HydroCon, LLC | 510 Allen St, Suite B | Kelso, WA 98626 | Phone: 360.703.6079 | Fax: 360.703.6086

TECHNICAL MEMORANDUM

To: Mandy Lill

From: Craig Hultgren

Date: May 2, 2016

Subject: Assessment of the Location of Underground Storage Tanks at 1435 Guild Road, Woodland,

Washington

HydroCon Environmental, LLC (HydroCon) has prepared this memorandum to document research and investigative tasks performed to locate underground storage tanks (USTs) that were reportedly located at the property located at 1435 Guild Road in Woodland, Washington [the Property (Figure 1)]. This memorandum provides a brief background summarizing the history of ownership and land use, findings of a Phase I Environmental Site Assessment (ESA) report prepared by PBS Engineering and Environmental (PBS) for the Property1, interviews with former employees at the farm, and field work performed by HydroCon to locate USTs. Site features including the location of buildings and infrastructure (i.e., water supply well, roads, etc.) and areas of investigation are shown on Figure 2.

Background

The Port of Woodland is developing a Master Site Plan for the Guild Road Industrial Park on property owned by the Port of Woodland, commonly referred to as the “Rose Growers” property located at 1435 Guild Road in Woodland, Washington. The Port of Woodland has divided the overall project into two phases: Phase 1: Preliminary Environmental Work for the Master Site Plan and Phase 2: Design, Engineering and Permitting for the Master Site Plan. Under the terms and conditions set forth by the U.S. Department of Commerce, Economic Development Administration (EDA), the Port of Woodland must complete preliminary environmental work prior to initiating the Design, Engineering and Permitting of the Master Site Plan. HydroCon has been contracted to provide satisfactory evidence of determination of location of USTs and associated piping at the site.

Phase I Environmental Site Assessment Report

A Phase I ESA report on the Property was prepared by PBS in June 2005. The text of the report was provided to HydroCon to assist in performing the task of locating USTs at the property. No figures or attachments were provided. A summary of applicable report content is provided below.

Site History

According to the Phase I ESA report, the subject property was used for agricultural purposes since 1912. Originally it was used as a dairy farm. In the mid-1940s the property was part of the larger "United Bulb Company”. A metal building was constructed on the Property in the late 1960s (herein referred to as the “Old Building”) and was used for packing and shipping. The size of the building was expanded to the south (herein referred to as the “New Building”) shortly after construction of the “Old Building”. Northwest Roses purchased the business from United Bulb Company. The property was not included in the sale. From the late 1970’s until 2004, Northwest Roses leased the subject property and used the

1 PBS Engineering and Environmental. Phase I Environmental Site Assessment Report, 1435 Guild Road, Woodland, Washington.

Prepared for the Port of Woodland, Washington. June 2005.

site to store, package and ship dormant roses, blueberries and other plants. Open areas of the site were used to store nursery stock. In late 2004 the business moved its equipment and stock to a nearby property. The site remains in agricultural use.

References to Underground and Above Ground Storage Tanks

PBS performed a site visit in 2005 to observe existing site conditions, including features that may indicate the presence of fuel storage tanks. The following tanks were observed:

A tank with an estimated capacity of 275 gallons was observed on the ground surface near the northwest corner of the farm building with other pieces of equipment or scrap metal. The tank appeared to be empty and no petroleum odor was detected at the tank openings. The tank was painted and it was PBS’s opinion that it had the appearance of being an above-ground storage tank (AST).

A tank shell with an estimated capacity of 2,000 gallons was observed stored on the ground near the Pump House. A fuel pump was observed adjacent to the Pump House. The equipment did not appear to be functional and was mounted to a concrete pad in a thickly overgrown area.

A "fuel oil" fill pipe was observed in the packing shed, across the wall from the furnace. A vent pipe was not observed.

Interviews

PBS conducted interviews with people knowledgeable about the operations at the site (Mr. Monty McGuire, Mr. Horatio Arce and Mr. Rigo Arce). Mr. Dale Boon (Port of Woodland Commissioner District 1) interviewed the former maintenance supervisor of the farm (Mr. Ernie Heidigger). A summary of these interviews is included below: Mr. Monty McGuire was contacted by PBS on June 9, 2005. He provided the following information about the Property:

The first section of the building was constructed in about 1969-70, the second and third sections about a year apart following that.

