Class I Mechanical Integrity 


Failure Analysis (1993-1998) 


prepared for: 

u.s. Environmental Protection Agency 

Office of Ground Water and Drinking Water 

Underground Injection Control Program 

Principal Investigator: 

Larry Browning 

Project Manager: 

Steve Wyngarden 


Contract No. 68-C6-0029 


Work Assignment No. 11 


September 30, 1998 

Class I Ml Fqilure Analysis 0993-1998) 1 

Executive Summary 

We studied workover and mechanical integrity test (MIT) records of 541 Class I wells 

in 13 states, for the period February 1993 to July 1998. These 13 states were 

selected to track with the states examined in a similar study performed for the period 

1988-1993. This sample includes 100 percent of the Class I Hazardous waste 

injection wells and 85 percent of the Class I Non-hazardous waste injection wells 

active in the U. S. since 1993. 

We found 129 certain internal MI failures, and 19 probable MI failures. The internal 

MI failures were detected immediately by the continuous annulus monitoring system 

required of Class I wells, and the wells were usually shut-in until operators could make 

repairs. 

In all states except Texas, the incidence of MI failures in Class I wells was found to 

decrease by about half, when compared to the previous 5-year study period (the ratio 

of well failures to active wells was 18 percent between 1993-1998 versus 33 percent 

between 1988-1993). In Texas, MI failures from 1993-1998 were found to triple 

compared to the previous study (96 MI failures/well failure to active well ratio of 89 

percent, versus 45 failures/well failure to active well ratio of 31 percent from 1988­

1993). Furthermore, the severity of MI failures in Texas (as denoted by incidence of 

long-string casing failure) was found to also triple (38 cases/66 percent of certain MI 

failures, versus 8 cases/18 percent of failures for the previous study). Over the 5-year 

study period, Class I Non-hazardous waste wells in all states except Texas were found 

to fail three-times less often than Class I Hazardous waste wells failed (13 percent for 

NHW versus 40 percent for HW, 1993-1998). In Texas, however, Class I Hazardous 

and Non-hazardous waste wells experienced MI failures at a similar (and much higher) 

rate (90 percent versus 87 percent). All of these percentages refer to the ratio of well 

failures to the number of active wells, not the fraction of wells that failed because 

many wells failed several times. 

We worked closely with staff in the Texas Underground Injection Control (UIC) 

Program to assemble and review the data on Class I well failures in Texas. We also 

sent the Texas UIC staff a draft version of the compiled data and results for that state 

in an effort to ensure completeness and accuracy. However, recognizing the 

substantial differences between the results for Texas and the rest of the nation, we 

recommend that this report be reviewed by staff in Texas and EPA Region 6 to confirm 

these results and, if necessary, provide additional data and analysis. 
Cklss I Ml Failure Analysis U993-19981 2 

We found 11 external MI failures. We also investigated 27 cases of significant waste 


migration out of the injection zone. Four cases of waste migration are known to have 


affected an Underground Source of Drinking Water or USDW (3 in Florida and 1 in 


Texas '), eight cases are suspected to affect a USDW (Florida), 15 cases involved 


migration from the injection zone into permitted (3) or unpermitted (12) saline zones 


(7 Florida, 1 Ohio, and 7 Texas), and five cases of suspected migration remain 


unknown as to extent (Texas). Eleven external MI failures and 26 migration cases 


were detected by routine periodic external MITs (every five years) or by periodic 


sampling of state-mandated deep monitoring wells. Five of the waste migration 


. incidents, however, were attributable to external or internal MI failures of monitoring 


wells at the site. 

ITbe Texas case (WDW-117, Jetco Chemicals) did not involve migration. Rather, in 1974 and 1990 

the Texas VIC primacy agency permitted a Class I well to inject directly into a VSDW (about 5,000 mgtl 

total dissolved solids). The well permit was canceled in May 1994 when the error was discovered after 

20 years' injection (and about 1.6 billion gallons). The injection zone is a drinking water source in 

adjacent counties. 
Class 1M! Failure Analysis a993-19981 3 

1.0 Background 

The purpose of this report is to assess the number of, reasons for, and responses to 

Class I injection well MI failures that occurred from February 1993 through July 1998. 

Class I injection wells are regulated according to the nature of the injectate, whether 

Hazardous waste (Haz or HW) or Non-hazardous waste (Non-haz or NHW). We include 

in this study 100 percent of the Class I HW wells and 85 percent of the Class I NHW 

wells active in the US since 1993.2 We directly examined and interpreted Class I well 

records for Texas and Louisiana (48 percent of all Class I wells and 70 percent of 

Class I Hazardous wells), and primacy agencies and EPA Regions 4 and 5 supplied us 

with well records and data concerning the other states (FL, KY, TN, MS, IN, IL, MI, 

OH, AR, OK, and KS) (Table 1). 

This study is a follow-on to a similar study performed for the period January 1988 

through January 1993, and utilizes the same methods and assumptions. 

2.0 Class I construction elements and failures 

All Class I HW wells are newly drilled for dedicated disposal service, rather than being 

converted from oil and gas wells or wells in other service. A few Class I NHW wells 

are conversions of existing wells, and the conversion must meet the same construction 

standards as newly drilled wells. Mechanical integrity (M!) of a Class I well consists 

of two types: internal MI is the absence of leaks in the tubular goods of the well, 

whereas external MI is the absence of flow along the outside of the casing (i.e., the 

integrity of the cement seal). Class I wells are required to maintain mechanical 

integrity (M!) at all times. We define an "MI failure" of a Class I well as any loss of 

mechanical integrity, whether discovered in an MI test (MIT) or during operational 

service. 

The program of construction and testing of a Class I well is specified by the UIC 

Director as a permit condition. The process of drilling and construction is sometimes 

witnessed by a representative of the UIC agency. The key construction elements of 

a Class I well (Figure 1) are: 

2Inventory totals are for "Active" wells in Injection Well Inventory FY 1997, V.S. EPA VIC Program, 

Office of Ground Water and Drinking Water (August 1997), or were specified (as noted) by primacy 

agencies. 
Class I Ml Failure Analvsis (] 993-19981 4 

Figure 1: Components of a Typical Class I Well 


Cement ~ 

Base of 10,000 mgll TOS US OW 

~IE-- Surface Casing 

,.-- Long String Casing 

Annulus -~~ 

Injection Tubing 

~:: :~.:::~ 

~ 

ir J~ 

Confining X ...IF..f--lnjection Packer Zone 

... 

------------~~ . 

_S ../'-... ~ --"'r=~

Injection Zone ------.'"" r-'" .? :'.~ 

":. ::~. 

~_l_'_____J 
Class I MI Failure Analysis 0993-19981 5 

A. Surface casing 

This "string" of pipe is the outermost of the three concentric layers of protection 

of a Class I well (surface and long-string casing, and tubing). Typically sized from 

7 Y2 to 10 3/4 inches diameter, this carbon steel casing extends from the surface 

to below the lowermost USDW having at least 10,000 mg/I total dissolved solids 

(TDS) content, and is cemented fully to the surface. The purpose of cement is to 

completely seal the casing to the borehole wall, in order to prevent external fluid 

movement (outside the casing) and corrosion. Because surface casing is installed 

as one of the first steps in the construction process, it also protects USDWs from 

the effects of drilling. 

The quality of the casing and the effectiveness of the cement seal is carefully 

tested and approved by the Director before drilling can continue. However, the 

integrity of surface casing cannot be tested during operation, and failure analysis 

of surface casing is not possible. 

B. Long-string casing 

Long-string casing extends from the surface to or through the injection zone. 

Typically from 4 Y2 to 8 5/8 inches in diameter, long-string casing is either 

perforated or terminates in a screen assembly to facilitate the passage of waste 

from the well bore into the formation. Most long-string casing is carbon steel, 

although a variety of corrosion-resistant materials may be used for casing (e.g., 

stainless and High-Nickel alloys, or fiberglass-reinforced plastic). Long-string caSing 

is usually cemented along its entire length, to prevent external fluid movement and 

corrosion. 

