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Operation and Maintenance Plan - AOC-65 Soil Vapor Extraction System, October 2003

Table of Contents

Section 1 - Introduction and Summary of Remedial Design

Section 2 - Site Conditions

2.1   Backgound

2.2   Site Delineation

2.3   Air Emissions

Section 3 - System Description

3.1   Vacuum System and Appurtenances

3.1.1   Vacuum Blowers

3.1.2   Moisture Separators

3.1.3   Blower Inlet Filter

3.2   Emissions Control

3.2.1   Recovered Vapor Treatment (Granular Activated Carbon Adsorption Unit)

3.2.2   Recovered Liquid Treatment

3.3   Monitoring and Control Equipment

3.3.1   Vacuum Gauges

3.3.2   Flow Control Equipment

4.1   System Start-up

4.2   Operation and Monitoring

4.3   Performance Data

4.3.1   VEW, Exhaust Emissions and Soil Vapor

4.3.2   Quarterly Data Collection

4.3.3   Flows and Pressures

4.4   Operation/Maintenance Monitoring

4.4.1   Twice Monthly and Monthly Monitoring Visits

4.4.2   Vent Well Air Flow Rate

4.5   Monitoring Schedule

Section 5 - System Maintenance

5.1   Vacuum Blower, Piping and Instrumentation

5.1.1   Vacuum Blowers

5.1.2   Piping

5.1.3   Maintenance Schedule

Section 6 - Reporting Requirements

Section 7 - Bibliography and References

Figures

Figure 2.1   AOC-65 SVE System Layout

Figure 3.1   Blower System Instrumentation

Figure 3.2   Blower Area Plan and Section

Tables

Table 3.1   SVE Equipment Specifications

Table 4.1   Monitoring Schedule

Appendices

Appendix A   Manufacturer's Equipment Information

Appendix B   Data Collection Sheets

Abbreviations and Acronyms

Section 1 - Introduction and Summary of Remedial Design

This Operations and Maintenance (O&M) Plan was created as a guide for operating, monitoring and maintaining soil vapor extraction (SVE) equipment and vapor well plumbing installed at Camp Stanley Storage Activity (CSSA) in Boerne, Texas.  Two SVE systems were installed to address Area of Concern (AOC)-65, to remediate soil, fractured rock and groundwater contamination underneath and around Building 90. 

SVE is the forced evacuation of soil gas from the subsurface using vacuum equipment.  Vacuum blowers connected to vapor extraction wells (VEW) with pipe are typically used to evacuate volatile organic compounds (VOC), water vapor, and any air from the subsurface.  Contaminated soil gas as well as VOC dissolved in groundwater can be removed using SVE, thereby either remediating contamination or reducing its continued migration.

In 2002, Parsons Infrastructure and Technology Inc. (Parsons) installed seven VEWs on the west side of Building 90 and 12 VEWs beneath Building 90 along with the associated piping and equipment comprising the SVE systems.  Two regenerative vacuum blowers were installed and piped to a vessel of granular activated carbon (GAC), designed to remove all VOC emissions prior to discharge to the atmosphere. 

The objective of operating these systems is to enable removal of VOC vapor to promote remediation and reduce migration of contaminants in the groundwater.  The objective of continued monitoring activities is to gather additional data to allow an evaluation and optimization of the systems’ performance.

Although SVE systems are relatively simple, routine monitoring and maintenance of the SVE system is required to keep it operating at its optimum condition.  If significant problems are encountered with the operation of the system, the CSSA Environmental Officer, Mr. Brian Murphy at (210) 698-5208 should be notified so repairs can be initiated and coordinated.  Alternatively, contact the Parsons Project Manager, Mr. Brian Vanderglas at (512) 719-6000, or the Parsons Onsite Manager, Mr. Kyle Caskey at (210) 336-1164.

A layout drawing and a schematic of the SVE systems are provided in Sections 2 and 3 of this document.  In addition, a chronology of activities and investigations performed at AOC-65 is provided in the report Area of Concern 65 Interim Removal Action, Parsons Infrastructure and Technology Group, Austin, Texas, August, 2003 (Parsons 2003a) and the Draft Interim Treatability Study Report, Parsons Infrastructure and Technology Group, Austin, Texas, 2003 (Parsons 2003b).  These documents can both be found in the CSSA Environmental Encyclopedia (AOC-65 Links).