The buildings weren't heated.

He didn’t remember the tanks observed by PBS on the property. He thought that they may have been underground at one time and were used to fuel trucks and tractors.

Mr. Horatio Arce and his brother Rigo were interviewed by PBS on June 14 and 15, 2005. They worked on the site for approximately 10 years. The following information was provided:

A 350-gallon diesel AST was in use at the site for 10 years. The tank was removed from the property and placed at the property they currently lease. When in use it was located near the pump house on the east property boundary. The AST was equipped with a pump.

Two USTs are present on the site, a fuel tank located beneath or next to the Pump House and a heating oil tank located beneath the Buildings. The fuel pump was never in use during their time on the site.

They did not know if the large tank located near the north Pump House was once underground or associated with the fuel pump.

Horatio could not recall the furnace being used. He could not recall the heating oil tank being filled.

Mr. Ernie Heidigger was interviewed by Mr. Dale Boon in April 2016. He was Maintenance Supervisor at the farm for 30 years.

He was 99% certain there were no USTs on the property.

Fieldwork

HydroCon performed several field tasks in an effort to locate buried tanks at the Property. A discussion of these field tasks are provided below.

Site Reconnaissance

HydroCon performed site reconnaissance on three occasions during the investigation. The purpose of these site walks was to look for evidence of possible USTs (fill and vent piping, pumps, etc.) including areas that were discussed in the Phase I ESA report (near the Pump House and inside the “Packing Shed”) as well as likely locations around the Buildings where a heating oil tank would be located. A summary of the site walks is provided below.

A site walk was performed on March 23, 2016 with the Ecological Land Services (ELS) Project Team and the Executive Director of the Port of Woodland (Ms. Jennifer Keene) after the completion of the Project Kick Off meeting. HydroCon observed the following:

Piping stubbing out of the ground near the well Pump House which had the appearance of either an electrical conduit or possible a product line (Figure 2 and Figure 3, Photo 5).

2 pipes side by side that are stubbing out of the ground near the northwest corner of the “New Building” (Figure 3, Photo 1).

A tank shell measuring 72” in diameter by 108” in length is located next to a Connex box near the Pump House (Figure 3, Photo 8). Based on the dimensions of the tank, the capacity is approximately 2,000 gallons.

A second site walk was performed prior to performing the geophysical surveys on April 15, 2016. HydroCon personnel, along with the crew from Pacific Geophysics, walked around the 2 Buildings, Pump House area, and nursery stock storage area looking for evidence of possible USTs (e.g., fill and vent pipes, pumps, etc.). The following observations were noted:

The paint marks from the 1-Call utility locates were visible on the ground. Natural gas and electricity enters the “New Building” near the southwestern corner of the building. This may be the source of heat in the Buildings (possibly replacing the use of heating oil).

Other than the piping seen during the March 23rd site walk, no other features were observed that could indicate the presence of USTs.

The third reconnaissance of the Property was performed on April 27, 2016 after the fieldwork was completed. Results of that trip are documented in detail below.

Underground Utility Locates

Prior to the commencement of subsurface activities, a public utility notification was requested through the Washington One Call service (Locate ticket number: 16103804). HydroCon placed white markings at the site to identify areas where locates were requested, as required by law.

Geophysical Surveys

HydroCon contracted with Pacific Geophysics (PG) to perform geophysical surveys in selected areas of the site that were identified as having the potential for having a buried tank (either in the Phase I ESA report or observations made during Site Reconnaissance). The location of the surveys is shown on Figure 2. The surveys consisted of using ground penetrating radar (GPR) and hand-held electromagnetic (EM) detection sensors (Figure 3, Photo 3). A tracked excavator was used to pothole areas where the EM sensors indicated the presence of metallic objects (Figure 3, Photo 7). A detailed description of the methodology and results of the surveys are included in PG’s survey report (Attachment A).

Results of the surveys are summarized below:

No USTs are present in the areas surveyed.

The diameter of the 2 pipes located at the northwest corner of the “Old Building” is too small to be associated with a UST.

