Appeal from the Circuit Court of Cook County. No. 01 CH 11229. Honorable William Maddux, Judge Presiding.
 The opinion of the court was delivered by: Justice Gordon
 This appeal arises from ongoing complex litigation pending in the circuit court of Cook County. In 1993, Emerson Electric Co. (Emerson) and 15 of its subsidiaries brought an action for declaratory judgment*fn1 against 57 separate insurance carriers. Plaintiffs sought a determination that the insurers owed them coverage under comprehensive general liability (CGL) insurance policies purchased by Emerson for liabilities incurred as a result of damage to the environment at 64 sites located in 26 different states. The numbers of parties and sites have since been reduced, primarily through settlements and dismissals.*fn2 Republic Insurance Company (Republic) is the only insurer party to this appeal.*fn3
 In January of 2001, we considered an earlier appeal brought by plaintiffs and found that Missouri law applies to the interpretation of the insurance policies at issue.*fn4 Our ruling, in relevant part, reversed an interlocutory order in favor of Republic concerning the site in Hatfield, Pennsylvania, reversed certain grants of summary judgment in favor of Republic concerning plaintiffs' claims for coverage with respect to sites in Maysville, Kentucky; Erie and York, Pennsylvania; and Dixiana, South Carolina, and remanded the matter for further proceedings.
 On remand, the trial court regranted summary judgments in favor of Republic with respect to plaintiffs' claims for coverage for polluted sites located in Erie and Hatfield, Pennsylvania, and Dixiana, South Carolina. The court also granted summary judgments in favor of Republic with respect to polluted sites not implicated in the prior appeal, which were located in Vernon, Alabama; Shreveport, Louisiana; Philadelphia, Mississippi; and Melville, New York. Plaintiff Emerson and its subsidiaries, Ridge Tool Company, Therm-O-Disc Inc., Wiegand Appliance, Poulan/Weed Eater, U.S. Electrical Motors, McPhilben Lighting Company and Brooks Instruments (hereinafter referred to collectively as plaintiffs), now appeal. For the reasons that follow, we affirm in part, and reverse and remand in part.
 The facts of this case were set out in detail in our opinion deciding the previous appeal in this matter in Emerson Electric Co. v. Aetna Casualty & Surety Co., 319 Ill. App. 3d 218, 743 N.E.2d 629 (2001) (hereinafter Emerson I). Therefore, we will only focus on the facts relevant to this appeal.
 There are two categories of polluted sites at issue on this appeal: (1) two third-party waste disposal sites (third-party sites or waste disposal sites), with respect to which plaintiffs are seeking insurance coverage for costs associated with investigation and remediation of the sites, and (2) five sites owned by plaintiffs (owned sites), with respect to which plaintiffs are seeking insurance coverage for pollution arising out of manufacturing activities.
 Republic had issued two excess CGL policies to Emerson in connection with those sites. Policy No. CDU15502 (the 1983-84 policy) was effective from November 1, 1983, to November 1, 1984, and Policy No. CDU16724 (the 1984-85 policy) was effective from November 1, 1984, to November 1, 1985. The 1983-84 policy contains the following relevant language:
 To indemnify the Insured for all sums which the Insured shall be obligated to pay by reason of the liability imposed upon him by law or liability assumed by him under contract or agreement for damages, and expenses, all as included in the definition of 'ultimate net loss,' because of:
 (b) [p]roperty damage *** as defined herein and caused by or arising out of an occurrence[.]
 The term 'occurrence' shall mean (a) an accident, or (b) an event, or continuous or repeated exposure to conditions, which results during the policy period, in personal injury, property damage, or advertising liability *** neither expected nor intended from the standpoint of the Insured.
 It is agreed that this policy does not apply to liability for personal injury or property damage arising out of the discharge, dispersal, release, escape or seepage of smoke, vapors, soot, fumes, acids, alkalis, toxic chemicals, liquids or gases, waste material, or other irritants, contaminants or pollutants into or upon land, the atmosphere or any watercourse or body of water, unless such discharge, dispersal, release or escape is accidental." (Emphasis added.)
