| Action Date |
Action |
Description |
DEC Staff |
| 2/24/2010 |
Update or Other Action |
During the initial foundation study prepared in February 2010 by the United States Army Corps
of Engineers (USACE), seven borings (AP-4723 through AP-4729) were advanced to collect geotechnical and chemical samples at the ELM300 F-22 Weapons Release Shop site. Volatile organic compound (VOC) samples were collected and analyzed for solvents due to the site history and known contamination nearby. In all, sixteen soil samples including two duplicates were collected from the borings for chemical analysis.
The field crew during this sampling event consisted of Shannon & Wilson Consultants
geotechnical engineer Oscar Lane, Discovery Drilling driller Scott Clinkenbeard and driller
helpers Adam Saunders and Jeremy Cromwell, and USACE chemist Amanda Heath
(CEPOA-EN-ES-M).
Based on the results of this sampling, the soil samples revealed the presence of the following contaminants:
1. Arsenic was detected at levels above ADEC cleanup levels in most samples (6.9 mg/kg highest level detected at 0 - 2' bgs). These levels are around the ingestion contact limit of 5.5 mg/kg specified in 18 AAC 75.341, Table B-1 and are slightly below the background range determined for Fort Richardson soils.
2. DRO was detected in one sample at a concentration greater than the ADEC cleanup levels (3,800 mg/kg highest level detected at 4.5' - 6.5' bgs).
3. Methylene chloride was detected in eleven samples at concentrations greater than the ADEC migration to groundwater cleanup level, but well below the inhalation and dermal contact levels established in Table B-1 of 18 AAC 75.341. The presence of this compound is ascribed to laboratory contamination.
4. Tetrachloroethene (PCE) was detected in three samples at concentrations (0.082 mg/kg highest concentration detected at 9.5 - 11.5' bgs) greater than the ADEC migration to groundwater cleanup level, but well below the inhalation and dermal contact levels established in Table B-1 of 18 AAC 75.341.
5. Trichloroethene (TCE) was detected in six samples at concentrations (0.54 mg/kg highest concentration detected at 4.5 - 6.5' bgs) greater than the ADEC migration to groundwater cleanup level, but well below the inhalation and dermal contact levels established in Table B-1 of 18 AAC 75.341.
6. Benzo(a)pyrene was detected in one sample (1.8 mg/kg at 0-2' bgs) at a concentration greater than the ADEC ingestion level established in Table B-1 of 18 AAC 75.341.
Fuels: GRO, DRO (1,120 mg/kg at 0-4' bgs and 3,800 mg/kg at 4.5 - 6.5' bgs) and RRO were found at low concentrations in most of the samples. DRO was detected in one sample (10ELM300-04SL, AP-4726, 4.5-6.5’) well above ADEC cleanup levels.
4.2.2 Volatile Organic Compounds (VOCs): Low concentrations of a few VOCs were detected in several samples.
Methylene chloride (10ELM300-14SL, AP-4724, 9.5-11.5’ and 10ELM300-04SL, AP-4726, 4.5-6.5’) and tetrachloroethene (PCE) (10ELM300-14SL, AP-4724, 9.5-11.5’; 10ELM300-03SL, AP-4726, 2.5-4.5’ and 10ELM300-04SL, AP-4726, 4.5-6.5’) were detected above ADEC cleanup levels in a few samples.
Trichloroethene (TCE) was detected above ADEC cleanup levels in several samples (10ELM300-08SL, AP-4723, 4.5-6.5’; 10ELM300-14SL, AP-4724, 9.5-11.5’; 10ELM300-12SL, AP-4725, 0-2’; 10ELM300-12SL, AP-4725, 4.5-6.5’; 10ELM300-03SL, AP-4726, 2.5-4.5’ and 10ELM300-04SL, AP-4726, 4.5-6.5’).
Polynuclear Aromatic Hydrocarbons (PAHs): Most of the PAH compounds were detected at low concentrations in all samples. Benzo(a)pyrene was detected above the ADEC cleanup level in two samples (10ELM300-01SL, AP-4729, 0-2’ and 10ELM30017SL, AP-4729, 2.5-4.5’).
Pesticides: One pesticide compound was detected in a couple samples at concentrations well below ADEC cleanup levels.
PCBs: One PCB compound was detected in one of the 8 samples, well below ADEC cleanup levels. AP number AP-4729 sample ID 10ELM300-01SL TB-7 0-2'bgs 2/22/2010 PCB-1260 0.89 mg/kg (0.05) ML. ML qualifier = Analyte result is considered an estimated value biased (high,low) due to matrix effects.
The matrix spike and/or matrix spike duplicate recoveries for anthracene, benzo(g,h,i)perylene, benzo(k)fluoranthene, chrysene, indeno(1,2,3-cd)pyrene, phenanthrene, arsenic, selenium and PCB-1260 in the MS/MSD associated with sample 10ELM300-01SL were below QSM acceptance limits. Results for these analytes in the primary sample are flagged “ML”. Data usability is not impacted since all results are well below ADEC cleanup criteria. |
Louis Howard |
| 4/28/2010 |
Update or Other Action |
Memorandum for ADEC. SUBJECT: Response to ADEC Comment on Draft 2009 Zone 1 Field Activities Report (Ref: ADEC Memo, 12.Mar 10)
1. This memorandum is in response to ADEC's concern as to why diesel-range organics (DRO) and gasoline-range organics (GRO) at select groundwater plumes were not sampled in 2009 as
previously agreed in a January 14, 2003 meeting. Specifically, ADEC's comment (Attachment 1) is in reference to Section 3.7.1 Implications of Contaminant and Geochemical Monitoring, Page 3-17 of the draft 2009 Zone 1 Field Activities Report, which stated:
"The text states: When these parameters were monitored from 1999 to 2007, GRO concentrations in this monitoring well exceeded cleanup levels while DRO concentrations hovered near the cleanup level. ADEC requests the Air Force provide an explanation or a memorandum to the site file as an appendix to the document on why DRO and GRO were eliminated from the monitoring program as previously agreed to in a January 14, 2003 meeting with ADEC, USAF and EPA."
2. The analytes in question were not included in the Zone 1 groundwater monitoring program
for FY09 due to an administrative oversight.
The agreement to monitor for DRO and GRO was captured in meeting minutes (Attachment 2), not in a more formal mechanism such as a decision document or memorandum to the site file. In preparation for programming of project requirements, we reviewed the governing documents for the Zone 1 sites. None of the governing documents for Zone 1 sites identified GRO/DRO as a contaminant of concern (COC); therefore, GRO/DRO sampling was not programmed or conducted in 2009.
3. The U.S Air Force agrees with ADEC's request to continue sampling for diesel-range organics (DRO) and gasoline-range organics (GRO) for CERCLA sites with fuel-related plumes. Minutes of a 14 Jan 03 meeting with EPA, ADEC and DRS, provided with the above referenced ADEC memo, documents that the Air Force agreed to add DRO/GRO into the sampling program under the following conditions:
a. The decision will be documented in the 5-Year Review. The addition of DRO/GRO to the program should be introduced in the 5-Year Review under· mention of new issues affecting protectiveness.
b. The Air Force will NOT add DRO/GRO as a CERCLA ARAR, but will compare DRO/GRO results to ADEC cleanup levels in the annual reports and will discuss in subsequent 5-Year Reviews. The benefit of this is that if CERCLA COCs meet ARARs, the Air Force can achieve a partial delisting.
c. The Air Force will add DRO and GRO to the suite of analyses at monitoring wells associated with fuel plumes starting in 2004.
d. The Air Force will not pursue a decision document with ADEC on DRO/GRO until more data is gathered on the extent of the problem.
e. Until a decision document is signed with ADEC, GRO and DRO concentrations will be compared to ADEC regulations in 18 AAC 75 (Table C, Groundwater Cleanup Levels; 1,500 ug/L for DRO, 1,300 ug/L GRO).
f. Sampling frequency for DRO/GRO will follow the latest Decision Guide for Sampling Frequency (see 2002 Basewide Annual Report). "Immediately up gradient" means within a 2-year warning line, similar to that generated for OU5.
g. ADEC GRO/DRO criteria apply to groundwater, not to seeps which daylight as surface water. Criteria in 18 AAC 70 (TAR, TAqH) apply to surface water.
4. The fact that these analytes were not included in the Zone 1 groundwater monitoring program
for FY09 is attributed to an oversight. The USAF will add DRO/GRO into the suite of analyses
at monitoring wells associated with fuel-related plumes for Zone 1 (LF04 South and WP14) and
will prepare a memo to the site file to prevent this type of oversight from occurring in the future.
The USAF strategy will be to compare DRO/GRO and total aromatic hydrocarbon (TAH)/total
aqueous hydrocarbon (TAqH) sample results as contaminants of interest with current ADEC
regulations in 18 AAC 75 - Table C - Groundwater Cleanup Levels and 18 AAC 70 for surface
water. Should you have any questions, please feel free to contact me at (907) 552-2875.
Signed Gary Fink YF-02 Chief, Environmental Restoration. |
Louis Howard |
| 6/17/2010 |
Update or Other Action |
EPA provided a copy of the chemical data report to ADEC which was from February 2010 sampling activities at ELM300 project near the Solvent Shed just north of Bldg. 16716 (Hangar 15). 7 borings (AP-4723 through AP-4729) were advanced to collect geotechnical & chemical samples. In all, 16 soil samples including 2 duplicates were collected from the borings for chemical analysis. The existing building (Bldg 17720) has been in use since the early fifties & has been used for the maintenance of equipment for its entire history. There is currently a small bldg in the footprint of the new construction that is slated for demolition.
This building is marked as the “Solvent Storage Building” on a 1957 as built drawing of the original bldg. According to the current user of the building, solvents are no longer stored in this area. The presences of this solvent storage bldg along with the historical uses of the site suggest that solvent contamination may be possible at the project site.
As a result, additional VOC samples were taken. An adjacent bldg (Hangar 15, Bldg 16716), has known soil contamination associated with it. This bldg is located to the southwest of the project site. Hangar 15 has been used for aircraft maintenance, & chemicals & solvents were thought to have been disposed of in floor drains that led to dry wells. This site is currently part of OU4 & has a status of no further action required. In addition, a 20,000 gallon underground heating oil tank (HOT)was removed directly to the east of Hangar 15.
This tank was found to have leaked & 225 tons of POL contaminated soil was removed from the site. Additional fuel contaminated soils were left in place under the bldg. GW monitoring is currently ongoing in the area under OU5, which comprises all of EAFB GW monitoring activities. Contamination from both Building 16716 & from maintenance activities at the weapons release shop have the possibility to impact the construction site.
The soil samples collected from the borings (generally, from the surface, 2.5-4.5 ft bgs, 4.5-6.5 ft bgs, & at 5-foot intervals thereafter) were field-screened with a PID. 16 soil samples (including two duplicates) were submitted to the lab for chemical analysis. Seasonal frost was encountered in all borings to a depth of approximately 2.5 feet bgs.
No visual evidence of chemical contamination was observed, & all but one PID readings were below the 20 ppm that requires the segregation of soil. (NOTE TO FILE 20 PPM is an arbitrary number for field screening and not acceptable as “definitive data” for clean soils). For AP-4726, the PID reading for five feet was 98 ppm. The project manager, Jill Chouinard, was notified & the soil was segregated for proper disposal. A VOC, DRO & RRO sample (10ELM300-04SL) was taken at that depth. One soil sample exceeded the field-screening criterion for containerization. Those soil cuttings were segregated into a 55-gallon drum. A VOC, DRO & RRO sample (10ELM300-04SL) was taken.
All other soil samples did not exceed the field-screening criterion. These soil cuttings were backfilled into the borings from which they were extracted, as described in the SAP. Excess soil was spread on the ground nearby. Decontamination or potable water was used to hydrate the bentonite chips used to seal the borings or discarded on the ground near the borings.
Highest Detected chemicals:
Arsenic 6.9 mg/kg (migr. gw 3.9 mg/kg),
benzo(a)pyrene 1.8 mg/kg (migr. to gw 0.49 mg/kg),
DRO 3,800 mg/kg (migr. to gw 250 mg/kg),
methylene chloride 0.029 mg/kg (migr. to gw 0.21 mg/kg),
tetrachloroethene-PCE 0.4 mg/kg (migr. to gw 0.024 mg/kg), &
trichloroethene-TCE 0.54 mg/kg (migr. to gw 0.020 mg/kg). |
Louis Howard |
| 6/18/2010 |
Document, Report, or Work plan Review - other |
Email correspondence to EPA, Donna Baumler (USAF) and Gary Fink (USAF) review of SAP and data report:
ADEC's quick comments on the MILCON Site "sampling plan" and chemical data report which was NOT sent to ADEC via the Air Force. Unless someone has an opinion otherwise, this appears to be [Upgradient] close to a [Downgradient] OLD source OU4 SD29 Bldg. 16716 under the Federal Facility Agreement.
1) APPL Lab report not provided
2) Arsenic cleanup level for under 40 inch zone is 4.5 mg/kg (not 5.5 mg/kg)
3) No supporting documentation for the assumption of methylene chloride as lab contaminant. In fact, section 5.1.3 states that the lab method blank was ND except for 1,2,4 Trichlorobenzene. Additionally, numerous samples are reported as ND, although the laboratory reporting limit,
0.26 mg/kg, does not meet the ADEC cleanup level, 0.016 mg/kg.
4) PAHs not analyzed in sample -04SL, the highest diesel range organics (DRO) result.
5) Ft. Rich Background metals referenced instead of Elmendorf (Basewide Background Sampling Report January 1993).
6) Section 5.1.6 Surrogates. The listed compounds, methylene chloride, PCE, TCE are VOCs, not PAHs.
7) Samples -04SL for DRO and -17SL for RRO are not flagged "QL" as stated in section 5.1.6.
8) What is the definition of "well below ADEC cleanup levels" where the identified low biases do not affect data usability?
9) DRO for sample -17SL is reported as ND (530 mg/kg) well above the 250 mg/kg cleanup level. Additionally, the RRO result is ~8x the primary -01SL result. Due to data variability, it is uncertain if this location is below cleanup levels.
10) Sample -01SL PCB 1260 reported as 0.89 mg/kg ML. This is not "well below" the PCB cleanup level of 1 mg/kg.
11) Section 5.3. Data tables should list laboratory MDLs to confirm analytes which detection limits did not meet cleanup levels.
12) The benzo(a)pyrene cleanup level referenced in Table B1 at 0.49 mg/kg is for direct contact and not for ingestion. ADEC does not list ingestion cleanup levels only direct contact, outdoor inhalation or migration to groundwater cleanup levels.
So what do we do now that we have demonstrated soil contamination with TCE and PCE, benzo(a) pyrene above Table B1 migration to groundwater levels at [a downgradient source] SD29 Hangar 15? Never mind about the MILCON project which unearthed this information for us.
The ROD only stated that only Trichloroethene and tetrachloroethene are only in the groundwater and not the soil. |
Louis Howard |
| 6/18/2010 |
Update or Other Action |
Email response from Donna Baumler (USAF) to ADEC.
I was asked to send the sampling plan to the EPA to see if they needed to approve the COE's sampling plan prior to them beginning their soil borings. This is not an AF environmental project at this time; all of the reports, plans and field activities are being managed by the COE.
I will forward these comments to the COE and Gary will be taking the lead on coordinating with the COE when he returns next week. I understand the soil boring work will not begin until 6 Jul 10. |
Louis Howard |
| 6/22/2010 |
Document, Report, or Work plan Review - other |
EPA (Jacques Gusmano) sent comments to Donna Baumler and Gary Fink (USAF): EPA agrees with the comments made by ADEC on the proposed Work Plan for ELM300.
In addition, Section 3.1 Purpose of Sampling, lists ADEC Guidance as the regulatory authority. The correct primary regulatory authority is RCRA, 40 CFR 262.11. The COE will be the Generator of potential hazardous waste( since lab results show "F" listed waste) when they excavate this soil. Under 40 CFR 262.11 they must determine if this solid waste is hazardous waste.
In Section 3.2 Scope of Sampling, the work plan states that samples will be collected from the same borings used in the past. EPA asks how this will give you any new information about quantity of waste, to say nothing of nature and extent?
Also a map displaying the location of borings is needed.
Since the contamination defined by the preliminary effort demonstrates halogens along the border of the proposed excavation, EPA requires some entity on Elmendorf , either COE or CES/CEANR, determine the full nature and extent. |
Louis Howard |
| 6/24/2010 |
Update or Other Action |
Donna Baumler (USAF) sent EPA and ADEC Project managers email message:
Thanks for your quick review of the COE's sampling and analysis plan for soil boring work to be conducted at the addition to Building 17720, as well as their final chemical data report from previous geotechnical work conducted in Feb 2010.
Jacques, your comments on the sampling and analysis plan (SAP) have been incorporated and the revised SAP is attached, along with a new figure that shows the Feb soil borings along with the locations of this summer's proposed soil borings.
Louis, the COE revised the SAP prior to my receiving your comments this morning. Hopefully, it addresses most of your concerns that are related to the COE project.
Louis, a word document addressing your comments on the chemical data report (Apr 2010), which was already final, is attached. Unfortunately, the COE's chemical data report is for work conducted in Feb 2010 and we were not given an opportunity to review it; however, the COE has agreed to incorporate your comments into the chemical data report for these soil
borings and that report is expected mid-Aug 2010.
Remember this is a COE project and the purpose of their sampling is to quantify the amount of potentially contaminated soil that may require disposal under the terms of the construction contract for the addition to Building 17720. CEANR recognizes that additional investigation will be required to more fully delineate the contamination and is working with AFCEE
to secure restoration funding. Again, thanks for your quick responses and please let me know if you have any questions or concerns. |
Louis Howard |
| 6/28/2010 |
Document, Report, or Work plan Review - other |
Email Message to Gary Fink & Donna Baumler (USAF) & J. Gusmano (EPA)
GENERAL Comments: The revised CORPS Sampling & Analysis Plan for ELM300 is an improvement. However, ADEC has additional comments & concerns which will not be addressed by the focused sampling effort conducted by the CORPS: "...to determine whether significant soil contamination exists in the area to be excavated in the course of the planned construction activities, which might necessitate off-site transport & remediation of the excavated soil."
There is not a record in ADEC's Prevention & Emergency Response spills database of the CORPs or the AF providing a spill report for the release associated with ELM300. Please provide a copy of the spill notification provided to ADEC if one exists which shows the CORPS or AF reported the release to ADEC as soon as they had knowledge of the discharge (18 AAC 75.300).
