RE_ Tie s Dry Cleaning (ECSI 6478) Update

From: PUGH Mark * DEQ

Sent: Thu Mar 14 13:29:38 2024

To: Andrew Blake

Cc: Tera Heintz; NELSON Heidi * DEQ; kumkang793; Lance Downs; Greg Brown

Subject: RE: Tie's Dry Cleaning (ECSI 6478) Update

Importance: Normal

Attachments: ~WRD0000.jpg; image001.png; VI-AppE-RemedialSystemEmissions.xlsx; ChronicAcuteRBClatest.pdf;

Thanks Andrew. We believe these results for the influent and effluent testing indicate that breakthrough of the GAC filter is happening for cis-DCE and to a lesser extent TCE. PCE is more easily absorbed by the carbon resulting in desorption/pass thru of other VOCs. Thus we request that the effluent limits be established for PCE, TCE, cis- and trans-DCE. Appendix E in the new DEQ VI guidance lays out the protocol for evaluating discharges. It references an interactive excel spreadsheet which is difficult to find on our website, so I attached it here.

With regard to DEQ’s updated RBCs, the indoor air RBCs for chronic exposure have not changed. The updated guidance has added indoor air RBCs for acute exposure, which should be added to the indoor air data results tables in future reporting along with the chronic (which are the same we have been using). Soil gas RBCs and GW volatilization RBCs have been updated and are lower. These criteria will affect remediation confirmation testing (section 3.5 of the RAP). Rather than a target of 47,000 ug/m3 for PCE in soil gas based on the outdated RBC, the new soil gas criteria of 1,600 ug/m3 is applicable. It will take much longer, if ever, to meet that with the current system. Thus the testing and shutdown sequence outlined in the RAP would not ever be completed. We could look to close out the site but it would be conditioned on continued O&M of the fan and potentially building development restrictions, memorialized in an EES recorded on the property deed.

I have attached VI RBCs with acute and chronic air values, along with soil gas and GW volatilization.

Let us know if you have any questions on this or would like to discuss.

From: Andrew Blake <ablake@succeed-env.com>

Sent: Tuesday, March 12, 2024 2:48 PM

To: PUGH Mark * DEQ <Mark.PUGH@deq.oregon.gov>

Cc: Tera Heintz <teramheintz@yahoo.com>; NELSON Heidi * DEQ <Heidi.NELSON@deq.oregon.gov>; kumkang793 <kumkang793@gmail.com>; Lance Downs <AdvRemTech@canby.com>; Greg Brown <gregbrown@riverviewbank.com>

Subject: Re: Tie's Dry Cleaning (ECSI 6478) Update

Hi Mark,

Attached is Tie's second quarterly SSD system monitoring report for your review. Again, we collected two indoor air samples at the site. No VOCs were detected in the indoor air samples at concentrations that exceed the new RBCs. I anticipate that the next monitoring event will occur in May 2024. As always, we appreciate your team's guidance and support with this project. Thank you!

Sincerely,

Andrew S. Blake, R.G., L.G.

Principal Geologist

1631 NE Broadway, #211

Portland, Oregon 97232

Email: ablake@succeed-env.com

Cell: 971-371-0404

On Tue, Dec 19, 2023 at 9:53 AM PUGH Mark * DEQ <Mark.PUGH@deq.oregon.gov> wrote:

Andrew,

Thanks for the report. The 1,2 DCA hit appears linked to use in the fish store as you suggest. FYI, if a dry cleaning operation changes site use we would be concerned about PCE or TCE vapors off-gassing from the floor or building materials, even if they were not present in soil gas. E.g., we occasionally will have elevated PCE in a closed dry cleaner store converted to another use, even though it is not present in soil gas. If above RBCs we would still require remediation. Not the case here.

From: Andrew Blake <ablake@succeed-env.com>

Sent: Tuesday, December 12, 2023 9:40 PM

To: PUGH Mark * DEQ <Mark.PUGH@deq.oregon.gov>

Subject: Re: Tie's Dry Cleaning (ECSI 6478) Update

Good evening all!