Section 2 - Site Conditions

2.1 Background

Chlorinated solvents, which are VOCs, were used in Building 90 cleaning processes for more than 30 years.  Chlorinated solvent usage was eliminated by pollution prevention initialization that replaced the process with a citrus-based cleaning solvent in 1995.

VOCs were first detected at concentrations above drinking water standards in a CSSA potable well water in 1991.  Groundwater samples collected from the monitoring wells installed at AOC-65 and off-post wells have contained VOCs also.

This prompted investigations of the probable source areas of contamination.  Source characterization of the Building 90 vicinity, (AOC-65), included a 2001 survey of 319 soil gas samples collected and analyzed for chlorinated and aromatic organics around and inside of Building 90.  Perchloroethene (PCE), trichloroethene (TCE), cis-1,2-dichloroethene (DCE) and trans-1,2-DCE were detected.  The occurrence of these chlorinated hydrocarbons has implicated Building 90 and its historical processes as the likely source of contaminants encountered in groundwater.  Furthermore, the detection of the TCE and DCE indicate that natural degradation of PCE is occurring in the subsurface. 

The soil gas survey was followed by 14 soil borings and numerous groundwater samples collected in and around Building 90 and from monitoring wells and piezometers installed in the vicinity.  The final Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI) report for AOC-65 was completed in September 2002 (Parsons, 2002b).  An interim removal action was also completed in 2002 included excavation of contaminated soils underlying the pavement and ditch on the west side of the building.

SVE pilot testing was performed at AOC-65 to evaluate removal of VOC contamination from vadose soils and groundwater.  SVE was demonstrated to be an effective method for source removal in surface formations at CSSA during a pilot and treatability study at Solid Waste Management Unit (SWMU) B-3.  This SVE system at AOC-65 was constructed and installed in late 2002 followed by completion of startup and initial testing in early 2003.  The primary objectives of this SVE system are to remove VOC contaminants from the soils, fractured limestone, and groundwater around AOC-65 (both subslab and surrounding Building 90) or at a minimum to stop the migration of contaminants. 

2.2  Site Delineation

Based on the results of the site investigation and recent groundwater results from the Westbay study report (Parsons 2003c), the area around AOC-65 that could be successfully treated for VOCs appears to extend immediately around Building 90 in the apparent down gradient direction to the west/southwest.  The total depth of VOC contamination has been encountered at levels above the Safe Drinking Water Act Maximum Contaminant Levels (MCLs) in groundwater intervals measured as deep as 300 feet below grade.  The total volume of the treatment area is unknown.  The locations of the AOC-65 system SVE wells are shown on Figure 2.1.

2.3  Air Emissions

The Texas Clean Air Act requires a permit to emit any pollutants to the atmosphere.  The Act is codified in 30 Texas Administrative Code (TAC) Chapter 116, “Control of Air Pollutants By Permits for New Construction or Modification”.  SVE systems remove contaminants by negative pressure while replenishing oxygen to microorganisms within soils; which, if soil gas is removed to accomplish the oxygenation of contaminated soils, could result in the emission of VOC to the atmosphere.  Generally, most soil gas removal systems involve very low air emissions rates.  Consequently the systems are generally exempted, under Permit By Rule §106.533, (formerly Standard Exemption 68), as outlined in 30 TAC Chapter 106 Subchapter X.

Rule §106.533 is applicable to “Equipment used to reclaim or destroy chemicals removed from contaminated materials for the purpose of a remedial action”.  Its provisions allow air emissions from treatment of groundwater and soils contaminated with petroleum compounds and chemicals other than petroleum products.  The emission of chemicals other than petroleum products must also be compliant with the limitations of the Facilities (Emission and Distance Limitations) rule §106.262(2), (3) and (4).  “New or increased emissions, including fugitives, of chemicals shall not be emitted in a quantity greater than 5 tons per year (tpy) nor in a quantity greater than E as determined using the equation E=L/K” where K is a parameter corresponding to distance to the nearest receptor and where L (Limit Value) is an emission limit of concentration provided for specific chemicals in Table 262 of §106.262.  The maximum emission on an hourly basis of any chemical having an L value in Table 262 is determined by the equation E=L/K.  The emission of any chemical not having an L value in Table 262 is one pound per hour (lb/hr), with or without abatement devices.  These limitations are applicable only to on-site remediation. 

