to 15 or not to 15
Download
Skip this Video
Download Presentation
TO-15 or not TO-15?

Loading in 2 Seconds...

play fullscreen
1 / 23

TO-15 or not TO-15? - PowerPoint PPT Presentation


  • 196 Views
  • Uploaded on

TO-15 or not TO-15?. That is the question. James Picker, Ph.D. Objective. Compare/Contrast EPA Method 8260B vs. EPA Method TO-15/TO-14A. Used for the analysis of VOCs in soil vapor (gas) to measure health risk. Perceived (advertised?) Difference. OR. Actual difference. OR.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'TO-15 or not TO-15?' - miracle


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
to 15 or not to 15

TO-15 or not TO-15?

That is the question.

James Picker, Ph.D.

H&P Mobile GeoChemistry Escondido, CA

objective
Objective

Compare/Contrast

EPA Method 8260B vs. EPA Method TO-15/TO-14A

Used for the analysis of VOCs in soil vapor (gas) to measure health risk

H&P Mobile GeoChemistry Escondido, CA

slide3
Perceived (advertised?) Difference

OR

H&P Mobile GeoChemistry Escondido, CA

slide4
Actual difference

OR

H&P Mobile GeoChemistry Escondido, CA

summary epa 8260 vs to 15 14a
Summary EPA 8260 vs. TO-15/14A

Data Reduction

GC/MS System

Sample Preparation

SAME

IDENTICAL

SLIGHTLY DIFFERENT

H&P Mobile GeoChemistry Escondido, CA

similarities
Similarities

GC/MS Method (SCAN or SIM)

  • GC with FSCC (20-60m X 0.18-0.32mm id)
  • LRMS (quadrupole, ion trap, TOF)
  • *Concentration of compounds on multiadsorbent trap*
  • Uses Internal Standards/Surrogate(s) for accuracy/QC
  • Multipoint Calibration ICAL, linearity checks, Daily CCV
  • Varying sample size permitted
  • Quant by RFs

H&P Mobile GeoChemistry Escondido, CA

differences
Differences

EPA 8260B (modified)

*Standards in liquid (MeOH)*

Purge and trap

Purged from headspace and H2O using He or dry purging

Water management

Desorption direct to GC/MS

EPA TO-15/14A

*Standards in Air (N2)*

Vacuum (or Pressure) flow and Trap

pulled from cylinder, using pump or pressure

Desorption to cryofocus or directly to GC/MS.

Standards and Sample Preparation

H&P Mobile GeoChemistry Escondido, CA

standards in water or air
Standards in Water or Air

-

H&P Mobile GeoChemistry Escondido, CA

compounds analyzed equally well by epa 8260 or to 15
Compounds Analyzed equally well by EPA 8260 or TO-15
  • BTEX, Trimethylbenzenes, Freons
  • PCE, TCE, vinyl chloride, DCEs, 1,2- DCPE, 1,1,1,2- TCA
  • 1,1,1-TCA,

H&P Mobile GeoChemistry Escondido, CA

compounds analyzed with a slight high bias by epa 8260 versus to 15
Compounds Analyzed with a slight high bias by EPA 8260 versus TO-15
  • MTBE, other oxygenates
  • 1,1,2,2-TCA, 1,2- DCA, 1,1,2-TCA
  • Naphthalene
  • rest of common 8260 list

H&P Mobile GeoChemistry Escondido, CA

compounds analyzed with a high bias by epa 8260 versus to 15
Compounds Analyzed with a high bias by EPA 8260 versus TO-15

Ethanol, TBA

1,4 Dioxane

Acetone & other ketones

Any water soluble low volatility compound

H&P Mobile GeoChemistry Escondido, CA

differences ii
Differences II

Calibration and Range

EPA 8260B (modified)

“Typical” Calibration 500 – 50000 ug/m3 (160-16000 ppbv for benzene)

MDLs 100 ug/m3 (31 ppbv benzene)

For 8260 SIM 10 ug/m3 (3 ppbv benzene

EPA TO-15/14A

“Typical” Calibration 3-120 ug/m3 benzene (1-40 ppbv)

MDLs 0.3 ug/m3 benzene(0.1ppbv)

For TO-15 SIM 0.03 ug/m3 benzene (0.01ppbv)

H&P Mobile GeoChemistry Escondido, CA

calibration range mdl to highest standard assumes 20 cc sample
Calibration RangeMDL to highest standardassumes 20 cc sample

Normal Range

8260 SCAN

Extended by dilution

8260 SIM

TO-15/14A SCAN

TO-15/14A SIM

10-2 10-1 1 10 102 103 104 105

ug/m3

H&P Mobile GeoChemistry Escondido, CA

fail levels tce @ subslab tce @ 5 bgs
Fail LevelsTCE @ subslab TCE @ 5’bgs

EPA R9

CA-EPA

8260 SCAN

8260 SIM

TO-15/14A SCAN

TO-15/14A SIM

10-2 10-1 1 10 102 103 104 105

ug/m3

H&P Mobile GeoChemistry Escondido, CA

fail levels benzene @ subslab benzene @ 5 bgs
Fail LevelsBenzene @ subslab Benzene @ 5’bgs

CA EPA

EPA R9

8260 SCAN

8260 SIM

TO-15/14A SCAN

TO-15/14A SIM

10-2 10-1 1 10 102 103 104 105

ug/m3

H&P Mobile GeoChemistry Escondido, CA

project bl 4feb05 results in ug l
Project BL 4FEB05results in ug/L

Average % Diff across all compounds = 38%

H&P Mobile GeoChemistry Escondido, CA

project mc 1feb05 results in ppbv
Project MC 1FEB05results in ppbv

H&P Mobile GeoChemistry Escondido, CA

conclusions
Conclusions
  • For most vapor intrusion compounds of interest, methods yield identical results
  • For more water soluble compounds 8260 is within factor of 2. Fine for VI calculations
  • A few compounds may require TO method. Some compounds may require 8260 method
  • On-site analysis assists in decision making, regulatory QA requirements and assurance of tracer compound integrity

H&P Mobile GeoChemistry Escondido, CA

recommendations
Recommendations
  • Choose either or a combination of methods, depending on compounds and DLs required
  • Select on-site analysis for decision making, regulatory QA requirements (assurance of tracer compound integrity, purge volume testing, etc.)
  • Do onsite TO-15 where levels are low
  • Do onsite 8260 where levels are moderate to high
  • Follow with offsite TO-15 for Quality Assurance

H&P Mobile GeoChemistry Escondido, CA

slide22
H&P’s Solutions

Option 1 – Where 8260B Meets Project DQOs:

On-site, full QC 8260B fulfilling DTSC/LA-RWQCB requirements with off-site TO-15 confirmation on a sub-set of samples.

Option 2 – Where TO-14/15 is required to meet Project DQOs:

On-site screening-level 8260B of all samples with of-site analysis of ALL samples by TO-15.

Option 3 – For larger projects with lower DLs:

On site TO-15

  • All Options:
  • Fulfill all DTSC soil gas advisory requirements
  • Allow on-site analysis for leak/tracer compound test
  • Guarantee sample integrity
  • Provide real-time data for real-time decisions
slide23
James Picker, Ph.D.148 Vinewood Street

Escondido, CA 92029

(800) 834-9888www.HandPmg.com

ad