The condition of casing and the effectiveness of the cement seal are tested by the 

operator3 before authorization to inject is given. The absence of leaks in this casing 

is continuously monitored in Class I wells (see annulus, below), and the condition 

of the casing and cement seal are tested downhole every five years. 

c. Injection tubing 

Tubing is the innermost element of the well (2 Y2 to 7 inches diameter), and 

conducts the waste from the surface to the injection zone. Because it is in 

3Many of these tests are witnessed by state or Regional VIC staff. 
Class T Ml Failure Analvsis 0993-/9981 6 

continuous contact with the waste, tubing frequently utilizes corrosion-resistant 

design and materials (coatings or linings, or construction of fiberglass-reinforced 

plastic), However corrosion-proof the material may be, tubing must have threaded 

joints to allow it to be installed in the well, Because a well may contain as many 

as 600 tubing unions, these threads may develop minor leaks from time to time. 

The MI of the tubing is assured before injection begins, and is monitored 

continuously during operation. Tubing is usually pulled from the well at least every 

five years and tested and inspected at the surface. 

D. Packer annulus 

This mechanical device seals the outside diameter of the tubing to the inside 

diameter of the long-string casing. This device may consist of a simple, mechanically set rubber element, or a complex, concentric-seal assembly tens of feet long 

and constructed of corrosion-resistant materials. The purpose of the device is to 

isolate the casing from injected waste and create a fluid-tight seal of the tubingcasing annular space (sealed at the surface by the wellhead), allowing a constant 

pressure to be maintained on the annulus. Continuous monitoring of this pressure 

allows a direct indication of the internal MI of the well at all times. Periodically 

(once per year for HW wells, once per five years for NHW wells), the operator is 

required to conduct a distinct pressure test of the well annulus, and to inspect the 

continuous monitoring system. Annulus tests and continuous monitoring data are 

reported to the UIC agency on a quarterly basis. 

Each of the components of a Class I well can fail due to corrosion, manufacturing 

defects, improper installation, or mechanical damage during construction or operation. 

The operator of every Class I HW well is required to conduct continuous monitoring 

of the annulus pressure, and all HW (and many NHW) well monitoring systems are also 

connected to an auto-shutdown system, so that in the event of a loss of MI the 

operator is immediately alerted and injection automatically ceases. The operator is 

required to notify the State UIC Director within 24 hours of a loss of MI or shutdown, 

and shut in the well until repairs are completed and approved. 

Because MI is monitored continuously in Class I wells, there are very few formal MIT 

failures for Class I wells, compared to losses of MI in service discovered immediately 

by the monitoring system. For this study, we analyzed not only MIT records but also 

records of well workovers. For example, from 1988 to 1993 in Louisiana, the 

Department of Natural Resources recorded only two formal MIT failures of Class I 
C/gss l Ml Failure Analvsis U993-19981 7 

wells, whereas Class I operators performed 38 workovers to repair losses of MI in 

service. 

We grouped component failures as to tubing, packer, casing, wellhead, or, when 

detailed information was not available, non-specific annulus leaks. In response to a 

failure, the entire tubing string may be replaced, or only a few individual "joints" 

(which implies a minor defect). Similarly, packers may be replaced, or only re-set. 

Casing may be repaired by installation of a Iiner, 4 squeeze-cementing,5 plugback,6 or 

sidetracking7 (which imply progressively more serious casing problems). 

3.0 Internal MI Failure 

We found 129 certain internal MI failures of 541 Class I wells that were active at 

some time from February 1993 to July 1998 (Table 1). There were also 19 additional, 

probable MI failures in Texas, for which we lack complete data (these 19 probable MI 

failures are considered in calculations only where noted). 8 A statistical projection of 

the probability of MI failure of an individual well is not valid, because many wells failed 

4A liner is another string of casing (either full-length or partial) installed within the existing long-string 

casing, either hung with a seal assembly or cemented in place. 

5 A squeeze is a remedial procedure where the casing is perforated and cement is forced outside the 

casing. This technique is capable of repairing both internal casing leaks and external fluid-movement 

problems. 

6A plugback is a repair procedure for a casing failure within the permitted injection interval. The well 

is repaired by cementing inside the casing from the bottom of the well to above the location of the casing 

leak. The casing is then re-perforated, and injection continued into a higher zone in the permitted interval. 

7This technique involves plugging back the well to some interval above the casing problem, and cutting 

a window in casing to allow directionally drilling a divergent, duplicate lower section of the well at an 

angle to the original, completed in the same or another zone of the permitted interval. 

8Probable cases involved references in correspondence to MI-type workover operations (e.g., squeezecementing or replacing a tubing string), but which contained no specific reference to loss of MI and/or 

details of the procedure. Some references were fairly definite but not positive, whereas most indicated only 

that replacement of MI-related components took place. We also used probable failures for the 1993 study, 

but because they were fewer we counted them in all calculations. 
Class l MI Failure Analvsis (J 993-19981 8 

Table 1 


Class I Inventory and MI Failure Incidence (1993-1998) 


Wells MI Failures 

Haz Non-haz Haz Non-haz 

Florida 1 129 0 3' 


Mississippi 2 5 3 0 


Indiana 4 7 2 1 


Illinois 6 0 1 0 


Michigan 9 13 2 9 


Ohio 10 3 12 1 

Arkansas 6 10 1 5 

Louisiana 17 25 12 10 

Oklahoma 0 11 0 0 

443 273 Texas 70 38 


Kansas ...5. .6.1 ..2 ...5. 


Total 130 302 68 61 

Does not include 4 external MI failures and 17 incidents of migration. 

Does not include 1 external MI failure and 1 incident of migration. 

3 Does not include 19 probable MI failures, six external MI failures, and eight 

incidents of migration. 

Source: Appendix A 
Class I MI Failure Analysis (]993-J998/ 9 

several times during the study period, and others not at all (Appendix A).9 In addition, 

Class I wells were plugged and Temporarily Abandoned during the study period at a 

higher rate than new wells were drilled, and states varied in the rates that Class I wells 

were added or subtracted from their inventory. In order to present comparative 

estimates (for information only), we base our rate estimates (percent) on the number 

of Class I wells active in each state in 1998. 

Nationally, we found that 432 active Class I wells experienced 129 certain internal MI 

failures between February 1993 and July 1998 (a ratio of well failures to active wells 

of 30 percent). We found that Class I wells in Texas experienced MI failure at a much 

higher rate (a well failure to active well ratio of 66 percent or 83 percent including 

probable failures) (Table 1). Due to the contradictory nature of our findings, we 

present separate discussions for results observed in 12 states (Florida, Kentucky, 

Tennessee, Mississippi, Indiana, Illinois, Michigan, Ohio, Arkansas, Louisiana, 

Oklahoma, and Kansas), and for results observed in Texas. 

3.1 All States except Texas 

We found that 324 active Class I wells'o experienced 58 internal MI failures between 

1993 and 1 998 (1 8 percent). Probably due to the corrosive nature of many hazardous 

wastes, 60 active Class I HW wells experienced 24 internal MI failures (40 percent), 

a rate three times greater than that of NHW wells (13 percent; 264 NHW wells with 

34 failures) (Table 1). 

In these states, 78 percent of Class I internal MI failures involved tubing, packer, or 

wellhead. Twenty percent of internal MI failures involved long-string casing (Table 2). 

Because it represents the outermost layer of protection capable of MI, long-string 

casing failures were judged more serious. In contrast, a 1993 study of Class II (oilrelated) MI failures showed that about 50 percent of Class II MI failures involved longstring casing." The long-string casing in Class II wells is not usually fully cemented, 

9About 329 Class I wells did not experience MI failure during the study period. A total of 103 wells 

failed 154 times: 34 wells failed more than once during the study period (Feb 1993 through July 1998), 

one lost MI 6 times, two lost MI 4 times, nine lost MI 3 times, and 22 failed twice. Similar results were 

found for the period 1988-1993. 

10About 396 Class I wells were active at some time during the study period. 

11Analysis of the rate ofand reasons for {Class II] injection well Mechanical Integrity test failures, L. 

Browning and J.D. Smith, Society of Petro Ieurn Engineers Paper No. 25967 (August 1993). 
Class TMl Failure Analysis 0993-/998) 	 10 

and is subject to corrosion from saline formation fluids. Most Class I wells in these 

states feature fully cemented casing, and this requirement may explain the lower 

incidence of casing failure observed in these Class I wells. 