It is not apparent from the Chemical Data Report whether the CORPS followed the AF Basewide spill notification process: "Contaminated soil may be encountered during excavation activities. If contaminated soil is encountered, the contractor should immediately contact 552-SPIL." Which should have been immediately followed by a spill report to ADEC.
Need to see if the concentrations of TCE/PCE found in the soil [during this additional soil sampling & subsequent AF site characterization) are indicative of vapor intrusion risks (if applicable). The GW pathway has not been eliminated from consideration at ELM300 which is of concern to ADEC.
*Target GW levels (Draft Vapor Intrusion Guidance for Contaminated Sites, July 2009: Appendix G DEC GW Target Level) - PCE 5.7 ug/L (Residential GW level) 29 ug/L (Commercial GW level) TCE 0.55 ug/L (Residential GW level) 2.8 ug/L (Commercial GW level)
* Do not rely on target levels when GW contamination is less than 5 feet from the building foundation or a vapor source is less than 15 feet from the building foundation & preferential pathways, significant openings, or low building air exchange exist.
Constructing a building over the site may create a migration to indoor air pathway that could be a risk driver should additional soil contamination be found which is higher than what was detected in the February 2010 geotechnical work.
General concerns that need to be addressed include: 1) determining whether constructing a new building & any related infrastructure built by the CORPS, as part of MILCON ELM300 on EAFB, will obstruct required site characterization & cleanup work; 2) creating exposure pathways (VI migration to indoor air); 3) waste characterization & management.
SPECIFIC Revised Plan Comments & Concerns
2.2 Site History & Known Contamination An adjacent building (hangar 15, building 16716) has known soil contamination associated with it. This building is located to the southwest of the project site. Hangar 15 has been used for aircraft maintenance, & chemicals & solvents were thought to have been disposed of in floor drains that led to dry wells. This site is currently undergoing GW monitoring & is part of OU4. In addition, a 20,000 underground heating oil tank (HOT) was removed directly to the east of hangar 15. This tank was found to have leaked & 225 tons of POL contaminated soil was removed from the site. Additional fuel contaminated soils were left in place under the building. GW monitoring is currently ongoing at OU4.
ADEC Comment: The plan does not address DRO contamination (3,800 mg/kg) found during February 2010 geotechnical work at ELM300. Existing DRO contamination from Building 16716 Hangar 15 in soil & GW would NOT flow towards or impact the ELM300 site which is the northeast (NE) of Building 16716 Hangar 15.
OU4 RI/FS: GW in the shallow aquifer flows to the south & west across OU 4 & is influenced by the presence of the Elmendorf Moraine, which acts as a GW barrier to the north, & by Ship Creek, which is the point of discharge for the majority of the shallow aquifer flow to the S. (Page ES-2) At OU 4 East [includes Hangar 15 Building 16716], GW appears to flow primarily to the W, with an increasing SW flow component at OU 4 West. The deflection of GW flow occurs due to the presence of the Elmendorf Moraine, which trends to the NE just W of OU 4 (Section 2.3.1.1 Page 2-22)
See site file for additional information. |
Louis Howard |
| 6/29/2010 |
Update or Other Action |
EPA email message to Donna Baumler and Gary Fink (USAF)
Since construction is scheduled for the near future, I suggest a meeting sometime in the next few days.
We have to be sure the construction footprint is properly investigated for two reasons; to avoid RCRA classification and disposal violations of excavated soil and to prevent the possibility of vapor intrusion to workers/residents.
ADEC has a conference available for the next week. I am available tomorrow and Thursday of this week, and all but Tues. pm next week. |
Louis Howard |
| 6/29/2010 |
Update or Other Action |
Spill notification sent by USAF Wade Gilpin to Mark Sielaff. RE: Unknown source-soil contamination. During excavation at Construction Site ELM300, nea~ Bldg 17720, soil borings were
taken and analyzed. Analysis indicated the presence of some contaminated soil (elevated
TCE, PCE, ORO). No visual indication of any spill. We determined that the contamination
was from a historic contaminated site. Sampling & Analysis plan has been submitted to L.
Howard.
17720 Talley Avenue Lat: 61 degrees 15' 16" N Long: 149 degrees 46' 37.29" W. Unknown soil contamination identified druing construction site (ELM300) boring sample analysis. Analysis indicated the following: TCE 0.54 mg/kg, PCE 0.4 mg/kg, DRO 3,800 mg/kg. No visual indication of spill observed.
|
Louis Howard |
| 7/7/2010 |
Update or Other Action |
Donna Baumler (USAF) emailed EPA and ADEC PMs the MEMORANDUM FOR CEPOA-PM-M (Jill Chouinard)
SUBJECT: Sampling & Analysis Plan, Foundation Study HTRW Soil Sampling & Analysis, ELM300 F-22 Weapons Release Shop, EAFB, Alaska.
The proposed ELM300 site is directly to the west of the existing weapons release shop (building 17720) on the west side of Talley Avenue, on EAFB, AK. The site is bounded on the west by building 17726 and Taxiway “G”, on the south by Hangar 15, and on the north by a temporary storage building.
The primary purpose of sampling is to determine whether significant soil contamination exists in the area to be excavated in the course of the planned construction activities, which might necessitate off-site transport & remediation of the excavated soil. This project is not intended to be a comprehensive environmental investigation. The primary regulatory authority to be addressed by this sampling is Resource Conservation & Recovery Act (RCRA), 40 CFR 262.11. Soil cleanup levels will be based upon 18 ACC 75.
Soil samples collected by the chemist for chemical analysis will be collected from the same borings positioned & drilled by the environmental engineer. The current scope of drilling includes a total of 7 borings to a depth of 16’. Typically, samples will be collected from the following approximate intervals:
• 0 -4 ft bgs,
• 4 - 8 ft bgs,
• 8 – 12 ft bgs,
• 12-16 ft bgs,
The interval with the greatest response from the field screening kit will also be selected for lab chemical analysis. A lab sample will also be taken at terminal depth to confirm no further contamination.
The lab methods have been chosen to analyze for the known contamination on site. Analyses will be performed at two depths on every boring. Selection of one sample for lab analysis will be at the discretion of the sampler, based on field-screening results & other observations. The second sample for lab analysis will be at the terminal depth.
These numbers were arrived at by assuming the generalized distribution detailed below, then adjusting the quantities to include QC duplicate samples & trip blanks:
• DRO: Two samples submitted from every borings.
• RRO: Two samples submitted from every borings.
• GRO: Two samples submitted from every borings.
• VOCs: Two samples submitted from every boring.
This distribution was created primarily for estimating purposes, & the field sampler has discretion in the final distribution of sampling points.
All soil samples will be field screened with a photoionization detector (PID) with a 10.6 eV lamp, which has been calibrated with an isobutylene gas mixture referenced to benzene. The PID is useful as a general field survey tool & will be used to screen soil samples for absence or presence of POL contaminants. A heated headspace reading above 20 ppm will be used as an indication of potential soil contamination. If there is potential soil contamination, a lab sample will be taken to confirm.
All soil samples will be field screened using AQR Color-Tec® colorimetric tubes. These tubes react to the presence of chlorinated volatile organic halocarbons.
Soil cuttings determined to be contaminated through field screening will be containerized in open-top steel drums. The drums will be labeled in a manner that will clearly indicate the project name, sampler, point of contact phone# & date from which the soil was obtained. This information will be written on a COE IDW adhesive label applied to the drum. Soil samples collected during drilling will be used to characterize the containerized soil.
Analytical results from the soil borings will be used to determine the chemical nature
of the drummed cuttings & wash water, if any. If analytical results show that the drum contents are hazardous, the EAFB Environmental office will be contacted & the material disposed through the EAFB Hazardous Control Center. The location is at Building 4314 & the point of contact is 552-3435. If the contents are petroleum contaminated only, arrangements will be made for thermal treatment.
Soil cuttings that have been field screened as non-contaminated will be backfilled in the borehole or spread out on the surface within the vicinity of the borehole. If the borehole is though pavement, the cuttings will be transferred & spread out in a non-paved area. The cuttings will be spread out in a discrete area, to avoid leaving a conspicuous soil pile. Any portions of the borehole determined to be contaminated will be backfilled with bentonite & hydrated in situ with potable water to prevent a conduit to the GW aquifer. The top several feet of each borehole will also be backfilled with bentonite for this same purpose |
Louis Howard |
| 7/9/2010 |
Document, Report, or Work plan Review - other |
ADEC sends email message to Donna Baumler (USAF), Jacques Gusmano (EPA).
4.4 Field screening Page 4
Text states: "A heated headspace reading above 20 ppm will be used as an indication of potential soil contamination. If there is potential soil contamination, a laboratory sample will be taken to confirm."
COMMENT: ADEC disagrees. All soil separated as "clean" i.e. headspace reading 20 ppm and below will still require laboratory confirmation that the soil is actually clean and not above ADEC cleanup levels for petroleum, oil and lubricants. The PID is not to be used to determine whether soil is clean or not, but it will be used to determine where to take samples and segregate soils potentially clean and potentially dirty (both to be sampled). The PID ppm level chosen by the Corps is not to be used as a substitute for required laboratory analyses.
4.10 Investigation-Derived Waste Page 7
Text states: "Soil cuttings determined to be contaminated through field screening will be containerized in open-top steel drums.
Soil cuttings that have been field screened as non-contaminated will be backfilled in the borehole or spread out on the surface within the vicinity of the borehole."
COMMENT: ADEC disagrees. All soil cuttings will be determined to be contaminated through laboratory analysis and not on the basis of field screening results <20 ppm or > 20 ppm threshold. Soil cuttings will be determined to be non-contaminated after laboratory results show cleanup levels have not been exceeded. Only then will the cuttings be allowed to be backfilled in the borehole or spread out on the surface within the vicinity of the borehole.
In ADEC’s experience PID screening results do not necessarily correlate with laboratory results for weathered diesel fuel. For example, the following PID readings obtained from soil samples and diesel range organics (DRO) laboratory analysis demonstrates that there is a wide variance in field screening readings versus actual laboratory results obtained from another Air Force installation in Alaska (there was no biogenic interference to confound the DRO results either):
PID Reading DRO laboratory analysis
1 ppm 911 mg/kg
4 ppm 1,600 mg/kg
5 ppm 1,130 mg/kg
6 ppm 11,600 mg/kg
10 ppm 35,800 mg/kg
10 ppm 3,520 mg/kg
12 ppm 1,600 mg/kg
12 ppm 28,200 mg/kg
17 ppm 18,100 mg/kg
17 ppm 67,200 mg/kg
19 ppm 17,300 mg/kg
20 ppm 1,350 mg/kg
Bottom line, field screening results will NOT be the sole determining factor in any investigation for demonstrating soil meets ADEC cleanup levels. |
Louis Howard |
| 7/13/2010 |
Document, Report, or Work plan Review - other |
EPA email message to Donna Baumler (USAF) and ADEC.
EPA agrees with ADEC. The PID is first a safety tool and then a screening tool. It reduces the number of samples taken and can direct analysis to possible hot spots. However, "clean closure" and" waste characterization" must be corroborated by analytical methods.
|
Louis Howard |
| 7/13/2010 |
Document, Report, or Work plan Review - other |
EPA sends email message to Donna Baumler & Gary Fink (USAF) and ADEC.
EPA and ADEC agree that if the edits mentioned in the ADEC comments are made , the ELM 300 SAP is approved. |
Louis Howard |
| 7/15/2010 |
Update or Other Action |
USAF (Gary Fink) sends COE response to comments via email to ADEC, EPA and COE.
The language used in the SAP Section 4.4 is a generic statement. We will be using field screening to focus our investigation. The increments that receive the highest reading will be submitted as a sample to the laboratory to be analyzed for AK 101/102/103 and 8260B. The PID levels will not be used as a substitute for laboratory analysis.
We will be collecting our soil cuttings into a drum. After all boring soil cuttings are collected; we will submit a composite sample of the cuttings for laboratory analysis by the methods specified in the above comment. When we receive laboratory results of this sample, we can then determine what is to be done with the soil cuttings.
|
Louis Howard |
| 7/15/2010 |
Document, Report, or Work plan Review - other |
ADEC responds via email to Gary Fink & Donna Baumler (USAF) and EPA Jacques Gusmano.
This addresses ADEC's comments and concerns and work plan is approved with these changes clarifying screening methodology and IDW procedures. |
Louis Howard |
| 7/20/2010 |
Update or Other Action |
A second sampling event (19-20 July 2010) consisted of eight additional borings (TB-1 through TB-8). The field crew over the course of this second event consisted of USACE environmental
engineers Neil Folcik and Craig Scola (CEPOA-ESP), and USACE chemist Amanda Heath
(CEPOA-EN-ES-M). |
Louis Howard |
| 8/12/2010 |
Update or Other Action |
Foundation Study HTRW Survey F-22 Weapons Release Shop ELM300 (10-012) received. The second sampling event, a total of eight borings (TB-1 through TB-8) were advanced using a Geoprobe at the ELM300 site, beginning 19 July and continuing through 20 July 2010. See Figure 2 for specific boring locations.
During the second sampling event in July 2010, no visual evidence of chemical contamination was observed, and all PID readings were below the 20 ppm that requires the segregation of soil. However, due to the knowledge that the site is contaminated, all soil samples were segregated.
During the July 2010 sampling event, all soil samples did not exceed the field-screening
criterion but were not returned to the boring. All soil cuttings were segregated into a 55-
gallon drum left on site. Decontamination or potable water was used to hydrate the bentonite
chips used to seal the borings or discarded on the ground near the borings. Solid waste (i.e.,
disposable sampling equipment and other trash) was disposed of in facility trash receptacles.
DRO was detected in three samples (10ELM300-04SL, AP-4726, 4.5-6.5’, 10ELM300A2, TB-2, 0-4’ and its duplicate sample 10ELM300A9) well above ADEC cleanup levels.
Low concentrations of a few VOCs were detected in several samples. Methylene chloride 10ELM300B6, TB-6, 12-16’) and tetrachloroethene (PCE) 10ELM300B6, TB-6, 12-16’; 10ELM300A7, TB-7, 4-8’ and 10ELM300B7, TB-7, 12-16’) were detected above ADEC cleanup levels in a several samples.
Trichloroethene (TCE) was detected above ADEC cleanup levels in many samples 10ELM300B2, TB-2, 12-14’; 10ELM300A3, TB-3, 4-8’; 10ELM300B3, TB-3, 12-16’; 10ELM300A4, TB-4, 8-12’; 10ELM300B4, TB-4, 12-16’; 10ELM300B9 (duplicate of 10ELM300B4);10ELM300A6, TB-6, 4-8’; 10ELM300B6, TB-6, 12-16’; 10ELM300A7, TB-7, 4-8’; 10ELM300B7, TB-7, 12-16’ and composite sample 10ELM300A10).
Recommendations
1. All contaminated soils shall be removed within the building footprint and project areas as defined in the project drawings and in strict accordance with the project specification sections.
2. To protect existing building foundations during the excavation, an excavation design by a licensed structural engineer shall be accomplished in accordance with project criteria and specifications.
3. The limit of the TCE/PCE plume was not determined. Therefore, additional sampling should be accomplished to determine the extents of the contamination plume.
4. A passive vapor mitigation system (similar to a radon mitigation system) shall be installed in the new facility as defined in the project specification section.
5. The contractor must be prepared to accomplish control measures to mitigate the site workers potential exposure to the reported contaminates and relevant exposure pathways (e.g. from fugitive dust, etc.). As a minimum, the contractor shall be in full compliance with all safety requirements specified in EM 385-1-1, “Safety and Health Requirements Manual”.
|
Louis Howard |
| 8/17/2010 |
Update or Other Action |
Email from Donna Baumler (USAF) to EPA and ADEC PMs.
Attached is the Corps of Engineers (COE's) draft chemical data report, which presents the analytical results for soil samples taken in two chemical investigations in the area of a proposed project (ELM300) for an addition to the F-22 Weapons Release Shop. The most recent sample event, conducted in Jul 2010, reveals TCE at concentrations higher than ADEC's
migration to groundwater cleanup level in 17 samples collected from 8 new soil borings in the area of this proposed project.
The COE would like to meet this week, if possible, to discuss the recommendations of this report (ie, contaminated soil removal and vapor mitigation system). To determine the volume of TCE-contaminated soil required to be removed, the COE needs to know if they are only required to excavate the soil to the depth that is going to be disturbed during the
excavation for the building construction, since in some cases they didn't hit "clean" soil at the bottom of the boring and in other cases contamination was at a depth of 6-8 ft?
Jill - Do you have any figures with the new/previous soil boring locations that had TCE concentrations above cleanup levels and at what depths? I didn't see any figures in this report comparing the proposed work site with the location of soil borings with elevated TCE concentrations.
Sorry for the delay in getting this report out to all, but I was out of the office at the end of last week. I am available for a meeting most of this and next week. Let me know when you are available to meet and I will try to coordinate with all... |
Louis Howard |
| 8/18/2010 |
Document, Report, or Work plan Review - other |
ADEC email sent to Donna Baumler & Gary Fink (USAF), EPA Jacques Gusmano and COE staff.
Unless I am missing something, the field notes did not show how or where the composite sample 10ELM300A10 was obtained. There was no mention of composite sampling being proposed in the final approved work plan for the site either. Also, composite soil sampling is not approved for VOCs analyses to show compliance with cleanup levels.
ADEC 2010 Draft Field Sampling Guidance:
III. Soil Sampling
A. General Guidelines
" Unless approved by the ADEC project manager on a site specific basis, all laboratory soil samples MUST be discrete samples and may NOT be composited before analysis, EXCEPT when required by federal regulations, e.g. Toxic Substances Control Act (TSCA) for Polychlorinated Biphenyls (PCBs) or Resource Conservation and Recovery Act (RCRA) waste disposal characterization."
UST Procedure Manual:
4.6 Collecting Soil Samples
"... (1) unless otherwise approved by ADEC, all laboratory soil samples MUST be grab samples and may NOT be composited before analysis, EXCEPT that soil samples for total arsenic, cadmium, chromium, and lead that are for screening purposes may be composited in the field or in the laboratory before analysis"
8.3.3 Determining the Final Validity of Samples "Samples that are NOT collected in accordance with this chapter will be considered INVALID; in particular, a sample will be considered INVALID if
(6) the sample was composited before analysis, unless compositing of the sample is explicitly specified by this chapter or approved by ADEC in the workplan required under 18 AAC 78;" |
Louis Howard |
| 8/20/2010 |
Document, Report, or Work plan Review - other |
ADEC email message sent to Donna Baumler & Gary Fink (USAF) and EPA Jacques Gusmano and the COE.