SEC's first quarterly memorandum for the TIE's cleanup project is attached for your review. The first two indoor air samples are showing improvement. The VOC 1,2-dichloroethane was detected in the Fish Store air sample, but does not appear to originate from beneath the building’s floor slab (this compound has not been detected in any previous soil-gas samples or SVE effluent samples). No other VOCs were detected at concentrations greater than corresponding screening levels for the Subject Property. I'm very interested in your thoughts on this...

Overall, the system is still working as intended. We got SSD-8 running again. Thanks again and have a great evening!

Sincerely,

Andrew S. Blake, R.G., L.G.

Principal Geologist

1631 NE Broadway, #211

Portland, Oregon 97232

Email: ablake@succeed-env.com

Cell: 971-371-0404

On Fri, Oct 27, 2023 at 7:31 PM Andrew Blake <ablake@succeed-env.com> wrote:

Good evening everyone!

Attached is the second performance monitoring memorandum for the SSD system at Tie's. The cleanup is progressing nicely. Thanks and have a great weekend!

Sincerely,

Andrew S. Blake, R.G., L.G.

Principal Geologist

1631 NE Broadway, #211

Portland, Oregon 97232

Email: ablake@succeed-env.com

Cell: 971-371-0404

On Thu, Sep 21, 2023 at 9:36 AM Andrew Blake <ablake@succeed-env.com> wrote:

That time works for me! Thanks again!

Sincerely,

Andrew S. Blake, R.G., L.G.

Principal Geologist

1631 NE Broadway, #211

Portland, Oregon 97232

Email: ablake@succeed-env.com

Cell: 971-371-0404

On Thu, Sep 21, 2023 at 6:13 AM PUGH Mark * DEQ <Mark.PUGH@deq.oregon.gov> wrote:

Sounds good. Does Tuesday, Oct 24 at 9AM work for meeting?

From: Andrew Blake <ablake@succeed-env.com>

Sent: Wednesday, September 20, 2023 12:19 PM

To: PUGH Mark * DEQ <Mark.PUGH@deq.oregon.gov>

Subject: Re: Tie's Dry Cleaning (ECSI 6478) Update

Hi Mark,

Thank you for your comments! My responses are provided below:

* The collection of indoor air samples to evaluate system effectiveness makes sense. I will plan on collecting the requested indoor air samples during each quarterly events, until they are deemed unnecessary by DEQ. As you are aware, it appears that the only contaminants of concern are chlorinated VOCs (cVOCs). Going forward, would you be amenable to us analyzing future vapor and air samples for just cVOCs, rather than the full list of VOCs? Analyzing future samples for cVOCs only seems appropriate to me, and would help us keep laboratory costs down.
* Thank you for that comment! I agree and will cease the use of a PID at the surface points, but will continue to check pressures at these locations.
* I agree that the PID variability could be due to moisture. The sanitary sewer lines at the site appear to have been reconfigured (with new lines added) over time. I had a preliminary camera survey done before building the VES, and there are a few breaks in the old line, which primarily consists of iron pipes. I haven't seen moisture accumulation yet, but I will continue to check the knock-out drum for moisture content, and will add my findings to forthcoming O&M memoranda. Any accumulated liquid will be containerized for characterization and disposal, as directed.
* Regarding figure 2, I make the requested edits, and will add the additional figure. I agree that is a busy figure. Thank you!
* I will update Table 4, as requested.
* I will update Table 7, as requested.
* I will update Table 8, as requested
* Thank you for letting me know about that remnant file name! I'll get it removed.

Thank you again for providing these comments! The first Quarterly O&M event will occur in early November, but I'll conduct the next monthly O&M event in early October. I should have October's effluent sample lab results by October 20th. Should we schedule a meeting for October 20 or shortly thereafter?

Sincerely,

Andrew S. Blake, R.G., L.G.

Principal Geologist

Error! Filename not specified.

1631 NE Broadway, #211

Portland, Oregon 97232

Email: ablake@succeed-env.com

Cell: 971-371-0404

On Tue, Sep 19, 2023 at 10:19 AM PUGH Mark * DEQ <Mark.PUGH@deq.oregon.gov> wrote:

Andrew, thanks for the update. There is a lot of good info here. We have the following comments and recommendations. Please address as indicated, and let me know if you have any questions. It may be helpful to meet following the next O&M event. Thanks again!