A concrete slab is located near the Pump House. This structure appears to be either a pump island or component of an AST. An electrical conduit line is present (Figure 3, Photo 5).

The soil underlying the concrete slab consists of silty sand and gravel fill. This could potentially be the backfill cavity of a former UST.

An old burn pit was discovered about 15 to 20 feet northeast of the Pump House. Metal piping resembling a product line was found in this area of the site (Figure 3, Photo 6). This pipe is believed to be associated with the former AST.

Inspection Inside Buildings

On April 27, 2016, HydroCon was provided access inside the two Buildings. The following observations were noted:

Floor drains are present near the eastern end of the “New Building” (Figure 2 and Figure 3, Photo 4). The purpose of these drains is unknown. The drains are assumed to drain into the septic system. No petroleum odor or staining was observed.

A fill pipe located in between the two exterior walls of the “Old Building” and “New Building” was observed (Figure 2 and Figure 3, Photos 2 and 11). The cap on top of the fill pipe says “Fuel Oil” (Figure 3, Photo 10).

HydroCon opened the cap and attempted to lower an electronic oil/water interface probe into the tank to measure the depth to product/water and assess what petroleum fuel product was being stored in the tank. The probe could not be lowered into the tank due to the presence of cement. It appears the tank has been closed in-place. The cap had an odor that resembled heating oil. The tank is located below the concrete floor and the dimensions can’t be measured at this time.

Discussion of Results

One UST that contained heating oil was located at the Property located between the “Old” and “New Building

(Figure 2). The tank has been filled with concrete (i.e., “closed in-place”). A tank used to distribute fuel

(probably diesel) was located near the Pump House. A concrete pad and product piping was observed in

this area of the site as well as electrical conduit line. The tank is no longer located there. Granular fill soil

underlies the concrete pad. This imported soil may have been placed to fill the UST cavity or it may have

been used as sub base for the pump pad. Based on historical documentation, an AST once operated at this

location.

A thorough GPR survey was performed at the most likely locations that a UST would be located at the

Property (based on proximity to the site Buildings and access road and documentation found in the Phase I

ESA report). No USTs or significant magnetic anomalies were observed in the surveys.

Recommended Action During Site Demolition

If a UST is encountered during site demolition, HydroCon recommends that the construction contractor stop work near the tank location and contact the Port of Woodland representative immediately. If fuel is observed to be leaking from the tank, placement of absorbent socks is recommended to mitigate the spread of product. An environmental consultant licensed as a Washington State Site Assessor (HydroCon) should be contacted to supervise the proper decommissioning of the tank, management of the waste, and disposal of the tank shell.

FIGURES

NOTE(S):

USGS, DEER ISLAND QUADRANGLE

OREGON-WASHINGTON

7.5 MINUTE SERIES (TOPOGRAPHIC)

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FIGURE 1

SITE LOCATION MAP

PORT OF WOODLAND

1435 GUILD ROAD

WOODLAND, WA

SITE

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"Old Building"

"New Building"

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Shed"

EM Survey

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Well Pump

House

Metal Trailer

AST

Transformer

Electric Conduit

Old Furnace Location

(now removed)

Entrance

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Fill Pipe

Floor Drains

Well #2

Burn Pit

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SITE FEATURES

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WOODLAND, WA

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BUILDING

GPR SURVEY LOCATIONS

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PHOTO 1

Two pipes at NW corner of "Old Building".

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PHOTOPLATE 1

SITE PHOTOGRAPHS

PORT OF WOODLAND

1435 GUILD ROAD

WOODLAND, WA

PHOTO 2

Fill pipe of heating oil tank located between

stacked pallets and wall between "NEW" and

"OLD" building infrastructure.

PHOTO 3

GPR Setup, North sife of "Old Building".

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Floor drains, NE quarter of "New building".

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PHOTOPLATE 2

SITE PHOTOGRAPHS

PORT OF WOODLAND

1435 GUILD ROAD

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PHOTO 5

Piping near Pump House, Probable location of

above ground storage tank.

PHOTO 6

Possible Product pipe presumed to be associated

with above ground storage tank. Located east of

Pump House near former Burn Pit.

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Potholing, used to assess magnetic signatures from

Electro Magnetic Survey.