An emissions permit is required since the system could emit air pollutants to the atmosphere.  However, based on the contaminant levels detected in soils and the expected flowrates, the site qualifies for a Permit By Rule exemption.  Nevertheless, a GAC adsorber was installed to ensure that contaminant levels in exhaust emissions would not exceed health-based standards during operation of the blowers or add additional VOCs to the environment. 

Figure 2.1:  AOC-65 SVE System Layout

An emissions limit formula in 30 TAC Chapter 106 Subchapter K, rule §106.262 (formerly Standard Exemption 118), Section (c), is used to determine maximum allowable emissions rates for chemicals other than petroleum fuels.  Part 68(e) provides technical conditions to be met when abatement is required to meet the specific chemical emission limit.  The calculated emissions rates for chemicals of concern at this site are presented in the Permit By Rule application prepared for these SVE systems at AOC-65 in August 2002 (Parsons 2002a).  The maximum allowable emission rate is 6 lb/hr (5 tpy) for PCE and 1 lb/hr (4.4 tpy) for cis-1,2-DCE, the two most common contaminants found in AOC-65. 

Emission samples collected as part of the initial system startup, and contaminant levels in emissions were significantly below the allowable levels.  The maximum PCE emission rate measured during initial system startup was 0.08 lb/hr (subslab) and 0.02 lb/hr (exterior), which equate to 0.07 and 0.0175 tpy, respectively.  Emission samples will continue to be collected and tested as part of preventive measures for contaminants of concern during routine operations, thereby providing periodic monitoring of contaminant levels in the system exhaust.  If the data indicate that contaminant levels in the exhaust from the SVE exceed applicable criteria, then the exemption, GAC adsorber operation as well as other practices will be re-evaluated.

Section 3 - System Description

An overall schematic of the SVE systems showing the VEWs and the associated equipment is provided in Figure 3.1.  Specifications of the major equipment for both the subslab and exterior SVE systems and other pertinent information are provided in Table 3.1.

Table 3.1
SVE Equipment Specifications

Figure 3.1 - Blower System Instrumentation Schematic

3.1  Vacuum System and Appurtenances

3.1.1  Vacuum Blowers

The main component of the SVE system is the device producing the vacuum.  The two SVE systems at AOC-65 use regenerative blowers mounted on square steel tubing anchored to the loading dock of Building 90.  Rubber grommets underneath the blower dampen vibrations.  A plan view of the blower area is shown on Figure 3.2.

Two blowers were installed, one existing blower salvaged from the former SWMU B-3 SVE treatability study and one new blower.  The existing blower, a GAST R6 Series Regenair® blower, which was used periodically at the SWMU B-3 site for approximately three years, was installed at AOC-65 to vent the subslab VEWs.  A new regenerative blower, a GAST Regenair® R6 Series unit was procured to produce the vacuum for the seven VEWs installed outside or exterior to Building 90.  The two R6 Series blowers share the same electrical requirements, and are similar in size and components (gauges, filters, plumbing, etc.).  The R6 Series blowers can maintain a vacuum of about 55 in. to 70 in. H₂O at the blower inlet depending on the flowrate. 

Motor disconnects, which are used for stopping and starting the units, are mounted on west wall of building.  Blowers are installed on individual circuits so they operate independently of one another. 

The blowers are relatively maintenance free and should not require any mechanical maintenance during the operational period.  Both the blower and motor have sealed bearings that do not require periodic lubrication.

Table 3.1 shows the blowers’ rated flow rates in actual cfm and vacuum in inches of water column (in. H₂O).  The blower system includes an inlet air filter and several valves and monitoring gauges, which will be described later in this section.  Blower performance curves and other blower information are provided in Appendix A, Manufacturers’ Equipment Information.

3.1.2  Moisture Separators

Two 40-gallon moisture separating knockout tanks were installed between the VEWs and each of the blower inlets.  Each knockout tank separates any condensate from the vapor recovered from the VEWs.  One separator is installed on each of the two systems.  The tanks are piped in parallel with suction provided by the manifolded VEWs and the discharge leading directly into the SVE blowers.  Tanks have a floating ball valve that ties into a vacuum relief valve (VRV), which automatically stops VEW evacuation by providing fresh air to the blower on high liquid level in the moisture separator.  A high-level float switch shuts down the vacuum blower associated with that knockout tank in the event excess liquid accumulates in the separator.  This seemingly redundant instrumentation protects the blowers, minimizes power consumption and alerts operators to a high liquid level in the moisture separators.

