by Lead-Based Paint - P2 InfoHouse by wangnianwu


									Headquarters Air Force Center for Environmental Excellence

                      4th Annual

     Air Force
Worldwide Pollution

    Conference and Exhibition
  The Feasibility of Demolition by Mechanical Grinding for
      Wood Buildings Impacted' by Lead-Based Paint
                      Michael F. Redfem, Chief, Environmental Flight
                                       37 CES/CEV
                              Lackland Air Force Base, Texas
                                      (210) 671-4843

                              Kirk D. Johnson, President
                        CCR Environmental Inc., San Antonio, Texas
                                    (800) 256-5001


Over the next few years Lackland Air Force Base will demolish approximately 844,000 sq. ft. of
non-historical and substandard World War I1 and Korean War era buildings and family housing
units'resulting in substantial amounts of construction and demolition (C & D) debris impacted by
lead-based paint (LBP). Pursuant to the Resource Conservation and Recovery Act (RCRA) as
amended by the Hazardous and Solid Waste Amendments of 1984 (HSWA) regulations
regarding proper characterization and disposal of hazardous waste, the Department of Defense
and the United States Air Force have in the past disposed of these materials as a hazardous waste.
Due to the character of C&D debris, these materials exhibit excess void areas (greater volume)
which has resulted in higher loading, transport and disposal costs than a denser material (less
volume). Additionally, the various sampling methodologies utilized to characterize the buildings
are at time ambiguous, controversial and significantly more expensive than the sampling required
to profile a homogeneous waste material.

Faced with the prospect of large quantities of C&D debris infused with lead fiom the demolition
of buildings impacted with LBP, Lackland AFB, together with Region 13 of the Texas Natural
Resource Conservation Commission (TNRCC) and two environmental consulting/contracting
firms (Olmos Construction, Inc. and CCR Environmental Inc.) formed a pollution prevention
partnership to develop unique equipment and a cost effective methodology to deal with the

Two "pilot" projects were designed to test the equipment and methodology developed. Primary
project objectives were to evaluate the human health and environmental effects of grinding the
lead-based paint impacted C&D debris and to volume reduce the debris to provide substantial
cost savings for the government as well as preservation of valuable landfill space. Secondary
objectives were to homogenize the debris thereby simplifying the sampling and providing an
acqwate characterization of the debris for proper disposal and to evaluate any recycling or reuse

        SESSION XI
       Session Chairpersons:
            Betty West
           CZifton Jester
          Galson Corporation


A key issue in the development of the grinding process was to assess the risk to human health
and the environment exhibited during the grinding process. Personnel involved in the demolition
and grinding activities were fitted with personal a r sampling devices to determine exposure
levels. Air samples were collected at various up wind and down wind positions to provide total
lead, total cadmium, total chromium and respirable particulate levels prior to and during the
grinding operations. Post-grinding bulk samples were collected to establish total lead, total
cadmium and total chromium levels in the C & D debris.


The United States Air Force demolished two similar vacant buildings at Lackland Air Fo:ce Base
during grinding activities for the first pilot study in November 1994 and three buildings for the
second’pilot study in May 1995. The structures were surveyed for asbestos and lead-based paint
prior to any site work. All asbestos-containing materials were removed and properly disposed
prior to demolition. Light fixtures and large plumbing fixtures were also removed prior to
demolition activities and the majority of the metal (flashing, vents, etc) was recycled.

All five buildings were nearly identical wood fiame structures on concrete slab foundations.
Exterior building materials consisted of: transite asbestos siding, wood framed windows and
doors, wood fascia and soffit and composition shingle roofs. Interior building materials
consisted of: concrete, vinyl floor tile, carpet, gypsum board and wood walls, and gypsum board
and suspended tile ceilings. Lead-based paint primarily impacted wood ti boards (window &
door frames, fascia) and soffit panels. Each building contained approximately 380 linear feet of
ti boards and 280 square feet of soffit. Laboratory analysis indicated pre-demolition total lead
levels ranged from 52 mg/Kg to 32,884 mgKg in the impacted building materials.

During the first pilot study, LBP components from one building were removed and stored for
later grinding while all LBP components were left in-place on the second building. All LBP
components were left in-place for the second pilot study. Following demolition, C & D debris
was transported, via lined and covered vehicles, to a site located immediately south on Lackland
Air Force Base and staged for the grinding procedures. Grinding was not conducted at the
building site due to close proximity of the Lackland Independent School District.


During the first pilot study, the grinding procedures were completed in three stages. Stage one
ground the LBP components removed from Building #8122. Stage two ground all the materials

from Building #8141(LBP components intact) and stage three ground the remaining material
fiom Building #8122 (all LBP components removed). Brush and tree limbs were processed
through the grinder between stages to reduce cross-contamination potential.