 With respect to the foregoing pollution exclusion, Emerson had requested and paid consideration for deletion of the words "sudden and" from the standard-form "sudden and accidental" exception to that exclusion, resulting in the language stated above in italics, which only utilizes the term "accidental." The 1984-85 policy contains the same relevant language as the 1983-84 policy, with the only difference being that its exception to the pollution exclusion contains the standard-form language "sudden and accidental."
 In Emerson I, we held, in pertinent part, that: (1) Missouri law must be applied to determine defendants' coverage obligations regardless of the location of the site; (2) under Missouri law, the standard-form "sudden and accidental" language of the exception to the pollution exclusion means both abrupt and unexpected and precludes coverage for property damage caused by gradual, nonabrupt releases of pollutants; (3) under Missouri law, the amended "accidental" language of the exception to the pollution exclusion means unexpected and does not preclude coverage for property damage caused by gradual, nonabrupt releases of pollutants; (4) under Missouri law, in determining whether the pollution was accidental, the focus is on the resulting damage, as opposed to the initial discharge or shipment of pollutants, and whether the resulting damage was intentional; and (5) under Missouri law, plaintiffs' showing of an "exposure to conditions" resulting in continuing damage to property during the policy period satisfies the initial burden of proving an "occurrence,"*fn5 as defined in the policies at issue; plaintiffs need not identify a specific event or release which caused the exposure to conditions. Emerson I, 319 Ill. App. 3d at 241, 243, 244-46, 253-54, 743 N.E.2d at 646, 647, 648-50, 655. As noted, the matter was remanded for further proceedings.
 On remand, the trial court granted summary judgments in favor of Republic concerning the two third-party waste disposal sites based on the lack of "occurrence" as it is defined in the 1983-84 policy,*fn6 discussed more fully below. The court also granted summary judgments in favor of Republic concerning the owned sites based on the 1984-85 policy's standard-form "sudden and accidental" exception to the pollution exclusion and the 1983-84 policy's customized "accidental" exception to the pollution exclusion, as detailed, respectively, below. Notably, in granting summary judgments with respect to the owned sites, the trial court, in contrast to its focus in determining coverage as to the third-party sites, did not look to the definition of "occurrence" but, rather, looked to the language of the pollution exclusion as precluding coverage because it found the pollution at the owned sites not "accidental," irrespective of whether or not the discharges were "sudden."
 The Third-Party Sites' "No Occurrence" Judgments
 Plaintiffs moved for partial summary judgment on the issue of coverage under the 1983-84 policy with respect to the liabilities for the Pennsylvania and South Carolina third-party sites. In response, Republic cross-moved for summary judgment on the basis of several defenses, one of which being that plaintiffs either expected or intended the damage at the two third-party sites. The essential facts concerning each third-party site are as follows.
 1. The Erie, Pennsylvania, Waste Disposal Site
 From 1973 to 1981, Urick Foundry (Urick), a division of Emerson's Ridge Tool Company (Ridge Tool) located in Erie, Pennsylvania, hired a licensed local hauler, Sitter Trucking Company (Sitter), to dispose of Urick's foundry sand and other non-hazardous wastes at an off-site location to be selected by Sitter. Plaintiffs offered evidence that Urick expected and intended that Sitter would dispose of the wastes at a proper disposal facility and did not expect or intend the wastes to be discharged from a disposal facility or to cause damage to the environment.
 However, Sitter commingled Urick's foundry sand along with other companies' wastes and improperly disposed of the wastes at the Erie, Pennsylvania, site, an unlicensed landfill owned in part by Sitter. Plaintiffs offered evidence that Sitter's actions were unknown to Urick and contrary to its expectation and intention, that Sitter did not inform Urick that it was hauling Urick's foundry sand to the site, and that none of the shipping records indicate where Sitter was hauling the sand.
 The landfill in question, known as the Millcreek Landfill, was operated from 1941 until it was closed by the State of Pennsylvania in 1981, subsequent to the state's discovery that it was being illegally operated. In 1982, pursuant to its Superfund authority, the United States Environmental Protection Agency (the EPA) conducted an investigation of soil, sediment, groundwater and surface water contamination at the site. The tests confirmed soil and groundwater contamination.