DEC's comment (so far) on the report would be that utilization of the 95% UCL is not appropriate for determining background concentrations (i.e. Page 6 of the report). Other statistical methods and/or evaluations are required.
Comparison of the arsenic levels to for Fort Richardson background soils is not appropriate for ELM300 source area on Elmendorf Air Force Base. Please remove reference to Fort Richardson background soils from the report.
See ADEC Webpage: Statistical Design / Analysis section at http://www.dec.state.ak.us/spar/guidance.htm#csp) for "Guidance for Comparing Background and Chemical Concentrations in Soil for CERCLA sites, EPA 540-R-01-003 OSWER 9285.7-41 September 2002".
|
Louis Howard |
| 8/23/2010 |
Meeting or Teleconference Held |
23 AUGUST 2010, 1300 Location: 673rd CEAN Conference Room ELM300 Weapons Release Shop
Attendees:
Jill Chouinard (USACE PM), Thomas Oh (USCACE IH), Scott Kendall (USACE Env Engr), Amanda Heath (USACE Chemist), Jacques Gusmano (US EPA PM), Louis Howard (ADEC PM), Earl Crapps (ADEC Chemist), Gary Fink (USAF 673 CES/CEANR)(Env), Donna Baumler (USAF 673 CES/CEANR), Venetia Ruehle (USAF PM).
Background
• Intent: Create a new addition to the weapons release shop and replace existing temporary facility with a permanent structure.
• Solvent storage shed located next to building
• TCE and PCE contamination found.
• Reviewed maps showing estimate of the contaminant plume location
• Verified that during the last sampling effort the composite was used for a RCRA disposal characterization.
Assumptions
• Extent of contamination may continue underneath existing building(s), to the south, east, and west (currently undefined).
• Contamination found was identified as NOT being part of an existing site. It is unknown if it will eventually connect to an existing site, but it is up gradient of the identified groundwater contamination from SD29. 673 CES/Environmental is completing the requirements for the contaminated site notification under CERCLA.
• DEC will accept the use of EPA’s vapor intrusion model based on Johnson-Ettinger screening risk model. The variables used in the JE model will be default criteria of 30 years residential exposure and 25 years for commercial/industrial workers (not the criteria defined in the DoD Vapor Intrusion Handbook, Jan 2009). For example, the DOD Vapor Intrusion Handbook provides military specific exposure factors conducted by the USAF (2000), enlisted residence time 2.51 years and 1.90 years for officers with a 95th percentile residence time on station 7.86 years enlisted and 4.58 years for officers. It was noted that civilian staff on base work much longer than active duty personnel, so, it was agreed that the default 25 year exposure period should be used.
Facts
• TCE/PCE contamination exists
• Arsenic, benzo (a) Pyrene, DRO, and methlyene chloride were found on site above ADEC cleanup levels.
• ADEC verified that the arsenic levels were within expected background levels for Elmendorf AFB. Reference to Ft Richardson background levels in our documentation should be changed.
RECOMMENDATION
Revised to COA3 during the meeting. Excavate to depth of construction within project limits. Verify that a sub slab depressurization system is in place for the new structure for remainder of contamination, and add an appropriate vapor mitigation system to the existing building.
The team identified that the following samples are needed prior to construction:
• Three borings in the area of previous samples TB3, TB6 and TB7 are needed to establish the vertical extent of contamination for solvents. Samples will be collected for VOCs.
o One of these borings should include a groundwater sample
o Each of these borings should be to the depth of groundwater (estimated at 30 – 40 ft)
o Soil gas samples should be taken in each of these borings
o Soil samples should be taken every 5 feet in each boring to depth of groundwater
• Sub-slab sampling is recommended under building number 17720
• 673 CES will coordinate with Bioenvironmental Engineering to find past sampling results for indoor air sampling
• Indoor air quality sampling will be completed by USACE in Building 17720
A short 1 – 2 page sampling plan will be submitted prior to the sampling effort. The additional sampling effort has been expedited and is scheduled for 10-13 Sep 10. |
Louis Howard |
| 8/31/2010 |
Update or Other Action |
USAF (Donna Baumler) sent EPA and ADEC PMs email message. In preparation for additional field work proposed for the addition to the F-22 Weapons Release Shop (ELM300 project), attached is the COE’s draft SAP and final minutes of the 23 Aug 10 meeting. Please review this 2-page sampling and analysis plan and provide your comments to me. The COE would like to begin their field work on 9 Sep 10.
SAP Objective: The U.S. Army Corps of Engineers (USACE), Alaska District, Engineering Services Branch, Materials Section (CEPOA-EN-ES-M) was tasked by the Project Management Branch (CEPOA-PM-M) to evaluate the vertical extent of trichloroethene (TCE), tetrachloroethene (PCE) and methylene chloride contamination at the ELM300 project (F-22 Weapons Release Shop) on Elmendorf AFB, Alaska. The site will be evaluated by soil, groundwater and soil gas sampling.
Sampling: Soil samples collected by the chemist for chemical analysis will be collected from the same borings positioned and auger drilled by a driller. The current scope of drilling includes a total of two borings to groundwater depth and one boring past groundwater depth for installation of a temporary monitoring well.
All soil samples collected will be field screened with a photoionization (PID) according to ADEC guidance. Soil samples were previously collected from 0 to 16 feet bgs (ref. f). For this sampling event, samples will be collected from 15 feet bgs to groundwater in five foot intervals to groundwater, approximately to 35 feet bgs. Soil samples will be analyzed by SW8260B VOCs in accordance with ADEC guidance.
The boring past groundwater depth will be converted to a monitoring well according to ADEC guidance. This well will also be sampled for SW8260B VOCs in accordance with ADEC guidance.
Soil gas samples will be secured from the three borings at a depth of 8 to 10 feet. A sub-slab sample will be secured from building 17720 as close a practicable to TB-7 (weapons vault may be in the optimal location). An ambient indoor air sample and a comparative outside sample will also be collected. All soil gas samples will be taken in Summa canisters and promptly shipped to the laboratory for analysis. Sampling will be performed in accordance with ADEC guidance and ASTM standard.
Field Quality Control: A soil and water trip blanks for each cooler containing soil and water samples for SW8260B VOCs will be included for transporting the samples for analysis. A field duplicate sample will also be collected at a rate of ten percent. Matrix spike/matrix spike duplicate samples will be collected at a rate of five percent.
Laboratory: The primary laboratory, who will be analyzing the groundwater and soil samples, will hold current State of Alaska validation status, be currently certified under ELAP for the relevant analyses, and have submitted an approved Self Declaration Form to the USACE Alaska District, mandating the use of the DOD-QSM document for analytical data quality objectives. Soil gas analysis will be performed by Columbia Analytical Services of Simi Valley, CA.
Data: After the samples are analyzed, the raw data will be subjected to a data quality review performed by a USACE chemist. The chemist will prepare an ADEC checksheet to describe the faults of the laboratory’s and sampler’s performance. A chemical data report will be prepared by the chemist, presenting the results of the sample analysis and data quality review of all the projects data. |
Louis Howard |
| 8/31/2010 |
Document, Report, or Work plan Review - other |
Email from ADEC to Donna Baumler & Gary Fink (USAF), Jacques Gusmano (EPA) and COE.
ADEC expedited review and comment on the ELM300 Project work plan/meeting minutes is to ensure that the work is done in accordance with State of Alaska environmental conservation laws and regulations. ADEC’s expedited review is provided as a courtesy to the Air Force. While ADEC may comment on other state and federal laws and regulations, our comments do not relieve responsible persons from the need to comply with other applicable laws and regulations.
Email from ADEC to Donna Baumler & Gary Fink (USAF), Jacques Gusmano (EPA) and COE.
Assumptions
• Extent of contamination may continue underneath existing building(s), to the south, east, and west (currently undefined).
ADEC Response: Not only does the Air Force have to consider soil and groundwater contamination, but also investigate the possibility of vapor intrusion (for all buildings within 100’ to the north, south, east and west) from ELM300 area.
• DEC will accept the use of EPA’s vapor intrusion model based on Johnson-Ettinger [JE] screening risk model. The variables used in the JE model will be default criteria of 30 years residential exposure and 25 years for commercial/industrial workers (not the criteria defined in the DoD Vapor Intrusion Handbook, Jan 2009).
ADEC Response: Refer to guidance from EPA and ADEC regarding vapor intrusion investigations. Environmental Protection Agency, United States (EPA). 2002. OSWER Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air Pathway from Groundwater and Soils (Subsurface Vapor Intrusion Guidance. EPA 530-D-02-004. November. Alaska Department of Environmental Conservation (ADEC). 2009. Draft Vapor Intrusion Guidance for Contaminated Sites. November
Where EPA and ADEC conflict regarding evaluation of vapor intrusion, the more conservative guidance will apply.
Other documents which may be of interest:
Interstate Technology Regulatory Council (ITRC). 2007. Vapor Intrusion Pathway: A Practical Guideline. VI-1. ITRC Vapor Intrusion Team. January.
Tri Services. 2008. Tri-Services Handbook for the Assessment of the Vapor Intrusion Pathway. Rev 4.0 Draft Final. U.S. Air Force, U.S. Navy, U.S. Army. February.
COA3
• Include vapor extraction system for both the new building and the existing structure.
ADEC Response: Include Sub Slab Depressurization System (SSDS) (passive radon mitigation system) as part of the requirements that were identified for COA3 for vapor mitigation as an option. Depending on surrounding area, there may be buildings within 100 ft. of ELM300 which require vapor mitigation measures.
Recommendation
• Verify that a sub slab depressurization system is in place for the new structure for remainder of contamination, and add an appropriate vapor mitigation system to the existing building.
ADEC Response: May have more than one building within 100’ of ELM300 which requires a vapor mitigation system.
• Soil gas samples should be taken in each of these borings
ADEC Response: a) Soil gas samples Soil gas should be collected from SEPARATE, appropriate located borings, per DEC guidance b) coordination with BioEnvironmental for possible future sampling events so that sub-slab and all indoor air samples are collected at the same time. Provide map and/or figure with soil gas sample locations, soil boring locations, for the existing building and future building footprint. See EPA and ADEC guidance regarding soil gas sampling. Important guidelines when collecting or evaluating soil gas data include the following:
1. Collect exterior soil gas samples from depths greater than 18 inches below ground surface to avoid dilution of samples with ambient air.
2. Include leak detection when installing soil gas probes at depths less than 10 feet below ground surface or subslab.
3. Install surface seals in all soil gas probes using grout or other approved materials.
4. Minimize purge volumes and sample flow rates during sampling.
5. Do not chill soil gas samples during transport.
Seasonal environmental conditions (e.g., changes in soil temperature, soil moisture, snow cover, and frozen ground) and seasonal heating and ventilation of a building can affect volatilization and migration of contaminants in soil gas. If a vapor intrusion potential exists at a site, soil gas sampling should occur in at least two seasons to identify seasonal trends.
• Sub-slab sampling is recommended under building number 17720
ADEC Response: See ADEC and EPA guidance regarding sub-slab sampling and measurement of VOCs in the sub-slab soil gas.
See site file for additional information. |
Louis Howard |
| 9/8/2010 |
Update or Other Action |
Email from COE to USAF (Donna Baumler) and ADEC. I talked with Thomas Oh and we should have our sampling plan addressing your comments shortly. What we would like to do is to split out the sampling plan for the under slab sampling and just concentrate on the outside sampling first. Our drill rig is available for a very short time and we want to take advantage of this if possible.
We will then come back later and complete the under slab sampling once that plan is approved.
I hope that since most of the comments were about the air quality sampling and under slab work that we can get a quick concurrence on our plan. Again, I do apologize for not sending your comments on to the field crew quickly. |
Louis Howard |
| 9/9/2010 |
Document, Report, or Work plan Review - other |
ADEC email to COE, EPA PM and Donna Baumler (USAF).
By outside sampling, you mean soil borings, monitoring well installation and associated soil/groundwater sampling? I would approve that portion (pending resolution of 1 issue below), with the understanding that the vapor intrusion work: soil gas sampling in the new building footprint area and associated buildings within 100 feet of ELM300 would be resubmitted under a separate work plan for EPA and ADEC comment and review.
One ADEC outstanding issue that needs resolution before approval for soil/groundwater focused sampling plan can be granted:
Use of PID
ADEC requests clarification on why the Air Force would PID screen if VOC samples are going to be collected every 5' per meeting notes recommendations.
ADEC is unclear on if PID field screening will be conducted, how will it be performed and an undisturbed, methanol preserved field sample still be collected. |
Louis Howard |
| 9/9/2010 |
Update or Other Action |
Amanda Heath (COE) sent email to ADEC, USAF. Per the comment below, field screening is a standard practice. However, VOC samples will be taken every five feet and PID sampling will be omitted from the SAP. |
Louis Howard |
| 9/9/2010 |
Document, Report, or Work plan Review - other |
Email from ADEC to COE, Jacques Gusmano (EPA) and Donna Baumler (USAF).
Pending any additional comments from EPA, ADEC is granting a one-time site-specific approval regarding VOC soil sampling procedure described below for the ELM300 project. It is expected that a separate sampling plan for vapor intrusion investigation at ELM300 will be submitted for review and comment at a later date. |
Louis Howard |
| 9/9/2010 |
Update or Other Action |
Email message to Jill Chouinard & Amanda Heath (COE), Donna Baumler & Gary Fink (USAF) and EPA Jacques Gusmano.
Here is what Elmendorf used at Operable Unit 6 for their soil boring screening and sampling procedures as part of the Management Plan Operable Unit 6. However, at DP98 (the last source area with major chlorinated solvents) they chose to sample every 2 ft. to 10' bgs in their soil borings or to groundwater (whichever occurred first) without field screening.
Take home message for everyone: One size does NOT fit all for field screening and soil borings methodology.
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Soil Sampling for Volatile Organic Analysis-Operable Unit 6: A total of four soil samples will be collected from each boring for laboratory analysis of volatile organic compounds. All soil samples that are recovered from the boring will be screened with an OVA and/or OVM.
The samples that are sent to the laboratory will be the following:
• The sample collected at the surface interval (0-2 feet); • The sample that displayed the highest OVA and/or OVM field screening results; • The sample corresponding to the deepest depth interval at which an OVA and/or OVM reading was obtained; and • The sample from the depth interval immediately below the depth at which the last deepest OV A and/or OVM reading was obtained.
At boring locations drilled through asphalt, soil samples for volatile organic analyses will not be collected from a depth shallower than 2 feet. The intent of this buffer interval below the asphalt layer is to minimize the potential for collecting soil samples which could be cross-contaminated with residual asphaltic organics.
An example of the soil sampling strategy for volatile organic compounds is included below. The following table represents the OV A and/or OVM readings obtained on seven hypothetical soil samples from a single boring:
Depth (Feet) OVA and/or OVM Reading
-------------------------------------
0-2' 0.1 ppm
4-5' 0.2 pppm
9-10' 1.2 ppm
14-15' 12.8 ppm
19-20' 8.5 ppm
24-25' 2.4 ppm
29-30' 0.0 ppm
34-35' 0.0 ppm
According to the above example, the soil samples that would be sent to the laboratory for VOC analysis would be those collected at the surface, at a depth interval from 14-15 feet (corresponding to the highest screening results), at a depth interval from 24-25 feet (the deepest screening results showing evidence of contamination), and at a depth interval from 29-30 feet (the sampling interval immediately below the last sample displaying evidence of contamination).
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DP98 Soil borings
Of the approximately 21 locations where near-surface soils will be sampled, those that exhibit chlorinated solvent contamination will be assumed to be contaminated at deeper depth as well. These areas will be excavated in 2005 from the surface to the vertical excavation limits. Those near-surface soils from which chlorinated solvents are not detected will be sampled at depth by advancing a soil boring to 10 bgs or groundwater, whichever is encountered first.
Starting at approximately 2 feet bgs, soil borings will be advanced using a direct push drill rig (e.g., geoprobe). Plastic sleeve liners will be used to collect continuous 5-foot soil cores, which will be logged and sampled every 2 feet. Up to five additional soil samples will be collected from each boring. Soil boring samples will be analyzed for chlorinated solvents on a standard turnaround time.
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SO in the case of ELM300, soil samples will be from each boring taken from 20' 25' 30' 35', 40' 45' 50'(at least seven samples ASSUMING groundwater is at 50' bgs) AT SD29 (formerly Hangar 15) the groundwater is at approximately 49 ft. bgs or as deep as 65' bgs (SEE table 3-7 from RI/FS for OU4)
This is not taking into account the required QC samples (refer to Table 4 Minimum Quality Control Scrutiny UST Procedure Manual).
-field duplicates (all soil/water samples), -decon/equipment blank (all soil water samples for sampling equipment decontaminated between samples, -Trip Blank (all water samples), -Methanol Trip Blank (all soil samples for VOCs) -Field Blank (used for highly contaminated sites with VOCs). |
Louis Howard |
| 9/10/2010 |
Update or Other Action |
Email from USAF (Donna Baumler) to ADEC, EPA and COE final work plan and response to comments.
ADEC requests clarification on why the Air Force would PID screen if VOC samples are going to be collected every 5' per meeting notes recommendations. ADEC is unclear on if PID field screening will be conducted, how will it be performed and an undisturbed, methanol preserved field sample still be collected.
Response: USACE – text will be changed to indicate that methanol preserved VOC samples will be collected every five feet; references to PID screening will be omitted.
All references related to soil gas and sub slab sampling will be removed; those efforts are no longer a part of this plan. |
Louis Howard |
| 9/13/2010 |
Update or Other Action |
EPA email to Gary Fink (USAF) and ADEC RE: ELM Hazardous Waste Determination
I have discussed the RCRA designation with Region 10 EPA. The TCE,PCE and Methylene Chloride found in the soil at ELM300 is an "F" listed Hazardous Waste as soon as it is excavated, as I discussed at our last meeting. It is "F" Listed because these constituents were used as degreasing agents. The only way to alter that determination is to petition to EPA for a "Contained in" Policy determination. This determination is made on a case by case basis and only by EPA. Data must be submitted that proves the material is not a risk as determined by EPA.