3.2 	Texas 

We found in Texas that 108 active Class I wells experienced 71 certain and 19 

probable internal MI failures between 1993 and 1998 (well failure to active well ratio 

of 66 percent for certain failures, 83 percent including probable). Unlike all other 

states, NHW wells were found to experience a similar rate of internal MI failure as HW 

wells (71 percent NHW versus 63 percent HW for certain MI failures,' or 82 percent 

NHW184 percent HW including probable) 12 (Table 1). 

In Texas, 66 percent of internal MI failures with known reasons involved long-string 

casing, compared to 20 percent in all other states (Table 2). This incidence of casing 

failure is more characteristic of Class II wells, which do not usually feature fully 

cemented casing. 13 An EPA Region 6 study of Class I wells in Texas found that many 

Texas Class I HW wells do not feature complete cement as per UIC regulation. For the 

Class I wells that had cementing data, Region 6 found that: 

1. 	 90 percent of Texas Class I wells did not have long-string cement to surface; 

2. 	 30 percent of Texas Class I wells did not have cement that extended even 

to the bottom of surface casing; and 

3. 	 44 percent had major cement problems over hundreds or thousands of feet 

of long-string casing, and that up to 22 percent featured absent to poor 

cement bond overall. 14 

12Por certain MI failures, 38 NHW wells experienced 27 MI failures between 2/93-7/98 (71 percent) 

versus 70 HW wells experienced 44 MI failures (63 percent). Por probable failures, 38 NHW wells/31 

failures (82 percent) versus 70 HW wells/59 failures (84 percent). These values do not include six (4/2) 

external MI failures. 

13Analysis of the rate ofand reasons for [Class II] injection well Mechanical Integrity test failures, L. 

Browning and J.D. Smith, Society of Petroleum Engineers Paper No. 25967 (August 1993). 

14External Mechanical Integrity Log Interpretations for Class I Wells in Texas, prepared for EPA 

Region 6 by The Cadmus Group (September 30, 1993). 
Clgss T Ml Failure Analysis a993-19281 11 

Table 2 

Types and Incidence of Class I Internal MI Failures (1993-1998) 

All States (except Texas) 

Tubing 

Packer 

Wellhead 

Casing 

Unspecified 

Total (non-TX) 

J:iaz 

14 

3 

0 

5 

2 

24 

3/2. 

64% 

14% 

22% 

40% 

NHW 

14 

11 

2 

6 

1 

34 

~ 

42% 

33% 

6% 

18% . 

13% 

Total 

28 

14 

2 

11 

3 

58 

% 

51 % 

25% 

4% 

20% 

18% 

Texas 

Tubing 

Packer 

Wellhead 

Casing 

Unspecified 

Total (Texas) 1 

~ 

9 

4 

0 

20 

11 

44 

3/2. 

27% 

12% 

61% 

63% 

NHW 

5 

2 

0 

18 

2 

27 

~ 

20% 

8% 

72% 

71 % 

IQl.al 

14 

6 

0 

38 

13 

71 

3/2. 

24% 

10% 

66% 

66% 

Does not include 19 probable and 6 external MI failures. 

EPA Region 6 suggested that the problems with cement coverage of Texas Class I 

wells might stem from the unconsolidated nature of Gulf Coast sediments, which could 

present speCial problems for operators in the process of well cementing. Class I 

operators in Louisiana, however, encounter the same cementing problems as do 
Class T MT Failure Analysis a993-19981 12 

operators in coastal 15 Texas. We performed the identical search of Class I files in 

Louisiana as Texas, and found that casing failures in Louisiana account for only 18 

percent of MI failures (for both HW and NHW wells), the same percentage found for 

all other states (Appendix A). For these reasons, we believe that external cement 

coverage, rather than waste corrosivity, is the more likely reason for long-string casing 

failure in Texas Class I wells. 

• 	 Because high or low pH makes for characteristic hazardous waste, HW injectate is 

often far more corrosive than NHW industrial waste. Class I HW wells in Texas, 

however, experienced a lower incidence of casing failure than NHW wells (61 

percent of MI failures with known reasons versus 72 percent for NHW wells). In 

our examination of Texas Class I files, we found that some Class I NHW wells are 

conversions of oil wells and tests, and that many NHW wells feature less cement 

coverage of long-string casing than HW wells. 

• 	 In our examination of Louisiana Class I files, we found that although similar 

corrosive wastes are injected, Louisiana HW wells generally feature more extensive 

cement coverage than do Texas Class I wells. Louisiana's HW experience also 

suggests that cement coverage, rather than waste corrosivity, may be the reason 

for 72 percent fewer casing failures found there (and in all other states) than in 

Texas. 

4.0 External MI and Migration 

External MI failure usually involves either improper installation of cement outside the 

long-string casing, or failure of cement due to corrosive dissolution or fracturing. 

Migration of wastes from the injection zone can occur either along casing (due to 

external MI failure), or can occur at some distance from the wellbore. The possibility 

for USDW contamination due to uniform upward seepage of wastes is extremely 

remote in most areas, due to alternating layers of permeable and impermeable 

formations that are present to contain the waste. 16 Of greater concern is the presence 

of natural or man-made conduits that may allow a direct pathway for injected waste 

or displaced saline formation fluids to contaminate USDWs. Conduits include natural 

15Actually, about 1/3 of Texas Class I wells are in non-coastal "hard-rock country" such as west Texas. 

Casing failures, however, were found to occur about equally in both areas. 

16Ground water modeling studies performed in support of the Class I Regulatory Negotiation 

Committee, U.S. EPA (March 1987). 
Class I MI Failure Analysis U993-19981 13 

fractures or transmissive faults, man-made hydraulic fractures due to excessive 

injection pressures, and unplugged or improperly sealed abandoned oil and gas wells. 

The primary objective of the No-Migration Petition process for Class I wells involves 

an analysis of the potential presence of both natural and man-made conduits. Where 

geologic conditions might permit the existence of natural fractures in the confining 

zone, or where alternating permeable/impermeable layers do not provide secondary 

containment in the event of migration, monitoring wells can be required. 

We found 11 external MI failures in Florida, Ohio, and Texas (Appendix A). We also 

investigated 27 cases of significant waste migration out of the injection zone. Four 

cases of waste migration are known to have affected a USDW (3 in Florida and 1 in 

Texas 17), eight cases are suspected to affect a USDW (Florida), 15 cases involved 

migration from the injection zone into permitted (3) or unpermitted (12) saline zones 

(7 Florida, 1 Ohio, and 7 Texas), and five cases of suspected migration remain 

unknown as to extent (Texas). 

The 11 external MI failures were detected by routine (5-year) external MIT. Migration 

incidents were detected by external MIT or by periodic sampling of state-mandated 

deep monitoring wells. Five of the waste migration incidents, however, were 

attributable to external or internal MI failures of monitoring wells (Florida). One of the 

migration incidents (into an unpermitted saline zone) was caused by an internal MI 

failure (Florida). 

Two-thirds of migration incidents occurred in Florida, and involved migration of Nonhazardous waste from the injection zone in areas of natural fracturing that may also 

lack alternating permeable and impermeable layers (Appendix A). These Class I wells 

inject Non-hazardous municipal sewage effluent, pre-treated to secondary standards 

and suitable for surface discharge. In each case, the UIC Director required deep 

monitoring wells as a permit condition. 18 The same geologie variability, however, that 

allowed minor waste migration from the injection zone allows communication of 

surface water with valuable shallow drinking water aquifers. On that basis, the UIC 

17The Texas case (WDW-117, Jetco Chemicals) did not involve migration. Rather, in 1974 and 1990 

the Texas VIC primacy agency permitted a Class I well to inject directly into a USDW (about 5,000 mgtl 

TDS). The well permit was canceled in May 1994 when the error was discovered after 20 years' injection 

(and about 1.6 billion gallons). The injection zone is a drinking water source in adjacent counties. 

18Four of the migration incidents were caused by internal and external MI failures of site monitoring 

wells. 
Class 1 Ml Failure Analysis U993-1998) 14 

Director made a resource-based decision that injection was preferred over surface 

discharge as a method of disposal. 

Most remaining incidents involved migration of wastes along casing, either into 

unpermitted saline zones or permitted "containment zones" provided in No-migration 

petitions and permits. These incidents were discovered by routine external MI testing. 

