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PUBLIC HEALTH ASSESSMENT

HIGHWAY 71/72 REFINERY
BOSSIER CITY, BOSSIER PARISH, LOUISIANA


FIGURES


Figure 1. General Location Map


Figure 2. Approximate Refinery Boundary


Figure 3. Location of Past Refinery Features


Figure 4. Locations of Highest Concentrations of Metals


Figure 5. Locations of Highest Concentrations of Soil Gas


Figure 6. Locations of Highest Concentrations of PAHs and other Semi-Volatiles in Surface Soil


APPENDICES

Appendix A - Demographics, Land Use and Natural Resources

Demographics

The population number of those residing on the Highway 71/72 Refinery Site is 2,985. Approximately, 850 residents are women between the ages of 15 and 44, and 309 are children 6years of age or younger who reside on the site.

Land Use

The Highway 71/72 Refinery Site is zoned for residential and commercial use. Several apartment complexes and subdivisions have been built on the site. Commercial establishments on-site include restaurants, hotels, and retailers. No industries or commercial agricultural activities were noted on-site.

Natural Resources Use

The Highway 71/72 Refinery site residents use municipal water as their drinking water source. No known private wells exist on site. The site lies on a flat river valley with a less than a 1% slope towards the Red River. The annual average precipitation is 48 inches, and there is no recreational surface water on the site. The Red River aquifer lies below the site with a distance of 12 - 14 feet between the ground surface at the highest level of the aquifer. There are no continuous layers of soil beneath the site. Rather, there are alternating areas of clay, sandy clay, and sandy silt.


Appendix B - Technical Review of Air Data for Highway 71/72 Refinery Site

DATA SUMMARY AND HEALTH REVIEW:

Indoor Air, Soil Gas, and Ambient Air
Highway 71/72 Refinery Site
Bossier City, Louisiana

PURPOSE AND STATEMENT OF ISSUES:

The Agency for Toxic Substances and Disease Registry (ATSDR) and the Louisiana Department ofHealth & Hospitals/Office of Public Health/Section of Environmental Epidemiology & Toxicology(LDHH/OPH/SEET) have conducted a review of the air data collected at the Highway 71/72Refinery site in Bossier City, Louisiana. The purpose of this review was to:

  1. Attempt to determine if indoor air contaminants that may be associated with the sitepose a threat to the health of residents and/or building occupants such as workers,guests, etc., and

  2. Identify if environmental data gaps exist that limit the ability of the health agenciesin assessing the health impact of the site.

DATA AND INFORMATION REVIEWED:

To date, the following indoor air, ambient air, and soil gas monitoring/sampling investigations have been conducted:

  1. Report of Indoor Air Quality Monitoring and Sampling Services at the Residence Inn, 1001Gould Drive, Bossier City, LA--For Marriott Corporation. Law Engineering, March 6,1990.

  2. Indoor Air Monitoring Report, Alexis Park Apartment Complex, Bossier City, LA (includesVolumes II and III, Appendices A-H), August 15, 1990, ERM-Southwest.

  3. Bossier City Indoor Air Data, ENTEK, 1990-91.

  4. Indoor Air Data, ALCHEM, January 30, 1990.

  5. Bossier City Indoor Air Data Sheets (Carriage Square and Alexis Park data), LDEQ AirToxics Lab, 1993.

  6. Final Indoor Air Monitoring and Analysis Supplement to the Site Investigation Work Plan,Former Arkansas Oil Refinery Site, Bossier City, LA. Law Environmental, Inc., January1994.

  7. Indoor Air Monitoring and Analysis Report, Former Arkansas Fuel Oil Refinery Site,Bossier City, LA. Law Environmental, Inc., May 1994.

  8. Remedial Investigation Summary Report, ERM-Southwest, Inc., June 7, 1995.

  9. Volume VIII, Soil Gas Survey Results Remedial Investigation, Former Arkansas Fuel OilRefinery Site, Bossier City, LA. ERM-Southwest, Inc., June 7, 1995.

  10. Resource Document, Volume 2, Appendix 5, July 1988.

A summary of the investigations and data used in this review, along with concerns with thelimitations of each investigation, is found in this report. If additional clarification information, or data become available, this review will be amended accordingly.

FINDINGS:

From a public health perspective, the overall conclusions of this review indicate that:

  1. Benzene concentrations found in some indoor samples from 1990-1994 are at levels ofpublic health concern.

  2. Existing data gaps make it difficult to determine if contaminants detected indoors are site-related.

  3. Some contaminants, such as sulfur compounds and vinyl chloride commonly associated withoil and refinery activities that could be of health concern were not consistently analyzed insoil gas, groundwater, or indoor air samples. Therefore, the health agencies do not considerthe site contaminants to be adequately characterized.

  4. Some of the sampling investigation analyses was conducted with instruments with analyticaldetection limits higher than levels of public health concern; therefore, we cannot determineif exposure is occurring at levels of health concern.

  5. The source of odors which have been reported by residents since the mid 1980's has not bedetermined and the contaminants responsible for the odors have not been identified.

  6. The duration of most of the indoor air sample collection (FID, Tedlar bag, dosimeter, andcharcoal and colorimetric tubes) efforts was not long enough or consistent enough todetermine if the results are representative of daily exposures.

  7. The sampling methods used for methane monitoring cannot determine if indoor methanelevels fluctuate up to possible explosive levels.

  8. The levels of methane reported in soil gas sampling are a potential explosion hazard duringfuture earthmoving activities that may occur during construction and utility line work. Thelevels of other volatile organic compounds such as benzene are also elevated and are causefor health concern during subsurface soil excavation.

RECOMMENDATIONS:
Based on this review, it is recommended that:

  1. The site soil gas be fully characterized for contaminants -- especially for contaminantsassociated with refinery and petroleum sites. Analysis of soil gas should include prioritypollutant volatile organic compounds, organic sulfur compounds, and inorganic volatilesulfur compounds.

  2. Depending on the results of Recommendation (1), indoor air sampling for targeted soil gas contaminants may be necessary.

  3. Methane levels should be monitored in selected residences and buildings over a continuoustime period (several months) to ensure that a fire and explosion condition is not a possibility.

  4. Workers involved in activities dealing with contaminated on-site subsurface soil andgroundwater should be protected from exposure to contaminants. Levels of volatile organiccompounds such as methane, benzene, and chlorinated hydrocarbons should be monitored toprevent adverse health effects to workers and residents and ensure an explosion hazard does not exist.

DATA REVIEWED

A description of the sampling conducted, the analytical results, and the limitations of eachmonitoring event are provided as follows:

(1) Indoor Air Quality Monitoring and Sampling Services at the Residence Inn, 3/6/90
This investigation was initiated in response to complaints of odors by occupants and/or employees. Indoor air monitoring and groundwater sampling were conducted in February 1990. Based on areasof odor complaints, 31 residential units were screened for total volatile organics using a portableflame ionization detector (FID). Screening included living space air and suspected areas of gasentry (floor drains, plumbing, etc.). Screening values from non-detect (ND) to greater than 1,000ppm (parts per million, methane equivalents) existed in the living space air, and from ND to 900ppm in areas of suspected gas entry. Colorimetric indicator tube screening for benzene, toluene, andxylene was also conducted in units with the highest FID readings. In 3 of the units, air sampling (1-hour sample period) was conducted and analyzed for BTEX and phenol. Two of these 3 units hadthe highest FID readings in the living space, the third unit had non-detectable FID readings in theliving space. An air sample was also collected outdoors. See Table 1 for a summary of samplingresults.

FID headspace air screening were conducted on the headspace air of 3 monitoring wells. One headspace air sample ( hour sample period) was collected from 1 monitoring well and analyzed for BTEX. Water samples were also collected from these wells and analyzed for volatile and semi-volatile organic compounds. Results are summarized in Table 2.


Table 1.

February 1990 Indoor Air Investigation-- Residence Inn Air Sampling/Monitoring Summary
Contaminant
(ppm)
Location
Unit
311
Unit
314
Unit
612
Deck Outside Building 3 MW B-1
FID 8 - 100 3 - >1,000 2.5-10 NA >1,000
Benzene 0.01 0.08 ND ND ND
Ethyl-benzene 0.01 ND ND ND ND
Toluene 0.03 ND ND ND ND
Xylene 0.01 ND trace* ND ND
Petrol Dist trace* NA 0.1 NA 0.7
Phenol NA NA NA NA NA
* Detectable but below quantifiable amount.
Note: Indoor units: 1-hour sampling period
         Outdoor and MW: -hour sampling period


Table 2.

February 1990 Indoor Air Investigation--Residence Inn Monitoring Well Water Summary
Contaminant (ppb) Location
B-1 B-2 B-3
Naphthalene ND 660 ND
2-methyl-naphthalene ND 340 ND
Benzene 61 310 <5
Ethylbenzene <5 220 <5
Toluene <5 100 <5
Xylenes <5 160 <5
4-methyl-2-pentanone 31 20 23

Limitations of the data include:

  1. Levels of contaminants found in the indoor air are not high enough to result inodor complaints.

  2. Indoor air sampling was conducted for a one-hour period in three of the 31 unitswhere there had been complaints of odors, but this limited sampling time doesnot provide representative air sampling results for persons residing in the units.

  3. Sampling method detection limits are above ATSDR health comparison values.

  4. Except for monitoring well sampling, analysis was limited to BTEX and phenol. In order to evaluate the odor, sampling with lower detection limits and for VOCsand odor-causing compounds (sulfur compounds) is necessary. It is alsonecessary to consider other sources of the odor other than the groundwater (i.e.,tar seeps).

(2) Indoor Air Monitoring Report, Alexis Park Apartment Complex, Bossier City,Louisiana--including Volumes II and III, Appendices A-H. August 15, 1990, ERM-Southwest

This investigation was initiated in January, 1990, as the result of both odor complaints in several ofthe apartment units, and initial testing by the LDEQ and OXY Inc.. The purpose of thisinvestigation was to monitor the total hydrocarbon vapor concentration, determine the vaporcomposition, and provide a database for assessment of health risks from the vapors, if any.

As part of the weekly and/or monthly air monitoring program performed in all of the apartmentbuildings, up to 10,000 air monitoring readings were taken with a flame ionization detector (FID). This monitoring was conducted in up to 6 locations in each apartment, including breathing zones invarious rooms, underneath sinks, and inside cabinets. To better characterize the FID readings inbuildings 5,9,12,13, and 19, 28 Tedlar® bag air samples, 33 charcoal samples, and 16 dosimetersamples were collected. Tedlar® bag samples were collected over a five-minute period, post-sampling pump, and analyzed for benzene and C1 - C5 hydrocarbons. If analysis indicatedcontaminants of hydrocarbons of C6 and greater, the sample was reanalyzed for hydrocarbons usinga GC/MS. Charcoal tube samples were collected for 3 hours and dosimeter samples were exposedfrom 6 to 10 hours. Both sample types were analyzed for BTEX and total hydrocarbons.

Methane was detected in all Tedlar® bag samples from April 9- June 10, 1990. Levels ranged from26 - 4147 ppm. All of these samples were collected under sinks and inside cabinets. Analysis ofsamples for total hydrocarbons indicates an average, 95% confidence level (CL), range of from 0.3to 440.6 ppm under all kitchen sinks monitored. The highest total hydrocarbon value was 9,295ppm. In the living space, the 95% CL ranged from 0.3 to 221.1 ppm; the highest total hydrocarbonvalue was 2919.5 ppm.