 At or about the same time, a neighboring landowner, Ralph Riehl, filed a lawsuit against plaintiffs and other potentially responsible parties. In 1983, the Millcreek Landfill was proposed to the EPA's National Priorities List.*fn7 On September 16, 1983, Urick received a notice of potential liability (PRP letter) from the EPA. On September 30, 1983, the law firm of MacDonald, Illig, Jones & Britton responded to the EPA's PRP letter by acknowledging that the firm represented Urick in conjunction with the Millcreek site. On October 2, 1983, the law firm, acting on behalf of Urick and other potentially responsible parties, participated in a conference with the EPA regarding the investigation and cleanup at the Millcreek Landfill.
 In June of 1992, the EPA sued Urick pursuant to the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA) (42 U.S.C. §9601 et seq. (1988)), seeking recovery of costs expended to investigate and remediate the site. Subsequently, in 1993, the Pennsylvania Department of Environmental Resources (PADER) also sued Urick concerning the contamination at the site. Urick settled those suits in 1996.
 2. The South Carolina Waste Disposal Site
 The facts relating to the Dixiana, South Carolina, site are similar to those relating to the Erie, Pennsylvania, site. On approximately 10 occasions between April of 1978 and March of 1980, South Carolina Recycling and Disposal, Inc. (SCRDI), a licensed hauler, removed chemical wastes from Emerson's former manufacturing facility, Therm-O-Disc Incorporated (Therm-O-Disc), in Aiken, South Carolina. Plaintiffs offered evidence that Therm-O-Disc expected SCRDI to dispose of the wastes properly and did not expect or intend the wastes to be discharged from a disposal facility or to damage the environment.
 Plaintiffs offered evidence that, unbeknownst to Therm-O-Disc and contrary to its expectations and intentions, SCRDI stored and handled Therm-O-Disc's wastes improperly at the waste disposal site. Between 1978 and 1980, SCRDI stored more than 1,100 drums containing various types of wastes at the site; many of the drums deteriorated and leaked as a result of SCRDI's allegedly improper handling practices. The EPA confirmed groundwater contamination at the site between 1980 and 1982, leading to the site's placement on the National Priorities List in December of 1982. The EPA and state environmental officials investigated the site from 1984 to 1986 and ultimately concluded that contamination was migrating through the groundwater underneath the site.
 In December of 1988, the EPA sent Therm-O-Disc an information request concerning the site. By a letter dated February 14, 1989, the EPA demanded that Therm-O-Disc reimburse it for its costs associated with investigation and remediation of the site. The EPA alleged that Therm-O-Disc sent drums to the site and that releases from those drums caused or contributed to the contamination of the site. Subsequently, in April of 1992, pursuant to CERCLA, the EPA sued Therm-O-Disc and two other companies that allegedly shipped material to the site. In January of 1995, Therm-O-Disc settled with the EPA and agreed, as part of the settlement, to reimburse the government for past costs to a certain date and to take over operation and maintenance of the site's groundwater remediation system.
 Trial Court's Judgments with Respect to the Third-Party Waste Disposal Sites
 In opposition to plaintiffs' motions for summary judgment and in support of its own motions for summary judgment, Republic argued, in part, that plaintiffs failed to prove a covered "occurrence" because they were aware of the property damage at the two third-party sites prior to the inception of the 1983-84 policy. Plaintiffs responded to Republic's cross-motion with evidence that disputed the accuracy and relevance of Republic's evidence and the inferences which Republic drew from that evidence.
 On August 29, 2002, the trial court denied plaintiffs' motions for partial summary judgment and granted Republic's cross-motions. The trial court found that plaintiffs had failed to demonstrate a covered "occurrence" at either site because they "expected and intended," prior to the inception of the policy, the property damage that took place at the two sites.
 The Owned Sites' "Intentional Pollution" Judgments
 Republic moved for summary judgment on the issue of coverage for owned sites located in Alabama, Louisiana, Mississippi, and New York, based on the inapplicability of the "sudden and accidental" exception to the pollution exclusion contained in the 1984-85 policy. Republic similarly moved for summary judgment on the issue of coverage with respect to those four sites and cross-moved for summary judgment in conjunction with its opposition to plaintiffs' motion for partial summary judgment as to the Hatfield, Pennsylvania, site,*fn8 based on the inapplicability of the customized "accidental" exception to the pollution exclusion contained in the 1983-84 policy. Republic, in essence, argued that the discharges of pollutants were neither "sudden" nor "accidental," thereby precluding coverage. The essential facts concerning each owned site are as follows.