If you would like to petition for this finding, contact Cheryl Williams, RCRA Region 10, (206) 553-2137. I have alerted RCRA staff that the Air Force appears to be mis-informed about the "contained in " Policy and may have made the wrong assumptions in the past, on MILCON construction projects. |
Louis Howard |
| 9/30/2010 |
Update or Other Action |
This project was not intended to be a comprehensive environmental investigation of the site, & changes in the condition of the site may occur with time due to natural processes or human activities. The findings presented in this report are based on the soil boring data gathered at the time of the investigation. The third sampling event, a total of three borings (TB-3, TB-6 & TB-7) were drilled at the ELM300 site on 10, 11 & 17 September 2010.
The field crew over the course of this third event consisted of USACE geotechnical engineer Inocencio Roman, EIT Lance Overstreet, drillers Lyle Cain & Chris Bean (CEPOA-ES-SG), & USACE chemists Amanda Heath & Teresa Lee (CEPOA-EN-ESM).
During field activities for the third sampling event, refusal was encountered at TB-6 & TB-3 at a depth of 21.5 feet & 31.5 feet, respectively. The drill was advanced to a depth of 47 feet where refusal was encountered at TB-7. GW was not encountered. The soil samples collected from the borings were field-screened with a photoionization detector (PID).
During the third sampling event in September 2010, no visual evidence of chemical contamination was observed. However, due to the knowledge that the site is contaminated, all soil samples were segregated.
During the September 2010 sampling event, all soil cuttings were not returned to the boring. All soil cuttings were segregated into a 55-gallon drum left on site. Potable water was
used to hydrate the bentonite chips used to seal the borings or discarded on the ground near
the borings. Solid waste (i.e., disposable sampling equipment & other trash) was disposed
of in facility trash receptacles.
Summary
The test borings & laboratory testing results indicate soil contamination within the project limits as follows:
1. Arsenic was detected at levels above ADEC cleanup levels in most samples. These levels are above the ingestion contact limit of 5.5 mg/kg specified in 18 AAC 75.341, Table B-1 & are slightly below the background range determined for Fort Richardson & Elmendorf Air Force Base soils.
2. Benzo(a)pyrene was detected in one sample at a concentration greater than the ADEC ingestion level established in Table B-1 of 18 AAC 75.341.
3. DRO was detected in two samples & a duplicate at a concentrations greater than the ADEC migration to GW cleanup level, but well below the inhalation & dermal contact levels established in Table B-1 of 18 AAC 75.341.
4. Methylene chloride was detected in three samples at a concentration greater than the ADEC migration to GW cleanup level, but well below the inhalation & dermal contact levels established in Table B-1 of 18 AAC 75.341.
5. Tetrachloroethene (PCE) was detected in six samples at concentrations greater than the ADEC migration to GW cleanup level, but well below the inhalation & dermal contact levels established in Table B-1 of 18 AAC 75.341.
6. Trichloroethene (TCE) was detected in seventeen samples at concentrations greater than the ADEC migration to GW cleanup level, but below the inhalation & dermal contact levels established in Table B-1 of 18 AAC 75.341.
Recommendations- All contaminated soils shall be removed within the building footprint & project areas as defined in the project drawings & in strict accordance with the project specification sections.
To protect existing building foundations during the excavation, an excavation design by a licensed structural engineer shall be accomplished in accordance with project criteria & specifications.
The limit of the TCE/PCE plume was not determined. Therefore, additional sampling should be accomplished to determine the extents of the contamination plume.
A passive vapor mitigation system (similar to a radon mitigation system) shall be installed in the new facility as defined in the project specification section.
The contractor must be prepared to accomplish control measures to mitigate the site workers potential exposure to the reported contaminates & relevant exposure pathways (e.g. from fugitive dust, etc.). As a minimum, the contractor shall be in full compliance with all safety requirements specified in EM 385-1-1, “Safety & Health Requirements Manual”.
NOTE To file 1,1,2,2-Tetrachloroethane Method 2 cleanup level migration to GW is 0.17 mg/kg. Report states N.D. or not detected, however the detection limit is above the cleanup level in the samples: e.g. 10ELM300C3 TB-3 19.5' - 21.5' 0.0493 mg/kg, 10ELM300D3 24.5' - 26.5' 0.0495 mg/kg & 10ELM300E3 0.492 mg/kg. Same issue with 1,1,2-Trichloroethane which has a cleanup level of 0.018 migration to GW & the detection limit for the same samples are 0.247 mg/kg, 0.248 mg/kg & 0.246 mg/kg & 1-2 Dichloroethane (cleanup is 0.016 mg/kg) detection limit 0.247 mg/kg, 0.248 mg/kg & 0.0246 mg/kg. respectively. This elevated detection limits above cleanup levels was an issue in the February & July 2010 sampling events. |
Louis Howard |
| 10/27/2010 |
Update or Other Action |
Subject Draft Approval Memorandum for Non-Time-Critical Engineeering Evaluation/Cost Analysis at F-22 Weapons Release Shop (Building 17720)
This Approval Memorandum documents the 673d Air Base Wing’s decision to prepare an Engineering Evaluation/Cost Analysis (EE/CA) to evaluate remediation of the F-22 Weapons Release Shop (Building 17720) site located on Joint Base Elmendorf-Richardson (JBER)-Elmendorf, Alaska through the use of a Non-Time-Critical Removal Action. The proposed EE/CA would evaluate options to address subsurface soil contaminated with benzo(a)pyrene, diesel-range organics (DRO), methylene chloride, trichloroethylene (TCE), and tetrachloroethylene (PCE). The presence of these contaminants, and the subsequent threat posed to human health and the environment, satisfies the National Oil and Hazardous Substances Pollution Contingency Plan criteria to initiate a non-time-critical CERCLA response action. Activities described in this approval memorandum will be performed in accordance with Cercla (42 USC 9601) and the NCP (40 CFR Part 300).
An EE/CA will be performed to evaluate suitable alternatives to address contamination at Bldg. 17720. The proposed project objectives of this EE/CA is to investigate and further characterize the nature and extent of environmental contamination present at the site and to follow a NTC CERCLA process through the completion of an EE/CA. A streamlined risk evaluation will be conducted to assess the potential risk of exposure to contamination. In performing the risk evaluation, the need for conducting a removal action will be determined and removal action objectives will be identified. The selected alternative to address contamination at the site will be described in an Action Memorandum that will incorporate, as appropriate, regulatory agency and public comments.
Substances Pollution Contingency Plan (NCP) criteria to initiate a Non-Time-C
Comprehensive Environmental Response, Compensation, and Liability Act (CERCL
action. Activities described in this Approval Memorandum will be performed i
CERCLA (42 USC §9601) and the |
Louis Howard |
| 10/27/2010 |
Update or Other Action |
F-22 Weapons Release Shop NTC EE/CA Technical Memorandum (Draft) received. This Technical Memorandum describes the field activities planned at the F-22 Weapons Release Shop (Building 17720) site at Joint Base Elmendorf Richardson (JBER)-Elmendorf, Alaska & serves as an addendum to the Fort Richardson Post Wide Work Plan (U.S. Army Engineer District, Alaska .
The primary objective of this investigation is to characterize the nature & extent of environmental contamination present at the site & to follow a Non-Time-Critical CERCLA process through the completion of an Engineering Evaluation/Cost Analysis (EE/CA).
Soil borings will be advanced at 18 locations around the Building 17720 expansion area to investigate subsurface soil contamination. These boring locations were determined based on previous drilling & site investigation results, proposed construction activities, current site features, & GW gradient. Well locations are generally aligned with the GW direction at the site & are spaced approximately 10 feet apart. Soil boring locations may be modified based on the site conditions, evidence of contamination, & utility conflicts.
Several soil borings will be advanced to GW. GW at the site is anticipated between 50 & 60 feet bgs. Samples will be collected from the soil boring in accordance with Appendix B, Section 3.1 of the Fort Richardson Post Wide Work Plan, with the following exceptions:
• Soil screening will be performed using a PID twice along each 5-foot core section. Three samples will be collected from each boring. The analytical samples will represent the areas of highest contamination as identified by PID field screening.
• Decontamination blank samples will be collected at a frequency of one per every twenty soil borings. These samples will be collected from deionized water used as a final rinse of the drilling equipment. Decontamination blank samples will be analyzed for the same analyses as the primary samples.
Boreholes for the well points will be drilled via direct-push using open single tube tooling (Geoprobe® 8040 or similar) to minimize compaction due to soil displacement. The locations for the borings were determined based on sampling results from previous investigations .
For each soil boring, one surface soil sample & three subsurface soil samples will be sent to a fixed lab for analysis. If the boring is advanced to GW, a water sample will be sent to the fixed lab for analysis.
Using the same 3.25-inch drill rod as the DT325 outer casing, RS60 tooling cuts a 2.36-inch diameter core instead of a 1.80-inch diameter core, displacing approximately 30 percent less soil. Minimizing compaction will maximize GW flow into the temporary well point. Temporary well points will be constructed using new 1-inch Schedule-40 polyvinyl chloride (PVC) 0.010-inch slotted screen & riser (large enough for a 0.75-inch bailer).
Drilling will proceed to approximately 5 feet below the water table. If the hole stays open to at least 2 feet below the water table after the drill string is pulled, the well point will be placed in the uncased hole. If the hole closes up, it will be re-cored using dual-tube tooling. After coring, the cutting shoe will be cleared with a solid drive point, allowing the 1-inch PVC screen to pass through the shoe & stay in place as the outer casing is raised to the water table. Although specialized direct-push tooling for water sampling is available (e.g., the Geoprobe® SP16 system), its small diameter seems unlikely to produce sufficient water; therefore, temporary well points will be utilized.
Finally, soil gas samples will be collected from two of the existing well point borings from within the proposed building footprint. These soil gas samples will be collected at 4 feet bgs & will be compared to ADEC commercial screening levels (ADEC 2009).
COCs near Building 17720 are GRO, DRO, RCRA metals, VOCs, & PAHS for subsurface soil samples & GW samples. In addition to these COCs, the surface soil samples will also be analyzed for PCBs, pesticides, & RRO. Cleanup levels will be based on ADEC Method Two migration to GW under 40-inch zone. The most stringent levels will be used: migration to GW for petroleum hydrocarbons & ADEC Shallow, Indoor Air, or Subslab Soil Gas Screening Levels/Commercial Scenario where appropriate for the remaining COCs. Lab-based reporting limits will be used for VOCs & soilgas samples when ADEC cleanup levels or screening values are not available.
One surface soil sample will be collected from each of the 18 soil boring locations. These 18
locations are based on previous drilling & sample results near Building 17720, the building
footprint for future construction, & the existing GW gradient at the site.
Surface samples will be analyzed for the following analytes:
• GRO by AK101
• DRO/RRO by AK102/AK103
• RCRA Metals by SW6020/SW7471
• PCBs by SW8082 |
Louis Howard |
| 10/29/2010 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the Draft F-22 Weapons Release Shop (ELM300) Work Plan Addendum
Drilling Approach Page 7
Field screening with a PID will guide sampling efforts, but will not serve as a substitute for definitive laboratory analytical results in determining whether or not contamination is present in the soil above cleanup levels. In no case shall the Air Force fail to collect the minimum number of samples from each boring due to lack of field screening results (i.e. 0 ppm or PID screening results are all below a certain ppm threshold). In this case, best professional judgment by the sampling technician will be used to collect the mandatory number of samples from each boring (one surface soil sample and three subsurface soil samples).
When groundwater is encountered, at least one of the subsurface soil samples must be collected from the first six inches of groundwater-saturated soil or the zone of seasonal water table fluctuation.
Page 10
Drilling Approach
The Air Force shall be prepared for alternative drilling techniques (i.e. Air Rotary rig) should the Geoprobe 8040 or similar apparatus not be successful at reaching groundwater during this investigation in order for groundwater samples to be obtained for this project.
Page 8
ADEC Field Sampling Guidance: Peristaltic pumps and bailers are NOT the preferred method for the collection of volatiles or other air sensitive parameters. Rather the use of bladder pumps, positive pressure submersible pumps, gear pumps, passive diffusion bag samplers, or samplers like HydraSleeve or Snap Samplers are preferred to reduce the loss of volatiles during sampling. Please note the temporary well groundwater data obtained during this field effort will be treated as "screening level data" versus groundwater data obtained from permanent monitoring wells
Commercial/industrial levels can be used when contamination is near buildings occupied by workers that are present for a standard work week (8-10 hours per day, 5 days a week) OR LESS. If individual workers are present for more than a standard work week, or if sensitive receptors are present, DEC may require use of the residential level or development of a site-specific target level.
Page 11
Vapor Intrusion Sampling
ADEC VI Guidance (July 2009): "When deciding on soil gas sample locations, the investigator should consider the location of releases, other potential vapor sources, preferential pathways (e.g., utilities or sumps entering a building), and lithology. A sufficient number of samples should be collected to represent the maximum vapor concentrations that could impact the current or FUTURE occupied structures. At least THREE locations should be sampled per building with one in the area of the highest soil or groundwater contamination near or beneath the building."
1) ADEC requests the Air Force either take three subslab samples from Building 17720 or take the planned two subslab samples from Building 17720 and one soil gas sample in the area of highest soil or groundwater contamination near or beneath building 17720.
2) ADEC requests the Air Force utilize THREE distinct soil borings within the proposed construction footprint which would be six soil gas samples instead of the proposed four soil gas samples.
3) Finally, based on the square footage of Building 17720, two indoor air samples may not be enough (especially if the building is over 2000 sq. ft.). ADEC VI Guidance states: "DEC recommends collecting at least one [1] indoor air sample per 1,000 square feet of floor space. Larger buildings may require additional samples, especially if they contain separate air spaces or air-handling units."
The Lab Data Review Checklist for Air Samples (January 2010) will be a requirement for the ELM300 Project. This checklist for air samples is in addition to the other required Lab Data Review Checklist for soil and groundwater samples (January 2010 version 2.7) |
Louis Howard |
| 10/29/2010 |
Document, Report, or Work plan Review - other |
ADEC has the following comments on the October 27, 2010 F-22 Weapons Release Shop Non-Time-Critical Engineering Evaluation/Cost Analysis Technical Memorandum (Draft).
Drilling Approach-Soil Boring Investigation Page 7 of 18
The text states:
Soil screening will be performed using a PID twice along each 5-foot core section. Three samples will be collected from each boring. The analytical samples will represent the areas of highest contamination as identified by PID field screening.
Samples will be collected for the analyses listed in Table 2.
Field screening with a PID will guide sampling efforts, but will not serve as a substitute for definitive laboratory analytical results in determining whether or not contamination is present in the soil above cleanup levels. In no case shall the Air Force fail to collect the minimum number of samples from each boring due to lack of field screening results (i.e. 0 ppm or PID screening results are all below a certain ppm threshold). In this case, best professional judgment by the sampling technician will be used to collect the mandatory number of samples from each boring (one surface soil sample and three subsurface soil samples). When groundwater is encountered, at least one of the subsurface soil samples must be collected from the first six inches of groundwater-saturated soil or the zone of seasonal water table fluctuation.
The text states: "Boreholes for the well points will be drilled via direct-push using open single tube tooling (Geoprobe(r) 8040 or similar) to minimize compaction due to soil displacement."
The Air Force shall be prepared for alternative drilling techniques (i.e. Air Rotary rig) should the Geoprobe 8040 or similar apparatus not be successful at reaching groundwater during this investigation in order for groundwater samples to be obtained for this project.
Vapor Sampling Page 11 of 18
The text states: "Vapor sampling includes the collection of two interior air samples and two subslab samples from Building 17720. In addition, two soil gas samples will be collected from two distinct borings within the proposed construction footprint. These locations will be determined based on field screening and analytical sample results."
ADEC VI Guidance (July 2009): "When deciding on soil gas sample locations, the investigator should consider the location of releases, other potential vapor sources, preferential pathways (e.g., utilities or sumps entering a building), and lithology. A sufficient number of samples should be collected to represent the maximum vapor concentrations that could impact the current or FUTURE occupied structures. At least THREE locations should be sampled per building with one in the area of the highest soil or groundwater contamination near or beneath the building."
ADEC requests the Air Force either take three subslab samples from Building 17720 or take the planned two subslab samples from Building 17720 and one soil gas sample in the area of highest soil or groundwater contamination near or beneath building 17720.
ADEC requests the Air Force utilize THREE distinct soil borings within the proposed construction footprint which would be six soil gas samples instead of the proposed four soil gas samples.
Finally, based on the square footage of Building 17720, two indoor air samples may not be enough (especially if the building is over 2000 sq. ft.). ADEC VI Guidance states: "DEC recommends collecting at least one [1] indoor air sample per 1,000 square feet of floor space. Larger buildings may require additional samples, especially if they contain separate air spaces or air-handling units." |
Louis Howard |
| 10/29/2010 |
Document, Report, or Work plan Review - other |
EPA Jacques Gusmano sents email message to ADEC, USAF.
Donna, I agree with the ADEC comments. Use of the PID screening is even more doubtful when soils are frozen. Field personnel need to take good field notes on location decisions for soil depth samples. |
Louis Howard |
| 11/1/2010 |
Document, Report, or Work plan Review - other |
Email sent to USAF, and EPA PMs.
The Lab Data Review Checklist for Air Samples (January 2010) will be a requirement for the ELM300 Project. This checklist for air samples is in addition to the other required Lab Data Review Checklist for soil and groundwater samples (January 2010 version 2.7). |
Louis Howard |
| 11/2/2010 |
Document, Report, or Work plan Review - other |
Air Force comments to the Corps of Engineers on the Draft F-22 Weapons Release Shop (ELM300) Work Plan Addendum. Drilling and Sampling Approach (Provided during ELM300 regulator meeting on 10/27/2010).
We would like to focus on delineating the nature and extent of contamination in the proposed building expansion footprint. Additional samples shall be collected to delineate the extent of vertical contamination beneath the proposed building footprint.
All borings do not need to be advanced to groundwater at the site. Borings should either be advanced to groundwater or to 40 feet bgs. Samples should focus on vertical delineation at the site.
Response: Based on the October 27 meeting, a higher sample density will be collected from the soil borings within the proposed building footprint (particularly from the 2 to 15 feet bgs zone). Additional borings will be drilled within the building footprint.
The following text will be added to page 10, 3rd paragraph:
“To provide increase resolution of potential contamination within the proposed building expansion footprint, five samples will be collected from the borings at the following intervals: 4 to 6 feet, 8 to 10 feet, 12 to 14 feet, 20 to 30 feet, and 30 to 40 feet bgs.”