These methane concentration ranges did not include data collected several feet underneath building5 on February 5, 1990. Four samples were collected and analyzed for C1-C6 hydrocarbons(GC/MS). Methane levels underneath apartment 501 were 30,000 ppm and 40,000 ppm, andunderneath apartment 505 were 160,000 ppm and 230,000 ppm.

Results of the Tedlar® bag and the charcoal tube analysis have a detection limit for benzene of 0.1ppm. The dosimeter analysis had a detection limit of 0.1 to 0.2 ppm. These values are above theATSDR screening value. Therefore, we cannot rule out benzene as a contaminant of health concern.

According to the report, when conducting initial gas chromatograph (GC) analysis of the Tedlar®bag samples on the GC, laboratory standards were only routinely run for calibration of methanethrough hexane (C1- C6) analysis. For the March through July sampling, a benzene standard wasonly analyzed once. The analytical results indicate that benzene was not detected (detection limit of0.1 ppm). In addition, it appears that when the samples were rerun, using GC/MS instrumentation,more than a month had passed since the samples had been collected. Volatile and semivolatilesamples collected in Tedlar® bags diffuse out of the bag over time. Other contaminants may diffuseinto the bag. As a result, analysis should occur as quickly as possible after the samples are collected. The results of 8/90 VOC GC/MS analysis for Apartment 1905 are displayed in Table 3.


Table 3.

Alexis Apartment #1905 Indoor Air Results Sampling Tedlar®(Approx. 7/19/90 sampling, 8/1 or 14/90 analysis)--VOCs*
Contaminant (ppm) Location
Under Kitchen Sink, Apt 1905
#90200-04
Apt 1905, Under Kitchen Sink
#90199-04
Apt 1905, under Kitchen Sink
#90197
Methane 2,348 1,053 1,158
Chloromethane <0.01 0.60 <0.01
Vinyl Chloride <0.01 0.11 <0.01
Methylene Chloride ND** ND 0.61
Chloroform ND ND 0.06
1,1-dichloroethane ND 0.01 ND
1,2-dichloropropane <0.01 <0.01 <0.01
1,1,2-trichloroethane 0.07 ND ND
Benzene 0.11 0.09 0.02
Toluene 0.03 0.05 0.02
Ethyl benzene 0.02 0.02 <0.01
Acetone 168.93 19.06 0.78
Carbon disulfide ND 0.29 0.43
Vinyl Acetate 0.35 0.66 0.75
2-hexanone ND ND 0.01
* = Laboratory qualifies data with "lab reported
data to be used for qualitative purposes only"
** ND = not detected

Results of the January through July, 1990, charcoal and dosimeter badge sampling (Appendix F ofthe Indoor Air Monitoring Report) are summarized in Table 4. Charcoal samples, totaling 33, werecollected; analyses for BTEX were performed on 3 of the samples; BTX on 10; and benzene on 22. Hydrocarbons (total or light/heavy) were analyzed in 13 of the above samples. Approximately 17dosimeter samples were collected: 10 were analyzed for BTX, 5 for benzene and total hydrocarbons,and 2 for benzene only.


Table 4.

Alexis Park 1990 Charcoal Tube and Dosimeter Sampling Results
Benzene
(ppm)
Toluene
(ppm)
Ethyl-Benzene
(ppm)
Xylene (ppm) Hydrocarbons*
<0.1-0.11** <0.1 <0.1 <0.1 T=5.8-28.8 ppm
TH=375-420 mg/m3
L = 233 mg/m3
* T and TH = total hydrocarbons (breakthrough to the back half of charcoal tube)
L = light hydrocarbons

** Only one sample found benzene above the 0.1 detection limit. Benzene levels may be low, as desorption/breakthrough may have occurred.


Limitations of the data

FID Monitoring:

Weekly or monthly monitoring for methane is not indicative of the possible peaklevels that may occur throughout the day. Methane monitors that monitorcontinuously should be installed to better determine if methane reaches explosivelevels.

Tedlar® Bag Sampling:

  1. Tedlar bag samples were collected by drawing the sample through a pump andthen into the bag. This can allow for contaminants in the pump to enter thesample bag.

  2. Samples were collected over a 5-minute period, and are considered grab samples. Although useful for characterizing which contaminants are present in the air,results are not likely to be representative of indoor air contaminantconcentrations.

  3. For GC/MS analysis, sample holding times appear to have been exceeded. Thisdata is not reflective of the possible contaminants and their concentrations in theapartment units.

  4. Benzene analysis should not be considered quantitative; in the initial GCanalysis, a benzene standard was only used once over a one month period; in theGC/MS analysis, sampling holding times were exceeded.

  5. Except for the GC/MS analysis in Apartment 1905, of the contaminantsanalyzed, none were found at levels that would cause odor complaints; therefore,the cause of the complaints has not been found.

  6. Analytical detection limits are above health-based screening levels, so a healthrisk evaluation cannot be completed (possibly can be completed for apt. 1905,but sample holding time makes the data very questionable). Even the laboratoryrecommends looking at this data only qualitatively.

Charcoal and Dosimeter Sampling:

  1. Although the report summary indicates that all samples were analyzed for BTEXand hydrocarbons, many samples were analyzed for benzene only.

  2. Up to a 15% breakthrough of hydrocarbons to the back half of the charcoal tubemay indicate that volatile organics such as benzene and toluene may havedesorbed from the charcoal during sampling.

  3. Of the contaminants analyzed, none of the compounds identified were found atlevels that would cause odor complaints; therefore, the cause of the complaintshas not been found.

  4. Analytical detection limits are above health-based screening levels, so a healthrisk evaluation cannot be completed.

(3) Bossier City Indoor Air Data, ENTEK, 1990-91.

This data appears to be ENTEK analytical results for all samples analyzed from 1990-1991. Much of the data is included in the Indoor Air Monitoring Report, Alexis Park ApartmentComplex, ERM-Southwest, Inc., (including Appendices A-H). However, several analyticalsheets were present that were not included in the ERM report. Other than sample ID andproject number, no chain of custody accompanies these data. This disallows any healthinterpretation of this data. The results do indicate the presence of VOCs other than BTEX,which indicates possible human exposure to other site-related compounds that have not beenwell characterized to date. The results are summarized in Tables 5 & 6. If sample type andlocations are found and presented, this review will be amended accordingly.


Table 5.

ENTEK Air Analysis--Unidentified Sample Types and Locations, March through August, 1990. All concentrations in ppm.
Contaminant MW Hdspc #90-032B Bag # 90088-01 Bag # 90087-06 Bag # 90088-02 Bag # 90095-01 Bag # 90052-02 MW
ERM-SG16A1
MW
ERM-SG16A3
Methane 5,989 17,583 68,800 1,705 2,571 76,434 484,612 <1
Chloromethane 3.98 3.79 5.86 10.35 0.17 4.49 9.32 Unk
Vinyl Chloride 0.36 Unk 0.39 0.17 Unk 0.10 <0.3 Unk
Methylene Chloride             4.95  
1,2-dichloroethane 0.09   <0.01       ND (<0.3)  
1,1-dichloroethane   0.04         ND (<1.1)  
Acetone Unk 19.76     0.52   473.10  
1,1,1-trichloroethane 0.01 <0.01 0.01 <0.01   <0.01 ND (<0.3)  
1,1,2-trichloroethane           <0.01 1.94  
Vinyl Acetate <0.01   <0.01   <0.01   42.39  
Benzene 0.59 0.53 6.63 0.79 0.02 0.42 ND (<0.3)  
Toluene 0.09 <0.01 0.15 0.20   0.03 0.83  
Ethylbenzene 0.12   0.08 0.64   0.06 ND (<0.3)  
Total Xylene 0.12 <0.01 0.08 0.17   0.06 ND (<0.3)  
2-Hexanone           0.60    


Table 6.

ENTEK Air Analysis--Unidentified Sample Types and Locations, March through August, 1990. All concentrations in ppm.
Contaminant B151 B152 B161 B171 B172
Chloromethane 11.47 9.60 0.70 0.34 6.75
Vinyl Chloride 0.32 0.23 <0.01 <0.01 0.14
Methylene Chloride <0.01 1.18 0.25 <0.01 <0.01
Acetone 168.93 125.34 67.43 272.89 422.21
Carbon Disulfide <0.01 <0.01 <0.01 <0.01 <0.01
2-Butanone <0.01 0.22 <0.01 <0.01 <0.01
1,1,1-trichloroethane <0.01 0.09 <0.01 <0.01 0.03
Bromodichloroethane <0.01 5.58 0.02 <0.01 <0.01
Benzene 0.24 0.24 0.06 1.04 1.16
2-Chloroethyl-vinylether <0.01 0.28 <0.01 0.07 <0.01
Toluene 0.03 0.03 0.03 0.24 0.29
Ethylbenzene 0.03 0.03 0.03 0.27 0.43
Xylenes <0.01 0.02 0.04 0.22 0.44
Vinyl acetate 0.02 <0.01 <0.01 <0.01 17.80

Limitations of the data:
Without knowing where the samples were collected, what air was sampled (i.e., soil gas, indoor air,monitoring well headspace), it is not possible to use this data for public health purposes. It can beused to indicate that many of the samples have contaminants similar to results of previous indoor airsamples. It also indicates that indoor air should be analyzed using EPA Method TO14--looking forall the compounds listed in the method.

(4) Indoor Air Data, ALCHEM, 1/30/90.

In January 1990, Alchem , Inc. analyzed 9 indoor grab air samples from Alexis Park for C1-C6compounds and for BTEX. The laboratory reported that all of the benzene results are elevated dueto coelution of unidentified compounds. Based on this statement, it is likely that all of thisinformation is suspect.

(5) Bossier City Indoor Air Data Sheets, LDEQ Air Toxics Lab, 1993 (Carriage Square andAlexis Park data).

This data was collected from June through November of 1993. The information available consists of some sampling location descriptions, chain of custody forms, and laboratory analysis sheets. Table 7 summarizes the sampling results in Alexis Park. Table 8 summarizes data from Carriage Square.


Table 7.

Summary LDEQ 1993 Indoor/Ambient Air Data, Alexis Park Apts. Concentrations in ppb, unless noted
Contaminant Apt 501
(1 sample)
Apt 505
(4 samples)
Apt 901
(4 samples)
Apt 1307
(4 samples)
Up- / Down-Wind
(ambient)
Methane (ppm) 1,320 Unk Unk Unk Unk
Benzene 223.7 17.53-42.76 2.38-5.32 0.61-5.72 1.0 / 1.2
Toluene 170.6 5.53 - 9.28 10.65-11.67 4.14-6.10 0.88 / 0.90
Ethylbenzene 34.8 0.6 - 1.72 0.96 - 1.21 0.30 - 0.93 0.15 / 0.14
Xylene (total) 37.4 3.3 - 8.41 5.45 - 7.31 2.67 - 4.24 0.44 / 0.52
Styrene 21.0 Unk Unk Unk Unk
1,2-DCA Unk 2.00-9.24 ND - 0.1 0.43 - 0.95 0.17 / 0.19
1,1,1-TCA Unk 0.82 - 1.32 0.48 - 1.13 ND - 0.11 0.21 / 0.25
Carbon tetrachloride Unk ND - 0.09 ND - 0.31 ND - 0.11 0.14 / 0.15
TCE Unk ND - 0.31 ND - 0.28 ND ND / 0.02
PCE Unk ND - 6.72 ND - 0.09 ND 0.04 / 0.04
Chlorobenzene Unk ND - 4.13 ND - 0.11 ND - 0.20 0.02 / 0.02
Cumene 16.2 0.17 - 0.49 ND - 0.18 ND - 0.07 0.03 / 0.03
C4 - C14 THC Unk 5,360 - 36,900 104 - 470 930 - 2,200 22 / 30
Unk = unknown if sample was analyzed for the compound
ND = not detected


Table 8.