One incident involved Class I injection directly into a USDW in Texas. A Class I well 

at Jetco Chemical (Corsicana, Texas) was permitted by Texas UIC agencies in 1973 

and drilled in 1974. It operated continuously, as permitted, from June 1974 until it 

was plugged and abandoned in May 1994. The Texas UIC agency amended the permit 

in August 1985, and re-permitted it in August 1990. In December 1993, a staff 

member of the Texas Natural Resource Conservation Commission (TNRCC, the UIC 

primacy agency since September 1993), determined that the Woodbine injection zone 

(as originally permitted and constructed, from -2790 to -2960 feet) was actually a 

USDW, and contained water of about 5,000 mg/I TDS. Since 1974, WDW-117 was 

permitted to inject 150 gpm at 750 psig and up to 79 million gallons per year of 

hazardous and (after 1992) non-hazardous waste. In adjacent counties, the Woodbine 

injection zone serves as a drinking water source. After determining that the WDW-117 

injection zone was a USDW and notifying the permittee, TNRCC allowed Jetco to 

continue injecting for four months while Jetco developed surface treatment options. 

5.0 Comparison with 1988-1993 data 

The Class I well inventory has remained stable since the previous study (428 wells in 

1992 versus 432 in 1 998), although the number and percentage of Hazardous to Nonhazardous waste wells has decreased (240/188 or 56 percent in 1992 versus 60/264 

or 23 percent). 

5.1 All states except Texas 

The incidence and severity of internal MI failures in these Class I wells was found to 

decrease by half, compared to the previous 5-year study period (the ratio of well 

failures to active wells was 18 percent between 1993-1998 versus 33 percent 

between 1 988-1 993). Class I Non-hazardous waste wells in these states were found 

to fail at one-third the rate of Hazardous waste wells (13 percent for NHW wells 

versus 40 percent for HW wells), similar to the values observed during 1988-1993 (15 

percent NHW versus 64 percent HW). Twenty percent of MI failures between 1993­

1998 involved casing, versus 19 percent from 1988-1993 (Table 3). 
Class T MT Failure Analysis U993-1998) 15 

Table 3 


Comparison of 1993-1988 Data With 1988-1993 Data 


All States (except Texas) 

1993-1998 1988-1993 

Number of Wells 


Hazardous 60 wells 96 wells 


Non-hazardous 264 wells 188 wells 


MI Failures 

Hazardous (%) 24 failures (40%) 62 failures (64%) 

Non-hazardous (%) 34 failures (13%) 28 failures (15%) 

Total (%) 58 failures (18%) 90 failures (33%) 

Casing MI failures (%)' 11 esg fails (20%) 15 esg fails (19%) 

Texas 

Number of Wells 


Hazardous 70 wells 144 wells 


Non-hazardous 38 wells 2 


MI Failu.res3 

Hazardous (%) 63 failures (90%) 2 

Non-hazardous (%) 33 failures (87%) 2 

Total (%) 96 failures (89%) 45 failures (31 %) 

Casing MI failures (%)' 38 esg fails (66%) 8 esg fails (18%) 

Percent of certain MI failures with known reasons 


Although wells in Texas injected both HW and NHW waste streams, Texas did not 


distinguish between HW and NHW during the 1988-1993 timeframe. 


Includes 19 probable MI failures (15 H/4 N) and 6 external MI failures (4 H/2 N). 


NQ1e.: All % values refer to the ratio of well failures to active wells, not to the 

fraction of wells that failed (many wells failed several times as noted in 

footnote 9 on p. 9). 

3 
Class I MI Failure Analysis U993-19981 16 

5.2 Texas 

In Texas, internal MI failures from 1993-1998 were found to almost triple compared 

to the previous study (90 internal MI failures/well failure to active well ratio of 83 

percent, versus 45 failures/well failure to active well ratio of 31 percent from 1988­

1993).19 Furthermore, the severity of MI failures in Texas (as denoted by incidence 

of long-string casing failure) also was found to almost quadruple (38 cases/66 percent 

of certain MI failures with known reasons, versus 8 cases/18 percent for the previous 

study). In Texas, Hazardous and Non-hazardous Class I wells experienced MI failures 

at a similar rate (84 percent HW versus 82 percent).19 For the 1993 study, however, 

Texas made no distinction between Hazardous and Non-hazardous waste wells, and 

no HW /NHW comparison is possible. 

We were concerned that the increase in Texas MI failures was due to undercounting 

failures for the 1993 study. We performed similar screening of the Texas Class I files 

in both 1993 and 1998. The 1993 screening was performed with microfiche, 

whereas the 1998 screening was done with unsorted paper files. It may have been 

easier to locate references to MI failures in the paper files of 1998, compared to the 

microfiche files of 1993. 

On the other hand, we found in the 1993 study that the incidence and severity of 

Texas MI failures were almost identical to those of all other states: 31.7 percent for 

Class I wells in 14 other states versus Texas at 31.2 percent, and 19 percent casing 

failures versus 18 percent for Texas. Based on these data, we do not believe that MI 

failures were undercounted for the 1993 study, but that MI failures have increased 

since then. There is no lessening of the effect in either case, however, because: 

• 	 if we undercounted in 1993, Texas MI failures have occurred much more frequently 

than the national average since 1988; or 

• 	 if we did not undercount, Texas MI failures have occurred much more frequently 

than the national average only since 1993. 

19Includes probable MI failures for both 1993-1998 and 1988-1993. 
Class T MI Failure Analysis U993-J998) 	 17 

5.3 	External MI and Migration 

For the 1993 study, we reported only 5 cases of waste migration (3 Florida, 1 

Michigan, 1 Ohio), all involving Non-hazardous waste. We reported only one case of 

actual external MI failure. 

For the current study (1993-1998), we reported 11 cases of external MI loss, and 27 

cases of waste migration from the injection zone. We are unsure if incidents of 

external MI failure and migration have actually increased since 1993. Two factors may 

help to explain the perceived increase: 

1. 	 Migration of groundwater is relatively slow, and migration may have been 

occurring for some time before being discovered only recently. 

2. 	 Improvements in MIT detection technology and standardization of MIT methods 

may be partly responsible for the perceived increase during the 1993-1998 

timeframe. It may be that more incidents are being detected, rather than more 

occurring. 

APPENDIX A 

Class I MI Failure Analysis (1993-1998) 

September 30, 1998 

Contract No. 68-C6-0029 

Work Assignment No. 11 

Key to Abbreviations 

tbg = tubing 

pkr = packer 

csg = casing 

migr = migration 

unsp = non-specific annulus leak 

extMI = external Mechanical Integrity 

monit. = monitoring 

P & A = plug and abandon 

RAT = radioactive tracer test 

FLORIDA 


The Class I primacy program is administered by the Florida Department of Environmental 

Regulation. In FY 1997, EPA reports that 130 Class I wells were active, one injecting 

Hazardous and 129 Non-hazardous wastes (1993: 1 H, 123 NH).· The FL DER cited three 

internal MI failures and 17 external MI failures of Class I Non-hazardous wells. The dates 

shown for some external MI failures represent the earliest date migration was suspected, 

although subsequent testing since 1992 has served to confirm the extent and amount. Those 

incidents with dates preceding February 1992 were not included in the previous report because 

migration had not been confirmed at that time. 

All of these cases of external MI failure involved Class I Non-hazardous wells injecting 

secondary-treated municipal sewage (listed as "Muni" in attached summary). Upward 

migration took place into unpermitted zones above the injection zone. However, with the 

exception of three facilities, this fluid movement has not involved a USDW. Where fluid 

movement into a USDW has occurred, the quality of the USDW has been gene'rally poor (TDS 

greater than 3,000 - 7,000 mg/l). All occurrences of fluid movement into unpermitted zones 

were detected by State-mandated monitoring well programs, required as preventive measures 

in excess of the Federal minimum standards. These monitoring wells were located in each 

case within 150 feet of the injection well, completed in a zone between the top of the injection 

zone and the base of the lowermost USDW. Fluid migration is suspected to occur due to 

small-scale natural fracturing in limestone/dolomite confining zones, although in 3 of 17 cases 

migration occurred due to deficiencies in the construction of the monitoring wells. 

