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EXERCISE ONLY - Diesel fuel spill on Shenandoah River at Rt 50.

Jim Palmer <jpalmer@...>
 

NEW EXERCISE

Tanker truck involved in an accident and is overturned on Rt 50 where it crosses the Shenandoah River near Berrys, VA at 8 am this morning. The truck is leaking but an unknown amount of diesel has reached the river with a visible sheen. Emergency responders are on scene but the leak is not under control at this time. Travel time estimates will be provided shortly. NOTE: Some utilities and agencies receiving this message are upstream of the spill but are included for information purposes.

Please acknowledge receipt by replying to this message.

Carlton Haywood
 

I read the message at 1:11 p.m.

--
Carlton Haywood
Executive Director

Interstate Commission on the Potomac River Basin
Mail:  30 West Gude Drive Suite 450, Rockville, MD   20850-1180
Phone: 301-274-8105
Fax: 301-576-3802
Website Facebook Twitter

Curtis Dalpra
 

received

On Tue, Jan 23, 2018 at 1:11 PM, Jim Palmer <jpalmer@...> wrote:
NEW EXERCISE

Tanker truck involved in an accident and is overturned on Rt 50 where it crosses the Shenandoah River near Berrys, VA at 8 am this morning. The truck is leaking but an unknown amount of diesel has reached the river with a visible sheen. Emergency responders are on scene but the leak is not under control at this time. Travel time estimates will be provided shortly. NOTE: Some utilities and agencies receiving this message are upstream of the spill but are included for information purposes.

Please acknowledge receipt by replying to this message.




--
Curtis Dalpra
Communications Manager

ICPRB
30 W. Gude Drive, Suite 450
Rockville, MD 20850


(301) 274-8107
web: www.potomacriver.org

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Jim Palmer <jpalmer@...>
 

ICPRB staff have completed an initial assessment of travel times to downstream intakes for this event. Further

updates will be provided as needed.  Reply to this message if you have any questions or have additional

information to share. 

 

Initial spill event occurred on 01/23/18 at 0800 hours.

Spill material: diesel fuel

Spill duration: 4 hours

Location: 39.040926, -77.999508 (Paste this Lat. and Long. into Google Maps to see spill location)

Event description: Diesel tanker truck with capacity of 11,000 gals overturned on Rt 50 where it crosses Shenandoah River near Berrys, Va. Tanker is leaking with product into the river. Emergency responders on scene but leak not under control.

 

Estimated arrival times and peak concentrations at downstream intakes after spill on 01/23/18 at 0800 hours.

- Arrival estimates are rounded to the nearest half hour.
- Travel times and concentrations are estimates and should be used solely as guidelines.
- Peak concentration values do not include pre-spill ambient concentrations.
- Each utility should monitor actual water conditions.
- See model assumptions below to properly interpret travel time and concentration estimates.

 

Unless otherwise indicated, the model is based on the following assumptions:

1. Spill material is dissolved and instantly and uniformly mixed across a stream channel and through the water column at the initial spill point and also when a tributary joins a larger stream.

2. Spill material is either conservative or, if there are losses due to volatilization, chemical decay, or deposition, then those losses may be represented as an exponential decay process.

3. Streamflows are constant throughout the modeled time period.

4. Bacteria concentrations are modeled with a temperature-dependent exponential decay.

 

In addition to the above assumptions, very high or very low river flows can affect model accuracy.  Accuracy also is dependent on the quality of information provided, including spill location, contaminant type and amount, and duration of event.


Diesel fuel is a mixture of many components, some float and other mix within the water column. Surface sheen may be affected by wind or surface obstructions but the dissolved components are not. Absence of surface sheen does not
necessarily indicate no contaminant.

The current flows on the Shenandoah is within the model calibrated range. The Potomac flow is above the calibrated range. Potomac flow appears to be rising while the Shenandoah flow may be leveling off.

Shenandoah River Travel Times

Leading Edge Arrival (mil time)

Duration (hours)

Peak (hours after LE)

Peak Conc. (ppm)

Intake: Berryville, VA

Jan 24, 0430

8

4

99

Intake: Charles Town, WV

Jan 25, 1330

16

8

67

USGS Gage 01636500 Millville

Jan 26, 0100

20

10

48

WWTP:  Harpers Ferry

Jan 26, 1230

25

13

43

US 340 Bridge

Jan 26, 1230

25

13

43

Mouth

Jan 26, 1500

26

14

41

 

Potomac River Travel Times

Leading Edge Arrival (mil time)

Duration (hours)

Peak (hours after LE)

Peak Conc. (ppm)

Intake: Brunswick, MD

Jan 26, 2100

29

14

6

Intake: Fred. Co., MD

Jan 27, 0800

32

14

5

Intake: Leesburg, VA

Jan 27, 2000

34

15

4

Intake: Fairfax Water, VA

Jan 28, 0700

36

17

4

Intake: WSSC, MD

Jan 28, 1430

40

18

3

Intake: Rockville, MD

Jan 28, 1700

41

18

3

Intake: WA Gt Falls

Jan 28, 1930

42

18

3

Intake: WA Lt Falls

Jan 29, 0900

49

20

3

 

Cherie Schultz
 

I read the message at 1:50 pm

Sent from my iPhone

On Jan 23, 2018, at 1:11 PM, Jim Palmer <jpalmer@...> wrote:

NEW EXERCISE

Tanker truck involved in an accident and is overturned on Rt 50 where it crosses the Shenandoah River near Berrys, VA at 8 am this morning. The truck is leaking but an unknown amount of diesel has reached the river with a visible sheen. Emergency responders are on scene but the leak is not under control at this time. Travel time estimates will be provided shortly. NOTE: Some utilities and agencies receiving this message are upstream of the spill but are included for information purposes.

Please acknowledge receipt by replying to this message.

Carlton Haywood
 

Should note in your message that you computed peak concentrations assuming that all contents of tanker discharged to river, if that's what you did..  Thus, this is a worst case prediction.

I replicated your information in my spreadsheet and my results show a 1 hour shorter duration at each downstream point and corresponding higher peak concentrations.  Curious that we got different results using the same model.  Are these your inputs?
River Mile = 37.8
Spill amount 10,400 liters/hour for 4 hours
Flow at Front Royal gage:  536



--
Carlton Haywood
Executive Director

Interstate Commission on the Potomac River Basin
Mail:  30 West Gude Drive Suite 450, Rockville, MD   20850-1180
Phone: 301-274-8105
Fax: 301-576-3802
Website Facebook Twitter

Jim Palmer <jpalmer@...>
 

I used 10,400 liters/hr for 5 hours, it was 1:00 when I put all the data in the model and this is the time the message would go out. The other inputs are the same. Yes, I did assume the whole tanker was discharged into the river, worst case.


On Tue, Jan 23, 2018 at 2:03 PM, Carlton Haywood <chaywood@...> wrote:
Should note in your message that you computed peak concentrations assuming that all contents of tanker discharged to river, if that's what you did..  Thus, this is a worst case prediction.

I replicated your information in my spreadsheet and my results show a 1 hour shorter duration at each downstream point and corresponding higher peak concentrations.  Curious that we got different results using the same model.  Are these your inputs?
River Mile = 37.8
Spill amount 10,400 liters/hour for 4 hours
Flow at Front Royal gage:  536



--
Carlton Haywood
Executive Director

Interstate Commission on the Potomac River Basin




--
Jim Palmer
Senior Hydrogeologist
Interstate Commission on the Potomac River Basin
30 W. Gude Dr., Suite 450
Rockville, MD 20850
301.274.8104
jpalmer@...