*Summary LDEQ 1993 Indoor Air Canister Data, Carriage Square Town Home. Concentrations in ppb, unless noted
Contaminant 6/21 sample #C93-0246 6/21 sample #C93-0247 11/14 sample #C93-0396 11/14 sample #C93-0397
Methane (ppm) ~910 ~320 ~1,770 ~1,430
Benzene 138.8 67.7 160.0 22.5
Toluene 46.0 17.0 22.0 15.0
Ethyl-benzene 14.5 ND 24.5* 12.0
Xylene (total) 4.9 ND 56.5* 79.5
Cumene ND ND 2* ND
Styrene ND ND 32.0 5.5
* = Low confidence level in the data; more than 25% difference between the results obtained in 2 replicate samples

Limitations of the data:
(Alexis Park):
Samples were collected over a short period of time, and are likely not reflective of 12- to 24-hour orchronic exposures. It is not clear if all samples were analyzed for the same contaminants. Noinformation was available about the purpose or objectives of this sampling (i.e., whether it was doneas a result of odor complaints, or to make a health interpretation, etc.). Therefore, we cannotcomment on whether the objectives were met.

(Carriage Square):
Samples are grab samples (although they were evacuated canister samples), and are therefore notlikely to be reflective of 12- to 24-hour exposure or chronic exposure scenarios. No informationaccompanied the data as to what initiated the sampling, why specific residences in Carriage Squarewere sampled, or if any follow-up occurred. The DEQ site manager stated that sampling was donein Carriage Square residences because of residents' complaints of odors. VOC analysis was limited. EPA Method T014 or equivalent should have been done.

(6 ) Indoor Air Screening Report, OXY USA Inc., Bossier City, LA. Law EnvironmentalInc., November, 1993.

Indoor air screening using a flame ionization detector was done from June 29-September 24, 1993in residences where high levels of soil gas were found during the 1992 Soil vapor Investigation(reported in January, 1993). The results of the indoor air screening would be used to chooselocations for more thorough indoor air sampling.

Indoor air screening measurements were scheduled three times per month over a three month period(June 29-September 24 1993). Samples were taken from outside at the residence door and then inthe breathing zone (4.5 - 5.5 feet above the floor) in all the residence's rooms. In addition, readingswere taken inside cabinets, underneath sinks, along pipes and inside the wall space. Any FIDreadings above 500 ppm were reported to LDEQ and LOPH, and these units were sampled again. Ifhydrocarbon levels were above 10, 000 ppm the Bossier City Fire Department was to be notified.

Indoor air screening tests were performed over 4000 times at 419 locations which were monitoredduring the 3 month time period. None of the FID readings exceeded 20% of the lower explosivelimit for methane (10,000 ppm).

Limitation of the Data:

  1. This sampling episode was a screening test and did not allow for separating out individualcompounds. Instead, contaminants were all grouped together as total hydrocarbons. Theresults of the screening tests is helpful for determining future sampling locations wheremore thorough analysis of contaminants will be done but it is not useful in evaluatingexposure to contaminants and the health effects that might occur.

  2. A sampling schedule of 3 times a month for 3 consecutive months is not sufficient toevaluate levels of hydrocarbons that may fluctuate throughout the month and year.

(7) Indoor Air Monitoring and Analysis Report, Former Arkansas Fuel oil Refinery Site,Bossier City, LA. Law Environmental Inc., May, 1994.
This report provides the analytical results of the air monitoring and sampling as described in the"Air Monitoring and Analysis Supplement to Site Investigation Work Plan," Law CompaniesEnvironmental Training Center, November, 1991. The purpose of the sampling was to determineairborne concentrations of selected hydrocarbons in indoor areas on portions of the site. This datawas collected to assess the inhalation pathway in the Human Health Risk Assessment.

In February 1994, a total of 55 Summa® canister samples were collected from 36 indoor locations and analyzed for selected VOCs (C1-C6, and BTEX). Thirty-six of the samples were collected at breathing zone height; 13 concurrent samples were collected from inside wall and floor air space; and 5 samples were field duplicates. All but 2 of the samples were collected over a 24-hour period. Periodic real-time monitoring using an FID was conducted during these sampling events. Geographic sampling locations along with the # of dwellings per location are as follows:

Area # of Dwellings Sampled
Carriage Square/Village

4

Results, Inc.& Kutz Accounting

1

Plaza Circle

1

Rugby Area & Port-Au-Prince/Preston Place

5

Days Inn

2

Motel 6

2

La Quinta

3

Sheraton

2

Residence Inn & Cowboys

5

La Plaza & Moffits

1

Alexis Park

9

First United Church & Morrison's

1

According to this report, selection of the 36 sampling locations was based on results of the June - November, 1993 sampling at Alexis Park and Carriage Square dwellings (Bossier City Indoor Air Data Sheets, LDEQ Air Toxics Lab and Indoor Air Screening Report, Law Environmental, November, 1993). The rationale for choosing sampling locations was presented as follows: "Individual locations were selected from one building in the top 5%, middle 5%, and bottom 5% of the breathing zone height sampling with the flame ionization detector. This process resulted in the selection of 23 individual locations for sampling. .....". Only 5% of the residences with the highest hydrocarbon levels during the screening phase were sampled again. Two of the 36 locations did not allow access--2 additional locations were found. The information reviewed by ATSDR indicates that Alexis Park Apartment #501 was the only indoor location sampled in both the 1993 and February 1994 indoor sampling events.

The following is a breakdown (Table 1 in the 5/94 report) of the number of dwellings sampled according to ranking. Samples are grouped into breathing zone height (BZH) and inside wall (IW) locations. Again, data and information reviewed did not explain how a location was ranked; we assume that a dwelling ranked as 1, has the highest likelihood of indoor air contamination. We also assume that the ranking was based on past indoor air data and soil gas results. The dwellings sampled had rankings from 1 to 415.

Ranking Range # Dwellings Sampled in this sampling event
  BZH IW
1 - 9

5

2

10 - 19

5

1

20 - 49

4

3

50 - 99

6

4

100 - 149

1

0

150 - 199

3

1

200 - 249

8

1

250 - 349

0

0

350 - 415

4

1

 

36

13

Based on the "ranking," it appears that 50% of the first 20 most likely to have indoor air problems were sampled in the breathing zone; and 20% of the top 100 dwellings were sampled in the breathing zone. The analytical results of sampling are summarized in Table 9.


Table 9.

Indoor Air Analysis and Monitoring Analysis Report, Law Environmental, Inc., May 1994.
Compound Frequency of Detects Location Range (Over Detection Limit) (ppb) Ave Conc. Of Positive Results (ppb) Reference
Concentration
(ppb)
Benzene 19/36 BZ ~2.1 - 26 ~3.9 CREG 0.03
9/14 IW ~1.8- 119 ~11.3
Ethylbenzene 26/36 BZ ~0.33-11 ~1.33 EMEG 300
12/14 IW ~0.27-2.2 ~2.5
Toluene 25/36 BZ ~2.1-60 ~11.2 Chronic EMEG 1,000
9/13 IW 3.2 - 45 ~8.23
m,p Xylene 31/36 BZ ~1.4-49.5 ~5.2 Acute

EMEG 40

10/14 IW ~1.1-7.6 ~6.8
o-Xylene 27/36 BZ ~0.47-18 ~2.0 Acute

EMEG 400

12/143 IW ~0.33-3.8 ~4.0
Methane (ppm) 8/36 BZ ~23.8-233 ~20.4  
6/14 IW ~25 - 783 ~105
BZ - Breathing Zone (4.5 - 5.5 feet above the floor).
IW - Inside Wall (These samples were taken behind the kitchen sink wall).

Limitations of the data:

The samples were collected using EPA Method T014--but were not analyzed for the majority of theTO14-specified contaminants. It is not possible to tell if exposure to other site-related compounds isoccurring; therefore, it is not possible to fully assess the public health risk of the site. Noexplanation is given for taking breathing zone samples in 36 dwellings, but only taking samplesinside walls in 13 of these dwellings. Concentrations of the contaminants analyzed are below levelsthat would cause odor complaints.

By comparing sampling results from late 1993 and early 1994, for Alexis Apartment #501--a wide discrepancy in the contaminant concentrations in the breathing zone is noted:

Contaminant 1993 1994
(Alexis #501) (ppb) (ppb)
Benzene

223.7

~3.9

Ethylbenzene

34.8

~1.33

Toluene

170.6

11.2

Total Xylene

37.4

~7.2

Methane (ppm)

~1,300

~20.4


No other dwellings were sampled both in '93 and '94, making additional comparisons impossible.

Only 11 residences with the highest hydrocarbon levels were sampled again for a more thoroughanalysis.

(8) Remedial Investigation Summary Report, August 30, 1995. ERM-Southwest, Inc.

This report was a summary of soil gas and indoor air sampling and data presented earlier by LawEnvironmental Inc. (See #7 above).

(9) Volume VIII, Soil Gas Survey Results Remedial Investigation, Former Arkansas Fuel OilRefinery Site, Bossier City, LA. ERM-Southwest, Inc. June 7, 1995.

A soil vapor (gas) investigation was conducted at the site from June - September, 1992. The objective of the investigation was to determine the presence and horizontal extent of any surface or near surface hydrocarbons. The investigation included a soil gas survey and the collection of deep reservoir gas samples from 2 nearby producing oil and gas wells. The soil gas survey consisted of sampling on a 200-foot center grid. If significant FID readings were detected, the area would be gridded down to 110- to 30-foot centers. A total of 896 samples were collected at a depth of up to 7 feet (more shallow samples were collected if a 7-foot depth was not feasible). After FID screening, soil gas samples were taken (evacuated 125 ml vial). Duplicates were collected for 5 % of the samples. Trip blanks were shipped with the samples to the laboratory. If present, water or product samples were also collected for analysis (VOA vials). All soil gas samples and trip blanks were analyzed for C1-C4 and C5 plus (gasoline range) hydrocarbon concentrations (GC/FID). Confirmation of C5 plus analyses were performed on 63 selected samples to determine the concentrations of BTEX in the samples. Analysis of water and product samples was conducted to "fingerprint" or identify the source of the petroleum concentration. Results of BTEX analysis is summarized in Table 10.


Table 10.

Soil Vapor BTEX* and Corresponding Methane Ranges. From: Volume VIII, Soil Gas Survey Results Remedial Investigation, Former Arkansas Fuel Oil Refinery Site, Bossier City, LA. ERM-Southwest, Inc. June 7, 1995.
Contaminant Number of
Samples where Contam. Detected
Range (ppm)** Average (ppm)**
Methane*** 63/63 556 - 719,753 210,879
Benzene 62/63 ND - 196 43.3
Ethyl
benzene
48/63 ND - 31 5.3
Toluene 60/63 ND - 103 19.9
Xylene 62/63 ND - 50 10.3
* From confirmation analysis of 63/898 soil gas samples
** Detection limit ~1 ppm
*** Highest methane concentration found in the 898 soil samples was 719,753 ppm but the highest methane concentration found during confirmation analysis was 654,878 ppm.