Figure 3.2 - Blower Area Plan and Section

Condensate accumulation in the moisture separators should not normally be of concern.  However, during the cooler months of the year, weather systems with cooler ambient air, can result in the ambient temperature being considerably below that of the soil vapor.  Since the soil vapor has a relative humidity of essentially 100 percent, condensate can readily fall out of the vapor and collect in the separator.  This could occur whenever the ambient air temperature is lower than the dew point of the soil vapor.

3.1.3  Blower Inlet Filter

To prevent damage caused by particles entering the blowers, an 8” diameter inlet filter with 2.5” diameter pipe connections is installed in-line upstream of each blower.  The pressure (or vacuum) drop across a clean filter is approximately 2 in. H₂O at 200 cfm.  The filters will slowly accumulate particles.  Once the pressure drop across a filter is greater than 6 in. H₂O, the filter element will need to be replaced with a new element.

3.2  Emissions Control

3.2.1  Recovered Vapor Treatment (Granular Activated Carbon Adsorption Unit)

Air emissions are controlled by a Waterlink/Barnebey Sutcliffe V-1M Vapor Phase GAC Adsorber with 16” manway on top for removal and refill of GAC.  The adsorber vessel captures any VOCs discharging from both blowers.  The vessel is movable by forklift but can be emptied and recharged in place.  The vessel was installed on the loading dock directly adjacent to the two blowers. 

Sampling ports on the inlet and the discharge piping of the GAC vessel allow sampling of the air stream into and out of the GAC unit to assure VOCs do not break through.  The interval between GAC recharge is estimated at more than one year, depending on quantity of VOC recovered and the operational continuity and usage time of the SVE systems.  Recharge intervals will be estimated based on vapor concentrations and flowrates over the operating life of the system. 

3.2.2  Recovered Liquid Treatment

Routine recovery of free liquid is not expected from the moisture separators.  Only on the rare occasions when the ambient air temperature is below the dew point of the VEW vapor is there a chance of liquid accumulation.  During these periods, if free liquid does accumulate, it will be collected, transported and treated at the GAC unit for Well 16.

Testing of accumulated liquid is not required since sampling and analysis was already done during initial startup at which time the VOC concentrations measured would not have resulted in a classification as hazardous waste. 

3.3  Monitoring and Control Equipment

3.3.1  Vacuum Gauges

The SVE system is equipped with gauges and a flow velocity measurement port at each well.  Gauges were also installed on the blower units to allow monitoring of operational conditions.  Monitoring will be done in accordance with the schedules and checklists provided in Appendix B.

3.3.2  Flow Control Equipment

Manually operated ball or gate valves were installed in the piping to each VEW to serve as flow control valves (FCVs).  This allows the individual flow rate from each VEW to be manually balanced.  Initially, the FCVs were set in the fully open position to maximize air flow out of the VEWs.  Air flows for the subslab VEWs are set in open position for all VEWs.  Balancing flows from the subslab can only be accomplished by taking selective VEWs off-line, which must be done inside the building. 

Attainable flowrates were lower than expected for the exterior SVE system due to excessive friction losses in the SVE piping network.  To balance the flowrates, some of the FCVs to the higher flow VEWs were partially closed.  The optimal flow settings were established during the final site visit on July 30, 2003 for the exterior VEW system.  FCVs should probably remain 100 percent open until piping restrictions are reduced or some of the VEWs are selectively taken off line.  However, if adjustment is desired to balance the flows from the exterior VEWs, then the FCVs are the proper tool to achieve that objective.

Combination flow measurement and sample collection ports, which consist of brass bushings threaded into the galvanized piping, were installed in line to allow direct measurement of flows and sampling of soil gases.  Flow ports were installed at each wellhead and at the blowers.  These ports allow the insertion of a thermal anemometer for the measurement of vapor velocity, which can then be converted to estimate the flow of vapor out of each individual VEW.  However, the bushings should be plugged during normal system operation when measurements are not being taken.  These ports can also be used to take soil gas samples to obtain contaminant concentrations for estimating mass removal rates.