Source of data: Florida Department of Environmental Regulation (R. Deuerling) 

Type of MI failure 1993-1998 	 1988-1993 

Tubing failure 	 1 

Packer failure 2 	 (casing) 

Waste migration 	 17 * ~(none USDW) 

20 (none haz) 5 (none haz) 

Note: * Three cases feature proven migration into USDWs, 8 cases feature suspected migration into USDWs, and 6 

cases feature proven migration into unpermitted saline zones. 

"well inventory totals are for"Active" wells, either specified by State programs or taken from Injection Well Inventory, 

FY 1997 and 1992, U.S. EPA UIe Program, Office of Ground Water and Drinking Water. 
Summary of Class I MI failures in Florida (2/93 - 7/98' 

Source: Florida Dept. of Environmental Regulation 

Waste Outside 

Operator Well No. Haz? Date Type of Failure Response Weliborellnj.Zone? 

Martin County Utilities 

North facility Plant IW1 N Aug 96 Packer failure Downgraded' No 

Jensen Beach 

Charlotte County Utilities 

Zemel Rd. Landfill Plant IW1 N Jun 97 Packer failure Replace packer No 

Punta Gorda 

City of Plantation Utilities 

Central RO plant Plant IW1 N Jan 95 Tubing failure Replace tubing Yes, to unpermitted 

saline zone 

Regional WWTP 2 wells N (muni) Jan 97 	 Waste migration due Re-permit injection Yes, to unpermitted 

to poor confinement zone to include saline zone 

Miami-Dade Water & Sewer 

S. District 17 wells N (muni) Jul 94 	 Waste migration Orders on Consenf Yes, to unused USOW 

Regional 	 WWTP due to monitor well (> 7,000 mg/l TDS) 

internal MI failure 

Seacoast Utilities Plant IW1 N (muni) Aug 93 Waste migration due USDW exemption Yes, to USDW 

Palm Beach Gardens to poor confinement requested 

Broward County 4 wells N (muni) Dec 91 Waste migration due re-permit injection Yes, to unpermitted 

North Regional WWTP to poor confinement zone to include saline zone 

City of Ft Lauderdale 

G.T. Lohmeyer 5 wells N (muni) Feb 91 	 Waste migration repair monit. well Yes, to unpermitted 

WWTP 	 due to monitor well saline zone 

external MI failure 

'Downgraded by Director from Industrial Waste category to Municipal treated waste injection only; municipal 

waste wells do not require tubing and packer. 

2Plugged back injection-zone monitoring well; also conducting studies concerning geologic confinement as 

contributing to migration. Migration discovered by State-ordered monitoring network, more stringent 40 CFR 146 

UIC regs. Continuing operation at present under Corrective action order. 

2 
Summary of Class I MI failures in Florida (2/93 - 7198) (cont'd) 

Source: Florida Dept. of Environmental Regulation 

Waste Outside 

Operator Well No. Type of Failure Response Welibore/lnj.Zone? 

Palm Beach County Utilities 

South Regional 2 wells N (muni) Jul 94 Waste migration due in progress3 Yes, into USDW? 

WWTP to poor confinement 

City of St. Petersburg Utilities 

Whitted WWTP 2 wells N (muni) Mar 91 Waste migration due none reported Yes, to USDW 

to poor confinement 

Northeast WWTP 4 3 wells N (muni) Mar 91 	 Waste migration due in progress Yes, into USDW? 


to poor confinement 


Northwest WWTP 2 wells N (muni) Mar 91 	 Waste migration due in progress Yes, into USDW? 


to poor confinement 


Southwest WWTP 3 wells N (muni) Mar 91 	 Waste migration due in progress Yes, into USDW? 


to poor confinement 


Pinellas County Utilities 

South Cross Bayou 3 wells N (muni) Mar 91 Waste migration due in progress Yes, into USDW? 

WWTP to poor confinement 

St. Petersburg 

McKay Creek WW 2 wells N (muni) Mar 91 Waste migration due in progress Yes, into USDW? 


Largo to poor confinement 


Brevard County Utilities 

Sykes Creek WTP 2 wells N (muni) Dec 86 Waste migration due in progress Yes, into USDW? 

Merrit Island to poor confinement? 

S. Beaches 	 WWTP 1 well N (muni) Dec 86 Waste migration due Re-permit inj. Yes, to unpermitted 

Melbourne to poor confinement zone to include saline zone 

~ity of Melbourne Utilities 

D.B. 	 Lee WWTP 1 well N (muni) Mar 89 Waste migration due P & A Yes, to unpermitted 

to poor confinement saline zone 

(and external MI?) 

3Drilling additional monitoring wells to determine if fluid has moved into base of lowest USDW; if so, will 

petition for aquifer exemption. 

41nvestigation in progress to determine if waste entered base of lowermost USDW. 

3 
Summary of Class I MI failures in Florida (2/93 - 7/98) (cont'd) 


Source: Aorida Dept. of Environmental Regulation 


Waste Outside 

Operator Well No. Tvpe of Failure Response Weliborellnj.Zone? 

City of Melbourne Utilities (cont'd) 

Grant St. WWTP 1 well N (muni) Sep 89 	 Waste migration due Consent Order Yes, to unpermitted 

to poor confinement saline zone 

(and external MI of 

monitoring well?) 

City of Sunrise 3 wells N (muni) Nov 91 Waste migration due re-permit inj. Yes. into unpermitted 

to poor confinement zone to include saline zone 

4 

KENTUCKY and TENNESSEE 


The Class I program in these States is directly administered by EPA Region IV. Although 16 

wells were active in for the 1993 study in Kentucky and Tennessee, these wells have been 

plugged by 1998. Region IV reports no MI failures of Class I wells from 1993 to 1998. 

(1988-1993 data: no MI failures) 

Source of data: EPA Region IV (N. Marsh, Class I coordinator) 

MISSISSIPPI 

The Class I primacy program is administered by the Mississippi Department of Environmental 

Ouality. EPA reports that seven Class I wells were active in FY 1997, two Hazardous and five 

Non-hazardous (1992: 5H and 1 NH). The Mississippi DEO (J. Crawford) reports that between 

2/93 and 8/98, three Class I hazardous wells experienced MI failures (1988-1993: six). 

Type of MI failure 1993-1998 1988-1993 

Hazardous well 3 (2 tubing, 1 casing) 5 (5 tubing) 

Non-Hazardous well --.0.... ...J...( 1 packer) 

3 6 

5 

·Summary of Class I MI failures in Mississippi (2/93 - 7198) 

Source: Mississippi Department of Environmental Quality (J. Crawford) 

Operator Well No. Type of Failure Response 

Waste Outside 

WellborellnLZone? 

E.I Dupont 

De Lisle Plant #1 y Feb 94 Tubing failure Replace tubing No 

Plant #2 y Sep 95 Casing leak Sidetrack No 

Plant #3 y Dec 95 Tubing failure Squeeze and 

sidetrack 

No 

6 

INDIANA 


The Class I program is administered by EPA Region 5. In 1998, Region 5 reports that eleven 

wells were active, four injecting Hazardous and seven Non-hazardous wastes (1993: 13 wells, 

7H and 6 NH). Three MI failures were observed (two in Hazardous wells), versus four between 

1988-1993. 

Source of Data: EPA Region 5 (N. Wiser) 

Type of MI failure 1993-1998 1988-1993 

Hazardous well 2 (1 tubing, 1 casing) 4 (1 tubing, 3 casing) 

Non-Hazardous well _1(1 casing) ....Q.. 

3 4 

7 

Summary of Class I MI failures in Indiana (2/93 ­ 7198) 

Source: EPA Region 5 

Operator Well No. Haz? Date Type of Failure Response 

Waste Outside 

WellborellnLZone? 

Bethlehem Steel 

Chesterton 

127·1·1 Y Nov 93 

Apr 98 

Casing Leak 

Tubing leak 

Install liner 

Replace tubing 

No 

No 

Hoskins Mfg. 

New Paris 

39-11-1 N Jul 96 Casing leak Squeeze-cement No 

8 

ILLINOIS 


The Class I primacy program is administered by the Illinois Environmental Protection Agency. 

Region 5 reports that in 1998, six wells were active, all Hazardous (1993: 5H and 3 NH). One 

MI failure was recorded (Haz well), versus four between 1988-1993. 

Source of Data: EPA Region 5 (N. Wiser) 

Type of MI failure 1993-1998 1988-1993 


Hazardous well 1 (1 tubing) 4 (1 tubing, 3 packer) 


Non-Hazardous well -..0... 