Limitations of the data:

Results are helpful in that they define the extent of methane concentrations in the soil gas on the site. Analysis of additional compounds would have assisted in finding contaminants unique to the site that could be looked for in residences.

(9) Resource Document, Volume 2, Appendix 5, July 1988.

Between April 1985, and November 1987, 7 different events lead to various parties (EPA,properties owners, PRPs, etc) conducting sampling of surface and subsurface materials. The eventswere initiated when construction projects (commercial and home owner) unearthed tar-likesubstances and discolored soil. Various types of samples (grab, composite) were collected andanalyzed for metals, petroleum, and/or volatile organic compounds.

Locations sampled include the access road to the Bossier Crossroads Shopping Center (during roadconstruction); old process and petroleum waste disposal areas; a home on Carriage Square Drive(due to a resident digging post-holes); Alexis Park Apartments (during construction, tanks, pipes,and discolored soils were found during excavation activities); and in Alexis park during a ditchcave-in victim rescue operation. Table 11 displays contaminants and their concentration ranges,when detected, from these 7 episodes.

Limitations of the data:

The reports contain data that may be compromised because of possible inconsistencies in analysisand processing of samples. A quality control report was not available for all sampling episodes andthe quality control data that was available had poor recovery for spiked samples in some instances. This data cannot be used to estimate human exposure; however, it can be used to assist indetermining specific contaminants (or groups of contaminants) that should be further investigated inthe soil gas and indoor air.

(10) Surface Soil Sampling Results, Volume III, Remedial Investigation, Former ArkansasFuel Oil Refinery Site, ERM-Southwest, Bossier City, Louisiana, June 30, 1995.

During surface and subsurface soil sampling (0-2 feet) during June-September of 1992, a tar-likematerial was found on some residential and commercial properties. A total of 3 samples, each froma different location, were taken and tested for semi-volatiles.

Limitations of the data:

Metals were not measured and volatiles were only screened for one of the three samples. The results are displayed in Table 12.


Table 11.

1985-87 Tar-like material sampling result summary
Contaminant Frequency of
Detects
Concentration range (ppm)
Benzene 3/23 0.092-0.15
Ethylbenzene 4/23 0.06-6.4
Toluene 3/23 0.0039-0.46
Xylene 4/23 0.038-35
Chlorobenzene 2/5 0.06-0.08
Chloroform 1/23 0.04
Methylene Chloride 2/23 11.0-569
1,1,1 Trichloroethane 1/23 4.12
1,1,2 Trichloroethane 1/23 0.021
Tetrachloroethylene 1/23 4.80
PCB isomer 1242 1/23 8.5
PCB isomer 1254 1/23 2.0
Naphthalene 1/23 0.003
N-Nitrosodiphenylamine 3/23 0.140-11.0
Bis(2-Ethylhexyl)phthalate 3/23 0.0043-4.3
Chrysene 3/23 1.90-14.0
Phenanthrene 4/23 3.20-13.0
Pyrene 4/23 1.80-15.0
2-Methylnaphthalene 5/23 2.40-11.0
Bimethylnaphthalene isomer 1/23 9.60
Molecular Sulphur 1/23 1.7
Polynuclear Aromatics 16/23 6.8-82
Arsenic 20/23 0.001-18
Lead 23/23 0.05-6980
Mercury 11/23 <0.020-1.3


Table 12.

August, 1992 - Tar-like material sampling results from 3 samples taken during surface soil sampling episode. Metals (arsenic, barium, lead, and mercury)were not tested for in any of the three samples. Volatiles were tested for in one sample with a FID.
compound (ppm) sample #511 sample #512 sample #513
naphthalene 1.3 ND ND
2-methylnaphthalene ND 18 19
phenanthrene 170 85 ND
anthracene 41 12 ND
fluoranthene 42 11 ND
pyrene 320 64 29
benzo(a)anthracene 180 210 ND
chrysene 280 210 ND
benzo(b)fluoranthene 98 59 ND
benzo(k)fluoranthene 98 59 ND
benzo(a)pyrene 160 26 ND
indeno(1,2,3-cd)pyrene 54 ND ND
dobbins(a,h)anthracene 22 ND ND
benzo(g,h,i)perylene 140 ND ND
benzo(a)pyrene
equivalents
330.7 42.98 0.029

ND-not found above detection limits


Appendix C: Public Comment on the Highway 71/72 (Old Citgo Refinery) Site Public Health Assessment

Extensive comments were received from a consultant to the PRP. Many of them followed a similarline of thought but were directed toward differing locations within the PHA. These comments canbe roughly grouped into the following categories:

  1. The public comment version used unvalidated data and drew inaccurate and highly qualified conclusions

  2. Soil lead data and blood lead data were misinterpreted

  3. Difference in opinion regarding LOPH interpretation of air data, sampling duration and number of samples.

  4. The Public Health Assessment makes statements contradictory to the Baseline Risk Assessment

SEET has decided that the best way to address these comments is to provide general discussion aboutthese categories. The general discussion is then followed by the individual questions in the order inwhich they were received and the response. The response may be specific to the question or refer thereader to the discussion appropriate to that comment.

1. Validated Data

The Public Health Assessment is a document designed for the public. It is not an EPA Risk Assessment. The Public Health Assessment is mandated to be completed in 1 year of the National Priorities Listingof the site. The public comment and final version follow the initial version. Given the time restraintsand the goal that the document serve the public, the PHA does not always use complete or validateddata. ATSDR guidance provides for such an occurrence. The ATSDR guidance states that"Inadequacies, insufficiencies and discrepancies in the data or in the sampling and analytical techniquesused to obtain the data, as well as missing QA/QC information should be explicitly noted in the healthassessment." The PHA contains a section entitled "Limitations of the Data" where the inadequacies ofthe data are addressed.

2. Soil and Blood Lead

In certain areas of the site, surface soil is contaminated with lead. The areas of lead contamination withthe highest lead concentrations have been covered with grass to reduce the likelihood that residents maycome in contact with soil. Young children (6 months through 6 years) are the most sensitive populationto lead exposure in soil and to the health effects of that exposure. In July 1995, the LouisianaDepartment of Health and Hospitals/Office of Public Health/Section of Environmental Epidemiologyand Toxicology (LDHH/OPH/SEET) and the Agency for Toxic Substances and Disease Registry(ATSDR) conducted a voluntary blood lead screening to determine if children on-site had elevatedblood lead levels. Blood lead values were found to be in the normal range, below the levels requiringmedical follow-up. Though the blood lead levels of children tested in the exposure investigation werebelow levels requiring follow-up, only 55 out of the approximate 300 children ages 6 months through6 years who live on-site, volunteered for testing. The children tested may not be representative of thelarger population of children on-site.

3. Difference in opinion regarding LOPH interpretation of air data, sampling duration and number ofsamples. (These comments sometimes overlap with those regarding the use of unvalidated data)

A request has been made by EPA to review the current LOPH Advisory regarding the indoor air qualityin Apartment #501of the Alexis Park Apartments. To address this request, LOPH will re-evaluate thedata (Omitting data points which were rejected) and activities conducted since the PHA was written andaddress these issues in a separate Health Consultation.

4. The Public Health Assessment makes statements which contradict the Baseline Risk Assessment.

ATSDR guidance states:

Deliberate differences exist between ATSDR's health assessments and EPA's risk assessments. The twoagencies have distinct purposes that necessitate different goals for their assessments. . . .

Thus while a risk assessment conducted under EPA's Remedial Investigation/ Feasibility Study(RI/FS) process is used to support the selection of a remedial measure at a site, an ATSDR healthassessment is a mechanism to provide the community with information on the public healthimplications of a specific site, identifying those populations for which further health actions orstudies are needed.

Public Comment on the PHA

Overall Comments on the PHA

  1. The characterization of the Highway 71/72 Refinery Site as a "public health hazard" isclearly unwarranted and irresponsible given the amount of validated site-specific data andprevious, scientifically valid interpretations of the potential human health hazard.

  2. Based on the findings of numerous sampling events, with contaminant levels for severalchemicals above health hazard levels, and the current nature of the site, thischaracterization is indeed correct.

  3. The draft PHA demonstrates that its authors did not consider the complete database of Siteinformation and reports that provide valuable scientific information supporting the lack ofany appreciable current or future health hazard at the Site. The draft PHA contains nodiscussion of the extensive LDEQ and LOPH involvement in the project including workplan development and approval, field oversight, split sampling, report review and approval and monthly reporting.

  4. There is a wealth of information existing for this site, and it has all ben taken intoaccount. There has also been lots of agency participation on the part of LDEQ, LOPHand EPA, however, there has not been total agreement between OXY and the agenciesabout the practices going on at the site. When the fact that there is appreciable futurehealth hazard existing at the site is proven, it will be further addressed.

  5. The draft PHA generally identifies constituents of concern in an appropriate manner, butthen discusses "site-related" constituents/media of concern inconsistently and includes wide-ranging speculation about other substances.

  6. There is a procedure for identifying contaminants of concern, however, during samplingevents, when a contaminant is identified, that may not be normally associated with thenature of a site, this contaminant is also addressed and assessed as to possible healtheffects.

  7. The draft PHA provides a screening evaluation of exposure pathways for the constituents ofpotential concern, but fails to adequately consider and/or appropriately document dataquality and validation, the source(s) of potential constituents of concern, quantitative aspectsof the fate and transport of certain constituents/media, and the reasonableness of theassertions that significant exposure probably has occurred or will occur.

  8. Your comment has been noted.

  9. The draft PHA fails to address data quality as required by the ATSDR Guidance Manualand as a result, uses unvalidated and non-representative data to draw erroneous conclusionsabout the health implication of the Site.

  10. The draft PHA does in fact address data quality. Limitations of the data are addressed inAppendix B on pages B-5, B-8, B-11, B-13, B-14, B-17, B-19, and B-20.

  11. The draft PHA lacks appropriate consideration and discussion about probable exposureduration, frequency, fluctuation, and bioavailability with respect to the potential for keyconstituents of concern to cause harm, and derives inappropriate conclusions based onincomplete analysis and implausible assumptions regarding the available data on exposureand dose.
  12. The draft PHA follows ATSDR guidelines and has the agency's concurrence.

  13. By ignoring the 1994 Baseline Risk Assessment and the related peer review and datavalidation process, the draft PHA arbitrarily neglects information essential to determineobjectively the potential health effects, if any, of the Site, and compromises the credibility ofthe draft PHA as a means of responsibly informing the Bossier City community aboutpotential health risks.

  14. This comment has been noted.

Detailed Comments on the PHA

  1. The Baseline Risk Assessment and the LDEQ- and LOPH- approved investigations to date clearly show that sufficient validated data and information exist to demonstrate that the Site does not exceed EPA guidelines as applied in similar circumstances.
    This comment has been noted.

  2. "There are three reasons why the Highway 71/72 Refinery Site has been described as a public health hazard:" This concern "lead concentrations reported in soil would pose a future health risk to young children if they frequently come in contact with the lead contaminated soil." is not supported by the facts. It does not recognize the facts that: 1) the 1995 LOPH/ATSDR blood lead study found the blood lead levels in children living on the Site to be in the normal range, below the levels even requiring follow-up, and 2) the fact that OXY will remove these areas of surface soil containing elevated lead levels once EPA approval is obtained. The latter point is important to the health assessment because at similar sites (such as the Sinclair refinery in New York) ATSDR has correctly incorporated planned remedial actions into its health assessment and thereby reached a determination of no apparent public health hazard.