The following text will be added to page 10, Subsurface Field Screening and Analytical Sampling: “Eighteen soil borings will be drilled to at least 40 feet bgs. Nine of those will be advanced to groundwater (50 to 60 feet bgs). A minimum of five samples will be collected and analyzed from each boring within the proposed building expansion footprint, and a minimum of three subsurface samples will be collected from each boring outside the footprint.”
|
Louis Howard |
| 11/2/2010 |
Document, Report, or Work plan Review - other |
Corps of Engineers response to EPA comments on the Draft F-22 Weapons Release Shop (ELM300) Work Plan Addendum.
Response: Based on the October 27 meeting, a higher sample density will be collected from the soil borings within the proposed building footprint (particularly from the 2 to 15 feet bgs zone). All proposed soil samples will be collected at the specified frequency even if the PID does not indicate contamination.
The following text will be added to page 10, 3rd paragraph:
“To provide increase resolution of potential contamination within the proposed building expansion footprint, five samples will be collected from the borings at the following intervals: 4 to 6 feet, 8 to 10 feet, 12 to 14 feet, 20 to 30 feet, and 30 to 40 feet bgs. PID screening will occur along the cores, but analytical sample locations will not always rely on PID results. Samples will be collected at the specified frequency regardless of PID response. If PID screening is indeterminate, then an analytical sample will be collected from the center of the interval. All samples will be discrete samples.”
|
Louis Howard |
| 11/5/2010 |
Document, Report, or Work plan Review - other |
Email message sent to USAF.
ADEC has reviewed all the response to comments on the work plan addendum and they did not conflict with ADEC's comments. ADEC will grant approval on the response to ADEC comments and the work plan addendum can be finalized. |
Louis Howard |
| 11/5/2010 |
Update or Other Action |
Response to comments received from the USAF. Based on the October 27 meeting, a higher sample density will be collected from the soil borings within the building footprint (particularly from the 2 to 15 feet bgs zone). All proposed soil samples will be collected at the specified frequency even if the PID does not indicate contamination.
The following text will be added to page 10, 3rd paragraph:
“To provide increase resolution of potential contamination within the proposed building expansion footprint, five samples will be collected from the borings at the following intervals: 4 to 6 feet, 8 to 10 feet, 12 to 14 feet, 20 to 30 feet, and 30 to 40 feet bgs.
PID screening will occur along the cores, but analytical sample locations will not always rely on PID results. Samples will be collected at the specified frequency regardless of PID response. If PID screening is indeterminate, then an analytical sample will be collected from the center of the interval. All samples will be discrete samples “
The sampling approach for soil borings advanced to groundwater will be modified to include sampling from the upper six inches of the saturated zone. The following text will be added to page 10, 2nd paragraph:
“For soil borings advanced to groundwater, one sample will also be collected from the first six inches of the saturated zone.“
Recent drilling in the vicinity of Building 16716 did not encounter refusal and reached groundwater at 51 feet bgs with a 6000 series Geoprobe direct push drill rig. Jacobs will notify the USAF if refusal is encountered while trying to reach groundwater at the site.
The groundwater sample results will be considered screening level data.
Vapor intrusion sample data will be compared to the more stringent residential screening levels for risk evaluation.
1) The number of subslab sampling plan for Building 17720 will be left as planned (two subslab samples). The soil boring location at the south east corner of Building 17720 (near the storage shed) will be completed as a soil vapor sampling point. Historical analytical results show the highest VOC contamination present in this area. Soil gas samples will be collected from this location at 5 feet bgs and 15 feet bgs.
The following text will be added to page 11, 2nd paragraph:
“In addition, soil gas samples will be collected from each of three distinct borings within or directly adjacent to the proposed construction footprint and one boring adjacent to Building 17720(Figure 2). Vapor samples will be collected from 4 and 15 feet bgs from the selected locations according to the procedures...”
2) See response to 1) directly above.
3) The building is approximately 5000 square feet in size. The text will be revised to state: “Building 17720 measures approximately 5,000 square feet. A total of 5 indoor air samples will be collected.”
The specified checklists will be filled out during the evaluation of laboratory results. |
Louis Howard |
| 12/14/2010 |
Update or Other Action |
Final Approval Memorandum received for ELM300 Non-Time Critical Removal Action. This Approval Memorandum documents the 673d Air Base Wing’s decision to prepare an Engineering Evaluation/Cost Analysis (EE/CA) to evaluate remediation of the F-22 Weapons Release Shop (Building 17720) site located on Joint Base Elmendorf-Richardson (JBER)- Elmendorf, Alaska through the use of a Non-Time-Critical Removal Action. The proposed EE/CA would evaluate options to address subsurface soil contaminated with benzo(a)pyrene, diesel-range organics (DRO), methylene chloride, trichloroethylene (TCE), & tetrachloroethylene (PCE).
The presence of these contaminants, & the subsequent threat posed to human health & the environment, satisfies the NCP criteria to initiate a Non-Time-Critical CERCLA response action. Activities described in this Approval Memorandum will be performed in accordance with CERCLA (42 USC §9601) & the NCP (40 Code of Federal Regulations [CFR] Part 300). A site investigation will be performed in order to develop the EE/CA. The primary objective of this investigation is to characterize the nature & extent of environmental contamination present at the site & to follow a Non-Time-Critical CERCLA response action through the completion of an EE/CA. This Memorandum also opens an administrative record for information supporting selection of the remediation methodology.
The proposed expansion of the Weapons Release Shop (Building 17720) is located on the west side of Talley Avenue, on JBER-Elmendorf, AK . Site boundaries include Building 17726 to the west & Hangar 15 (Building 16716) to the southwest. The proposed addition to Building 17720 is located directly to the north of the existing Weapons Maintenance Shop (Building 16718) & west of Building 17720. Building 16718 has been used for the maintenance of equipment since it was built in the 1950s.
The site of the proposed building addition consists of a 20,000 square foot grassy area containing a small storage building (Building 17722) & the loading dock of Building 17720. Building 17722, thought to be formerly used as a solvent storage building, is scheduled for demolition prior to construction of the Building 17720 expansion. Building 17722 is just east of the footprint of the Building 17720 expansion site. According to the building operations & maintenance personnel, solvents are no longer stored in this area & no floor drains have been found.
Soil contamination has been confirmed at Building 16716, also known as Hangar 15. This building is located to the southwest of the project site & is used for aircraft maintenance. According to onsite personnel, chemicals & solvents were thought to have been disposed of in floor drains that led to dry wells at Building 16716. GW continues to be monitored as part of the remedy selected for SD29. For SD29, the complete remedy is documented in the Operable Unit 4 (OU4) Record of Decision (USAF 1995). In addition, a 20,000-gallon underground heating oil tank (HOT) was removed in 2003, along with 225 tons of petroleum, oil, & lubricants (POL)-contaminated soil, directly to the east of Building 16716. Additional fuel contaminated soils were left in place under the building.
An EE/CA will be performed to evaluate suitable alternatives to address contamination at Building 17720. The proposed project objective of this EE/CA is to investigate & further characterize the nature & extent of environmental contamination present at the site & to follow a Non-Time-Critical CERCLA process through the completion of an EE/CA. A streamlined risk evaluation will be conducted to assess the potential risk of exposure to contamination. In performing the risk evaluation, the need for conducting a removal action will be determined & removal action objectives will be identified. The selected alternative to address contamination at the site will be described in an Action Memorandum that will incorporate, as appropriate, regulatory agency & public comments. The EE/CA & Action Memorandum will be subject to the CERCLA CRP requirements for stakeholder notifications & involvement.
The CERCLA process requires preparation & public review of an EE/CA before preparation of the Action Memorandum that will document official selection of the NTCRA alternative. The preliminary cost estimate to address contamination at Building 17720 will be developed as part of the EE/CA, as will the project schedule.
Approval is hereby given to conduct an EE/CA for the ELM300 on EAFB, AK. The NTCRA & associated activities will be conducted in accordance with the relevant requirements of the NCP (40 CFR 300) & pursuant to Section 104 of CERCLA (42 USC (SYMBOL) 9604). A signed action memorandum will be required as authorization to proceed with removal & disposal at ELM300. The completed EE/CA will be made available for public review & comment. |
Louis Howard |
| 3/2/2011 |
Update or Other Action |
Draft EE/CA received for F-22 Weapons Release Shop (Bldg. 17720) on JBER-Elmendorf. The purpose of this EE/CA is to present & evaluate alternatives to remediate contaminated soil at the F-22 Weapons Release Shop (Building 17720) at Joint Base Elmendorf-Richardson (JBER-Elmendorf), Alaska. These alternatives address potential risks posed by contaminated soil. Decisions on how to address this contamination will be made under the CERCLA NTCRA rules.
COCs at the site include diesel-range organics (DRO), trichloroethene (TCE), & tetrachloroethene (PCE). The extent of DRO contamination in soil is limited & at low concentrations relative to Alaska Department of Environmental Conservation (ADEC) standards. It is anticipated that the DRO-contaminated soil will be removed during planned building construction. Thus, this EE/CA focuses on alternatives to address TCE & PCE contamination.
The potential risks associated with the direct contact, outdoor air inhalation, migration to GW & GW ingestion exposure pathways have been considered based on a comparison between contaminant concentrations detected in site soils & published standards. The potential risks associated with indoor air inhalation was assessed using the Johnson & Ettinger model.
PCE presents a potentially unacceptable risk via the migration to GW exposure pathway; TCE presents a potentially unacceptable risk via the outdoor air inhalation, migration to GW, & indoor air inhalation exposure pathways. DRO presents a potentially unacceptable risk via the migration to GW/GW ingestion exposure pathway.
The following remedial action objectives (RAO) were developed to guide the development of alternatives:
• Reduce risk to human health & the environment by eliminating the human health hazards associated with contaminated subsurface soil, groundwater, & vapor.
• Mitigate an imminent & substantial endangerment to public health, welfare & the environment by preventing TCE-contaminated vapor above 100 µg/m3, identified by the Johnson Ettinger Model, from intruding into existing structures.
• Mitigate an imminent & substantial endangerment to public health, welfare, & the environment by preventing contaminated soil above the most stringent ADEC Method Two migration-to-GW cleanup levels from contaminating GW.
• Prevent ingestion of DRO-contaminated GW at concentrations above the ADEC Table C GW cleanup level of 1.5 mg/kg.
• Maintain the planned construction schedule at the site.
• Comply with applicable federal, state, & local laws & regulations.
Alternative 6: In Situ Treatment of Contaminated Soil & Excavation (the preferred alternative)
Alternative 6 incorporates minimal excavation for utilities & the proposed building foundation, a vapor barrier under the new structure, & installation of a soil vapor extraction (SVE) treatment system to remediate subsurface TCE & PCE contamination. Under this alternative, approximately 6,000 cy of contaminated soil would be generated during utility & building footer excavation. The contaminated soil would be containerized & transported off site for treatment/disposal. The extent of excavation is detailed under Alternative 3. In addition to excavation, a vapor barrier would then be placed across the site.
To treat contamination under existing buildings, an SVE system would be designed, constructed & operated. The SVE system would require the installation of extraction wells, piping, a blower, & an effluent vent. The wells would be placed at the site according to contaminant levels & at spacing defined by the zone of influence to effectively remediate subsurface contamination. The system would be expected to operate for a period of 2 years.
Alternative 6 includes the excavation proposed in Alternative 3 plus the installation & operation of an SVE system. This combination would effectively address risks posed by site contamination. The SVE system would treat residual contamination beneath the footprint of the proposed building & beneath existing buildings. Compared with the other alternatives, Alternative 6 would treat a larger volume of contamination. However, the construction of the SVE system would have to be integrated with building construction, posing an implementability challenge. Alternative 6 would be slightly more expensive than Alternative 3, but less expensive than Alternatives 4 or 5.
Alternative 6 would cost 2.2 million vs. 4.6 million for Alternative 5 (Maximum Excavation & Vapor Barrier Installation) & 2.7 million for Alternative 4 (Uniform Excavation with Sub-Slab Depressurization System)or 1.8 million for Alternative 3 (Minimal Excavation with Sub-Slab Depressurization System). Alternative 2 (Sub-Slab Depressurization & Vapor Barrier Installation)would cost 0.3 million.
|
Louis Howard |
| 3/4/2011 |
Site Added to Database |
A new site has been added to the database |
Mitzi Read |
| 3/4/2011 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 79047 name: Bldg 17720 F-22 Weapons Release Shop |
Mitzi Read |
| 3/25/2011 |
Document, Report, or Work plan Review - other |
Staff reviewed & commented on the 2011 Engineering Evaluation/Cost Analysis F-22 Weapons Release Shop, Draft JBER, Alaska received on February 28, 2011.
Executive Summary Page ES-1 First Para.
ADEC requests the AF state the non-time critical removal action will address the contaminated soil associated with the F-22 Weapons Release Shop during the planned building construction footprint. After the non-time critical removal action is complete, it is likely the source area will require additional action to determine the full nature & extent of the threat to the public health or welfare or the environment caused by the release or threatened release of hazardous substances, pollutants, or contaminants beyond the building footprint.
ADEC is requesting the AF amend the 1991 Elmendorf FFA to include the F-22 Weapons Release Shop as a new source area.
ADEC views the non-time critical removal action as a removal defined by Section 101(23) of CERCLA, 42 U.S.C. § 9601(23). Removal shall mean: the cleanup or removal of released hazardous substances from the environment; such actions as may be necessary in the event of the threat of release of hazardous substances into the environment; such actions as may be necessary to monitor, assess, & evaluate the release or threat of release of hazardous substances; the disposal of removed material; or the taking of such other actions as may be necessary to prevent, minimize, or mitigate damage to the public health or welfare or to the environment that may otherwise result from a release or threat of release.
It is anticipated a permanent remedy or remedial action will be taken at this source area as required by the 1991 FFA. A remedial action is defined in 40 CFR 300.5 & shall mean those actions consistent with permanent remedy taken instead of, or in addition to, a removal action in the event of a release or threatened release of a hazardous substance into the environment, to prevent or minimize the release of hazardous substances so that they do not migrate to cause substantial danger to present or future public health or welfare or the environment.
Contaminants of Concern Page ES-2
ADEC requests the AF elaborate more in this section on what media the TCE & PCE has contaminated. Also, ADEC requests the AF state whether or not the DRO contamination exceeds cleanup level instead of stating “...at low concentrations relative to….”
Removal Action Scope & Alternatives Pages ES-2 & ES-3
In accordance with § 300.430 Remedial investigation/feasibility study & selection of remedy (e) Feasibility Study(2)(i) – “In developing &, as appropriate, screening the alternatives, the lead agency shall: (i) Establish remedial action objectives specifying contaminants & media of concern, potential exposure pathways, & remediation goals.”
Maintaining a construction schedule is not an RAO nor is complying with federal, state, local laws & regulations. Complying with ARARs is one of the nine criteria for evaluation & analysis of alternatives under review. Or in the case of Removal Action the three criteria: Effectiveness, Implementability & Cost. ADEC requests the AF delete reference to maintaining construction schedule & complying with federal, state, local laws & regulations when discussing RAOs in this document.
Analysis of Alternatives Page ES-5
Alternative 2
The text states: “However, it would prevent construction of the proposed building according to the present design. It may be possible to re-design the proposed building, but construction would not be possible within the current schedule.”
ADEC requests the AF delete the two sentences for Alternative 2 since preventing construction of a proposed building according to a design or staying within a current schedule is not appropriate in the analysis of alternatives.
Alternative 3
The text states: “Alternative 3 is the least expensive alternative that would address contaminant risks & allow on-time construction of the proposed building.”
ADEC requests the AF simply state: “Alternative 3 is the least expensive alternative that would address contaminant risks.” since allowing for on-time construction of a proposed building is not appropriate in the analysis of alternatives.
Preferred Alternative Pages ES-6 & ES-7
ADEC requests the AF simply state: “The proposed solution is implementable.” Whether or not it would delay a construction of a building is not part of the detailed analysis of alternatives using the three criteria to pick a preferred alternative.
The paragraph on Page ES-7 states: “An option for onsite treatment of the PCE- & TCE-contaminated soil was also considered.” This statement should not be in the preferred alternative section. ADEC requests the AF delete this sentence from the paragraph & either drop it from the document or add it as another alternative in the Detailed Analysis of Alternatives section.
See site file for additional information. |
Louis Howard |
| 3/31/2011 |
Document, Report, or Work plan Review - other |
EPA's comments on the EE/CA.
1. The Draft 2011 Engineering Evaluation/Cost Analysis, F-22 Weapons Release Shop, dated Feb. 2011 doesn't present data which supports the depicted horizontal & vertical extent of contamination in surface soil, subsurface soil & GW in Fig. 2-1, Bldg. 17720, Extent of Contamination. The limits do not appear to be based on a straight-line interpolation of the results above assessment levels versus levels below assessment levels.
Data to support the known areas of contamination need to be provided to support the established contaminant limits, or the alternatives presented need to include refinement of the known extent of contamination as an initial step. Please revise to justify the selection of the boundaries of the areas of contamination for trichloroethylene (TCE), tetrachloroethylene (PCE), & diesel range organic (DRO) contamination, or to recommend additional sampling to completely define the vertical & horizontal extent of contamination.
2. Fig. 2-1 depicts eight areas of TCE/PCE contamination in soil & GW, but the plumes are not bounded by sample results in all cases. For example, the area of contamination depicted at boring TB-4 & boring to GW location “18” are not bounded in any direction by sample results. Further the report text indicates in Sect. 2.7 that this discontinuous contaminant interpretation is due to the occurrence of “multiple, small releases”.
An alternate rationale for the discontinuous appearance of the releases could be the extended freeze thaw cycle & inter-bedded layers of fine grained & course grained soils. These two conditions could serve to mask the conditions to make it appear as if the releases are discontinuous. The more conservative interpretation would be to assume that they are all one continuous plume in lieu of a more documented release pathway. Please revise to either justify via establishment of known release points the discontinuous nature of the plumes or revise the interpretation to indicate that one plume of constituents exists with localized hot spots.