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SITE PHOTOGRAPHS

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Abandoned 2,000-gallon tank, Metal Shed and

Pump House.

PHOTO 9

Wide angle view of the inside of the "New Building". Heating oil tank located under far

wall in between "OLD" and "NEW" buildings.

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Cap of fill pipe of heating oil tank.

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PHOTO 11

Fill pipe of heating oil tank after debris has been

removed from that area of the site.

ATTACHMENT A

Pacific Geophysics – Geophysical Survey Letter Report

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the pipe. The pipe was electronically “traced” using an RD8000PDL pipe and cable locator. The pipe was traced toward the northwest for 4-6 feet. No USTs were detected in this survey area. A second area was scanned using the hand-held instruments only. This area was located near a small wooden pump house located SE of the main building. North of the structure were seen a suspicious metal pipe and an electric conduit. Both features were surrounded by a concrete pad thought to be a possible pump-dispenser island. The pipe was loose and did not appear to be attached to a UST. No buried objects were detected using the two hand-held instruments. A track hoe was used to clear a thicket of berry bushes growing near the features. The track hoe also cut a shallow trench east of the concrete pad. A metal-reinforced rubber hose was discovered attached to the metal pipe. The scan was expanded to the north and east about 20 feet. No large 3D objects were detected. Based on these results we believe the concrete pad is probably a pump island, and the metal pipe is a pump product line. The hose is probably a product line from a nearby above-ground storage tank (AST). Jeff Mann and Nikos Tzetos of Pacific Geophysics conducted the survey for Mr. Craig Hultgren of HydroCon/ELS on April 15, 2016. Mr. Christopher Daschel of HydroCon/ELS was on Site during the survey. This letter report was written by Jeff Mann, reviewed by Nikos Tzetos and sent to Mr. Hultgren on April 20, 2016.

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Appendix A. Geophysical Survey Methods Magnetometer Surveys Small disturbances in the Earth’s local magnetic field are called “magnetic anomalies”. These may be caused by naturally occurring features such as metallic mineral ore bodies, or from manmade features such as metal buildings, vehicles, fences, and underground storage tanks. The magnetometer only detects changes produced by ferrous objects. Aluminum and brass are non-ferrous metals and cannot be detected using a magnetometer. A magnetometer is an electronic instrument designed to detect small changes in the Earth’s local magnetic field. Over the years different technologies have been used in magnetometers. The Geometrics G-858 Portable Cesium Magnetometer used to collect magnetic data for Pacific Geophysics uses one of the most recent methods to detect magnetic anomalies. A detailed discussion describing the method this unit uses is available at Geometrics.com. This magnetometer enables the operator to collect data rapidly and continuously rather than the older instruments that collected data at discreet points only. The G-858 is carried by hand across the site. The sensor is carried at waist level. Typically individual data points collected at normal walking speed are about 6” apart along survey lines usually 5 feet apart, depending on the dimensions of the target objects. It is critical to know the exact location of each data point so that if an anomaly is detected it can be accurately plotted on a magnetic contour map. At most small sites, data are collected along straight, parallel survey lines set up on the site before the data collection stage begins. For very large, complex sites, the G-858 can be connected to a Global Positioning System (GPS) antenna which allows the operator to collect accurately-located data without establishing a survey grid. With GPS, data are collected and positioned wherever the operator walks. A limitation using GPS is that the GPS antenna must have line of sight with the GPS satellites. Data can be mislocated if the GPS antenna is under trees or near tall buildings. Data are stored in the unit’s memory for later downloading and processing. A magnetic contour map of the data is plotted in the field. Geographical features are plotted on the map. Magnetic anomalies appearing to be caused by objects of interest are then investigated on the site using several small hand-held metal detectors. If an object appears to be a possible object of interest, it may be investigated with GPR. Magnetic contour maps may be printed in color in order to highlight anomalies caused by ferrous objects located under the magnetic sensor. Usually, ferrous objects situated below the sensor produce magnetic “highs” and anomalies located above the sensor produce magnetic “lows”. Magnetic highs are of interest to the operator since most objects of interest are located underground. Depending on the orientation, shape and mass of a metallic object, a high/low pair of magnetic anomalies may be present. In the northern hemisphere the magnetic low is located north of the object and the magnetic high toward the south. The object producing the anomaly is located part way between the high and the low anomalies. Magnetometer surveys have limitations. Magnetometers only detect objects made of ferrous (iron-containing) metal. Large ferrous objects (buildings, cars, fences, etc.) within several feet of the magnetometer create interference that may hide the anomaly produced by a nearby object of interest.