  3. At the lead levels present on site at the time the PHA was written, frequent exposure to children on site would pose a health risk. Fortunately, blood lead levels in the children tested were below levels requiring intervention. Upon EPA approval of the remedial plan, and even upon remedial action, further evaluation of the area should be undertaken. Until then, exposure to the lead contaminated soil, especially for children, should be limited.

  4. "benzene concentrations reported in indoor air (1990-1994) may pose a health threat if the short-term benzene measurements are representative of daily exposures" The draft PHA itself questions the validity of the sampling events upon which this speculation is based. The draft PHA cannot rely upon a few questionable, unvalidated measurements to derive conclusions about potential health impacts when a wealth of well documented validated data is available. In PHAs at other refinery and related sites and in the ATSDR PHA Guidance Manual, ATSDR has recognized that only validated data should be used in health assessments. The validated data, which OXY used in its Baseline Risk Assessment, should be the only basis for health assessments. The validated benzene data do not support the conclusions reached in the draft PHA.

  5. Short-term benzene measurements were obtained, at levels, that if there was daily exposure at that level would present a health hazard. However, further, more long-term sampling may give a better idea of the actual exposure scenario.

  6. "methane concentrations measured indoors and in soil gas may pose a potential explosion hazard. As a precautionary measure, Building 5 of the Alexis Park Apartment complex has been closed under the order of the state health department." This statement is incorrect and misleading. No potentially explosive levels of organic vapors or methane have ever been measured in indoor air despite the over 60,000 measurements recorded from 1990 through 1994. Elevated levels of methane have ben measured in the soil gas but have never been shown to present an explosion hazard. ATSDR did not declare the Treasure Island Naval Station Site a public health hazard despite the fact that soil gas levels of methane were four times the highest level recorded under Building 5 at Alexis Park.

  7. Sites are evaluated on a site by site basis. It states that the levels may pose a potential explosion hazard, and upon reaching a percentage of the explosive limit, and with the knowledge of soil gas levels, concern about methane levels has been expressed.

  8. This speculation "though the blood lead levels of children tested in the exposure investigation were below levels requiring follow-up, only 55 out of the approximately 300 children ages 6 months to 6 years who live on-site volunteered for testing. The children tested may not be representative of the larger population of children on-site." is no more justified by the facts than the converse; that the 55 children tested are indeed representative of the larger population of children on-site. Obtaining a less than 100% participation is not an excuse for denying the results of the testing which clearly show no health concerns related to the lead contaminated soil even in this most susceptible population. The testing also validates the Baseline Risk Assessment which predicted that no health effects would be expected.

  9. Health issues are often critical ones, and this agency is charged with protecting the interest of public health. The fifty-five children tested is not representative of half of the childhood population living on the site. These may be children that don't play outdoors, and the exposed children weren't tested. To make health decisions with conservatism, more often protects public health.

  10. No site investigation will ever have all of the information which could possibly be obtained. The draft PHA does not specifically identify how filling these purported data gaps would have any impact upon the health assessment nor despite vague references to subjective criteria, does it identify specific inadequacies in the validated data. However, in spite of these purported "data gaps", the extensive testing performed over the four year period for a wide variety of potential constituents shows that indoor air quality at the Site is no more a health hazard than typical U.S. indoor air and that the validated data collected are sufficient to conclude that the Site does not pose a health hazard based upon indoor air quality.
    This comment has been noted.

  11. The selection of constituents to be analyzed and the selection process and final list were approved by LOPH and LDEQ in advance and consistently included those constituents most likely to be related to oil and refinery processes and having the most significant potential to pose health risks. Analyzing for other potential constituents, many of which have multiple sources unrelated to the former refinery is not warranted.

    Contaminants have appeared on this site, which may not be normally related to processes associated with this site, however, they appear at levels of concern, and further testing is warranted to correctly and completely ascertain possible health risks related to those chemicals.

  12. "sampling was too infrequent and brief to accurately assess residents' exposure to air contaminants. There was no concurrent monitoring of the soil gas and indoor air quality." This assertion is not justified by the facts. The samples taken were representative of the indoor air being sampled and were taken at many different times and places throughout the years. There is no plausible scientific basis supporting the inferred assumption that sampling data for indoor air are not representative of the upper bound and/or long term exposures. Sampling events were designed to collect data at locations which would tend to over represent those areas where past measurements had shown elevated concentrations. The suggestion that a lack of "concurrent" monitoring of soil gas and indoor air somehow detracts from the existing data is erroneous. The draft PHA erroneously concludes that concurrent monitoring will provide additional insights into residents' exposure or the source of indoor air constituents. In addition, the draft PHA presents no data to refute the extensive work done by OXY's consultants which shows there is no correlation between soil gas composition and indoor air quality at the Site and there are no excessive health risks to residents based on reasonable maximum exposure scenarios, including the indoor air pathway.
    This comment has been noted.

  13. The main reason that the studies to determine the origin of indoor air constituents have not been conclusive is that multiple sources appear to exist for the presence of constituents in indoor air, including natural and synthetic materials as well as the personal habits and lifestyles of the residents. Cigarette smoking, automobile exhaust, and household cleaning products and pesticides are just as likely to be the source for any indoor air constituents as any of those mentioned in the draft PHA. Regardless of the source, the indoor air quality is just as typical (as shown by EPA studies) as indoor air that one would expect to find in any U.S. city.
    This comment has been noted.

  14. The extensive, validated data (including 24 hour measurements) collected with some frequency over the years and analyzed for the refinery-related constituents of potential concern to public health and the studies showing no correlation between soil gas composition and indoor air composition are sufficient to make a determination of "no apparent public health hazard" and the recommendation for additional air sampling is unjustified.
    This comment has been noted.

  15. Even though these areas are currently covered in thick grass, thereby limiting exposure, OXY has agreed to remove the surface soil with elevated lead concentrations. This action will completely eliminate the above concern. However, OXY is prevented by law from performing the removal action until EPA approves the work plans. To date, EPA has refused to allow OXY to perform the recommended removal actions.

  16. Upon approval and implementation of the removal action work plans, the site will be re-evaluated.

  17. Subsurface soil samples did not extend to 7 feet (Page 3) and the last parenthetical phrase should be: "(greater than 2 inches - 2 feet)".

  18. The appropriate correction to the background section of the document has been made.

  19. ATSDR and LOPH have an obligation to assess the validity behind any anecdotes before giving them merit in a health assessment. Earlier versions of the draft PHA state that the LOPH and ATSDR investigations of these allegations showed that they were unfounded.

  20. Common cancers are addressed in the document. Anecdotal information from the community is not validated prior to its inclusion.

  21. Validated data are a prime requirement for any assessment. OXY used only validated data in the Baseline Risk Assessment. Some of the data used in the draft PHA to justify the conclusions do not meet the requirements of ATSDR's own Guidance Manual and these data should have been rejected or qualified.

  22. There exists more data for this site than the validated data spoke of. When data becomes available, if it indicates a health hazard or even a possible health hazard, it is closely examined. Since the data validation did not happen before the completion of the document, and levels in the unvalidated data were cause for concern, it was included in the document.

  23. This very important criterion "Comparison of the on-site data with background concentrations" was virtually ignored in the draft PHA for indoor air measurements.

  24. This issue along with many other issues regarding air sampling, soil gas sampling and the data, may be addressed in a separate document.

  25. These statements "A total of 25 of the 360 soil samples were split (greater than 5%) for quality control assurance. An additional 15 confirmatory samples were obtained in November 1992 in 3 areas to evaluate the lateral extent of contamination" inadequately reflect the breadth and nature of the sampling program.

  26. The reader's referral to the referenced document will give them more information.

  27. Errors in page 6's Table 1 need correction, and the CREGs and SSLs need better explanation.

  28. In the introduction to the Environmental Contamination Section of the document, the varying comparison values are explained. The appropriate corrections to Table 1 have been made.

  29. The wording of this statement "The maximum levels for benzo(b)fluoranthene, benzo(a)anthracene, and indeno(1,2,3-cd)pyrene were above there comparison values." erroneously leads one to believe that all samples were above their comparison values. In fact, only a few samples exceeded the comparison values.

  30. It is noted that hits of the above mentioned contaminants were above the comparison values, not all of the samples had contaminant detects above comparison values.

  31. Table 3 on page 8 contains an error. The number of samples column for lead should read 109/109.
    The appropriate correction to the table have been made.

  32. The benzo(a)pyrene equivalent levels are below the EPA screening levels presented in Tables 2 and 4 of the draft PHA.

  33. This document's Tables 2 and 4 do not state the concentration of benzo(a)pyrene equivalents exceed comparison values.

  34. Some corrections to Table 4 on page 9 need to be made.
    The needed corrections have been made.

  35. This statement is incomplete "Total volatile organic compounds (VOCs) concentrations in soil gas were screened at the three soil depths using a flame ionization detector (FID)."
    Page 10 has been modified to more completely describe field procedures.

  36. "The highest concentration was greater than approximately 10,000 ppm and was found in a sample taken near the United Methodist Church." The reading was actually taken near the Days Inn, not near the church.

  37. The church is important because attendees could receive weekly exposure or could be exposed both at home and at church.

  38. "A sample taken from Alexis Park Apartment Complex and one from a single family adjacent to Alexis Park had concentrations of VOCs at approximately 4000 ppm and 1500 ppm respectively." It should be made clear that the second sample was taken from the yard of a single family residence.
    This comment has been noted.

  39. No tar samples were found in or collected from anyone's home.

  40. The document has been revised to read that the tar sample was taken from soils on residential properties.

  41. "As with indoor air, the analysis was for methane and BTEX compounds only." This is not a correct statement. Samples were analyzed for a variety of hydrocarbon compounds typically associated with refinery operations.

  42. Various samples were analyzed for various constituents. You are correct that it is important to specify which samples were analyzed for which analytes.

  43. Vinyl chloride, a synthetically manufactured chemical, is not commonly found with oil and refinery operations. Sulfur compounds have characteristic odors which are often detectable at levels far below any level required for health effects.

  44. There are some compounds, often those containing sulfur, which can be detected at very low concentrations by the human nose. At the low levels at which the nose registers the odor, there are no measurable adverse health effects. These odors can however be unpleasant and can trigger headache or nausea. Some states have implemented 'nuisance" or 'quality of life' ambient air standards for hydrogen sulfide. Complaints of odor are not automatically dismissed in the Public Health Assessment process.

  45. There is no correlation between odors and health effects, and no indication that reported odors are related in any way to historic activities at the Site. OXY is not aware of odor reports in the mid-1980's. There were odors reported in 1990. Odors reported before or at the beginning of this decade cannot be validated or confirmed by samples taken in 1996. There have been no reports of odors in recent years.

  46. There are some compounds, often those containing sulfur, which can be detected at very low concentrations by the human nose. At the low levels at which the nose registers the odor, there are no measurable adverse health effects. These odors can however be unpleasant and can trigger headache or nausea. Some states have implemented 'nuisance" or 'quality of life' ambient air standards for hydrogen sulfide. Therefore, complaints of odor are not automatically dismissed in the Public Health Assessment process.

  47. Detection limits are not "set" but are functions of the sample matrix, the instrument, the analyte, and other factors beyond the control of the investigators.

  48. This fact is true, however based on those functions and factors, a detection limit is "set" that best accounts for and utilizes these factors.