Section 4 - System Operation and Monitoring

4.1  System Start-up

The following items comprise a system start-up list:  

       

	Check that moisture separator(s) is not full;
	Open FCVs to extract from desired VEWs and close, if desired, any FCVs to VEWs not desired;
	Check condition and operation of equipment and repair or replace as needed;
	Adjust vacuum relief/bleed valve(s) to maximum vacuum allowed (generally 55 in. H2O) to protect blower(s) from mechanical damage; and
	Start-up blower(s) and adjust FCVs to balance flows from VEWs in service, as desired.

4.2  Operation and Monitoring

The primary operating activities include monthly and quarterly monitoring of system performance, and twice monthly monitoring of equipment operation.  Parsons will take measurements and data for the initial six months of operation under Task Order 0058.  Performance data will be used to determine system effectiveness for the Assessment Report while equipment data will be used as it is gathered to maintain equipment in good operating condition. 

The operation and monitoring work described in this section include:

1. Monthly determination of soil vapor/emissions at the seven SVE VEWs, both blowers, and the GAC adsorber;

2. Monthly monitoring of flow rates, and vacuum pressures in the individual VEW flow streams, and at the equipment;

3. Twice monthly drive-by system checks of the equipment and piping network to adjust, repair and replace components as needed to maintain the systems in good operating condition; and

4. Quarterly monitoring and data collection of individual well flows and air emissions from both systems.

These data will all be recorded on one of the two data collection sheets in Appendix A.

4.3   Performance Data

To monitor the performance of the blowers, the inlet vacuum, the outlet pressure, and outlet temperature will be monitored on each blower on a twice-monthly basis.  All measurements should be taken at the same time, while the system is running. (Note: Because the blowers are noisy, hearing protection may need to be worn when working around the blowers).

4.3.1  VEW, Exhaust Emissions and Soil Vapor 

Blowers and knockout pots will be monitored twice monthly.  Every other system check will correspond with the monthly monitoring effort, during which VEWs and equipment points will be checked for VOC, oxygen and carbon dioxide concentrations. 

4.3.2  Quarterly Data Collection 

Soil vapor samples and emission samples will be collected on a quarterly basis for off-site analyses to confirm trends and field measurements.  All such vapor samples (emissions and soil) will be tested for VOCs by Method TO-14.  The CSSA Quality Assurance Program Plan (QAPP) will be followed for sample collection, analysis, and data validation.  Samples will be collected at the beginning of O & M, after three months (Quarter 1), and after six months when the initial O&M period is complete (Quarter 2).

4.3.3  Flows and Pressures

During operation of the two systems, flows and vacuum pressures from each SVE VEW will be measured and recorded biweekly.  The FCVs will be adjusted to balance the flow as desired.  If maintaining flow from the critical VEWs (those with high VOC removal rates) is not possible in then Parsons will determine which VEWs should be shut off to maximize removals. 

4.4  Operation/Maintenance Monitoring

4.4.1  Twice Monthly and Monthly Monitoring Visits

Twice monthly system checks will be performed to assure that system operation is satisfactory.  A check of the systems includes visual inspection of the equipment and the piping network for cracks, separations, holes and other problems.  Each of the well-heads and pipe joints will also be inspected for leaks or weakness of structure.  Blower operation, filter cleanliness and VRV operation and lubrication will also be checked or be done.  Finally, these visits include assessment and management of any accumulated liquid in the moisture separators. 

4.4.2  Vent Well Air Flow Rate

The flow rate into each vent well is calculated using direct measurements of in-line air velocity and pipe size data.  Air velocity is measured by placing an anemometer into the air measurement port located on each vent well pipe.  The volumetric flowrate is calculated by multiplying the velocity obtained times the cross-sectional area of the pipe.  Flow data allow more accurate adjustment of the FCVs at each vent well to balance flows through the system. 

4.5   Monitoring Schedule

The following monitoring schedule is proposed for these systems.

Table 4.1
Monitoring Schedule

Section 5 - System Maintenance

Although the blower system installed is very low maintenance, periodic system checks are required to ensure proper operation and long life.  Recommended maintenance procedures and schedule are described below.  Manufacturers’ equipment information is presented in Appendix B.