4 


9 

Summary of Class I MI failures in Illinois (2/93 - 7198) 

Source: EPA Region 5 

Waste Outside 

Operator Well No. Type of Failure Response Weliborellnj.Zone? 

LTV Steel 4-Wl-JL y Mar 94 Tubing leak Replace tubing No 

Hennepin 

10 

MICHIGAN 


The Class I UIC program in Michigan is administered by EPA Region V. In 1998, Region 5 

reports that 22 wells were active, 9 Hazardous and 13 Non-hazardous (1993: 25, 13 Hand 

12 NH). Eleven Class I MI failures were observed from February 1993 to July 1998 (2 

injecting Hazardous waste versus 9 Non-hazardous), compared to 18 failures observed 

between 1988-1993. 

Source of Data: EPA Region V (N. Wiser) 

Type of MI failure 1993-1998 1988-1993 

Hazardous well 2 (2 tubing) 10 (1 tbg, 6 pkr, 1 unsp, 1 whd, 1 csg) 

Non-Hazardous ...9. (3 tbg, 3 pkr, 1 whd, 1 unsp, 1 csg) --.8...(4 tbg, 1 whd, 2 csg, 1 migr) 

11 18 

11 

Operator 

Heinz USA 

Holland 

Hoskins Mfg. 

Milo 

Kalium Chemicals 

Hersey 

Upjohn 

Kalamazoo 

Well No. 

139-11-1 

139-11-2 

139-11-3 

135-11-1 

133-11-1 

133-11-2 

77-1W-1 

Summary of Class I MI failures in Michigan (2/93 - 7198) 

Source: EPA Region 5 

Haz? Date Type of Failure Response 


N Nov 95 Packer leak Reset packer 


Oct 97 Tubing leak Replace tubing 

N Mar 97 Tubing leak Replace tubing 

N Feb 94 Casing leak Install liner 

Sep 94 Wellhead leak Repair wellhead 

N 	 Mar 97 Annulus leak Unknown 

Jun 97 Tubing leak Replace tubing 

N Feb 96 Packer leak Reset packer 

N Sep 96 Packer leak Reset packer 

y 	 Jun 95 Tubing leak Replace joints 

Apr 96 Tubing leak Replace tubing 

Waste Outside 

Wellbore/lnLZone? 

No 

No 

No 

No 

No 

No 


No 


No 


No 


No 


No 


12 

OHIO 


The Class I primacy program is administered by the Ohio Environmental Protection Agency. 

Region 5 reports thirteen wells active in 1998, ten injecting Hazardous waste and three Nonhazardous (1993: 16, 9 Hand 7 NH). Three Class 1 MI failures were observed between 

February 1993 and July 1998 (2 injecting Hazardous waste), compared to 13 from 1988­

1993. 

One current incident is an external MI failure, in which data from well tests and samples from 

a deep monitoring well indicated that waste has migrated from the injection zone into the 

permitted saline "Containment Interval" underlying the Confining zone. 

Source of Data: Ohio E.P.A. (Amy Klei) 

Type of MI failure 1993-1998 1988-1993 

Hazardous well 2 (1 casing, 1 migration) 11 (6 tbg, 2 pkr, 3 unsp) 

Non-Hazardous well .J. (1 casing) .2.,.(1 pkr, 1 migration) 

3 13 

13 

Summary 	of Class I MI failures in Ohio (2/93 - 7198) 

Source: Ohio Envr. Prot. Agency 

Waste Outside 

Operator Well No. Haz? Type of Failure Response Weliborellnj.Zone? 

BP Chemicals 

Lima 

03-02-003 Y Nov 93 Casing leak Replace joints 

Tomen 

Perry 

Agro 02-43-006 N Apr 91 Casing leak Install liner No 

Waste Mgmt 

Vickery 

of OH 4 wells Y Unknown Waste migration due 

to poor confinement 

Increase monitoring Yes6 

BAn improper wellhead connection caused fresh water to corrode the uppermost casing, from the outside-in. 

Approximately 25 gallons of annulus-protection fluid (propylene glycol) was spilled onto the concrete wellhead pad, 

but was recovered before contact with the soil. Release of waste was not involved. 

8Mechanical Integrity tests and data from a deep monitoring well indicate that waste has moved from the 

Injection Interval (top @ -2800 feet) into the Containment Interval (@ -2500 feet). contrary to predictions made 

for the HSWA Exemption Petition. Note that the Containment Interval underlies the Confining Zone, into which 

waste is prohibited from entry. No waste migration into or degradation of the lowermost USDW (@ -500 feet) 

has been observed in a dedicated USDW monitoring well. The well is continuing operation under increased 

monitoring. 

14 
ARKANSAS 


The Class I primacy program is administered by the Department of Pollution Control and 

Ecology. EPA reports that 16 wells were active in FY 1997, six Hazardous and ten Nonhazardous (1993: 12 wells, 5 Hand 7 NH). Six MI failures have been observed since 1993, 

one of which involved hazardous waste. 

Source of data: AR Dept. of Pollution Control and Ecology (G. Delavan, UIC Coordinator). 

Type of MI failure 1993-1998 1988-1993 

Hazardous well . 1 (1 packer) 4 (1 tubing, 3 packer) 

Non-Hazardous well -.li (1 tubing, 3 packer, 1 whd) 2.,(1 tubing, 1 packer) 

6 6 

15 

Summary of Class I MI failures in Arkansas (1194· - 7/98' 

Source: Arkansas Department of Pollution Control and Ecology 

*Note: AR DOPC&E was unable to access MI records for year 1993. 

Operator Well No. Haz? Date Type of Failure Response 

Albermarle Corp. WDW 1 Y Apr 95 Packer leak Reset packer 

Magnolia 

Great Lakes Chemical Corp. 

Marysville WDW 14M N Jun 94 Packer leak Replace packer 

EI Dorado WDW 7 N May 94 Tubing leak Replace joints 

WDW 3x N May 94 Packer leak Reset packer 

Feb 95 Wellhead leak Adjust fitting 

Newell WDW 7N N Oct 97 Packer leak Replace packer 

Waste Outside 


Weliborellnj.Zone? 


No 

No 

No 

No 

No 

No 

a 

16 
LOUISIANA 


The Class I primacy program is administered by the Louisiana Department of Natural 

Resources. In FY 1997, EPA reports that 42 wells were active, 17 Hazardous and 25 Nonhazardous (1993: 53 wells, 39 Hand 14 NH). Twenty two MI failures were observed from 

February 1993 to July 1998, versus 32 failures between 1988-1993. 

Source of data: 	 ICF analysis of Louisiana DNR well workover files (and other information 

furnished by Joe Ball) 

Type of MI failure 	 1993-1998 1988-1993 

Hazardous well 	 12 (8 tbg, 2 pkr, 2 csg) 23 (6 tbg, 6 pkr, 1 unsp, 3 whd, 7 csg) 

Non-Hazardous well 	 1.Q (6 tbg, 2 pkr, 2 csg) ~(7 tbg, 1 pkr, 1 csg) 


22 32 


17 

Summary of Class I MI failures in Louisiana (2/93 - 7198) 

Source: ICF analysis of Louisiana DNR records 

Operator Well No. Type of Failure Response 

Waste Outside 

WellborellnLZone? 

Borden Chemical 

Geismar 

#3 N May 98 Packer leak Replace packer No 

Calumet Lubricants 

Princeton 

#2 N Jan 94 Packer leak Replace pkr No 

Chevron Chemical 

Belle Chasse 

#2 N Aug 93 

Mar 94 

Tubing 

Tubing 

leak 

leak 

Replace 

Replace 

tubing 

tubing 

No 

No 

#3 N Aug 93 Tubing leak Replace tubing No 

Mar 94 Tubing leak Replace tubing No 

CYTEC Industries 

Westwego7 

#1 Y Jan 93 

Dec 95 

Tubing 

Tubing 

failure 

failure 

Replace 

Replace 

tubing 

tubing 

No 

No 

Dec 96 Tubing failure Replace tubing No 

#2 y Nov 95 Tubing failure Replace tubing No 

E.I. DuPont 

LaPlace 

#7 Y Jan 94 

May 94 

Tubing 

Tubing 

leak 

leak 

Replace joint 

Re-torque joint 

No 

No 

Laidlaw Environmental 

Bayou Sorrels 

#1 Y (C) Apr 98 Casing leak Squeeze and patch No 

Monsanto 

Luling 

Ag Products #2 

#4 

N 

N 

Aug 95 

Jan 98 

Casing 

Casing 

leak 

leak 

Install liner (500') 

Squeeze 

No 

No 

Rubicon Chemical 

Geismar 

#1 Y Jun 93 

Apr 95 

Packer 

Casing 

leak 

split 

Replace packer 

Sidetrack 

No 

No 

#2 y Jun 95 Packer leak Reset packer No 

7formerly American- Cyanamid, Inc. 