  49. This speculation "The duration of some sampling events was often too short (minutes to a few hours) and may not be representative of actual conditions to allow an adequate health evaluation." is unjustified. Thousands of measurements and samples were taken at different times and places over years. There is no question that, in the aggregate, OXY's data are the representative of actual conditions at the Site and the validated data easily allow an objective health evaluation to be made.

  50. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  51. This subjective conclusion "Sampling frequency was low and not continuous." does not accurately characterize the extensive sampling that has been done at the Site.

  52. There has been extensive sampling regarding certain areas of contamination regarding this site. However, regarding other aspects, like the area of indoor air, sampling events have been lacking in obtaining results showing the benefits of any remedial efforts.

  53. "Weekly or monthly indoor air monitoring of methane that was conducted might not be representative of the daily fluxes in methane concentration." This is speculation not science. There is every reason to believe that the data are representative of Site conditions and the daily fluxes. The extensive nature of the previous investigations clearly indicates that the previous testing is representative.
    This comment has been noted.

  54. All validated data met holding time limitations. If the draft PHA were to rely only upon validated data, statements like this "Holding times on some indoor air samples (prior to analysis were too long." would be unnecessary.
    Please refer to Comment #14.

  55. The "limits of the data" are the very factors which prevent them from being validated. Since these data are not validated, they cannot be used as the basis for drawing conclusions. The need for qualifiers such as "suggests", and "may exist", and "some of" and "if representative" and "may pose" clearly shows speculation. Only validated data should be used in the health assessment.
    This comment has been noted.

  56. The draft PHA is relying upon unvalidated data to discredit validated data and to imply, without credible evidence, that a potential health impact may exist at this site.
    This comment has been noted.

  57. In fact it is known that some of the sources of benzene are not site related. For instance, automobile exhaust and cigarette smoking are sources of benzene in indoor air. Soil gas sampling and indoor air measurements were performed under LOPH and LDEQ approved plans and show no correlation between soil gas composition and indoor air composition.
    This comment has been noted.

  58. Table 5 on page 12 contains factual errors.
    The table is factually correct, however, in areas like the Carriage Square Apartments and Alexis Park Apartments where there are numerous units with levels above comparison values, we often do not list every unit or room.

  59. Residents of Alexis Park building 5 were evacuated at the recommendation of the fire department after January 19, 1990 because the initial testing indicated total organic vapor concentrations greater than 1000 ppm. No detected benzene concentrations greater than 1000 ppm have ever caused any agency-ordered evacuation of any building on the site.

  60. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  61. A link is implied between one, single, sole, source of methane and factors that may affect fluxes in some "indoor air concentrations" and ignores the fact that there are multiple sources of methane.

  62. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  63. The sentence on page 13 should read "The testing of the VOC vapors in soil gas on-site reveals that these vapors consist primarily (more than 90%) of methane."
    The statement has been modified.

  64. The composition of soil gas is well characterized. The health effects of all the constituents were considered in the Baseline Risk Assessment which determined that there are no significant health risks.
    The composition of soil gas may be a factor in many indoor air problems existing at this site. Cracks in slabs as well as seepages may contribute to the indoor air contamination existing here.

  65. Table 6 on page 13 contains errors.
    The table has been modified to reflect the range of the contaminant's concentrations.

  66. Table 7 on page 14 contains errors.
    The appropriate changes have been made.

  67. Table 8 on page 15 contains errors.

  68. The range of the contaminant concentrations has been changed, and the maximum concentration of xylene now exceeds its EMEG of 40ppb. The appropriate changes to the document regarding this exceedence should be made.

  69. The data validation conducted by Gradient shows that the tar like material data from 1992 and 1995 were valid. The reports document that the chains of custody guaranteeing the integrity of the sample as it changed hands were present and in good order, and the lab procedures were acceptable.
    At this point in time, and upon the time of validation, data results may be valid, however, when this document was written, it is possible that reports were missing or misplaced.

  70. Some early data were not reliable (unvalidated) but subsequent, validated sampling contains reliable data which should be used to estimate exposures and, in fact, was used in the Baseline Risk Assessment.
    Please refer to Comment #14.

  71. The samples referred to on page 15 were collected in 1992 not 1993.
    This date has been modified.

  72. Metals and VOCs were included in the analysis of most of the tar-like samples (Page 15).

  73. They may have been included in the analyses, however, results for VOCs were limited, and data quality poor for metals, resulting in no obtained data.

  74. The extent of the groundwater sampling is not accurately reflected.
    This comment has been noted.

  75. The speculation that groundwater beneath the site contains hydrocarbons including polycyclic aromatic hydrocarbons and volatile organic compounds which may be contributing to soil gas and indoor air contamination, is not supported by the data.
    This comment has been noted.

  76. Table 9 on page 17 contains errors, and the latest version of Volume II of the Remedial Investigation Report is dated June 7, 1995 not August 30, 1994.
    This table has been modified.

  77. The potential for exposure to the tar material was evaluated in the Baseline Risk Assessment and found to result in no health hazard.
    This comment has been noted.

  78. The multiple sources of indoor air constituents have been identified and include common household materials and contamination resulting from personal habits of residents (such as cigarette smoking). However, the validated data used in the Baseline Risk Assessment show that no health hazards exist. In addition, the indoor air quality has been shown to be about what is typically expected in urban areas based on EPA studies.

  79. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  80. As discussed earlier, the draft PHA should distinguish between concentrations of methane and concentrations of combustible VOCs and not use them interchangeably.
    This comment has been noted.

  81. The Baseline Risk Assessment considered exposure from soil excavation conducted during activities such as digging ditches for utilities, or gardening in on-site yards and reached the conclusion that no unacceptable health risk was likely to be present.
    This comment has been noted.

  82. The presence of similar constituents in soil gas and indoor air samples does not, a priori, mean that they are related. The draft PHA continues to speculate about a connection despite the lack of evidence and despite the work by Gradient which refutes the draft PHA's hypothesis.

  83. The composition of soil gas may be a factor in many indoor air problems existing at this site. Cracks in slabs as well as seepages may contribute to the indoor air contamination existing here.

  84. Page 23 asserts a repetition of an invalid assertion which has been fully addressed and refuted earlier in this response document.
    This comment has been noted.

  85. The draft PHA leads readers to believe that risks were from PAHs using toxicity equivalency factors; however, no such analyses or calculations are presented for examination by the public.

  86. The PHA does not include step-by-step calculations of carcinogenic or non-carcinogenic health risks.

  87. Readers of the draft PHA are misled to believe that levels of benzo(a)anthracene detected in surface soils at the Site are essentially the same as those normally found in urban soils. In addition, the draft PHA finds that even these levels are of no health risk.
    This comment has been noted.

  88. The validated data shows that benzene levels in indoor air are not as high as the levels quoted. Furthermore, if all of the studies available regarding the health effects of benzene at concentrations less that 1 ppm show that no health effects are observed, it is unwarranted to arbitrarily reject those findings and determine that the health effects are "not known".
    This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  89. It is speculated about long term exposure at concentrations far in excess of and in direct contradiction to all of the validated data and the Baseline Risk Assessment based upon those validated data. Repetition of such speculation does not support classification of the Site as a Public Health Hazard.

  90. The many factors influencing this site, as well as the varying unknowns, and the presence of soil gas and indoor air contamination allow classification of this site as a public health hazard.

  91. Re: Page 25, The indoor air samples were collected by Law in 1994 not 1992.
    The appropriate correction has been made.

  92. Evacuations were ordered based upon FID readings, not measurements of specific components such as methane and benzene. Benzene measurements have never caused an agency-ordered evacuation of any building on the Site.

  93. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  94. The tens of thousands of indoor air measurements show that methane levels in indoor air were never a threat to health! The few, unvalidated elevated benzene levels reported are not sufficient to overcome the extensive body of validated data which was used in the Baseline Risk Assessment showing that there were no unacceptable health risks. Further testing is unwarranted.
    This comment has been noted.

  95. Indoor air sampling was not short term, but took place over a number of years, and samples were analyzed for an extensive list of potential refinery related constituents. The data are representative of indoor air quality. The sources of any indoor air constituents, as shown by the Gradient studies cited earlier, are more likely to be natural sources, cigarette smoking, household products, automobile exhaust and effects from personal lifestyles than soil gas.

  96. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  97. A more complete answer to residents would include the fact that these constituents (BTEX and Methane) are commonly found in indoor air and commonly associated with automobile exhaust and cigarette smoking and such findings are not unique to this Site.

  98. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  99. A more complete and accurate answer would be that tar like substances may be from asphalt paving, tars, or other tar sources and not, necessarily, related to the former refinery operations. As with any tar-like material from any source, direct contact should be avoided.

  100. The analysis of the tarry material indicates the presence of polycyclic aromatic hydrocarbons, volatile organic compounds, and metals (See Table 11, Appendix B). This data is not useable to estimate the exposures individuals might encounter but provides some indication of the materials that should be further investigated for their presence in indoor air and soil gas.

  101. The sources of any odors presently observed by residents may not be related to the former refinery operations at the Site. Odors, in and of themselves are not a health risk. While it is desirable for the residents to know the sources of odors, it does not, a priori, have bearing on the health assessment of the Site as it relates to former refinery operations. Further, no reports of odors have been received in recent years.

  102. There are some compounds, often those containing sulfur, which can be detected at very low concentrations by the human nose. At the low levels at which the nose registers the odor, there are no measurable adverse health effects. These odors can however be unpleasant and can trigger headache or nausea. Some states have implemented 'nuisance" or 'quality of life' ambient air standards for hydrogen sulfide. Complaints of odor are not automatically dismissed in the Public Health Assessment process.

  103. Methane, which is odorless, cannot be the source of odors regardless of the sources of methane. Methane is not a plausible health risk at the Site.

  104. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  105. Through blood lead level testing of children (the most susceptible populations), and through blood lead modeling, the areas of elevated lead concentrations have been shown not to pose a health threat. In addition, remedial actions for these areas will commence following EPA approval. Validated benzene concentrations reported in indoor air don not pose a health risk. A few, unvalidated, elevated levels do not justify the speculative extrapolation to deem benzene in indoor air a health risk. There is no evidence that methane under the slabs of the buildings poses a present or future physical hazard. The only appropriate classification for the Site under the ATSDR Guidance Manual is no apparent health hazard.

  106. Refer to Comment #66.

  107. The draft PHA shows itself that the measured levels of arsenic in soils are not a health concern and are at background levels. Due to the thick grass cover, the lead in these soils is less accessible than it was previously (when it had already been shown in the blood lead study not to pose a risk). Also, the soils containing elevated concentrations of lead will be removed after EPA approvals are obtained.

  108. Upon approval and implementation of the removal action work plans, a re-evaluation of the site will be further investigated.

  109. As previously discussed, more air data are not needed due to the extensive work already performed by Gradient which shows that; (1) constituent concentrations in soil gas do not correlate with those in indoor air, (2) measured levels of constituents in indoor air are not only representative of concentrations over time but are consistent with EPA's own findings on indoor air quality in urban areas unrelated to the Site, and (3) that automobile exhaust rather than soil gas is a likely source of BTEX constituents in indoor air.

  110. The composition of soil gas may be a factor in many indoor air problems existing at this site. Cracks in slabs as well as seepages may contribute to the indoor air contamination existing here.