5.1  Vacuum Blower, Piping and Instrumentation

5.1.1  Vacuum Blowers

Two blowers were installed, one existing and one new blower.  The existing blower was used periodically at SWMU B-3 for approximately three years.  The approximate operating life of a properly maintained blower may extend up to five years.  However, this maybe shortened should abrasive particles pass the filter element.

The blowers and motors are relatively low maintenance and may not require any maintenance during the operational period.  Both the blower and motor have sealed bearings that do not require periodic lubrication.

5.1.2  Piping

The different piping (or plumbing) materials used were selected both for durability and environmental resistance as well as ease of installation.  Only periodic visual inspection is required to make sure the network is intact, tight, and undamaged.  Damage to piping could occur due to landscaping, unloading activities or any other work activities in the area.

5.1.3  Blower Filter

Filter inspection must be performed with the system turned off.  Do not change the FCV settings before re-starting a blower unless a rebalancing of the VEWs is desired.

The filter elements should be checked monthly and replaced a minimum of every six months.  Typical filter element replacement intervals are estimated at three to six months depending on blower run time.

To remove the filter:

1. turn the system off by opening the disconnect,

2. loosen the three clamps or the wing nut on the filter top,

3. lift the metal top off the filter, and

4. lift the filter element from the metal housing. 

5. Reinstall new element by reversing order of disassembly.

The replaceable air filter element is manufactured by GAST Manufacturing, Inc. in Benton Harbor, MI (269) 926-6171.  Spare filter elements were not purchased.  However, replacement filter elements can be obtained directly from the manufacturer or from the supplier Southwestern Controls, San Antonio office, 210-613-2900 or Houston office at 713-777-2626 (replacement filter elements for both blowers are GAST Model AJ 135G).

5.2  Granular Activated Carbon Adsorption Unit

The GAC adsorber is a Waterlink/Barnebey Sutcliffe  V-1M Vapor Phase Adsorber with 16” manway on top for removal and fill of GAC.  The unit has no moving parts and does not require any routine maintenance other than replacement of GAC when spent.  Breakthrough of VOCs will indicate the GAC is spent, but this is strictly a function of blower flowrate and VOC concentration, or more precisely the mass quantity of VOC removed.  Periodic monitoring of inlet and outlet concentrations should provide an indication of when GAC will require replacement.  In general vapor phase adsorption is fairly efficient so a year or more would not be an excessive period between changeouts especially since removal rates are low and a 1000 lb of GAC is in place.  Nonetheless, GAC analysis is proposed after the initial six months of operation so that the required changeout frequency can be analytically estimated.

5.3  Maintenance Schedule

In general, SVE systems are very reliable when properly maintained.  Occasionally, however, a motor or blower will develop a problem.  If a blower fails to start, and an electrician verifies that power is available at the blower or starter, Parsons should be contacted to arrange for repairs.

Twice monthly inspections are recommended (see Section 4) for the blower systems.  During the initial operation, more frequent monitoring may be needed to ensure that any startup problems are quickly corrected.  See Appendix B data collection sheets for recording maintenance activities.

Section 6 - Reporting Requirements

At the end of the initial six months of operations and monitoring, Parsons will prepare a final Technology Evaluation Report.  This report will include analytical data from the quarterly sampling events, and is intended to compare the effectiveness of the subslab ventilation and exterior SVE systems with other potential or emerging and innovative cleanup technologies.  Recommendations and/or modifications that can be made to improve SVE efficiency at the site may be provided in this report. 

No State Agency reporting is required for this project.

Section 7 - Bibliography and References

Parsons 2003a.  Area of Concern 65 Interim Removal Action, Parsons Infrastructure and Technology Group, Austin, Texas, August, 2003.  

Parsons 2003b.  Draft Interim Treatability Study Report, Parsons Infrastructure and Technology Group, Austin, Texas, 2003  

Parsons 2003c.  Westbay Study Report, Parsons Infrastructure and Technology Group, Austin, Texas, 2003  

Parsons 2002a.  Area of Concern-65 Permit By Rule Application for Removal Action, Parsons Infrastructure and Technology Group, Austin, Texas, August 2002.  

Parsons 2002b.  Area of Concern-65 RCRA Facility Investigation Report, Parsons Infrastructure and Technology Group, Austin, Texas, September 2002.

Appendix A - Manufacturers’ Equipment information

Appendix B - Data Collection Sheets