3. The Draft EE/CA doesn't justify excluding certain analytes detected above action levels from the list of COCs presented in the Executive Summary. For example,
a. Table 2-3, Subsurface Soil Exceedance Summary, indicated exceedances of benzo(a)anthracene, benzo(a)pyrene, benzo(b) fluoranthene, dibenzo[a,h]anthracene, & methylene chloride. Sect. 2.6.2 states that detections of methylene chloride in subsurface soil samples “appear to be the result of laboratory contamination.” However, several methylene chloride results presented in Attach. C-3 do not have “B” qualifiers to indicate that they were subject to blank contamination. Further, benzo(a)pyrene & methylene chloride was detected during previous investigations as noted in Table 2-1.
b. Table 2-4, GW Exceedance Summary, indicated exceedances of polycyclic aromatic hydrocarbon compounds (PAHs) & metals. Sect. 2.6.3 states that GW exceedances for the PAHs & metals are not representative of dissolved-phase contaminants because of introduction of fine soil particles during sample collection. However, this assumption is not justified.
c. Sect. 2.1.1 of App. C, Data Quality Assessment, states that several analytes were reported as non-detect where the detection level was greater than the action level. No justification has been provided to exclude them as COCs. Results from other samples suggest that methylene chloride may be a COC at this location. Vinyl chloride is a break-down product of PCE & TCE could be present near areas of PCE & TCE contamination.
Please revise to justify the exclusion of these compounds from consideration as COCs.
4. The discussion of remedial action objectives (RAOs) presented in Section 4.2, Remedial Action Objectives, lacks sufficient detail. RAOs should specify the contaminants & media of interest, exposure pathways, & preliminary remedial goals (PRGs) that permit a range of treatment & containment alternatives to be developed. However, 4 of the 6 RAOs listed in Sect. 4.2 are not specific. The contaminants, media of interest, exposure pathways, & PRGs that require development of a range of alternatives to be developed have not been adequately identified.
As such, it is unclear if the alternatives developed are appropriate. In addition, the RAOs do not specifically address PCE even though it is shown to be a risk driver. Revise to provide clearly defined RAOs that specify the contaminants & media of interest including PCE, exposure pathways, & PRGs that permit a range of alternatives to be developed. Additionally, it is unclear what the basis is for the RAO of “maintain the planned construction schedule at the site.” Without further justification, this RAO is inappropriate. Please either revise to either justify or remove this RAO.
See site file for additional information. |
Louis Howard |
| 5/13/2011 |
Update or Other Action |
Staff received the draft Design & Construction Work Plan (WP) Addendum includes the design approach & the construction execution plan for remediation at a proposed expansion site adjacent to Building 17720 at the F-22 Weapon Release Shop (the “site”) at Joint Base Elmendorf-Richardson (JBER).
Fieldwork at the site will be completed in July 2011 to allow a programmed MILCON project to construct a new building adjacent to Building 17720. The remediation activities planned at the site include the excavation of soils contaminated with diesel-range organics (DRO), polycyclic aromatic hydrocarbons (PAH) trichloroethene (TCE), & tetrachloroethene (PCE) to a point just below the foundation of the new building addition so that the MILCON project workers do not disturb other potentially affected soils.
The DRO- & PAH-contaminated soils will be transported for offsite treatment & disposal locally, while the nonhazardous TCE- & PCE-contaminated soils will be placed in a lined, covered, & actively ventilated stockpile; any soils containing RCRA hazardous waste will be containerized at the excavation & transported to a licensed & permitted RCRA Subtitle C treatment, storage, & disposal facility (TSDF).
The remaining contamination in soils at the site will be treated in situ through the use of a soil vapor extraction (SVE) system. The design for this system includes blower sizing & extraction well spacing for a radius of influence (ROI) sufficient to provide remediation of the solvent contamination within approximately 2 yrs of system start-up. A skid-mounted blower system will be installed near the northwest corner of Building 17720. All SVE piping will be installed in trenches approximately 10’ bgs & covered with concrete to permit subsequent construction of the proposed building addition.
This Design & Construction WP is an addendum to the 2010 Fort Rich Post Wide WP (USACE 2010c) & as such references this Post Wide WP while focusing on site-specific requirements & providing additional details necessary to complete these activities in a safe & efficient manner.
An estimated 2,100 cy of non-compacted soil contaminated with DRO, PAHs, PCE, & TCE above ADEC cleanup limits will be excavated from the site & consolidated in a ventilated stockpile to remove PCE & TCE. The final excavated volume of soil may vary; as a result, the vented pile design allows for expansion or reduction as needed. The area selected for the pile construction is flat, & is currently a well-drained grass & gravel area with electrical power available at the west end. The soil venting pile footprint will be approximately 100’ by 100’; the pile is anticipated to have a maximum height of approximately 6’.
The contaminated soil will be contained within a high-density polyethylene (HDPE) liner system. A 2’ berm will be constructed around the perimeter with imported clean aggregate material. All loose stones, sticks, roots, & other debris will be removed from the areas in order to prepare a bed for the liner. The first layer will be a 2” bed of well-sorted coarse sand covered by a geotextile fabric, followed by a 40 mil HDPE liner that will be covered by another layer of geotextile fabric with an additional 4” of well-graded coarse sand to allow rubber-tired heavy equipment transit within the lined cell.
The contaminated soils will then be placed over the sand layer. As the contaminated soil is being placed, a bottom layer of 2” slotted pipe will be installed on 10-foot centers to allow the soil gas to be vented from the pile. An upper layer of 4” perforated pipe will be installed on 10’ centers to allow air to enter the pile for venting. A low point sump & drain is included to allow water collected by the drainage system to be removed from the pile. A 20 mil HDPE cover will be placed over the pile to control air movement, prevent precipitation from entering the pile, & avoid erosion.
The excavation (a critical path activity) will be completed no later than 9 July 2011 as indicated above, but other non-critical path activities may extend beyond this date. The ex situ ventilated stockpile is scheduled to be completed by 7 July 2011 based on completing soil placement 2 days after completion of the excavation activities. Any schedule slippage on the completion of the excavation would consequently delay the completion of this stockpile. The latest likely date of the stockpile completion is 11 July 2011.
The SVE blower installation & ventilation blower installation at the stockpile is dependent on delivery of the equipment, which is tentatively anticipated to be received by 5 July 2011. Therefore, startup of the SVE & ventilation systems is anticipated to occur by 7 July 2011. Delays in the delivery of this equipment will consequently delay start-up of the systems, but will not delay construction activities or have an impact on critical path activities. |
Louis Howard |
| 7/21/2011 |
Document, Report, or Work plan Review - other |
Final F-22 Weapons Release Shop memorandum for ELM300 received and approved via email. The proposed actions to be taken at the F-22 Weapons Release Shop include the excavation of
contaminated soil, installation of a vapor barrier under the proposed site structure, and
installation of an SVE treatment system to remediate any remaining subsurface TCE and PCE
contamination. SVE systems are identified as the EPA's preferred remedy to address TCE and
PCE contaminated soil. |
Louis Howard |
| 3/7/2012 |
Update or Other Action |
Draft Technical Memorandum for the SVE installation & stockpile construction received.
This Technical Memorandum describes the field activities conducted during the 2011 non-time-critical removal action at the F-22 Weapons Release Shop (Building 17720). The selected EE/CA alternative, Minimal Excavation & In Situ Treatment (Alternative 6), utilizes SVE technology to address previously identified PCE, TCE, & DRO above ADEC Title 18 AAC 75 MTGW cleanup criteria while providing protection for construction workers at the proposed building footprint/SVE extraction system. Work was conducted in accordance with the 2011 SVE System Design & Construction WP Addendum.
Work Plan Deviations
Excavation of SVE trenches for header installation was completed concurrently with main soil excavation instead of first trenching to install the headers & then completing the removal of soil contaminated with PCE, TCE, & DRO. The deviation limited potential conflicts with SVE headers during soil excavation, prevented difficult access created by excavation equipment that created trenches running across the site, & allowed excavation equipment & dump trucks to operate on existing ground & pavement surfaces which prevented contamination of equipment tracks & wheels.
Operation of construction equipment on existing ground & pavement surfaces allowed removal of a tire wash station from the erosion control plan. Efforts to prevent soil from spilling onto areas outside the excavation included not filling the bucket to over flowing, shaking the bucket while over the excavation to settle the soil, & loading where the excavator could pivot to load the end-dump without moving the tracks.
SVE header piping extending from the west was sloped up to intersect with header piping extending from the south. This simplified header piping construction by requiring a single joint rather than the two joints as indicated in the WP Addendum. The 3-inch thick concrete cap specified to cover the SVE header trench was not placed between the proposed building footers connecting to Building 17720 in order to accommodate future construction activities in the site.
The SVE blower building was placed 36” from Building 17720 instead of 12” as shown in the WP Addendum. An electrical receptacle is present on the outside of Building 17720 where the SVE blower building was placed. JBER electrical guidelines require at least 36 inches of clearance for an electrical receptacle. Electrical connection of the SVE & stockpile blowers also required placement of additional equipment not included in the WP Addendum, including an electrical meter & shutoff switch.
The final dimensions of the ventilated stockpile were approximately 120 feet north to south & 89 feet east to west to fit field conditions & maintain access to the UAF research plot & a transformer. The perforated & slotted pipe headers were placed on 12-foot centers to accommodate the increase in stockpile length. The WP Addendum specified headers on 10-foot centers.
Implementation of EE/CA Alternative 6 included excavation of PCE-, TCE-, & DRO-contaminated soil from the site & installation of a SVE system. A ventilated stockpile was constructed to treat approximately 2,200 cy of PCE- & TCE-contaminated soil removed from the site using ex situ methods. Approximately 180 cy of DRO-contaminated soil was transported to ASR & underwent thermal treatment. The SVE system included approximately 503’ of down-hole hammer drilling to install 9 vacuum wells & 3 vapor monitoring point clusters. The SVE & ventilated stockpile systems are operational & will run for 2 years.
Sampling was performed at the site & ventilated stockpile areas to evaluate pre- & post-construction conditions, determine the potential for worker exposure, characterize waste soil & stockpile leachate, evaluate soil gas from existing soil vapor wells prior to construction, & to evaluate SVE system performance from soil vapor monitoring point clusters & SVE blower systems. Air monitoring was also performed during construction. Periodic soil gas sampling will monitor the effect of the SVE & ventilated stockpile systems on soil PCE & TCE concentrations & will be documented with quarterly reports.
Underground components of the SVE system were surveyed during construction & will be located by Jacobs before future construction activities begin at the site. After 2 years of operation, SVE headers, vacuum wells, & vapor monitoring points will be filled with grout, & abandoned in place, & aboveground components will be removed. The ventilated stockpile will be removed, post construction samples collected, & the area re-vegetated. Final disposal location of the ventilated stockpile soil after completion of remediation activities will be determined at a later time by the USAF.
|
Louis Howard |
| 12/7/2012 |
Update or Other Action |
F-22 Weapons Release Shop SVE Systems Report – Third & Fourth Quarters (21 February to 16 August 2012) received.
Summary & Recommendations
Screening Levels
ADEC issued its finalized its Vapor Intrusion Guidance for Contaminated Sites (ADEC 2012)
as this report was being written, & the proposed screening levels for shallow & deep soil were revised to reflect the new target levels contained therein. The revised screening levels proposed in this report are more relaxed for PCE but more stringent for TCE than those proposed in the first-quarter report (USAF 2012c). The revised proposed screening levels presented in Table 1 have been used throughout this report. TCE levels become the focus of system operations because they have commonly exceeded their screening level, whereas even the startup PCE levels did not exceed their screening level.
WRS SVE System
The WRS SVE system continued operation in its winter configuration from 21 February until 21 March, when it was reconfigured to focus extraction on those five wells (VW4, VW6, VW7, VW8, & VW9) with TCE exceeding the screening level. Three of the remaining wells were inactivated, & the fourth (VW3) supplied bleed air to prevent excessive vacuum. As the ground thawed during breakup, water rapidly accumulated in the knockout tank, overfilling it on 25 April. The system was shut down manually when the tank level switches failed to operate, & the next two weeks were spent troubleshooting & repairing the wiring related to the knockout tank.
Operation resumed on 11 May at reduced blower output, enabling operation of only the five wells of interest, & VW3 joined the inactive group. Operations continued with only minor interruptions for power outages through the end of the reporting period (16 August). Important developments were as follows:
-TCE in composite samples have remained steady at approximately twice the revised proposed screening level since late in the first quarter. However, TCE fell by approximately 50 percent in the two individual wells sampled during the reporting period, with the change occurring between the 10 February & 8 August sampling events. Only the three most southwesterly wells (VW6, VW7 & VW9) are thought to have exceeded the TCE screening level at the end of the fourth quarter. These three wells lie outside the footprint of the new F-22 Weapons Release Shop, & contamination there has little likelihood of affecting indoor air quality in the new building.
-Cumulative mass removal is estimated to have been 61 grams PCE & 960 grams TCE at the end of the fourth quarter, 65 percent of the total PCE & 60 percent of the total TCE that is projected to be removed over the 2-year operating period of the system.
-Measurements in the vacuum monitoring points continue to indicate less flushing than expected at the design radius of influence, which reduces the effectiveness of the system. Some compensation is achieved by operating the wells at 150 percent of their design flows (the maximum achievable while maintaining a reasonable manifold vacuum). Because the only wells thought to exceed the TCE screening level at the end of the fourth quarter lie outside the footprint of the new building, the treatment period will not need to be extended.
Contaminant concentrations have always met the revised proposed screening level of 1,800 µg/m3 for PCE, & the revised proposed screening level of 88 µg/m3 for TCE has been met since late in the first quarter for VW1, VW2, & VW3 beneath the footprint of the new building. Outside the footprint of the new building, TCE in VW9 fell by 42 percent between the end of the second quarter & the end of the fourth quarter from 1,000 µg/m3 to 580 µg/m3, but remains the most highly contaminated well. VW6 & VW7 also exceed or are near the TCE screening level, while VW4 (beneath the new building) & VW8 are probably below the screening level as of the end of the fourth quarter.
Extraction will continue to focus on the five wells with the highest remaining contaminant concentrations (VW4, VW6, VW7, VW8, & VW9) in order to maximize mass removal. The next report will cover the six-month period ending in February 2013. Because 2011-2012 winter conditions had little effect on subsurface vacuum distribution & well performance, no major changes in operations are planned for the upcoming winter.
System operations are planned to continue into August 2013. At that time, VW9 will probably still be producing air above the TCE screening level, but the other four active wells may have cleaned up. The WRS SVE system will have mitigated the threat of VI into the new F-22 Weapons Release Shop, & further operation would produce only very slow improvement at VW9. |
Louis Howard |
| 12/13/2012 |
Update or Other Action |
USEPA Region 10 Office of Environmental Assessment (OEA): OEA Recommendations regarding trichloroethylene toxicity in Human Health Risk Assessments. This memorandum supersedes previous communications from this office regarding the selection of toxicity values for trichloroethylene (TCE) in human health ri sk assessments, including a September 23, 2008 memorandum from me to Dan Opalski, then the director of the Office of Environmental Cleanup (ECL). We also have communicated our recommendations in recent years to each of the four states in Region 10, as we will do with these new recommendations.
Please share the information in this memorandum with your staff who are involved with the
investigation or cleanup of RCRA or CERCLA sites, where TCE is a common chemical of
concern.
We previously had a need to make recommendations regarding TCE toxicity because the re were
various available values from different sources, but none on the EPA Integrated Risk Information
System (IRIS), typically the preferred source of toxicity information for EPA. EPA's Office of
Research and Development (OR D) finalized its toxicological review of TCE in 2011, and IRIS
was updated in October of that year with values for chronic oral and inhalation exposures to
TCE. This office recommends that the values now avai lable on IRIS for chronic TCE exposures
be utilized for risk assessment purposes in Region 10. We would li ke to take this opportunity to point out that media concentrations of TCE that are based on chronic ex posures, noncancer
endpoints and a hazard quotient of I should be given special atte ntion, as the hazard quotient
may be exceeded at media concentrations that are calculated to represent individual excess
lifetime cancer risks of 1 E-4 and 1 E-5. The precise concentrations will depend upon the media
and the exposure scenarios of concern.
In order to calculate a health-protective TCE concentration for indoor air in a residential setting, the default Superfund chronic scenario assumes exposure of 24 hours per day, 350 days per year, which provides for a period of absence of two weeks per year. This yields a noncancer TCE concentration of 2.1 ug/m3 , representing a hazard quotient of 1.0. (The air TCE screening level concentration representing an individual excess lifetime cancer risk of I E-6 is 0.43
uglm3 for the default residential exposure scenario.) For short-term exposure concerns (i.e., to protect against fetal cardiac malformations) during any 21-day period of time in a given year, the exposure frequency should be adjusted to 365 days per year, resulting in a calculated concentration of 2.0 ug/m3
For calculation of a protective concentration of TCE in indoor air in a commercial/industrial
setting, the default Superfund chronic scenario assumes 8 hours/day, 5 days/week, 250 days per
year, which like the default residential calculation assumes an absence of two weeks during a
year. The chronic indoor air concentration representing a hazard quotient of 1.0 for this scenario is 8.8 ug/m3. (The air TCE screening level concentration representing an individual excess lifetime cancer risk of I E-6 is 3.0 ug/m3 for the default commercial/industrial exposure scenario.) For the short-term exposure concern, when women of reproductive age may be present at any time, the exposure frequency should be increased to 260 days per year to eliminate the assumption that there is a yearly two-week absence, since any given 21-day period is to be protective.
This results in an indoor air criterion of 8.4 ug/m3 representing a hazard quotient of 1.0. If the exposure time and frequency at a given commercial/industrial building is known to be other than the default Superfund assumption of 8 hrs/day, 5 days/week, 250 days/year, additional adjustments may be made in the calculation of building-specific, short-term exposure concentrations, just as they also may be made for the calculation of the building-specific chronic exposure concentrations.
To calculate short-term, noncancer TCE concentrations for other exposure media, Superfund
default exposure-related variables should be changed, where necessary, to include adult-only
values (e.g., exposure frequencies and durations, body weights, soil and other media ingestion
rates, and dermal surface areas exposed), with no assumed hiatus times (i.e., no assumed
vacations or other absences). |
Louis Howard |
| 1/4/2013 |
Update or Other Action |
USEPA OSWER Directive 9355.6-12 Sample Federal Facility Land Use Control ROD Checklist with Suggested Language (LUC Checklist).
While the checklist applies to LUCs, ROD reviews indicated a slight problem with the Declaration language which often states who selected the remedy. Where that language is included, please ensure that the federal agency & EPA select the remedy.
This checklist applies to all federal facility RODs. At Air Force facilities, numbers 1-8 & 10-19 should be included in the ROD as applicable (generally, numbers 18 & 19 apply at closing facilities, but they may have application elsewhere). For all other federal facility RODs (DOE, Navy, Army & others), the LUC implementation details are generally placed in a post-ROD enforceable document.