 1. The Alabama Owned Site
 Emerson's Wiegand Appliance Division (Wiegand) built the Vernon, Alabama, facility on undeveloped land in 1976. That facility began operations in 1976 and manufactured electrical resistance heating units.
 In 1981, Wiegand constructed a state-licensed concrete storage pad that was designed to hold virgin and waste materials, including oils, trichloroethylene (TCE) and trichloroethane (TCA). The storage pad, surrounded by a concrete curb, contained no passageways, such as pipes or drains, through which chemicals could have traveled to other parts of the site. A grated concrete containment trench was built around the storage pad. The trench was built specifically to contain discharges that otherwise might have been released from the storage pad.
 TCA was stored on the storage pad in 55-gallon drums, and TCE was stored in a 5,000-gallon aboveground storage tank. TCE was delivered to the aboveground storage tank via a truck and distributed throughout the plant by an underground pipe.
 Sometime in 1981 or 1982, Vernon's coordinator of environmental compliance observed stained soil around the storage pad. The soil was eventually removed and disposed of as hazardous waste. In the mid-1980s, the compliance coordinator also learned that some employees had, on an unspecified number of occasions, poured small amounts of spent TCA onto the ground near the storage pad, as was evidenced by dead grass.
 At some point, a sump was constructed in the concrete storage pad to collect rainwater and other materials that would spill onto the storage pad. There was no drain or outlet from the sump. Liquids collected in the sump were periodically pumped out and discharged into a sanitary sewer. Visible staining of the soils showed that the sump may have overflowed in the past. In the event of an overflow, the water from the storage area would flow across an adjacent unpaved area for approximately 40 feet to a paved road. The water would then flow along the curb of the road to the point where the road ended. From the end of the road, the water would flow some 100 yards to a neighboring small creek. Republic alleged that overflows were routine occurrences over the years whenever heavy rains fell, resulting in contaminated water flowing down the road and toward the creek.
 In 1988, Wiegand constructed a hazardous waste storage pad adjacent to the concrete storage pad. That hazardous waste storage pad, where spent TCE was stored, did not contain a sump or a trench.
 In July of 1989, outside the coverage period of the policies at issue, Emerson's corporate representative conducted an internal environmental compliance audit of the facility. It appears that in his report he stated that he observed a leak in one of the pump seals to the 5,000-gallon TCE above-ground storage tank, a rusted drum containing TCE and other material dripping onto the concrete storage pad, and staining of the concrete storage pad and surrounding soil.
 After the audit, in 1990, Emerson retained Radian Corporation (Radian) to conduct an investigation of Wiegand's operations. Radian determined that the staining around the concrete storage pad was due to leakage from the underground pipeline, leakage from an aboveground pipe connected to the pipeline, as well as storm water runoff from the pad. Radian also discovered on-site and off-site soil and groundwater contamination caused by total petroleum hydrocarbons and volatile organic compounds, including TCE and TCA. Although plaintiffs have admitted that the contamination at the Vernon facility was the result of slow leakage over a considerable period of time, plaintiffs claim that long-time Wiegand employees had also identified at least two abrupt, unexpected, and unintended releases of TCE during plant operations, which may have contributed to the contamination at the site. These releases allegedly occurred in 1975 and 1977 or 1978. Republic disputes this claim based on the fact that plaintiffs' corporate representative testified in a deposition that he could not recall any abrupt or accidental discharges having occurred at the Vernon site.
 2. The Louisiana Owned Site
 Emerson's Poulan/Weed Eater Division (Poulan/Weed Eater) manufactured chainsaws and consumer lawn trimmers at its Shreveport, Louisiana, facility from 1971 until 1983. In 1986, Emerson sold Poulan/Weed Eater to White Consolidated Industries (WCI). Subsequently, WCI, with the assistance of its environmental consultant, discovered soil and groundwater contamination caused by heavy metals and chlorinated solvents, including TCE and TCA, at the site.