During both pilot projects, Olmos Construction Company of San Antonio, Texas, utilized a
trailer-mounted and modified Diamond Z PWG 1463 Tub Grinder to reduce the stockpiled C&D
debris to approximately 3/8 inch size particles. A total of approximately 900 cubic yards C&D
debris was thoroughly watered prior to grinding to reduce dust and particulates. A track loader
was utilized to load the stockpiled material into the grinder. The grinder tub was modified with
water jets to further reduce the emission of dust and particulates. The grinding procedures
reduced the 900 cubic yards of debris to approximately 225 cubic yards. Grinding procedures
were conducted over a three day period, although the grinder does have a capability of grinding
6,000 cubic yards per day under normal operating conditions.


All %r samples were collected utilizing Ametek Alpha-1 air sampling pumps calibrated to 4 liters
of air per minute, pre-weighed certified blank filters (specifically for metals), and 37mm, open
faced air sampling cassettes. Analytical methodologies include EPA 213.2 for total cadmium,
EPA 21 8.2 for total chromium, EPA 23’9.2for total lead and EPA 160.2 for respirable particles.

First Pilot Study: Comparable analysis of the a r samples collected during the first grinding
pilot study indicated field blanks, background samples and some air samples collected during the
grinding process exhibited chromium levels in excess of the recommended TNRCC Toxicology
and Risk Assessment (TARA) 30 minute ESL guideline levels for airborne chromium (0.1p/m3).
As it was unclear as to the cause of the levels of chromium, a limited background air sampling
project was recommended. The air sampling project was designed to provide general chromium
and respirable particles baseline levels for the second pilot grinding project.

Limited Air Sampling: Ar samples collected during the limited air sampling project confirmed
airborne chromium levels near the grinding site are at times above the TNRCC’s TARA 30
minute ESL for airborne contaminants. No air modeling studies have been conducted by federal,
state or local agencies to determine if background chromium levels in the San Antonio area
exceed the TNRCC TARA 30 minute ESL.

Second Pilot Study: A second grinding pilot project was designed to again provide a risk based
assessment of the grinding process. Air monitoring emphasized the testing of the airborne
respirable particulates and total metals (cadmium, chromium, and lead) prior to and following the
grinding process.

fialysis of all background air samples indicated the average airborne levels of respirable
particulates were 0.76 mg/m3. Analysis of all samples collected during the grinding projects


    indicated the average airborne levels of respirable particulates during grinding activities were 2.7
    mg/m3. The OSHA regulatory limit for levels of respirable particulates of wood dust is 5.00
    mg/m3as found in 29 CFR Sec. 1910.1000

    Analysis of all background air samples indicated the average airborne levels of lead were below
    detection limits. Analysis of all samples collected during the grinding projects indicated the
    average airborne levels of lead during grinding activities were 0.123 ug/m3. The TNRCC’s
    TAR4 30 minute ESL for airborne contaminants for lead is 1.00 ug/m3 .

    Analysis of all background air samples indicated the average airborne levels of chromium were
    0.105 ug/m3. Analysis of all sampIes collected during the grinding projects indicated the average
    airborne levels of chromium during grinding activities were below detection limits. The
    TNRCC’sTARA 30 minute ESL for airborne contaminants for lead is 0.1 ug/m3.
    Analysis of all background air samples indicated the average airbome levels of cadmium were
    below detection limits. Analysis of all samples collected during the grinding projects indicattd
    the average airborne levels of cadmium during grinding activities were below detection limits.
    The TNRCC’sTARA 30 minute ESL for airborne contaminants for lead is 0.1 ug/m3.

                  Average 1st       Average 2nd        Average           Regulatoty
                   Grinding          Grinding         Background           Limits

                                GRAPH OF AIR SAMPLING RESULTS


Samples of the ground material were analyzed for total lead, total chromium, and total cadmium
content utilizing EPA testing methodology 6010. Samples which contained total levels of lead,
chromium or c a d " above 30mgKg were tested for the appropriate metal utilizing EPA 6010
TCLP methodology.

First Pilot Study: +alysis of stage one grinding samples (LBP components only) indicated
total lead of 888.0 mgKg, total chromium of 37.0 mgKg, and total cadmium of 6.0 mgKg
while TCLP levels were 0.10 mgfl, cO.1 mg/l and.CO.1 mg/l respectively. Analysis of stage two
grinding samples (entire building with LBP intact) indicated total lead of 850.0 mg/Kg, total
chromium of 13.0 mgKg, and total cadmium of 5.5 mgKg while TCLP levels were 0.14 mg/l,
<0.1 mg/l and CO.1 mg/l respectively. Analysis of stage three grinding samples (entire building
with no LBP) indicated total lead of 96.5 mgKg, total chromium of 15.0 mgKg, and total
cadmium of 2.5 mg/Kg while TCLP levels were all cO.1 mg/l. Based on these sample analysis
results, the TNRCC, Industrial and Hazardous Waste Division, Waste Evaluation Section in
Austin approved the material for disposal as a non-hazardous special waste.