Sformerly Rollins Environmental Services 18 
Summary of Class I MI failures in Louisiana (2/93 - 7198) (cont'd) 

Source: ICF analysis of Louisiana DNR records 

Waste Outside 

Operator Well No. Type of Failure Response Weliborellni.Zone? 

Rubicon (cont'd) #4 y Dec 94 Tubing leak Replace tubing No 

Geismar 

Aug 96 Tubing leak Replace tubing No 

Witco Chemical #3 N Mar 95 Tubing failure Replace tubing No 

Taft 

#4 N Aug 95 Tubing leak Replace tubing No 

19 

OKLAHOMA 


The Class I primacy program is administered by the Oklahoma State Department of Health. 

EPA reports that 11 Class I wells were active in FY 1997, all Non-hazardous (1993: 12 wells, 

5H and 7 NH). 

The Oklahoma State Department of Health observed no MI failures in Class I wells between 

1988 and 1993. In fact, they have reported only two minor MI losses for all Class I wells 

since 1988. 

Source of Data: OK State Dept. of Health (D. Barrett, Chief Environmental Engineer) 

Type of MI failure 1993-1998 1988-1993 

Hazardous well o 1 (1 tubing) 

Non-Hazardous well ...Q _1_(1 packer) 

o 2 

20 

TEXAS 


The Class I program in Texas is administered by the Texas Natural Resource Conservation 

Commission. TNRCC reports that in 1998, 108 Class I wells were active (70 injecting 

Hazardous waste and 38 Non-hazardous). Ninety-six MI failures were observed from February 

1993 to July 1998, 77 definite and 19 probable" (based on incomplete records). For the 

previous study, Texas was found to have 144 Class I wells, 73 Hand 71 NH, and experienced 

45 MI failures between 1988 and 1993. 

Class I wells in Texas experienced a higher percentage of MI failures from 1993-1998 than 

was observed in the previous study (89 percent versus 31 percent over 5 years), and the MI 

failures incorporated a much larger proportion of casing failures, a more serious type of MI 

failure (38 cases and 66 percent of all definite failures, versus 8 cases and 18 percent). In 

addition, from 1993-1998 Class I wells in Texas experienced eight cases of waste migration 

(six cases into unpermitted zones), and a well injecting since 1974 was found to be permitted 

to inject directly into a USDW (Jetco Chemicals, WDW-117). 

Source of data: ICF analysis of TNRCC files, and other data supplied by TNRCC (courtesy 

B. Knape, C. Green, and K. Cronan). 

Type of MI failure 1993-1998 1988-1993 

Hazardous well 50 (9 tbg, 4 pkr, 11 unsp, 45 (22 tbg, 4 pkr, 11 unsp, 8 csg) 


20 csg, 6 extMI) 


Non-Hazardous n (5 tbg, 2 pkr, 2 unsp, 18 csg) --.U..(no haz/non-haz distinction until 1993) 

77 (not including 19 probable) 45 

"These probable cases involved references in correspondence to MI-type workover operations (e.g., squeezecementing or replacing a tubing string), but no specific references to loss of Mechanical Integrity and/or details of the 

procedure. Some references were fairly definite but not positive (e.g., Casing leak?), others strongly suggested MIrelated activities (reported as Lost MI?), whereas the majority of references to probable cases indicated only that a 

major workover of MI-type components took place (e.g., Major workover). 

21 
Summary of Class I MI failures in Texas (2/93 - 7198) 

Source: ICF analysis of Texas files and other 

data supplied by TNRCC 

Operator Well No. Haz? Date Type of Failure Response 

Waste Outside 

Weliborellnj.Zone7 

American 

Winona9 

Ecology WOW·186 Y Oct 92 

Dec 92 

Casing leak 

Failed MIT 

? No 

WOW-229 Y Feb 93 

May 93 

Nov 94 

Failed MIT 

Failed MIT 

Casing leak 

? 

? 

Straddle-packers 

? 

? 

ARCO 

Channelview 

WOW-148 y Oct 96 Casing leak Sidetrack Yes, to permitted 

saline zone 

ASARCO 

Amarillo 

WOW-129 

WOW-324 

y 

N 

Sep 93 

Aug 97 

Major workover 

Casing leak 

? 

Squeeze-cement 

? 

BASF 

Freeport 

WOW-51 

WOW-99 

y 

y 

Jan 

Feb 

95 

93 

Casing leak? 

Failed MIT 

Sidetrack 

? 

? 

BP Chemicals 

Port Lavaca 

WOW-165 y Mar 95 Major workover ? ? 

Cogema 

Bruni 

Mining 

WOW-150 N Feb 96 Casing leak and 

poor ext. MI 

Squeeze-cement ? 

WOW-1S1 N Mar 96 Annulus leak Replace tbg & pkr No 

WOW-19S N Jul 94 Casing plus 

annulus leak 

Squeeze plus 

replace tbg & pkr 

? 

Holiday-Mesquite WOW-197 N May 93 Major workover ? ? 

9formerly Gibraltar Wastewater, Inc. 22 
Summary of Class I MI Failures in Texas (cont'd) 

Operator Well No. Type of Failure Response 

Waste Outside 

Wellbore/lni-Zone? 

Chern Waste 

Port Arthur 

Management 

WOW-160 V Jun 94 

Jan 95 

May 95 

Jun 95 

Aug 97 

Feb 98 

Casing leak 

Casing leak 

Tubing leak 

Annulus leak 

Packer leak 

Casing leak 

(new) 

Squeeze and 

install liner 

Straddle packer 

Replace joint(s) 

Reset packer 

Squeeze and 

sidetrack 

? 

No 

? 

No 

Corpus Christi'O WDW-70 Y May 93 Packer leak Reset packer No 

Diamond 

McKee 

Shamrock WOW-192 V Jul 97 Casing leak Reset packer 

higher 

No 

E.!. DuPont de Nemours 

Beaumont WOW-100 V Jun 

Mar 

94 

97 

Lost 

Lost 

MI? 

MI? 

Replace 

Replace 

tbg & pkr 

packer 

No 

No 

WDW-101 V Feb 93 Lost MI? Squeeze and 

sidetrack 

No 

Ingleside WDW-109 N Sep 93 Casing leak. 

no ext. MI 

P&A Yes, to unpermitted 

saline zone 

WDW-121 N Mar 94 Casing leak 

no ext. MI 

P & A Yes, to unpermitted 

saline zone 

LaPorte WDW-82 N Jan 95 Casing leak Straddle-packers 

Sabine Works WOW-57 Y Mar 97 Ext. MI loss Squeeze 

P & A 

and Yes, to permitted 

saline zone 

WDW-191 y Dec 95 

Aug 96 

Nov 97 

Apr 98 

Casing/tbg failure 

Major workover 

Casing leak 

Casing leak (same?) 

Sidetrack 

? 

Squeeze 

No 

? 

WDW-207 Y Aug 95 Major workover 

'o,-he Corpus Christi site is now owned and operated by the GNI Group as Disposal Systems Inc., Corpus 

Christi. 

23 
Summary of Class I MI Failures in Texas (cont'd) 

Waste Outside 

Operator Well No_ Type of Failure Response Wellborellni-Zone? 

