41 Hutchins Drive

Portland, Maine 04102

www.woodardcurran.com 

T 800.426.4262 

T 207.774.2112 

F 207.774.6635

CMP O’Connor (222350) September 2009 

Water Level Study 

MEMORANDUM

TO: Roy Koster (CMP) 

FROM: Josh Bowe, Geologist

DATE: September 15, 2009 

RE: Water Level Study, O’Connor Company Superfund Site, Augusta, Maine 

Woodard & Curran recently completed a groundwater level study at the O’Connor Superfund Site in 

Augusta, Maine. The study was conducted to evaluate the potential impact that blasting along Route 17 may 

have on the on-site bedrock groundwater plume. 

On July 24, 2009 Josh Bowe (Woodard & Curran) deployed automated pressure transducers in two on-site 

monitoring wells (OW-202B and OW-302B) approximately three days prior to the initiation of the blasting. 

Manual water level readings were collected and transducers were programmed and installed in the two 

monitoring wells. Transducers were programmed to collect water levels and temperature readings on a fiveminute interval. A barometric logger was deployed in OW-302B above the water table and the data from the 

logger was used to compensate water level data for changes in barometric pressure. In addition, 

precipitation data were downloaded from the Augusta NOAA weather station ID# 170275 located at the 

Augusta Airport. Blasting on Route 17 adjacent to the O’Connor Site began on July 27th and W&C remobilized to the site on July 28th to download ambient water level data from the transducers and ensure 

proper operation. Blasting ceased near the site on July 29th and W&C mobilized to the site after blasting 

completion to download complete water level data sets . The transducers remained in place and recorded 

data through the month of August until their removal on September 3rd. Drilling and blasting logs were 

collected from D&C Construction to correlate blasting events to groundwater level and temperature data. 

Attached to this memorandum are four time series graphs for OW-202B and OW-302B depicting 

groundwater level, groundwater temperature, and precipitation trends before, during, and after the blasting 

periods. In summary, Chart 1 for OW-202B and OW-302B show groundwater levels rising over the three 

day period prior to blasting. Groundwater levels steadily increased in response to a significant precipitation 

event on July 24th when the area received approximately 1.6 inches of precipitation. Groundwater levels 

generally remained steady while blasting was conducted July 27th through July 29th. Natural groundwater 

level cycles were observed in the two bedrock wells and are not attributed to blasting activities. After the 

blasting period, groundwater levels continued to rise after subsequent precipitation events on July 26th ,27th, 

and July 31st. Groundwater level trends display a seasonal decrease during the month of August as a result 

of periods of reduced precipitation and limited recharge. Chart 2 for OW-202B and OW-302B display 

groundwater temperature trends for the period of record and indicate that groundwater temperatures 

remained steady and did not fluctuate greater than 0.1 degrees Celsius. 

Based on the recorded groundwater data and observed natural water level trends, W&C concludes that 

blasting activities conducted adjacent to the O’Connor Superfund Site along the Route 17 corridor did not 

result in any significant or sudden changes in groundwater levels or temperatures. The transducers were 

removed from the on-site monitoring wells on September 3rd. 

cc: Roy Koster (CMP) 

Henri Vincent (W&C) 

 Lori Moreau (W&C) 
CHART 1 

Groundwater Levels at 

OW-202B and OW-302B 
OW-202B Groundwater Level vs. Blasting Events and Daily Precipitation

1415161718192021222324

7/24/09 7/28/09 8/2/09 8/6/09 8/11/09 8/15/09 8/20/09 8/24/09 8/29/09 9/2/09

Water Level (feet below measuring point)

00.511.522.533.544.55

Daily Precipitation (inches)

Route 17 Blasting Events Natural Cycles
OW-302B Groundwater Level vs. Blasting Events and Daily Precipitation

1819202122232425262728

7/24/09 7/28/09 8/2/09 8/6/09 8/11/09 8/15/09 8/20/09 8/24/09 8/29/09 9/2/09

Water Level (feet below measuring point)

00.511.522.533.544.55

Daily Precipitation (inches)

Route 17 Blasting Events

Natural Cycles
CHART 2 

Groundwater Temperatures at 

OW-202B and OW-302B 
OW-202B Groundwater Temperature vs. Blasting Events

56789

101112131415

7/24/09 7/28/09 8/2/09 8/6/09 8/11/09 8/15/09 8/20/09 8/24/09 8/29/09 9/2/09

Groundwater Temperature (C) B

G

Route 17 Blasting Events
OW-302B Groundwater Temperature vs. Blasting Events

56789

101112131415

7/24/09 7/28/09 8/2/09 8/6/09 8/11/09 8/15/09 8/20/09 8/24/09 8/29/09 9/2/09

Groundwater Temperature (C) B

G

Route 17 Blasting Events