Second Pilot Study: Analysis of the samples collected indicated total lead levels ranged from
188mg/Kg to 1320 mgKg, total chromium levels ranged from 6.2 mgKg to 39.0 m a g ; and total
cadmium levels ranged fiom 4 . 0 mgKg to 4.5 m a g . Bulk samples above 30mgKg were tested
for the appropriate TCLP metal (6 TCLP lead and 2 TCLP chromium). Sample analysis for TCLP
lead ranged fiom 0.09 mgA to 0.22 mgfl and sample analysis for TCLP chromium were all below
detection limits. Based on total levels of c a d " , TCLP analysis for cadmium w s not required.
Based on these sample analysis results, the TNRCC approved the material for disposal as a non-
hazardous special waste.




                                                                                    m TCLP Cr
         2                                                                          OTCLP Cd

                 Average 1st         Average 2nd         Class II Non-Haz
  --              Grinding            Grinding            Landfill Limits



Based on laboratory analysis of air samples, levels of airborne respirable particles, lead, c a d ” ,
and chromium do not appear to be adversely affected by the grinding operations.

Based on laboratory analysis of bulk samples during both pilot studies, levels of lead, cadmium,
and chromium are relatively consistent and indicate the grinding operations result in a
homogeneous distribution of debris. Results of the first pilot study shows comparative analysis
of the grinding of LBP components only versus grinding entire buildings with LBP in-place
indicates there is little impact on sample analytical results. Comparison of pre-demolition
sample analysis (lead ranging fiom 52 m a g to 32,884 mg/Kg) to post-grinding sample analysis
(lead ranging from 375 mgKg to 850 mgKg) indicates grinding appears to allow for more
reliable waste stream determinations. In all cases the analysis of the bulk samples indicated
TCLP levels of lead, chromium and cadmium were well below both EPA and TNRCC levels for
classification as a hazardous waste.

Both primary objectives of the study were met. The effects on human health and the
environment appear to be minimal and the operation has been proven to significantly reduce the
volume of material to be landfilled. This translates to a substantial preservation of valuable
landfill space and significantly lower loading, transportation, and disposal charges. Cost
comparison of this pilot study and previous demolition operations indicates the grinding process
results in a substantial cost savings to the traditional knock-down haul-off demolition
technologies utilized by the Air Force. The attached cost comparison shows a savings of over
$2.50 per square foot utilizing the mechanical grinding method. Similar cost comparisons
utilizing various building types have been conducted at Lackland with similar results. One of the
secondary objectives was met by homogenizing the debris thereby providing an accurate
characterization of the waste. The other secondary objective of evaluating recycling and reuse
opportunities is under evaluation. The relatively void free debris does provide the landfill
operators with a material to fill void spaces created by disposal of traditional unground C&D

                                          COST COMPARISON

             ITEM                                                                         PROP0SF.D METHOD
                                                                  om          CQSI        om         m
 DOORS, WINDOWS, TRIM             LF               $2.25              1900    $4,275.00          0        $0.00
 FASCIA, SOFFITS                  SF               $2.25              1400    $3,150.00          0        $0.00
 PRE DEMO SURVEY &                LUMP         $2,300.00                 1    $2,300.00          1    $2,300.00
  ANALYSIS FOR LBP                SUM
 KNOCKDOWN WOOD                   SF               $0.50              5000    $2,500.00      5000     $2,500.00
 GFUNDING OF WOOD                 CY               $2.00                0         $0.00        900    $1,800.00
 LOADING                          CY               $0.50               900     $450.00         225     $1 12.50
 WOOD DEBRIS                      CY/MILE          $0.15               885    $1,327.50          0        $0.00
 HAZARDOUS WASTE DEBRIS CY/MILE                    $0.15                15     $733.50           0        $0.00
   (326 Miles)
 SPECIAL WASTE (CLASS 2)         CY/MILE           $0.15                0         $0.00        225     $337.50
 WOODDEBRIS          '            CY               $8.00               885    $7,080.00          0       $0.00
 HAZARDOUS WASTE                 CY              $276.00                15    $4,140.00          0       $0.00
 SPECIAL WASTE (CLASS 2)          CY              $11.00                0         $0.00        225    $2,475.00
 INDUSTRIAL HYGIENIST            DAYS            $375.00                2      $750.00          2      $750.00
 LABORATORY ANALYSIS:            EA              $195.00                2      $390.00           8    $1,560.00
 LABORATORY ANALYSIS:            EA              $105.00                10    $1,050.00         16    $1,680.00
 REPORT PREPARATION              EA                                           $1,000.00               $2,300.00

        TOTAL DEMOLITION AND LEAD                                            $29,146.00              $15,815.00

            Savings to the Government (per building) = $13,331.00

Cost comparison for 5-1,000 square foot single-story wood frame buildings
Costs do not include demolition of concrete or any site restoration


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