* The initial purpose of the sub-slab probes is to verify ROI, which has been accomplished. Indoor air testing is the best line of evidence for system effectiveness. Indoor air testing is not included in the current work plan, which was an oversight on our part. Indoor air testing will be necessary for project closeout. Given that prior indoor air concentrations were up 6 times the applicable DEQ RBC, we recommend indoor air testing be integrated into the quarterly O&M and reporting. Let us know if this can be accommodated.

* PID readings from surficial points during fan operation typically don’t provide useful concentration info. However, following remediation these points will be used to assess ambient conditions/soil gas rebound with the fan off as a line of evidence to verify RAOs have been met and site is protective. No response needed.

* PID readings from sampling ports apparently were affected by moisture. The results of SSFISH, which appears to be near the source area, varied substantially. The “0” readings may be related to the higher vacuum and flow during the August 30 and September 6 events. If high humidity is the cause of the elevated PID readings this suggests that the sanitary sewer line may be leaking or there is some other mechanism resulting in high humidity. The high apparent “false-positives” hamper assessing the status of the GAC and predictions on its life span. This is especially important when using a filter system with only one GAC drum. We recommend a camera survey to assess the integrity of the sewer line and its potential to impart moisture into the system. It is common for older lines to develop leaks, particularly at joints and/or bends/angles in the pipe. Also, the knock-out drum should be checked and tracked for moisture content (presumably it should have accumulation). Accumulated liquid should be containerized for subsequent characterization and disposal. If there are detectable levels of PCE or TCE then it is a listed hazardous waste, but if lower than TCLP level (14 mg/L and 10mg/L, respectively) it can be disposed as solid waste with DEQ approval. Please respond.

A flame-ionization detector or Draeger type adsorbent tubes are less prone to moisture interference and could be tried instead of a PID. Additional collection of effluent for laboratory analysis may be needed until the confidence in field readings improves. No response necessary.

* As far as system fine tuning, consider closing one or more ball valves for a short time, like SSD-8 that isn’t doing much, and see if that results in a larger vacuum in apparent source areas (e.g., near SSFish). No response necessary.

* Figure 2. Please label the vapor monitoring points. Consider separating the SSDS figure from discharge detail to improve legibility.

* Table 4. The recorded velocity was measured between 380 feet/min and 540 feet/min – the baseline velocity used for the modeled discharge was 1.43 m/s, which is lower than what has been recorded. Please update the AERSCREEN calculations using the measured system velocities. Update Table 4 value in Table 8 as appropriate.

* Table 7. Please indicate the precision of the pressure gauges used to collect these measurements.

* Table 8. Please revisit the Table 4 values that are referenced here considering the actual measured discharge values for flow/velocity.

* “GEODESIGN” appears as the file name when the document is open.

From: Andrew Blake <ablake@succeed-env.com>

Sent: Friday, September 8, 2023 2:40 PM

To: PUGH Mark * DEQ <Mark.PUGH@deq.oregon.gov>

Cc: Tera Heintz <teramheintz@yahoo.com>; NELSON Heidi * DEQ <Heidi.NELSON@deq.oregon.gov>; kumkang793 <kumkang793@gmail.com>; Lance Downs <AdvRemTech@canby.com>

Subject: Re: Tie's Dry Cleaning (ECSI 6478) Update

Hi Mark,

Thank you for your email last week! I just performed the fourth weekly monitoring event on Wednesday. Attached is a memorandum summarizing the first month of system monitoring at the site. The site plan shows the layout of the system with the requested knockout and GAC shown. I apologize for not sending that earlier! Lance prepared those details in June and I thought I sent it to you (but alas). I'm planning on sending you another memorandum in early October, so feel free to let me know if DEQ would like me to add any additional information to the forthcoming memo, or would like anything in the interim. As always, I appreciate all of your assistance with this project. Thank you!

Sincerely,

Andrew S. Blake, R.G., L.G.

Principal Geologist