 From 1971 to 1980, Poulan/Weed Eater operated a permitted wastewater treatment system that was designed to treat heavy metal and solvent wastes from the facility's manufacturing operations. Waste streams from Poulan/Weed Eater industrial processes contained cyanide, heavy metals and industrial solvents (TCA and TCE). These streams passed through a treatment facility and were separated to create a sludge that, depending on the time period, was directed to one of three industrial waste lagoons. The first lagoon was used from 1971 to 1975, the second lagoon was used from 1975 to 1979, and the third lagoon was used from 1979 to 1980. The lagoons were intended to hold the sludge permanently, while any water remaining in the sludge was intended to evaporate into the atmosphere or to percolate into the subsurface. The remaining treated water was discharged into a sanitary waste lagoon. Wastes from Poulan/Weed Eater's plating operations were sent to a series of underground tanks for treatment and then were pumped into one of the lagoons, where metal sludge would accumulate. On-site settling lagoons were discontinued in August of 1980 and a new continuous wastewater treatment system was installed.
 During the years the manufacturing facility was in operation, TCA and TCE were used in a degreasing unit and were kept in an aboveground storage tank located on a concrete pier or slab outside the plant building. That tank was taken out of service and removed in 1983. Acetone was used to clean the chainsaws and was stored in five-gallon cans in an oil storage shed in the back of the plant. Chromic acid was used in the plating operations, and cyanide was used in the heat-treating system. Spent TCA and TCE, as well as acetone and toluene (used during the installation of handlebars on the chainsaws), were stored in an underground storage tank. That tank was removed from the site in 1986. As noted above, used chromates and cyanide were pumped into treatment tanks, and then the sludge was pumped into one of the industrial lagoons.
 The principal contaminants discovered at the site were TCA and TCE. The primary source of TCE in the groundwater was identified to be the three industrial waste lagoons. Contamination was also discovered at the location of the aboveground TCA/TCE storage tank, the concrete pier, and the underground solvent waste tank.
 Plaintiffs claim that some contamination may have been accidental and point to two separate incidents in 1973 and 1974, when magnesium, used to build chainsaws, spontaneously combusted as a result of inadvertent contact with water. With respect to the 1973 incident, the combusting magnesium resulted in a large fire and explosion that destroyed a solvent storage area and caused the death of an employee. The 1974 incident occurred in the same general area of the facility as the 1973 incident.
 3. The Mississippi Owned Site
 In 1988, after an internal environmental audit, Emerson retained Radian to investigate the surface impoundment*fn9 constructed in 1974 by Emerson's U.S. Electrical Motors Division at its Philadelphia, Mississippi, facility. Processed rinsewater from various plant operations was piped to that surface impoundment, where the water would either evaporate or be discharged into the sewer system for the City of Philadelphia. Plaintiffs claim that the impoundment was constructed with a specially lined clay surface. However, the report prepared by Radian states that the impoundment is unlined. Rather, the impoundment sits on top of approximately nine feet of natural clay. Radian's investigation determined that there was soil and groundwater contamination, which was caused by the seepage of wastes through the natural clay bottom of the impoundment.
 4. The New York Owned Site
 Emerson's McPhilben Lighting Company (McPhilben) manufactured industrial lighting fixtures at its Melville, New York, facility from 1963 until 1989, when McPhilben was sold. In preparation for its sale of McPhilben and in compliance with New York law, Emerson hired Radian to perform an environmental audit of the site. Radian discovered that contaminants had escaped into the surrounding soils and groundwater from two underground holding tanks and six dry wells, also called leaching pools, which were intended to hold wastes from plant operations while allowing treated water to escape. Additionally, Radian discovered an area of the facility where xylene, a volatile organic compound, negatively impacted the soil. That contamination arose from a hole that was cut in the bottom of a trench near wastewater tanks. The hole was apparently cut intentionally in order to clean out the pipe running underneath the trench.
 5. The Pennsylvania Owned Site
 From 1964 to 1969, Emerson's Brooks Instruments Division (Brooks) manufactured precision instruments and calibration equipment at a facility located on Church Road near Hatfield, Pennsylvania. In 1987, the EPA named Brooks a potentially responsible party with respect to the site, which had a contaminated aquifer running beneath it. Brooks' use of TCE at its facility allegedly contributed to the contamination of the aquifer. Brooks' long-time employees had no recollection of any spills or releases of TCE taking place at the Church Road facility. There was evidence that ...