Therefore, numbers 1-9 below would usually appear in the ROD, while numbers 10-19 would be placed in a post-ROD enforceable document such as the LUC Remedial Design or Remedial Action Workplan. In some Regions, the term LUC Implementation Plan is used rather than LUC RD or RA Workplan. The specific post-ROD document where the LUC implementation details are designated may vary by site (for instance, it may be called a LUC Implementation Plan or LUCIP), as long as the specific document is identified in the ROD & is enforceable.
Air Force RODs should address numbers 1-8 & 10-19, below. All other federal facility RODs should address numbers 1-9, below & numbers 10-19 in the RD/RAWP. Where appropriate, Regions should consider including concepts & provisions in RODs, etc., similar to the samples provided below in order to ensure protective remedies:
_____1. Map/Figure showing boundaries of the land use controls
_____2. Document risk exposure assumptions & reasonably anticipated land uses, as well as
any known prohibited uses that might not be obvious based on the reasonably anticipated land
uses. (For example, where “unrestricted industrial” use is anticipated, list prohibited uses such as on-site company day-care centers, recreation areas, etc.)
_____3. Describe the risks necessitating the LUCs.
_____4. State the LUC performance objectives. We have had comments on these because several of the objectives have not been clear. The following are some examples of what we have been looking for:
1. Prevent access or use of the groundwater until cleanup levels are met.
2. Maintain the integrity of any current or future remedial or monitoring system such as monitoring wells, impermeable reactive barriers.
3. Maintain the 12-inch vegetative soil layer to limit ecological contact.
4. Prohibit the development & use of property for residential housing, elementary & secondary schools, childcare facilities & playgrounds.
_____5. Generally describe the LUC, the logic for its selection & any related deed restrictions/notifications. (See also #16, below)
_____6. Duration language: “Land Use Controls will be maintained until the concentration of hazardous substances in the soil & groundwater are at such levels to allow for unrestricted use & exposure."
_____7. Include language that the [federal agency] is responsible for implementing, maintaining, reporting on, & enforcing the LUCs. This may be modified to include another party should the site-specific circumstances warrant it.
_____8. Where someone else will or the federal agency plans that someone else will ultimately be implementing, maintaining, reporting on, & enforcing LUCs, the following language should be included:
“Although the [federal agency] may later transfer [has transferred] these procedural responsibilities to another party by contract, property transfer agreement, or through other means, the [federal agency] shall retain ultimate responsibility for remedy integrity.”
_____10. Commitment by federal agency to address any situation that may interfere with the effectiveness of LUC:
“Any activity that is inconsistent with the IC objectives or use restrictions, or any other action that may interfere with the effectiveness of the ICs will be addressed by the [federal agency] as soon as practicable, but in no case will the process be initiated later than___ days [10 days suggested] after the [federal agency] becomes aware of the breach.”
_____11. Commitment by federal agency to notify EPA of & address any situation that may interfere with the effectiveness of LUC:
“The [federal agency] will notify EPA & [the state] as soon a practicable but no longer than ten days after discovery of any activity that is inconsistent with the IC objectives or use restrictions, or any other action that may interfere with the effectiveness of the ICs The [federal agency] will notify EPA & [the state] regarding how the [federal agency] has addressed or will address the breach within 10 days of sending EPA & [the state] notification of the breach.” See directive for rest of text. |
Louis Howard |
| 6/28/2013 |
Update or Other Action |
Work Plan for the F22 Weapons Release Shop received.
The goal of this project is to conduct a remedial investigation (RI) and feasibility study (FS)
for Site SS109, F-22 Weapons Release Shop (Building 17720) to characterize environmental
conditions, define the nature and extent of contamination and estimate the risk to human
health and the environment quantitatively. The results of the investigation will be presented in
an RI/FS report. This Work Plan is the primary planning document; it has been prepared to
ensure that the project goals are met for the site.
This Work Plan has been drafted in accordance with U.S. Air Force (USAF), Occupational Safety and Health Administration (OSHA), and Alaska Department of Environmental Conservation (ADEC) guidance and regulations; the Department of Defense (DoD) Quality Systems Manual for Environmental Laboratories (QSM) version 4.2 (DoD 2010); the Uniform Federal Policy for Quality
Assurance Project Plans Manual (UFP-QAPP) (Intergovernmental Data Quality Task Force
2005, 2012); and Guidance for Conducting Remedial Investigations and Feasibility Studies
Under CERCLA (U.S. Environmental Protection Agency [EPA] 1988).
Up to five groundwater monitoring wells may be installed at the site in accordance with
ADEC standards. All monitoring wells will be advanced using a dualtube direct push drill rig. During drilling, an analytical soil sample will be collected every 5 feet using a 1.8-inch plastic core sleeve. The completed wells will be 2-inch diameter, schedule 40 polyvinyl chloride (PVC) stick-up wells with a minimum of three protective bollards per well. Once wells are developed and purged, a groundwater sample will be collected. Samples will be analyzed for DRO by AK102, GRO by AK101, and VOCs by SW8260.
Up to 15 soil borings may be advanced to a depth of 60 feet bgs using a dual-tube direct push
drill rig. An analytical soil sample will be collected every 5 feet using a 1.8-inch plastic sleeve and will be analyzed for DRO, GRO, and VOCs. Groundwater grab samples will be collected from each boring using temporary well points. A Teflon bailer will be used to collect each sample, which will be analyzed for DRO, GRO, and VOCs. Upon completion of sampling, the borings will be backfilled using bentonite or similar material to eliminate a preferential pathway for contamination. |
Louis Howard |
| 7/11/2013 |
Document, Report, or Work plan Review - other |
Staff provided comments on the RI/FS WP
5.2 Installation of GW Monitoring Wells
ADEC is requesting that 1,4-dioxane be sampled for in GW where TCE or 1,1,1- TCA contamination exists or was previously above cleanup levels at any site (CERCLA or State restoration or compliance). Please incorporate these comments into any basewide sampling plans (current/future).
AFCEE research has found 1,4-dioxane at AF sites contaminated with TCE. The study, titled "Co-Occurrence of 1,4-Dioxane with TCE in Chlorinated Solvent GW Plumes at US AF Installations: Fact or Fiction," found detections of 1,4-dioxane at sites with TCE, independent of TCA.
"Surprisingly, 64.4% of all 1,4-dioxane detections were associated with TCE independently," the researchers say in the abstract. "Given the extensive data set, these results conclusively demonstrate for the first time that 1,4-dioxane is a relatively common GW co-contaminant with TCE."
The study authors recommend site investigations consider 1,4-dioxane as a potential co-contaminant of TCE at GW plume sites. The study, which was published in the Integrated Environmental Assessment & Management journal last year, explicitly warns that new discoveries of 1,4-dioxane contamination could delay cleanup completions & require more costly revisions to existing remedies, noting that there is strong evidence suggesting that 1,4-dioxane "will migrate much further than chlorinated solvents."
ADEC has promulgated enforceable cleanup levels (not advisories) for 1,4-Dioxane in soil & GW (latest version 18 AAC 75 April 2012 Table B1 & Table C) effective since 2008 which has remained unchanged in the 2012 revised regulations.
Soil Under 40 inch Zone
540 mg/kg direct contact
0.21 mg/kg migration to GW
0.077 mg/L (77 µg/L) Table C GW cleanup level
1,4-Dioxane readily leaches to GW, is not expected to adsorb significantly to soil particles, & is difficult to biodegrade. Due to these properties, a 1,4-Dioxane plume typically proceeds ahead of the chlorinated solvent plume, & will tend to impact an aquifer system to a much larger extent.
Suggested lab methods: SW-846 Method 5030C, SW-846 Method 5021, SW-846 Method 8261A, SW-846 Method 5031, SW-846 8270C SIM, LVI & isotope dilution (1.0 µg/L or 2.0 µg/kg reporting limits). Dioxane can be detected using EPA 8260; however, its high water solubility causes relatively high reporting limits.
Routine organic extraction procedures like those traditionally used for EPA 8270 analyses produce low recoveries (approximately 50% or less). Whatever lab method is proposed for 1,4-Dioxane by JBER, the lab method must be able to detect at or below the ADEC promulgated GW cleanup level in Table C & migration to GW cleanup level in soil.
Be aware that with ADEC’s regulatory revisions in 2014, the level for 1,4-Dioxane (as well as many other compounds) will go down substantially from its current promulgated levels for soil & GW.
Finally, the EPA May 2013 RSLs for tapwater lists a lower screening level of 0.67 ug/L which equates to a 1x10-6 total risk as well as a noncarcinogenic screening level of 47 µg/L which equates to a HI of 0.1. Should 1-4 Dioxane be detected in the GW above the most stringent cleanup or screening level, then it will automatically be required to be analyzed for in the soil.
For each site contaminant, a risk-based screening level needs to be determined. The RBC for method two soil inhalation & direct contact pathways can be found in ADEC’s Cumulative Risk Guidance Appendix B for the applicable climate zone & correspond to the non carcinogenic risk (HQ) of 1 & carcinogenic risk level of 1 x 10-5.
These RBCs are calculated using the equations presented in DEC’s Cleanup Levels Guidance (June 9, 2008) & takes into account default exposure & soil/aquifer data as well as toxicological data specific to the compound of interest. For risk screening purposes, these levels should be adjusted to the non carcinogenic risk (HQ) of 0.1 & carcinogenic risk level of 1 x 10-6. If compounds that are not listed in the guidance are detected in soil or GW, screening levels can be obtained from the RSLs (latest version is May 2013) adjusted to a carcinogenic risk level of 1 x 10-6 & an HQ of 0.1. Initial screening for all sites should be against residential exposure scenarios. If no screening criteria can be obtained from the above noted sources, the compound should be retained for qualitative evaluation in the HHRA.
|
Louis Howard |
| 8/2/2013 |
Document, Report, or Work plan Review - other |
EPA provided comments on the draft RI/FS Work Plan.
The Draft F-22 Weapons Release Shop Remedial Investigation/Feasibility Study Work Plan (the Draft RI/FS WP) does not include many of the elements of RI/FS project plans, as outlined in Appendix B of the Environmental Protection Agency (EPA) Guidance for Conducting Remedial Investigations & Feasibility Studies Under CERCLA (the RI/FS Guidance), dated October 1988. In addition, the Draft RI/FS WP does not follow the Suggested RI/FS Work Plan Format displayed in Table 2-3 of the RI/FS Guidance. Please revise the Draft RI/FS WP to include the applicable elements RI/FS project plans, outlined in Appendix B of the RI/FS Guidance. In addition, please consider revising the Draft RI/FS WP to follow the Suggested RI/FS Work Plan Format displayed in Table 2-3 of the RI/FS Guidance
The Draft RI/FS does not include any reference to conducting a risk assessment either as a separate document or as a component of the RI. Please revise the document to include a risk assessment, & identify who will conduct the risk assessment.
The F22 WRS has operated a SVE system for volatile organics as a mitigation measure for construction worker exposure to soil gas vapors, & the conceptual site model as well as other areas in the document mention the complete pathway for current & future site visitor & indoor worker exposure via inhalation. The RI/FS must be revised to include assessment of vapor intrusion to the nearby buildings. Please describe the method (sampling, modeling,) that will be used to assess volatile organic concentrations in air. If sampling will be used to assess volatile organic concentrations in air, revise all pertinent sections of the draft RI/FS to include this media.
The Draft RI/FS WP does not include a GW elevation contour map to support the statement that GW flow is to the southwest. Please revise the Draft RI/FS WP to include a figure displaying GW contour data.
EPA R10 requires the use of SW 5035/8260 low level analysis for soil media on CERCLA sites. Recent guidance suggests interference from sodium bisulfate; the preferred matrix is soil samples in VOA vials with water carrier. Please revise all worksheets where SW8260-Medium methods will be used in soils to include SW8260 low level soil sampling & analysis.
The Draft RI/FS WP does not present a sufficiently detailed rationale for number, type, location, & depth of the proposed soil & GW samples. For example, the Draft RI/FS WP does not discuss the rationale for the selection of the five soil boring locations that will be converted into monitoring wells, & why 15 GW grab samples & five GW samples are sufficient to characterize the horizontal extent of contaminants in site GW. Please revise the Draft RI/FS WP to provide a detailed discussion of the rationale for the number, type, location, & depth of the proposed soil & GW samples.
According to the second full paragraph on page Overview-6, “TCE [trichloroethene], PCE [tetrachloroethene], methylene chloride, benzo(a)pyrene, & DRO [diesel range organics]” were the analytes that exceeded cleanup levels during the February 2010 investigation; however, the next paragraph indicates that samples collected during the July 2010 were analyzed for VOCs, DRO, GRO, & residual range organics (RRO). It is unclear why samples collected during the July 2010 investigation were not also analyzed for semivolatile organic compounds (SVOCs) since benzo(a)pyrene exceeded cleanup levels in February 2010. Please revise the text to explain why SVOCs were not included among the analyses conducted during the July 2010 investigation.
|
Louis Howard |
| 9/17/2013 |
Document, Report, or Work plan Review - other |
ADEC has reviewed JBER's responses to ADEC's comments on the Draft F22 Weapons Release Shop RI/FS Work Plan received via email on September 17, 2013. The responses to ADEC's comments are acceptable and the document may be finalized after EPA has reviewed and accepted the responses to its comments on the document. |
Louis Howard |
| 9/17/2013 |
Update or Other Action |
JBER-Elmendorf accepts comments on 1,4-Dioxane sampling.
Applicable sections and QAPP worksheet in the Work Plan will be revised to include 1,4-dioxane analysis for all groundwater and soil samples collected during the investigation. The method used to evaluate the material will be added to the Work Plan. |
Louis Howard |
| 12/30/2013 |
Document, Report, or Work plan Review - other |
EPA review comments to JBER RTC on EPA comments for the WP.
It appears only section 5.4 will be modified to include references to soil gas or VI sampling. Four gas probes around two buildings, with only one sample event, does not capture spatial or temporal variability of the potential vapor intrusion pathway. The F22 WRS & Hangar 15 combined cover an area exceeding 7 acres; there is known TCE soil contamination on nearly one acre of this area around the F22 WRS. Indoor air samples are preferred to estimate the exposure risk at the F22 WRS & may also be considered at Hangar 15.
Please display monitoring well IS6-01 on the Figures in the report. (p. 16 of the 2013 JBER Env. Program atlas has Bldg 17720 & IS6-01 on page 16 to show the relationship.
This issue will come up again in other comments. Criteria need to be established prior to the fieldwork to determine what constitutes a good location for a sample, monitoring well. Etc…
Define what is meant by the ‘previous’ waste characterization & how those results will inform current sampling. The SOP for TCLP was not found in App. C
Use of the phrase ‘environmental impacts’ seems out of place. Suggestion to use the word ‘contaminants’
From the EPA Environmental Assessment Sourcebook, 1996, edited by J. Russell Boulding, page 305.
“For most compounds, including VOCs, positive displacement devices allow collection of accurate & precise samples, with concentrations of VOCs typically within 10% of true concentrations. Some grab samplers, particularly bailers, may also produce representative samples but their effectiveness is highly dependent on mode of operation & the constituents of interest. Under unfavorable field conditions or when operated improperly, bailers may produce errors in VOC concentrations from -10% to -80% or more.”
The criteria that would determine relocation of a well must be provided in the workplan prior to commencing field work.
Please add the text described in the response to section 5.2 of the workplan.
The text in General Comments #10 does not describe waste characterization or storage. Please describe how IDW will be stored & characterized.
EPA will provide approval in the form of a memo after review of the redline draft final workplan. The role of subcontractors must be included in the worksheet
The referenced worksheet #10 was not attached to the email with the RTC. Please provide the attached worksheet for review.
The sampling locations & number of monitoring points (boreholes & monitoring wells) are insufficient to adequately characterize potential releases from Hangar 15 floor drains. Please describe why only the outdoor inhalation pathway will be investigated. Please put monitoring well IS6-01 on figures as applicable. Please define the ADEC target levels for subslab soil gas & indoor air samples.
Predetermined contract quantities are not a basis for remedial investigations. The criteria that would determine relocation of a well must be provided in the workplan prior to commencing field work.
Add the 2011 removal action area to the appropriate figures. Four gas probes around two buildings, with only one sample event, does not capture spatial or temporal variability of the potential vapor intrusion pathway. The F22 WRS & Hangar 15 combined cover an area exceeding 7 acres; there is known TCE soil contamination on nearly one acre of this area around the F22 WRS. Indoor air samples are preferred to estimate the exposure risk at the F22 WRS & may also be considered at Hangar 15.
Please describe the depth at which GW samples will be taken. The criteria that would determine relocation of a well must be provided in the workplan prior to commencing field work.
Inconsistent with the response for comment #37, which mentions a new figure A-9 to display locations of the 2010 sampling event.
|
Louis Howard |
| 4/9/2014 |
Document, Report, or Work plan Review - other |
ADEC RTCs for Soil Gas Sampling Work Plan Addendum ADEC specific comments
Issue: introduction text did not incorporate any of the recommended changes in the RTC to the SOP-5c (section 1.0? or elsewhere).
Comment #1 WESTON has added text to the soil gas SOP INTRODUCTION to address the comment. The text insert (on page 3) says “If the site-specific criteria in the June 28, 2013 ADEC-USAF-Weston meeting minutes are met, indicating vapor intrusion potential, and the site has non-hydrocarbon contaminants which do not biodegrade under aerobic conditions (for example a waste oil site with chlorinated compounds), then soil gas samples will be collected regardless of the soil oxygen concentration.”
We also think that the June 28, 2013 ADEC-USAF-Weston meeting minutes addresses this issue, as follows:
3.2 The VI pathway will be considered potentially complete if non-hydrocarbon VOC contamination above 18 AAC 75 Table B1 and C levels is present within 100 feet (vertically or horizontally) of the foundation of a currently occupied or occupiable building.
3.3 If the VI pathway is potentially complete, soil gas samples will be collected and analyzed by TO15. The TO15 analyte list with non-hydrocarbon contaminants includes the full list in Appendix E in the ADEC VI Guidance. The resulting contaminant concentrations in soil gas will be compared to screening levels listed in the ADEC VI guidance and/or used as input to the Hydrocarbon Risk Calculator (HRC).
Comment #2WESTON has added text to the soil gas SOP INTRODUCTION to address the comment (page 4). The text insert says “In general, TO-15 analysis run on 1 liter SUMMATM canisters will be the default laboratory method…..”.
Note that the table embedded in the text of the soil gas SOP which describes the analytical methods indicates that the TO-15 analysis will use 1 liter SUMMATM canisters as the collection device, and that the TO-17 analysis will use sorbent tubes as the collection device.