  111. A more accurate statement than "Contaminants found in soil gas were found in indoor air samples." Would be that the constituents found in soil gas at the site are also found in indoor air samples throughout the United States, and are common constituents in indoor air. The correlation implied in the draft PHA is not justified by the facts.

  112. The composition of soil gas may be a factor in many indoor air problems existing at this site. Cracks in slabs as well as seepages may contribute to the indoor air contamination existing here.

  113. Tarry materials were analyzed and the results were evaluated along with potential exposure scenarios in the Baseline Risk Assessment. The Baseline Risk Assessment showed that the levels of PAHs and lead do not pose a health risk.

  114. The analysis of the tarry material indicates the presence of polycyclic aromatic hydrocarbons, volatile organic compounds, and metals (See Table 11, Appendix B). This data is not useable to estimate the exposures individuals might encounter but provides some indication of the materials that should be further investigated for their presence in indoor air and soil gas.

  115. OXY agrees with this precautionary statement, "Exposures to elevated levels of lead in the soil should be limited" and it agreed before the draft PHA was prepared, to remove the identified areas of soils containing elevated lead levels. OXY is awaiting EPA approvals to commence this removal action.

  116. Upon approval and implementation of the removal action work plans, a re-evaluation of the site will be further investigated.

  117. The soil gas was tested for a wide range of constituents related to oil refineries in accordance with the LOPH- and LDEQ-approved sampling and analysis plans. The BTEX compounds have been consistently analyzed at this site, vinyl chloride is not refinery related, and the sulfur compounds are highly odiferous and were not detected by odor.

  118. This comment has been noted.

  119. Since the Gradient studies show that there is no correlation between soil gas composition and indoor air composition and extensive analyses have been performed on both soil gas and indoor air, this suggestion has already been implemented and no further indoor air sampling is warranted.

  120. This comment has been noted.

  121. No indoor air measurement among the more than 60,000 readings has ever shown any level of methane at even one-quarter of the Lower Explosive Limit of methane despite daily and weekly monitoring of indoor air composition and fluxes. No evidence to date suggests that indoor air in any building or residence may present an explosion or fire hazard related to the Site. Therefore, since no evidence has ever been produced to support this concern, it should be eliminated form the PHA.
    This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  122. It is possible that some of the monitoring wells should continue to be monitored. The testing of monitoring wells can be performed under LDEQ or EPA oversight. However, all evidence to date shows that groundwater migration is not a health concern.

  123. This comment has been noted.

  124. Cited references should be corrected and the draft PHA should cite and incorporate the results from a number of other references.

  125. There is a wealth of information regarding this site and the occurrences surrounding it. Those interested in finding out what's in the other references may research them separately or visit the site's repository.

  126. This statement is not accurate "The Red River aquifer lies below the site with a distance of 12-14 feet between ground surface at the highest level of the aquifer." The top of the Red River alluvial aquifer is actually encountered at depths from approximately 15 to 45 feet below the ground surface. A stiff, plastic clay to silty clay is present above the top of the aquifer.

  127. This comment has been noted.

  128. There are continuous layers beneath the site.

  129. It is agreed that the layers beneath the site are continuous, however, they are not continuous layers of soil. The are alternating clay, sandy clay, and sandy soil.

  130. The final version, which includes LDEQ requested revisions, of the Remedial Investigation Summary Report is dated June 7, 1995, not August 30, 1994. Additionally, the following report should be added: Indoor Air Screening Report, LAW Environmental, Inc., November 1993. This report is Volume VI of the RI report dated June 7, 1995.

  131. The date has been modified.

  132. The benzene concentrations to which the draft PHA is referring are the same unvalidated data that are noted as being of questionable quality in the draft PHA on page B-15. The draft PHA should not use unvalidated data to draw conclusions about potential health impacts or to classify sites in public health assessments.

  133. This comment has been noted.

  134. The extensive body of validated data available is sufficient to show that there is no correlation between soil gas composition and indoor air composition at the Site.

  135. The composition of soil gas may be a factor in many indoor air problems existing at this site. Cracks in slabs as well as seepages may contribute to the indoor air contamination existing here.

  136. As stated earlier, many of the compounds cited are not associated with refinery operations. The extensive, prior work, conducted in accordance with LOPH- and LDEQ- approved sampling and analysis plans, is sufficient to show that the media cited are well characterized, and that the validated data clearly demonstrate that the site does not pose a health hazard.

  137. There are in fact many compounds present at this site that may not be associated with refinery operations. There has been extensive work done at the site, but the site is classified a public health hazard for the reasons stated in the conclusions section of the draft PHA.

  138. Some unvalidated, screening data obtained in earlier studies were performed at higher detection limits. However, the extensive subsequent , validated data, using EPA approved protocols such as TO-14, are more than sufficient to determine exposure and to determine reasonable maximum exposures and conclude that no health hazards exist at this site.

  139. This comment has been noted.

  140. There is no correlation between odors and health effects, so anecdotes about odors have little bearing on an objective health assessment. In addition, anecdotes of odors reported in the 1980's cannot be investigated in the 1990's. There have been no odor complaints reported in the recent past, and there is no indication that any odors relate to historic refinery operations as opposed to current land uses.

  141. This comment has been noted.

  142. As previously discussed, the frequency of sampling, the number of samples and the occurrence of sampling over a period of years shows that the indoor air is well characterized by the extensive validated data which included 24-hour sampling events.

  143. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  144. This statement is inaccurate "The sampling methods used for methane monitoring cannot determine if indoor methane levels fluctuate up to possible explosive levels"! The sampling methods used for methane monitoring, previously approved by LOPH and LDEQ, not only were sufficient to determine fluctuations in methane levels but also to prove that no indoor air concentrations of methane have ever even approached the LEL for methane. Even the substantial body of screening data available for the Site are sufficient to make this determination. There are absolutely no data to support the draft PHA's speculation about possible explosive levels. Generating groundless concerns through such speculation is not in the best interests of public health at the site and does not comport with the ATSDR Guidance Manual.

  145. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  146. These concerns (methane) were addressed in the Baseline Risk Assessment and not shown to present a hazard to public health.

  147. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  148. Since indoor air has already been extensively characterized with the work cited in the draft PHA, this recommendation (sampling for targeted soil gas contaminants) has also been fulfilled and should be deleted.

  149. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  150. As discussed earlier, methane levels have been monitored not only for months, but even for years and all of the indoor air results show that there is no realistic fire and explosion risk related to the Site. This recommendation is based upon speculation, not the extensive sampling data and should be deleted.

  151. This issue along with many other issues regarding air sampling, soil gas sampling and the data, will be addressed in a separate document.

  152. See Revised Table 1 for a more accurate and complete listing of the data (Refer to Page B-4, Table 1).

  153. The appropriate changes to the table have been made.

  154. This table (Page B-5, Table 2) did not include the trip blank data which is critical to an evaluation of the significance of the results shown in the table.

  155. This comment has been noted. The trip blank data indicates that BTEX compounds were not detected.

  156. As discussed earlier, odors do not cause health effects. This Public Health Assessment should address potential health effects.

  157. There are some compounds, often those containing sulfur, which can be detected at very low concentrations by the human nose. At the low levels at which the nose registers the odor, there are no measurable adverse health effects. These odors can however be unpleasant and can trigger headache or nausea. Some states have implemented 'nuisance" or 'quality of life' ambient air standards for hydrogen sulfide, mainly in response to the presence large-scale industrialized livestock facilities. Complaints of odor are not automatically dismissed in the Public Health Assessment process.

  158. As discussed earlier, indoor air at the site has been extensively and sufficiently characterized.

  159. This comment has been noted.

  160. As discussed earlier, detection limits in the extensive validated sampling programs were adequate to determine potential health effects at the site. The draft PHA itself points out that the "comparison values" are simply screening values and exceeding the "comparison value" does not establish a health risk.

  161. This comment has been noted, and the draft PHA asserts that comparison values do not establish the presence of a health risk.

  162. As discussed earlier, the draft PHA presents no rationale for any further evaluation of anecdotal data complaints. Sources of odors reported in the 1980's are no longer verifiable and odors do not cause health effects. Constituents of potential concern were selected with the approval of LDEQ and LOPH.

  163. This comment has been noted, please refer to the above stated comments regarding odors at this site.

  164. The statement of Page B-6 is incorrect. Two samples were collected in the breathing zone.

  165. In addition to the samples taken from under sinks and inside cabinets, samples were taken from the breathing zone.

  166. The reported highest total hydrocarbon values are not familiar to OXY and not found in the documents made available to OXY. The significance of these calculated confidence levels is not clear since the draft PHA does not mention them again.

  167. This comment has been noted.

  168. The levels of methane reported as "...in apartment 505..." were actually taken from beneath the slab of Building 5, not in an apartment. No such levels of methane have ever been observed in any building at the site.

  169. This comment has been noted.

  170. Pages B-6 and B-7 are examples of unvalidated data and further makes the point that only validated data should be used in the PHA.

  171. This comment has been noted.

  172. See attached Revised Table 3 for a more accurate and complete listing of the data.

  173. The table was revised to show that the unknown samples were taken under the kitchen sink in Alexis Park Apartment #1905.

  174. The sentences on Page B-9 should be revised.

  175. The necessary corrections have been made.

  176. The extremely frequent sampling under the LOPH- and LDEQ-approved sampling plans shows that methane levels in indoor air never reached even 25% of the LEL for methane, and that no explosion hazard exists. Since the extensive data show this conclusively and without exception, speculation about what "might have been" is unjustified.

  177. This comment has been noted.

  178. Unvalidated data should be used only for screening and should not be used when validated data are available. The data that are the subject of the comments in the draft PHA were not validated. Therefore, they were not used in OXY's Baseline Risk Assessment, and, in keeping with ATSDR's own Guidance Manual, should not be used in health assessments for the same reason.

  179. This comment has been noted.

  180. The executive summary of the August 15, 1990 Indoor Air Monitoring Report that was prepared by ERM-Southwest, Inc. does not make this statement "Although the report summary indicates that all samples were analyzed for BTEX and hydrocarbons, many samples were analyzed for benzene only.".

    This comment has been noted.

  181. As discussed earlier, it is not possible in 1996 to identify the sources of odors in the 1980's, although there is no reason to conclude that historic refinery operations relate to odor complaints. Moreover, odors are not health hazards and are not germane to the health assessment of this site.

  182. This comment has been noted.

  183. As discussed earlier, and stated in the draft PHA itself, exceedence of a "screening level"is not in itself , an indication of health risk. The extensive, validated data used in the Baseline Risk Assessment demonstrate that the site does not pose a health hazard.
    It is never implied in the draft PHA that screening levels imply health risks, and this comment is noted.

  184. This table (Page B-10, Table 3) contains screening data which has been supplanted by the subsequent extensive body of validated data.

  185. Your comment has been noted, however, at the time that this document was written, the screening data was all that existed.

  186. These samples (Page B-12, Table 5) are not "Unidentified" and the materials supplied by OXY to ATSDR and LOPH show this. None of the samples identified in this table were collected from indoor air in any building.
    The unidentified samples were collected from soil gas adjacent to Alexis Park Apartments.

  187. These samples (Page B-13, Table 6) are also not "Unidentified". None of the samples identified in this table were collected from indoor air in any building.
    Refer to Comment #112.

  188. We agree with the draft PHA conclusion that such unvalidated information is suspect and should not be used or relied upon in an assessment of potential health risks or impacts. These data have been previously determined to be unusable by the LDEQ due to coelution of other compounds.
    This comment has been noted.

