015 |
Document, Report, or Work plan Review - other |
EPA provided comments on the PSE2 Report. Main comments were regarding requesting clarification on statements describing why herbicide background samples were taken and "normal" use of herbicides for vegetation control under powerlines. Finally, incremental sampling method for dioxin sampling was requested to address the data gap on dioxins. |
Louis Howard |
| 4/24/2015 |
Update or Other Action |
Preliminary Source Evaluation (PSE) 2 draft work plan addendum received for review and comment.
The purpose of this Work Plan Addendum is to further refine the extent of DRO and polynuclear aromatic hydrocarbon (PAH)-contaminated soil, assess the presence of dioxin in surface soil, evaluate potential risks to human health and the environment, and determine whether further action is necessary to advance the site toward site closure. Depending on the contaminants of potential concern (COPCs) ultimately identified at the site, the risk evaluation will be performed by comparing non-petroleum COPCs against project screening levels and using the Hydrocarbon Risk Calculator to evaluate petroleum COPCs. |
Louis Howard |
| 5/11/2015 |
Document, Report, or Work plan Review - other |
Staff provided comments on the draft work plan addendum. Main comments were regarding the reference to the exceedances of diesel range organics as being above the maximum allowable concentration and that if reconfirmed by sampling, it will need to be removed from the 0-15' bgs interval regardless of the risk evaluation results from the Method 3 hydrocarbon risk calculator. |
Louis Howard |
| 5/21/2015 |
Document, Report, or Work plan Review - other |
The Alaska Department of Environmental Conservation (ADEC) has received the Final Preliminary Source Evaluation 2 Report for SA034 JBER, Alaska dated May 2015 for SA034 (CS DB Hazard ID 25904). ADEC has no further comments on the final version of the document and approves the document.
|
Louis Howard |
| 10/26/2015 |
Document, Report, or Work plan Review - other |
Staff provided comments on the remedial investigation/feasibility study (RI/FS) Work Plan (WP).
Main comments were regarding the WP being a management plan (a primary document under the FFA) and that the purpose of the plan is defined by the 1994 Fort Richardson FFA. Additional comments were to requests soil gas sampling to the list of activities to be performed at SA034 since TCE contamination is present and should buildings be constructed in the future, risk from VI should be determined as part of the investigation. Finally, staff requested 1-4 dioxane analysis be performed.
See site file for additional information. |
Louis Howard |
| 4/22/2016 |
Update or Other Action |
Draft PSE2 Addendum received for review and comment.
The following conclusions were made regarding SA034:
• The lateral extent of COPCs in soil at SA034 is approximately 10 by 20 feet and is limited to
surface soil since soil samples from deeper borings SA034-SB01 and SA034-SB02 to 50 feet bgs did not contain COPCs above screening levels.
• The historical high DRO concentration in surface soil (22,200 mg/kg at SA034-SS09) is believed to no longer be present, based on resampling the location in 2015 (335 J mg/kg at SA034-SS37).
• The updated HRC risk evaluation indicates that for the petroleum soil source area, the rounded
cumulative cancer risks for the current industrial and hypothetical residential exposure
scenarios meet the regulatory risk standard of 1 × 10-5.
• Using the HRC, the cumulative noncancer HI estimates for the current industrial and
hypothetical residential exposure scenarios meet the regulatory risk standard of 1.
• The surface soil dioxin/furan KM TEQ values for mammals/humans (8.6 × 10-8 to 2.6 × 10-7 mg/kg) are less than the site-specific groundwater protection soil screening level (5.8 × 10-7 mg/kg).
• The industrial and residential cancer risk estimates from dioxins/furans in soil for all four
samples are less than the low end of EPA’s risk-management range of 1 × 10-4 to 1 × 10-6, and
the noncancer HQs are less than 1.
• None of the KM TEQ values for mammals or birds are above the ecological screening levels or HQ of 1.
• As presented in the PSE 2 Report, all other risk criteria meet the standards for human health
and ecological risk (USAF, 2015a)
Based on the risk evaluations presented above, SA034 does not pose an unacceptable risk to human
health or the environment, and no further action (NFA) is recommended for SA034. SA034 meets
the requirements of the USAF definition for site closeout and should be considered a closed site.
See site file for additional information. |
Louis Howard |
| 5/23/2016 |
Cleanup Complete Determination Issued |
Cleanup complete determination issued by ADEC.
The cleanup level for soils at SA034 containing DRO contamination is 4,540 mg/kg in the Under 40-inch Zone based on the ingestion pathway within the 0 to 15’ interval below ground surface (bgs). Modeling using the Hydrocarbon Risk Calculator, in accordance with Method Three under 18 AAC 75.340, successfully demonstrated that residual petroleum contaminants in soil at SA034 do not pose a migration to groundwater risk/concern.
The HRC was used to evaluate risk from petroleum contamination at SA034. The HRC is designed for sites with petroleum contamination—specifically the petroleum fractions, BTEX, PAHs, and other compounds dissolved in petroleum—with the intention and purpose of assessing human health risk from this type of contamination.
The estimated rounded cumulative cancer risk at SA034 for the current industrial and hypothetical residential exposure scenarios, across all exposure pathways, (1 x 10-7 and 4 x 10-7 respectively), is below the regulatory risk standard of 1 x 10-5 for petroleum hydrocarbons.
The estimated cumulative noncancer HI at SA034 for the current industrial and hypothetical residential exposure scenarios, across all exposure pathways, (0.00049 and 0.0016 respectively) is below the regulatory risk standard of 1. SA034 meets the ADEC risk criteria [18 AAC 75.325(g)] for petroleum hydrocarbons. The risk posed by the DRO aromatic and aliphatic surrogate fractions meets the risk standard for each exposure pathway, assuming a residential land use scenario.
An ecoscoping form was completed for SA034 and no observed surface soil staining, no impacted vegetation, no surface water or sediment runoff from the site. The ecoscoping form indicates that a more in-depth risk evaluation is not needed and that the SA034 site conditions are protective of the environment.
Based on a review of the environmental records, ADEC has determined that SA034 has been adequately characterized and has achieved the applicable requirements under the site cleanup rules. ADEC is issuing this written determination that cleanup is complete, subject to a future department determination that the cleanup is not protective of human health, safety, welfare, or of the environment [18 AAC 75.380(d)]. A “cleanup complete” designation will be entered for SA034 in the Contaminated Sites Database.
See site file for additional information. |
Louis Howard |