E.!. Dupont (cont'd) 

Victoria WDW-30 Y Mar 96 Tubing leak Re-thread No 

WDW-142 Y Jan 93 Casing leak Squeeze-cement 

WDW-144 Y Jul 98 Casing leak Squeeze-cement 

WDW-145 Y Jul 94 Failed MIT 

Jan 96 Packer leak Replace packer No 

Elf Atochem WDW-122 N Jul 95 Packer leak Repair packer No 

Crosby 

Empak, Inc. WDW-157 Y Mar 94 Major workover 

Deer Park 

GNI" WDW-169 Y Jul 93 Tubing failure Replace tbg & pkr No 

Deer Park Sep 93 Tubing failure (new) Replace tubing No 

Jun 96 Tubing leak Replace tubing No 

Jan 98 Lost MI? Recomplete higher 

Hampshire WDW-222 N Mar 95 Tubing leak Replace tubing No 

Deer Park 

Hoecst-Celanese 

Bay City WDW-14 Y Feb 94 Casing leak P & A Yes, to unpermitted 

saline zone 

WDW-32 Y Jun 96 Annulus leak P & A 

WDW-49 Y Oct 93 Tubing leak Replace tbg & pkr No 

Mar 94 Casing leak ? 

WDW-ll0 Y Jan 95 Major workover 

Bishop WDW-212 Y May 93 No ext. MI Squeeze-cement Yes, to unpermitted 

saline zone 

Clear Lake WDW-45 Y Jun 98 Annulus leak 

"formerly Disposal Systems Inc. 

24 
Summary of Class I MI Failures in Texas (cont'd) 

Operator 

ISP Technologies 

Texas City 

Jetco Chemicals 

Corsicana 

Malone Services 

Texas City 

Monsanto 

Chocolate Bayou 

Oxy Petrochemicals 

Corpus Christi 

ilexene 

Odessa 

Well No. 

WOW-34 Y 

WOW·114 Y 

WOW-299 Y 

WOW-117 N 

WDW-73 Y 

WOW-2 Y 

WDW-224 Y 

WDW-152 Y 

WOWs 16, Y 

88, 126, 154 

Date 

Dec 94 

Jan 96 

Jan 97 

Feb 93 

Feb 93? 

Oct 93 

Dec 93 

Jul 95 

Feb 93 

Apr 93 

Nov 96 

Apr 97 

May 93 

Type of Failure 

Tubing leak 

Tubing leak 

Casing leak 

No ext. MI 

No ext. MI 

Casing leak 


Injection to USOW 


Annulus leak 


lost MI? 


Casing leak? 


Failed MIT 


Major workover (same) 


No ext. MI due 


to fractures 


Waste Outside 

Response Wellborellnj.Zone? 

Replace tbg & pkr 

Replace tubing 

Straddle-packers 

Temp. abandoned 

Temp. abandoned 

No 

No 

? 

Install liner 

P & A (5/94) 

? 

Yes, to USOW 12 

Replace tubing 

Squeeze-cement 

and sidetrack 

No 

? 

shut-in 

Replace tbg & pkr 

No 

No 

Quarterly RAT, 

Corrective Action13 

12This well was permitted by TNRCC in 1973 and drilled in 1974. It operated continuously, as permitted, from 

June 1974 until it was plugged and abandoned in May 1994 by order of the TNRCC. TNRCC amended the permit 

in August 1985, and re-permitted WOW-117 in August 1990. In December 1993, a TNRCC UIC staffer 

determined that the Woodbine injection zone (as originally permitted and constructed, from 2790-2960) was 

actually a USOW, containing water of about 5,000 mgll TOS. Since 1974, WOW-117 injected 150 gpm (max) 

at 750 psig WHIP (max), up to 79 million gallons per year of hazardous and non-hazardous (after 1992) waste. 

Up-dip from the Jetco facility, the Woodbine serves as a drinking water source. After determining that the WOW117 injection zone was a USOW, TNRCC allowed the operator to continue injecting for four months while Jetco 

developed surface treatment options. (Source: TNRCC WOW-117 file) 

131njection testing in May 1993 created fractures in the injection zone. Since 1997, the operator is required 

to operate at restricted injection rates, perform quarterly radioactive EMIT, and perform Corrective Action (such 

as plugging offset wells) in the Area of Review. Migration of waste from the injection zone is unknown. 

25 
Summary of Class I MI Failures in Texas (cont'd) 

Waste Outside 

Operator Well No. Date Type of Failure Response Weilbore/lnLZone? 

Sandoz'4 WDW-125 N Nov 93 Tubing leak Re-torque, reset No 

Beaumont Nov 97 Casing leak Squeeze-cement ? 

Mar 98 Major workover ? 

WDW-155 Y Apr 97 Packer leak Replace packer No 

WDW-301 N Oct 94 Casing leak ? No 

Mar 95 Casing failure (new) Install liner 

Aug 95 Major workover (new) ? ? 

Sterling Chemical WDW-196 Y May 96 Tubing failure, Replace tbg & pkr, ? 

Texas City casing leak reset higher 

WDW-314 Y Aug 97 Lost MI? Recomplete higher ? 

Mar 98 Casing failure Install liner and 

then sidetrack 

Thomas Disposal WDW-311 N Sept 93 Casing leak Squeeze-cement 

Perryton Mar 95 Major workover ? ? 

Feb 96 Casing leak Squeeze-cement ? 

USX Uranium WDW-123 N Mar 95 Casing leak Install liner, 

George West tubing, and packer 

WOW-140 N Aug 94 Packer leak and straddle packers 

casing leak 

May 96 Casing failure Uner, then ? 

sidetrack 

WDW-141 N Jan 95 Tubing leak Replace joints No 

Mar 95 Tubing leak Replace tubing No 

WDW-174 N Feb 93 Casing leak Squeeze-cement 

Witco Chemical 

Houston WDW-111 N Sep 95 Failed MIT ? ? 

Apr 96 Casing failure Recomplete higher ? 

WOW-139 N Aug 96 Casing failure Recomplete higher 

Dec 96 Lost MI? Replace tbg & pkr No 

14formerly BASF Corporation 

26 
Summary of Class I MI Failures in Texas (cont'd) 

Operator WeI! No. Tvpe of Failure Response 

Waste Outside 

WellborellnLZone? 

Witco Chemical 

Marshall 

(cont'd) 

WDW-180 Y Ssp 93 

Oct 94 

Nov 95 

Packer and 

casing leak 

Major workover(same?) 

Casing leak and 

no ext. MI 

Squeeze and 

sidetrack 

WDW-243 Y Dec 

Nov 

93 

97 

No ext. MI 

Tubing leak Replace tubing 

Yes, to unpermitted 

saline zone?16 

No 

Uranium 

Rosita 

Resources WDW-250 N Aug 95 

Oct 95 

Tubing and 

packer leak 

Packer leak 

Re-torque tbg and 

reset packer 

Replace packer 

No 

No 

16RAT test in 1993 showed upward migration along casing for over 300 feet, and probably out of injection 

zone. Subsequent tests show similar movement, including December 1997 (latest) test. Files are unclear if any 

regulatory. attention or restrictions visited on operator. 

27 
KANSAS 


The Class I primacy program is administered by the Kansas Department of Health and 

Environment. EPA reports that 66 Class I wells were active in Kansas in FY 1997, five 

Hazardous and 61 Non-hazardous (1993: 5H and 41 NH). Seven MI failures were observed 

in Class I wells between 1/93 and 7/98, two of which involved hazardous waste wells. 

Source of data: Kansas Dept·. of Health and Envr. (M. Cochran, Chief Geology Unit). 

Type of MI failure 1993-1998 1988-1993 

Hazardous well 2 (2 unspecified) o 

Non-Hazardous well ..Q (3 tbg, 1 pkr, 1 csg) --.U..* 

7 o 

Note: * Kansas did not furnish data for Class I Non-Hazardous wells for the previous study. 

28 

Summary of Class I MI failures in Kansas (2/93 - 7/98) 

Source: Kansas Department of Health and Environment 

Waste Outside 

Operator Well No. Haz? ...QM!L Type of Failure Response WeliborellnLZone? 

KN Processing Plant #2 N NA Tubing failure Replace tubing No 

Bushton 

Plant #4 N NA Tubing leak Replace joints No 

Plant #5 N NA Tubing leak NA No 

.<och Storage Plant #2 N NA Packer leak Reset packer No 

Conway 

Morton Salt Plant #1 N NA Casing leak Install liner No 

Hutchinson 

lulcan Chemicals Plant #3 y Sep 94 Annulus leak Replace tbg & pkr No 

Wichita 

Plant #8 y Aug 97 Annulus leak Replace tbg & pkr No 

29