  189. The available documentation on some of these LDEQ sampling events is of poor quality (i.e. no chain of custody, no sample location information, presence of household chemicals, etc.). The limitations of these data are discussed on page B-15 of the draft PHA.
    This comment has been noted.

  190. The table on page B-15 #8, should be corrected.
    The appropriate changes have been made.

  191. Any sample or sampling event for which the data cannot be validated should be rejected and not used in the health assessment. Since the draft PHA expresses concern about the validity of these samples, the entire sampling event should be rejected and ignored in the health assessment.
    This comment has been noted.

  192. The statement regarding indoor air (reported January 1993) page B-16, is not accurate and should be corrected.
    The statement is accurate; the PRP would like the details listed, and those are available upon reviewing the various references.

  193. The statement regarding the frequency of indoor air screening on page B-16, illustrates the extensive nature, frequency, and duration of the indoor air screening program. When combined with the subsequent validated data it shows that no further sampling is necessary.
    This comment has been noted.

  194. Because of the screening nature of the November 1993 sampling event, none of these screening data were used in the Baseline Risk Assessment to evaluate potential exposure scenarios and potential health effects that might occur. The PHA should also not rely on screening data for health evaluation of the site.
    As the original statement in the draft PHA says, "The results of screening tests are helpful for determining future sampling locations where more thorough analysis of contaminants will be done but, is not useful in evaluation of exposure and health risks at the site."

  195. The assertion regarding the sampling schedule on page B-16 is unjustified and does not take into account the extensive, data available to investigators. This LOPH- and LDEQ- approved sampling schedule was indeed, sufficient to evaluate hydrocarbon levels including any fluctuations.
    This comment has been noted.

  196. The description regarding the Indoor Air Monitoring Report, referred to on page B-16, is incomplete.

  197. This comment has been noted. Not only should the supplement to the work plan be listed, but the subsequent supplement as well as the initial work plan itself.

  198. The original wording of this statement "The purpose of the sampling was to determine airborne concentrations of selected hydrocarbons in indoor areas on portions of the site." was more accurate; As stated on Page 1 of the LAW Indoor Air Monitoring and Analysis report (Attachment 32), "This investigation focused on areas of the site where the presence of indoor airborne hydrocarbons has been documented."

  199. This comment has been noted.

  200. The statement on page B-17 is incorrect. Actually 14 concurrent samples were collected from inside wall and floor air space.

  201. This comment has been noted.

  202. The subject report does not make a statement regarding 36 sampling locations and their basis.

  203. This comment has been noted.

  204. The source of the following statement "The rationale for choosing sampling locations was presented as follows:' is not clearly identified.

  205. This comment is noted.

  206. To be more complete the following sentence should be added to page B-17. "The two additional locations were approved by the LDEQ".

  207. This comment has been noted.

  208. The statement regarding Alexis Park, Apartment #501 on page B-17, is not correct. Alexis Park Apartment 501 and the Carriage Square unit at 200 Napoleon have both been sampled several times, including in both the 1993 LDEQ sampling event and the LAW 1994 sampling event.
    This comment is noted, Alexis Park #501 was not the only unit to be sampled more than once, Carriage Square #200 has been sampled more than once as well.

  209. The statement regarding ranking on page B-17, is not correct. In fact, the "ranking" has no bearing on the likelihood of contamination. The location that exhibited the highest FID readings was ranked number 1, the second highest number 2, and so on.

  210. The statement is correct. The ranking has no bearing on the likelihood of contamination, but is, in fact, a direct indicator of the level of contamination when compared with other areas being sampled during the same event.

  211. Table 9 on page B-19 should be revised.

  212. This table has been revised.

  213. As specified in the LOPH- and LDEQ- approved sampling and analysis plans, each indoor air sample was analyzed for 13 volatile constituents and one semivolatile constituent (napthalene). This list of compounds was selected to include constituents often associated with refinery operations and/or petroleum storage and handling facilities. And those with the greatest potential to cause health effects.

  214. This comment regarding the statement of pages B-19 & B-20 has been noted.

  215. Since concentrations of constituents of concern in breathing zone samples are more relevant to evaluate possible health effects than are samples from inside walls, a larger number of breathing zone samples were taken to assess the potential health effects, if any. Approximately 1/3 of the units were also sampled inside the walls for comparison to the detected concentrations in the breathing zone.

  216. This is the response to the question of why breathing zone samples were taken in 36 dwellings, versus the inside wall sampling of only 13 of these dwellings referred to on page B-20.

  217. The statement on page B-20 is correct. Since the low concentrations of constituents found do not present a health hazard (as shown by the extensive amount of validated data), the sources of odors are irrelevant to the health assessment. Odor thresholds are similar to CREGs or other comparison values - they serve to indicate further work should be done but, once the validated work is done, they should be ignored in evaluating potential health risks or impacts.

  218. This comment has been noted.

  219. The 1993 data are the very same unvalidated results that have been discussed earlier. They cannot be compared to subsequent validated data nor used to reject conclusions about potential health risks or impacts based upon the validated data.

  220. This comment has been noted, and reference may be made to all other responses regarding the use of unvalidated data.

  221. The statement on page B-20 regarding a summary report of soil gas and indoor air sampling is incorrect.

  222. The statement is not incorrect. It does not in great detail list everything the summary report contains, but it is a summary report regarding soil gas and indoor air sampling.

  223. This statement regarding FID readings on page B-20 is misleading. Field measurements were not made at each location. As stated in the ETI report "a detailed sampling grid containing 30 to 100 foot centers was utilized in areas containing significant concentrations of hydrocarbons vapors detected during the execution of the regional study.

  224. This comment has been noted.

  225. This statement on page B-20 regarding 896 samples is incorrect. 898 samples were collected.

  226. The number has been changed to 898.

  227. Field FID measurements were not made at each location. To clarify the sentence it should be related as follows: "Soil gas samples were taken (placed into evacuated 125 ml vials) from a specially designed soil vapor probe which was inserted into each pre-driven seven foot sampling hole"

  228. This comment has been noted.

  229. In the notes section of the table the total number of samples should be 898 instead of 896.

  230. The number has been changed to 898.

  231. There were actually 7 different events.

  232. The text has been modified to reflect 7 sampling events.

  233. As identified above, there were 7 sampling episodes.

  234. Please refer to question 140.

  235. We agree that these unvalidated data should not be used or relied upon in any way. These data were not used in the Baseline Risk Assessment.
    This comment has been noted.

  236. This report should be numbered (11) instead of (10), and the final version is dated June 7, 1995, not August 30, 1994.
    The repot is numbered correctly, however, the date has been changed.

  237. This statement is incomplete and explains why the draft PHA erroneously states that tars were not analyzed for metals. Each of the 3 tar samples were analyzed for TCL-semi-volatiles and arsenic, barium, lead, and mercury (Attachment 52).

  238. The samples may have been analyzed for metals, however, poor data quality resulted in no concentrations of metals being found.

  239. As noted above, this statement is inaccurate. Additional tar samples were also collected and split with EPA during the June 29, 1995 sampling event. These samples were analyzed for Target Compound List (TCL) volatiles, semivolatiles and lead. The results are provided in Attachment 52. In addition to the split samples collected on June 29, 1995, EPA unilaterally collected tar samples the previous month. OXY has requested a copy of EPA's data but has never received it.

  240. This comment has been noted.

  241. The title of the table should read: "1985-1987 Surface/subsurface soil/material sampling result summary" since the majority of the samples did not consist of tar-like material. See attached Revised Table 11 (Attachment 80) for a more complete and accurate listing of the data.
    Your comment has been noted, and readers may refer to the referenced documents to obtain the additional information.

  242. As noted above, this statement is inaccurate (page B-24). See revised Table 12, "Tarlike Material Sampling Results-August 11-12, 1992 Sampling" (Attachment 81). Total volatile hydrocarbons were measured with the FID in the borehole immediately after each tar-like material sample was collected.
    Please refer to Comment #145.

APPENDIX D

GLOSSARY/ACRONYMS

ATSDR
The Agency for Toxic Substances and Disease Registry. ATSDR is a federal health agency in Atlanta, Georgia that deals with hazardous substance and waste site issues. ATSDR gives people information about harmful chemicals in their environment and tells people how to protect themselves from coming into contact with chemicals.

CERCLA

The Comprehensive Environmental Response, Compensation, and Liability Act was put into place in 1980. It is also known as Superfund. This act concerns releases of hazardous substances into the environment, and the cleanup of these substances and hazardous waste sites. ATSDR was created by this act and is responsible for looking into the health issues related to hazardous waste sites.

Comparison Value (CVs)

Concentrations or the amount of substances in air, water, food, and soil that are unlikely, upon exposure, to cause adverse health effects. Comparison values are used by health assessors to select which substances and environmental media (air, water, food and soil) need additional evaluation while health concerns or effects are investigated. Also known as HAC (Health Assessment Comparison)Values.

CREG

The Cancer Risk Evaluation Guide is an estimated contaminant concentration that would result in no more than one excess cancer in a million (10E-6) persons exposed over a lifetime. CREGs are calculated from USEPA's cancer slope factors (CSFs).

EMEG

Environmental Media Evaluation Guides are based on ATSDR's minimal risk levels (MRLs). An MRL is an estimate of a daily human exposure to a chemical that is likely to be without an appreciable risk for noncarcinogenic effects over a specified duration of exposure (acute, intermediate, chronic).

LDEQ

Louisiana Department of Environmental Quality

LDHH

Louisiana Department of Health & Hospitals

LTHA

The Lifetime Health Advisory represents a contaminant concentration that USEPA considers to be protective of noncarcinogenic health effects during a lifetime (70 years) of exposure.

LTR

Louisiana Tumor Registry

MRL

Minimal Risk Level. An estimate of daily human exposure - by a specified route and length of time -- to a dose of chemical that is likely to be without a measurable risk of adverse, noncancerous effects. An MRL should not be used as a predictor of adverse health effects.

NPL

The National Priorities List. (Which is part of Superfund.) A list kept by the U.S. Environmental Protection Agency (EPA) of the most serious, uncontrolled or abandoned hazardous waste sites in the country. An NPL site needs to be cleaned up or is being looked at to see if people can be exposed to chemicals from the site.

OPH

Office of Public Health

PAH

Polycyclic aromatic hydrocarbons

PCP

Pentachlorophenol

PELs

Permissible Exposure Levels

PHA

Public Health Assessment. A report or document that looks at chemicals at a hazardous waste site and tells if people could be harmed from coming into contact with those chemicals. The PHA also tells if possible further public health actions are needed.

PNAs

Poly Nuclear Aromatics

ppb

Parts Per Billion

ppm

Parts Per Million

PRP

Potentially Responsible Party. A company, government or person that is responsible for causing the pollution at a hazardous waste site. PRP's are expected to help pay for the clean up of a site.

Reference Dose (RfD)

An estimate, with safety factors (see safety factor) built in, of the daily, life-time exposure of human populations to a possible hazard that is not likely to cause harm to the person.

RMEG

Similar to the EMEG but derived from USEPA's reference dose. It is the concentration in a specific media at which daily human exposure is unlikely to result in adverse noncancerous effects.

SEET

Section of Environmental Epidemiology & Toxicology

SIR

Standard Incidence Ratio

SLU

Southeastern Louisiana University

U.S. Environmental Protection Agency (EPA)
:
The federal agency that develops and enforces environmental laws to protect the environment and the public's health.

VOCs

Volatile Organic Compounds

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