Ground Penetrating Radar A Geophysical Survey Systems, Inc. (GSSI) SIR-2000 GPR system coupled to a 270-, 400-, or 900-MHz GSSI antenna is used to obtain the radar data for our surveys. GPR antennas both transmit and receive electromagnetic energy. EM energy is transmitted into the material the antenna passes over. A portion of that energy is reflected back to the antenna and amplified. Reflections are displayed in real-time in a continuous cross section. Reflections are produced where there is a sufficient electrical contrast between two materials. Changes in the electrical properties (namely the dielectric constant) that produce radar reflections include the moisture content, porosity, mineralogy, and texture of the material. Metallic objects of interest exhibit a strong electrical contrast with the surrounding material and thus produce relatively strong reflections. Non-metallic objects of interest (septic tanks, cesspools, dry wells, PVC and clay tile pipes) are not always good reflectors. Radar data are ambiguous. It can be difficult to distinguish the reflection produced by an object of interest from the reflection caused by some natural feature. Rocks or tree roots have reflections that appear similar to reflections from pipes. In concrete investigations reflections produced by metal rebar look exactly like those from electrical conduit or post-tension cables. Objects with too small an electrical contrast may produce no reflections at all and may be missed. Target objects buried below objects with contrasting properties that also produce reflections may be missed (e.g. USTs below roots, concrete pieces, pipes or rocks). If an object of interest like a UST is buried below the depth of penetration of the radar signal, it will be missed. In addition to interpreting ambiguous data, radar has several limitations that cannot be controlled by the operator. The radar signal is severely attenuated by electrically conductive material, including wet, clay-rich soil and reinforced concrete. The quality of the data is affected by the surface conditions over which the antenna is pulled. Ideally the antenna should rest firmly on a smooth surface. Rough terrain and tall grass reduce the quality of radar data. It is the job of an experienced interpreter to examine the GPR profiles and deduce if reflections are from objects of interest. A GPR interpreter cannot see underground, but can only interpret reflections based on experience. The only way to truly identify an object is to excavate. Hand-held Metal detectors Two small, non-recording metal detectors are used to locate suspect magnetic anomalies detected using the G-858 Magnetometer in order to determine the likely cause of the anomaly. First, the magnetic contour map and a Schonstedt Magnetic Gradiometer are used to locate the center of the magnetic anomalies. Once the anomaly is located an Aqua-Tronics Tracer is used to determine if the object producing the anomaly is a possible object of interest. Most anomalies are at least in part produced by features observed on the ground surface. Schonstedt Magnetic Gradiometer: This magnetometer has two magnetic sensors separated vertically by 10”. The magnetic field surrounding a ferrous object is strongest near the object and decreases rapidly as the distance increases. If the magnitude measured by the sensor located in the tip of the Schonstedt is very high, and the magnetic field measured by the sensor located farther up the shaft of the

Schonstedt is low, there is a large vertical magnetic gradient and the instrument responds with a loud whistle indicating the object is near the surface. If there is a small difference in the magnitudes measured by the two sensors, the object is deeper. The instrument responds with a softer tone. A discussion of this instrument is available at Schonstedt.com. Aqua-Tronics A-6 Tracer: The Aqua-Tronics A-6 Tracer uses a different method of detecting metallic objects. This instrument measures the electrical conductivity of a metal object. It is capable of detecting any electrically conductive metal, including non-ferrous aluminum and brass. The Tracer is capable of detecting three-dimensional objects as well as pipes. The Tracer consists of a transmitter coil and a receiver coil. In the absence of any electrically conductive material in the vicinity of the Tracer, the electromagnetic field around each coil is balanced. Basically the electromagnetic field produced by the transmitter induces an electric current into the area surrounding the instrument. Nearby conductive objects distort the EM field. The balance between the two coils is disturbed and the instrument produces an audible tone and meter indication.