All other RTCs are acceptable to ADEC with the exception of the introduction text additions for comment 1 and 2 that did not make it to the SOP.....
|
Louis Howard |
| 6/12/2014 |
Enforcement Agreement or Order |
Federal Facility Agreement (FFA) Document Schedule for SS109- F22 Weapons Release Shop, JBER-Elmendorf.
Attached for your review and acceptance is the proposed document schedule for SS 109 - F22 Weapons Release Shop on Joint Base Elmendorf-Richardson, Elmendorf (JBERE), Alaska. If approved, the schedule will be attached to the current JBER-E FF A (15 November
1991).
If you concur with the proposed schedule, please sign in the block provided on the attached signature page and return the original signature page to me. Should you have questions or comments, please feel free to contact me at (907) 384-1824.
Document type: Primary, Draft Remedial Investigation/Feasibility Study, date due for agency review 15 September 2015
Document type: Primary, Draft Record of Decision, date due for agency review 15 February 2017
Upon approval, this document will be attached to the current FFA (15 November 1991). The
document schedule may be updated or modified to include additional primary or secondary
documents as necessary to meet FF A requirements. Changes will require approval of FF A
Project Managers.
Signed by G. Fink USAF, S. Halstead EPA, L. Howard ADEC.
|
Louis Howard |
| 7/10/2014 |
Update or Other Action |
Draft F-22 Weapons Release Shop SVE report received for review and comment.
This After-Action Report provides details of the final two quarters of field activities and
summarizes all activities performed during the two years of operations and maintenance (O&M) of the two soil vapor extraction (SVE) systems constructed as part of the non-time critical removal action at the F-22 Weapons Release Shop (WRS) area of Joint Base Elmendorf-Richardson (JBER).
In 2010, subsurface chlorinated solvent contamination was discovered below and adjacent to
the footprint of the planned expansion of Building 17720, located in the F-22 WRS area. The
2011 Engineering Evaluation and Cost Analysis documented field investigations of the nature and extent of contamination and evaluated several remedial alternatives. Alternative 6 (“Minimal Excavation and In situ Treatment”) was implemented in July and August 2011 to enable construction to proceed on schedule. Remedial actions included excavation of 2,200 cubic yards of tetrachloroethene (PCE)- and trichloroethene (TCE)-contaminated surface and subsurface soils from the areas of the future building footings, installation of the WRS SVE system to treat the remaining TCE and PCE contamination in situ, and construction of a VSP that utilized SVE to treat the excavated soil.
The WRS and VSP SVE systems were designed to remediate contaminated soil within two years of operation. These systems operated from 19 August 2011 to 01 August 2013. At the WRS, PCE and TCE vapor concentrations in eight of nine vacuum wells were below their project action levels for vapor intrusion from deep soil by the end of operations. For the WRS, project action levels were set at one-tenth of the ADEC vapor intrusion guidance level for deep soil. In VW9, located outside the Building 17720 expansion footprint, TCE remained in excess of its action level.
Eighteen days after the end of operations, the five most contaminated wells were resampled to evaluate rebound. Although TCE in each well
exceeded the project action level (88 µg/m3), it remained less than the ADEC guidance level
for deep soil (880 µg/m3). Therefore, the WRS SVE system met its primary objective of
mitigating the threat of intrusion of PCE or TCE vapor into the Building 17720 expansion.
At the VSP after of two years of operations, TCE and PCE concentrations in extracted air
were below their project action levels for vapor intrusion from shallow soil.
For the VSP, project action levels were set at one-tenth of the ADEC vapor intrusion guidance level for shallow soil. Concentrations of PCE had been below its project action level (180 µg/m3) since system operation began. However, confirmation soil samples collected from seven locations
during the eighth quarter failed to meet the most stringent (migration to groundwater) soil
cleanup levels for PCE (one location) and TCE (six locations). Therefore, the VSP did not
meet its primary objective of reducing contaminant concentrations to levels that would permit
re-use of the excavated soil. Further treatment or permanent disposal of the soil is required. |
Louis Howard |
| 7/30/2014 |
Document, Report, or Work plan Review - other |
Staff commented on the after-action report.
6.0 Summary
Page 6-2
The vacuum extraction wells may have treated the soil so that no vapor intrusion above risk levels from TCE/PCE into Building 17720 expansion area, but the nature and extent of soil and groundwater contaminated with chlorinated solvents has yet to be conducted in accordance with the Elmendorf Federal Facility Agreement under CERCLA. It is anticipated a permanent remedy or remedial action will be taken at this source area as required by the 1991 Federal Facility Agreement. This effort was to evaluate the SVE treatment system and is not a remedial investigation as required by the Federal Facility Agreement for releases of CERCLA hazardous substances, pollutants or contaminants.
A remedial action is defined in 40 CFR 300.5 and shall mean those actions consistent with permanent remedy taken instead of, or in addition to, a removal action in the event of a release or threatened release of a hazardous substance into the environment, to prevent or minimize the release of hazardous substances so that they do not migrate to cause substantial danger to present or future public health or welfare or the environment (II. Definitions, 1991 Elmendorf Federal Facility Agreement).
Page 6-3
The text states: “With ADEC approval, the soil could be treated using thermal desorption. Otherwise, the soil could be shipped to a properly licensed landfill (e.g., the Columbia Ridge Landfill in Arlington, Oregon).”
Both EPA and ADEC would have to approve any soil treatment/disposal and ADEC is unaware of any Alaska company that could thermally desorb chlorinated solvent contaminated soils that is EPA approved as an Off-Site facility in accordance with the Off-Site rule (40 CFR 300.440).
Table E-1 Field and Laboratory Quality Control Sample Quantities
Soil Analytical Method
SW8260 C
Please be aware that EPA prefers “low-level” analysis for VOCs in soil using a VOC/VOA vials with a water carrier in addition to any ADEC methanol preserved VOC soil sampling requirements (Appendix C: General CLP Sample Collection Guidelines VOAs in Water EPA 540-R-09-03 January 2011). Sodium bisulfate preservation may be used for “low-level” analyses, however the laboratory must have data validation which shows that no loss of VOCs were encountered during the use of sodium bisulfite preservative (e.g. interference with foaming).
|
Louis Howard |
| 8/20/2014 |
Document, Report, or Work plan Review - other |
Responses to ADEC's comments on the Draft WRS SVE After Action Report are acceptable to ADEC. Finalize the document. |
Louis Howard |
| 1/12/2015 |
Document, Report, or Work plan Review - other |
Staff provided comments on the Air Force's response to comments. RTCs to ADEC's previous comments are acceptable.
5.4 Soil Gas Sampling
Recommend that three soil gas probes be installed per building as recommended by ADEC’s 2012 Vapor Intrusion Guidance document. Additionally, locations of soil gas points should also be based on building survey (Appendix I of ADEC 2012 VI Guidance) results.
SOP JE-SOP-5002 Soil Gas Sample Collection
NOTE-The following comments apply to all contractors for JBER-E and JBER-R sites where soil gas sampling is proposed (i.e. PBR-WESTON SOLUTIONS/CH2MHill) in addition to this site:
1. Please note: Soil gas probe tubing should be constructed of nylon, stainless, steel, or Teflon. Polyethylene tubing is not recommended.
2. Helium tank should be research grade and 99.99% percent pure helium. Recommend the text be revised to reflect this.
3. Recommend that barometric pressure, and temperature be recorded in a field notebook during the days of probe installation and sampling.
4. Please note that all field measurements, maintenance and calibration records must be recorded in a field notebook or a signed field form. Helium detector shall be calibrated on a daily basis. |
Louis Howard |
| 4/9/2015 |
Document, Report, or Work plan Review - other |
The Alaska Department of Environmental Conservation has received the final version of the document on April 8, 2015. ADEC has no further comments on the document and will approve the final version as submitted. |
Louis Howard |
| 2/3/2016 |
Update or Other Action |
Staff commented on the revised draft work plan for the RI/FS at this site. Main comments were to update the outdated references to the DOD QSM 5.0 (July 2013), EPA RSLs (November 2015), ADEC CS regulations and risk assessment procedure manual as well as the UST procedure manual. Staff also noted that the work plan referenced expiring lab approval and accreditations which will need to be documented in a work plan addendum with the renewed approvals and accreditations.
See site file for additional information. |
Louis Howard |
| 3/17/2016 |
Document, Report, or Work plan Review - other |
EPA comments on the HHRA App. G of the RI/FS workplan previously submitted w/o an HHRA component.
COPC LODs: Please clarify the basis (or preferred basis, where multiple exist) of the level of detection (LOD). Use of a sample quantitation limit (SQL)-based reporting limit (or LOD) is preferred over other possible choices such as the method detection limit.
It is unclear if potential impacts to a future construction worker as a function of exposure to vapors during trenching conditions (i.e., inhalation of off-gassing volatile organic compounds from soil under semi-confined exposure conditions) will be considered in the forthcoming HHRA. If volatile organic constituents are detected in subsoils, please consider evaluating construction worker inhalation exposure under trench air conditions (de facto/partial confined space exposure. If this pathway will not be evaluated, provide sufficient justification for its exclusion. In addition, add this pathway to the graphical CSM, if applicable.
addition, add this pathway to the graphical CSM, if applicable
Appendix G does not discuss how exposure point concentrations (EPCs) will be calculated for residents. Please ensure that two separate EPCs are developed to address future potential residential exposure to soil. One EPC should be based on surface soil data-only (representing the predominant basis for exposure) and a second EPC should be developed based on surface soil and subsurface soil data combined. This latter EPC will form the basis for exposure as a result of site redevelopment and regrading, where these soil horizons are mixed, or where future residential activities (e.g., home maintenance or gardening) may allow for subsurface soil exposure. Risk and hazard estimates based on this set of EPCs should be presented to support defensible risk management decision making.
The human health ILCR risk should be run at 10-6 (the point of departure), and the risk assessment summary should report anything above 10-6. Moving to 10-4 can be done for determining cleanup levels and RAOs, but it must have rationale and consideration in the 5 balancing criteria.
The conceptual site model (CSM) is presented in Appendix A of the SS109 Remedial Investigation/Feasibility Study Work Plan; however, the graphical representation of the CSM should be included within the HHRA Work Plan (Appendix G) to represent a stand-alone document. Please revise Appendix G to include the CSM. |
Louis Howard |
| 3/22/2016 |
Document, Report, or Work plan Review - other |
Staff provided comments on the HHERA work plan. Main comments were regarding updating the risk assessment procedure manual referenced, use of EPA RSLs which are updated more frequently than the ADEC tables in 18 AAC 75 per the 2015 risk assessment procedure manual, finally, comments were made regarding the proper use of soil ingestion rates and body weight for exposure recommendations from the EPA Exposure Factor Handbook (2011).
See site file for additional information. |
Louis Howard |
| 4/20/2016 |
Update or Other Action |
ADEC, AFCEC & EPA signed a revision to the FFA Document Schedule.
See site file for additional information. |
Louis Howard |
| 6/12/2016 |
Update or Other Action |
ADEC, AFCEC, EPA signed a revision to the document schedule for the FFA.
See site file for additional information. |
Louis Howard |
| 11/30/2017 |
Update or Other Action |
Draft Remedial Investigation Report received for review & comment. COPCs at SS109 exceed PSLs in surface soil, subsurface soil, groundwater, & soil gas. Fuels, solvents & other VOCs, PAHs, & metals may contribute to residual human health risk, although metals exceedances are likely representative of naturally occurring concentrations. In 2016, soil samples exceeded the ADEC (most stringent) migration to groundwater cleanup levels (ADEC 2017c) for DRO, TCE, & naphthalene.
An SVE system formerly operated in the footprint of the Building 17722 reduced the concentrations of PCE & TCE in soil gas, but did not bring TCE to below PSLs or cleanup levels. While a vapor barrier protects indoor workers from VI risk in the newly constructed facility, 2016 exceedances show that soil gas contains unacceptable levels of TCE outside the former treatment area, & several other occupied facilities are located nearby. None of the concentrations approach the JBER soil gas thresholds for TCE of 2,100 µg/m3 (residential) & 8,800 µg/m3 (industrial) for ADEC notification. However, all 2010 & 2016 results that exceeded the TCE PSL (7 µg/m3, the VISL [EPA 2015] for a residential scenario) also exceed the VISL under a commercial scenario (29 µg/m3).
See site file for additional information. |
Louis Howard |
| 2/23/2018 |
Document, Report, or Work plan Review - other |
Comments provided on the Remedial Investigation human health risk assessment Report.
Main comments were that the cumulative non-cancer and cancer risk could be underestimated for groundwater since analysis for perfluorchemicals was not included in the data set for the risk assessment. Soil boring SB12 did have DRO in soil at 55’ bgs (1,600 mg/kg ) and DRO in groundwater at 24 mg/L. ADEC requests AFCEC provide clarification on how DRO contamination will be addressed near Building 16716 based on the information provided in this RI.
If there is no TCE contamination associated with SB12, then ADEC will assume SB12 is purely fuel contamination associated with the heating fuel UST at Building 16716. Based on the information presented in the RI, assuming the soil TCE result attributed to SB12 is in error, ADEC will withdraw its cleanup complete designation for Hazard ID 4086 which will designate it as an “ACTIVE” site and further request AFCEC validate the site, request additional funding to conduct additional investigation and/or remediation to address the fuel contamination currently excluded from CERCLA.
See site file for additional information. |
Louis Howard |
| 7/3/2018 |
Update or Other Action |
Milestone Federal Facility Agreement updates: Draft Feasibility Study report September 5, 2019, Draft Proposed Plan December 15, 2020 and Draft Record of Decision September 14, 2021. Signed by EPA, Air Force and ADEC remedial project managers on July 3, 2018. |
Louis Howard |
| 2/4/2019 |
Document, Report, or Work plan Review - other |
Staff provided comments on the draft feasibility study for SS109. Main comments were to create another alternative (#4) which combines alternatives 2 and 3 to satisfy the remedial action objectives instead of selecting two alternatives 2 and 3. Additionally, comments were made to include the uniform environmental covenants act (UECA) with the list of potential ARARs.
See site file for additional information. |
Louis Howard |
| 4/2/2021 |
CERCLA Proposed Plan |
DEC reviewed the draft "Proposed Plan for SS109 – F-22 Weapons Release Shop, Joint Base Elmendorf-Richardson, Alaska" and provided comments to the U.S. Air Force. The document describes the U.S. Air Force’s proposed plan to address contamination in soil excavated from SS109 on Joint Base Elmendorf-Richardson using soil vapor extraction, and protect receptors at the site from potential vapor intrusion into buildings using monitoring and land use controls. |
Melinda Brunner |
| 5/18/2021 |
Document, Report, or Work plan Review - other |
Reviewed the US Air Force's response to ADEC's comments (RTCs) on the Proposed Plan for SS109 – F-22 Weapons Release Shop, Joint Base Elmendorf-Richardson, Alaska. DEC Approved of the RTCs and requested a final Proposed Plan for approval. |
William Schmaltz |
| 5/28/2021 |
Document, Report, or Work plan Review - other |
DEC Approved of Final LTM and LUC Inspection Work Plan for select CERCLA sites dated May 2021. |
William Schmaltz |
| 8/9/2021 |
Document, Report, or Work plan Review - other |
DEC staff reviewed and provided comments on Draft 2020 Land Use Control report for Select CERCLA sites dated June 2021. Report summarized LUC inspections performed in December 2020. Most sites were covered in snow and a full inspection could not be performed until spring 2021. DEC requested that the spring 2021 inspections are included in the 2020 report or as a separate cover because they are a continuation of the 2020 inspections and separate of the 2021 inspections. |
William Schmaltz |
| 6/15/2022 |
Update or Other Action |
DEC reviewed and provided comments on SS109 Record of Decision. The ROD is specific to the soil stockpiles at the site. DEC requested that language in the ROD is modified to indicated this in an interim ROD specific to the stockpiles. |
William Schmaltz |
| 6/15/2022 |
Document, Report, or Work plan Review - other |
DEC provided comments on soil stockpile SVE system work plan. |
William Schmaltz |
| 1/19/2023 |
CERCLA ROD Periodic Review |
DEC reviewed the Draft Record of Decision and provided comments to USAF. |
William Schmaltz |
| 4/20/2023 |
Document, Report, or Work plan Review - other |
DEC reviewed and provided comments for the 2021 Annual Remedial Action-Operations and Long-Term Management Report for Select CERCLA Sites, Draft, dated December 2023. The report describes the site inspections, maintenance activities, and groundwater monitoring, at multiple sites located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Site inspections and sampling were recommended to continue for all applicable sites to ensure that conditions remain protective of human health and the environment. |
Ginna Quesada |
| 9/21/2023 |
Document, Report, or Work plan Review - other |
DEC approved the Final SS109 – F-22 Weapons Release Shop Record of Decision (ROD), dated August 2023. |
Ginna Quesada |
| 7/2/2024 |
Document, Report, or Work plan Review - other |
DEC approved the 2022 Annual Remedial Action-Operations and Long-Term Management Report for Select CERCLA Sites, Final, dated June 2024. The report describes the site inspections, maintenance activities, and groundwater monitoring, at multiple sites located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Site inspections and sampling were recommended to continue for all applicable sites to ensure that conditions remain protective of human health and the environment. |
Ginna Quesada |
| 8/20/2024 |
Document, Report, or Work plan Review - other |
DEC reviewed the SS109 Ventilated Stockpile Soil Vapor Extraction System Operations, Maintenance, And Sampling 2023 Summary Report Draft, dated August 2024. The report describes the soil sampling activities at the SS109 Ventilated Stockpile located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Trichloroethylene in soil continues to exceed DEC’s Migration to Groundwater Cleanup Levels suggesting that it may take at least another 10 years to reach the remediation goal. The report recommended the continued operation of the soil vapor extraction system along with multiple potential improvements to the operation to accelerate the remediation of soil. |
Ginna Quesada |
| 10/25/2024 |
Document, Report, or Work plan Review - other |
DEC approved the SS109 Ventilated Stockpile Soil Vapor Extraction System Operations, Maintenance, And Sampling 2023 Summary Report Final, dated October 2024. The report describes the soil sampling activities at the SS109 Ventilated Stockpile located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Trichloroethylene in soil continues to exceed DEC’s Migration to Groundwater Cleanup Levels suggesting that it may take at least another 10 years to reach the remediation goal. The report recommended the continued operation of the soil vapor extraction system along with multiple potential improvements to the operation to accelerate the remediation of soil. |
Ginna Quesada |
